LncRNA LOC283070抑制PHB2激活AR信号通路促进前列腺癌转型的机制

The transformation from androgen-dependent prostate cancer to androgen-independent prostate cancer is a key problem for study of prostate cancer, the role of lncRNA in the transition is rarely reported. We established androgen-independent LNCaP-AI cells with androgen-dependent prostate cancer cell line LNCaP, and screened the differentially expressed lncRNAs. It was found that LOC283070 could promote the proliferation and migration of prostate cancer cells and promote its transformation. Biotin-RNA pull down experiment found that LOC283070 can bind PHB2 protein, It was reported that down-regulation of PHB protein can activate AR signaling pathway to promote prostate cancer transformation, PHB2 belongs to PHB protein family. We speculate that LOC283070 can promote the transformation of prostate cancer by inhibiting PHB2 to activate AR signaling pathway. On the basis of the following studies: Our group will explore the mechanism of LOC283070 in the regulation of PHB2 activation of AR signaling pathway to promote the transformation of prostate cancer on cell level; Nude mice transplant tumor model will be used to further explore the mechanism of LOC283070 inhibition of PHB2 to promote the transformation of prostate cancer;clinical specimens of prostate cancer will be collected to validate the correlation between LOC283070, PHB2 and prostate cancer. As to provide theoretical basis for controlling the transition of prostate cancer.

前列腺癌由雄激素依赖向非依赖转型的机制是前列腺癌研究的难点，而lncRNA在转型中的作用报道不多。我们利用雄激素依赖的前列腺癌细胞LNCaP建立了非依赖的LNCaP-AI细胞,筛选二者差异表达的lncRNA后，发现LOC283070可促进前列腺癌细胞的增殖、迁移进而促进其转型，Biotin-RNA pull down实验发现LOC283070可结合PHB2蛋白。文献报道下调PHB蛋白可激活AR信号通路促进前列腺癌转型，PHB2属于PHB蛋白家族。我们推测LOC283070可通过抑制PHB2激活AR信号通路促进前列腺癌转型。在此基础上做以下研究：细胞水平研究LOC283070抑制PHB2激活AR信号通路促进前列腺癌转型的机制；裸鼠成瘤模型进一步探究LOC283070抑制PHB2促进前列腺癌转型的机制；临床标本验证LOC283070、PHB2与前列腺癌的相关性。为控制前列腺癌转型提供理论依据。

前列腺癌由激素依赖向非依赖转型的研究很多，但lncRNA在转型中的作用鲜有报道。我们利用激素依赖的前列腺癌细胞LNCaP建立了激素非依赖的LNCaP-AI细胞,比较二者lncRNA表达谱的差异后，发现LOC283070可促进细胞的增殖、转移，在LNCaP细胞激素非依赖转型中发挥重要作用，且LOC283070可能通过与PHB2蛋白相互作用。本项目通过Bio-RNA pull down实验及RIP实验明确了LOC283070与PHB2结合的特异性，且发现LOC283070与PHB2结合不影响PHB2的表达，进一步的，通过双荧光素报告酶实验发现PHB2可抑制AR信号通路活性。我们通过细胞实验发现PHB2可抑制细胞的增殖与转移，而LOC283070可通过与PHB2结合抑制其发挥作用；进一步进行动物实验：建立稳定转染LOC283070的细胞系，在正常/去势裸鼠体内建立异位移植瘤研究肿瘤生长的变化，发现在正常/去势裸鼠LOC283070都能明显促进前列腺癌细胞增殖；从而明确了LOC283070通过抑制PHB2蛋白功能，进而激活AR信号通路在前列腺癌由激素依赖到非依赖转型演进过程中的生物学作用和分子机制。本项目的研究成果为激素非依赖前列腺癌 (AIPC)转型的机制研究提供新的理论依据。