PUF60 Promotes Chemoresistance Through Drug Efflux and Reducing Apoptosis in Gastric Cancer

<b>Background:</b> Chemotherapy resistance is a great challenge in the treatment of gastric cancer (GC), so it is urgent to explore the prognostic markers of chemoresistance. PUF60 (Poly (U)-binding splicing factor 60) is a nucleic acid-binding protein that has been shown to regulate transcription and link to tumorigenesis in various cancers. However, its biological role and function in chemotherapy resistance of GC is unclear. <b>Methods:</b> The expression and prognostic value of PUF60 in GC chemotherapy-resistant patients were analyzed by databases and K-M Plotter. The functional effect of PUF60 on chemoresistance in GC was studied by by RNA interference, CCK8 test, colony formation test and apoptosis detection. Moreover, further validation and mechanism exploration were conducted in clinical samples. <b>Results:</b> PUF60 was highly expressed in both GC and chemoresistant tissues, and was positively correlated with poor prognosis in GC patients treated with 5-fluorouracil (5-FU). In addition, the knockdown of PUF60 significantly reduced the proliferation of human gastric cancer cells and increased sensitivity to chemotherapy drugs, such as 5-FU and cisplatin (CDDP). Mechanistically, PUF60 enhances chemotherapy resistance in gastric cancer (GC) cells by actively excluding chemotherapy drugs via the recombinant ATP Binding Cassette Transporter A1 (ABCA1) and ATP Binding Cassette Subfamily C Member 1 (ABCC1). This process further affects the cell cycle, reduces cell apoptosis, and ultimately promotes resistance to chemotherapy in GC. <b>Conclusion:</b> PUF60 promotes chemoresistance in GC, resulting in poor prognosis of GC patients treated with 5-FU, and providing a new idea for overcoming the chemoresistance in GC.