A positive feedback loop between TAZ and miR-942-3p modulates proliferation, migration, epithelial-mesenchymal transition process and glycometabolism in human bladder cancer

Abstract Background: Transcriptional co-activator with PDZ-binding motif (TAZ) has been reported to involve in tumor progression, epithelial-mesenchymal transition (EMT) process and glycometabolism modulation. Herein, the underlying molecular mechanisms of TAZ-induced biological effects in bladder cancer were discovered; Methods: qRT-PCR, western blot and immunohistochemistry were performed to determine the level of TAZ in bladder cancer cells and tissues; CCK-8 assay, Colony formation assay, wound healing assay and Transwell assay were performed to evaluate the functions of TAZ, miR-942-3p and GAS1. qRT-PCR and western blot were used to determine the expression levels of related genes. Chromatin immunoprecipitation and dual-luciferase reporter assay confirmed the interaction between TAZ and miR-942. In vivo tumorigenesis assay and colorimetric assay of glycolysis were also conducted; Results: We determined the upregulation and vital roles of TAZ in bladder cancer. TAZ-induced upregulation of miR-942-3p amplified upstream signaling by inhibiting the expression of large tumor suppressor 2 (LATS2, a TAZ inhibitor). MiR-942-3p attenuated the suppression of cell proliferation, EMT process and glycolysis induced by TAZ knockdown. Further, miR-942-3p resulted in restrained expression of growth arrest-specific 1 (GAS1) to modulate biological functions; Conclusion: Our study identified a novel positive feedback loop between TAZ and miR-942-3p that regulates biological functions in bladder cancer cells via GAS1 expression, and illustrated that TAZ and miR-942-3p might be potential therapeutic targets for bladder cancer treatment.