Combination of Cefotaxime and Cisplatin Specifically and Selectively Enhances Anticancer Efficacy in Nasopharyngeal Carcinoma.

BACKGROUND: HMOX1 has a dual role in cancers, especially involving chemoresistance. We demonstrate that cephalosporin antibiotics exert strong anticancer activity in nasopharyngeal carcinoma mainly via drastic upregulation of HMOX1. OBJECTIVES: Cephalosporin antibiotics are commonly used for the treatment or prophylaxis of bacterial infectious diseases in cancer patients. It is unknown whether they lead to chemoresistance in cancer patients, especially in nasopharyngeal carcinoma patients, who are being treated or required prophylaxis for an infectious syndrome with cephalosporin antibiotics. METHODS: MTT and clonogenic colony formation assays assessed the viability and proliferation of cultured cancer cells. Flow cytometry was used to detect apoptosis. Tumor growth was assessed using a xenograft model. Microarray and RT-qPCR expression analyses investigated differential gene expression. RESULTS: Cefotaxime enhanced anticancer efficacy of cisplatin in nasopharyngeal carcinoma without enhancing the toxic side effects both in vitro and in vivo. However, cefotaxime significantly reduced the cytotoxicity of cisplatin in other cancer cell lines. Cefotaxime and cisplatin co-regulated 5 differential genes in CNE2 cells in a direction supporting the enhancement of anticancer efficacy, of which, THBS1 and LAPTM5 were further upregulated, STAG1, NCOA5, and PPP3CB were further downregulated. Out of the 18 apoptotic pathways significantly enriched in the combination group, THBS1 and HMOX1 overlapped in 14 and 12 pathways, respectively. Extrinsic apoptotic signaling pathway (GO: 2001236) was the only apoptotic pathway commonly enriched in cefotaxime group, cisplatin group and combination group, and THBS1 and HMOX1 were the overlapped genes of this pathway. THBS1 also overlapped in P53 signaling pathway and ECM-receptor interaction signaling pathway enriched by KEGG. CONCLUSION: Cephalosporin antibiotics are chemosensitizers of conventional chemotherapeutic drugs in the chemotherapy of nasopharyngeal carcinoma, but they may lead to chemoresistance by cytoprotection in other cancers. Cefotaxime and cisplatin co-regulate THBS1, LAPTM5, STAG1, NCOA5 and PPP3CB suggesting their involvement in the enhancement of anticancer efficacy in nasopharyngeal carcinoma. Targeting of P53 signaling pathway and ECM-receptor interaction signaling pathway was correlated to the enhancement. With additional benefit for treatment or prophylaxis of an infectious syndrome, cephalosporin antibiotics can benefit the therapy of nasopharyngeal carcinoma either as anticancer agents or as chemosensitizers of chemotherapeutic drugs in combination chemotherapy.

Cephalosporin antibiotics specifically and selectively target nasopharyngeal carcinoma through HMOX1-induced ferroptosis.

AIMS: Many antibiotics derived from mold metabolites have been found to possess anticarcinogenic properties. We aimed to investigate whether they may elicit anticancer activity, especially against nasopharyngeal carcinoma. MAIN METHODS: The response of nasopharyngeal and other carcinoma cell lines to cephalosporin antibiotics was evaluated in vitro and in vivo. MTT and clonogenic colony formation assays assessed the viability and proliferation of cultured cells. Flow cytometry was used to assess cell cycle parameters and apoptotic markers. Tumor growth was determined using a xenograft model in vivo. Microarray and RT-qPCR expression analyses investigate differential gene expression. Mechanistic assessment of HMOX1 in cefotaxime-mediated ferroptosis was tested with Protoporphyrin IX zinc. KEY FINDINGS: Cephalosporin antibiotics showed highly specific and selective anticancer activity on nasopharyngeal carcinoma CNE2 cells both in vitro and vivo with minimal toxicity. Cefotaxime sodium significantly regulated 11 anticancer relevant genes in CNE2 cells in a concentration-dependent manner. Pathway analyses indicate apoptotic and the ErbB-MAPK-p53 signaling pathways are significantly enriched. HMOX1 represents the top one ranked upregulated gene by COS and overlaps with 16 of 42 enriched apoptotic signaling pathways. Inhibition of HMOX1 significantly reduced the anticancer efficacy of cefotaxime in CNE2 cells. SIGNIFICANCE: Our discovery is the first to highlight the off-label potential of cephalosporin antibiotics as a specific and selective anticancer drug for nasopharyngeal carcinoma. We mechanistically show that induction of ferroptosis through HMOX1 induction mediates cefotaxime anticancer activity. Our findings provide an alternative treatment for nasopharyngeal carcinoma by showing that existing cephalosporin antibiotics are specific and selective anticancer drugs.