COMPREHENSIVE ANALYSIS OF PROLIFERATIVE RESPONSES IN MURINE JEJUNAL CRYPT DURING MULTIPLE FRACTIONATION

为了提高放射治疗的疗效，必须解决分割过程中肿瘤再增殖导致放射抵抗的原因。通过1997-1998财政年度，我们获得了以下关于小鼠空肠隐窝分离期间增殖反应的实验数据。通过实验确定了fx剂量为2戈伊。1)克隆形成细胞在隐窝中迅速重新填充在分馏和重新填充的程度取决于馏分大小一天：2-fx-一天的治疗诱导超过1-fx-一天的治疗。2)与每天1次治疗相比，每天2次治疗期间隐窝中的细胞数量显著增加。3)两种治疗引起更快的潜在倍增时间（Tpot）在分馏，并没有改变Tpot。4)从隐窝到绒毛的过渡时间显示在每天2英尺的处理期间比每天1英尺的处理慢;即细胞损失因子降低。5)细胞凋亡的数量在2-fx-a-day治疗组比1-fx-a-day治疗组增加更多。总结这些结果，在小鼠空肠隐窝的分离过程中观察到细胞再增殖，并且依赖于每天的分离次数。这种增殖反应增加了隐窝中细胞的数量，从而维持了隐窝中克隆形成细胞的数量。Tpot缩短和细胞损失因子降低是分离过程中再增殖的原因。本文还报道了与总治疗时间、加速分离和DNA倍体有关的再增殖的临床数据。另一项临床数据表明，在分割化疗的重要性，导致了良好的结果也被报道。

To improve the efficacy of radiation therapy, the cause of radioresistance due to tumor repopulation during fractionation should be solved. Through these fiscal years of 1997-1998, we obtained the following experimental data regarding proliferative responses during fractionation in murine jejunal crypt. Through the experiments, fraction (fx) size was 2 Gy. 1) Clonogenic cells in the crypt were rapidly repopulating during fractionation and the extent of repopulation was dependent on fraction size a day : 2-fx-a-day treatment induced more than 1-fx-a-day treatment. 2) Number of cells in the crypt increased significantly during 2-ft-a-day treatment compared with 1-fx-a-day treatment. 3) Both treatments caused faster potential doubling time (Tpot) during fractionation and did not vary the Tpot. 4) Transition time from crypt to villi showed slower during 2-fx- a-day treatment than 1-ft-a-day treatment ; i.e. decreased cell loss factor. 5) Number of apoptosis was more increased during 2-fx-a-day treatment than 1-fx-a-day treatment.To summarize these results, repopulation during fractionation inmurine jejunal crypt was observed and was dependent on the fraction number a day. Such proliferative responses increased the number of cells in the crypt and, thus, maintained the number of clonogenic cells in the crypt. Shortening of Tpot and decreased cell loss factor is the causes of repopulation during fractionation. These papaers are in prepare for publications.Clinical data regarding repopulation were also reported inrelationship to such as overall treatment time, accelerated fractionation and DNA ploidy. Another clinical data suggesting importance in timing of chemotherapy during fractionations which caused an excellent results were also reported.