Platelet supernatant with longer storage inhibits tumor cell growth.

ABSTRACT

BACKGROUND: Platelet transfusion is an essential supportive treatment for cancer patients. Platelets promote metastasis, but their role in tumor growth remains controversial. This study aimed to explore the impact of apheresis platelet supernatants of different storage periods on tumor cell growth, optimize blood transfusion timing, and provide a reference for reducing the risks of platelet transfusion in cancer patients. METHODS: Eight human tumor cell lines, including HepG2, HuH7, SMMC-7721, HeLa, HCT116, MCF-7, K562, and Jurkat were cultured. After culturing the platelet supernatant of days 0, 3, 5, and 7 with tumor cells, counting kit 8 (CCK-8), scratch assay, and propidium iodide (PI) were used to evaluate cell proliferation, migration, and cell cycle, respectively. Metabolomics analysis was performed to confirm whether differential metabolites produced during platelet storage are involved in the cancer pathway. RESULTS: Platelet supernatants inhibit tumor cell proliferation by blocking the cell cycle at the G0/G1 phase, and their inhibitory effect increases with storage time. However, platelets promote tumor cells to form cytoskeletal connections, thereby promoting migration. Besides, metabonomics analysis of platelet supernatants during different storage periods reveals that upregulated differential metabolites are involved in cancer-related pathways. CONCLUSION: The role of platelets in tumor cells is two-sided, that is, they inhibit proliferation while promoting migration. Therefore, additional in-depth studies on the appropriate timing of platelet transfusion are necessary.