Xu Y H, Campbell H A, Sattler G L, Hendrich S, Maronpot R, Sato K, Pitot H C
McArdle Laboratory for Cancer Research, Medical School, University of Wisconsin, Madison 53706.
Cancer Res. 1990 Feb 1;50(3):472-9.
Altered hepatic foci (AHF) were analyzed by quantitative stereology on frozen serial sections stained sequentially for gamma-glutamyltranspeptidase (GGT), canalicular adenosine triphosphate (ATPase), glucose-6-phosphatase (G6Pase), and the placental isoenzyme of glutathione S-transferase (GST). Livers for these analyses were obtained from both male and female rats of different ages which had been subjected to initiation with a nonnecrogenic dose of diethylnitrosamine following a 70% partial hepatectomy with subsequent phenobarbital (PB) feeding. Different combinations of these four marker alterations (from single marker to four-marker combinations) were used to analyze the data, and the results were compared for their ability to detect AHF. In rats on the above protocol, GST was the single most effective marker, exhibiting a high sensitivity for scoring both number and volume of foci. There was a high degree of overlap with GGT. The combination of the four different markers, GST/GGT/ATPase/G6Pase, scored 80% more foci in number and 60% more in volume than the routinely used GGT/ATPase/G6Pase method. When all four markers were used to score AHF, PB promotion was equally effective in both sexes at weaning and at 6 months of age, but at 1 year of age males showed a dramatic reduction in the effectiveness of PB as a promoting agent, both for number and volume percentage of liver occupied by AHF. On the other hand, initiation was more effective in the male at weaning and at 6 months of age, although by the 12-month point no distinction between the sexes could be made. When only GGT was used as a marker, promotion by PB appeared to be markedly less effective in males than in females at all ages. In the absence of PB administration, both the number and volume fraction of AHF in the livers of both males and female increased with age. Likewise, both the number of AHF per liver and their volume fractions increased with age in both sexes when uninitiated animals were fed PB, although only after a 6-month lag in females. These experiments demonstrate that the stages of initiation and promotion in hepatocarcinogenesis in the rat as monitored by the number and volume percentage occupied of AHF are altered by both the age and the sex of the animal. The combination of GGT and GST identified all AHF scored by the GST/GGT/ATPase/G6Pase set of markers and thus may be the most efficient combination of markers of AHF resulting from promotion by PB.
对经γ-谷氨酰转肽酶（GGT）、胆小管三磷酸腺苷酶（ATPase）、葡萄糖-6-磷酸酶（G6Pase）以及谷胱甘肽S-转移酶胎盘同工酶（GST）顺序染色的冰冻连续切片，采用定量体视学方法分析肝病灶（AHF）。用于这些分析的肝脏取自不同年龄的雄性和雌性大鼠，这些大鼠在70%部分肝切除术后，接受非致坏死剂量的二乙基亚硝胺启动处理，随后喂食苯巴比妥（PB）。使用这四种标志物改变的不同组合（从单一标志物到四种标志物组合）分析数据，并比较结果检测AHF的能力。在上述实验方案的大鼠中，GST是最有效的单一标志物，对病灶数量和体积评分均表现出高敏感性。与GGT有高度重叠。四种不同标志物GST/GGT/ATPase/G6Pase的组合，在病灶数量上比常规使用的GGT/ATPase/G6Pase方法多评分80%，在体积上多评分60%。当使用所有四种标志物对AHF评分时，PB促进在断奶时和6月龄时对两性同样有效，但在1岁时，对于AHF占据肝脏的数量和体积百分比，雄性大鼠中PB作为促进剂的有效性显著降低。另一方面，启动在断奶时和6月龄时对雄性更有效，尽管到12个月时无法区分两性。当仅使用GGT作为标志物时，在所有年龄，PB对雄性的促进作用似乎明显低于雌性。在不给予PB的情况下，雄性和雌性大鼠肝脏中AHF的数量和体积分数均随年龄增加。同样，未启动处理的动物喂食PB时，两性肝脏中AHF的数量及其体积分数也随年龄增加，不过雌性有6个月的滞后。这些实验表明，大鼠肝癌发生中由AHF占据的数量和体积百分比监测的启动和促进阶段，受动物年龄和性别的影响。GGT和GST的组合识别出了由GST/GGT/ATPase/G6Pase标志物组评分的所有AHF，因此可能是PB促进导致的AHF最有效的标志物组合。
