SSH1 and paraganglioma: Our analysis of the expression of SSH1 mRNA levels in tumor and non-tumor samples from patients with one of 23 cancer types contained in The Cancer Genome Atlas (TCGA) database showed that compared to the non-tumor samples, SSH1 was significantly upregulated in cholangiocarcinoma (CHOL) (p < 0.001), head and neck squamous cell carcinoma (HNSC) (p < 0.01), pheochromocytoma and paraganglioma (PCPG) (p < 0.01), thyroid cancer (THCA) (p < 0.01), and in liver hepatocellular carcinoma (LIHC, n = 421) (p < 0.01) (Figure 1A).