Compositions comprising MIR34 therapeutic agents for treating cancer

1. An isolated synthetic duplex microRNA mimetic comprising:

(i) a guide strand nucleic acid molecule consisting of a nucleotide sequence of 18 to 25 nucleotides, said guide strand nucleotide sequence comprising a seed region nucleotide sequence and a non-seed region nucleotide sequence, said seed region consisting of nucleotide positions 1 to 12 and said non-seed region consisting of nucleotide positions 13 to the 3′ end of said guide strand, wherein position 1 of said guide strand represents the 5′ end of said guide strand, wherein said seed region comprises a consecutive nucleotide sequence of at least 6 nucleotides that is identical to a seed region sequence of a naturally occurring microRNA; and

(ii) a passenger strand nucleic acid molecule consisting of a nucleotide sequence of 18 to 25 nucleotides, said passenger strand comprising a nucleotide sequence that is essentially complementary to the guide strand, wherein said passenger strand nucleic acid molecule has one nucleotide sequence difference compared with the true reverse complement of the seed region of the guide strand, wherein the one nucleotide difference is located within nucleotide position 13 to the 3′ end of the passenger strand.

2. The isolated synthetic duplex microRNA mimetic of claim 1 , wherein the guide strand comprises a seed region comprising a consecutive nucleotide sequence of at least 6 nucleotides that is identical in sequence to a nucleotide sequence selected from the group consisting of SEQ ID NO:3, SEQ ID NO:6, SEQ ID NO:9 and SEQ ID NO:31.

3. The isolated synthetic duplex microRNA mimetic of claim 1 , wherein said guide strand sequence is selected from the group consisting of miR34a (SEQ ID NO:1), miR34b (SEQ ID NO:4), miR34c (SEQ ID NO:7) and miR449 (SEQ ID NO:29).

4. The isolated synthetic duplex microRNA mimetic of claim 1 , wherein the nucleotide difference in the passenger strand is located within 6 nucleotides of its 3′ end.

5. The isolated synthetic duplex microRNA mimetic of claim 1 , wherein the synthetic duplex further comprises one 3′ overhang, wherein said 3′ overhang comprises from 1 to 4 nucleotides.

6. The isolated synthetic duplex microRNA mimetic of claim 5 , further comprising a second 3′ overhang wherein said second 3′ overhang comprises from 1 to 4 nucleotides.

7. The isolated synthetic duplex microRNA mimetic of claim 1 , wherein said duplex further comprises a non-nucleotide moiety.

8. The isolated synthetic duplex microRNA mimetic of claim 1 , wherein the guide strand and the passenger strand are stabilized against nucleolytic degradation.

9. The isolated synthetic duplex microRNA mimetic of claim 1 , further comprising at least one chemically modified nucleotide or non-nucleotide at the 5′ end and/or 3′ end of the guide strand and the 3′ end of the passenger strand.

10. The isolated synthetic duplex microRNA mimetic of claim 1 , further comprising a phosphorothioate at the first internucleotide linkage at the 3′ end of the passenger strand and the guide strand.

11. The isolated synthetic duplex microRNA mimetic of claim 1 , further comprising a phosphorothioate at the first internucleotide linkage at the 5′ end of the guide stand and the passenger strand, and a phosphorothioate at the first internucleotide linkage at the 3′ end of the guide strand and the passenger sequences.

12. The isolated synthetic duplex microRNA mimetic of claim 1 , further comprising a 2′-modified nucleotide.

13. The isolated synthetic duplex microRNA mimetic of claim 12 , wherein the 2′-modified nucleotide comprises a modification selected from the group consisting of: 2′-deoxy, 2′-deoxy-2′-fluoro, 2′-O-methyl, 2′-O-methoxyethyl (2′-O-MOE), 2′-O-aminopropyl (2′-O-AP), 2′-O-dimethylaminoethyl (2′-O-DMAOE), 2′-O-dimethylaminopropyl (2′-O-DMAP), 2′-O-dimethylaminoethyloxyethyl (2′-O-DMAEOE), and 2′-O—N-methylacetamido (2′-O-NMA).

14. A composition comprising at least one synthetic duplex microRNA mimetic and a delivery agent, the synthetic duplex microRNA mimetic(s) comprising:

(i) a guide strand nucleic acid molecule consisting of a nucleotide sequence of 18 to 25 nucleotides, said guide strand nucleotide sequence comprising a seed region nucleotide sequence and a non-seed region nucleotide sequence, said seed region consisting of nucleotide positions 1 to 12 and said non-seed region consisting of nucleotide positions 13 to the 3′ end of said guide strand, wherein position 1 of said guide strand represents the 5′ end of said guide strand, wherein said seed region further comprises a consecutive nucleotide sequence of at least 6 nucleotides that is identical in sequence to a seed region of a naturally occurring microRNA; and

(ii) a passenger strand nucleic acid molecule comprising a nucleotide sequence of 18 to 25 nucleotides, said passenger strand comprising a nucleotide sequence that is essentially complementary to the guide strand, wherein said passenger strand nucleic acid molecule has one nucleotide sequence difference compared with the true reverse complement sequence of the seed region of the guide strand, wherein the one nucleotide difference is located within nucleotide position 13 to the 3′ end of said passenger strand.

15. The composition of claim 14 , wherein the guide strand comprises a seed region comprising a consecutive nucleotide sequence of at least 6 nucleotides that is identical in sequence to a sequence selected from the group consisting of SEQ ID NO:3, SEQ ID NO:6, SEQ ID NO:9 and SEQ ID NO:31.

16. The composition of claim 14 , wherein said guide strand sequence is selected from the group consisting of miR34a (SEQ ID NO:1), miR34b (SEQ ID NO:4), miR34c (SEQ ID NO:7) and miR449 (SEQ ID NO:29).

17. The composition of claim 14 , wherein the nucleotide difference in the passenger strand is located within 6 nucleotides of its 3′ end.

18. The composition of claim 14 , wherein the delivery agent comprises lipid nanoparticles.