ALKYLATING & CLEAVING ANTIC-MYC DNAS FOR BREAST CANCER

烷基化

• 批准号: 2852537
• 负责人: ERIC WICKSTROM
• 金额: $ 3.87万
• 依托单位: THOMAS JEFFERSON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-07-01 至 2002-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2852537
• 关键词: DNA; MCF7 cell; alkylation; antisense nucleic acid; bleomycin; breast neoplasms; cell line; cell proliferation; chemical cleavage; gene expression; gene therapy; genetic promoter element; laboratory mouse; natural gene amplification; neoplastic cell; nucleic acid sequence; oligonucleotides; protooncogene; tissue /cell culture; tissue mosaicism; xenotransplantation

Breast cancer attacks one out of every nine women. Among the many indicators and prognostic factors in breast cancer, the c- MYC proto-oncogene is amplified and overexpressed in many early and advanced stage mammary tumors. Antisense DNA therapy is proving effective in human clinical trials against viruses and oncogenes. Nuclease resistant reactive oligonucleotides offer powerful tools for intervention against malignant cells with activated oncogenes. The hypothesis of this proposal is that oligonucleotide therapy will achieve antiproliferative potency by specifically ablating c-MYC overexpression in breast cancer cells at subtoxic doses. For this purpose, the Novosibirsk laboratory will synthesize alkylating [4-(N-2-chloroethyl, N-methylamino) benyzylmethylamino] and cleaving (bleomycin A5) derivatives of nuclease resistant phosphorothioate DNAs, 2'-O-methyl RNAs, and their chimeras, potentiated with phenazinium and/or steroid modifications, targeted against c-MYC mRNA targets. The unique heterobifunctional oligonucleotide derivatives with 3'- cholesterol and 5'-reactive groups efficiently penetrate into cells, resist intracellular nucleases, and modify nucleic acids site-specifically. The Novosibirsk laboratory will also synthesize bleomycin A5 derivatives of nuclease resistant triplex-forming DNAs, potentiated with phenazinium and/or steroid modifications, targeted against c-myc DNA oligopurine promoter sequences. The Philadelphia laboratory will test the antigen reduction and antiproliferative efficacy of the reactive oligonucleotides in a tumorigenic human breast cancer cell line, BT474, which overexpresses c-MYC, compared with MCF7 cells, which do not overexpress c-MYC without estrogen stimulation. This new joint effort has been initiated by the visit of Dr. Smith to the Novosibirsk laboratory to measure anti-c-MYC bleomycin A5 oligomer reactivity with c-MYC RNA. In future years, the most potent nuclease resistant reactive oligonucleotides determined in cell culture will then be tested for preclinical potency by measuring inhibition of tumor growth in nude mice due to subcutaneous implantation of the BT474 and MCF7 cell lines.

乳腺癌每9名女性中就有1名罹患。 在乳腺癌的许多指标和预后因素中，c-MYC原癌基因在许多早期和晚期乳腺肿瘤中扩增和过表达。 反义DNA疗法在人类临床试验中被证明对病毒和癌基因有效。 核酸酶抗性反应性寡核苷酸为干预具有激活的癌基因的恶性细胞提供了强有力的工具。 该建议的假设是，寡核苷酸治疗将通过在亚毒性剂量下特异性消除乳腺癌细胞中的c-MYC过表达来实现抗增殖效力。为此，新西伯利亚实验室将合成抗核酸酶硫代磷酸酯DNA、2 '-O-甲基RNA及其嵌合体的烷基化[4-（N-2-氯乙基，N-甲氨基）苄基甲氨基]和裂解（博来霉素A5）衍生物，通过吩嗪鎓和/或类固醇修饰增强，靶向c-MYC mRNA靶标。 具有3 '-胆固醇和5'-反应性基团的独特异双功能寡核苷酸衍生物有效地渗透到细胞中，抵抗细胞内核酸酶，并位点特异性地修饰核酸。 新西伯利亚实验室还将合成博莱霉素A5衍生物的核酸酶抗性三链体形成DNA，增强与吩嗪和/或类固醇修饰，针对c-myc DNA寡嘌呤启动子序列。 费城实验室将在致瘤性人乳腺癌细胞系BT474中测试反应性寡核苷酸的抗原减少和抗增殖功效，BT474过表达c-MYC，而MCF 7细胞在没有雌激素刺激的情况下不过表达c-MYC。这项新的联合工作是由Smith博士访问新西伯利亚实验室以测量抗c-MYC博莱霉素A5寡聚体与c-MYC RNA的反应性而发起的。 在未来几年中，将通过测量皮下植入BT474和MCF 7细胞系对裸鼠肿瘤生长的抑制作用，检测细胞培养物中测定的最有效的核酸酶抗性反应性寡核苷酸的临床前效力。