In the RCC cell line Caki‐2, GABA stimulation promotes cancer cell invasion via ERK1/2‐dependent upregulation of MMPs; an effect mediated mainly through the GABA‐B receptor.19 Thus, while DNA methylation changes may serve as prognostic markers in pRCC, they may also functionally influence the underlying biology of the disease. This evidence concerns the gene MAPK3 and cancer.