贝伐单抗靶向治疗非小细胞肺癌研究热点

目前非小细胞肺癌的标准化疗为两药联合,三药联合化疗并没有增加疗效．化疗到达了平台期。由于VEGFR具有独特的抗拒血管生成和其他恶性转化过程,使其成为极具吸引力的生物治疗靶点。目前有许多关于抑制肺癌血管生成药物进行临床前期研究,美国FDA已经批准贝伐单抗进入临床使用,现将其研究进展综述如下。     

贝伐珠单抗联合化疗治疗非鳞状细胞非小细胞肺癌的疗效观察

目的：观察贝伐珠单抗联合化疗治疗非鳞状细胞非小细胞肺癌的疗效和安全性.方法：回顾性分析2010年7月-2011年12月解放军总医院经组织病理学证实的局部进展或复发转移的非鳞状细胞非小细胞肺癌患者接受贝伐珠单抗联合化疗方案治疗的临床资料.贝伐珠单抗7.5mg/kg,每3周1次,联合多西他赛、培美曲塞或吉西他滨±铂类化疗.化疗2周期后按实体肿瘤疗效评价标准（RECIST）评价疗效,按美国癌症研究所制定的常见毒性判定标准（NCI-CTC） 3.0版评价不良反应.结果：21例患者中无完全缓解病例,部分缓解4例,稳定13例,进展4例,客观缓解率19.0％（4/21）,疾病控制率81.0％（17/21）,中位无疾病进展时间为7.0月,中位生存时间为10.4月.与贝伐珠单抗相关的不良反应出血6例（28.6％）,高血压1例（4.8％）,主要为Ⅰ、Ⅱ度,Ⅲ、Ⅳ度少见.结论：贝伐珠单抗联合化疗治疗进展或复发的非鳞状细胞非小细胞肺癌疗效确切,耐受性好.     

贝伐单抗一线治疗非小细胞肺癌研究进展

贝伐单抗是一种重组人源化单克隆IgG1抗体,通过选择性结合人血管内皮生长因子（VEGF）来抑制其生物活性,具有较强的抗肿瘤血管新生作用,在晚期非鳞非小细胞肺癌Ⅱ～Ⅳ期临床研究中显示出了较好的抗肿瘤活性,具有很好的应用前景。     

贝伐珠单抗联合化疗治疗复治晚期非鳞非小细胞肺癌的疗效及安全性观察

目的 探讨贝伐珠单抗联合化疗治疗复治晚期非鳞非小细胞肺癌（NSCLC）的疗效及安全性。方法 收集本院2010年5月至2014年7月经病理证实符合入选标准的84例复治晚期NSCLC患者,接受贝伐珠单抗联合化疗方案治疗,化疗2个周期后按照实体瘤疗效评价标准（RECIST 1.0）评价疗效,按照美国国立癌症研究所制定的通用药物毒性标准3.0版评价不良反应,采用Kaplan-Meier法进行生存分析。结果 84例患者均可评价疗效且无CR病例,其中获PR 12例,SD 42例,PD 30例,有效率和疾病控制率分别为14.8%和64.8%;全组的中位无进展生存期和总生存期分别为3.8个月和8.8个月;不良反应主要为骨髓抑制、高血压、肝功能损害、皮疹等,以1、2级为主。结论 贝伐珠单抗联合化疗治疗晚期非鳞NSCLC的疗效好,不良反应轻,值得临床上推广。     

贝伐单抗联合化疗治疗晚期多程治疗失败后的非小细胞肺癌临床观察

背景与目的:晚期非小细胞肺癌(non-small cell lung cancer,NSCLC)患者多程治疗失败后,目前尚无标准的化疗方案。本研究旨在观察贝伐单抗联合化疗治疗晚期NSCLC多程治疗失败后的疗效和安全性。方法:2010年1月—2011年2月经病理证实符合入选标准的35例晚期NSCLC患者,接受贝伐单抗联合化疗方案治疗。化疗2个周期后按照实体瘤疗效评价标准(RECIST 1.0)评价疗效。按照美国国立癌症研究所制定的通用药物毒性标准3.0版评价不良反应。结果:35例患者中,30例完成2个周期以上的化疗,32例病例可评价疗效,总体PR 7例,SD 18例,PD 7例,RR为21.9%(7/32),DCR为78.1%(25/32);中位PFS为3个月,中位OS为8个月。与贝伐单抗相关的不良反应以高血压、蛋白尿和出血多见,其中多为Ⅰ、Ⅱ级,Ⅲ、Ⅳ级少见。结论:贝伐单抗联合化疗对晚期多程治疗失败后的NSCLC有一定的抗肿瘤活性和较高的疾病控制率,安全性较高,临床受益率高,是一种有临床应用前景的治疗方法。     

贝伐珠单抗在非小细胞肺癌中应用的研究现状

目前非小细胞肺癌化疗疗效已经达平台期,亟需寻找新的方法提高疗效。贝伐珠单抗是一种重组抗VEGF单克隆抗体,是首个证实与化疗联合可提高晚期NSCLC 患者生存的靶向治疗药物。近年来许多关于贝伐珠单抗在NSCLC 一线、二线、辅助、新辅助治疗、联合放化疗,安全性及预测标志物的临床研究,现将其研究现状做一综述。      

贝伐珠单抗联合化疗对复治晚期非鳞非小细胞肺癌患者的疗效及预后分析

  目的  探讨贝伐珠单抗联合化疗对复治晚期非鳞非小细胞肺癌（non-squamous non-small cell lung cancer,NSNSCLC）患者的疗效和安全性,分析影响预后的因素。  方法  回顾性分析2013年2月至2017年6月北京胸科医院收治的41例复治晚期NSN? SCLC患者的病例资料。其中腺癌38例,其他病理类型3例。19例患者为二线治疗,22例患者为二线以上治疗。表皮生长因子受体（epidermal growth factor receptor,EGFR）突变阳性18例,突变阴性23例。评价贝伐珠单抗联合化疗的疗效和安全性,对可能影响预后的因素进行单因素和多因素分析。  结果  所有患者均接受化疗联合贝伐珠单抗的治疗,化疗的平均周期数为3.1个,贝伐珠单抗治疗的平均周期数为5.0个。41例患者均可评价疗效。全组患者客观缓解率（objective response rate,ORR）为12.2%,疾病控制率（disease control rate,DCR）为82.9%。二线治疗与二线以上治疗的患者疗效接近,ORR分别为10.5%、13.6%（P=0.572）,DCR分别为89.5%和77.3%（P=0.271）,差异无统计学意义。中位无进展生存期（progression-free survival,PFS）和中位总生存期（overall survival,OS）分别为4.6个月（95%CI:3.619~5.581）、11.9个月（95%CI:9.797~14.003）。单因素分析提示EGFR突变、贝伐珠单抗治疗周期数 > 4个及女性患者获得更长的生存（χ2=19.673,P < 0.001;χ2=6.820,P=0.009;χ2=6.374,P=0.012）。多因素分析显示,EGFR突变状态、贝伐珠单抗治疗周期数为影响患者预后的独立危险因素（HR=0.129,P=0.001;HR=0.336,P=0.012）。常见的不良反应有骨髓抑制、出血、高血压、蛋白尿等,多数为1~2级。  结论  贝伐珠单抗联合化疗对复治晚期NSNSCLC患者疗效确切,不良反应可耐受,EGFR突变阳性、贝伐珠单抗使用4个周期以上的患者预后较好。      

贝伐单抗联合培美曲塞加顺铂化疗方案对非小细胞肺癌患者生存率的影响

目的 分析贝伐单抗联合培美曲塞加顺铂化疗方案对非小细胞肺癌患者生存率的影响.方法 将我院收治的42例非小细胞肺癌患者随机分为观察组和对照组各21例,观察组患者采用贝伐单抗联合培美曲塞加顺铂化疗方案,对照组患者给予培美曲塞加顺铂化疗方案,21天为1个周期,观察比较两组患者2个周期以上的的近期疗效、远期疗效以及不良反应.结果 观察组客观有效率(ORR)为52.38%,显著高于对照组的28.57%,观察组的疾病控制率(DCR)为71.42%,显著高于对照组的61.9%,两组比较差异有统计学意义;观察组1年、3年和5年的生存率均明显高于对照组,差异有统计学意义;观察组的无进展生存时间(pFS)和总生存时间(OS)均显著优于对照组,两组比较差异有统计学意义;两组的不良反应主要表现在骨髓抑制和胃肠道反应方面,具体表现在血小板减少、贫血、白细胞减少、恶心呕吐、高血压、蛋白尿和鼻出血、咳血等方面,及时给予对症治疗后患者能够继续接受化疗.两组不良反应比较,差异无统计学意义.结论 贝伐单抗联合培美曲塞加顺铂化疗方案对非小细胞肺癌患者的治疗,与培美曲塞加顺铂化疗方案相比,疗效更加显著,患者的生存时间和生存率更高,没有加重患者的不良反应,患者的耐受性比较好,值得临床推广使用.     

贝伐单抗与培美曲塞联合治疗晚期非小细胞肺癌的临床疗效及不良反应

目的 探讨贝伐单抗联合培美曲塞治疗晚期非小细胞肺癌的疗效以及不良反应.方法 收集200例晚期非小细胞肺癌患者作为研究对象,将200例患者随机分为对照组和治疗组,每组100例.对照组采用顺铂+培美曲塞化疗,治疗组在顺铂+培美曲塞的基础上加贝伐单抗,比较2组用药后的疗效及不良反应.结果 治疗组患者的ORR(CR+PR)和DCR(CR+PR+SD)分别为43%、85%,相比于对照组ORR和DCR的20%、69%,差异明显,具有统计学意义(P<0.05).对照组和治疗组的化疗过程中的不良反应如呕吐、血小板减少、中性粒细胞减少、肝肾功能异常无论在发生率还是在0~Ⅳ级分级上都没有明显差异,不具统计学意义(P>0.05).治疗组的血管内皮细胞生长因子A mRNA含量为(70.6±12.3)pg·mL-1、血管内皮细胞生长因子B mRNA含量为(67.4±11.3)pg·mL-1、血管内皮细胞生长因子C mRNA含量为(63.9±11.7)pg·mL-1,都明显低于对照组,差异具有统计学意义(P<0.05).结论 贝伐单抗联合培美曲塞及顺铂对晚期非小细胞肺癌的临床治疗效果理想,患者耐受性好,无明显的不良反应,且贝伐单抗对血管内皮细胞生长因子具有抑制作用,目前可以作为1种较为理想的晚期非小细胞肺癌的治疗方案.     

贝伐单抗治疗晚期非小细胞肺癌的疗效与安全性临床研究进展

抗血管生成治疗是肿瘤常见的治疗方式之一。贝伐单抗作为抗血管内皮生长因子的单克隆抗体,是目前唯一被批准用于晚期非小细胞肺癌（non-small cell lung cancer,NSCLC）一线治疗的抗血管生成制剂。为了扩大贝伐单抗用于晚期NSCLC的适应证,大量研究继续探索贝伐单抗在一线治疗的联合形式外,还致力于探索其在后线及跨线治疗的疗效和安全性。本文就近年来贝伐单抗用于晚期NSCLC治疗的疗效与安全性临床研究进展进行综述。      

Carboxymethyl benzylamide dextran inhibits angiogenesis and growth of VEGF-overexpressing human epidermoid carcinoma xenograft in nude mice

Vascular endothelial growth factor (VEGF) expression is elevated in a wide variety of solid tumours. Inhibition of VEGF activities is able to reduce angiogenesis and tumour growth. We have recently shown in vitro that carboxymethyl dextran benzylamide (CMDB7) prevents the binding of VEGF(165) to its cell surface receptors and thus inhibits VEGF activities on endothelial cells. In the present study, we explored the effects of CMDB7 on highly aggressive human epidermoid carcinoma A431 cells known to overexpress epidermal growth factor receptors (EGFRs) and produce a high amount of VEGF and a minor quantity of bFGF. In vitro, CMDB7 blocked the mitogenic activity of A431-conditioned medium on endothelial cells. Concerning A431 cells, CMDB7 inhibited their proliferation and the VEGF(165) binding to them. In vivo, administration of CMDB7 (10 mg kg(-1)) three times per week for 2 weeks inhibited the growth of A431 xenografts in nude mice by 73% as compared to the control group. Immunostaining of endothelial cells with mouse-specific GSL-1 lectin in tumour sections revealed that CMDB7 also inhibited the density of intratumour endothelial cells by 66%. These findings demonstrate that CMDB7 has an efficient antiangiogenic and antitumour action in vivo even when tumour cells produce a high level of VEGF and EGFRs.     

艾瑞昔布抑制肺腺癌A549细胞裸鼠移植瘤侵袭和转移及其机制

背景与目的：环氧化酶-2(cyclooxygenase-2,COX-2)与肺癌血管生成、淋巴转移相关,COX-2抑制剂能够抑制肺癌侵袭和转移。该研究探讨COX-2抑制剂艾瑞昔布能否抑制肺腺癌A549细胞裸鼠移植瘤侵袭和转移及其机制,以及与洛铂联合应用的疗效。方法：将肺腺癌A549细胞接种于30只BALB/c雄性裸鼠右侧腋部皮下,建立移植瘤模型。将造模成功裸鼠(n=29)随机分为4组：对照组(n=7)、艾瑞昔布组(n=8)、洛铂组(n=7)和艾瑞昔布联合洛铂组(n=7)。对照组灌胃等量灭菌蒸馏水及尾静脉注射等量0.9%NaCl溶液,治疗组分别给予灌胃艾瑞昔布片每日40 mg/kg及尾静脉注射洛铂每周7.5 mg/kg相应处理。每日观察裸鼠饮食、活动等一般情况。给药6周后处死裸鼠,剥取移植瘤组织。应用免疫组织化学法和real-time PCR分别检测各组肿瘤PTEN、cortactin蛋白及相应mRNA表达水平。采用单因素方差分析及非参数检验进行统计学分析。结果：最后1周发现所有裸鼠饮食、活动较之前减少,逐渐消瘦,洛铂组及联合组变化较明显。与对照组相比,艾瑞昔布组及联合组PTEN蛋白及其mRNA表达明显升高,差异有统计学意义(P均<0.001);与对照组相比,艾瑞昔布组及联合组cortactin蛋白及其mRNA表达明显降低,差异有统计学意义(P均<0.001)。PTEN与cortactin蛋白、PTEN mRNA与cortactin mRNA均呈显著负相关(r=-0.660、-0.983,P均<0.001)。结论：艾瑞昔布能够抑制非小细胞肺癌侵袭和转移,其作用机制可能与上调PTEN蛋白及下调cortactin蛋白表达有关。艾瑞昔布对洛铂化疗可能具有增敏作用。     

Lidamycin induces apoptosis of B-cell lymphoma cells and inhibits xenograft growth in nude mice

OBJECTIVE To study the cytotoxicity of Lidamycin （LDM） and its induction of apoptosis in Raji and Daudi cells of B-cell lymphoma, and the inhibition of growth of the lymphoma Raji xenograft in nude mice. METHODS MTT assay was used to observe the inhibition by LDM on the proliferation of the Raji and Daudi ceils. Annexin V-FITC/PI double-stain, in combination with flow cytometry （FCM）, was used to determine the induction of apoptosis by LDM in Raji cells. The B-cell lymphoma Raji xenograft model in nude mice was set up to detect the in vivo antitumor activity of LDM. RESULTS LDM markedly inhibited the proliferation of the Raji and Daudi cells in vitro, with IC50 values of 7.13×10^-11 mol/L and 2.91×10^-10 mol/L, respectively. The apoptotic rates of Raji cells were respectively 77.98% and 67.63% at 0.5 nmol/L and 0.25 nmol/L of LDM, indicating an obvious induction of apoptosis in Raji cells. LDM inhibited the formation and growth of human B-cell lymphoma Raji xenograft in nude mice. The inhibition rates of tumor growth were respectively 74.9% and 65.2% in LDM at dosage group of 0.05 mg/kg and 0.025 mg/kg, suggesting an apparent prolongation of survival time in the nude mouse bearing lymphoma. CONCLUSION LDM can effectively induce apoptosis of the B-cell lymphoma cells and inhibit the xenograft growth in nude mice.     

Pomegranate fruit extract inhibits prosurvival pathways in human A549 lung carcinoma cells and tumor growth in athymic nude mice

Developing novel mechanism-based chemopreventive approaches for lung cancer through the use of dietary substances which humans can accept has become an important goal. In the present study, employing normal human bronchial epithelial cells (NHBE) and human lung carcinoma A549 cells, we first compared the growth inhibitory effects of pomegranate fruit extract (PFE). Treatment of PFE (50-150 microg/ml) for 72 h was found to result in a decrease in the viability of A549 cells but had only minimal effects on NHBE cells as assessed by the MTT and Trypan blue assays. PFE treatment of A549 cells also resulted in dose-dependent arrest of cells in G0-G1 phase of the cell cycle (as assessed by DNA cell cycle analysis). We further found that PFE treatment also resulted in (i) induction of WAF1/p21 and KIP1/p27, (ii) decrease in the protein expressions of cyclins D1, D2 and E, and (iii) decrease in cyclin-dependent kinase (cdk) 2, cdk4 and cdk6 expression. The treatment of cells with PFE inhibited (i) phosphorylation of MAPK proteins, (ii) inhibition of PI3K, (iii) phosphorylation of Akt at Thr308, (iv) NF-kappaB and IKKalpha, (v) degradation and phosphorylation of IkappaBalpha, and (vi) Ki-67 and PCNA. We also found that PFE treatment to A549 cells resulted in inhibition of NF-kappaB DNA-binding activity. Oral administration of PFE (0.1 and 0.2%, wt/vol) to athymic nude mice implanted with A549 cells resulted in a significant inhibition in tumor growth. Our results provide a suggestion that PFE can be a useful chemopreventive/chemotherapeutic agent against human lung cancer.     

Epidermal growth factor receptor blockade by antibody IMC-C225 inhibits growth of a human pancreatic carcinoma xenograft in nude mice

BACKGROUND: Pancreatic carcinoma is associated with a poor prognosis, and treatment options for patients with this disease are limited. The epidermal growth factor (EGF) receptor and its ligands are overexpressed in human pancreatic carcinoma and may contribute to the pathophysiology of these tumors. METHODS: The anti-EGF receptor monoclonal antibody IMC-C225 was used to determine the effects of EGF receptor blockade on the growth of human pancreatic carcinoma BxPC-3 cells in vitro. Athymic mice bearing established (200 mm(3)) subcutaneous BxPC-3 xenografts were treated with IMC-C225 (17 or 33 mg/kg every 3 days) alone or in combination with 5-fluorouracil (17 mg/kg twice weekly). RESULTS: IMC-C225 inhibited exogenous ligand-stimulated tyrosine phosphorylation of the EGF receptor on BxPC-3 tumor cells. Treatment of BxPC-3 cells with IMC-C225 inhibited DNA synthesis (23.8%) and colony formation in soft agar (45.6%). IMC-C225 treatment significantly suppressed the growth of BxPC-3 tumors compared with treatment with vehicle alone (P = 0.003). Combination therapy with IMC-C225 and the chemotherapeutic agent 5-fluorouracil enhanced the antitumor effects compared with either agent alone and resulted in regression of pancreatic tumors in several animals. Histologic examination of pancreatic tumors from mice treated with IMC-C225 showed extensive tumor necrosis that coincided with a substantial decrease in tumor cell proliferation and an increase in tumor cell apoptosis. CONCLUSIONS: These data suggest that IMC-C225 affects the growth of pancreatic tumors by inhibiting EGF receptor-dependent proliferation and survival, and demonstrates the potential for therapeutic application of IMC-C225 antibody in the treatment of human pancreatic carcinoma.     

Adenovirus-mediated gene therapy with an antiangiogenic fragment of thrombospondin-1 inhibits human leukemia xenograft growth in nude mice

Recent investigations support the idea that angiogenesis is involved in the pathophysiology of leukemia. Within a given microenvironment, the angiogenic response is regulated by a delicate balance of angiogenesis inducers and inhibitors. Thrombospondin-1 (TSP-1) is a multifunctional extracellular glycoprotein showing angiostatic properties in multiple in vitro and in vivo assays. Interestingly, there is also proangiogenic domain in this complex molecule. Development of TSP-1 as an antiangiogenic drug has been hindered by multiplicity of its functional effects, difficulties in its production and its poor pharmacokinetics. The aim of the present study was to establish a recombinant adenovirus (ADV.TSP-1(f)) expressing antiangiogenic fragment of TSP-1 (TSP-1(f)), and to determine the feasibility for use of the adenovirally expressed TSP-1(f) in leukemia gene therapy. The results of this investigation showed that TSP-1(f) was expressed efficiently in adenovirus-transduced human myelogenous leukemia K562 cells. Compared to the controls, although there was almost no effect on proliferation of K562 cells in vitro, adenovirus-mediated TSP-1(f) transduction inhibited the growth of K562 xenografts dramatically. Furthermore, the microvessel density (MVD) was much lower in the ADV.TSP-1(f)-treated tumors compared to the controls. These data support the use of in vivo gene delivery approach to produce antiangiogenic fragment of TSP-1 for leukemia therapy.     

Inhibition of human gastric adenocarcinoma xenograft growth in nude mice by alpha-difluoromethylornithine

We studied the effect of inhibition of polyamine biosynthesis by alpha-difluoromethylornithine on the growth of a human gastric adenocarcinoma (CLEES) xenotransplanted in nude mice. CLEES is a well-differentiated gastric adenocarcinoma of the intestinal type. The doubling time has ranged from 7 to 10 days through 11 passages. Electron microscopic and immunohistochemical studies comparing the original tumor and xenotransplants showed similar structure and similar amounts of carcinoembryonic antigen. Polyamine biosynthesis is required for cell division. alpha-Difluoromethylornithine inhibits ornithine decarboxylase, the rate-limiting enzyme in polyamine biosynthesis. In this study, 48 athymic mice were used in two experiments. In the first experiment, two groups of 12 mice each were inoculated with CLEES tumor cells and received either tap water or a 3% alpha-difluoromethylornithine solution as drinking water. Tumor size was measured twice weekly. Tumor size was significantly decreased from controls by the fourth week of treatment and at all points of analysis thereafter for 7 wk. In the second experiment, alpha-difluoromethylornithine significantly reduced tumor concentrations of the polyamines putrescine and spermidine. In addition, the tumor content of DNA was significantly reduced in treated mice (0.64 +/- 0.16 mg) compared to controls (4.76 +/- 0.92 mg). Our data suggest that inhibition of polyamine biosynthesis may be a useful component of multidrug chemotherapy for human gastric adenocarcinoma. Establishment of tumor lines such as this gastric adenocarcinoma will facilitate further studies on the biological behavior of human gastric cancer and its response to chemotherapeutic manipulation in vivo.     

RNA干扰Bcl-2基因表达对人胆管癌细胞及胆囊癌细胞株裸鼠移植瘤生长的抑制

目的：探讨Bcl-2基因的小干扰RNA（siRNA）真核表达载体干扰Bcl-2基因表达对人胆管癌细胞QBC939、胆囊癌细胞GBC-SD裸鼠体内移植瘤生长的抑制作用。方法：分别制作人胆管癌细胞QBC939、胆囊癌细胞GBC-SD细胞株移植瘤模型,随机分为3组,pSilencerTM-EGFP sh515组（实验组）、pSilencerTM-EGFP shCon组（空载体阴性对照组）和对照组。实验组用Bcl-2基因的小干扰RNA（siRNA）真核表达载体多点注射于移植瘤周围,空载体阴性对照组用空载体多点注射于移植瘤周围,对照组不作处理,观察其生长情况,计算肿瘤生长体积、生长率。6周后,处死裸鼠,剥离瘤体组织进行称重,并采用免疫组化检测Bcl-2蛋白的表达。结果：成功建立裸鼠人胆管癌细胞QBC939,胆囊癌GBC-SD细胞的动物模型。胆管癌细胞实验组、空载体阴性对照组、对照组瘤体平均体积（mm3）分别为：801.776±59.6,1383.980±78.2,1490.235±89.0。瘤体平均瘤体重量（g）为：0.90±0.11,1.49±0.31,1.63±0.22。平均生长率为：20.558%,35.587%,38.211%。人胆囊癌细胞实验组、空载体阴性对照组、对照组瘤体平均体积（mm3）分别为：729.736±66.6,1493.162±98.9,1548.668±101.0。瘤体平均瘤体重量（g）为：0.82±0.10,1.68±0.21,1.90±0.25。平均生长率为：18.711%,38.286%,39.709%。两组实验组分别和空载体阴性对照组、对照组比较有统计学意义（P〈0.05）,空载体阴性对照组和对照组比较无统计学意义（P〉0.05）。结论：针对Bcl-2基因siRNA真核表达载体通过局部多点注射于移植瘤周围可以有效降低Bcl-2基因的表达,该基因沉默后肿瘤细胞增殖受到抑制,体内瘤体生长减慢。     

表皮生长因子受体单克隆抗体对裸鼠胃癌移植瘤生长和细胞增殖的影响及其分子机制

目的 观察表皮生长因子受体(EGFR)单克隆抗体西妥昔单抗((225)对裸鼠胃癌移植瘤生长的影响,并探索其分子机制.方法 筛选出高表达EGFR的胃癌细胞株SGC-7901,建立裸鼠胃癌移植瘤模型,成瘤后分为治疗组(注射(225)和对照组(注射PBS),绘制肿瘤生长曲线.采用免疫组织化学染色法,评价C225对肿瘤细胞增殖和微血管密度的影响.采用原位末端标记染色(TUNEL)技术,检测肿瘤细胞凋亡.采用免疫组化染色和Western blot技术,检测C225对转录因子Spl及EGFR表达的影响.结果 经C225处理后,裸鼠胃癌移植瘤的生长、细胞的增殖能力明显受抑,治疗组和对照组肿瘤细胞的凋亡指数分别为16.4%±0.3%和3.1%±0.9%,差异有统计学意义(P<0.001);而治疗组和对照组肿瘤组织的微血管密度并无明显差异.免疫组化染色和Western blot结果均显示,C225处理后,肿瘤细胞表面EGFR及肿瘤细胞核内Spl的表达均明显上调.结论 C225可有效抑制裸鼠胃癌皮下移植瘤的生长及细胞增殖,促进细胞凋亡,但可反馈性上调肿瘤细胞核内转录因子Spl及该药物靶点EGFR的自身表达.不同信号转导通路间可能通过转录因子Spl介导的阻断-转录激活-代偿机制,导致单一靶点阻断后的获得性耐药或使肿瘤细胞维持恶性表型.     

RNA干扰Bcl-2基因表达对人胆管癌细胞及胆囊癌细胞株裸鼠移植瘤生长的抑制

目的:探讨Bcl-2基因的小干扰RNA(siRNA)真核表达载体干扰Bcl-2基因表达对人胆管癌细胞QBC939、胆囊癌细胞GBC-SD裸鼠体内移植瘤生长的抑制作用.方法:分别制作人胆管癌细胞QBC939、胆囊癌细胞GBC-SD细胞株移植瘤模型,随机分为3组,pSilencerTM-EGFP sh515组(实验组)、pSilencerTM-EGFP shCon组(空载体阴性对照组)和对照组.实验组用Bcl-2基因的小干扰RNA(siRNA)真核表达载体多点注射于移植瘤周围,空载体阴性对照组用空载体多点注射于移植瘤周围,对照组不作处理,观察其生长情况,计算肿瘤生长体积、生长率.6周后,处死裸鼠,剥离瘤体组织进行称重,并采用免疫组化检测Bcl-2蛋白的表达.结果:成功建立裸鼠人胆管癌细胞QBC939,胆囊癌GBC-SD细胞的动物模型.胆管癌细胞实验组、空载体阴性对照组、对照组瘤体平均体积(mm3)分别为:801.776±59.6,1383.980±78.2,1490.235±89.0.瘤体平均瘤体重量(g)为:0.90±0.11,1.49±0.31,1.63±0.22.平均生长率为:20.558%,35.587%,38.211%.人胆囊癌细胞实验组、空载体阴性对照组、对照组瘤体平均体积(mm3)分别为:729.736±66.6,1493.162±98.9,1548.668±101.0.瘤体平均瘤体重量(g)为:0.82±0.10,1.68±0.21,1.90±0.25.平均生长率为:18.711%,38.286%,39.709%.两组实验组分别和空载体阴性对照组、对照组比较有统计学意义(P<0.05),空载体阴性对照组和对照组比较无统计学意义(P>0.05).结论:针对Bcl-2基因siRNA真核表达载体通过局部多点注射于移植瘤周围可以有效降低Bcl-2基因的表达,该基因沉默后肿瘤细胞增殖受到抑制,体内瘤体生长减慢.