DPP4 and hepatocellular carcinoma: Of note, DPP-4 and TLR-4 exhibit a crosstalk regulation, as sDPP-4 upregulates TLR-4; meanwhile, TLR-4 induces DPP-4 expression, creating a positive feedback loop that augments the pro-i nflammatory and pro-carcinogenic responses.40,54 Accordingly, the inhibition of DPP-4 has been shown to mitigate inflammation via downregulating TLR-4 signalling.55,56 Furthermore, alogliptin, a DPP-4 inhibitor, attenuated diethyl nitrosamine-i nduced hepatocellular carcinoma via TLR-4 downregulation.57