The results of GSEA showed that the GPR27 has a negative association with macrophages (R =  − 0.551, P < 0.001), neutrophils (R =  − 0.473, P < 0.001), aDC (R =  − 0.405, P < 0.001), eosinophils (R =  − 0.397, P < 0.001), iDC cells (R =  − 0.324, P < 0.001), cytotoxic cells (R =  − 0.286, P < 0.001), etc. These findings indicate that GPR27 may play a crucial role in modulating the immune response in the tumor microenvironment. This evidence concerns the gene GPR27 and neoplasm.