TLR2 and obesity due to melanocortin 4 receptor deficiency: Notably, while TLR4-mediated signaling was demonstrated to promote liver fibrosis and fibrosis-associated tumorigenesis [53,57], TLR2 stimulation by LTA, in conjunction with the action of the secondary BA deoxycholate (DCA; a reported inducer of DNA damage [58] and apoptosis [59], was implicated in obesity-associated HCC [56].