This latter study also used immunolabeling of IP3Rs and NCX to show that both proteins were highly expressed in ICC, suggesting that they formed a microdomain and that influx via reverse‐mode NCX regulated ICC Ca2+ signaling via modulation of IP3Rs. Under our experimental conditions, ENCX has been calculated at −72 mV and membrane potentials positive to this value would result in the exchanger switching to reverse mode and allowing Ca2+ influx rather than extrusion. This evidence concerns the gene TLX2 and intrahepatic cholangiocarcinoma.