HAMP and small cell lung carcinoma: The KEGG pathway analysis revealed two pathways that were positively correlated with high expression levels of HAMP, namely the oxidative phosphorylation and T cell receptor signaling pathways, and six negatively related pathways: autoimmune thyroid disease, the B cell receptor signaling pathway, Huntington’s disease, the JAK-STAT signaling pathway, non-small cell lung cancer, pancreatic cancer and small cell lung cancer (Figure 6C).