CTLA4 and inflammatory bowel disease: Recently, a functional study found lower expression of the soluble (s)-CTLA4 isoform compared with the membrane-bound CTLA4 in lymphocytes from patients with inflammatory bowel disease with the CTLA-4 rs3087243 GG genotype compared with that of the AA genotype.[22] These results indicated that the CTLA-4 rs3087243 G→A variant might increase the expression of CTLA4, thereby elevating the T-cell activation threshold, leading to a weakened antitumor response and conferring a risk of HCC.