Cstf2, also known as cleavage-stimulating factor subunit 2 or CSTF-64, is an RNA-binding protein. It is an essential component of the cleavage stimulating factor (CSTF), located on the X chromosome and encoding 557 amino acids. Cstf2 is crucial for the cleavage and polyadenylation of mRNA, a process that impacts pre-mRNA 3'-end processing, which in turn is related to gene expression regulation and various biological pathways [2].

In hepatocellular carcinoma (HCC), Cstf2 knockout inhibits the proliferation, migration, invasion of HCC cells in vitro and tumor formation in vivo. It is associated with enhanced glycolysis, as knocking out Cstf2 reduces the level of the short 3' UTR isoform of hexokinase 2 [3].

In pancreatic ductal adenocarcinoma (PDAC), Cstf2 co-transcriptionally regulates m6A installation, distinguishing two PDAC subtypes with different prognosis outcomes. Most of the Cstf2-regulated m6As positively affect the RNA level of host genes [1].

In glioblastoma, knockdown of Cstf2 induces cell apoptosis both in vitro and in vivo by unstabilizing the mRNA of the BAD protein through shortening its 3' UTR [4].

In conclusion, Cstf2 is vital for mRNA processing and has significant implications in cancer-related biological processes. Gene knockout studies in mouse models for Cstf2 have revealed its roles in promoting cancer progression in HCC, PDAC, and glioblastoma, suggesting it could be a potential biomarker and therapeutic target for these cancers.