新的抗血管生成药物阿柏西普治疗转移性结直肠癌研究进展

新生血管生成是结直肠癌发生、生长和转移的重要机制之一。阿柏西普作为血管内皮生长因子 (vascular endothelial growth factor,VEGF)的可溶性诱饵受体,作用于靶点VEGF-A、VEGF-B和胎盘生长因子(placental growth factor,PIGF)抑制肿瘤血管的生成。最近多项研究表明阿柏西普对多种实体瘤尤其转移性结直肠癌(metastatic colorectal cancer,mCRC)有明确的抗肿瘤作用。而且美国食品药品监督管理局和欧洲药物管理局已批准阿柏西普联合5-氟尿嘧啶、亚叶酸钙和伊立替康方案(5-fluorouracil,leucovorin,irinotecan,FOLFIRI)可用于二线治疗对奥沙利铂为基础的化疗方案耐药或进展的mCRC患者。该文就阿柏西普抗血管生成的作用机制和在mCRC中的临床试验作一综述。     

癌蛋白HER2在直肠癌组织中表达的临床意义

目的探讨癌蛋白HER2在直肠癌组织中表达情况及其意义。方法采用免疫组化SP方法检测直肠癌组织中HER2蛋白的表达。结果本组36例直肠癌患者中有11例表达HER2蛋白（30.6%）,当肿瘤浸润至肠壁外或发生淋巴结或肝脏转移时,其HER2蛋白阳性率明显高于无转移或浸润深度未及浆膜层的直肠癌（P〈0.05）。晚期直肠癌HER2蛋白阳性率较早期直肠癌为高（P〈0.05）,而HER2蛋白表达与肿瘤部位、大小及肿瘤细胞分化程度以及患者性别、年龄无明显关系（P〉0.05）。结论HER2在直肠癌侵袭性生长或转移中具有一定的促进作用,对预测直肠癌预后有一定帮助。     

HER2、MMP2、Leptin在结直肠癌组织中的表达及临床意义

目的探讨HER2、MMP2和Leptin在结直肠癌组织中的表达及临床意义。方法选取手术切除并经病理证实的结直肠癌标本85例作为实验组,另取85例相应癌旁正常组织作为对照组。采用免疫组化S-P法测定癌组织、癌旁正常组织中HER2、MMP2和Leptin的表达水平。结果 (1)HER2、MMP2和Leptin在85例结直肠癌组织中均有不同程度的表达:HER2阳性率为29.4%(25/85),MMP2阳性率为72.9%(62/85),Leptin阳性率为78.8%(67/85)均明显高于85例癌旁正常组织中的7.1%(6/85)、16.5%(14/85)和20.0%(17/85),差异有统计学意义(P0.01);(2)HER2、MMP2和Leptin三者表达水平均与肿瘤的浸润深度、淋巴结转移及Dukes分期呈正相关,统计学显示有差异(P0.05);(3)HER2、MMP2和Leptin三者阳性组术后1、3和5年生存率均低于阴性组术后生存率,有统计学意义(P0.05)。结论 HER2、MMP2和Leptin在结直肠癌组织中高表达,与肿瘤的生长、浸润和转移密切相关;HER2、MMP2和Leptin阳性组较低阴性组预后差。     

结直肠癌患者血清Ang-2和MMP-2水平的变化及临床意义

目的：探讨结直肠癌患者血清血管生成素2（Ang-2）和基质金属蛋白酶2（MMP-2）的表达水平变化与病情预后的关系。寻找早期预测结直肠癌发病的血清标志物,探索有效的防治措施。方法选取31例早期结直肠癌、20例晚期结直肠癌患者的血清作为研究组,40例正常健康人群的血清作为对照组。采用酶联免疫吸附实验（ELISA）法检测各组血清Ang-2和MMP-2的表达水平。结果研究组血清Ang-2和MMP-2的水平较对照组明显升高（P均〈0.01）,随着疾病临床分期的增加,研究组Ang-2和MMP-2的水平愈加增高（P均〈0.01）;相关性分析表明,Ang-2和MMP-2呈正相关（r=0.547, P=0.007）。结论结直肠癌患者血清Ang-2和MMP-2的水平与结直肠癌病情严重程度密切相关,血清Ang-2和MMP-2的检测可能可以预测结直肠癌的发生、发展。     

结直肠癌中血管内皮生长因子的表达及肿瘤血管形成的临床意义

目的 探讨血管内皮生长因子(VEGF)在结直肠癌中的表达及肿瘤血管形成的临床意义.方法 对52例结直肠癌标本应用免疫组化SP法检测VEGF蛋白的表达和微血管密度(MVD)计数,分析VEGF的表达和MVD计数及与结直肠癌临床病理特征的关系,Log-Rank时序检验VEGF蛋白的表达与生存时间的关系.结果 VEGF表达为阴性和阳性者分别为14例和38例,MVD低于和高于平均值者各有26例,两者存在显著相关性(x2=6.25,P＜0.05);VEGF的表达与Dukes分期(x2=11.46,P＜0.01)、淋巴结转移情况(x2=7.58,P＜0.01)显著相关.3年生存率为49.10%;而VEGF表达为阴性和阳性者的3年生存率分别为67.80%和13.59%(x2=17.56,P＜0.01).结论 VEGF的表达水平是影响结直肠癌患者预后的重要因素,肿瘤血管形成促进了肿瘤的侵袭和转移,这为结直肠癌抗血管形成的靶向治疗提供了分子生物学依据.     

具有抗肿瘤血管生成作用的VEGFR2抑制剂的研究进展

肿瘤血管生成是肿瘤生长与转移的重要过程。血管内皮生长因子(vascular endothelial growth factor, VEGF)和它们的受体(VEGFR1, 2, 3)调控内皮细胞的增殖与迁移,在很多肿瘤内高表达。对VEGFR的抑制已成为许多癌症的有效疗法。VEGFR2在肿瘤血管生成中起重要作用,VEGFR2磷酸化是肿瘤血管生成的重要过程,抑制这个过程是利用VEGF信号通路治疗癌症的主要机理之一。使用抗体和小分子与VEGF结合或者干扰不同的VEGFR结构域可以阻断VEGF信号通路。许多小分子VEGFR2抑制剂得到开发,大部分为多靶点抑制剂,FDA已批准一系列VEGFR2抑制剂上市。本文对已上市及进入临床研究晚期的VEGFR2小分子抑制剂及其活性、临床应用进行了综述,并对它们的构效关系作出了简要分析。发挥多靶点抑制剂的优点,规避其带来的毒副作用,是有希望的研究方向。     

结直肠癌微血管密度与血管内皮生长因子表达的临床研究

目的　探讨微血管密度 (MVD)与血管内皮生长因子 (VEGF)表达在结直肠癌中的变化 ,以及与结直肠癌临床病理间的关系。方法　应用免疫组化方法分析 5 2例结直肠癌、10例结直肠腺瘤、8例正常肠粘膜组织中的MVD、VEGF表达。结果　 (1)结直肠癌MVD(2 0 73± 10 16 )明显高于结直肠腺瘤 (8 5 3± 2 33)和正常肠粘膜组织 (3 5 0± 0 82 ) (P <0 0 1) ,结直肠腺瘤亦明显高于正常肠粘膜组织 (P <0 0 5 ) ;MVD与结直肠癌淋巴结转移、浆膜侵润、远处转移明显相关 ,DukeD、C期明显高于A、B期 (P <0 0 1) ,而与其肿瘤大小、病理类型无关 (P >0 0 5 )。 (2 )结直肠癌VEGF表达阳性率 6 5 4% (34/ 5 2例 )明显高于结直肠腺瘤、正常肠粘膜组织 ,后者分别为 30 % (3/ 10例 )、12 5 % (1/ 8例 ) ,P <0 0 1;VEGF表达与结直肠癌淋巴结侵犯 (P <0 0 5 )、浆膜浸润、远外转移明显相关 (P <0 0 1) ,但与病理类型、肿瘤大小无关。随肿瘤Duke分期进展 ,VEGF表达逐渐升高 ,DukeD、C期明显高于A、B期 (P <0 0 1,P <0 0 5 )。 (3)相关分析表明 ,MVD与VEGF呈正相关 (γ =0 5 34,P <0 0 5 )。结论　MVD、VEGF与结直肠癌生物学行为密切相关 ,VEGF表达与结直肠肿瘤血管生成有关。     

肿瘤血管生成及抗血管生成的临床应用

介绍了肿瘤血管生成的过程、特点、调控因素及其与肿瘤转移的关系，简要综述了抗血管生成的临床应用。     

EphA2与肿瘤血管生成拟态的研究进展

肿瘤血管生成是实体瘤侵袭转移的关键步骤．1971年Folkman提出了肿瘤生长依赖血管新生的假说．由此拉开了近代关于肿瘤血管生成研究的序幕。随着本世纪基因技术的飞速进展及靶向治疗的广泛应用．研究者越来越多的将抗肿瘤治疗的目光集中在抑制肿瘤新生血管生成方面．抗血管生成治疗已成为当前研究的焦点。     

血管生成因子与肿瘤血管生成和抑制的研究

近年来肿瘤血管生成已经成为肿瘤学研究的一个重要领域,迄今,人们已经发现了大约12种有血管生成活性的因子,这些因子可通过一种或几种不同的途径来诱导血管生成。本文总结了这些血管生成因子及其促血管生成的研究新进展,同时也对血管生成抑制剂的研究作了简述。     

Trastuzumab induces gastrointestinal side effects in HER2-overexpressing breast cancer patients

Summary   Purpose: To characterise the gastrointestinal toxicities associated with Trastuzumab administration in HER2-overexpressing breast cancer patients. Methods: All patients (n = 46) who received Trastuzumab as a single agent or in conjunction with conventional anti-cancer treatment within the Royal Adelaide Hospital Cancer Centre from 2002–2007 were included in this study. A retrospective analysis of case-notes was conducted to investigate the toxicities associated with Trastuzumab. Results: Trastuzumab as a single agent induced toxicities following 22% of administrations. Gastrointestinal toxicities were observed following 12% of administrations and included nausea and vomiting, diarrhoea, abdominal pain and bloating. However, other prominent toxicities that were not related to the gastrointestinal tract were also observed including fatigue and lung symptoms (10.4%). Elderly patients (≥60 years) and those with metastatic disease experienced the highest frequency of toxicity. Conclusion: Trastuzumab induces a range of gastrointestinal toxicities in HER2-overexpressing breast cancer patients. These toxicities are separate to those caused by concurrent chemotherapy and/or radiotherapy.     

梓醇通过调控肿瘤血管生成及能量代谢抑制肝癌生长

目的探讨梓醇对HepG2肝癌细胞增殖、侵袭、生长、血管生成和能量代谢的影响。方法细胞增殖实验研究梓醇对HepG2细胞体外增殖的影响;LDH试剂盒检测梓醇对HepG2细胞的毒性作用;构建人肝癌HepG2裸小鼠细胞移植瘤模型,研究梓醇对体内肝癌生长的影响;Transwell实验研究梓醇对HepG2细胞体外侵袭的影响;小管形成实验检测梓醇对HepG2细胞诱导的血管生成的影响;免疫组化研究梓醇对移植瘤中能量代谢关键指标单羧酸转运蛋白-1 (monocarboxylate transporter-1,MCT-1)、单羧酸转运蛋白-4(monocarboxylate transporter-4,MCT-4)和葡萄糖转运蛋白1(Glucose transporter 1,GLUT1)蛋白表达的影响。结果在一定浓度范围内,梓醇能够抑制HepG2细胞的体外增殖及侵袭,且具有一定的浓度依赖性;LDH检测显示其在50μmol·L~(-1)时对HepG2细胞表现出毒性作用;与对照组相比,梓醇能够显著抑制HepG2裸小鼠移植瘤的体内生长;HepG2细胞培养上清液能够显著刺激HUVEC细胞的小管形成,而梓醇能够在体外抑制HepG2细胞诱导的小管形成;梓醇能够抑制HepG2裸小鼠移植瘤组织中MCT-1,MCT4和GLUT1蛋白的表达。结论梓醇具有抑制肝癌细胞增殖、侵袭及生长的能力,其机制可能与抑制肝癌的血管生成及肿瘤能量代谢密切相关。     

Growth differentiation factor 15 (GDF15)-mediated HER2 phosphorylation reduces trastuzumab sensitivity of HER2-overexpressing breast cancer cells

Resistance to the anti-HER2 monoclonal antibody trastuzumab is a major problem in the treatment of HER2-overexpressing metastatic breast cancer. Growth differentiation factor 15 (GDF15), which is structurally similar to TGF beta, has been reported to stimulate phosphorylation of HER2. We tested the hypothesis that GDF15-mediated phosphorylation of HER2 reduces the sensitivity of HER2-overexpressing breast cancer cell lines to trastuzumab. Gene microarray analysis, real-time PCR, and ELISA were used to assess GDF15 expression. Growth inhibition and proliferation assays in response to pharmacologic inhibitors of HER2, TGF beta receptor, or Src were performed on cells stimulated with recombinant human GDF15 or stable GDF15 transfectants. Western blotting was performed to determine effects of GDF15 on HER2 signaling. Cells were infected with lentiviral GDF15 shRNA plasmid to determine effects of GDF15 knockdown on cell survival in response to trastuzumab. Cells with acquired or primary trastuzumab resistance showed increased GDF15 expression. Exposure of trastuzumab-sensitive cells to recombinant human GDF15 or stable transfection of a GDF15 expression plasmid inhibited trastuzumab-mediated growth inhibition. HER2 tyrosine kinase inhibition abrogated GDF15-mediated Akt and Erk1/2 phosphorylation and blocked GDF15-mediated trastuzumab resistance. Pharmacologic inhibition of TGF beta receptor blocked GDF15-mediated phosphorylation of Src. Further, TGF beta receptor inhibition or Src inhibition blocked GDF15-mediated trastuzumab resistance. Finally, lentiviral GDF15 shRNA increased trastuzumab sensitivity in cells with acquired or primary trastuzumab resistance. These results support GDF15-mediated activation of TGF beta receptor-Src-HER2 signaling crosstalk as a novel mechanism of trastuzumab resistance.     

Pharmacologic inhibition of mTOR improves lapatinib sensitivity in HER2-overexpressing breast cancer cells with primary trastuzumab resistance

Lapatinib, a dual EGFR/HER2 kinase inhibitor, is approved for use in patients with trastuzumab-refractory HER2- overexpressing breast cancer. Increased PI3K signaling has been associated with resistance to trastuzumab, although its role in lapatinib resistance remains unclear. The purpose of the current study was to determine if PI3K/mTOR activity affects lapatinib sensitivity. Reduced sensitivity to lapatinib was associated with an inability of lapatinib to inhibit Akt and p70S6K phosphorylation. Transfection of constitutively active Akt reduced lapatinib sensitivity, while kinase-dead Akt increased sensitivity. Knockdown of 4EBP1 also increased lapatinib sensitivity, in contrast to p70S6K knockdown, which did not affect response to lapatinib. Pharmacologic inhibition of mTOR using rapamycin or ridaforolimus increased lapatinib sensitivity and reduced phospho-Akt levels in cells that showed poor response to single-agent lapatinib, including those transfected with hyperactive Akt. Finally, combination mTOR inhibition plus lapatinib resulted in synergistic inhibition of proliferation, reduced anchorage-independent growth, and reduced in vivo tumor growth of HER2- overexpressing breast cancer cells that have primary trastuzumab resistance. Our data suggest that PI3K/mTOR inhibition is critical for achieving optimal response to lapatinib. Collectively, these experiments support evaluation of lapatinib in combination with pharmacologic mTOR inhibition as a potential strategy for inhibiting growth of HER2-overexpressing breast cancers that show resistance to trastuzumab and poor response to lapatinib.     

肿瘤血管生成的靶向调控及其药物研究进展

肿瘤血管生成(Tumor Angiogenesis)对大多数实体瘤的生长和转移具有重要意义,是多步骤多因素参与复杂的病理过程.选择肿瘤血管生成中的一些关键环节或参与的重要因子作为靶点,研制应用特异性肿瘤血管生成抑制剂或抗体,以靶向调控肿瘤血管生成,控制肿瘤的生长和转移,达到治疗肿瘤的目的.本文对近年来肿瘤血管生成机制和肿瘤血管生成抑制剂的研究进展进行综述.     

Intrathecal trastuzumab (Herceptin) and methotrexate for meningeal carcinomatosis in HER2-overexpressing metastatic breast cancer: a case report

Leptomeningeal carcinomatosis represents a rare manifestation of metastatic breast cancer (MBC). We herewith report on a patient suffering from HER2 overexpressing MBC who received intrathecal methotrexate and trastuzumab for meningeal carcinomatosis. A 48-year-old woman was diagnosed with breast cancer in December 2002. Following surgery, six cycles of adjuvant FE100C plus irradiation and, subsequently for 1 year, trastuzumab were given. As a result of disseminated metastatic spread in October 2005, the patient received whole-brain radiotherapy for symptomatic central nervous system involvement, and was put on several trastuzumab-based combination regimens (capecitabine, vinorelbine, paclitaxel). In June 2006, the patient developed clinical signs of terminal cone involvement with overflow incontinence and paraparesis of the legs. Immediate radiation led to partial relief from clinical symptoms. Subsequently, the patient was put on the tyrosine kinase inhibitor lapatinib and capecitabine (August to October 2007), but on November 6th the patient suffered again from overflow incontinence and weakness of the legs. Failing to respond to lapatinib, the patient received gemcitabine/cisplatin and, additionally, was recommenced on intravenous trastuzumab. Owing to progressive leptomeningeal disease, the patient received repeated doses of intrathecal methotrexate and trastuzumab. Within 2 weeks and four intrathecal treatments, cerebrospinal fluid cytology showed the absence of tumor cells. Moreover, a striking clinical improvement with resolution of the paraparesis of the legs and overflow incontinence was observed. This case report gives details regarding the clinical course of a breast cancer patient who received intrathecal trastuzumab and methotrexate via lumbar puncture for meningeal carcinomatosis of HER2-overexpressing MBC.     

Bispecific antibody simultaneously targeting PD1 and HER2 inhibits tumor growth via direct tumor cell killing in combination with PD1/PDL1 blockade and HER2 inhibition

Immune checkpoint blockade has shown significant clinical benefit in multiple cancer indications,but many patients are either refractory or become resistant to ...     

Trastuzumab and vinorelbine as first-line therapy for HER2-overexpressing metastatic breast cancer: multicenter phase II and pharmacokinetic study in Japan

Tolerability and response rate to weekly combination chemotherapy with trastuzumab and vinorelbine in Japanese women with HER2-overexpressing breast cancer not previously receiving either therapy were assessed. Tumor response was evaluated every 4 weeks and adverse events were graded. A total of 23 patients from six participating centers in Japan were enrolled. Median dose intensity of vinorelbine was 16.9 mg/m2/week and response rate was 73% (complete response+partial response); complete response=9%, partial response=64%, and progressive disease=5%. Time to progression was 361 days, with 75.0% of liver metastases and 60% of lung metastases responding to this treatment. The most common adverse events were leukocytopenia and neutropenia (96%); however, hematologic toxicity associated with vinorelbine was manageable by adjusting the dose. No pharmacokinetic differences for vinorelbine were found between single administration and combination with trastuzumab. This combination therapy produced high response rates and good tolerability, indicating a promising role in first-line chemotherapy for HER2-overexpressing metastatic breast cancer in Japan.