S1PR1 and breast cancer: The answer is, unfortunately, no. Liu et al. [74] showed that S1PR1 can accelerate VE-cadherin phosphorylation (Y731) by activating RhoA, leading to increased endothelium-dependent vessel and reduced vasculogenic mimicry in breast cancer, and the low expression of S1PR1 is in line with the vasculogenic mimicry and poor prognosis in breast cancer patients.