Analysis of multiple cancers revealed that compared to adjacent normal tissues, the mRNA expression of CNKSR2 was significantly lower in cancers—such as ovarian serous cystadenocarcinoma (OV), pancreatic cancer (PAAD), pheochromocytoma and paraganglioma (PCPG), prostate cancer (PRAD), rectal cancer (READ), skin melanoma (SKCM), gastric cancer (STAD), testicular cancer (TGCT), thyroid cancer (THCA), thymic cancer (THYM) and endometrial carcinoma (UCEC) (Figure 1A). The gene discussed is CNKSR2; the disease is pheochromocytoma.