Antibiotic-chemotherapy interaction in brain tumors: cefazolin reduces chemotherapeutic efficacy of irinotecan in glioblastoma and neuroblastoma cells.
Brain tumors are among the most aggressive and hard-to-treat cancers, characterized by poor prognosis and high resistance to conventional therapies. In this study, we explore the potential dual role of Cefamezin (cefazolin)-a widely used antibiotic in treating a broad range of infections in two high-grade cancer cell models: glioblastoma (LN-18) and neuroblastoma (SH-SY5Y). By investigating the impact of cefazolin on cancer cell viability and its interaction with chemotherapeutic agents, we aim to uncover how antibiotics, typically used to combat infections, might influence cancer treatment outcomes. In this study, the metabolic activity of SH-SY5Y and LN-18 cells under irinotecan, cefazolin, and combined treatment conditions was assessed using the MTT assay. In addition, cell cycle phase distribution and cell death-associated changes were evaluated by flow cytometry. Irinotecan induced significant cytotoxicity in both cell lines and increased the proportion of Sub G0/G1 cells while causing arrest in the S and G2/M phases. Co-treatment with cefazolin attenuated the inhibitory effects of irinotecan on cell viability and partially attenuated irinotecan-induced changes in cell cycle distribution. In SH-SY5Y cells, irinotecan-induced cytotoxicity and cell cycle disruption were reduced in the presence of cefazolin. In LN-18 cells, cefazolin partially attenuated the effects of irinotecan on cell viability, while necrosis rates were not significantly altered. These findings suggest that cefazolin may antagonize the cytotoxic effects of irinotecan in vitro. This study highlights the potential for antibiotic-chemotherapy interactions and underscores the need for further validation in in vivo and clinically relevant models.