TRPC5 and cancer: Moreover, even if suitable small-molecule modulators of the channels can be identified, it needs to be recognised that TRPC4- and TRPC5-containing channels are just one mechanism by which a cancer cell might regulate the intracellular Ca2+ required for Ca2+-dependent cell processes; that is, it is quite conceivable that modulation of the channels could relatively easily be circumvented by an ever-adapting cancer cell.