Peptides comprising an epitope of the wilms tumor gene product

1. A compound of formula (1):

wherein X is a tyrosine residue or a methionine residue; each of Y and Z is independently selected from the group consisting of a single bond and a divalent peptide group consisting of 1-10 amino acid residues,

R 1 is hydrogen or alkyl,

R 2 is hydroxyl, amino, alkylamino or dialkylamino,

R 3 is hydrogen, alkyl, amino, alkylamino, dialkylamino or substituted or unsubstituted alkylcarbonylamino,

R 4 is hydrogen, alkyl, carboxy, carbamoyl, alkylcarbamoyl, dialkylcarbamoyl or a group of formula (2):

wherein W is an amino acid residue,

m is 1 or 2, and

n is an integer of 0-2, with the proviso that when n is 0, R 3 is hydrogen or alkyl,

or a pharmaceutically acceptable salt thereof.

2. The compound of claim 1 , or a pharmaceutically acceptable salt thereof,

wherein said substituted alkylcarbonylamino represented by R 3 is alkylcarbonylamino substituted by one or two substituent group selected from the group consisting of carboxy, amino, alkylamino and dialkylamino.

3. The compound of claim 1 , or a pharmaceutically acceptable salt thereof,

wherein R 3 is hydrogen or a group of formula (3):

wherein r is an integer of 1-3, and

R 4 is carboxy or a group of formula (2′):

wherein W′ is a glycine residue or β-alanine residue.

4. The compound of claim 3 , or a pharmaceutically acceptable salt thereof,

wherein R 3 is a group of formula (3′):

R 4 is carboxymethylcarbamoyl.

5. The compound of claim 3 , or a pharmaceutically acceptable salt thereof,

wherein R 3 is hydrogen and R 4 is carboxy.

6. A compound of formula (1′):

wherein X′ is a tyrosine residue or a methionine residue,

R 1′ is hydrogen or alkyl,

R 2′ is hydroxyl, amino, alkylamino or dialkylamino,

R 3′ is amino, alkylamino, dialkylamino or substituted or unsubstituted alkylcarbonylamino, and

R 4′ is carboxy, carbamoyl, alkylcarbamoyl or dialkylcarbamoyl,

or a pharmaceutically acceptable salt thereof.

7. An antigen-presenting cell on which a complex between the compound of claim 1 or a pharmaceutically acceptable salt thereof and HLA-A24 antigen is present.

8. The antigen presenting cell of claim 7 , which is a dendritc cell.

9. A pharmaceutical composition comprising the compound of claim 1 or a pharmaceutically acceptable salt thereof in combination with a pharmaceutically acceptable carrier.

10. The compound of claim 1 which is of formula (4):

or a pharmaceutically acceptable salt thereof.

11. The compound of claim 1 which is of formula (5):

or a pharmaceutically acceptable salt thereof.