B-cell lymphoma-extra large (Bcl-xl) is an anti-apoptotic member of the B-cell lymphoma 2 (Bcl-2) family that is often found to be overexpressed in human hepatocellular carcinoma (HCC), therefore conferring a survival advantage to tumor cells. microRNA (miRNA) let-7b is downregulated in HCC and its expression correlates with multidrug resistance. Using computational programs, it was predicted that the 3' untranslated region (UTR) of the Bcl-xl gene contains a potential miRNA binding site for let-7b, and that a single nucleotide polymorphism (SNP) site rs3208684 (A or C allele) resides within t...