This relationship between P2Y2R and P2X4R gene expression remarks the potential of purinergic signaling as a prospective biomarker for gastric cancer progression, as similar studies have reported for P2X7R, whose overexpression is related to tumor size, metastatic potential, and overall survival in human colorectal and gastric cancer [41,42]. The gene discussed is P2RX4; the disease is gastric cancer.