HEATR3 involved in the cell proliferation, metastasis and cell cycle development of bladder cancer acts as a tumor suppressor

The study was designed to detect the expression and clinical significance of the HEATR3 gene in bladder cancer (BCa) and to preliminarily explore whether this gene can affect the occurrence and development of BCa through the AKT/ERK signaling pathway. The expression and prognostic value of HEATR3 were explored based on The Cancer Genome Atlas (TCGA) and Genotypic Tissue Expression (GTEx) databases. Microarray immunohistochemical analysis was performed in 30 BCa cases to investigate the level of HEATR3 protein and to explore the relationship between HEATR3 and the clinicopathological features of BCa. Western Blot and qRT-PCR were used to detect HEATR3 protein and mRNA in BCa cell lines (5637, TCCSUP, SW780) and fallopian tube epithelial cell (SV-HUC-1). CCK8 method was employed to study the proliferation of BCa cells after heat treatment. Transwell assay was conducted to analyze the effect of HEATR3 on cell migration and invasion. And cell cycle and apoptosis were detected by flow cytometry. Furthermore, Western Blot assay was used to probe the effects of down-regulation of HEATR3 expression on the expression and phosphorylation levels of AKT and ERK proteins in BCa cells. Bioinformatics analysis showed that HEATR3 was significantly up-regulated in BCa, and high HEATR3 expression was associated with poor prognosis of BCa patients. In vitro experiments demonstrated that HEATR3 expression was up-regulated in BCa tissues compared with that in adjacent tissues. HEATR3 protein was also up-regulated in malignant cell lines. HEATR3 knockdown in BCa cells could inhibit cell proliferation, invasion and migration, block cell cycle and promote cell apoptosis. At the same time, HEATR3 knockdowns reduced the expression levels of p-AKT and p-ERK proteins. HEATR3 knockdown inhibits the development of BCa cells through the AKT/ERK signaling pathway. and it may become one of the most promising molecular targets for BCa treatment.