Additionally, the fourth small-molecule inhibitor, cucurbitacin B, is considered to specifically recognize the Cys253 site in the KH1-2 domain of IGF2BP1, which allosterically impairs the ability of IGF2BP1 to read m6A signals in RNAs, promoting apoptosis and activating immune responses in HCC 73. Here, IGF2BP1 is linked to hepatocellular carcinoma.