PAQR5 inhibits the growth and metastasis of clear cell renal cell carcinoma by suppressing the JAK/STAT3 signaling pathway.

BACKGROUND: Clear cell renal cell carcinoma (ccRCC) has a high degree of malignancy and poor overall prognosis in advanced and metastatic patients. Therefore, it is of great significance to find new prognostic biomarkers and therapeutic targets for ccRCC. The expression of progestin and adipoQ receptor family member 5 (PAQR5) is significantly downregulated in ccRCC compared with normal tissues, but its specific mechanism and potential biological function in ccRCC remain unclear. METHODS: The expression pattern of PAQR5 and the correlation between the PAQR5 expression and clinicopathological parameters and various survival periods in ccRCC patients were analyzed by using multiple public databases and ccRCC tissues chip. Its prognostic value was analyzed by univariate/multivariate Cox regression. In addition, MTT assay, EdU staining assay, flow cytometry, wound healing assay, transwell migration and invasion assay, colony formation assay, immunofluorescence assay, and a xenograft tumor model were conducted to assess the biological function of PAQR5 in ccRCC in vitro and in vivo. RESULTS: Our results indicated that the downregulation of PAQR5 was demonstrated in ccRCC tumor tissues and associated with poorer OS, DSS, and PFI. Meanwhile, the univariate/multivariate Cox regression analysis confirmed that PAQR5 might serve as an independent prognostic factor for ccRCC, and its low expression was tightly correlated with tumor progression and distant metastasis. Mechanistically, a series of gain- and loss-of-function assay revealed that PAQR5 could suppress the ccRCC proliferation, invasion, metastasis, and tumorigenicity in vitro and in vivo by inhibiting the JAK/STAT3 signaling pathway. CONCLUSION: Our study revealed the tumor suppressor role of PAQR5 in ccRCC. PAQR5 is a valuable prognostic biomarker for ccRCC and may provide new strategies for clinical targeted therapy.