Effects and mechanisms of AMIGO2 in proliferation, migration and drug resistance of bladder cancer

Abstract

Background Bladder cancer is the most common malignancy in urinary system, but the therapeutic targets remain elusive. This study aims to reveal the relationship between AMIGO2 and proliferation, migration, drug-resistance and tumorigenicity of bladder cancer, and explore the potential molecular mechanisms. Methods The expression of AMIGO2 in human bladder cancer tissues is measured by qRT-PCR and immunohistochemistry (IHC). Stable AMIGO2 knockdown cell lines T24 and 5637 were established by lentivirus transfection. Cell viability assay (CCK-8 assay) was used to determine cell proliferation, flow cytometry analysis was utilized to detect cell cycle, and wound healing assay was proceeded to test migration ability of bladder cancer cells. Chemosensitivity to cisplatin was measured by CCK-8 assay. Xenograft mouse model was established for investigating the effect of AMIGO2 on tumor formation in vivo. The RNA Sequencing technology was used to explore differentially expressed genes (DEGs) between knockdown group and negative control group of T24. Bioinformatics analysis upon the results of RNA-Seq was proceeded to understand underlying mechanisms. Results AMIGO2 was upregulated in bladder cancer cells and tissues. Inhibited expression of AMIGO2 suppresses cell proliferation and migration, which might be mediated by cell cycle arrest in G1 phase. AMIGO2 could reduce chemoresistance to cisplatin in bladder cancer cells. Low AMIGO2 expression inhibited tumorigenicity of T24 in nude mice. 917 DEGs were identified by RNA-Sequencing technology and bioinformatics analysis. The DEGs were mainly enriched in cell-cell adhesion, ATP-binding cassette transporters (ABC transporters), PPAR signaling pathway and some other pathways. Among ten hub genes, four of them might be associated with the prognosis of bladder cancer patients. Conclusion AMIGO2 is overexpressed in bladder cancer cells and tissues and serves as an oncogene in bladder cancer. It also reduces chemoresistance to cisplatin. The process might be regulated by particular pathways including ABC transporters and PPAR signaling pathway. Four hub genes might be associated with prognosis of bladder cancer patients.