When we performed a ratio between the relative expression of these two receptors, a 3:1 to 6:1 P2Y2R/P2X4R ratio is observed in these GC-derived cell lines, with certain differences that could be attributed to the stage and grade of gastric cancer that these cell lines represent: AGS correspond to human primary adenocarcinoma cells, and MKN-74 and MKN-45 are human metastatic adenocarcinoma cells with a moderate and poor differentiation rate, respectively [40]. The gene discussed is P2RX4; the disease is gastric cancer.