Yildiz F, Perez R, Redpath J L
Department of Radiation Oncology, University of California Irvine, CA 92697, Irvine, USA.
Eur J Cancer. 2000 Jul;36(11):1426-32. doi: 10.1016/s0959-8049(00)00115-5.
The purpose of the present study was to investigate further the mechanisms underlying subadditive and superadditive interactions of radiation and paclitaxel treatments in vitro. The protocol studied was a fixed radiation treatment (7 Gy) followed either immediately or after a 10 h delay by paclitaxel treatment. Paclitaxel treatment was exposure to either a fixed dose of paclitaxel (10 nM) for varying time intervals up to 25 h, or varying doses of paclitaxel up to 20 nM for a fixed exposure time of 24 h. The cells used were HeLa. Cell survival was assessed by colony forming ability and apoptosis was measured by flow cytometry. The results show that when the paclitaxel exposure time was 24 h superadditive interactions were observed at all paclitaxel doses. A reasonable correlation between surviving fraction as measured by colony forming ability and apoptosis in the attached cells at the end of paclitaxel treatment was observed. The nature of the interaction of radiation and subsequent paclitaxel treatment is critically dependent on the duration of the paclitaxel treatment.
本研究的目的是进一步探究体外辐射与紫杉醇治疗产生亚相加和超相加相互作用的潜在机制。所研究的方案为固定剂量的辐射治疗（7 Gy），随后立即或延迟10小时后进行紫杉醇治疗。紫杉醇治疗包括在长达25小时的不同时间间隔内暴露于固定剂量的紫杉醇（10 nM），或在固定暴露时间24小时内暴露于高达20 nM的不同剂量的紫杉醇。所用细胞为HeLa细胞。通过集落形成能力评估细胞存活率，通过流式细胞术测量细胞凋亡。结果表明，当紫杉醇暴露时间为24小时时，在所有紫杉醇剂量下均观察到超相加相互作用。在紫杉醇治疗结束时，观察到通过集落形成能力测量的存活分数与贴壁细胞中的细胞凋亡之间存在合理的相关性。辐射与后续紫杉醇治疗相互作用的性质严重依赖于紫杉醇治疗的持续时间。
