The calcium signaling pathway (hsa04020) contained 23 genes (p = 8.81 × 10−7), including key receptors such as SLC8A2, HTR2C, GRIN1, CACNA1I, and GRIN2B, which regulate intracellular calcium levels and tumor microenvironment dynamics via glutamate interactions. The gene discussed is CACNA1I; the disease is neoplasm.