IDO1 and neoplasm: Studies on tumor biopsies, assessed markers involved in immune regulation (CD4, CD8, CXCL2, CXCR4, FOXP3, IFN-γ, IL-6, IL-8, IL-17, PD-1, TLR-4, TLR-9), cell signaling (AHR, AKT1, c-Jun, FOXO1, PDCD4, SMYD3, STAT3), inflammatory and antimicrobial processes (CD68, DC-SIGN, DEFA4, H3cit, hBD-1, hBD-2, hBD-3, HNP-1/3, LDH, MPO), cell proliferation and apoptosis (BIM, CD44, Ki-67, P53), invasion and angiogenesis (IDO1, LTSCCAT, miR-21, SDF1, TDO2).