YAP调控代谢共生体代谢改变与上皮性卵巢癌化疗耐受及机制研究

The drug resistance mechanisms of epithelial ovarian cancers is multiplex. The cancer cells and adjacent cancer-associated fibroblasts appears that metabolic interplay might give rise to induce metabolic symbiont. As such, metabolic symbiont undergo aerobic glycolysis due to autophagy stress. In turn, a L-lactate shuttle between metabolic symbiont can be the fuels and plays a role in the progression of cancer cells. YAP, the key transcriptional target of the Hippo pathway, plays a conserved role in promoting tumorigenesis in human cancers. The recent data indicates that the YAP pathway plays a role in integrating the processes of autophagy dur¬ing cellular stress. YAP activation is one of feature of cancer-associated fibroblasts. Inhibition of glucose metabolism could inhibit YAP activity. Much of the current studies also elucidate the oncogenic role of YAP in promoting aerobic glycolysis. When glucose metabolism is blocked, or aerobic glycolysis is reduced, YAP transcriptional activity is decreased. And our previous research found that YAP- mediated autophagy may play a protective role in cisplatin-resistant human ovarian cancer cells. Based on epithelial ovarian cancer cell and CAFs co-cluture, a metabolic symbiont was set up in vitro. Thus, we focus on investigate the role of the metabolic alteration in metabolic symbiont medicated by YAP and the chemoresistance in epithelial ovarian cancer. The related mechanisms about it is invovled in the study. This should be provide a promising news trategies for recovery the epithelial ovarian cancer cells chemosensitivity by block the energy transfer and the transcript of growth gene through impacting on metabolic alteration in metabolic symbiont.

上皮性卵巢癌通过多种机制产生耐药。研究表明癌细胞与毗邻肿瘤相关成纤维细胞(CAFs)因代谢互补成为代谢共生体(metabolic symbiont)，自噬诱导其发生异常糖酵解，在代谢共生体间形成一个乳酸穿梭，乳酸被用作支持肿瘤细胞倍增的能量来源。YAP是Hippo通路关键转录共激活因子，参与肿瘤发生发展，并与调控自噬有关。YAP活化是CAFs特征之一，代谢途径可调节YAP活性，异常糖酵解有助于维持YAP活性及其致癌功能。在本人前期研究YAP介导自噬与上皮性卵巢癌顺铂耐药的基础上，本课题采用上皮性卵巢癌细胞与其CAFs共培养，体外模拟代谢共生体。通过证实YAP在调控肿瘤代谢共生体代谢转变中的作用，以全新思路探讨上皮性卵巢癌化疗耐受与能量代谢的关系及其分子机制，拟通过切断这种代谢共生体代谢转变带来的能量传递及生长基因转录，恢复上皮性卵巢癌化疗敏感性，为逆转上皮性卵巢癌化疗耐受提供了一个新方向。

CAFs是肿瘤微环境中重要细胞成分，YAP是维持上皮性卵巢癌代谢共生体的主体—CAFs的关键因素。空泡型质子泵(V-ATPase)在肿瘤酸性微环境调节中发挥了重要作用。上皮性卵巢癌组织过表达V-ATPase，我们前期研究证实YAP与V-ATPase表达有相关性，敲低卵巢癌耐药细胞中V-ATPase，YAP表达亦下降，提示V-ATPase可调控YAP表达。本研究针对上皮性卵巢癌及其代谢共生体中异常糖酵解导致的肿瘤酸性微环境，运用V-ATPase抑制剂PPI探讨其对上皮性卵巢癌及其代谢共生体肿瘤酸性微环境、自噬及YAP与上皮性卵巢癌化疗耐受的影响及其作用机制。质子泵抑制剂奥美拉唑(EMSO)可抑制V-ATPase逆转细胞内外PH梯度，与单用紫杉醇比较联合大剂量EMSO可显著抑制耐药细胞增殖、细胞对紫杉醇敏感性恢复、细胞自噬减少、Caspase-3/8通路依赖细胞凋亡增加；总结其作用机制与EMSO抑制细胞V-ATPase，下调细胞YAP表达，逆转了肿瘤细胞酸性微环境，进而抑制细胞保护性自噬、促进细胞凋亡有关。在糖尿病患者中，降糖药联合质子泵抑制剂治疗可明显降低血糖和糖化血红蛋白水平，其机制可能与质子泵抑制剂升高胃泌素水平以及生长抑素的分泌增加有关。于是我们比较高糖和低糖培养条件下上皮性卵巢癌共培养细胞中YAP表达，发现高糖培养条件YAP表达明显高于低糖培养条件，EMSO致YAP表达下降并使YAP维持的CAFs失活，代谢共生体间反向Warburg效应受到抑制，从而逆转了肿瘤酸性微环境。本课题从一个实用角度开启逆转上皮性卵巢癌化疗耐受的新方法，具有十分乐观的临床转化应用前景。