雷公藤内酯醇抑制胰腺癌细胞生长及血管生成的实验研究

目的 探讨雷公藤内酯醇(TL)对胰腺癌细胞生长及肿瘤新生血管生成的抑制作用.方法 采用CCK-8试剂盒检测TL对胰腺癌SW1990细胞的生长抑制作用;采用TUNEL法检测TL对细胞凋亡的诱导作用;观察尾静脉注射TL对裸鼠移植瘤生长抑制作用和对瘤组织VEGF表达、微血管密度(MVD)的影响.结果 TL呈浓度和时间依赖性抑制SW1990细胞增殖,160 mg/ml的TL干预SW1990细胞24 h,细胞抑制率达50.6%,细胞凋亡率从对照组的9.6%升高到45.1%(P<0.01);TL0.5 mg/kg体重瘤内注射对移植瘤的抑瘤率达89.9%,瘤组织VEGF表达减少,MVD从36.25±8.64减少到9.87±3.34(P<0.01).结论 TL可显著抑制胰腺癌细胞增殖并诱导细胞凋亡;通过抑制肿瘤新生血管生成可抑制裸鼠SW1990细胞移植瘤的生长.     

人胰腺癌细胞株PANC1裸鼠原位模型的建立及磁共振监测

目的 建立一种稳定的人胰腺癌裸小鼠原位移植瘤模型,并探讨无创的磁共振(MRI)对其监测的应用价值.方法 人胰腺癌细胞株PANC1体外常规传代后建立裸鼠皮下种植瘤模型,将皮下种植瘤制成细胞悬液,植入20只BALB/C-nn裸鼠的胰腺包膜下构建人胰腺癌原位移植模型;通过MRI检查监测模型的成瘤率、成瘤时间、肿瘤生长速度、肿瘤形态、信号变化等特征,于第7周末取肿瘤组织行病理学检查.结果 接种后15 d,7只(35%)荷瘤鼠在MRI上显示成瘤,至接种后27 d,成瘤率为100%.肿瘤信号与邻近组织相比,90%(18/20)病灶T1WI呈均匀稍低信号,10%(2/20)呈等信号;75%(15/20)在T2WI呈均匀高信号.移植后2、3、4、5、6、7周经MRI测量的移植瘤体积分别为(12.6±2.4)mm3、(94.3±11.2)mm3、(175.9±82.5)mm3、(395.8±126.6)mm3、(1290.2±167.2)mm3、(1583.4±87.4)mm3.病理学检查确诊为胰腺低分化腺癌,并保持原发瘤的生物学特征.结论 人胰腺癌细胞株PANC1移植瘤制成的细胞悬液种植裸小鼠胰腺包膜下制备胰腺癌模型符合人胰腺癌的特征,且易于无创监测,为临床研究提供了一个有效、稳定的体内实验体系.     

西咪替丁抑制人肠癌裸鼠移植瘤

目的：研究西咪替丁对人结肠癌裸鼠移植瘤生长的抑制作用及机制。方法：建立人结肠癌裸鼠皮下移植瘤模型。随机分2组,每组5只实验鼠。肿瘤种植前3 d开始分别皮下注射生理盐水(对照组)或西咪替丁(治疗组),每天1次,观察成瘤时间及瘤体成长情况。肿瘤种植后第7周处死实验鼠,测定瘤体大小,并用免疫组化方法测定肿瘤组织内微血管密度(MVD)和血管内皮生长因子(VEGF)的表达。结果：治疗组肿瘤体积明显小于对照组;治疗组肿瘤组织中的VEGF表达程度和MVD计数亦明显低于对照组。结论：西咪替丁通过抑制VEGF表达,减少血管生成,从而抑制肿瘤生长。     

原位注射法建立人胰腺癌SW1990裸鼠种植瘤模型及高频内镜超声探头对其的监测

目的 建立裸小鼠人胰腺癌原位种植瘤模型,探索监测种植瘤生长的方法.方法 将对数生长期的人胰腺癌细胞株SW1990制备成细胞悬液,原位注射于Balb/c-nu裸小鼠胰腺尾部包膜下,利用高频内镜超声(EUS)探头体表观察肿瘤结节的生长及声像图像.结果 20只裸小鼠均接种成功,1只裸鼠于接种后25 d时死亡.接种后14 d,EUS检查的瘤体大小为(8.09±2.61)mm3,肿瘤结节呈均质低回声,边界清楚,周边有包膜及声晕,形态规则,30%的肿瘤结节周边可见低速环绕彩色血流信号;接种后28 d,瘤体增大至(12.40±3.51)mm3,70%的肿瘤结节呈不规则形,部分为分叶状,肿块呈低回声,不均质,未见液化坏死区,70%的肿瘤结节周边可见低速环绕彩色血流信号.结论 原位注射法是建立裸小鼠人胰腺癌原位种植瘤模型较理想的方法,操作简便,成瘤率高;高频内镜超声显像是可靠的监测胰腺原位种植瘤的手段.     

光动力疗法对胰腺癌移植瘤的疗效及其时-效关系

目的 探讨光动力疗法(PDT)对人胰腺癌裸鼠移植瘤的疗效及其时-效关系.方法 将人胰腺癌细胞SW1990皮下种植后形成的瘤块剪成1 mm3组织块再移植至36只裸鼠皮下,待皮下移植瘤直径达0.8～1 cm时按随机分组法分为3组:荷瘤对照组、光敏剂组(腹腔内注射Photosan 2 mg/kg体重)、光动力组(腹腔内注射Photosan 2 mg/kg体重,48 h后予激光照射),每组12只.每周2次测量肿瘤大小,3周后取瘤称瘤重,计算瘤体积及抑瘤率.结果 PDT组治疗后第6天瘤体积为(0.24±0.15)cm3,显著小于荷瘤对照组的(0.43±0.18)cm3和光敏剂组的(0.39±0.15)cm3(P＜0.05),并随着时间延长,差异更加显著.但治疗后15 d起,PDT组移植瘤体积又开始增大.治疗21 d后,PDT组瘤重为(0.69±0.23)g,显著小于荷瘤对照组的(1.65 ±0.21)g和光敏剂组的(1.62±0.12)g(P＜0.05).PDT组抑瘤率为58.18%,显著高于光敏剂组的1.80%(P＜0.05).结论 PDT对胰腺癌具有显著的抑制作用,起效快,但单用疗效维持时间不长.     

Inhibitory effect of arsenic trioxide on angiogenesis and expression of vascular endothelial growth factor in gastric cancer

INTRODUCTION Arsenic has been used since ancient times as a therapeutic agent. However, until recently its use in modern medicine has been restricted to the treatment of a limited number of parastic infections. Since the early 1990s, arsenic trioxide (As2…     

Antiangiogenic therapy for human pancreatic carcinoma xenografts in nude mice

AIM: To investigate the anti-tumor effects of antiangiogenic therapy (a combination of TNP-470, an antiangiogenic compound, with gemcitabine, an antimetabolite) on human pancreatic carcinoma xenografts and its mechanism. METHODS: A surgical orthotopic implantation (SOI) model was established by suturing small pieces of SW1990 pancreatic carcinoma into the tail of pancreas in nude male mice. Mice then received either single therapy (n = 24) or combined therapy (n = 32). Mice receiving single therapy were randomly divided into control group, G100 group receiving 100 mg/kg gemcitabine IP on d O, 3, 6 and 9 after transplantation, and T30 group receiving 30 mg/kg TNP-470 s.c on alternate days for 8 wk. Mice receiving combined therapy were randomly divided into control group, T15 group, G50 group and combination group (TNP-470 30 mg/kg and gemcitabine 50 mg/kg). Animals were killed 8 wk after transplantation. Transplanted tumors, liver, lymph node and peritoneum were removed. Weight of transplanted tumors, the T/C rate (the rate of mean treated tumor weight to mean control tumor weight), change of body weight, metastasis rate, and 9-wk survival rate were investigated. Tumor samples were taken from the control group, T30 group, G100 group and combination group. PCNA index (PI) and microvessel density (MVD) were investigated by immunohistochemical staining for PCNA and factor VIII, respectively. RESULTS: There was a significant inhibitory effect on primary tumor growth of pancreatic carcinoma in G100 group, compared to T30 group, whereas tumor metastasis was significantly inhibited in T30 group compared to G100 group. There was no significant improvement in survival rate in these two groups. No significant inhibitory effect on tumor growth and metastasis in T15 group and G50 group. However, significant anti-tumor and anti-metastatic effects were observed in the combination group with a significant improvement in survival rate. The inhibitory effect on tumor growth in combination group enhanced 2 times in comparison with G50 group and 5 times in comparison with T15 group. Moreover, 25% of the animals hearing tumors were cured by the combination therapy. The levels of MVD and PI were 14.50±5.93 and 0.41±0.02,12.38±1.60 and 0.30±0.07, 7.13±2.99 and 0.37±0.03, and 5.21±1.23 and 0.23±0.02 respectively in the control group, G100 group, T30 group and combination group. A significant inhibitory effect on PI level and MVD level was observed in G100 group and T30 group respectively whereas both MVD and PI levels were significantly inhibited in the combination group (P<0.05). CONCLUSION: Antiangiogenic therapy shows significant anti-tumor and anti-metastatic effects, and is helpful to reduce the dosage of cytotoxic drugs and the side effects. These effects are related to the antiangiogenic effect of TNP-470 and cytotoxic effect of gemcitabine.     

Effect of 2-（8-hydroxy-6-methoxy- 1-oxo- 1H-2-benzopyran-3yl） propionic acid in combination with carboplatin on gastric carcinoma growth in vivo

AIM： To investigate the effects of 2-（8-hydroxy-6- methoxy-l-oxo-lH-2-benzopyran-3-yl） propionic acid （NM-3） alone and in combination with carboplatin on tumor growth and apoptosis in mouse models of human gastric cancer constructed by subcutaneous implantation of histologically intact tumor tissue.
METHODS： Human gastric cancer SGC-7901 tissues were implanted into the dorsal subcutis of nude mice. One week after tumors reached to a volume of 50-100 mm3 for around 1 wk, these mice were randomly divided into 8 groups （n = 10）. NM-3 was injected peritoneally at the dose of 10 mg/kg, 20 mg/kg or 40 mg/kg every other day for 5 wk, combined with carboplatin （5 mg/kg） every third day for 4 wk. As controls of combined treatment, another 4 groups of mice were injected with either NM-3 at 10 mg/kg, 20 mg/kg or 40 mg/kg, or with carboplatin alone （5 mg/kg）. The control mice received normal saline. Tumor weight, tumor growth inhibition （TGI）, and intratumoral microvessel density （MVD） were evaluated. Apoptosis of human gastric cancer was detected by TUNEL method and flow o/tometry analysis, respectively.
RESULTS： The mean tumor volume （692.40 ± 58.43 mm3, 548.30 ± 66.02 mm3, 382.13 ± 43.52 mm3） after treatment with carboplatin combined NM-3 at the dose of 10 mg/kg, 20 mg/kg or 40 mg/kg was lower than that after treatment with either NM-3 at the dose of 10 mg/kg, 20 mg/kg or 40 mg/kg or with carboplatin alone. Compared with the normal saline group, NM-3 administered at 10 mg/kg, 20 mg/kg or 40 mg/kg significantly reduced the tumor weight in these groups （P 〈 0.05）. Carboplatin used alone at 5 mg/kg showed minimal effects. But NM-3 in combination with carboplatin had greater effects of tumor weight than either NM-3 or carboplatin alone. NM-3 alone at the dose 10 mg/kg or in combination with carboplatin had no obvious effects on body changes. Two mice died of diarrhea in each of the two groups treated with 40 mg/kg NM-3 or with 40 mg/kg NM-3 in combination with carboplatin. A     

康莱特注射液与光动力疗法联合治疗大鼠胰腺移植瘤

目的 探讨康莱特注射液与光动力疗法(PDT)联合应用对裸鼠胰腺癌移植瘤生长的抑制作用.方法 将人胰腺癌细胞株SW1990移植至裸鼠皮下制备皮下移植瘤模型.60只荷瘤鼠按随机数字法分为6组:对照组,不予任何治疗;康莱特1组,激光照射前一天开始从尾静脉注射康莱特注射液1.25 g/kg体重,连续10 d;康莱特2组,同上法注射康莱特注射液2.5 g/kg体重;光动力(PDT)组,腹腔内注射Photosan 2 mg/kg体重,48 h后予激光照射;联合1组,治疗方法采用康莱特1组+PDT组;联合2组,治疗方法为康莱特2组+PDT组.每组10只.每周2次测量肿瘤大小.PDT后14 d处死动物,取瘤块称重,计箅抑瘤率.结果 对照组、康莱特1组、康莱特2组、PDT组、联合1组和联合2组治疗后14 d的瘤体积分别为(550.08±52.46)mm3、(519.71±46.44)mm3、(405.29±38.67)mm3、(199.27±37.37)mm3、(107.47±14.13)mm3和(75.58±12.53)mm3;瘤重分别为(0.82±0.08)g、(0.77±0.06)g、(0.61±0.06)g、(0.41±0.05)g、(0.28±0.04)g和(0.16±0.04)g.2个联合组的肿瘤体积和瘤重明显小于其他各组(P＜0.05);联合1组抑瘤率从PDT组的50%上升到65.9%,联合2组上升到80.5%.结论 康莱特与PDT联合应用可明显抑制移植瘤体积,有协同增效作用.     

靶向重组腺病毒介导Hsp70基因表达对大鼠胰腺癌移植瘤的抑制作用

目的:观察重组腺病毒Ad5-pCEA-Hsp70介导的Hsp70基因表达对大鼠胰腺癌移植瘤生长的影响,并分析其相关机制.方法:建立大鼠胰腺癌皮下移植瘤模型,随机分为3组,分别给予Ad5-pCEA-Hsp70、Ad5-control以及PBS进行治疗.对比不同时间点3组肿瘤大小,评价抑瘤效果:通过ELISA的方法检测外周血Hsp70蛋白含量及细胞因子INF-γ、TNF-α、IL-6的含量;取动物的移植瘤常规HE染色,观察淋巴细胞浸润情况;分离动物脾脏单核细胞,通过流式细胞仪检测CD83+细胞比例,并观察脾淋巴细胞对体外培养的大鼠胰腺癌细胞的杀伤能力.结果:治疗后第4、6、8周,Ad5-pCEA-Hsp70组肿瘤体积分别与Ad5-control组及PBS组相比(724.4mm3±81.6mm3vs901.3mm3±103.9mm3、987.5mm3±126.0mm3;681.3mm3±64.9mm3vs1270.6mm3±131.6mm3、1398.5mm3±193.0mm3;648.0mm3±65.9mm3vs1487.0mm3±243.0mm3、1660.0mm3±167.0mm3),差异均具有统计学意义(均P<0.01).Ad5-pCEA-Hsp70组动物外周血Hsp70蛋白及细胞因子INF-γ、TNF-α、IL-6的含量均显著高于Ad5-control组和PBS组(均P<0.01).HE染色发现,与Ad5-control组和PBS组相比,Ad5-pCEA-Hsp70组有较多的淋巴细胞浸润.经流式细胞仪检测,Ad5-pCEA-Hsp70组脾单核细胞中CD83+细胞比例显著高于Ad5-control组及PBS组(10.8±1.3%vs5.1±0.6%、4.8±0.6%;均P<0.01).脾淋巴细胞介导的CTL实验中,当效靶细胞比为1:1时,3组动物之间并无统计学差异(P>0.05),但随着效靶细胞比的增加,Ad5-pCEA-Hsp70组对胰腺癌细胞的杀伤能力较Ad5-control组和PBS组明显增加(P<0.05,P<0.01).结论:重组腺病毒Ad5-pCEA-Hsp70介导的Hsp70基因表达对大鼠胰腺癌动物模型的肿瘤生长具有抑制作用,其机制与促进树突状细胞(dendritic cells,DC)的成熟、诱导细胞因子INF-γ、TNF-α、IL-6的分泌、促进淋巴细胞浸润有关.     

血管生成抑制剂TNP-47O与细胞毒药物Gemcitabine的抗胰腺癌生长和转移作用的比较研究

目的　探讨血管生成抑制剂 (TNP- 4 70 )和细胞毒药物 (Gemcitabine)对胰腺癌裸鼠原位移植模型 (SOI)生长、转移的抑制作用及其作用机制。方法　把胰腺癌细胞株 SW1990皮下种植生长的癌组织移植于裸鼠胰腺尾部 ,制备胰腺癌 SOI模型 ;2 4只 SOI模型随机分为 TNP组 (TNP- 4 70 30 m g/ kg,皮下注射 ,隔日一次 ,疗程 8周 )、GEM组 (Gemcitabine 10 0 mg/ kg,腹腔内注射 ,术后第 0、3、6、9天给药 )和对照组 ,术后第 10周处死裸鼠。结果　 Gemcitabine侧重于抗胰腺癌生长 ,TNP- 4 70则侧重抑制胰腺癌转移 ,两者均无显著的预后改善作用 ;TNP组的微血管密度 (MVD)显著低于 GEM组和对照组 ,GEM组的肿瘤增殖指数 (PI)显著低于 TNP组和对照组 (均 P<0 .0 5 )。结论　血管生成抑制剂和细胞毒药物在抗肿瘤生长和转移的侧重点和作用机制方面均存在显著差异。     

Indomethacin suppresses growth of colon cancer via inhibition of angiogenesis in vivo

AIM: It has been reported that regular consumption of nonsteroidal anti-inflammatory drugs like indomethacin decreases the incidence and mortality rate of a number of gastrointestinal cancers. We aimed to explore the efficacy and possible mechanisms of indomethacin on tumor growth and tumor angiogenesis of human colon cancer xenografts in nude mice. METHODS: MTT (thiazolyl blue) assay was used to assess the effect of indomethacin on cultured human colorectal cancer cell line HCT116. HCT116 cells were inoculated subcutaneously into BALB/c-nu/nu mice. After oral administration of indomethacin, 3 mg/kg·d for 4 wk, animals were sacrificed by cervical dislocation. Immunohistochemical staining was employed to determine the microvessel density (MVD) and vascular endothelial growth factor (VEGF) expression in tumor tissues. RESULTS: Indomethacin, a non-selective COX inhibitor, significantly decreased the viability of HCT116 cells in a dose-dependent manner (P<0.05) with 50% inhibition at approximately 318.2±12.7 μmol/L Growth of HCT116 cell tumor was significantly suppressed by indomethacin. The tumor volume was significantly decreased in the treated group (458.89±32.07 mm3) compared to the control group (828.21±31.59 mm3) (P<0.05). The MVD of the treated group (19.50±5.32) was markedly decreased compared to the control group (37.40±4.93) (P<0.001). The VEGF expression of the treated group (1.19±0.17) was obviously reduced as compared to the control group (1.90±0.48) (P<0.01). The decrease in MVD was positively correlated with the decrease of VEGF expression (rs = 0.714, P<0.05). We did not see gastrointestinal complications in the treated group and no differences were noted in the body weight of the mice between the two groups throughout the study CONCLUSION: Indomethacin can significantly decrease the viability of cultured HCT116 cells and retard human colorectal HCT116 cell tumor growth via inhibiting tumor angiogenesis, which might be through reduction of VEGF expression.     

Anti-tumor activities and apoptosis-regulated mechanisms of bufalin on the orthotopic transplantation tumor model of human hepatocellular carcinoma in nude mice

AIM： To investigate anti-tumor activities and apoptosisregulated mechanisms of bufalin in the orthotopic transplantation tumor model of human hepatocellular carcinoma in nude mice.
METHODS： BEL-7402 cells of human hepatocellular carcinoma were inoculated to form subcutaneous tumors, and were implanted into the liver to establish orthotopic transplantation tumor models of human hepatocellular carcinoma in nude mice. Seventy-five animals were randomized divided into five groups （n = 15）. Bufalin was injected intraperitoneally into three groups at doses of 1.5 mg/kg （BF1）, 1 mg/kg （BF2） and 0.5 mg/kg （BF3） for d 15-24, respectively. The NS group was injected an equal volume of saline as above and adriamycin was injected intraperitoneally into the ADM group at a dose of 8.0 mg/kg for d 15. Ten mice in each group were killed at d 25 and the survival time in each group was calculated. We also observed the morphologic alterations in the myocardium, brain, liver, kidney and tumor tissues by pathology and electron microscopy, measured the apoptotic rate by TUNEL staining method, and detected the expression of apoptosis-regulated genes bcl-2 and bax by immunohistochemical staining and RT-PCR in tumor tissues.
RESULTS： The tumor volumes in each group of bufalin were reduced significantly （35.21±12.51 vs 170.39 ± 25.29; 49.83 ± 11.46 vs 170.39 ± 25.29; 83.99 ± 24.63 vs 170.39 ± 25.29, P 〈 0.01, respectively）, and the survival times were prolonged in group BF1-2 （31.8 ± 4.2 vs 23.4 ± 2.1 and 29.4 ± 3.4 vs 23.4 ± 2.1, P 〈 0.05, respectively）, and necrosis was mainly in severe or moderate degree in group BF1-2. No morphological changes were detected in the myocardium, brain, liver and kidney tissues. Apoptotic characteristics could be seen in group BF1-2. The positive rates of bcl-2 and bax protein expression of each group by immunohistochemical staining were 10.0%, 10.0%, 20.0%, 10.0% and 20.0%; 90.0%, 80.0%, 80.0%, 40.0% and 30.0%, respectively. Loss of expression of bcl-2 mRNA     

Efficacy of a novel histone deacetylase inhibitor in murine models of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a leading cause of cancer death worldwide, yet effective therapeutic options for advanced HCC are limited. This study was aimed at assessing the antitumor effect of a novel phenylbutyrate-derived histone deacetylase (HDAC) inhibitor, OSU-HDAC42, vis-à-vis suberoylanilide hydroxamic acid (SAHA), in in vitro and in vivo models of human HCC. OSU-HDAC42 was several times more potent than SAHA in suppressing the viability of PLC5, Huh7, and Hep3B cells with submicromolar median inhibitory concentration (IC(50)) values. With respect to SAHA, OSU-HDAC42 exhibited greater apoptogenic potency, which was associated with reduced levels of the apoptotic regulators phosphorylated Akt B-cell lymphoma-xL, survivin, cellular inhibitor of apoptosis protein 1, and cellular inhibitor of apoptosis protein 2. The in vivo efficacy of OSU-HDAC42 versus SAHA was assessed in orthotopic and subcutaneous xenograft tumor models in athymic nude mice. Daily oral treatments with OSU-HDAC42 and SAHA, both at 25 mg/kg, suppressed the growth of orthotopic PLC5 tumor xenografts by 91% and 66%, respectively, and of established subcutaneous PLC5 tumor xenografts by 85% and 56%, respectively. This differential tumor suppression correlated with the modulation of intratumoral biomarkers associated with HDAC inhibition and apoptosis regulation. Moreover, the oral administration of OSU-HDAC42 at 50 mg/kg every other day markedly suppressed ectopic tumor growth in mice bearing large tumor burdens (500 mm(3)) at the start of treatment. CONCLUSION: OSU-HDAC42 is a potent, orally bioavailable inhibitor of HDAC with a broad spectrum of antitumor activity that includes targets regulating multiple aspects of cancer cell survival. These results suggest that OSU-HDAC42 has clinical value in therapeutic strategies for HCC.     

Synergetic anticancer effect of combined gemcitabine and photodynamic therapy on pancreatic cancer in vivo

AIM： To investigate the anti-tumor effects of combined cytotoxic drug （gemcitabine） and photodynamic therapy （PDT） on human pancreatic cancer xenograft in nude mice.
METHODS： Human pancreatic cancer cell line SW1990 was used in the investigation of the in vivo effect of combined gemcitabine and PDT on human pancreatic cancer xenograft in mice. Sixty mice were randomly allocated into a control group （without treatment）, photosensitizer treatment group （2 mg/kg photosan, without illumination）, chemotherapy group （50 mg/kg gemcitabine i.p.）, PDT group （2 mg/kg photosan ＋ laser irradiation） and combined treatment group （photosan ＋ chemotherapy）, with 12 mice in each group. Tumor size was measured twice every week. Anti-tumor activity in different groups was evaluated by tumor growth inhibition （TGI）
RESULTS： No significant anti-tumor effect was observed either in photosensitizer treatment group or in chemotherapy group. PDT led to necrosis in cancer lesions and significantly reduced tumor volume compared with photosensitizer on day 6 and at the following time points after initialization of therapy （0.24 ± 0.15-0.49 ± 0.08 vs 0.43 ± 0.18-1.25± 0.09, P 〈 0.05）. PDT significantly reduced tumor volume in combined treatment group compared with photosensitizer treatment group （0.12 ± 0.07-0.28 ± 0.22 vs 0.39 ± 0.15-2.20 ± 0.12, P 〈 0.05）, small dose chemotherapy group （0.12 ± 0.07-0.28 ± 0.12 vs 0.32 ± 0.14-1.16 ± 0.08, P 〈 0.05） and control group （0.12 ± 0.07-0.28 ± 0.12 vs 0.43 ± 0.18-1.25 ± 0.09, P 〈 0.05）. TGI was higher in the combined treatment group （82.42%） than in the PDT group （58.18%）.
CONCLUSION： PDT has a significant anti-tumor effect, which is maintained for a short time and can be significantly enhanced by small doses of gemcitabine.     

Inhibition of angiogenesis and HCT-116 xenograft tumor growth in mice by kallistatin

AIM: To investigate the inhibitory effect of kallistatin (KAL) on angiogenesis and HCT-116 xenograft tumor growth. METHODS: Heterotopic tumors were induced by subcutaneous injection of 2 × 106 HCT-11 cells in mice. Seven days later, 2 × 1011 rAAV-GFP or rAAV-KAL was injected intratumorally (n = 5 for each group). The mice were sacrificed at d 28, by which time the tumors in the rAAV-GFP group had grown to beyond 5% of the total body weight. Tumor growth was measured by calipers in two dimensions. Tumor angiogenesis was determined with tumor microvessel density (MVD) by immunohistology. Tumor cell proliferation was assessed by Ki-67 staining. RESULTS: Intratumor injection of rAAV-KAL inhibited tumor growth in the treatment group by 78% (171 ± 52 mm3) at d 21 after virus infection compared to the control group (776 ± 241 mm3). Microvessel density was significantly inhibited in tumor tissues treated with rAAV-KAL. rAAV-KAL also decreased the proportion of proliferating cells (Ki-67 positive cells) in tumors compared with the control group.CONCLUSION: rAAV-mediated expression of KAL inhibits the growth of colon cancer by reducing angiogenesis and proliferation of tumor cells, and may provide a promising anti-angiogenesis-based approach to the treatment of metastatic colorectal cancer.     

Establishment of an orthotopic pancreatic cancer mouse model: Cells suspended and injected in Matrigel

AIM: To establish an orthotopic mouse model of pancreatic cancer that mimics the pathological features of exocrine pancreatic adenocarcinoma.METHODS: Pan02 cells were suspended in low-temperature Matrigel and injected into the parenchyma of pancreatic tails of C57BL/6 mice, with cells suspended in phosphate buffered saline (PBS) serving as a control. Primary and implanted tumors were confirmed pathologically. The rate of tumor formation and intraperitoneal implantation in the two groups were compared at different time points after injection. Leakage and intra-abdominal dispersion of Matrigel and PBS, both dyed with methylene blue, were compared after injection into the parenchyma of the pancreas. We observed adherence and proliferation in Pan02 cells suspended in Matrigel in vitro. We also compared the pathological manifestation of this orthotopic pancreatic cancer model in the head and tails of the pancreas. The characteristics of the origin of epithelial cells and exocrine markers of established orthotopic pancreatic tumors were confirmed using immunohistochemistry.RESULTS: Diluted Matrigel could form a gel drip in the pancreatic parenchyma, effectively preventing leakage from the injection site and avoiding dispersion in the abdominal cavity. Pan02 cells were able to adhere to a dish, proliferate, and migrate in the gel drip. The tumor formation rate in the Matrigel group was 100% at both 2 and 3 wk after injection, whereas it was 25.0% and 37.5% in the PBS group at 2 and 3 wk, respectively (P < 0.05). The intraperitoneal tumor implantation rate was 75.0% in the PBS group after 3 wk of injection, while it was 12.5% in the Matrigel group (P < 0.05). Hepatoduodenal ligament and duodenal invasions with obstructive jaundice and upper digestive obstruction with mesenteric lymph node metastasis were observed in the pancreatic head group. In the pancreatic tail group, spleen and gastric invasion were dominant, leading to retroperitoneal lymph nodes metastasis. Positive immunohistochemical staining of cytokeratin and negative staining of vimentin and chromogranin A confirmed that the orthotopic pancreatic tumor injected with Pan02 cells suspended in Matrigel was of epithelial origin and expressed exocrine markers of cancer.CONCLUSION: This method of low-temperature Matrigel suspension and injection is effective for establishing an orthotopic mouse model of pancreatic cancer.     

肝癌细胞不同制悬方法建立裸鼠移植瘤模型的比较

目的比较肝癌细胞不同制悬方法建立裸鼠皮下瘤及原位瘤模型,优选建模方法。方法将肝癌细胞分别采用PBS缓冲液(PBS组)、无血清DMEM溶液(DMEM组)和含10%血清的DMEM溶液(血清DMEM组)3种液体制悬后注入裸鼠皮下建立肝癌裸鼠皮下瘤模型,比较皮下瘤的体积、瘤重及成瘤率;将肝癌细胞分别采用PBS缓冲液(PBS组)、无血清DMEM溶液(DMEM组)和含10%血清的DMEM溶液(血清DMEM组)3种液体制悬后注入裸鼠肝脏建立肝癌裸鼠原位瘤模型,比较原位瘤的成瘤率。结果3组裸鼠皮下瘤模型的皮下瘤体积及瘤重相比,差异无统计学意义(P0.05),但是PBS组及DMEM组的成瘤率(90%和100%)明显高于血清DMEM组(40%),差异有统计学意义(P0.05);裸鼠原位瘤模型中PBS组的成瘤率(90%)明显高于DMEM组(40%)及血清DMEM组(20%),差异有统计学意义(P0.05)。结论采用PBS缓冲液或无血清DMEM溶液对肝癌细胞稀释制悬可以有效建立裸鼠皮下瘤模型,采用PBS缓冲液对肝癌细胞稀释制悬可以有效建立裸鼠原位瘤模型。     

Expansion of endothelial surface by an increase of vessel diameter during tumor angiogenesis in experimental and hepatocellular and pancreatic cancer

AIM: A low vessel density is a common feature of malignant tumors. We suggested that the expansion of vessel diameter might reconstitute the oxygen and nutritient‘s supply in this situation. The aim of the present study was to compare the number and diameter of blood vessels in pancreatic and liver carcinoma with normal tissue.METHODS: Tumor induction of pancreatic (DSL6A) or hepatocellular (Morris-hepatoma) carcinoma was performed in male Lewis (pancreatic cancer) and ACI (hepatoma) rats by an orthotopic inoculation of solid tumor fragments (pancreatic cancer) or tumor cells (hepatoma). Six weeks (pancreatic cancer) or 12 d (hepatoma) after tumor implantation, the tumor microvasculature as well as normal pancreatic or liver blood vessels were investigated by intravital microscopy. The number of perfused blood vessels in tumor and healthy tissue was assessed by computer-assisted image analysis.RESULTS: The vessel density in healthy pancreas (565&#177;89n/mm^2) was significantly higher compared to pancreatic cancer (116&#177;36 n/mm^2) (P&lt;0.001). Healthy liver showed also a significantly higher vessel density (689+36 n/ram2) compared to liver carcinoma (286+32 n/mm2) (P&lt;0.01). The comparison of diameter frequency showed a significant increase of vessel diameter in both malignant tumors compared to normal tissue (P&lt;0.05).CONCLUSION: The expansion of endothelial cells during tumor angiogenesis is accompanied to a large extent by an increase of vessel diameter rather than by formation of new blood vessels. This may be a possible adaptive mechanism by which experimental pancreatic and hepatocellular cancers expand their endothelial diffusion surface of endothelium to compensate for inadequate neoangiogenesis.     

Suppression of human colon tumor growth by adenoviral vector-mediated NK4 expression in an athymic mouse model

AIM： To investigate the suppressive effects of adenoviral vector-mediated expression of NK4, an antagonist of hepatocyte growth factor （HGF）, on human colon cancer in an athymic mouse model to explore the possibility of applying NK4 to cancer gene therapy. METHODS： A human colon tumor model was developed by subcutaneous implantation of tumor tissue formed by LS174T cells grown in athymic mice. Fifteen tumorbearing mice were randomized into three groups （n= 5 in each group） at d 3 after tumor implantation and mice were injected intratumorally with phosphate-buffered saline （PBS） or with recombinant adenovirus expressing 13-galactosidase （Ad-LacZ） or NK4 （rvAdCMV/NK4） at a 6-d interval for total 5 injections in each mouse. Tumor sizes were measured during treatment to draw a tumor growth curve. At d 26 after the first treatment, all animals were sacrificed and the tumors were removed to immunohistochemically examine proliferating cell nuclear antigen （PCNA）, microvessel density （represented by CD31）, and apoptotic cells. In a separate experiment, 15 additional athymic mice were employed to develop a tumor metastasis model by intraperitoneal injection （ip） of LS174T cells. These mice were randomized into 3 groups （n = 5 in each group） at d 1 after injection and were treated by ip injection of PBS, or Ad-LacZ, or rvAdCMV/NK4 at a 6-d interval for total two injections in each mouse. All animals were sacrificed at d 14 and the numbers and weights of disseminated tumors within the abdominal cavity were measured. RESULTS： Growth of significantly suppressed human colon tumors were in the athymic mice treatedwith rvAdCMV/NK4 （2537.4± 892.3 mm^3） compared to those treated by either PBS （5175.2 ± 1228.6 mm^3） or Ad-LacZ （5578.8± 1955.7 mm^3） （P 〈 0.05）. The tumor growth inhibition rate was as high as 51%. Immunohistochemical staining revealed a similar PCNA labeling index （75.1% ± 11.2% in PBS group vs 72.8% ± 7.6% in Ad-LacZ group vs 69.3% ± 9.4% in rvAdCMV