Radiation enhances cisplatin-sensitivity in human cervical squamous cancer cells in vitro.

ABSTRACT

UNLABELLED PURPOSE AND METHODS OF INVESTIGATION Cisplatin (CDDP) is regularly used in concurrent chemoradiotherapy in patients with advanced cervical cancer although an effective protocol of chemoradiotherapy with CDDP has not yet been established. In search of a better chemoradiotherapy protocol, we investigated both CDDP effects on radiosensitivity and irradiation effects on CDDP-sensitivity using the radiosensitive human cervical squamous cell carcinoma cell line ME180. RESULTS: We found that CDDP did not affect cellular radiosensitivity, and that irradiation significantly enhanced CDDP-sensitivity. Moreover, all the four post-irradiation surviving subclones obtained from repetitively irradiated ME180 cells showed significantly higher CDDP sensitivities than those of the non-irradiated parent cells. CONCLUSION: These results suggest that an effective protocol would involve the concurrent administration of CDDP with radiotherapy and further administration following completion of radiotherapy in order to achieve higher CDDP-sensitivities.