Irradiation reduces bleomycin sensitivity in cervical squamous cancer cells in vitro.

ABSTRACT

PURPOSE OF INVESTIGATION The study was performed to examine how bleomycin (BLM) and peplomycin (PEM) should be effectively used in radiotherapy for cervical squamous cancer patients. METHODS: The effects of BLM on radiosensitivity and the effects of radiation on the sensitivity to BLM of cancer cells were investigated using the radiosensitive human cervical squamous cell carcinoma cell line ME180. RESULTS: BLM treatment did not affect radiosensitivity. However, irradiation significantly reduced cell BLM sensitivity in a dose-dependent manner. There was no significant difference in BLM sensitivity and PEM sensitivity between cells concurrently irradiated and those treated with BLM or PEM 8 h before or 8 h after irradiation. CONCLUSION: Since sensitivity to BLM is reduced during irradiation, BLM should be administered to cervical cancer patients as an adjuvant chemotherapeutic drug after completion of radiotherapy.