SRSF1-IN-1 (STP2) is an inhibitor of SRSF1 that modulates the splicing of Bcl-x precursor mRNA by downregulating SRSF1 expression. It exhibits antitumor activity in vitro and in vivo, with IC50 values ranging from 0.33 to 6.93 μM against cancer cells such as HepG2 and MCF7. In mice, SRSF1-IN-1 demonstrates a high safety profile, as intraperitoneal administration of 1 g/kg does not lead to mortality or pathological damage. SRSF1-IN-1 holds potential for research in the field of antitumor therapy [1].