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

为了提高放射治疗的疗效，必须解决分治过程中肿瘤复发导致放射耐药的原因。通过1997-1998这两个财政年度，我们获得了以下关于小鼠空肠隐窝分娩期增殖反应的实验数据。通过实验，分数（fx）的大小为2 Gy。1)在分离过程中，隐窝内的克隆细胞迅速增殖，增殖的程度取决于分数的大小，每天2次处理诱导大于每天1次处理。2)与每天1次处理相比，每天2次处理时，隐窝细胞数量显著增加。3)两种处理均能加快分蘖过程中潜在翻倍时间（Tpot），但对Tpot没有影响。4)每天2英尺处理比每天1英尺处理从隐窝到绒毛的过渡时间慢；即降低细胞损失因子。5)细胞凋亡数量在2fix -a组明显高于1fix -a组。为了总结这些结果，观察了小鼠空肠隐窝在分娩期的再繁殖情况，并与每天的分娩期数有关。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细胞的数量。Tpot的缩短和细胞损失因子的降低是分选过程中再生的原因。这些论文正准备出版。关于再繁殖的临床数据也报告了与总体治疗时间、加速分离和DNA倍性等相关的数据。另一项临床数据表明，在分娩期化疗的时机很重要，这也导致了良好的结果。

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.