Here, we report that MALAT1 can stabilize interaction between the SFs polypyrimidine tract–binding protein 1 (PTBP1, also known as hnRNP I) and PTB-associated SF (PSF), thereby forming a functional module that operates in the regulation of pre-mRNA AS, and show that the functional module might be implicated in the pathogenesis of hepatocellular carcinoma (HCC). The gene discussed is MALAT1; the disease is hepatocellular carcinoma.