MicroRNA-363 inhibits angiogenesis, proliferation, invasion, and migration of renal cell carcinoma via inactivation of the Janus tyrosine kinases 2-signal transducers and activators of transcription 3 axis by suppressing growth hormone receptor gene

Abstract

Renal cell carcinoma (RCC) is the most common malignancy involving the kidneys and a major cause of cancer mortality. The involvement of microRNA (miRNA) expression in the tumorigenesis and progression of RCC has been previously highlighted. Therefore, we conducted this study to investigate whether microRNA-363 (miR-363) affects the development of RCC via the Janus tyrosine kinases (JAK2)-signal transducers and activators of transcription (STAT) axis by targeting the growth hormone receptor (GHR), by observing the changes that occurred in the RCC and the normal adjacent tissues of patients with RCC. RCC cells were transfected with a series of miR-363 mimic, miR-363 inhibitor, or small interfering RNA against GHR to determine the influence of miR-363 on the expression of GHR and JAK2-STAT3 axis-related genes with the use of reverse transcription quantitative polymerase chain reaction and Western blot analysis. The angiogenesis, viability, invasion, and migration of cells were evaluated by means of in vitro angiogenesis, 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide (MTT), wound-healing, and Transwell assays. The results revealed reduced miR-363 expression and elevated GHR expression in RCC. It was also found that miR-363 altered the activation of the JAK2-STAT3 axis through the inhibition of GHR. Cells treated with the miR-363 inhibitor presented with increased capillary vessels, cell viability, invasion, and migration, whereas it was on the contrary in the RCC cells with overexpressed miR-363. These results implicated that the overexpression of miR-363 could specifically bind to GHR to downregulate the expression of GHR, which, in turn, inactivates the JAK2-STAT3 axis, thereby influencing the angiogenesis, cell invasion, and migration abilities in RCC.

Keywords: Janus tyrosine kinases-signal transducers and activators of transcription (JAK2-STAT3) axis; angiogenesis; growth hormone receptor (GHR); invasion; microRNA-363 (miR-363); migration; renal cell carcinoma (RCC).