单酰甘油脂肪酶对人肝细胞癌裸鼠移植瘤的影响及其机制

目的探讨单酰甘油脂肪酶(MAGL)在人肝细胞癌(HCC)裸鼠移植瘤生长中的作用和机制。方法移植的SMMC-7721细胞株分为SMMC-7721~(WT)组(未处理)、SMMC-7721~(MAGL-KD)组(MAGL沉默)、SMMC-7721~(MAGL-OE)组(MAGL过表达)和SMMC-7721~(Vector)组(空载体转染) 4组。将27只雄性BALB/c裸鼠分为4组建立裸鼠皮下移植瘤模型,即A组(注射SMMC-7721~(WT)组细胞株,n=12)、B组(注射SMMC-7721~(MAGL-KD)组细胞株,n=5)、C组(注射SMMC-7721~(MAGL-OE)组细胞株,n=5)及D组(注射SMMC-7721~(Vector)组细胞株,n=5),其中A组又分为A1(正常饲喂,n=4)、A2[(高脂饲喂(HFD)+JZL184(MAGL的特异性抑制剂,n=4)和A3 (HFD饲喂,n=4) 3个亚组。观察并比较4组肿瘤体积变化,瘤体内增殖细胞核抗原(PCNA)、金属基质蛋白酶(MMP) 2、血浆溶血性磷脂酸(LPA)和前列腺素E2(PGE2)的表达水平。计量资料多组间比较采用单因素方差分析,进一步两两比较采用SNK-q检验。结果 MMC-7721~(WT)组、SMMC-7721~(MAGL-KD)组、SMMC-7721~(MAGL-OE)组3组间MAGL蛋白相对表达水平比较差异有统计学意义(0. 377±0. 026 vs 0. 182±0. 055 vs 0. 689±0. 019,F=33. 382,P 0. 001),SMMC-7721~(MAGL-KD)组MAGL蛋白表达水平显著低于SMMC-7721~(WT)组(P 0. 05),SMMC-7721~(MAGL-OE)组显著高于SMMC-7721~(WT)组(P 0. 05); A、B、C、D 4组间裸鼠皮下移植瘤大小比较差异有统计学意义[(4236. 125±1284. 283) mm~3vs (1883. 375±552. 977) mm~3vs (10 146. 061±1842.264) mm~3vs (4307. 452±2070. 708) mm~3,F=6. 804,P=0. 023],C组的裸鼠皮下移植瘤的生长速度比A组更快(P 0. 05),而B组比A组慢(P 0. 05); A、B、C 3组间PCNA和MMP2水平比较差异均有统计学意义(PCNA:25 843. 821±4201. 310 vs 17 426. 95±5139. 202 vs 39 753. 103±5721. 444,F=21. 482,P 0. 001; MMP2:52 841. 621±4339. 253 vs 35 511. 451±8251. 423 vs 68 274. 731±6418. 594,F=11. 526,P 0. 001),B组PCNA和MMP2水平均明显低于A组(P值均0. 05),而C组均高于A组(P值均0.05); A1、A2、A3 3组间肿瘤体积比较差异有统计学意义[(23 476. 289±483. 872) mm~3vs (18 593. 851±1385. 805) mm~3vs (37 703.198±2925. 254) mm~3,F=47. 371,P=0. 004],与A1组相比,A3组的裸鼠皮下移植瘤体积增长速度更快(P 0. 05),A2组明显受到抑制(P 0. 05); A1、A2、A3 3组间PGE2水平比较差异有统计学意义[(0. 109±0. 023)μmol/L vs (0. 056±0. 010)μmol/L vs(0. 168±0. 024)μmol/L,F=16. 492,P 0. 001],A3组PGE2水平明显高于A1组(P 0. 05),A2组明显低于A1组(P 0. 05);B、C、D 3组间PGE2水平比较差异有统计学意义[(0. 069±0. 025)μmol/L vs (0. 175±0. 023)μmol/L vs (0. 096±0. 019)μmol/L,F=31. 550,P 0. 001],B组PGE2水平明显低于D组(P 0. 05),C组明显高于D组(P 0. 05)。结论 MAGL可能通过调控PGE2促进裸鼠HCC皮下移植瘤的生长,提示MAGL可能成为未来治疗HCC的潜在靶点。     

人肝癌肺和淋巴结靶向转移细胞及裸鼠移植模型的建立

目的 克隆具有肺和淋巴结转移亲嗜性的人肝癌细胞并建立相应的裸鼠移植模型.方法 将荧光人肝癌细胞HCCLM3-R接种于4周龄的裸鼠肝脏,6周后在荧光解剖下观察并获取肺及腹腔淋巴结转移灶组织,经体外克隆培养,所获细胞分别标记为HCCLM3-R-LM1和HCCLM3-R-LnM1.接种上述两种细胞于4周龄裸鼠肝脏,观察各自肺和腹腔淋巴结转移灶荧光数量,并与肺组织连续切片中的转移灶数目进行比较.计量资料采用Wilcoxon秩和检验和Kruskal-Wallis秩和检验进行统计学分析.结果 HCCLM3-R-LM1、HCCLM3-R和HCCLM3-R-LnM1细胞接种于裸鼠肝脏后第6周,在肺和腹腔淋巴结中均能发现肿瘤转移.3株细胞接种后,裸鼠肺和腹腔淋巴结转移灶荧光面积分别为8687.00±1844.63和2570.00±318.20(P＜0.001),6457.67±832.62和10 994.33±2212.31(P＜0.001),2968.67±2571.00和24 416.00±7186.13(P＜0.001),每只裸鼠光镜下肺转移灶中位数分别为755、430、310个(P＜0.001),与荧光定量结果相吻合.结论 成功建成人肝癌肺和淋巴结亲嗜性转移细胞和裸鼠移植模型,其中HCCLM3-R-LM1细胞具有明显的肺转移特性,而HCCLM3-R-LnM1细胞具有明显的淋巴结转移特性,为肝癌器官靶向转移研究提供了理想的体内外模型.

Abstract：

Objective To establish a systematic site-specific metastatsis model of human hepatocellular carcinoma (HCC) in nude mouse.Methods HCCLM3-R cells were seeded into mice liver to establish xenograft mouse models.With the help of RFP,metastasis foci in lungs and lymph nodes in mice were detected using fluorescent stereomicroscopy and were removed.Cells derived from the metastasis foci were named HCCLM3-R-LM1 and HCCLM3-R-LnM1 respectively.HCCLM3-R-LM1 and HCCLM3-R-LnM1 cells were seeded into mice livers to analyze the lung and lymph node metastasis.Lungs of all tested mice were collected,examined by pathological evaluation and counted lung metastasis.Results Both lung and lymph node metastasis were found in HCCLM3-R-LM1,HCCLM3-R and HCCLM3-R-LnM1 cells and a significant difference was found between the lung and the lymph node metastasis levels in the three cells.The fluorescent areas (pixels) of lung and lymph node metastasis were 8687.00 ± 1844.63 versus 2570.00 ±318.20 (P = 0.0031) in HCCLM3-R-LM1 cells,6457.67±832.62 versus 10 994.33±2 212.31(P=0.0036) in HCCLM3-R cells,and 2968.67 ± 2571.00 versus 24 416.00 ± 7 186.13 (P = 0.0094) in HCCLM3-R-LnM 1 cells,respectively.The middle numbers of microscopic lung metastatic foci were 775,430 and 310in HCCLM3-R-LM1,HCCLM3-R and HCCLM3-R-LnM1 cells (P＜0.001),respectively,consist with the results quantified by RFP.Conclusion We established the systematic site-specific metastasis models which demonstrates lung- and lymph node-specific metastasis potential in nude mice and can be used as a model for researches on site-specific metastasis of HCC.     

外周血甲胎蛋白mRNA定量与裸鼠肝癌术后复发转移的关系

目的 研究外周血中胎蛋白信使核糖核酸(AFP mRNA)水平与原发性肝癌根治性切除术后复发转移的关系。方法 裸鼠肝内原位接种裸鼠人肝癌转移模型LCI-D20肿瘤组织,接种后第10天切除移植瘤,切除后第2天用不同剂量干扰素α-1b(IFNα-1b )治疗,治疗35 d后取外周血1 ml,用TaqMan实时定量逆转录－聚合酶链反应(RT-PCR)技术检测AFP mRNA水平,同时观察肿瘤复发转移情况。结果 对照组裸鼠术后肝内复发率和肺转移率均为100%(12/12),外周血AFP mRNA阳性率为100%。小剂量IFNα-1b治疗组肝内复发率62.5%(5/8),复发瘤体积小于对照组(25 mm~3±2mm~3对1143mm~3±3mm~3,t=9.27,P＜0.01),无肺转移,外周血AFP mRNA阳性率87.5%(7/8),水平低于对照组[(85±6)copies/μg对(955±2)copies/μg,t＝4.33,P＜0.01)。大剂量IFNα-1b治疗组肝内复发率为12.5%(1/8),体积仅0.5mm~,无肺转移,外周血AFP mRNA均阴性(x~2=11.67,P＜0.01)。结论 外周血AFP mRNA可作反映肝癌复发转移的敏感指标,TaqMan实时定量RT-PCR技术检测循环血肝癌细胞灵敏、简便、精确度高。     

尿激酶型纤溶酶原激活剂受体的表达对肝癌细胞株体外侵袭迁移的影响

目的观察尿激酶型纤溶酶原激活剂受体(uPAR)的表达对肝癌细胞体外侵袭迁移能力的影响。方法通过Boyden小室肿瘤细胞体外侵袭实验检测肝癌细胞株Hep-3B及SMMC-7721体外侵袭迁移能力,用流式细胞术检测Hep-3B及SMMC-7721的uPAR,通过流式细胞分选技术从具有较强转移能力的SMMC-7721中分选出uPAR+细胞株和uPAR-细胞株,通过Boyden小室检测uPAR+组和uPAR-组SMMC-7721细胞的体外侵袭迁移能力。结果 SMMC-7721体外侵袭迁移能力明显强于Hep-3B(P<0.01);SMMC-7721中uPAR+细胞株占45.5%,Hep-3B中uPAR+细胞株占0.05%,两者相比,P<0.01;从SMMC-7721中分选出的uPAR+组和uPAR-组细胞纯度分别为90%和97%,uPAR+组细胞的体外侵袭迁移能力较uPAR-组细胞明显增强(P<0.01)。结论 uPAR的表达不但和肝癌细胞的体外侵袭迁移能力密切相关,且可能赋予了肝癌细胞强大的侵袭迁移能力。     

MMP-2和ICAM-1在裸鼠体内塞来昔布抑制肝癌组织中的表达

目的:研究机体内部选择性环氧合酶-2(COX-2)抑制剂对肝细胞癌的抑制作用.方法:将三种肝癌细胞株HepG2、BEL-7402和SMMC-7721分别接种于6周龄裸鼠肝脏被膜下;将接种了不同肝癌细胞株的裸鼠分别分为3组,阴性对照组给予生理盐水灌胃,实验组给予塞来昔布灌胃,阳性对照组进行生理盐水灌胃的同时使用阿霉素腹腔注射;3 wk后对裸鼠肝脏肿瘤取材、免疫组织化学法观察肿瘤组织中基质金属蛋白酶-2(MMP-2)及其抑制剂(TIMP-2)以及细胞间黏附因子-1(ICAM-1)的表达.结果:在肝脏被膜下接种了HepG2、BEL-7402和SMMC-7721肝癌细胞株的裸鼠中,应用塞来昔布的裸鼠肿瘤组织中MMP-2的表达下降(P<0.05),MMP-2的表达增加(P<0.05),TIMP-2/MMP-2比值增加.在肝脏被膜下接种了BEL-7402和SMMC-7721肝癌细胞株的裸鼠中,应用塞来昔布的裸鼠肿瘤组织中ICAM-1表达下降.结论:塞来昔布在机体内部可能具有抑制肝癌细胞转移和改善预后的作用.     

VEGF促进肝癌SMMC-7721细胞侵袭性的自分泌机制

目的:探讨促血管内皮生长因子(VEGF)对人肝癌细胞SMMC-7721侵袭力以及对该细胞中基质金属蛋白酶9(MMP-9)的影响,初步研究VEGF对肿瘤侵袭和转移的影响及可能的作用机制.方法:使用VEGF体外培养人肝癌SMMC-7721细胞,通过细胞体外侵袭实验检测细胞侵袭能力的改变,再分别使用30μg/L、10μg/LVEGF培养人肝癌SMMC-7721细胞,以正常培养人肝癌SMMC-7721细胞为空白对照组.使用半定量RT-PCR和Western blot法对3组细胞中MMP-9的mRNA和蛋白表达水平进行分析.结果:细胞体外侵袭实验显示,外加VEGF培养后,细胞侵袭力明显增强(P0.01);MMP-9mRNA和蛋白的表达在外加VEGF组中要明显高于空白对照组(0.479±0.025,0.665±0.024vs 0.315±0.022;0.521±0.026,0.662±0.026vs 0.366±0.025,均P<0.01),且高浓度和低浓度组之间也有明显差别.结论:肝癌SMMC-7721细胞系中存在有自分泌机制,VEGF可通过自分泌机制上调肝癌细胞的MMP-9表达,进而促进肿瘤的浸润转移.     

黄芩苷对肝癌细胞SMMC-7721JAK-STAT-号通路STAT3的影响

目的:探讨黄芩苷对肝癌细胞SMMC-7721JAK-STAT信号通路STAT3的影响.方法:将肝癌细胞SMMC-7721分为4组:对照组、黄芩苷组、AG490组、黄芩苷+AG490组.应用RT-PCR法检测各组肝癌细胞SMMC-7721中STAT3 mRNA表达,Western blot法检测肝癌细胞SMMC-7721...     

牛蒡子苷元对肝癌侵袭转移的影响

目的:研究牛蒡子苷元(arctigenin,ARG)对肿瘤黏附、侵袭、转移的影响.方法:体外实验分别采用MTT法、Transwell 法检测ARG对SMMC-7721细胞黏附、侵袭和转移的影响;体内实验采用裸鼠肺转移瘤模型,检测ARG对SMMC-7721细胞肺转移的影响.结果:与空白对照组相比,ARG作用后SMMC-7...     

缺氧环境中黏着斑激酶对SMMC-7721细胞侵袭能力的影响

目的 研究缺氧对人肝癌细胞SMMC-7721黏着斑激酶(FAK)表达的影响以及FAK表达对SMMC-7721细胞侵袭能力的影响.方法 通过1%体积分数O2的低氧培养建立人肝癌细胞SMMC-7721物理缺氧模型,Western blot检测FAK的表达.构建针对FAK mRNA的干扰质粒pshRNA-FAK及阴性对照质粒pGensil-2,并将其转染至SMMC-7721细胞,G418筛选稳定转染细胞株.Western blot检测FAK蛋白表达的变化,细胞迁移和侵袭实验检测缺氧条件下细胞迁移和侵袭能力的改变.在正常条件下将FAK真核表达质粒pcDNA3-FAK转染至SMMC-7721细胞,观测其侵袭能力的改变.根据数所资料的不同分别采用t检验、单因素方差分析,LSD法及Dunnett法进行统计学处理. 结果低氧培养的SMMC-7721细胞FAK蛋白表达水平逐渐升高,24 h后较0 h时明显升高(P<0.01).SMMC-7721细胞稳定转染pshRNA-FAK后,FAK蛋白表达显著下降,抑制率达74.6%±5.1%,在正常及缺氧条件下都对FAK表达有显著抑制作用.细胞迁移实验结果显示,缺氧显著促进SMMC-7721细胞迁移能力(t=18.66,P<0.01),侵袭实验结果与迁移实验结果一致.转染pshRNA-FAK对促进SMMC-7721细胞在缺氧环境中的迁移能力有显著抑制作用,透膜细胞数(353±36)个较对照组(392±31)个明显降低(F=173.983,P<0.05);细胞侵袭实验显示,转染pshRNA-FAK对促进SMMC-7721细胞侵袭能力有显著抑制作用,透膜细胞数(160±12)个较对照组(194±13)个明显降低(F=59.674,P<0.05).同时转染真核表达质粒pcDNA3-FAK显著促进SMMC-7721细胞侵袭能力.结论 缺氧促进SMMC-7721细胞侵袭可能与FAK表达水平升高相关,FAK表达的上调可能是缺氧促进肝癌细胞侵袭转移的机制之一.     

同步辐射成像技术应用于HCCLM3细胞裸鼠肝脏移植瘤新生血管形态学研究的初步实验

目的 应用同步辐射微血管造影技术进行裸鼠离体肝细胞癌肿瘤新生血管的形态学研究. 方法 建立高转移人肝癌细胞HCCLM3裸鼠肝脏移植瘤模型.肝脏移植瘤模型建立第28天,取模型鼠6只,随机分为2组(每组3只).第1组裸鼠经腹腔内注射戊巴比妥钠麻醉后开腹,经下腔静脉留置管,手动推注硫酸钡悬浮液,直至肝脏及肝肿瘤表面血管呈白色,结扎肝脏的血管和胆管后切除肝脏,浸泡在甲醛溶液里,准备成像.离体裸鼠肝癌新生血管成像在上海光源(SSRF)X射线成像与生物医学应用光束线站(BL13W)进行.第2组裸鼠腹腔内注射戊巴比妥钠麻醉后,开腹取肝肿瘤标本,行病理学检查,包括HE染色及免疫组织化学CD31、CD34和F8染色. 结果 同步辐射微血管造影结合显微CT获得了高质量的肿瘤新生血管图像,图像显示正常肝血管结构被迅速生长的肿瘤组织取代,可以清晰观察到肿瘤新生血管的形态特征及生长状况,肿瘤周围血管丰富、扭曲,瘤内血管稀疏,与免疫组织化光学显微图像所示肿瘤新生血管分布特征相似.同步辐射成像技术能分辨肿瘤内部最细的血管直径约20μm. 结论 采用硫酸钡作为造影剂,利用同步辐射微血管造影技术显示裸鼠肝肿瘤新生血管的方法可行.     

不同转移潜能人肝癌细胞株趋化因子受体谱差异表达

目的对比观察不同转移潜能人肝癌细胞株趋化因子受体谱差异性表达。方法Pre- mier软件设计18对趋化因子受体引物,RT-PCR分析SMMC-7721、MHCC97-L、MHCC97-H和HCCLM6细胞侵袭转移潜能逐渐增强的人肝癌细胞株趋化因子受体谱。结果4组不同转移潜能细胞株趋化因子受体表达谱存在明显差异（P＜0．01）,其中CCR10、CXCR4、CXCR6表达随转移潜能增加逐渐降低。HCCLM6表达谱中CCR3、CCR4、CCR10、CCR12及XCR1比SMMC-7721表达明显降低甚至缺失（P＜0．01）,而CXCR1（P=0．006）、CXCR5（P=0．003）表达高于低转移潜能组SMMC-7721。MHCC97-H和MHCC97-L比较,除CXCR2、CXCR6、XCR1外差异均有统计学意义,其中CCR1（P=0．002）、CCR2（P=0．004）、CCR5（P=0．046）表达高于MHCC97- L。CXCR4在模板减量时只能在SMMC-7721组检测到。结论高低转移潜能肝癌细胞株趋化因子受体表达在mRNA水平存在差异性表达,与肝癌细胞株差异性转移潜能相关。     

Establishment of a hepatocellular carcinoma cell line with unique metastatic characteristics through in vivo selection and screening for metastasis-related genes through cDNA microarray

PURPOSE: To establish a hepatocellular carcinoma (HCC) cell line from lung metastatic lesions of human HCC in nude mice so as to provide a suitable model for the study of lung-metastasis-related molecular mechanisms. METHODS: HCC clone cells MHCC97-H were inoculated into BALB/c nude mice, and the pulmonary metastatic lesions were harvested and re-implanted into nude mice for the second round of in vivo selection. The same procedure was repeated twice. A new cell line from the third round of lung metastases was established. RESULTS: A human HCC cell line with unique metastatic characteristics was established by in vivo selection. This cell line, designated as HCCLM3, was polygonal epithelial cell with hypotriploid karyotype and population doubling time of 34.9 h. The cells were positive for alpha fetoprotein (AFP), albumin, cytokeratin 8 (CK8), and negative for hepatitis B surface antigen (HBsAg) by immunocytochemistry. Fluorescence polymerase chain reaction (PCR) showed HBV DNA integration in the cellular genome. When 5 x 10(6) cells were injected subcutaneously into nude mice, tumorigenicity was 100%, with a latency period of 11+/-1 days. Five weeks after s.c. injection, the pulmonary metastatic rate was 100%, the median number of lung metastases being 121 per mouse. After orthotopic implantation of tumor tissue into nude mouse liver for 35 days, widespread loco-regional and distant metastases occurred, with 100% abdominal wall metastases, 80% intra-abdominal cavity metastases, 100% intrahepatic metastases, 70% diaphragm metastases, and 100% pulmonary metastases. The median number of lung metastatic lesions was 268 per mouse. Gene expression profile of HCCLM3 was compared by cDNA microarray with MHCC97-L, a clonal cell strain from the same parental cell line but with low metastatic potential; 25 differentially expressed genes were identified, 18 of which showed decreased expression and seven increased expression in HCCLM3, including the decreased expression of cell cycle control gene Rb2, mismatch repair gene hMSH2, and signal transduction gene protein kinase C beta2, and increased expression of signal transduction gene MAP kinase, kinase 6. CONCLUSIONS: A new HCC cell line characterized by high pulmonary metastases via s.c. and orthotopic inoculation was established, which provides a new model for the study of liver cancer metastasis. Its gene expression profile could help in the understanding of the mechanism of metastasis and provide potential targets for anti-metastasis intervention.     

Proteinase-activated receptor 2 promotes tumor cell proliferation and metastasis by inducing epithelial-mesenchymal transition and predicts poor prognosis in hepatocellular carcinoma

AIM To clarify the role of proteinase-activated receptor 2(PAR2) in hepatocellular carcinoma, especially in the process of metastasis.METHODS PAR2 expression levels were assessed by qRT-PCR and immunohistochemistry(IHC) in patient tissues and in hepatocellular carcinoma cell lines SMMC-7721 and Hep G2. Cell proliferation and metastasis were assessed both in vitro and in vitro. Immunoblotting was carried out to monitor the levels of mitogen-activated protein kinase(MAPK) and epithelial-mesenchymal transition markers.RESULTS The prognosis was significantly poorer in patients with high PAR2 levels than in those with low PAR2 levels. Patients with high PAR2 levels had advanced tumor stage(P = 0.001, chi-square test), larger tumor size(P = 0.032, chi-square test), and high microvascular invasion rate(P = 0.037, chi-square test). The proliferation and metastasis ability of SMMC-7721 and Hep G2 cells was increased after PAR2 overexpression, while knockdown of PAR2 decreased the proliferation and metastasis ability of SMMC-7721 and Hep G2 cells. Knockdown of PAR2 also inhibited hepatocellular carcinoma tumor cell growth and liver metastasis in nude mice. Mechanistically, PAR2 increased the proliferation ability of SMMC-7721 and Hep G2 cells via ERK activation. Activated ERK further promoted the epithelial-mesenchymal transition of these cells, which endowed them with enhanced migration and invasion ability. CONCLUSION These data suggest that PAR2 plays an important role in the proliferation and metastasis of hepatocellular carcinoma. Therefore, targeting PAR2 may present a favorable target for treatment of this malignancy.     

Growth-inhibiting effects of taxol on human liver cancer in vitro and in nude mice

AIM To investigate the effects of taxol on SMMC-7721 human hepatoma and its mechanisms. MLETHODS In vitro cell growth was assessed by trypan blue exclusion method. Experimental hepatoma model was established by seeding SMMC-7721 cells subcutaneously into Balb/c (nu/nu) nude mice. In vivo tumor growth was determined by measurement of tumor diameter with Vernier calipers. The syntheses of DNA,RNA and protein were analyzed by incorporation of 3H-thymidine, 3H-uridine and 3H-leucine respectively. Using light and electron microscopes to observe the morphological changes of cells including mitosis and apoptosis. RESULTS Taxol was effective against SMMC 7721 human hepetoma cell growth in the ranges of 2.5 nmol/L - 10 nmol/L with mitotic arrest and apoptosis in vitro. DNA, RNA and protein syntheses in cells were also obviously suppressed by in vitro treatment of taxol for 72 h. Taxol at 2.5 nmol/L reduced 3H-thymidine uptake to about 34% of the control value (P＜0.05). Increasing the dose of taxol to 20 nmol/L resulted in a greater decrease in 3Hthymidine incorporation to 60% of the control value (P＜0.01). At a concentration of 20 nmol/L, the 3H-uridine and 3H-leucine uptakes were reduced to 52% (P＜0.05) and 63%(P＜0.01), respectively. In vivo, taxol significantly inhibited SMMC-7721 tumor growth at 10 mg/kg, i.p., once daily for 10 d. A more than 90% decrease in tumor volume was observed by day 11 (P＜0.01) similarly with mitotic arrest and cell apoptosis. CONCLUSION Taxol has a marked anticancer activity in SMMC-7721 human hepatoma both in vitro and in nude mice. Its mechanisms might be associated with mitotic arrest, subsequently,apoptosis of the hepatoma cells. No obvious toxicity was observed with in vivo administration of taxol.     

Expression of angiostatin cDNA in human hepatocellular carcinoma cell line SMMC-7721 and its effect on implanted carcinoma in nude mice

AIM: To transfect murine angiostatin cDNA into human hepatocellular carcinoma cell line SMMC-7721 and to investigate its effects on implanted carcinoma in nude mice. METHODS: A eukaryotic expression vector of pcDNA3.1-mAST containing murine angiostatin was constructed. Then pcDNA3.1-mAST plasmid was transfected into cell line SMMC-7721 by Lipofectamine. The resistant clone was screened by G418 filtration and identified by RT-PCR and Western blotting. Nude mice were divided into three groups of 10 each. Mice in blank control group were only injected with SMMC-7721 cells. Mice in vector control group were injected with SMMC-7721 cells transfected with pcDNA3.1 (+) vector, whereas mice in angiostatin group were injected with SMMC-7721 cells transfected with pcDNA3.1-mAST plasmid. Volume, mass and microvessel density (MVD) of the tumors in different groups were measured and compared. RESULTS: Murine angiostatin cDNA was successfully cloned into the eukaryotic expression vector pcDNA3.1 (+). pcDNA3.1-mAST was successfully transfected into SMMC-7721 cell line and showed stable expression in this cell line. No significant difference was observed in the growth speed of SMMC-7721 cells between groups transfected with and without angiostatin cDNA. Tumor volume, mass and MVD in the angiostatin group were significantly lower than those in the blank control group and vector control group (P<0.01). The inhibitory rate of tumor reached 78.6%. Mass and MVD of the tumors only accounted for 34.6% and 48.9% respectively of those in the blank control group. CONCLUSION: Angiostatin cDNA could be stably expressed in human hepatocellular carcinoma cell line SMMC-7721 without obvious inhibitory effects on the growth of SMMC-7721 cells. When implanted into nude mice, SMMC-7721 cells transfected with angiostatin cDNA show a decreased tumorigenic capability. It suggests that angiostatin can inhibit tumor growth through its inhibition on angiogenesis in tumors.     

脂质体法转染人肿瘤坏死因子-α基因对裸鼠人肝癌移植瘤的抑制效应及其机制

背景：外源性肿瘤坏死因子（TNF）-α联合化疗药物对肿瘤的疗效较单独应用更佳,为肿瘤治疗提供了新的方向。目的：对裸鼠人肝癌移植瘤模型行脂质体介导的TNF-α基因瘤内转染,研究肝癌移植瘤的生长抑制情况及其机制。方法：经脂质体介导,以真核表达质粒pSVK3-TNF-α分别转染人肝癌细胞株SMMC-7721和裸鼠皮下SMMC-7721细胞移植瘤。测定SMMC-7721细胞的TNF-α浓度,甲基噻唑基四唑（MTT）法测定细胞杀伤率,流式细胞仪和原位末端标记（TUNEL）法检测细胞周期和凋亡情况。结果：TNF-α转基因治疗裸鼠人肝癌移植瘤结束第5d,移植瘤体积为（75.28±35.35）mm^3,显著低于对照组的（326.45±103.64）mm^3（P〈0.05）。TNF-α基因体外转染SMMC-7721细胞24、48、72h后,基因转染组每106个细胞的TNF-α表达量分别为（1680±187）pg、（1702±205）pg和（1650±164）pg,细胞杀伤率分别为（37.1±2.4）%、（79.4±4.3）%和（84.2±4.6）%。基因转染72h后,SMMC-7721细胞增殖指数为（30.5±3.2）%,显著低于对照组的（46.1±3.9）%（P〈0.05）;凋亡指数为（10.0±2.1）%,显著高于对照组的（2.7±0.4）%（P〈0.01）。结论：脂质体介导的TNF-α基因转染裸鼠人肝癌移植瘤可明显抑制肿瘤生长,其机制可能为影响肿瘤细胞生长周期以及诱导肿瘤细胞凋亡。     

塞来昔布联合 NK 细胞对裸鼠人肝癌皮下移植瘤生长的影响

目的：观察塞来昔布联合NK细胞对裸鼠人肝癌细胞SMMC-7721皮下移植瘤生长的影响,并探讨其可能的作用机制。方法选择裸鼠40只,制备人肝癌细胞SMMC-7721移植瘤模型,随机分为对照组、NK细胞组、塞来昔布组及联合干预组各10只。 NK细胞组瘤内注射NK细胞悬液0．6 mL,每7 d注射1次,共注射5次;塞来昔布组从接种后第3天起给予塞来昔布100 mg/kg灌胃,每天1次,连续35 d;联合干预组同时给予塞来昔布和NK细胞,给药剂量及途径与单用组相同;对照组灌胃和瘤内注射等量生理盐水。35 d后切取移植瘤组织计算体积,称取瘤质量,并计算抑瘤率;TUNEL法评价肿瘤细胞凋亡情况,免疫组化法检测肿瘤内VEGF、Bax、Bcl-2、caspase-3、Ki-67、NF-κB的阳性表达。结果联合干预组移植瘤体积、肿瘤质量均明显低于单用组（ P均＜0．05）,抑瘤率、凋亡指数明显高于单用组（ P均＜0．05）。联合干预组移植瘤中VEGF、Bcl-2、NF-κB、Ki-67表达明显低于单用组（ P均＜0．05）,Bax、caspase-3表达明显高于单用组（P均＜0．05）。结论塞来昔布联合NK细胞可明显抑制裸鼠人肝癌细胞SMMC-7721皮下移植瘤的生长;其作用机制可能是通过促进凋亡级联通路上Bax、caspase-3的表达,抑制VEGF、Bcl-2、NF-κB、Ki-67的表达而实现。