Low-dose metronomic chemotherapy with cisplatin enhanced immunity in a murine model of ectopic cervical cancer

Summary Previous researchers have claimed that metronomic low‐dose/dense chemotherapy can enhance the therapeutic effectiveness of cisplatin treatment in the control of cancer. Therefore, the aim of this study was to explore the effectiveness of metronomic drug delivery with regards to its effects on adaptive immunity in a murine model of ectopic cervical cancer. The effectiveness of long‐term low‐dose/dense cisplatin treatment in HPV E7‐expressing TC‐1 cells was evaluated via morphological observations. Tumour mass and survival curves were used to determine the antitumour effect against E7‐expressing tumours. After experimental mice had been treated with low‐dose/dense cisplatin therapy, flow cytometry was used to measure the expression of MHC class I surface antigens on cultured TC‐1 cells. Splenocytes expressing both interferon (IFN)‐γ and CD8 responsible for E7 antigens and the Treg population were also quantified using flow cytometry. The results indicate that in vivo treatment with metronomic cisplatin suppresses the growth of cultured TC‐1 cells. An increase was also observed in the number of splenocytes expressing both IFN‐γ and CD8 responsible for E7 antigens and the Treg population. These results support previous reports that metronomic low‐dose/dense cisplatin chemotherapy is an effective treatment against ectopic cervical cancer with E7‐expression.