Our findings that UC cell lines derived from high grade tumors displayed abundant Met protein but no detectable HGF are consistent with the four TCGA bladder cancer datasets which show frequent but mutually exclusive (odds ratio: <0.000001, strong tendency toward mutual exclusivity) overexpression of HGF or MET genes [13,14], and suggest that this pathway may be activated in a predominantly paracrine mode in bladder cancer. Here, HGF is linked to urinary bladder cancer.