STAT3 inhibitor containing quinolinecarboxamide derivative as active ingredient

1. A method of inhibiting a STAT3 activity, comprising administering to a subject in need thereof a STAT3 inhibitor comprising a quinolinecarboxamide derivative represented by the formula (I), as an active ingredient:

wherein

R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 9 (wherein R 9 represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group), COOR 10 (wherein R 10 is as defined above in R 9 ), C(=Q 1 )NR 11 R 12 (wherein Q 1 represents an oxygen atom, a sulfur atom, or NR 13 (wherein R 13 is as defined above in R 9 ), and R 11 and R 12 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group, or a group which is formed by linking R 11 and R 12 together represents a nitrogen-containing heterocyclic group], OR 14 (wherein R 14 is as defined above in R 9 ), OCOR 15 (wherein R 15 is as defined above in R 9 ), S(O)mR 16 (wherein m represents 0, 1, or 2, and R 16 is as defined above in R 9 ), SO 2 NR 17 R 18 (wherein R 17 and R 18 are the same or different and are as defined above in R 11 and R 12 , respectively), NR 19 R 20 (wherein R 19 and R 20 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 21 (wherein R 21 is as defined above in R 9 ), COOR 22 (wherein R 22 is as defined above in R 9 ), or SO 2 R 23 (wherein R 23 is as defined above in R 9 ), or a group which is formed by linking R 19 and R 20 together represents a nitrogen-containing heterocyclic group), N(R 24 )C(=Q 2 )NR 25 R 26 (wherein Q 2 represents an oxygen atom, a sulfur atom, NR 27 (wherein R 27 is as defined above in R 9 ), NCN, CHNO 2 , or C(CN) 2 , R 24 is as defined above in R 9 , and R 25 and R 26 are the same or different and are as defined above in R 11 and R 12 , respectively), N(R 28 )SO 2 NR 29 R 30 (wherein R 28 is as defined above in R 9 , and R 29 and R 30 are the same or different and are as defined above in R 11 and R 12 , respectively), SiR 31 R 32 R 33 (wherein R 31 , R 32 , and R 33 are the same or different and are each as defined above in R 9 ), a nitro group, a cyano group, or a halogen atom, wherein any two adjacent groups of R 3 to R 8 may be linked together to form a substituted or unsubstituted alicyclic hydrocarbon ring, alicyclic heterocyclic ring, aromatic hydrocarbon ring, or aromatic heterocyclic ring;

W represents a single bond or a substituted or unsubstituted alkylene group; and

X represents an oxygen atom, a sulfur atom, or NR 34 (wherein R 34 is as defined above in R 9 ), wherein when X is a sulfur group, R 1 is not a substituted alkyl group, or a pharmacologically acceptable salt thereof.

2. The method according to claim 1 , wherein X is an oxygen atom, and the quinolinecarboxamide derivative is represented by the formula (Ia):

or a pharmacologically acceptable salt thereof.

3. The method according to claim 2 , wherein W in the quinolinecarboxamide derivative of the formula (Ia) is a single bond,

or a pharmacologically acceptable salt thereof.

4. The method according to claim 3 , wherein R 1 and R 3 in the quinolinecarboxamide derivative of the formula (Ia) are the same or different and each are a substituted or unsubstituted aryl group, a substituted or unsubstituted aromatic heterocyclic group, a styryl group, or an alkoxy group,

or a pharmacologically acceptable salt thereof.

5. The method according to claim 4 , wherein the aryl group is present in the quinolinecarboxamide derivative of the formula (Ia) and is a phenyl group or a naphthyl group,

or a pharmacologically acceptable salt thereof.

6. The method according to claim 4 , wherein the aromatic heterocyclic group is present in the quinolinecarboxamide derivative of the formula (Ia) and is a furyl group or a thienyl group,

or a pharmacologically acceptable salt thereof.

7. The method according to claim 4 , wherein R 1 in the quinolinecarboxamide derivative of the formula (Ia) is a furyl group, and R 3 is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted furyl group, a substituted or unsubstituted thienyl group, or a styryl group,

or a pharmacologically acceptable salt thereof.

8. The method according to claim 7 , wherein R 6 in the quinolinecarboxamide derivative of the formula (Ia) is a fluorine atom, a chlorine atom, a bromine atom, a methyl group, a phenyl group, a hydroxyphenyl group, a thienyl group, a pyridyl group, a methoxy group, or a trifluoromethoxy group,

or a pharmacologically acceptable salt thereof.

9. The method according to claim 4 or 5 , wherein R 1 in the quinolinecarboxamide derivative of the formula (Ia) is a substituted or unsubstituted phenyl group, and R 3 is a phenyl group,

or a pharmacologically acceptable salt thereof.

10. The method according to claim 9 , wherein R 6 in the quinolinecarboxamide derivative of the formula (Ia) is a chlorine atom or a trifluoromethoxy group,

or a pharmacologically acceptable salt thereof.

11. The method according to claim 2 , wherein R 2 in the quinolinecarboxamide derivative of the formula (Ia) is a hydrogen atom,

or a pharmacologically acceptable salt thereof.

12. The method according to claim 1 , wherein X is a sulfur atom, and the quinolinecarboxamide derivative is represented by the formula (Ib):

or a pharmacologically acceptable salt thereof.

13. The method according to claim 12 , wherein W in the quinolinecarboxamide derivative of the formula (Ib) is a single bond,

or a pharmacologically acceptable salt thereof.

14. The method according to claim 13 , wherein R 1 and R 3 in the quinolinecarboxamide derivative of the formula (Ib) are the same or different and each are a substituted or unsubstituted aryl group or a substituted or unsubstituted aromatic heterocyclic group,

or a pharmacologically acceptable salt thereof.

15. The method according to claim 14 , wherein R 1 in the quinolinecarboxamide derivative of the formula (Ib) is a pyridyl group, and R 3 is a substituted or unsubstituted phenyl group, a substituted or unsubstituted furyl group, a substituted or unsubstituted thienyl group, or a pyridyl group,

or a pharmacologically acceptable salt thereof.

16. The method according to claim 15 , wherein R 2 in the quinolinecarboxamide derivative of the formula (Ib) is a hydrogen atom,

or a pharmacologically acceptable salt thereof.

17. A method for treating cancer comprising administering to a subject in need thereof an anticancer agent comprising a STAT3 inhibitor, wherein the STAT3 inhibitor comprises a quinolinecarboxamide derivative represented by the formula (I) or a pharmacologically acceptable salt thereof, as an active ingredient:

wherein

R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 9 (wherein R 9 represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group), COOR 10 (wherein R 10 is as defined above in R 9 ), C(=Q 1 )NR 11 R 12 (wherein Q 1 represents an oxygen atom, a sulfur atom, or NR 13 (wherein R 13 is as defined above in R 9 ), and R 11 and R 12 are the same or different and each represent a hydrogen atom a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group, or a group which is formed by linking R 11 and R 12 together represents a nitrogen-containing heterocyclic group], OR 14 (wherein R 14 is as defined above in R 9 ), OCOR 15 (wherein R 15 is as defined above in R 9 ), S(O)mR 16 (wherein m represents 0, 1, or 2, and R 16 is as defined above in R 9 ), SO 2 NR 17 R 18 (wherein R 17 and R 18 are the same or different and are as defined above in R 11 and R 12 , respectively), NR 19 R 20 (wherein R 19 and R 20 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 21 (wherein R 21 is as defined above in R 9 ), COOR 22 (wherein R 22 is as defined above in R 9 ), or SO 2 R 23 (wherein R 23 is as defined above in R 9 ), or a group which is formed by linking R 19 and R 20 together represents a nitrogen-containing heterocyclic group), N(R 24 )C(=Q 2 )NR 25 R 26 (wherein Q 2 represents an oxygen atom, a sulfur atom, NR 27 (wherein R 27 is as defined above in R 9 ), NCN, CHNO 2 , or C(CN) 2 , R 24 is as defined above in R 9 , and R 25 and R 26 are the same or different and are as defined above in R 11 and R 12 , respectively), N(R 28 ) SO 2 NR 29 R 30 (wherein R 28 is as defined above in R 9 , and R 29 and R 30 are the same or different and are as defined above in R 11 and R 12 , respectively), SiR 31 R 32 R 33 (wherein R 31 , R 32 , and R 33 are the same or different and are each as defined above in R 9 ), a nitro group, a cyano group, or a halogen atom, wherein any two adjacent groups of R 3 to R 8 may be linked together to form a substituted or unsubstituted alicyclic hydrocarbon ring, alicyclic heterocyclic ring, aromatic hydrocarbon ring, or aromatic heterocyclic ring;

W represents a single bond or a substituted or unsubstituted alkylene group; and

X represents an oxygen atom, a sulfur atom, or NR 34 (wherein R 34 is as defined in R 9 ),

wherein when X is a sulfur group, R 1 is not a substituted alkyl group.

18. A quinolinecarboxamide derivative, represented by the formula (I-1):

wherein

R 1 , R 2 , R 3 , R 5a , R 6a , R 7a and R 8a are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 9 (wherein R 9 represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group), COOR 10 (wherein R 10 is as defined above in R 9 ), C(=Q 1 )NR 11 R 12 (wherein Q 1 represents an oxygen atom, a sulfur atom, or NR 13 (wherein R 13 is as defined above in R 9 ), and R 11 and R 12 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group, or a group which is formed by linking R 11 and R 12 together represents a nitrogen-containing heterocyclic group), OR 14 (wherein R 14 is as defined above in R 9 ), OCOR 15 (wherein R 15 is as defined above in R 9 ), S(O)mR 16 (wherein m represents 0, 1, or 2, and R 16 is as defined above in R 9 ), SO 2 NR 17 R 18 (wherein R 17 and R 18 are the same or different and are as defined above in R 11 and R 12 , respectively), NR 19 R 20 (wherein R 19 and R 20 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 21 (wherein R 21 is as defined above in R 9 ), COOR 22 (wherein R 22 is as defined above in R 9 ), or SO 2 R 23 (wherein R 23 is as defined above in R 9 ), or a group which is formed by linking R 19 and R 20 together represents a nitrogen-containing heterocyclic group), N(R 24 )C(=Q 2 )NR 25 R 26 (wherein Q 2 represents an oxygen atom, a sulfur atom, NR 27 (wherein R 27 is as defined above in R 9 ), NCN, CHNO 2 , or C(CN) 2 , R 24 is as defined above in R 9 , and R 25 and R 26 are the same or different and are as defined above in R 11 and R 12 , respectively), N(R 28 )SO 2 NR 29 R 30 (wherein R 28 is as defined above in R 9 , and R 29 and R 30 are the same or different and are as defined above in R 11 and R 12 , respectively), SiR 31 R 32 R 33 (wherein R 31 , R 32 , and R 33 are the same or different and are each as defined above in R 9 ), a nitro group, a cyano group, or a halogen atom, and any two adjacent groups of R 3 to R 8 may be linked together to form a substituted or unsubstituted alicyclic hydrocarbon ring, alicyclic heterocyclic ring, aromatic hydrocarbon ring, or aromatic heterocyclic ring,

R 4a is a hydrogen atom, an unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 9 (wherein R 9 represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group), COOR 10 (wherein R 10 is as defined above in R 9 ), C(=Q 1 )NR 11 R 12 (wherein Q 1 represents an oxygen atom, a sulfur atom, or NR 13 (wherein R 13 is as defined above in R 9 ), and R 11 and R 12 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group, or a group which is formed by linking R 11 and R 12 together represents a nitrogen-containing heterocyclic group), OR 14 (wherein R 14 is as defined above in R 9 ), OCOR 15 (wherein R 15 is as defined above in R 9 ), S(O)mR 16 (wherein in represents 0, 1, or 2, and R 16 is as defined above in R 9 ), SO 2 NR 17 R 18 (wherein R 17 and R 18 are the same or different and are as defined above in R 11 and R 12 , respectively), NR 19 R 20 (wherein R 19 and R 20 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 21 (wherein R 21 is as defined above in R 9 ), COOR 22 (wherein R 22 is as defined above in R 9 ), or SO 2 R 23 (wherein R 23 is as defined above in R 9 ), or a group which is formed by linking R 19 and R 20 together represents a nitrogen-containing heterocyclic group), N(R 24 )C(=Q 2 )NR 25 R 26 (wherein Q 2 represents an oxygen atom, a sulfur atom, NR 27 (wherein R 27 is as defined above in R 9 ), NCN, CHNO 2 , or C(CN) 2 , R 24 is as defined above in R 9 , and R 25 and R 26 are the same or different and are as defined above in R 11 and R 12 , respectively), N(R 28 )SO 2 NR 29 R 30 (wherein R 28 is as defined above in R 9 , and R 29 and R 30 are the same or different and are as defined above in R 11 and R 12 , respectively), SiR 31 R 32 R 33 (wherein R 31 , R 32 , and R 33 are the same or different and are each as defined above in R 9 ), a nitro group, a cyano group, or a halogen atom, and any two adjacent s of R 3 to R 8 may be linked together to form a substituted or unsubstituted alicyclic hydrocarbon ring, alicyclic heterocyclic ring, aromatic hydrocarbon ring, or aromatic heterocyclic ring,

wherein at least one group of R 4a , R 5a , R 6a , R 7a , and R 8a represents a group other than a hydrogen atom;

W represents a single bond or a substituted or unsubstituted alkylene group; and

X represents an oxygen atom, a sulfur atom, or NR 34 (wherein R 34 is as defined above in R 9 ),

or a pharmacologically acceptable salt thereof.

19. The quinolinecarboxamide derivative according to claim 18 , represented by the formula (I-1a):

wherein R 1a and R 3a are the same or different and each represent a substituted or unsubstituted aryl group or a substituted or unsubstituted aromatic heterocyclic group,

or a pharmacologically acceptable salt thereof.

20. The quinolinecarboxamide derivative according to claim 19 , wherein in R 1a and R 3a , the aryl group is present and is a phenyl group, and/or the aromatic heterocyclic group is present and is a furyl group or a thienyl group,

or a pharmacologically acceptable salt thereof.

21. The quinolinecarboxamide derivative according to claim 19 or 20 , wherein R 1a is a furyl group, and R 3a is a substituted or unsubstituted phenyl group, a furyl group, or a thienyl group,

or a pharmacologically acceptable salt thereof.

22. The quinolinecarboxamide derivative according to claim 19 , wherein at least one group of R 4a , R 5a , R 6a , R 7a , and R 8a is a fluorine atom, a chlorine atom, a bromine atom, a methyl group, a phenyl group, a hydroxyphenyl group, a thienyl group, a pyridyl group, a methoxy group, or a trifluoromethoxy group,

or a pharmacologically acceptable salt thereof.

23. The quinolinecarboxamide derivative according to claim 19 or 20 , wherein R 1a is a substituted or unsubstituted phenyl group, and R 3a is a phenyl group,

or a pharmacologically acceptable salt thereof.

24. The quinolinecarboxamide derivative according to claim 19 , wherein R 6a is a chlorine atom or a trifluoromethoxy group,

or a pharmacologically acceptable salt thereof.

25. A quinolinecarboxamide derivative represented by the formula (I-2):

wherein R 3b represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group other than a phenyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group other than 2-thienyl, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 9 (wherein R 9 represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group), COOR 10 (wherein R 10 is as defined above in R 9 ), C(=Q)NR 11 R 12 (wherein Q 1 represents an oxygen atom, a sulfur atom, or NR 13 (wherein R 13 is as defined above in R 9 ), and R 11 and R 12 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group, or a group which is formed by linking R 11 and R 12 together represents a nitrogen-containing heterocyclic group), OR 14 (wherein R 14 is as defined above in R 9 ), OCOR 15 (wherein R 15 is as defined above in R 9 ), S(O)mR 16 (wherein m represents 0, 1, or 2, and R 16 is as defined above in R 9 ), SO 2 NR 17 R 18 (wherein R 17 and R 18 are the same or different and are as defined above in R 11 and R 12 , respectively), NR 19 R 20 (wherein R 19 and R 20 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 21 (wherein R 21 is as defined above in R 9 ), COOR 22 (wherein R 22 is as defined above in R 9 ), or SO 2 R 23 (wherein R 23 is as defined above in R 9 ), or a group which is formed by linking R 19 and R 20 together represents a nitrogen-containing heterocyclic group), N(R 24 )C(=Q 2 )NR 25 R 26 (wherein Q 2 represents an oxygen atom, a sulfur atom, NR 27 (wherein R 27 is as defined above in R 9 ), NCN, CHNO 2 , or C(CN) 2 , R 24 is as defined above in R 9 , and R 25 and R 26 are the same or different and are as defined above in R 1l and R 12 , respectively), N(R 28 )SO 2 NR 29 R 30 (wherein R 28 is as defined above in R 9 , and R 29 and R 30 are the same or different and are as defined above in R 11 and R 12 , respectively), SiR 31 R 32 R 33 (wherein R 31 , R 32 , and R 33 are the same or different and are each as defined above in R 9 ), a nitro group, a cyano group, or a halogen atom;

R 2 is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 9 (wherein R 9 represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group), COOR 10 (wherein R 10 is as defined above in R 9 ), C(=Q 1 )NR 11 R 12 (wherein Q 1 represents an oxygen atom, a sulfur atom, or NR 13 (wherein R 13 is as defined above in R 9 ), and R 11 and R 12 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group, or a group which is formed by linking R 11 and R 12 together represents a nitrogen-containing heterocyclic group], OR 14 (wherein R 14 is as defined above in R 9 ), OCOR 15 (wherein R 15 is as defined above in R 9 ), S(O)mR 16 (wherein m represents 0, 1, or 2, and R 16 is as defined above in R 9 ), SO 2 NR 17 R 18 (wherein R 17 and R 18 are the same or different and are as defined above in R 11 and R 12 , respectively), NR 19 R 20 (wherein R 19 and R 20 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 21 (wherein R 21 is as defined above in R 9 ), COOR 22 (wherein R 22 is as defined above in R 9 ), or SO 2 R 23 (wherein R 23 is as defined above in R 9 ), or a group which is formed by linking R 19 and R 20 together represents a nitrogen-containing heterocyclic group), N(R 24 )C(=Q 2 )NR 25 R 26 (wherein Q 2 represents an oxygen atom, a sulfur atom, NR 27 (wherein R 27 is as defined above in R 9 ), NCN, CHNO 2 , or C(CN) 2 , R 24 is as defined above in R 9 , and R 25 and R 26 are the same or different and are as defined above in R 11 and R 12 , respectively), N(R 28 )SO 2 NR 29 R 30 (wherein R 28 is as defined above in R 9 , and R 29 and R 30 are the same or different and are as defined above in R 11 and R 12 , respectively), SiR 31 R 32 R 33 (wherein R 31 , R 32 , and R 33 are the same or different and are each as defined above in R 9 ), a nitro group, a cyano group, or a halogen atom, wherein any two adjacent groups of R 3 to R 8 may be linked together to form a substituted or unsubstituted alicyclic hydrocarbon ring, alicyclic heterocyclic ring, aromatic hydrocarbon ring, or aromatic heterocyclic ring;

W represents a single bond or a substituted or unsubstituted alkylene group; and

X represents an oxygen atom, a sulfur atom, or NR 34 (wherein R 34 is as defined above in R 9 ),

or a pharmacologically acceptable salt thereof.

26. The quinolinecarboxamide derivative according to claim 25 , represented by the formula (I-2a):

wherein R 3c represents a substituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted furyl group, a substituted thienyl group, a styryl group, or an alkoxy group,

or a pharmacologically acceptable salt thereof.

27. A method of inhibiting a STAT3 activity, comprising administering to a subject in need thereof a STAT3 inhibitor comprising a quinolinecarboxamide derivative represented by the formula (I-1), as an active ingredient:

wherein

R 1 , R 2 , R 3 , R 5a , R 6a , R 7a , and R 8a are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 9 (wherein R 9 represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group), COOR 10 (wherein R 10 is as defined above in R 9 ), C(=Q 1 )NR 11 R 12 (wherein Q 1 represents an oxygen atom, a sulfur atom, or NR 13 (wherein R 13 is as defined above in R 9 ), and R 11 and R 12 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group, or a group which is formed by linking R 11 and R 12 together represents a nitrogen-containing heterocyclic group), OR 14 (wherein R 14 is as defined above in R 9 ), OCOR 15 (wherein R 15 is as defined above in R 9 ), S(O)mR 16 (wherein m represents 0, 1, or 2, and R 16 is as defined above in R 9 ), SO 2 NR 17 R 18 (wherein R 17 and R 18 are the same or different and are as defined above in R 11 and R 12 , respectively), NR 19 R 20 (wherein R 19 and R 20 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 21 (wherein R 21 is as defined above in R 9 ), COOR 22 (wherein R 22 is as defined above in R 9 ), or SO 2 R 23 (wherein R 23 is as defined above in R 9 ), or a group which is formed by linking R 19 and R 20 together represents a nitrogen-containing heterocyclic group), N(R 24 )C(=Q 2 )NR 25 R 26 (wherein Q 2 represents an oxygen atom, a sulfur atom, NR 27 (wherein R 27 is as defined above in R 9 ), NCN, CHNO 2 , or C(CN) 2 , R 24 is as defined above in R 9 , and R 25 and R 26 are the same or different and are as defined above in R 11 and R 12 , respectively), N(R 28 )SO 2 NR 29 R 30 (wherein R 28 is as defined above in R 9 , and R 29 and R 30 are the same or different and are as defined above in R 11 and R 12 , respectively), SiR 31 R 32 R 33 (wherein R 31 , R 32 , and R 33 are the same or different and are each as defined above in R 9 ), a nitro group, a cyano group, or a halogen atom, and any two adjacent groups of R 3 to R 8 may be linked together to form a substituted or unsubstituted alicyclic hydrocarbon ring, alicyclic heterocyclic ring, aromatic hydrocarbon ring, or aromatic heterocyclic ring,

R 4a is a hydrogen atom, an unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 9 (wherein R 9 represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group), COOR 10 (wherein R 10 is as defined above in R 9 ), C(=Q 1 )NR 11 R 12 (wherein Q 1 represents an oxygen atom, a sulfur atom, or NR 13 (wherein R 13 is as defined above in R 9 ), and R 11 and R 12 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group, or a group which is formed by linking R 11 and R 12 together represents a nitrogen-containing heterocyclic group), OR 14 (wherein R 14 is as defined above in R 9 ), OCOR 15 (wherein R 15 is as defined above in R 9 ), S(O)mR 16 (wherein m represents 0, 1, or 2, and R 16 is as defined above in R 9 ), SO 2 NR 17 R 18 (wherein R 17 and R 18 are the same or different and are as defined above in R 11 and R 12 , respectively), NR 19 R 20 (wherein R 19 and R 20 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 21 (wherein R 21 is as defined above in R 9 ), COOR 22 (wherein R 22 is as defined above in R 9 ), or SO 2 R 23 (wherein R 23 is as defined above in R 9 ), or a group which is formed by linking R 19 and R 20 together represents a nitrogen-containing heterocyclic group), N(R 24 )C(=Q 2 )NR 25 R 26 (wherein Q 2 represents an oxygen atom, a sulfur atom, NR 27 (wherein R 27 is as defined above in R 9 ), NCN, CHNO 2 , or C(CN) 2 , R 24 is as defined above in R 9 , and R 25 and R 26 are the same or different and are as defined above in R 11 and R 12 , respectively), N(R 28 )SO 2 NR 29 R 30 (wherein R 28 is as defined above in R 9 , and R 29 and R 30 are the same or different and are as defined above in R 11 and R 12 , respectively), SiR 31 R 32 R 33 (wherein R 31 , R 32 , and R 33 are the same or different and are each as defined above in R 9 ), a nitro group, a cyano group, or a halogen atom, and any two adjacent groups of R 3 to R 8 may be linked together to form a substituted or unsubstituted alicyclic hydrocarbon ring, alicyclic heterocyclic ring, aromatic hydrocarbon ring, or aromatic heterocyclic ring,

wherein at least one group of R 4a , R 5a , R 6a , R 7a , and R 8a represents a group other than a hydrogen atom;

W represents a single bond or a substituted or unsubstituted alkylene group; and

X represents an oxygen atom, a sulfur atom, or NR 34 (wherein R 34 is as defined above in R 9 ),

or a pharmacologically acceptable salt thereof.

28. A method of inhibiting a STAT3 activity, comprising administering to a subject in need thereof a STAT3 inhibitor comprising a quinolinecarboxamide derivative represented by the formula (I-2), as an active ingredient:

wherein R 3b represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group other than a phenyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group other than 2-thienyl, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 9 (wherein R 9 represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group), COOR 10 (wherein R 10 is as defined above in R 9 ), C(=Q 1 )NR 11 R 12 (wherein Q 1 represents an oxygen atom, a sulfur atom, or NR 13 (wherein R 13 is as defined above in R 9 ), and R 11 and R 12 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group, or a group which is formed by linking R 11 and R 12 together represents a nitrogen-containing heterocyclic group), OR 14 (wherein R 14 is as defined above in R 9 ), OCOR 15 (wherein R 15 is as defined above in R 9 ), S(O)mR 16 (wherein m represents 0, 1, or 2, and R 16 is as defined above in R 9 ), SO 2 NR 17 R 18 (wherein R 17 and R 18 are the same or different and are as defined above in R 11 and R 12 , respectively), NR 19 R 20 (wherein R 19 and R 20 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 21 (wherein R 21 is as defined above in R 9 ), COOR 22 (wherein R 22 is as defined above in R 9 ), or SO 2 R 23 (wherein R 23 is as defined above in R 9 ), or a group which is formed by linking R 19 and R 20 together represents a nitrogen-containing heterocyclic group), N(R 24 )C(=Q 2 )NR 25 R 26 (wherein Q 2 represents an oxygen atom, a sulfur atom, NR 27 (wherein R 27 is as defined above in R 9 ), NCN, CHNO 2 , or C(CN) 2 , R 24 is as defined above in R 9 , and R 25 and R 26 are the same or different and are as defined above in R 11 and R 12 , respectively), N(R 28 )SO 2 NR 29 R 30 (wherein R 28 is as defined above in R 9 , and R 29 and R 30 are the same or different and are as defined above in R 11 and R 12 , respectively), SiR 31 R 32 R 33 (wherein R 31 , R 32 and R 33 are the same or different and are each as defined above in R 9 ), a nitro group, a cyano group, or a halogen atom;

R 2 is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 9 (wherein R 9 represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group), COOR 10 (wherein R 10 is as defined above in R 9 ), C(=Q 1 )NR 11 R 12 (wherein Q 1 represents an oxygen atom, a sulfur atom, or NR 13 (wherein R 13 is as defined above in R 9 ), and R 11 and R 12 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group, or a group which is formed by linking R 11 and R 12 together represents a nitrogen-containing heterocyclic group], OR 14 (wherein R 14 is as defined above in R 9 ), OCOR 15 (wherein R 15 is as defined above in R 9 ), S(O)mR 16 (wherein m represents 0, 1, or 2, and R 16 is as defined above in R 9 ), SO 2 NR 17 R 18 (wherein R 17 and R 18 are the same or different and are as defined above in R 11 and R 12 , respectively), NR 19 R 20 (wherein R 19 and R 20 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 21 (wherein R 21 is as defined above in R 9 ), COOR 22 (wherein R 22 is as defined above in R 9 ), or SO 2 R 23 (wherein R 23 is as defined above in R 9 ), or a group which is formed by linking R 19 and R 20 together represents a nitrogen-containing heterocyclic group), N(R 24 )C(=Q 2 )NR 25 R 26 (wherein Q 2 represents an oxygen atom, a sulfur atom, NR 27 (wherein R 27 is as defined above in R 9 ), NCN, CHNO 2 , or C(CN) 2 , R 24 is as defined above in R 9 , and R 25 and R 26 are the same or different and are as defined above in R 11 and R 12 , respectively), N(R 28 )SO 2 NR 29 R 30 (wherein R 28 is as defined above in R 9 , and R 29 and R 30 are the same or different and are as defined above in R 11 and R 12 , respectively), SiR 31 R 32 R 33 (wherein R 31 , R 32 , and R 33 are the same or different and are each as defined above in R 9 ), a nitro group, a cyano group, or a halogen atom, wherein any two adjacent groups of R 3 to R 8 may be linked together to form a substituted or unsubstituted alicyclic hydrocarbon ring, alicyclic heterocyclic ring, aromatic hydrocarbon ring, or aromatic heterocyclic ring;

W represents a single bond or a substituted or unsubstituted alkylene group; and

X represents an oxygen atom, a sulfur atom, or NR 34 (wherein R 34 is as defined above in R 9 ),

or a pharmacologically acceptable salt thereof.

29. A method for treating cancer, comprising administering to a subject in need thereof a STAT3 inhibitor comprising a quinolinecarboxamide derivative represented by the formula (I-1), as an active ingredient:

wherein

R 1 , R 2 , R 3 , R 5a , R 6a , R 7a , and R 8a are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 9 (wherein R 9 represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group), COOR 10 (wherein R 10 is as defined above in R 9 ), C(=Q 1 )NR 11 R 12 (wherein Q 1 represents an oxygen atom, a sulfur atom, or NR 13 (wherein R 13 is as defined above in R 9 ), and R 11 and R 12 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group, or a group which is formed by linking R 11 and R 12 together represents a nitrogen-containing heterocyclic group), OR 14 (wherein R 14 is as defined above in R 9 ), OCOR 15 (wherein R 15 is as defined above in R 9 ), S(O)mR 16 (wherein m represents 0, 1, or 2, and R 16 is as defined above in R 9 ), SO 2 NR 17 R 18 (wherein R 17 and R 18 are the same or different and are as defined above in R 11 and R 12 , respectively), NR 19 R 20 (wherein R 19 and R 20 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 21 (wherein R 21 is as defined above in R 9 ), COOR 22 (wherein R 22 is as defined above in R 9 ), or SO 2 R 23 (wherein R 23 is as defined above in R 9 ), or a group which is formed by linking R 19 and R 20 together represents a nitrogen-containing heterocyclic group), N(R 24 )C(=Q 2 )NR 25 R 26 (wherein Q 2 represents an oxygen atom, a sulfur atom, NR 27 (wherein R 27 is as defined above in R 9 ), NCN, CHNO 2 , or C(CN) 2 , R 24 is as defined above in R 9 , and R 25 and R 26 are the same or different and are as defined above in R 11 and R 12 , respectively), N(R 28 )SO 2 NR 29 R 30 (wherein R 28 is as defined above in R 9 , and R 29 and R 30 are the same or different and are as defined above in R 11 and R 12 , respectively), SiR 31 R 32 R 33 (wherein R 31 , R 32 , and R 33 are the same or different and are each as defined above in R 9 ), a nitro group, a cyano group, or a halogen atom, and any two adjacent groups of R 3 to R 8 may be linked together to form a substituted or unsubstituted alicyclic hydrocarbon ring, alicyclic heterocyclic ring, aromatic hydrocarbon ring, or aromatic heterocyclic ring,

R 4a is a hydrogen atom, an unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 9 (wherein R 9 represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group), COOR 10 (wherein R 10 is as defined above in R 9 ), C(=Q 1 )NR 11 R 12 (wherein Q 1 represents an oxygen atom, a sulfur atom, or NR 13 (wherein R 13 is as defined above in R 9 ), and R 11 and R 12 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group, or a group which is formed by linking R 11 and R 12 together represents a nitrogen-containing heterocyclic group), OR 14 (wherein R 14 is as defined above in R 9 ), OCOR 15 (wherein R 15 is as defined above in R 9 ), S(O)mR 16 (wherein m represents 0, 1, or 2, and R 16 is as defined above in R 9 ), SO 2 NR 17 R 18 (wherein R 17 and R 18 are the same or different and are as defined above in R 11 and R 12 , respectively), NR 19 R 20 (wherein R 19 and R 20 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 21 (wherein R 21 is as defined above in R 9 ), COOR 22 (wherein R 22 is as defined above in R 19 ), or SO 2 R 23 (wherein R 23 is as defined above in R 9 ), or a group which is formed by linking R 19 and R 20 together represents a nitrogen-containing heterocyclic group), N(R 24 )C(=Q 2 )NR 25 R 26 (wherein Q 2 represents an oxygen atom, a sulfur atom, NR 27 (wherein R 27 is as defined above in R 9 ), NCN, CHNO 2 , or C(CN) 2 , R 24 is as defined above in R 9 , and R 25 and R 26 are the same or different and are as defined above in R 11 and R 12 , respectively), N(R 28 )SO 2 NR 29 R 30 (wherein R 28 is as defined above in R 9 , and R 29 and R 30 are the same or different and are as defined above in R 11 and R 12 , respectively), SiR 31 R 32 R 33 (wherein R 31 , R 32 , and R 33 are the same or different and are each as defined above in R 9 ), a nitro group, a cyano group, or a halogen atom, and any two adjacent groups of R 3 to R 8 may be linked together to form a substituted or unsubstituted alicyclic hydrocarbon ring, alicyclic heterocyclic ring, aromatic hydrocarbon ring, or aromatic heterocyclic ring,

wherein at least one group of R 4a , R 5a , R 6a , R 7a , and R 8a represents a group other than a hydrogen atom;

W represents a single bond or a substituted or unsubstituted alkylene group; and

X represents an oxygen atom, a sulfur atom, or NR 34 (wherein R 34 is as defined above in R 9 ),

or a pharmacologically acceptable salt thereof.

30. A method for treating cancer, comprising administering to a subject in need thereof a STAT3 inhibitor comprising a quinolinecarboxamide derivative represented by the formula (I-2), as an active ingredient:

wherein R 3b represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group other than a phenyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group other than 2-thienyl, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 9 (wherein R 9 represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstrtuted aromatic heterocyclic alkyl group), COOR 10 (wherein R 10 is as defined above in R 9 ), C(=Q 1 )NR 11 R 12 (wherein Q 1 represents an oxygen atom, a sulfur atom, or NR 13 (wherein R 13 is as defined above in R 9 ), and R 11 and R 12 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group, or a group which is formed by linking R 11 and R 12 together represents a nitrogen-containing heterocyclic group), OR 14 (wherein R 14 is as defined above in R 9 ), OCOR 15 (wherein R 15 is as defined above in R 9 ), S(O)mR 16 (wherein m represents 0, 1, or 2, and R 16 is as defined above in R 9 ), SO 2 NR 17 , R 18 (wherein R 17 and R 18 are the same or different and are as defined above in R 11 and R 12 , respectively), NR 19 R 20 (wherein R 19 and R 20 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 21 (wherein R 21 is as defined above in R 9 ), COOR 22 (wherein R 22 is as defined above in R 9 ), or SO 2 R 23 (wherein R 23 is as defined above in R 9 ), or a group which is formed by linking R 19 and R 20 together represents a nitrogen-containing heterocyclic group), N(R 24 )C(=Q 2 )NR 25 R 26 (wherein Q 2 represents an oxygen atom, a sulfur atom, NR 27 (wherein R 27 is as defined above in R 9 ), NCN, CHNO 2 , or C(CN) 2 , R 24 is as defined above in R 9 , and R 25 and R 26 are the same or different and are as defined above in R 11 and R 12 , respectively), N(R 28 )SO 2 NR 29 R 30 (wherein R 28 is as defined above in R 9 , and R 29 and R 30 are the same or different and are as defined above in R 11 and R 12 , respectively), SiR 31 R 32 R 33 (wherein R 31 , R 32 , and R 33 are the same or different and are each as defined above in R 9 ), a nitro group, a cyano group, or a halogen atom;

R 2 is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 9 (wherein R 9 represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group), COOR 10 (wherein R 10 is as defined above in R 9 ), C(=Q 1 )NR 11 R 12 (wherein Q 1 represents an oxygen atom, a sulfur atom, or NR 13 (wherein R 13 is as defined above in R 9 ), and R 11 and R 12 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aromatic heterocyclic alkyl group, or a group which is formed by linking R 11 and R 12 together represents a nitrogen-containing heterocyclic group], OR 14 (wherein R 14 is as defined above in R 9 ), OCOR 15 (wherein R 15 is as defined above in R 9 ), S(O)mR 16 (wherein m represents 0, 1, or 2, and R 16 is as defined above in R 9 ), SO 2 NR 17 R 18 (wherein R 17 and R 18 are the same or different and are as defined above in R 11 and R 12 , respectively), NR 19 R 20 (wherein R 19 and R 20 are the same or different and each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic alkyl group, COR 21 (wherein R 21 is as defined above in R 9 ), COOR 22 (wherein R 22 is as defined above in R 9 ), or SO 2 R 23 (wherein R 23 is as defined above in R 9 ), or a group which is formed by linking R 19 and R 20 together represents a nitrogen-containing heterocyclic group), N(R 24 )C(=Q 2 )NR 25 R 26 (wherein Q 2 represents an oxygen atom, a sulfur atom, NR 27 (wherein R 27 is as defined above in R 9 ), NCN, CHNO 2 , or C(CN) 2 , R 24 is as defined above in R 9 , and R 25 and R 26 are the same or different and are as defined above in R 11 and R 12 , respectively), N(R 28 )SO 2 NR 29 R 30 (wherein R 28 is as defined above in R 9 , and R 29 and R 30 are the same or different and are as defined above in R 11 and R 12 , respectively), SiR 31 R 32 R 33 (wherein R 31 , R 32 , and R 33 are the same or different and are each as defined above in R 9 ), a nitro group, a cyano group, or a halogen atom, wherein any two adjacent groups of R 3 to R 8 may be linked together to form a substituted or unsubstituted alicyclic hydrocarbon ring, alicyclic heterocyclic ring, aromatic hydrocarbon ring, or aromatic heterocyclic ring;

W represents a single bond or a substituted or unsubstituted alkylene group; and

X represents an oxygen atom, a sulfur atom, or NR 34 (wherein R 34 is as defined above in R 9 ),

or a pharmacologically acceptable salt thereof.