背景:膀胱癌(BC)是最常见的泌尿道恶性肿瘤。极光激酶B(AURKB),染色体乘客蛋白复合体的一个组成部分,影响细胞分裂过程中的染色体分离。有丝分裂阻滞缺陷型2样蛋白2(MAD2L2)与各种蛋白质相互作用,并有助于基因组完整性。AURKB和MAD2L2在各种人类癌症中都过表达,并具有协同致癌作用;因此,它们被认为是癌症的新兴治疗靶点。然而,这些因素与其在BC中致癌活性的潜在机制之间的关系仍然未知。本研究旨在探讨AURKB和MAD2L2之间的相互作用以及它们如何通过DNA损伤反应(DDR)途径影响BC的进展。
方法:使用生物信息学分析表达,预后价值,BC患者AURKB的前肿瘤功能。CCK-8测定,集落形成试验,流式细胞术,SA-β-gal染色,伤口愈合试验,并进行了transwell小室实验以测试其生存能力,细胞周期进程,衰老,BC细胞的迁移和侵袭能力。进行裸鼠异种移植物测定以测试BC细胞在体内的肿瘤发生能力。蛋白质的表达和相互作用以及衰老相关分泌表型的发生采用westernblot分析,免疫共沉淀试验,和RT-qPCR。
结果:AURKB在BC患者中高表达并与预后相关。AURKB表达与MAD2L2表达呈正相关。我们确认AURKB与,并调制的表达式,BC细胞中的MAD2L2。AURKB敲除抑制了扩散,迁移,和入侵能力,和细胞周期进程,BC细胞,诱导这些细胞衰老。在体外和体内通过MAD2L2过表达挽救了AURKB敲低的作用。MAD2L2敲低的效果与AURKB敲低的效果相似。此外,p53消融挽救了MAD2L2敲低诱导的BC细胞增殖抑制以及BC细胞的细胞周期停滞和衰老。
结论:AURKB激活MAD2L2表达下调p53DDR通路,从而促进BC进展。因此,AURKB可能作为一种潜在的分子标志物和新型的BC抗癌治疗靶点。
Bladder cancer (BC) is the most common urinary tract malignancy. Aurora kinase B (AURKB), a component of the chromosomal passenger protein complex, affects chromosomal segregation during cell division. Mitotic arrest-deficient 2-like protein 2 (MAD2L2) interacts with various proteins and contributes to genomic integrity. Both AURKB and MAD2L2 are overexpressed in various human cancers and have synergistic oncogenic effects; therefore, they are regarded as emerging therapeutic targets for cancer. However, the relationship between these factors and the mechanisms underlying their oncogenic activity in BC remains largely unknown. The present study aimed to explore the interactions between AURKB and MAD2L2 and how they affect BC progression via the DNA damage response (DDR) pathway.
Bioinformatics was used to analyze the expression, prognostic value, and pro-tumoral function of AURKB in patients with BC. CCK-8 assay, colony-forming assay, flow cytometry, SA-β-gal staining, wound healing assay, and transwell chamber experiments were performed to test the viability, cell cycle progression, senescence, and migration and invasion abilities of BC cells in vitro. A nude mouse xenograft assay was performed to test the tumorigenesis ability of BC cells in vivo. The expression and interaction of proteins and the occurrence of the senescence-associated secretory phenotype were detected using western blot analysis, co-immunoprecipitation assay, and RT-qPCR.
AURKB was highly expressed and associated with prognosis in patients with BC. AURKB expression was positively correlated with MAD2L2 expression. We confirmed that AURKB interacts with, and modulates the expression of, MAD2L2 in BC cells. AURKB knockdown suppressed the proliferation, migration, and invasion abilities of, and cell cycle progression in, BC cells, inducing senescence in these cells. The effects of AURKB knockdown were rescued by MAD2L2 overexpression in vitro and in vivo. The effects of MAD2L2 knockdown were similar to those of AURKB knockdown. Furthermore, p53 ablation rescued the MAD2L2 knockdown-induced suppression of BC cell proliferation and cell cycle arrest and senescence in BC cells.
AURKB activates MAD2L2 expression to downregulate the p53 DDR pathway, thereby promoting BC progression. Thus, AURKB may serve as a potential molecular marker and a novel anticancer therapeutic target for BC.