18 research outputs found

    Reply: Did animal offer relevant model for bevacizumab testing?

    Get PDF
    growth factor (VEGF)-blocking antibodies completely inhibit the growt

    Combined effects of bevacizumab with erlotinib and irradiation: a preclinical study on a head and neck cancer orthotopic model

    Get PDF
    Clinical benefit has been demonstrated in patients with head and neck tumours receiving an anti-epidermal growth factor receptor (EGFR) agent in combination with radiotherapy (RT). Recent preclinical and clinical studies suggest beneficial effects from combining anti-angiogenic drugs with RT. To investigate the effect of combining these approaches, we evaluated in vivo the anti-tumour efficacy of the anti-angiogenic compound bevacizumab, a highly specific monoclonal antibody directed against the vascular endothelial growth factor (VEGF), erlotinib, an EGFR tyrosine kinase inhibitor, and irradiation given alone and in combination. Investigations were performed using a VEGF-secreting human head and neck tumour cell line, CAL33, with a high EGFR content, injected as orthotopic xenografts into the mouth floor of nude mice. Three days after tumour cell injection, bevacizumab (5 mg kg−1, 5 days a week, i.p.), erlotinib (100 mg kg−1, 5 days a week, orally) and irradiation (6 Gy, 3 days a week) were administered alone and in combination for 10 days. As compared with the control, concomitant administration of drugs produced a marked and significant supra-additive decrease in tumour mass; the addition of irradiation almost completely abolished tumour growth. The drug association markedly reduced the number of metastatic nodes and the triple combination significantly reduced the total number of pathologically positive lymph nodes as compared with controls. The RT-induced proliferation, reflected by Ki67 labelling, was reduced to control level with the triple combination. Radiotherapy induced a strong and very significant increase in tumour angiogenesis, which was no longer observed when combined with erlotinib and bevacizumab. The efficacy of the combination of bevacizumab+erlotinib and RT may be of clinical importance in the management of head and neck cancer patients

    Acceleration of clear cell renal cell carcinoma growth in mice following bevacizumab/Avastin treatment: the role of CXCL cytokines.

    No full text
    International audienceThe anti-VEGF targeted antibody bevacizumab (BVZ) has been approved for treating renal cell carcinomas (RCCs). Although BVZ increases the progression-free survival of patients with metastatic RCC, the effect on overall survival is poor. To gain insight into the limited efficacy of BVZ on overall survival, we analyzed patient samples of RCC for angiogenic factors that may participate in escape from anti-VEGF therapy. Our study shows that the level of vascular endothelial growth factor (VEGF) in tumors was increased compared with normal tissue. The level of interleukin-8/CXCL8, a pro-angiogenic member of the CXCL family of cytokines, was also increased in tumors. These observations gave us a good reason to analyze the combined effects of BVZ and anti-CXCL8 antibodies on tumor growth. Surprisingly, we report that BVZ accelerates the growth of RCC in nude mice with in vivo selection of tumor cells with an increased growth capacity. Downregulation of receptor tyrosine phosphatase-κ, a phosphatase implicated in EGF receptor regulation, may partly explain this phenomenon. Modification of the vascular network and development of lymphatic vessels through VEGF-C production and compensatory production of pro-angiogenic CXCL cytokines were also observed. The apparent normalization of the vascular network prompted us to associate BVZ with the chemotherapeutic agent paclitaxel. While efficient in vitro, paclitaxel did not reverse the anti-VEGF effects in vivo. Anti-CXCL8-targeting antibodies were promising as they decreased intra-tumor VEGF production; decreased the pro-angiogenic CXCL/anti-angiogenic CXCL ratio and did not induce lymphangiogenesis. These observations hold clinical implication as they highlight putative markers implicated in escape from BVZ treatment. They also recommend proceeding with caution in the use of anti-VEGF therapy alone for treatment of RCC

    Br. J. Cancer

    No full text
    BACKGROUND: To test the prognostic value of tumour protein and genetic markers in colorectal cancer (CRC) and examine whether deficient mismatch repair (dMMR) tumours had a distinct profile relative to proficient mismatch repair (pMMR) tumours. METHODS: This prospective multicentric study involved 251 stage I-III CRC patients. Analysed biomarkers were EGFR (binding assay), VEGFA, thymidylate synthase (TS), thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD) expressions, MMR status, mutations of KRAS (codons 12-13), BRAF (V600E), PIK3CA (exons 9 and 20), APC (exon 15) and P53 (exons 4-9), CpG island methylation phenotype status, ploidy, S-phase, LOH. RESULTS: The only significant predictor of relapse-free survival (RFS) was tumour staging. Analyses restricted to stage III showed a trend towards a shorter RFS in KRAS-mutated (P=0.005), BRAF wt (P=0.009) and pMMR tumours (P=0.036). Deficient mismatch repair tumours significantly demonstrated higher TS (median 3.1 vs 1.4) and TP (median 5.8 vs 3.5) expression relative to pMMR (P<0.001) and show higher DPD expression (median 14.9 vs 7.9, P=0.027) and EGFR content (median 69 vs 38, P=0.037) relative to pMMR. CONCLUSIONS: Present data suggesting that both TS and DPD are overexpressed in dMMR tumours as compared with pMMR tumours provide a strong rationale that may explain the resistance of dMMR tumours to 5FU-based therapy

    A prospective multicentre REFCOR study of 470 cases of head and neck Adenoid cystic carcinoma: epidemiology and prognostic factors

    No full text
    International audienceBackground: Adenoid cystic carcinoma (ACC) accounts for 1% of malignant head and neck tumours [1] and 10% of salivary glands malignant tumours. The main objective of our study is to investigate the prognostic factors influencing the event-free survival (EFS) of patients with ACC. Patients and methods: A multicentre prospective study was conducted from 2009 to 2018. All 470 patients with ACC whose survival data appear in the REFCOR database were included in the study. The main judgement criterion was EFS. Both a bivariate survival analysis using log-rank test and a multivariate using Cox model were performed using the R software. Results: Average age was 55 years. Females accounted for 59.4% of the cohort. The body mass index (BMI) was normal in 86% of cases. Tumours were located in minor salivary glands in 60% of cases. T3/T4 stages represented 58%; 89% of patients were cN0. histological grade III was observed on 21% of patients. The EFS and overall 5-year survival rates were 50% and 85%, respectively. After adjustment, the most significant pejorative prognostic factors were age >= 65 years (hazard ratio [HR] = 1.67), BMI<16.5 (HR = 2.62), and lymph node invasion cN (HR = 2.08). Conclusion: Age, BMI and N stage are the three main clinical prognostic factors determining EFS identified in this prospective series of patients with ACC. Such findings open new research perspectives on the influence of these components on initial patient care. (C) 2020 Elsevier Ltd. All rights reserved
    corecore