PTH and cancer: In the KEGG pathway analysis, the DEGs participated in diverse hormonal signaling pathways, including parathyroid hormone’s synthesis, secretion, and action, cortisol synthesis and secretion, aldosterone synthesis and secretion, and some cancer-associated pathways such as the PI3K-Akt (Phosphatidylinositide 3-kinases-protein kinase B) signaling pathway, focal adhesion pathway, and several others that are involved in small cell lung carcinomas (Figure 2d).