EGFR and Cushing syndrome: Further analysis of pathway enrichment among the upregulated genes in the paired and unpaired samples demonstrated enrichment in both paired and unpaired samples among their overlapped signaling pathways, including drug metabolism, MAPK, ErbB, calcium, cGMP-PKG, sphingolipid, PI3K-Akt, Cushing’s syndrome, HPV infection, and proteoglycans in cancers (p < 0.05) (Table 4).