CMTM6 promotes cell proliferation and invasion in oral squamous cell carcinoma by interacting with NRP1

Previous studies have identified that both CKLF-like MARVEL transmembrane domain-containing member (CMTM6) and Neuropilin-1 (NRP1) played an essential part in regulating tumorigenesis and immune response. However, the potential connection between CMTM6 and NRP1 in oral squamous cell carcinoma (OSCC) remains unknown. In this study, we investigated the clinicopathologic significance of CMTM6 and NRP1 in OSCC. We examined the co-expression of CMTM6 and NRP1 in both OSCC tissues and cell lines. Co-overexpression of CMTM6 and NRP1 was generally highly expressed in cancer tissues and is associated with poor prognosis. Gain- and loss-of-function assays confirmed the oncogenic properties of CMTM6 in OSCC cells. Depletion of NRP1 abrogated tumorigenesis induced by CMTM6. By performing co-immunoprecipitation (co-IP), we discovered a potential interaction between CMTM6 and NRP1. Meanwhile, the stability of CMTM6 was significantly decreased in the NRP1-silencing cells, indicating the involvement of NRP1 in the degradation process of CMTM6. The crosstalk between CMTM6 and NRP1 provided a new insight into the progression of OSCC, which may indicate an alternative strategy for OSCC treatment.