Stabilized stat3 decoy oligonucleotides and uses therefore

Abstract

The present invention is based, at least in part, on novel, unimolecular STAT3 oligonucleotide decoys exhibiting increased in vivo stability as compared to previously known decoys which are effective in inhibiting STAT3 when administered systemically. The invention is also based on pharmaceutical compositions comprising these unimolecular decoys, and methods for using these decoys in the treatment of cancer.

We claim: 
     
         1 . A double-stranded STAT3 oligonucleotide decoy, comprising a derivative of the STAT3 target sequence: (5′-(N 6 ) n -CATTTCCCGTAAATC-(N 7 ) m -3′, (SEQ ID NO:2), in which N 6  and N 7  are A, T, G or C and n and m are independently 0-50, containing a single nucleotide insertion or substitution within the sequence 5′-CATTTCCCGTAAATC-3′ (SEQ ID NO:30), wherein the decoy comprises an oligonucleotide that binds to STAT3 protein and is effective in inhibiting growth of a cancer in which STAT3 is activated when administered systemically to a subject, and wherein the decoy has a serum half-life of greater than about 1.5 hours. 
     
     
         2 . The STAT3 oligonucleotide decoy of  claim 1 , wherein the decoy has a unimolecular duplex structure. 
     
     
         3 . The STAT3 oligonucleotide decoy of  claim 2 , wherein the decoy comprises at least one phosphorothioated nucleotide. 
     
     
         4 . The STAT3 oligonucleotide decoy of  claim 3 , wherein the two strands are linked at one end by a hairpin. 
     
     
         5 . The STAT3 oligonucleotide decoy of  claim 4 , wherein the hairpin consists of four nucleotides. 
     
     
         6 . The STAT3 oligonucleotide decoy of  claim 5 , wherein the decoy comprises at least three phosphorothioated nucleotide at the 5′ end of one strand the 3′ end of the other strand. 
     
     
         7 . The STAT3 oligonucleotide decoy of  claim 6 , wherein the decoy comprises three phosphorothioate modifications at the 5′ and 3′ end of both strands. 
     
     
         8 . The STAT3 oligonucleotide decoy of  claim 2 , wherein the two strands are linked at one end by a carbon spacer. 
     
     
         9 . The STAT3 oligonucleotide decoy of  claim 8 , wherein the carbon spacer is a 18-atom hexa-ethyleneglycol (C-18) spacer. 
     
     
         10 . The STAT3 oligonucleotide decoy of  claim 8 , wherein the decoy comprises three phosphorothioated nucleotides at the 5′ end of one strand and three phosphorothioated nucleotides at the 3′ end of the other strand. 
     
     
         11 . The STAT3 oligonucleotide decoy of  claim 2 , wherein the decoy comprises at least one locked nucleic acid (LNA) at the 5′ end of one strand and at least one LNA at the 3′ end of the other strand. 
     
     
         12 . The STAT3 oligonucleotide decoy of  claim 11 , wherein the two strands are linked at one end by a carbon spacer or a hairpin. 
     
     
         13 . The STAT3 oligonucleotide decoy of  claim 1 , wherein the decoy is a cyclic oligonucleotide. 
     
     
         14 . The STAT3 oligonucleotide decoy of  claim 13 , wherein the two strands are linked by C-18 spacers at both ends. 
     
     
         15 . The STAT3 oligonucleotide decoy of  claim 13 , wherein the 5′ end of the sense strand and the 3′ end of the antisense strands are linked with LP1a and LP1b spacers and the 3′ end of the sense strand and the 5′ end of the antisense strands are linked by an LP2 spacer. 
     
     
         16 . The STAT3 oligonucleotide decoy of  claim 13 , wherein at least one polyunsaturated fatty acid is covalently linked to the decoy. 
     
     
         17 . The STAT3 oligonucleotide decoy of  claim 1 , wherein the STAT3 decoy comprises CAN 1 TTCN 2 CN 3 TN 4 AN 5 TC-(N 7 -) m -3′, (SEQ ID NO:1), wherein N 1 , N 2 , N 3 , N 4  and N 5  are A, T, G or C, and one, two, three or all of the following conditions are met: N 1 , is T; N 2  is C; N 3  is G, N 4  is A and N 5  is A, and N 6  and N 7  are A, T, G or C and n and m are independently 0-50. 
     
     
         18 . The STAT3 oligonucleotide decoy of  claim 17 , wherein N 2  is a pyrimidine. 
     
     
         19 . The STAT3 oligonucleotide decoy of  claim 17 , wherein at least two of the following are met: N 1 , is T; N 2  is C; N 3  is G, N 4  is A and N 5  is A. 
     
     
         20 . The STAT3 oligonucleotide decoy of  claim 17 , wherein at least three of the following are met: N 1 , is T; N 2  is C; N 3  is G, N 4  is A and N 5  is A. 
     
     
         21 . The STAT3 oligonucleotide decoy of  claim 17 , wherein N 3  is G. 
     
     
         22 . A pharmaceutical composition comprising the STAT3 oligonucleotide decoy of  claim 1  and a pharmaceutically acceptable carrier. 
     
     
         23 . The pharmaceutical composition of  claim 23 , further comprising an anticancer agent. 
     
     
         24 . The composition of  claim 22 , formulated as a parenteral dosage form. 
     
     
         25 . The composition of  claim 24 , formulated as an intravenous dosage form. 
     
     
         26 . The composition of  claim 22 , wherein the decoy is contained within a microbubble. 
     
     
         27 . The composition of  claim 22 , wherein the decoy is associated with a peptide transduction domain. 
     
     
         28 . The composition of  claim 27 , wherein the peptide transduction domain is TAT. 
     
     
         29 . A method of inhibiting growth of a cancer in which STAT3 is activated in a patient, comprising administering to the patient an amount of the STAT3 oligonucleotide decoy of  claim 1  effective to inhibit growth of a cancer in a patient, thereby inhibiting growth of the cancer in the patient. 
     
     
         30 . The method of  claim 29 , wherein the cancer is a squamous cell carcinoma. 
     
     
         31 . The method of  claim 30 , wherein the cancer is a squamous cell carcinoma of the head and neck. 
     
     
         32 . The method of  claim 29 , comprising administering to the patient a second anticancer therapy. 
     
     
         33 . The method of  claim 32 , wherein the second anticancer therapy is one or both of a radiation therapy and treating the patient with an anticancer agent. 
     
     
         34 . The method of  claim 32 , wherein the second anticancer therapy is a radiation therapy. 
     
     
         35 . The method of  claim 32 , wherein the second anticancer therapy comprises treating the patient with an anticancer agent. 
     
     
         36 . The methods of  claim 32 , wherein the anticancer therapy is an epidermal growth factor receptor (EGFR) antagonist. 
     
     
         37 . The method of  claim 36 , wherein the epidermal growth factor receptor (EGFR) antagonist is cetuximab. 
     
     
         38 . The method of  claim 29 , wherein the cancer is selected from the group consisting of multiple myeloma, HTLV-1 dependent leukemia, acute myelogenous leukemia, large granular lymphocyte leukemia, lymphoma, EBV-related Burkitt's lymphoma, mycosis fungoides, cutaneous T-cell lymphoma, non-Hodgkins lymphoma, anaplastic large-cell lymphoma, breast cancer, melanoma, ovarian cancer, lung cancer, pancreatic cancer, and prostate cancer.