Tumor cells also release adenosine triphosphate (ATP) [13], high mobility group box 1 protein (HMGB1) [13,14], and calreticulin [13,15], which are recognized by cell surface receptors P2X7, CD91, and toll-like receptor 4 (TLR4), respectively, on DCs. This evidence concerns the gene TLR4 and neoplasm.