Antiangiogenic agents significantly improve survival in tumor-bearing mice by increasing tolerance to chemotherapy-induced toxicity

Chemotherapy-induced broad toxicities are the leading cause of the drug-induced mortality in cancer patients. Antiangiogenic drugs (ADs) in combination with chemotherapy are widely used as front-line therapy for the treatment of various human cancers. However, the beneficial mechanisms underlying combination therapy are poorly understood. Here we show that, in several murine tumor models, administration of sunitinib markedly reduced chemotherapy-induced bone marrow toxicity. Intriguingly, in a sequential treatment regimen, delivery of ADs followed by chemotherapy demonstrated superior survival benefits compared with simultaneous administration of two drugs. In murine tumor models, we show that VEGF increased chemotoxicity by synergistically suppressing bone marrow hematopoiesis with cytostatic drugs. These findings shed light on molecular mechanisms by which ADs in combination with chemotherapy produce survival benefits in cancer patients and provide conceptual information guiding future designs of clinical trials, current practice, and optimization of ADs for the treatment of cancer.     

Anti-VEGF single-chain antibody GLAF-1 encoded by oncolytic vaccinia virus significantly enhances antitumor therapy

We previously reported that the replication-competent vaccinia virus (VACV) GLV-1h68 shows remarkable oncolytic activity and efficacy in different animal models as a single treatment modality and also in combination with chemotherapy [Yu YA, et al. (2009) Mol Cancer Ther 8:141–151]. Here, we report the construction of 3 VACV strains encoding GLAF-1, a previously undescribed engineered single-chain antibody (scAb). This unique scAb is transcribed from 3 vaccinia promoters (synthetic early, early/late, and late) and directed against both human and murine VEGFs. The expression of GLAF-1 was demonstrated in cell cultures. Also, the replication efficiency of all GLAF-1–expressing VACV strains in cell culture was similar to that of the parental GLV-1h68 virus. Successful tumor-specific delivery and continued production of functional scAb derived from individual VACV strains were obtained in tumor xenografts following a single intravenous injection of the virus. The VACV strains expressing the scAb exhibited significantly enhanced therapeutic efficacy in comparison to treatment of human tumor xenografts with the parental virus GLV-1h68. This enhanced efficacy was comparable to the concomitant treatment of tumors with a one-time i.v. injection of GLV-1h68 and multiple i.p. injections of Avastin. Taken together, the VACV-mediated delivery and production of immunotherapeutic anti-VEGF scAb in colonized tumors may open the way for a unique therapy concept: tumor-specific, locally amplified drug therapy in humans.     

Shwachman-Diamond syndrome: an inherited model of aplastic anaemia with accelerated angiogenesis

Bone marrow angiogenesis is increased in myelodysplastic syndromes (MDS) and acute myeloid leukaemia (AML), but has not been studied in inherited or acquired marrow failure syndromes. Shwachman-Diamond syndrome (SDS) carries a high risk of MDS/AML and is characterised by marrow stromal dysfunction. Compared with controls, SDS patients without MDS/AML had higher marrow microvessel density. Stromal VEGF gene expression, stromal vascular endothelial growth factor (VEGF) secretion and VEGF levels in serum and marrow mononuclear cells were normal. Future studies should investigate the mechanism for increased angiogenesis in SDS, and whether SDS marrow, with its increased angiogenesis, promotes progression of malignant clones.     

Different Mechanisms Lead to the Angiogenic Process Induced by Three Adenocarcinoma Cell Lines

Neoangiogenesis is essential for tumor and metastasis growth, but this complex process does not follow the same activation pathway, at least in tumor cell lines originated from different murine mammary adenocarcinomas. LMM3 cells were the most potent to stimulate new blood vessel formation. This response was significantly reduced by preincubating cells with indomethacin and NS-398, non-selective cyclooxygenase (COX) and COX-2 selective inhibitors, respectively. COX-1 and COX-2 isoenzymes were both highly expressed in LMM3 cells, and we observed that indomethacin was more effective than NS-398 to inhibit prostaglandin E2 (PGE2) synthesis. In addition, nitric oxide synthase (NOS) inhibitors, Nomega monomethyl L-arginine and aminoguanidine, also reduced LMM3-induced angiogenesis and nitric oxide (NO) synthesis as well. NOS2 > NOS3 proteins and arginase II isoform were detected in LMM3 cells by Western blot. The latter enzyme was also involved in the LMM3 neovascular response, since the arginase inhibitor, Nomega hydroxy L-arginine reduced the angiogenic cascade. On the other hand, parental LM3 cells were able to stimulate neovascularization via COX-1 and arginase products since only indomethacin and Nomega hydroxy L-arginine, which diminished PGE2 and urea synthesis, respectively, also reduced angiogenesis. In turn, LM2 cells angiogenic response could be due in fact to PGE2-induced VEGF liberation that stimulated neoangiogenesis at very low levels of NO.     

A monoclonal antibody that blocks VEGF binding to VEGFR2 (KDR/Flk-1) inhibits vascular expression of Flk-1 and tumor growth in an orthotopic human breast cancer model

Vascular endothelial growth factor (VEGF) is a primary stimulant of tumor angiogenesis. We previously raised a neutralizing anti-VEGF monoclonal antibody 2C3 that blocks the interaction of VEGF with VEGFR2 (KDR/Flk-1) but not with VEGFR1 (FLT-1/flt-1). Here, we describe the therapeutic effects of 2C3 on tumor growth in an orthotopic model of MDA-MB-231 human breast carcinoma implanted in the mammary fat pads (MFP) of nude mice. Administration of 2C3 to mice with 100–150 mm³ tumors inhibited tumor growth by 75%, as compared to recipients of the isotype-matched irrelevant control IgG, C44. Treatment with 2C3 also inhibited the establishment of tumor colonies and reduced tumor burden in the lungs of mice injected intravenously with MDA-MB-231 cells. No toxicity was observed in these studies. The mean microvascular density (MVD) of tumors in 2C3-treated mice was 55 ± 5 per mm², as compared to 188 ± 5 per mm² in the C44-treated control group. The decrease in MVD closely correlated with the degree of inhibition of tumor growth. Treated tumors mostly contained mid-size and large vessels. Microvessels were mainly confined to the peripheral layer of tumor that bordered on the normal MFP epithelium. Tumor vessels had decreased expression of VEGFR2, indicating that neutralization of tumor-derived VEGF by 2C3 down-regulates the expression of VEGFR2 on tumor vasculature. This, in turn, may limit re-initiation of angiogenesis by either tumor-derived or stromal VEGF. These findings suggest that 2C3 is a candidate for treating primary cancer and for preventing the outgrowth of tumor metastases in cancer patients.     

麝黄消瘤方对小鼠肝癌血管生成的抑制作用

目的:观察麝黄消瘤方(SHXLF)对肝癌H22模型小鼠癌细胞侵袭和转移的影响,探讨其作用机制。方法:以小鼠H22肝癌淋巴道转移模型为对象,观察其淋巴结指数、脾指数、胸腺指数,光镜下观察肝癌H22细胞局部侵袭和淋巴结转移程度。免疫组化SP法观察局部瘤组织血管内皮细胞生长因子(VEGF)表达水平和微血管密度(MVD)。结果:麝黄消瘤方可使局部瘤组织的侵袭和腘窝淋巴结转移程度及淋巴结指数有降低趋势;大中剂量组可使胸腺指数明显升高(P<0.05)。中药各治疗组可明显降低肝癌组织VEGF表达水平和MVD(P<0.05)。结论:SHXLF可抑制H22肝癌小鼠癌组织在局部及淋巴结的侵袭转移程度。其作用机制可能是通过调整免疫功能,杀伤癌细胞,抑制肿瘤血管生成(降低VEGF和MVD)而实现的。     

Pulmonary Tumor Thrombotic Microangiopathy Due to Gastric Cancer Diagnosed Antemortem by a Cytological Examination of Aspirated Pulmonary Artery Blood

A 66-year-old Japanese man receiving systemic chemotherapy for advanced gastric cancer presented with exertional dyspnea. D-dimer was elevated in the blood. Echocardiography revealed pulmonary hypertension, and a ventilation-perfusion scan indicated decreased perfusion in the bilateral lungs. Cardiac catheterization showed no evidence of pulmonary artery embolization and revealed cytologically confirmed adenocarcinoma. Thus, pulmonary tumor thrombotic microangiopathy (PTTM) was diagnosed. The patient died of respiratory failure on the 17th hospitalization day despite systemic chemotherapy. Retrospective serological testing revealed increased vascular endothelial growth factor in the pulmonary artery blood. This is a rare case with antemortem cytologically proven PTTM mediated by VEGF.     

小鼠口腔癌不同时期淋巴结和骨髓的VEGF表达情况及其微环境对淋巴道转移的影响

目的 探讨小鼠口腔癌不同时期淋巴结和骨髓的血管内皮生长因子(VEGF)表达情况,及其微环境对口腔癌淋巴道转移的影响.方法 选入40只6周龄雄性健康Balb/c小鼠,将其随机分为A、B、C、D、E组,每组8只.采用4-硝基喹啉-1-氧化物(4-NQO)饮水法构建小鼠口腔癌淋巴道转移模型.其中A组为正常小鼠;B组小鼠舌部黏...     

TFPI-2、VEGF在非小细胞肺癌中的表达及相关性研究

目的研究组织因子途径抑制物-2(tissue factor pathway inhibitor-2,TFPI-2)、血管内皮生长因子(vascular endotheli-al growth factor,VEGF)在非小细胞肺癌(non-small cell lung cancer,NSCLC)中的表达及其间的相关性。方法采用免疫组化法检测60例NSCLC组织TFPI-2、VEGF的表达及CD31单克隆抗体标记的微血管密度(MVD)。结果 NSCLC中临床分期为Ⅰ、Ⅱ、Ⅲ期的患者中TFPI-2表达阳性率分别为75.8%、25.0%和40.0%(P=0.003),无淋巴结转移和有淋巴结转移的患者中TF-PI-2表达阳性率分别为66.7%、38.1%(P=0.033)。临床分期为Ⅰ、Ⅱ、Ⅲ期的患者中EVGF表达阳性率分别为60.6%、88.3%和93.3%(P=0.040),无淋巴结转移和有淋巴结转移的患者中VEGF表达阳性率分别为64.1%、90.5%(P=0.028)。NSCLC组织中的TFPI-2的表达与VEGF的表达呈负相关(r=-0.351),差异有统计学意义(P=0.004)。高、低MVD组中的TFPI-2阳性表达率分别为41.2%、76.9%(P=0.006)。高、低MVD组中的VEGF阳性表达率分别为76.5%、30.87%(P=0.000)。结论 NSCLC中TFPI-2可能通过下调VEGF的表达抑制肿瘤新生血管的形成,从而抑制NSCLC的生长、浸润及转移。     

Cardioneuroablation for treatment of carotid sinus syndrome secondary to oropharyngeal squamous cell cancer

Head and neck tumors can rarely cause carotid sinus syndrome and this often resolves by surgical intervention or palliative chemoradiotherapy. If these modalities are not an option or are ineffective, the most preferred treatment is permanent pacemaker therapy. Here, we present the first case of cardioneuroablation treatment performed in patient with oropharyngeal squamous cell cancer who developed recurrent asystole and syncope attacks due to compression of the carotid sinus on neck movement.     

Adipokines in the HIV/HAART-associated lipodystrophy syndrome

The use of highly active antiretroviral therapy (HAART) in the treatment of human immunodeficiency virus has dramatically altered both the landscape of this disease and the prognosis for those affected. With more patients now receiving HAART, adverse effects such as lipodystrophy and metabolic syndrome have emerged. In HIV/HAART-associated lipodystrophy syndrome (HALS), patients demonstrate fat maldistribution with dyslipidemia, insulin resistance, and other metabolic complications. Recent studies have contributed to the elucidation of the pathophysiological abnormalities seen in this syndrome and have provided guidance for the study and use of potential treatments for these patients, but widely accepted guidelines have not yet been established. Two adipokines, leptin and adiponectin, are decreased in patients with HALS and lipoatrophy or lipodystrophy. Further, recent proof-of-concept clinical trials have proven the efficacy of leptin replacement and medications that increase circulating adiponectin levels in improving the metabolic profile of HALS patients. This review article highlights recent evidence on leptin replacement and compares leptin’s efficacy to that of other treatments, including metformin and thiazolidinediones, on metabolic abnormalities such as impaired insulin-glucose homeostasis associated with lipodystrophy in patients receiving HAART. It is hoped that forthcoming large phase III clinical trials will allow the addition of leptin to our therapeutic armamentarium for use in patients suffering from this disease state.     

The role of low-grade inflammation in the polycystic ovary syndrome

PCOS is not only the most frequent cause of oligomenorrhea in young women, but also a metabolic disorder characterized by insulin resistance, glucose intolerance, dyslipidemia, and obesity, especially the visceral phenotype. PCOS represents a broad spectrum of endocrine and metabolic alterations which change with age and with increasing adiposity. In fact, during adolescence and youth the predominant clinical manifestations of PCOS are menstrual abnormalities, hirsutism and acne, whereas in peri-menopausal and post-menopausal periods metabolic disorders and an increased risk for cardiovascular diseases prevail. The pathogenetic links between PCOS and metabolic or cardiovascular complications are still debated. However, recent evidence has been focused on a condition of low-grade chronic inflammation as a potential cause of the long-term consequence of the syndrome.     

Heterogeneity of hepatocellular carcinoma contributes to cancer progression

Hepatocellular carcinoma (HCC) is a highly heterogeneous disease displaying differences in angiogenesis, extracellular matrix proteins, the immune microenvironment and tumor cell populations. Additionally, genetic variations and epigenetic changes of HCC cells could lead to aberrant signaling pathways, induce cancer stem cells and enhance tumor progression. Thus, the heterogeneity in HCC contributes to disease progression and a better understanding of its heterogeneity will greatly aid in the development of strategies for the HCC treatment.