P4HA2 and pheochromocytoma: Consistent with the expression trend in CC, P4HA2 expression was upregulated in BRCA (breast invasive carcinoma), CHOL (cholangiocarcinoma), ESCA (esophageal carcinoma), HNSC (head and neck cancer), KIRC (kidney renal clear cell carcinoma), LIHC (liver hepatocellular carcinoma), PCPG (pheochromocytoma and paraganglioma), STAD (stomach adenocarcinoma), and THCA (thyroid carcinoma).