The suppression of colon cancer cell growth in nude mice by targeting beta-catenin/TCF pathway

The adenomatous polyposis coli (APC) or beta-catenin genes are frequently mutated in colorectal cancers, leading to activation of downstream genes with beta-catenin/T-cell factor (Tcf)-responsive promoters. We have developed a gene therapy approach selectively targeting colorectal cancer cells in which beta-catenin/Tcf4 pathway is activated by using a recombinant adenovirus AdTOP-CMV-TK, which carries a herpes simplex virus thymidine kinase gene (HSV TK) under the control of a beta-catenin/Tcf-response promoter linking to a minimum CMV promoter. AdTOP-CMV-TK and ganciclovir (GCV) treatment significantly suppressed the growth of human DLD-1 colon cancer cells in nude mice. Furthermore, no significant tumor suppression effect was observed in human hepatoma cell line SK-HEP-1, in which the beta-catenin/Tcf pathway is not activated, as a control experiment. In summary, we demonstrated the selective targeting of colorectal cancers with activated beta-catenin by AdTOP-CMV-TK and GCV treatment in animal models, as well as its therapeutic potential for colon cancer metastasized to liver.     

白桦脂酸对人类大肠癌细胞裸鼠体内生长及血管生成的抑制作用(英文)

Objective:Angiogenesis plays a major role in the pathogenesis of many disorders.Vascular endothelial growth factor(VEGF) has been shown to be the key regulator of normal and pathological angiogenesis.Many studies showed that decreased expression of VEGF has been inhibited growth and migration of cancer cells.The aim of this study was to explore the effects of Betulinic acid on the VEGF expression and the growth of colorectal cell SW480 xenografts in nude mice.Methods:The xenografts derived from colorectal c...     

Epidermal growth factor suppresses the tumor growth of human breast cancer transplanted in nude mice

The present work was performed in order to clarify the effects of epidermal growth factor (EGF) and transforming growth factor-beta (TGF-beta) on the tumor growth of human breast cancer transplanted in nude mice. A local injection of 2 micrograms EGF significantly suppressed the tumor growth of human breast cancer MX-1 and primary breast tumor (UM-1) which was first isolated from a human female breast cancer patient in our laboratory. On the other hand, TGF-beta did not suppress the growth of those tumors. Our result indicates that human EGF may be useful as a therapeutic agent for some human breast cancers. Human EGF may lead to a new trend of therapy in the treatment of cancer.     

塞来昔布抑制人类三阴性乳腺癌裸鼠移植瘤生长的实验研究

 【摘要】　目的　探讨塞来昔布（celecoxib）对人类三阴性乳腺癌（TNBC）肿瘤生长及细胞凋亡的影响。方法　32只裸鼠于背部皮下接种人类TNBC细胞株MDA-MB-231,随机分为空白对照组及低、中、高剂量塞来昔布组（25、50、100 mg?kg-1?d-1）。实验结束后,留取移植瘤标本,观察用药前后裸鼠肿瘤体积的变化;流式细胞术（FCM）检测肿瘤细胞凋亡率;免疫组织化学法检测NF-κB p65和p50分子的表达;Western blot法检测凋亡相关分子Caspase-3、Survivin蛋白的表达。结果　塞来昔布治疗组肿瘤体积较对照组均明显减小。中、高剂量塞来昔布治疗组凋亡率分别为（13.58±3.16）％、（21.91±4.75）％,与对照组的（3.15±1.73）％相比差异有统计学意义（t＝6.736,12.151,均P＜0.05）,塞来昔布低、中、高剂量组p65表达阳性率分别为79.3 %、46.7 %、23.9 %,与对照组（89.7 %）相比差异有统计学意义（χ2＝3.312,10.785,15.900,均P＜0.05）。Western blot结果显示,塞来昔布治疗后肿瘤组织中Caspase-3蛋白出现了裂解片段,并且随药物浓度增加,裂解片段表达量逐渐增加。Survivin蛋白随药物浓度增加表达逐渐下调。结论　塞来昔布可以诱导TNBC裸鼠移植瘤细胞凋亡,抑制肿瘤生长,其抗肿瘤作用机制可能部分与抑制p65分子以及下调Survivin蛋白表达有关。     

Role of polyamines in the growth of hormone-responsive and -resistant human breast cancer cells in nude mice.

Recent in vitro data suggest that at least some hormone-independent breast cancer cells exhibit increased polyamine biosynthesis and resistance to antipolyamine therapy. To address this issue under conditions of in vivo growth, we tested the antiproliferative effect of the polyamine synthetic inhibitor alpha-difluoromethyl-ornithine (DFMO) on hormone-dependent (MCF-7) and -independent (MDA-MB-231, BT-20) breast cancer cell lines growing in nude mice. We observed that DFMO significantly inhibited the growth of established tumors to a similar extent in all cell lines, even though tumor regression was only observed with MCF-7 cells. DFMO, while inhibiting E2-supported MCF-7 breast cancer growth, did not inhibit E2-stimulated progesterone receptor synthesis. Cellular levels of polyamines were highest in MCF-7 cells and lowest in the BT-20 cell line. Tumor content of spermidine was similarly suppressed by DFMO treatment in the 3 cell lines, while the spermine level was unaffected. Cellular putrescine levels were suppressed in MCF-7 and BT-20 cells. Administration of DFMO prior to implantation of fragments of MCF-7 or MDA-MB-231 tumors in nude mice significantly inhibited tumor development to a similar extent. The action of DFMO seemed to be predominantly tumoristatic since new tumors develop in some mice upon discontinuation of the drug. We conclude that the hormone-independent breast cancer cell lines tested do not exhibit increased polyamine biosynthesis or resistance to antipolyamine therapy when grown in vivo in nude mice.     

Sodium phenylacetate enhances the inhibitory effect of dextran derivative on breast cancer cell growth in vitro and in nude mice

Sodium phenylacetate (NaPa) and carboxymethyl benzylamide dextran derivative (CMDB(LS4)) are able to inhibit growth of breast tumour cells. In this study, we explored whether the combination of NaPa and CMDB(LS4)may enhance their respective inhibitory effects on the MCF-7ras cell growth in vitro and in vivo. NaPa inhibited MCF-7ras cell proliferation by reducing the DNA replication concomitantly with a recruitment of cells in G0/G1 phase and by inducing apoptosis in a dose- and time-dependent manner. The addition of CMDB(LS4)potentiated the NaPa antiproliferative effect in the manner dependent on the ratio of CMDB(LS4)and NaPa concentrations. In nude mice, CMDB(LS4)(150 mg kg(-1)) or NaPa (40 mg kg(-1)) administrated twice a week, for 7 weeks inhibited MCF-7ras xenograft growth by 40% and 60%, respectively. The treatment by both, CMDB(LS4)and NaPa, decreased tumour growth by 83% without any toxicity. To better understand the mechanism of NaPa and CMDB(LS4)action we assessed their effect on mitogenic activity of MCF-7ras conditioned medium (CM) on BALBC/3T3 fibroblasts. CMDB(LS4)added to the CM, inhibited its mitogenic activity whereas NaPa had an anti-mitogenic effect when CM was prepared from MCF-7ras cells pretreated with NaPa. Thus, the antiproliferative effects of NaPa and CMDB(LS4)involve 2 different mechanisms explaining, at least in part, the possible synergism between them. Overall, this study points to the potential use of a combination of dextran derivatives with NaPa to inhibit the breast tumour growth.     

赖氨酰氧化酶表达干扰对乳腺癌裸鼠移植瘤生长影响及机制研究

目的:探讨抑制乳腺癌细胞MD-MB-231中赖氨酰氧化酶(lysyl oxidase,LOX)的表达对乳腺癌裸鼠移植瘤生长的影响及可能机制。方法:设计合成特异性LOX基因慢病毒干扰载体(LOX-RNAi-LV)转染乳腺癌细胞MDA-MB-231,采用荧光定量PCR和蛋白质印迹法检测LOX mRNA和蛋白的表达;建立乳腺癌裸鼠原位移植模型,观察移植瘤的生长情况。采用免疫组化方法检测移植瘤组织中LOX蛋白及肿瘤增殖、转移相关蛋白Ki-67、MMP-2、MMP-9和HIF-1α的表达。结果:转染LOX-RNAi-LV的人乳腺癌细胞MDA-MB-231中LOX mRNA和蛋白的相对表达量分别为0.102±0.083和0.156±0.004,与空白对照组(0.945±0.158和0.916±0.007)相比,表达率均明显下调,抑制率分别为89.2%和83.0%。裸鼠原位接种癌细胞后6d均有肿瘤生成,40d后接种转染LOX-RNAi-LV的MDA-MB-231细胞的裸鼠移植瘤体积为(108.89±26.61)mm3,质量为(0.117±0.021)g;均明显低于空白对照组(400.15±79.81)mm3,(0.433±0.068)g,以及阴性对照组(380.15±65.81)mm3,(0.404±0.053)g,差异有统计学意义,P值均为0.000。移植瘤组织中LOX、Ki-67、MMP-2、MMP-9和HIF-1α蛋白相对表达水平分别为0.198±0.036、0.347±0.054、0.379±0.048、0.335±0.067和0.307±0.073,较空白对照组和阴性对照组明显降低,P值均<0.01。结论:干扰MDA-MB-231中LOX的表达,可抑制乳腺癌裸鼠移植瘤的生长侵袭,LOX可能通过调节Ki-67、MMP-2、MMP-9和HIF-1α蛋白的表达,在乳腺癌的侵袭转移中发挥作用。     

Ellagic acid inhibits human pancreatic cancer growth in Balb c nude mice

Ellagic acid (EA) is a polyphenol found in several plants and fruits. The objectives of this study were to examine the molecular mechanisms by which EA inhibits pancreatic cancer growth in Balb C nude mice. PANC-1 cells were injected subcutaneously into Balb c nude mice, and tumor-bearing mice were treated with EA. The expression of Akt, Shh and Notch and their target gene products were measured by the immunohistochemistry and Western blot analysis. Treatment of PANC-1 xenografted mice with EA resulted in significant inhibition in tumor growth which was associated with suppression of cell proliferation and caspase-3 activation, and induction of PARP cleavage. EA inhibited the expression of Bcl-2, cyclin D1, CDK2, and CDK6, and induced the expression of Bax in tumor tissues compared to untreated control group. EA inhibited the markers of angiogenesis (COX-2, HIF1α, VEGF, VEGFR, IL-6 and IL-8), and metastasis (MMP-2 and MMP-9) in tumor tissues. Furthermore, treatment of mice with EA caused a significant inhibition in phospho-Akt, Gli1, Gli2, Notch1, Notch3, and Hey1. EA also reversed epithelial to mesenchymal transition by up-regulating E-cadherin and inhibiting the expression of Snail, MMP-2 and MMP-9. These data suggest that EA can inhibit pancreatic cancer growth, angiogenesis and metastasis by suppressing Akt, Shh and Notch pathways. In view of the fact that EA could effectively inhibit human pancreatic cancer growth by suppressing Akt, Shh and Notch pathways, our findings suggest that the use of EA would be beneficial for the management of pancreatic cancer.     

缺氧对乳腺癌和宫颈癌裸鼠移植瘤EGFR表达及细胞凋亡的影响

目的 在乳腺癌、宫颈癌裸鼠成瘤模型中观察缺氧对表皮生长因子受体(EGFR)表达和细胞凋亡的影响。方法 以人乳腺癌MCF-7和宫颈癌HeLa移植裸鼠模型为研究对象,利用激光共聚焦显微镜观察缺氧区程度和EGFR表达情况;利用TUNEL染色观察EGFR表达对缺氧肿瘤细胞凋亡的影响。结果 在乳腺癌MCF-7和宫颈癌HeLa细胞缺氧程度高的区域,EGFR高表达和低表达均存在。此外,与EGFR的低表达肿瘤组织相比,凋亡程度在EGFR高表达肿瘤组织中降低。结论 乳腺癌、宫颈癌细胞缺氧对EGFR表达呈非均一性作用,缺氧诱导EGFR表达与细胞凋亡呈负相关。     

Inhibition of platelet-derived growth factor receptor signaling restricts the growth of human breast cancer in the bone of nude mice.

PURPOSE: Bone is a common site for breast cancer metastasis. Platelet-derived growth factor (PDGF) and PDGF receptors (PDGFR) are involved in the regulation of bone resorption. This study examined the effects of STI571 (imatinib mesylate), which inhibits PDGFR tyrosine kinase signaling, on the growth of human breast cancer cells in the bone of nude mice with consequent osteolysis. EXPERIMENTAL DESIGN: Human breast cancer MDA-MB-435 cells were injected into the tibia of female nude mice. Two weeks later the mice were treated with p.o. and injected water (control), daily p.o. STI571, weekly injection of paclitaxel, or daily STI571, plus weekly paclitaxel, for up to 8 weeks. Growth of tumors in bones and osteolysis were monitored by digital radiography and tumors were collected for histochemical analysis. RESULTS: Mice treated with STI571 or STI571 plus paclitaxel had smaller bone tumors with less lytic bone destruction than did mice treated with water or paclitaxel alone. The results of treatment with paclitaxel plus STI571 did not differ from those with STI571 alone. Immunohistochemistry showed that PDGF-A, PDGF-B, PDGFRalpha, and PDGFRbeta were expressed in the bone tumors. STI571 treatment inhibited PDGFR phosphorylation in tumor cells and tumor-associated endothelial cells, coincident with increased apoptosis, reduced proliferation, and lower microvessel density in the tumors. CONCLUSIONS: Activated PDGFRs are expressed by endothelial and tumor cells in breast cancer tumors growing in the bone of nude mice. Interfering with PDGFR signaling may be an approach to control the progressive growth of breast cancer cells and thus reduce bone lysis.     

Conjugated docosahexaenoic acid suppresses KPL-1 human breast cancer cell growth in vitro and in vivo: potential mechanisms of action

Introduction

The present study was conducted to examine the effect of conjugated docosahexaenoic acid (CDHA) on cell growth, cell cycle progression, mode of cell death, and expression of cell cycle regulatory and/or apoptosis-related proteins in KPL-1 human breast cancer cell line. This effect of CDHA was compared with that of docosahexaenoic acid (DHA).

Methods

KPL-1 cell growth was assessed by colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay; cell cycle progression and mode of cell death were examined by flow cytometry; and levels of expression of p53, p21^Cip1/Waf1, cyclin D₁, Bax, and Bcl-2 proteins were examined by Western blotting analysis. In vivo tumor growth was examined by injecting KPL-1 cells subcutaneously into the area of the right thoracic mammary fat pad of female athymic mice fed a CDHA diet.

Results

CDHA inhibited KPL-1 cells more effectively than did DHA (50% inhibitory concentration for 72 hours: 97 μmol/l and 270 μmol/l, respectively). With both CDHA and DHA growth inhibition was due to apoptosis, as indicated by the appearance of a sub-G₁ fraction. The apoptosis cascade involved downregulation of Bcl-2 protein; Bax expression was unchanged. Cell cycle progression was due to G₀/G₁ arrest, which involved increased expression of p53 and p21^Cip1/Waf1, and decreased expression of cyclin D₁. CDHA modulated cell cycle regulatory proteins and apoptosis-related proteins in a manner similar to that of parent DHA. In the athymic mouse system 1.0% dietary CDHA, but not 0.2%, significantly suppressed growth of KPL-1 tumor cells; CDHA tended to decrease regional lymph node metastasis in a dose dependent manner.

Conclusion

CDHA inhibited growth of KPL-1 human breast cancer cells in vitro more effectively than did DHA. The mechanisms of action involved modulation of apoptosis cascade and cell cycle progression. Dietary CDHA at 1.0% suppressed KPL-1 cell growth in the athymic mouse system.     

Effect of dietary fat on human breast cancer growth and lung metastasis in nude mice

Results from epidemiological studies have generally indicated an association of dietary saturated animal fats with human breast cancer risk. Some studies, however, have suggested a similar association for some polyunsaturated vegetable fats shown to promote both rodent mammary carcinogenesis and metastasis. This study was performed to evaluate the effects of corn oil on growth and metastasis of MDA-MB-435 human breast cancer cells, which have a propensity for metastasis. Corn oil is rich in the omega-6 fatty acid linoleic acid. Fifty-eight female athymic nude mice (NCr-nu/nu) were fed a high-fat diet (23% wt/wt corn oil; 12% linoleic acid) or a low-fat diet (5% wt/wt corn oil; 2.7% linoleic acid). Seven days after diets were started, tumor cells (1 x 10(6) were injected into a mammary fat pad. The time to appearance of solid tumors and the tumor size were recorded. After 15 weeks, the study was terminated, and autopsies were performed to determine the weight of the primary tumor and the extent of metastasis. The latent interval for tumor appearance in the animals fed the high-fat diet was shorter than that in the low-fat diet group, and the tumor growth rate in the high-fat diet group showed a small but statistically significant increase compared with the low-fat diet group. Primary tumors developed in 27 of the 29 mice on the high-fat diet and in 21 of the 29 on the low-fat diet. Of the mice with palpable primary tumors, 18 of 27 in the high-fat diet group and eight of 21 in the low-fat diet group had macroscopic lung metastases. The extent of metastasis in the high-fat diet group was independent of the primary tumor weight, but only those in the low-fat diet group with primary tumors weighing more than 2 g developed metastases. These results suggest that a high-fat diet rich in omega-6 polyunsaturated fatty acid can enhance metastasis of human breast cancer cells in this mouse model. The findings support the need for further study of the relationship between dietary polyunsaturated fats and breast cancer risk and for experiments to determine the effect on metastasis of only a 50% difference in fat intake--the dietary goal of the proposed clinical trials of low-fat dietary intervention in breast cancer patients.     

Modulation of cell cycle regulatory protein expression and suppression of tumor growth by mimosine in nude mice

Our previous results demonstrated that the plant amino acid mimosine blocked cell cycle progression and suppressed proliferation of human lung cancer cells in vitro by multiple mechanisms. Inhibition of cyclin D1 expression or induction of cyclin-dependent kinase inhibitor p21WAF1 expression was found in mimosine-treated lung cancer cells. However, whether mimosine may modulate the expression of these cell cycle regulatory proteins and suppress tumor growth in vivo is unknown. In this study, we examined the anti-cancer effect of mimosine on human H226 lung cancer cells grown in nude mice. Our results demonstrated that mimosine inhibits cyclin D1 and induces p21WAF1 expression in vivo. Furthermore, results of TUNEL analysis indicated that mimosine may induce apoptosis to suppress tumor growth in nude mice. Collectively, these results suggest that mimosine exerts anti-cancer effect in vivo and might be useful in the therapy of lung cancer.     

PAMAM-NK4纳米复合物对乳腺癌裸鼠移植瘤生长的抑制作用

目的:探讨新型纳米材料聚酰胺-胺型树枝状高聚合物(polyamidoamine dendrimer,PAMAM)介导NK4基因对乳腺癌MDA-MB-231、MCF-7细胞生长的抑制作用及对MDA-MB-231细胞移植瘤裸鼠模型的治疗作用.方法:制备PAMAM-NK4纳米复合物颗粒,纳米复合物和空载体PAMAM分别转染MDA-MB-231和MCF-7细胞作为实验组和对照组.MTT实验、West-ern blotting和流式细胞术分别检测转染PAMAM-NK4对细胞增殖、NK4蛋白表达和细胞凋亡的影响.40只雌性裸鼠经皮下注射建立MDA-MB-231细胞移植瘤裸鼠模型,随机分成4组,每组10只裸鼠:空白组肿瘤接种部位旁皮下注射0.2 ml 0.9％NaCl溶液、空载体组注射0.2ml含100μg PAMAM-LacZ质粒的溶液、给药组注射0.2 ml含100 μg PAMAM-NK4质粒的溶液、阳性对照组腹腔注射0.2 ml多柔比星(100 μg)溶液.连续注射7d,第30天处死裸鼠,完整摘除肿瘤,测量肿瘤体积和质量.Western blotting检测各组移植瘤组织NK4蛋白表达.结果:PAMAM-NK4纳米粒转染MDA-MB-231、MCF-7细胞后能够稳定表达NK4蛋白、抑制细胞增殖和增加细胞凋亡率.成功建立MDA-MB-231细胞移植瘤裸鼠模型,给药组和阳性对照组肿瘤体积及质量显著低于空白组(P＜0.05),且安全性良好;给药组NK4蛋白表达显著高于空白组(P＜0.05).结论:PAMAM-NK4纳米粒对乳腺癌MDA-MB-231、MCF-7细胞生长具有抑制作用,并对人乳腺癌细胞移植瘤裸鼠模型具有治疗作用.     

泌乳素诱导蛋白表达下调对三阴性乳腺癌细胞裸鼠体内成瘤影响研究

目的：探讨泌乳素诱导蛋白（prolactininducibleprotein,PIP）表达下调对三阴性乳腺癌（triplenegativebreastcancer,TNBC）MDA-MB453细胞在裸鼠体内成瘤的影响。方法：采用脂质体将PIPsiRNA转染至乳腺癌MDA_MB453细胞,蛋白质印迹法检测PIP的表达下调情况。采用4周龄BALB／c雌性裸鼠,建立乳腺癌MDA-MB-453细胞裸鼠皮下种植瘤模型,瘤内注射siRNA-脂质体混悬液,观察PIPsiRNA对肿瘤生长的影响。采用免疫组织化学法检测肿瘤组织中CyclinDl和VEGF的表达情况。结果：PIP表达下调后,其在裸鼠体内成瘤能力明显降低,肿瘤平均体积空白对照组为（1075±65）mm2,阴性对照组为（1095±72）mm2,实验组为（473±56）mm2,空白对照组与阴性对照组差异无统计学意义,P=0．719,空白对照组与实验组、实验组与阴性对照组差异均有统计学意义,P〈0．001。空白对照组肿瘤平均体质量为（908士86）mg,阴性对照组为（889±64）mg,实验组为（272±30）mg,空白对照组与阴性对照组差异无统计学意义,P=0．738,空白对照组与实验组、实验组与阴性对照组差异均有统计学意义,P〈0．001。肿瘤生长抑制率为71．1％。免疫组化结果显示,PIP表达下调的肿瘤组织中CyclinD1的相对表达量空白对照组为1535±78,阴性对照组为1594±123,实验组为367±72,空白对照组与阴性对照组差异无统计学意义,P=0．472,空白对照与实验组、实验组与阴性对照组差异均有统计学意义,P〈O．001。VEGF的相对表达量空白对照组为4270±558,阴性对照组为4365±324,实验组为1286±292,空白对照组与阴性对照组差异无统计学意义,P=0．758,空白对照与实验组、实验组与阴性对照组差异均有统计学意义,P〈0．001。结论：下调PIP基因表达可明显抑制乳腺癌MDA-MB-453细胞体内成瘤能力,提示PIP可能在乳腺癌发生和发展中发挥重要作用。     

CXCR4单克隆抗体抑制乳腺癌MCF-7细胞裸鼠移植瘤的实验研究

目的 研究CXC趋化因子受体4(CXC chemokine receptor 4,CXCR4)单克隆抗体(CXCR4 mAb)对人乳腺癌MCF-7细胞裸鼠皮下移植瘤生长的影响,并初步探讨CXCR4 mAb抗肿瘤的作用机制.方法 采用8周龄Balb/c雌性裸鼠,建立乳腺癌MCF-7细胞裸鼠皮下移植瘤模型.运用CXCR4 mAb进行干预,从整体水平观察CXCR4 mAb对肿瘤生长的影响,采用免疫组织化学法检测肿瘤组织中增殖细胞核抗原(PCNA)、半胱氨酸天冬氨酸酶3(Caspase-3)和血管内皮细胞生长因子(VEGF)的表达情况.结果 CXCR4 mAb可明显抑制移植瘤的生长,瘤体抑制率达到71.4%;CXCR4 mAb治疗后的肿瘤组织中PCNA和VEGF表达明显下降,而Caspase-3表达上升.结论 CXCR4 mAb可能是通过抑制肿瘤细胞增殖、促进肿瘤细胞凋亡及抑制肿瘤血管形成而发挥抗肿瘤生长的作用.     

CXCR4单克隆抗体抑制乳腺癌MCF-7细胞裸鼠移植瘤的实验研究

目的：研究CXC趋化因子受体4（CXC chemokine receptor 4,CXCR4）单克隆抗体（CXCR4 mAb）对人乳腺癌MCF-7细胞裸鼠皮下移植瘤生长的影响,并初步探讨CXCR4 mAb抗肿瘤的作用机制。方法：采用8周龄Balb/c雌性裸鼠,建立乳腺癌MCF-7细胞裸鼠皮下移植瘤模型。运用CXCR4 mAb进行干预,从整体水平观察CXCR4 mAb对肿瘤生长的影响,采用免疫组织化学法检测肿瘤组织中增殖细胞核抗原（PCNA）、半胱氨酸天冬氨酸酶3（Caspase-3）和血管内皮细胞生长因子（VEGF）的表达情况。结果：CXCR4 mAb可明显抑制移植瘤的生长,瘤体抑制率达到71.4%;CXCR4 mAb治疗后的肿瘤组织中PCNA和VEGF表达明显下降,而Caspase-3表达上升。结论：CXCR4 mAb可能是通过抑制肿瘤细胞增殖、促进肿瘤细胞凋亡及抑制肿瘤血管形成而发挥抗肿瘤生长的作用。     

Effect of estrogens and antiestrogens on growth of human breast cancer cells in athymic nude mice

Endocrine therapy with estrogen deprivation or with antiestrogens results in tumor regression in a subset of patients with advanced breast cancer. To better understand the mechanisms by which estrogens and antiestrogens modulate breast cancer growth in vivo, we have studied the effects of endocrine manipulation on the development and growth of tumors derived from cultured human breast cancer cells in the athymic nude mouse. MCF-7 breast cancer cells were inoculated into 6-week-old female BALB/c athymic nude mice. Tumor growth did not occur in ovariectomized mice. Cells remained viable, however, since estrogen supplementation more than 30 days later resulted in tumor formation. Minimal tumor growth was observed in intact female nude mice which have low circulating estrogen levels. Tumor development and growth in ovariectomized or intact mice supplemented with 17 beta-estradiol in the form of a s.c. pellet were dose dependent; growth rates increased with estrogen doses ranging from 0.01 to 0.5 mg. Antiestrogen treatment with either tamoxifen or LY156758 caused transient stimulation of tumor growth, followed by a prolonged stationary phase. Growth resumed with estrogen supplementation. Treatment of mice bearing established MCF-7 tumors with estrogen withdrawal (removal of estrogen pellet) resulted in cessation of tumor growth, but not in tumor regression. Growth inhibition was also observed with antiestrogens and was dose dependent. However, tumor regression did not occur, even in mice treated with high doses of tamoxifen (serum concentration of 1.0 microM) for as long as 60 days. Tumor growth was restored in these mice with estrogen replenishment. Tumor cells also remained viable histologically despite prolonged (1 month) estrogen deprivation or antiestrogen therapy, although the mitotic index was markedly reduced. Similar observations were made with mice inoculated with the hormone-responsive ZR75-1 human breast cancer cells, but not with hormone-independent MDA-231 cells which were not influenced by estrogen or antiestrogen treatment. In summary, development and growth of MCF-7 and ZR75-1 tumors in nude mice are estrogen dependent. Endocrine therapy by estrogen deprivation or antiestrogen treatment inhibits tumor cell proliferation in nude mice, but does not cause tumor regression or loss of cell viability.     

HOXA13 在非小细胞肺癌组织中的表达及其对A549 细胞和移植瘤生长的影响

[摘要] 目的：探讨HOXA13 在非小细胞肺癌（non-small cell lung cancer,NSCLC）组织中的表达及沉默HOXA13 基因表达对A549 细胞和移植瘤生长的影响。方法：收集2014 年3 月至2016 年4 月在焦作煤业集团有限责任公司中央医院胸外科接受手术切除治疗的112 例NSCLC癌组织和相对应的癌旁组织。qPCR实验检测NSCLC癌和癌旁组织中HOXA13 表达。培养A549 细胞并分为siRNA-HOXA13 组、阴性对照组和对照组,qPCR实验检测A549 细胞中HOXA13 表达,CCK-8 法检测细胞增殖能力,Transwell法检测细胞侵袭能力。建立裸鼠移植瘤模型,观察裸鼠生长情况,5 周后处死,称瘤体质量并计算抑瘤率;qPCR实验检测瘤体组织中HOXA13 表达水平。结果：NSCLC 癌组织中HOXA13 mRNA相对表达量明显高于癌旁组织（1.83±0.13 vs 1.12±0.10,t=47.008,P=0.000）,其相对表达量与TNM 分期、分化程度和淋巴结转移相关（P<0.05）。siRNA-HOXA13 组细胞中HOXA13 mRNA相对表达量低于阴性对照组和对照组（均P<0.05）;siRNA-HOXA13 组24、48、72、96 h 时细胞增殖水平（D值）明显低于阴性对照组和对照组（F=30.727、5.427、13.816 和24.454,均P<0.05 或P<0.01）;siRNA-HOXA13 组侵袭细胞数低于阴性对照组和对照组（均P<0.05）;siRNA-HOXA13 组裸鼠移植瘤5 周时瘤体质量小于阴性对照组和对照组,而抑瘤率高于阴性对照组（均P<0.05）;siRNA-HOXA13 组裸鼠移植瘤组织中HOXA13 mRNA相对表达量低于阴性对照组和对照组（均P<0.01）。结论：NSCLC癌组织中HOXA13 呈高表达,且与肿瘤发生、进展及转移有关;特异性沉默HOXA13 基因表达可抑制细胞增殖和侵袭力,并抑制裸鼠移植瘤生长。