TLR4 and neoplasm: The scenario we propose on the mechanism of action of proTα and proTα(100–109) is that initially the peptides ligate TLR4 on the surface of TLR4-expressing APCs, e.g., DCs, inducing their maturation; activated APCs efficiently uptake antigens (e.g., tumor-derived peptides), overexpress MHC class I and II, secrete proinflammatory cytokines and chemokines, and elicit a potent Th1-polarized response.