RETRACTED: Effects of Cisplatin Combined with Metformin on Proliferation and Apoptosis of Nasopharyngeal Carcinoma Cells (Retracted Article)

Background. Nasopharyngeal carcinoma (NPC) is an invasive squamous cell carcinoma located in the nasopharynx. NPC has a high recurrence risk after initial treatment due to its high metastatic and immune escape potential. One study has found that metformin can improve cancer outcomes and reduce cancer incidence. Objective. With antitumor activity, metformin can have low toxicity when used in combination with some common chemotherapy drugs. This study was designed to explore the effects of cisplatin combined with metformin on the proliferation and apoptosis of nasopharyngeal carcinoma (NPC) cells. Methods. An appropriate cisplatin concentration was selected for NPC cells, and the cells were treated with metformin at a gradient concentration, and then, some of them were treated with cisplatin. Subsequently, the biological effects (activity, migration, invasion, and apoptosis) of metformin alone and metformin combined with cisplatin on NPC cells were evaluated. Results. Metformin alone inhibited cell activity, migration, and invasion and promoted cell apoptosis in a concentration-dependent and time-dependent manner, while compared with cisplatin alone, cisplatin combined with metformin had stronger inhibition on cell activity, migration, and invasion and stronger induction to cell apoptosis, and a higher concentration of them demonstrated stronger effects. Conclusion. Cisplatin combined with metformin can strongly inhibit the activity of NPC cells and promote their apoptosis.