Abstract：
Epithelial ovarian cancer (EOC) is the most lethal gynaecological malignancy with poor prognosis and dismal patient survival. Although protein kinase D (PKD) isoforms, especially PKD2 and PKD3 are critical for many cellular and physiological functions involved in carcinogenesis including cell proliferation and angiogenesis, their role in human EOC remains unknown. Towards the goal to identify novel prognostic biomarker and therapeutic interventions against EOC, this study aimed to elucidate the molecular roles of PKD2, PKD3 and highly selective, pan-PKD inhibitor CRT0066101 in this lethal pathology. Our results indicated that inactivation of PKD2 and PKD3 by 1 μM CRT0066101 suppressed EOC cell proliferation, colony formation, cell migration and invasion. Moreover, CRT0066101 induced apoptosis and inhibited cell cycle at G2-M phase in EOC cells. Genetic knockdown of PKD2 and PKD3 confirmed the anti-carcinogenic effects of CRT0066101 against EOC. The anti-cancer phenotype of EOC cells resulted from CRT0066101-mediated PKD2 and PKD3 inactivation or genetic depletion was, in part, mediated by transcription factor Runx2 as abrogation of PKD2 and PKD3 caused downregulation of Runx2 and its downstream target genes including osteopontin, focal adhesion kinase and ERK1/2. Moreover, overexpression of a constitutively active PKD2 augmented the expression levels of phosphor-ERK1/2T202/Y204, Runx2 and its downstream targets. Mechanistically, PKD2 and PKD3 positively regulated Runx2 via MAPK/ERK1/2 pathway and promoted EOC. Taken together, our results indicated that PKD2/3/ERK1/2/Runx2 signalling axis might be a novel drug target against EOC and CRT0066101 could be developed as a promising therapeutic choice against this lethal pathology.
摘要：
上皮性卵巢癌（EOC）是最致命的妇科恶性肿瘤，预后差，患者生存率低。虽然蛋白激酶D（PKD）亚型，特别是PKD2和PKD3对于许多参与癌变的细胞和生理功能至关重要，包括细胞增殖和血管生成。它们在人类EOC中的作用仍然未知。为了确定针对EOC的新型预后生物标志物和治疗干预措施，本研究旨在阐明PKD2、PKD3的分子作用,pan-PKD抑制剂CRT0066101在这种致命病理中。我们的结果表明，1μMCRT0066101对PKD2和PKD3的失活抑制了EOC细胞的增殖，菌落形成,细胞迁移和侵袭。此外，CRT0066101在EOC细胞中诱导凋亡并在G2-M期抑制细胞周期。PKD2和PKD3的基因敲低证实了CRT0066101对EOC的抗癌作用。由CRT0066101介导的PKD2和PKD3失活或遗传耗竭导致的EOC细胞的抗癌表型是，在某种程度上,转录因子Runx2介导的PKD2和PKD3的废除引起Runx2及其下游靶基因包括骨桥蛋白的下调,粘着斑激酶和ERK1/2。此外，组成型活性PKD2的过表达增加了磷ERK1/2T202/Y204，Runx2及其下游靶标的表达水平。机械上,PKD2和PKD3通过MAPK/ERK1/2通路正向调节Runx2并促进EOC。一起来看,我们的结果表明,PKD2/3/ERK1/2/Runx2信号轴可能是针对EOC的新的药物靶点,CRT0066101可被开发为针对这种致死性病理的有前景的治疗选择.
