利用离体大白鼠肝癌细胞的EROD诱导指示二恶英的复合毒性效应

离体条件下 ,以大白鼠肝癌细胞株H4IIE的 7 乙氧基 3 异吩恶唑酮 脱乙基酶 (EROD)活力诱导作为毒性指标 ,测定了 2 ,3,7,8 TCDD单独存在以及与一定浓度的 2 ,3,7,8, TCDF ,OCDD ,PCB12 6和PCB77分别共存下的EROD活力 ,并用TEF和独立作用模型 (independence)两种方法对实验结果进行了评估。利用TEF评估的结果表明实验的TEQ值和理论计算的TEQ值十分接近 ,复合毒性表现为加合作用 (additivi ty) ,这一结果与用独立作用模型评估的结果完全一致。研究结果不仅证实了TEF评估方法的有效性和利用模型方法评估二恶英类化合物复合毒性的可行性 ,同时还表明离体条件下 ,大白鼠肝癌细胞株H4IIE的EROD酶活力诱导适用于化合物的复合毒性的研究。

大白鼠肝癌细胞系FSK7901,FSK 7902及其实体瘤的表皮角蛋白免疫细胞化学定位

我们制备了牛表皮角蛋白(EK)的家兔抗体,并表明这种抗体可被用来作为肝内胆管细胞性肝癌的特异性标志物,以与肝细胞肝癌鉴别。在实体瘤中,FSK 7901、FSK 7902细胞系的组织学结构分别与肝内胆管细胞性肝癌和肝细胞肝癌相同,免疫荧光和PAP染色都表明,FSK7901细胞EK阳性,而实体瘤中的绝大多数FSK7902细胞EK阴性。因而作者认为,FSK 7901、FSK 7902细胞系分别属于胆管细胞性肝癌和肝细胞肝癌。FSK7902细胞系的实体瘤中,极少数癌细胞呈EK阳性。作者推测,它们可能是含有或正在形成Mallory小体的细胞。

Increased expression of chondroitin sulphate proteoglycans in rat hepatocellular carcinoma tissues

AIM:To investigate the expression of chondroitin sulphate proteoglycans(CSPGs)in rat liver tissues of hepatocellular carcinoma(HCC).METHODS:Thirty male Sprague Dawley rats were randomly divided into two groups:control group(n=10) and HCC model group(n=20).Rats in the HCC model groups were intragastrically administrated with 0.2%(w/v)N-diethylnitrosamine(DEN)every 5 d for 16 wk,whereas 0.9%(w/v)normal saline was administered to rats in the control group.After 16 wk from the initiation of experiment,all rats were killed and livers were collected and fixed in 4%(w/v)paraformaldehyde.All tissues were embedded in paraffin and sectioned.Histological staining(hematoxylin and eosin and Toluidine blue)was performed to demonstrate the onset of HCC and the content of sulphated glycosaminoglycan(sGAG).Immunohistochemical staining was performed to investigate the expression of chondroitin sulphate(CS)/dermatan sulphate(DS)-GAG,heparan sulphate(HS)-GAG,keratan sulphate(KS)-GAG in liver tissues.Furthermore,expression and distribution of CSPG family members,including aggrecan,versican,biglycan and decorin in liver tissues,were also immunohistochemically determined.RESULTS:After 16 wk administration of DEN,malignant nodules were observed on the surface of livers from the HCC model group,and their hepatic lobule structures appeared largely disrupted under microscope.Toluidine blue staining demonstrated that there was an significant increase in sGAG content in HCC tissues when compared with that in the normal liver tissues from the control group[0.37±0.05 integrated optical density per stained area(IOD/area)and 0.21± 0.01 IOD/area,P<0.05].Immunohistochemical studies demonstrated that this increased sGAG in HCC tissues was induced by an elevated expression of CS/DS(0.28±0.02 IOD/area and 0.18±0.02 IOD/area,P< 0.05)and HS(0.30±0.03 IOD/area and 0.17±0.02 IOD/area,P<0.01)but not KS GAGs in HCC tissues.Further studies thereby were performed to investigate the expression and distribution of several CSPG components in HCC tissues,including aggrecan,versican,biglycan and decorin.Interestingly,there was a distinct distribution pattern for these CSPG components between HCC tissues and the normal tissues.Positive staining of aggrecan,biglycan and decorin was localized in hepatic membrane and/or pericellular matrix in normal liver tissues;however,their expression was mainly observed in the cytoplasm,cell membranes in hepatoma cells and/or pericellular matrix within HCC tissues.Semi-quantitative analysis indicated that there was a higher level of expression of aggrecan(0.43± 0.01 and 0.35±0.03,P<0.05),biglycan(0.32±0.01 and 0.25±0.01,P<0.001)and decorin(0.29±0.01 and 0.26±0.01,P<0.05)in HCC tissues compared with that in the normal liver tissues.Very weak versican positive staining was observed in hepatocytes near central vein in normal liver tissues;however there was an intensive versican distribution in fibrosis septa between the hepatoma nodules.Semi-quantitative analysis indicated that the positive rate of versican in hepatoma tissues from the HCC model group was much higher than that in the control group(33.61%and 21.28%,P <0.05).There was no positive staining in lumican and keratocan,two major KSPGs,in either normal or HCC liver tissues.CONCLUSION:CSPGs play important roles in the onset and progression of HCC,and may provide potential therapeutic targets and clinical biomarkers for this prevalent tumor in humans.

Effects of Saikosaponin-D on syndecan-2,matrix metalloproteinases and tissue inhibitor of metalloproteinases-2 in rats with hepatocellular carcinoma

OBJECTIVE:To investigate effects of Saikosaponin D(SSd) on syndecan-2,matrix metalloproteinases(MMPs) and tissue inhibitor of metalloproteinases-2(TIMP-2) in livers of rat with hepatocellular carcinoma(HCC).METHODS:Male SD rats were divided into control(n=10),model(n=20) and SSd(n=20) groups,and model and SSd groups given intragastric 0.2%(w/v) N-diethylnitrosamine to induce HCC.SSd group received 0.03%(w/v) SSd in saline.Liver samples were analysed immunohistochemically for syndecan-2,MMP-2,MMP-13 and TIMP-2 at 16 weeks.RESULTS:The model group had more malignant nodules than the SSd group;all model-group HCC cells were grade III;SSd-group HCC cells were grades I-II.Controls showed normal hepatic cell phenotypes and no syndecan-2 + staining.Syndecan-2 + staining was greater in the model group(35.2%,P≤0.001) than in controls or the SSd group(16.5%,P ≤ 0.001).The model group had more intense MMP-2 + staining than controls(0.37 vs 0.27,P≤0.01) or the SSd group(0.31 vs 0.37,P≤0.05);and higher MMP-13 + staining(72.55%) than in controls(12.55%,P≤0.001) and SSd group(20.18%,P≤0.01).The model group also had more TIMP-2 + staining(57.2%) than controls(20.9%,P≤0.001) and SSd group(22.7%,P≤0.001).Controls and SSd group showed no difference in TIMP-2 + rates.CONCLUSION:SSd inhibited HCC development,and downregulated expression of syndecan-2,MMP-2,MMP-13 and TIMP-2 in rat HCC liver tissue.