However, conflicting evidence suggests that downregulation of TRPV4 in tumour endothelial cells leads to increased tumour angiogenesis and enhanced tumour growth in vivo [199], and that activation (rather than inhibition) of TRPV4 promotes cell death and inhibits in vivo tumour formation in certain breast cancer cell lines [188]. The gene discussed is TRPV4; the disease is breast carcinoma.