Neuropilin-1 contributes to esophageal squamous cancer progression via promoting P65-dependent cell proliferation
Neuropilin-1 (NRP1) is a non-kinase receptor recently implicated in tumor progression. Here we revealed that over-expression of NRP1 correlates with poor prognosis in esophageal squamous cell carcinoma (ESCC). NRP1-knockdown suppressed ESCC cell proliferation and xenograft tumor growth. Reduced NRP1 expression downregulated P65 mRNA and protein expression, and ectopic expression of P65-restored cell proliferation in NRP1-silenced cells. NRP1 regulates P65 transcription by activating cAMP responsive element binding protein (CREB). NRP1 interacted with and activated epidermal growth factor receptor (EGFR), and b1/b2 domain of NRP1 is responsible for the activation of EGFR. We also found that EGFR regulated CREB transcriptional activity via AKT. These data suggest that NRP1 is an upstream regulator in the P65-dependent proliferation signaling pathway and a candidate therapeutic target for ESCC.