Santana-Rivera Yasmarie, Rabelo-Fernández Robert J, Quiñones-Díaz Blanca I, Grafals-Ruíz Nilmary, Santiago-Sánchez Ginette, Lozada-Delgado Eunice L, Echevarría-Vargas Ileabett M, Apiz Juan, Soto Daniel, Rosado Andrea, Meléndez Loyda, Valiyeva Fatima, Vivas-Mejía Pablo E
Department of Interdisciplinary Sciences, University of Puerto Rico, Rio Piedras Campus San Juan 00927, Puerto Rico.
Comprehensive Cancer Center, University of Puerto Rico, Medical Sciences Campus San Juan 00935, Puerto Rico.
Am J Transl Res. 2020 Apr 15;12(4):1275-1292. eCollection 2020.
Despite good responses to first-line treatment with platinum-based combination chemotherapy, most ovarian cancer patients will relapse and eventually develop a platinum-resistant disease with a poor overall prognosis. The molecular events leading to the cisplatin resistance of ovarian cancer cells are not fully understood. Here, we performed a proteomic analysis to identify protein candidates deregulated in a cisplatin-resistant ovarian cancer cell line (A2780CP20) in comparison to their sensitive counterpart (A2780). Forty-eight proteins were differentially abundant in A2780CP20, as compared with A2780, cells. Enolase-1 (ENO1) was significantly decreased in cisplatin-resistant ovarian cancer cells. Western blots and RT-PCR confirmed our findings. Ectopic ENO1 expression increased the sensitivity of ovarian cancer cells to cisplatin treatment. In contrast, small-interfering (siRNA)-based ENO1 silencing in A2780 cells reduced the sensitivity of these cells to cisplatin treatment. Whereas glucose consumption was lower, intracellular levels were higher in cisplatin-resistant ovarian cancer cells as compared with their cisplatin-sensitive counterparts. Senescence-associated β-galactosidase (β-Gal) levels were higher in cisplatin-resistant ovarian cancer cells as compared with cisplatin-sensitive ovarian cancer cells. β-Gal levels were decreased in ENO1 overexpressed clones. Protein levels of the cell cycle regulators and senescence markers p21 and p53 showed opposite expression patterns in cisplatin-resistant compared with cisplatin sensitive cells. Our studies suggest that decreased expression of ENO1 promotes glucose accumulation, induces senescence, and leads to cisplatin resistance of ovarian cancer cells.
尽管卵巢癌患者对铂类联合化疗一线治疗反应良好，但大多数患者仍会复发，最终发展为铂耐药疾病，总体预后较差。导致卵巢癌细胞顺铂耐药的分子机制尚未完全明确。在此，我们进行了蛋白质组学分析，以鉴定与敏感的卵巢癌细胞系（A2780）相比，在顺铂耐药的卵巢癌细胞系（A2780CP20）中表达失调的蛋白质候选物。与A2780细胞相比，A2780CP20中有48种蛋白质丰度存在差异。在顺铂耐药的卵巢癌细胞中，烯醇化酶-1（ENO1）显著降低。蛋白质免疫印迹法和逆转录-聚合酶链反应证实了我们的发现。异位表达ENO1可增加卵巢癌细胞对顺铂治疗的敏感性。相反，在A2780细胞中基于小干扰RNA（siRNA）的ENO1沉默降低了这些细胞对顺铂治疗的敏感性。与顺铂敏感的卵巢癌细胞相比，顺铂耐药的卵巢癌细胞葡萄糖消耗较低，但细胞内水平较高。与顺铂敏感的卵巢癌细胞相比，顺铂耐药的卵巢癌细胞衰老相关β-半乳糖苷酶（β-Gal）水平更高。在ENO1过表达的克隆中，β-Gal水平降低。与顺铂敏感细胞相比，顺铂耐药细胞中细胞周期调节因子和衰老标志物p21和p53的蛋白质水平呈现相反的表达模式。我们的研究表明，ENO1表达降低促进葡萄糖积累，诱导衰老，并导致卵巢癌细胞顺铂耐药。
