NF-kB转录活化miR-130b协同促进PKCα促膀胱癌细胞存活机制的研究

Aberrant activation of PKC has been shown to promote the development of malignant tumors including bladder cancer, which is the most diagnosed urologic maligance in Chinese. We previously found that PKCα was over-activated in bladder cancer and kidney cancer, and its activation was relatd to multidrug resistance in bladder tumor. To extend our study on the functional role of PKCα signaling in cancer development and progression, we recently secreening the potential downstream targets following activation of PKCα in bladder cancer cells by mRNA microarray and miRNA microarray. As expected, PKCα activation induced gene expressions that were related to NF-κB signaling pathway. At the same time, we found a panel of miRNAs also markedly alterated upon the activation of PKCα, especially for miR-130b, which has been associated with an oncogenic role in many cancers. Given the fact that miR-130b was found to be co-expressed with PKC α/NF-κB in the bladder cancer tissues in our preliminary work, and the fact that the promoter region of miR-130b contains NF-κB binding site, we hypothesize that NF-κB could regulate the transcription of miR-130b and facilitate PKC α signaling to promote the development and progression of bladder cancer. To fulfil this purpose, we propose to study the regulation of miR-130b transcription by NF-κB that is triggered by PKCα signaling pathway by using luciferase assay, chromatin immunoprecipitation, in vitro functional experiment and nude mice implantation assay. The successful completion of the proposed study may uncover a new mechanism underling the promotive effect of PKCα signaling on the development and progression of bladder cancer, and provide us new targets for cancer therapy.

泌尿系肿瘤中蛋白激酶C（PKC）的异常活化是促进肿瘤恶性进展的分子机制之一。我们的前期研究发现，PKC α在活化经典NF-κB 通路的同时，也明显上调了内源性miRNA-130b-一个具有癌基因功能的微小RNA 的表达。结合膀胱癌标本中miRNA-130b 的表达与PKC α/NF-κB 表达的相关趋势及miRNA-130b 转录调控区含有NF-κB结合位点的生物信息学分析结果，本课题拟通过报告基因分析、染色体免疫沉淀，体外功能实验及裸鼠种植实验等方法，力图证实：NF-κB直接上调miRNA-130b的转录，参与了PKCα对膀胱癌生物行为学恶性进展的促进作用。本项目的顺利完成将揭示一条PKCα调节肿瘤功能的新途径，为有效治疗浸润性膀胱癌提供新的靶点。

泌尿系肿瘤中蛋白激酶C（PKC）及NF-κ B的异常活化是促进肿瘤恶性进展的分子机制之一。我们的前期研究发现，PKC α 在活化经典NF-κ B 通路的同时，也明显上调了内源性miRNA-130b—一个具有癌基因功能的微小RNA 的表达。结合膀胱癌标本中miRNA-130b 的表达与PKC α /NF-κ B 表达的相关趋势及miRNA-130b 转录调控区含有NF-κ B 结合位点的生物信息学分析结果，本课题通过报告基因分析、染色体免疫沉淀，体外功能实验及裸鼠种植实验等方法，有力证实：1.miR-130b在膀胱癌中的癌基因（onco-miRNA）作用；2.NF-kB信号通路可直接调控miR-130b表达；3.PKC α调节NFkB通路；4.PKC α-NF-kB-miR-130b信号轴具有重要的癌生物学功能。本项目的顺利完成将揭示一条PKC α-NF-kB-miR-130b调节肿瘤功能的新途径，为有效治疗浸润性膀胱癌提供新的靶点。