【摘要】 <正> 肝癌的癌变机理是肿瘤基础理论研究中的一个重要课题。目前发现肝癌的化学致癌剂种类虽多,但它们对肝组织均具有类似的作用,其毒性作用可引起成熟肝细胞的变性和坏死,其刺激作用可引起肝组织中潜在的干细胞(一种原始的未分化细胞——卵圆细胞)的增生,这种增生的干细胞可分化为成熟的肝细胞,在一定条件下(如致癌剂的长期持续作用),由于分化发生障碍而逐步演变为癌更多还原

【Abstract】 A systemic study on the dynamie changes of early and precancerous stages during3-Me-DAB hepatocarcinogenesis of rats was made, using histochemistry, immunofluoresence and electronicmicroscopy. During early stages of carcinogenesis, oval cell proliferation was found to be moststriking. Oval cells were considered to be probably undifferentiated stem cells of the livercapable of further differentiation. Some of them could transform into transitional cellswith potentiality to differentiate into small hepatocyte showing positive AFP in their cyto-plasm. Further differentiation into mature hepatocyte as well as cholangiolar cells could beobserved. Transtions from oval cells to small hepatocytes and to precancerous lesions (hyper-plastic area, hyperplastic nodules etc) were found. Hepatocytes in the precancerous lesionswere characterized by depletion of functional enzymes of mature hepatocytes, such asG--6--Pase, ATPase and presenec of enzymes of embryonic hepatocytes such as γ--GTase.These evidences showed that cells of precancerous lesions were immature hepatocytes. The relationship between cell differentiation and cancerous changes were discussed.The possible pathological basis and mechanism of persistent low titer of serum AFP incertain patients were also discussed in this paper.更多还原