Recombinant Human Endostatin Endostar Inhibits Tumor Growth and Metastasis in a Mouse Xenograft Model of Colon Cancer

To investigate the effects of recombinant human endostatin Endostar on metastasis and angiogenesis and lymphangiogenesis of colorectal cancer cells in a mouse xenograft model. Colon cancer cells SW620 were injected subcutaneously into the left hind flank of nude mice to establish mouse xenograft models. The mice were treated with normal saline or Endostar subcutaneously every other day. The growth and lymph node metastasis of tumor cells, angiogenesis and lymphangiogenesis in tumor tissue were detected. Apoptosis and cell cycle distribution were studied by flow cytometry. The expression of VEGF-A, -C, or -D in SW620 cells was determined by immunoblotting assays. Endostar inhibited tumor growth and the rate of lymph node metastasis (P < 0.01). The density of blood vessels in or around the tumor area was 12.27 ± 1.21 and 22.25 ± 2.69 per field in Endostar-treated mice and controls (P < 0.05), respectively. Endostar also decreased the density of lymphatic vessels in tumor tissues (7.84 ± 0.81 vs. 13.83 ± 1.08, P < 0.05). Endostar suppresses angiogenesis and lymphangiogenesis in the lymph nodes with metastases, simultaneously. The expression of VEGF-A, -C and -D in SW620 cells treated with Endostar was substantially lower than that of controls. Endostar inhibited growth and lymph node metastasis of colon cancer cells by inhibiting angiogenesis and lymphangiogenesis in a mouse xenograft model of colon cancer.     

NG-Nitro-L-arginine Methyl Ester Inhibits Bone Metastasis after Modified Intracardiac Injection of Human Breast Cancer Cells in a Nude Mouse Model

We investigated the effects of N^G-nitro-L-arginine-methyI ester (L-NAME), a nitric oxide synthase (NOS) inhibitor, on hone metastasis of human breast cancer, MDA-231 cells. Tumor cells (2 × 10⁵ cells in 0.2 ml of phosphate-buffered saline; PBS) were injected through the diaphragm into the left ventricle of the heart of laparotomized nude mice (male 5-week-old ICR- nu/nu ). L-NAME (2 mg/ mouse/injection in 0.1 ml of PBS) was given intraperitoneally to mice 6 h and 3 h before and immediately, 3 h, 6 h, 18 h and 21 h after the intraeardlac injection of tumor cells. As a control, 0.1 ml of PBS was injected instead of L-NAME. The effect of N^G-nitro-D-arginine-methyl ester CD-NAME; 2 mg/mouse/injection), an inactive analogue of L-NAME, was also investigated to evaluate the specificity of L-NAME action. Radiographical examination 31 days after the tumor-cell injection showed that the incidence and number of osteolytic bone metastases and the number of bones with metastasis in L-NAME-treated mice were significantly reduced compared with those in PBS-treated mice (P<0,05). The differences between PBS-treated and D-NAME-treated mice were not significant. Our findings suggest that specific and appropriate NOS inhibitors may represent a new pharmacological approach to therapy for cancer patients at risk of developing osteolytic bone metastases.     

Sabutoclax, a Mcl-1 Antagonist, Inhibits Tumorigenesis in Transgenic Mouse and Human Xenograft Models of Prostate Cancer

Resistance to available therapeutic agents has been a common problem thwarting progress in treatment of castrate-resistant and metastatic prostate cancer (PCa). Overexpression of the Bcl-2 family members, including Mcl-1, in PCa cells is known to inhibit intracellular mitochondrial-dependent apoptosis. Here we report the development of a novel transgenic mouse model that spontaneously develops prostatic intraepithelial neoplasia and adenocarcinoma by the inducible, conditional knockout of transforming growth factor β receptor type II in stromal fibroblastic cells (Tgfbr2^ColTKO). The Tgfbr2^ColTKO prostate epithelia demonstrated down-regulation of luminal and basal differentiation markers, as well as Pten expression and up-regulation of Mcl-1. However, unlike in men, Tgfbr2^ColTKO prostates exhibited no regression acutely after castration. The administration of Sabutoclax (BI-97C1), a pan-active Bcl-2 protein family antagonist mediated apoptosis in castrate-resistant PCa cells of Tgfbr2^ColTKO mice and human subcutaneous, orthotopic, and intratibial xenograft PCa models. Interestingly, Sabutoclax had little apoptotic effect on benign prostate tissue in Tgfbr2^ColTKO and wild-type mice. Sabutoclax was able to block c-Met activation, a critical axis in PCa metastatic progression. Further, Sabutoclax synergistically sensitized PC-3 cells to the cytotoxic effects of docetaxel (Taxotere). Together, these data suggest that Sabutoclax inhibits castrate-resistant PCa alone at the primary and bone metastatic site as well as support sensitivity to docetaxel treatment.     

Dual Targeting of the Akt/mTOR Signaling Pathway Inhibits Castration-Resistant Prostate Cancer in a Genetically Engineered Mouse Model

Although the prognosis for clinically localized prostate cancer is now favorable, there are still no curative treatments for castration-resistant prostate cancer (CRPC) and, therefore, it remains fatal. In this study, we investigate a new therapeutic approach for treatment of CRPC, which involves dual targeting of a major signaling pathway that is frequently deregulated in the disease. We found that dual targeting of the Akt and mTOR signaling pathways with their respective inhibitors, MK-2206 and ridaforolimus (MK-8669), is highly effective for inhibiting CRPC in preclinical studies in vivo using a refined genetically engineered mouse model of the disease. The efficacy of the combination treatment contrasts with their limited efficacy as single agents, since delivery of MK-2206 or MK-8669 individually had a modest impact in vivo on the overall tumor phenotype. In human prostate cancer cell lines, although not in the mouse model, the synergistic actions of MK-2206 and ridaforolimus (MK-8669) are due in part to limiting the mTORC2 feedback activation of Akt. Moreover, the effects of these drugs are mediated by inhibition of cellular proliferation via the retinoblastoma (Rb) pathway. Our findings suggest that dual targeting of the Akt and mTOR signaling pathways using MK-2206 and ridaforolimus (MK-8669) may be effective for treatment of CRPC, particularly for patients with deregulated Rb pathway activity. Cancer Res; 72(17); 4483-93. ?2012 AACR.     

Nab-paclitaxel Efficacy in the Orthotopic Model of Human Breast Cancer Is Significantly Enhanced By Concurrent Anti-Vascular Endothelial Growth Factor A Therapy

Nab-paclitaxel is an albumin-bound 130-nm particle form of paclitaxel that has shown an improved efficacy in experimental tumor models and clinical studies compared with solvent-based paclitaxel. Anti-vascular endothelial growth factor A (VEGF-A) antibody bevacizumab is known to enhance antitumor activity of cytotoxic drugs. This study evaluated the effects of combined nab-paclitaxel and bevacizumab therapy on growth and metastatic spread of orthotopic breast tumors. Cytotoxic and clonogenic assays measured VEGF-A-dependent modulation of nabpaclitaxel toxicity on cultured tumor cells. Antitumor effects were assessed in mice with luciferase-tagged, wellestablished MDA-MB-231 tumors (250–310 mm³) treated with one, two, or three cycles of nab-paclitaxel (10 mg/kg, daily for five consecutive days), bevacizumab (2–8 mg/kg, twice a week), or with combination of both drugs. VEGF-A protected MDA-MB-231 cells against nab-paclitaxel cytotoxicity, whereas bevacizumab sensitized cells to the effect of the drug. Combined bevacizumab and nab-paclitaxel treatment synergistically inhibited tumor growth and metastasis resulting in up to 40% of complete regressions of well-established tumors. This therapy also decreased the incidence of lymphatic and pulmonary metastases by 60% and 100%, respectively. The significant increase in the cure of tumor-bearing mice in the nab-paclitaxel/bevacizumab combined group compared with mice treated with single drugs strongly advocates for implementing such strategy in clinics.     

A New Human Osteosarcoma Strain (Os-Beppu) with a High Rate of Pulmonary Metastasis in Nude Mice

A new human osteosarcoma strain (Os-Beppu) transplantable innude mice has been established. A high frequency of metastasis(87.2%) to the lung was observed throughout nine passages. Histologicallythe subcutaneous tumor and the metastatic lesions in nude micewere similar to the original human tumor, and osteoid and osteoclastformation were preserved. Osteoblasts were strongly positivefor alkaline phosphatase, while osteoclasts were positive foracid phosphatase. Karyotype analysis revealed human chromosomeswith a modal chromosome number of 41 (63.3%) and two markerchromosomes.     

蟾毒灵对裸鼠大肠癌原位移植瘤的抗肿瘤作用及其对凋亡相关基因Bcl-xL、Bax表达的影响

目的探讨蟾毒灵对裸鼠大肠癌原位移植瘤的抗肿瘤作用及其可能诱导凋亡的机制。方法将60只人结肠癌细胞株HCT-116建立的裸鼠原位移植瘤模型随机分为生理盐水（NS）组、5-Fu组、蟾毒灵低（BL）、中(BM)、高(BH)5组,每组12只,腹腔注射给药持续7d。用药结束后第24天每组分别处死6只裸鼠,完整取出肿瘤,测量肿瘤大小,计算肿瘤抑制率;剩余裸鼠观察带瘤生存期;TUNEL法检测原位移植瘤细胞的凋亡指数;实时荧光定量PCR法和Western blot法检测凋亡相关基因Bcl-x_L、Bax mRNA和蛋白的表达。结果5-Fu组、BL组、BM组、BH组的肿瘤抑制率分别为69.6%、45.6%、56.2%、58.5%,肿瘤体积与NS组比较明显缩小（P＜0.01);BL组、BM组带瘤生存期与NS组相比较明显延长(P< 0.05)。TUNEL结果显示蟾毒灵用药组的凋亡指数明显高于NS组(P＜0.01）;荧光定量PCR和Western结果显示蟾毒灵可抑制Bcl-x_L基因表达,促进Bax基因表达（P＜0.05）。结论蟾毒灵对裸鼠大肠癌原位移植瘤有显著的抗肿瘤作用,能够抑制Bcl-xL基因和促进Bax基因表达,诱导肿瘤细胞凋亡可能是蟾毒灵抗肿瘤的重要机制之一。     

表皮生长因子受体及其靶向治疗在乳腺癌研究中的进展

表皮生长因子受体（EGFR）在人类多种恶性实体肿瘤中存在过表达或突变,并通过介导多种途径的信号通路调控细胞的生长、分化、增殖、黏附、迁移和存活等,常与预后不良、转移快、短期复发、生存期短等相关。全文简单介绍了EGFR的结构和功能特点,并对近年来EGFR与乳腺癌发生发展的关系及其靶向治疗等方面的研究现状进行综述,为以EGFR为靶点的乳腺癌治疗研究提供参考。     

Asparagus Polysaccharide and Gum with Hepatic Artery Embolization Induces Tumor Growth and Inhibits Angiogenesis in an Orthotopic Hepatocellular Carcinoma Model

Liver cancer is one of leading digestive malignancies with high morbidity and mortality. There is anurgent need for the development of novel therapies for this deadly disease. It has been proven that asparaguspolysaccharide, one of the most active derivates from the traditional medicine asparagus, possesses notableantitumor properties. However, little is known about the efficacy of asparagus polysaccharide as an adjuvantfor liver cancer chemotherapy. Herein, we reported that asparagus polysaccharide and its embolic agent form,asparagus gum, significantly inhibited liver tumor growth with transcatheter arterial chemoembolization (TACE)therapy in an orthotopic hepatocellular carcinoma (HCC) tumor model, while significantly inhibiting angiogenesisand promoting tumor cell apoptosis. Moreover, asparagine gelatinous possessed immunomodulatory functionsand showed little toxicity to the host. These results highlight the chemotherapeutic potential of asparaguspolysaccharide and warrant a future focus on development as novel chemotherapeutic agent for liver cancerTACE therapy.     

Changes in Serum and Tissue Carcinoembryonic Antigen with Growth of a Human Gastric Cancer Xenograft in Nude Mice

We established a human gastric cancer xenograft which, when inoculated into nude mice, showed a positive correlation between tumor growth and the serum level of carcinoembryonic antigen (CEA). Serum CEA levels in the mice rose continuously with increasing tumor weight after inoculation, showing a correlation coefficient of 0.96. A positive correlation was also observed between the tissue CEA level and tumor weight, the former increasing along with the latter. Furthermore, the level of serum CEA closely paralleled that of tissue CEA. The serum CEA level fell after tumor extirpation, with a half-life of approximately 86 h. These results suggest that the elevation of serum CEA is attributable to the gain in tumor weight as well as the increase of CEA production in the tumor tissue. Thus, human gastric cancer xenografts in nude mice are a good model for examining the biological role of CEA.     

Suppression of Prostate Cancer Growth by Resveratrol in The Transgenic Rat for Adenocarcinoma of Prostate (TRAP) Model.

Research into actions of resveratrol, abundantly present in red grape skin, has been greatly stimulated by its reported beneficial health influence. Since it was recently proposed as a potential prostate cancer chemopreventive agent, we here performed an in vivo experiment to explore its effect in the Transgenic Rat for Adenocarcinoma of Prostate (TRAP) model, featuring the rat probasin promoter/SV 40 T antigen. Resveratrol suppressed prostate cancer growth and induction of apoptosis through androgen receptor (AR) down-regulation, without any sign of toxicity. Resveratrol not only downregulated androgen receptor (AR) expression but also suppressed the androgen responsive glandular kallikrein 11 (Gk11), known to be an ortholog of the human prostate specific antigen (PSA), at the mRNA level. The data provide a mechanistic basis for resveratrol chemopreventive efficacy against prostate cancer.     

新型阿霉素前体药PDOX对人胃癌原位移植瘤模型的分子靶向治疗研究

  目的   比较PDOX与DOX对裸鼠人胃癌原位移植瘤模型的疗效和毒副作用。   方法  建立MGC-803人胃癌原位移植瘤模型35只, 随机分为PDOX组(n=12)、DOX组(n=12)和Control组(n=11), 接种后第10、17、24天按体质量给药, 每周进行两次详细全面记录。末次给药后1周终止实验, 取血行常规、生化检查; 解剖裸鼠, 详细记录胃部肿瘤及腹腔播散情况, 对肿瘤进行称重, 计算抑瘤率; 进行组织病理学检查, 分析肿瘤细胞增殖、凋亡, 肿瘤血管生成、侵袭转移等指标, 行统计学分析。   结果  至研究终点时,Control组和PDOX组全部存活,DOX组6只死亡。在肿瘤局部控制指标中,PDOX组和DOX组的胃肿瘤质量、体积均显著低于Control组（P<0.05）,PDOX组和DOX组抑瘤率分别为26.4%和24.9%,两组疗效相当（P>0.05）。在血常规指标中,PDOX组血小板计数高于Control组（P<0.05）,淋巴细胞比例低于Control组（P<0.05）,而红细胞计数和血红蛋白在三组间差异无统计学意义（P>0.05）。在心功能指标中,PDOX组CK-MB水平高于Control组（P<0.01）。CK、LDH、肝功能及肾功能指标三组间差异均无统计学意义（P>0.05）。PDOX组和DOX组淋巴管癌栓发生率显著低于Control组（P<0.05）。免疫组织化学结果显示PDOX组Ki-67水平显著低于DOX与Control组,三组间两两比较差异均有统计学意义（P<0.01）;Bcl-2、Bcl-6、Tunel、VEGF差异均无统计学意义（P>0.05）,CD34、D2-40有明显下降趋势。   结论  PDOX治疗人胃癌原位移植瘤模型的整体疗效优于DOX, 毒副作用低于DOX。      

Effect of Combination Therapy with Matrix Metalloproteinase Inhibitor MMI-166 and Mitomycin C on the Growth and Liver Metastasis of Human Colon Cancer

Several synthetic inhibitors of matrix metalloproteinases (MMPs) show antitumor, antimetastasis and antiangiogenesis effects in various models. Synergistic effects of combinations with conventional cytotoxic agents were reported previously. In this study, we examined the effects of a new selective MMP inhibitor, MMI-166, on tumor growth, angiogenesis and metastasis in a liver meta-static model of human xenotransplanted colon cancer (TK-4). We also investigated the synergistic effects of MMI-166 and a conventional cytotoxic agent, mitomycin C (MMC), in this model. Mice transplanted orthotopically with TK-4 were divided into 4 groups; a control group (treated with vehicle solution), an MMI-166 group in which MMI-166 was orally administered (p.o.) at a dose of 200 mg/kg, 6 days/week for 5 weeks, an MMC group in which MMC was administered intraperitoneally (i.p.) at a dose of 2 mg/kg/week for 5 weeks, and a combination group (treated with MMI-166 and MMC). MMI-166 did not inhibit transplanted tumor growth, but significantly inhibited liver metastasis compared with the control group and MMC group ( P <0.01). Significant antitumor and antimetastatic effects of the combination therapy were demonstrated. The microvessel density (MVD) detected by immunohistochemical staining with ER-MP12 antibody tended to be lower in the MMI-166 and the combination groups. These results suggest that MMI-166 has potential antimetastatic ability and a synergistic effect with MMC.     

Inhibitory Effect of Orally Administered 5-Aminolevulinic Acid on Prostate Carcinogenesis in the FVB-Transgenic Adenocarcinoma of a Mouse Prostate (FVB-TRAMP) Model

Background: 5-aminolevulinic acid (5-ALA) is a constituent of mitochondrial electron carriers, heme and cytochrome c, which are crucial for aerobic energy metabolism and cell apoptosis. We investigated the chemopreventive efficacy of 5-ALA against prostate cancer using the FVB-transgenic adenocarcinoma of mouse prostate (FVB-TRAMP) model. Methods: Samples were collected from 24 FVB-TRAMP mice at 12 and 20 weeks of age (named the first and second sets, respectively). Sixteen mice (from the first set) were randomly allocated into 3 treatment groups: 1) control (no treatment), 2) low dose of 5-ALA (30 mg/kg/day), and 3) high dose of 5-ALA (300 mg/kg/day). Similarly, 8 mice were divided into 2 treatment groups: 1) control and 2) high dose of 5-ALA (300 mg/kg/day). 5-ALA was orally administered to mice before cancer onset, from 6 weeks of age. Results: In the control group, prostate cancer was pathologically detected in 33 and 50 % of mice at 12 and 20 weeks, respectively, while 25% of 12-week old mice in the low-dose group were affected and none of the high-dose group mice developed prostate cancer. Immunohistochemical analysis showed higher expression of cytochrome c oxidase subunit 4 (COX4) in the prostate gland of the high-dose group compared to the control (P = 0.018). Similarly, enzyme-linked immunosorbent assay using lysed prostate tissue revealed higher amounts of cytochrome c in the prostate of the high-dose group compared to the control (P = 0.021). Furthermore, western blot analysis showed higher level of cleaved caspase-3 in mice in the high-dose group diagnosed with high-grade prostatic intraepithelial neoplasia. Conclusion: Our results suggest that oral 5-ALA may support the functional expression of mitochondrial cytochrome c and COX4, leading to caspase 3-dependent apoptosis in carcinogenesis in FVB-TRAMP mice. Future clinical studies are warranted to confirm the chemopreventive value of 5-ALA in prostate carcinogenesis.     

重组人白细胞介素-6抑制BTT_(739)小鼠膀胱癌生长和转移的实验研究

 目的　探讨重组人白细胞介素 6对小鼠膀胱癌BTT739生长和转移的抑制作用。方法将BTT739肿瘤细胞接种于T739近交系小鼠皮下 ( 2 6× 10 5/小鼠 ) ,2 4只小鼠随机分成 3组 ,第 3天始分别给予对照组溶剂 ( 0 9NS) 0 3mL ,治疗组重组人白细胞介素 6( 4× 10 6IU kg) ,日 2次 ,腹腔注射 ,共 2 0天 ,阳性对照组MMC ( 1mg kg)日 1次 ,腹腔注射计 14天。第 2 5天测对照组和治疗组的皮下瘤重及肺转移率 ,分别进行t检验和 χ2 检验。结果　两组皮下瘤重分别为 11 4± 1 9g和 7 4± 0 8g ,重组人白细胞介素 6有明显抑制BTT739肿瘤生长作用 ,抑瘤率 35 1% (P<0 0 5) ,而对肺转移灶数目及转移灶大小的抑制率分别为 61 3%和 2 6 2 % (P值均 <0 0 5) ,有显著性差异。结论　重组人白细胞介素 6可明显抑制BTT739小鼠膀胱癌生长和转移。     

Suppression of Human Pancreatic Cancer Growth in BALB/c Nude Mice by Manumycin, a Farnesyl:protein Transferase Inhibitor

Activating mutations of Ki- ras have been detected in most human pancreatic adenocarcinomas. Since Ras protein requires farnesylation to function, we investigated the effects of manumycin, a potent farnesyl:protein transferase inhibitor, on the growth in nude mice of a human pancreatic cancer cell line, MIA PaCa-2, with a point mutation in the Ki- ras gene. Tumor-bearing mice received intraperitoneal injection of 1 or 5 mg/kg manumycin daily for 5 days, or 2 mg/kg manumycin daily for 2 weeks. Growth of inoculated tumors was significantly inhibited by the treatment. The treatment significantly (P<0.05) lowered the numbers of bromodeoxyuridine-incorporating tumor cells. Manumycin did not have apparent hepatotoxicity in vivo . Farnesyl:protein transferase inhibitors could offer a new approach for cancer chemotherapy.     

An Anti-Urokinase Plasminogen Activator Receptor Antibody (ATN-658) Blocks Prostate Cancer Invasion,Migration, Growth,and Experimental Skeletal Metastasis In Vitro and In Vivo

Urokinase plasminogen activator receptor (uPAR) is a multidomain protein that plays important roles in the growth, invasion, and metastasis of a number of cancers. In the present study, we examined the effects of administration of a monoclonal anti-uPAR antibody (ATN-658) on prostate cancer progression in vitro and in vivo. We examined the effect of treatment of ATN-658 on human prostate cancer cell invasion, migration, proliferation, and regulation of intracellular signaling pathways. For in vivo studies, PC-3 cells (1 x 10⁶) were inoculated into the right flank of male Balb C nu/nu mice through subcutaneous or through intratibial route (2 x 10⁵) of male Fox Chase severe combined immunodeficient mice to monitor the effect on tumor growth and skeletal metastasis. Treatment with ATN-658 resulted in a significant dose-dependent decrease in PC-3 cell invasion and migration without affecting cell doubling time. Western blot analysis showed that ATN-658 treatment decreased the phosphorylation of serine/threonine protein kinase B (AKT), mitogen-activated protein kinase (MAPK), and focal adhesion kinase (FAK) without affecting AKT, MAPK, and FAK total protein expression. In in vivo studies, ATN-658 caused a significant decrease in tumor volume and a marked reduction in skeletal lesions as determined by Faxitron x-ray and micro-computed tomography. Immunohistochemical analysis of subcutaneous and tibial tumors showed a marked decrease in the levels of expression of pAKT, pMAPK, and pFAK, consistent with the in vitro observations. Results from these studies provide compelling evidence for the continued development of ATN-658 as a potential therapeutic agent for the treatment of prostate and other cancers expressing uPAR.