DIRAS1 and renal cell carcinoma: Functionally, several studies showed that DIRAS-1 acts as a potential tumor suppressor by inhibiting cell proliferation and cell viability in different types of cancer, such as renal cell carcinoma, colorectal cancer, murine ovarian cancer cells, and esophageal squamous cell carcinoma, as well as gliomas [2,4,5,6] and that DIRAS-1 can also suppress tumor growth in nude mice [7].