HIF1A and nonpapillary renal cell carcinoma: For example, HIF1A upregulates the negative immune checkpoint regulator V-set immunoregulatory receptor (VSIR) in colon cancer [27] and increases interleukin (IL)-23 expression in glutamine-deficient macrophages, which may suppress T cell immune function in clear cell renal cell carcinoma (ccRCC) to achieve immune escape [28].