Prospective analysis of the impact of VEGF-A gene polymorphisms on the pharmacodynamics of bevacizumab-based therapy in metastatic breast cancer patients.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: • Functional polymorphisms on the VEGF-A gene, known to be linked to cancer risk or to VEGF-A plasma concentrations, have been identified. So far, limited knowledge has been published on the relationships between toxicity/efficacy of bevacizumab-based therapy and VEGF-A polymorphisms (tumoral DNA). We therefore prospectively tested the impact of these five gene polymorphisms (blood DNA) on the pharmacodynamics of bevacizumab-based treatment administered in metastatic breast cancer patients. WHAT THIS STUDY ADDS: • Present data obtained from a prospective study suggest a role for VEGF-A 936C > T polymorphism as a potential predictor of time to progression in breast cancer patients receiving bevacizumab-containing therapy. Also, the VEGF-A-634G > C polymorphism was linked to bevacizumab-related toxicity. AIMS To test prospectively the impact of VEGF-A gene polymorphisms on the pharmacodynamics of bevacizumab-chemotherapy in breast cancer patients. METHODS: As part of the single-arm MO19391 trial, 137 women with locally recurrent or metastatic breast cancer receiving first-line bevacizumab-containing therapy were analysed. Patients received bevacizumab associated (76%) or not (24%) with taxane-based chemotherapy. Clinical evaluation included clinical response, time to progression (TTP) and a toxicity score corresponding to the sum of each maximum observed toxicity grade (hypertension, haemorrhage, arterial and venous thrombo-embolism). Functional VEGF-A polymorphisms at position -2578 C > A, -1498 T > C, -1154 G > A, -634 G > C and 936 C > T were analysed by PCR-RFLP (blood DNA). RESULTS: Overall response rate (complete response (CR) + partial response (PR)) was 61%. Median TTP was 11 months. None of the VEGF-A polymorphisms was significantly linked to clinical response. Analysis of the 936C > T polymorphism revealed that the 96 patients homozygous for the 936C allele exhibited a marked tendency for a shorter TTP (median 9.7 months) than the 32 patients bearing the 936T allele (median 11.5 months, P= 0.022) of which 30 were CT and two were homozygous TT. Other polymorphisms did not influence TTP. VEGF-A-634 G > C was significantly related to the toxicity score with 39%, 49% and 81% of patients with score >1 in GG, GC and CC patients, respectively (P= 0.01). CONCLUSIONS: The role for VEGF-A 936C > T polymorphism as a potential marker of TTP in breast cancer patients receiving bevacizumab-containing therapy concords with the known impact of VEGF-A 936C > T polymorphism on VEGF-A expression.

Tumor aromatase expression as a prognostic factor for local control in young breast cancer patients after breast-conserving treatment.

INTRODUCTION: We sought to determine whether the levels of expression of 17 candidate genes were associated with locoregional control after breast-conserving treatments of early-stage breast cancers in young, premenopausal women. METHODS: Gene expression was measured by using RT-PCR in the breast tumors of a series of 53 young (younger than 40 years), premenopausal patients. All treatments consisted of primary breast-conserving surgery followed by whole-breast radiotherapy (+/- regional lymph nodes) with or without systemic treatments (chemotherapy +/- hormone therapy). The median follow-up was 10 years. RESULTS: The 10-year locoregional control rate was 70% (95% CI, 57% to 87%). In univariate analysis, no clinical/pathologic prognostic factors were found to be significantly associated with decreased locoregional control. Expression of three genes was found to be significantly associated with an increased locoregional recurrence rate: low estrogen-receptor beta, low aromatase, and high GATA3. Two others were associated with only a trend (P < 0.10): low HER1 and SKP2. In multivariate analysis, only the absence of aromatase was significantly associated with an increased locoregional recurrence rate (P = 0.003; relative risk = 0.49; 95% CI 0.29 to 0.82). CONCLUSIONS: Recent data give credit to the fact that breast cancer in young women is a distinct biologic entity driven by special oncogenic pathways. Our results highlight the role of estrogen-signaling pathways (mainly CYP19/aromatase, GATA3, and ER-beta) in the risk of locoregional recurrence of breast cancer in young women. Confirmation in larger prospective studies is needed.

Urokinase-type plasminogen activator and plasminogen-activator-inhibitor type 1 predict metastases in good prognosis breast cancer patients.

UNLABELLED: This retrospective analysis was designed to confirm the predictive role of urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitor type I (PAI-1) in the outcome of early stage, node-negative breast cancer patients. PATIENTS AND METHODS: Node-negative patients having not received adjuvant chemotherapy, and for whom frozen samples were available, were selected. RESULTS: Among the 169 patients included, 56.8% presented with uPA >3 ng/mg of proteins and/or PAI-1 >14 ng/mg of proteins. The median follow-up was 73 months. Significant correlations were found between uPA and disease-free survival (p [univariate]=0.003; p [multivariate]=0.01), and between uPA, PAI-1, and uPA plus PAI-1 and distant relapses (p=0.002). No significant correlation was found between uPA/PAI-1 and the risk of locoregional recurrence. CONCLUSION: This study demonstrated that uPA and PAI-1 are useful predictors of distant metastases in a subset of early stage, node-negative breast cancer patients.

A new model of patient tumor-derived breast cancer xenografts for preclinical assays.

PURPOSE: To establish a panel of human breast cancer (HBC) xenografts in immunodeficient mice suitable for pharmacologic preclinical assays. EXPERIMENTAL DESIGN: 200 samples of HBCs were grafted into Swiss nude mice. Twenty-five transplantable xenografts were established (12.5%). Their characterization included histology, p53 status, genetic analysis by array comparative genomic hybridization, gene expression by Western blotting, and quantitative reverse transcription-PCR. Biological profiles of nine xenografts were compared with those of the corresponding patient's tumor. Chemosensitivities of 17 xenografts to a combination of Adriamycin and cyclophosphamide (AC), docetaxel, trastuzumab, and Degarelix were evaluated. RESULTS: Almost all patient tumors established as xenografts displayed an aggressive phenotype, i.e., high-grade, triple-negative status. The histology of the xenografts recapitulated the features of the original tumors. Mutation of p53 and inactivation of Rb and PTEN proteins were found in 83%, 30%, and 42% of HBC xenografts, respectively. Two HBCx had an ERBB2 (HER2) amplification. Large variations were observed in the expression of HER family receptors and in genomic profiles. Genomic alterations were close to those of original samples in paired tumors. Three xenografts formed lung metastases. A total of 15 of the 17 HBCx (88%) responded to AC, and 8 (47%) responded to docetaxel. One ERBB2-amplified xenograft responded to trastuzumab, whereas the other did not. The drug response of HBC xenografts was concordant with that of the patient's tumor in five of seven analyzable cases. CONCLUSIONS: This panel of breast cancer xenografts includes 15 triple-negative, one ER positive and 2 ERBB2 positive. This panel represents a useful preclinical tool for testing new agents and protocols and for further exploration of the biological basis of drug responses.

Androgens repress the expression of the angiogenesis inhibitor thrombospondin-1 in normal and neoplastic prostate.

In order to understand why the angiogenesis inhibitor thrombospondin-1 (TSP1) is often, although not always, associated with prostatic tumors, we have investigated its relationship with the testosterone and the vasculature on which both normal and tumorigenic prostatic epithelia depend. In vivo, androgen withdrawal led to increased TSP1 production and decreased vascularization in the normal rat prostate which was reversed by androgen replacement. Androgen repression of TSP1 production occurred at the transcriptional level and was dependent on the presence of the first intron of the TSP1 gene. In an experimental model of prostate tumorigenesis, TSP1, when delivered by admixed stromal fibroblasts, markedly delayed LNCaP tumor growth and limited tumor vascularization. However, prolonged exposure to TSP1 resulted in the growth of tumors secreting high levels of vascular endothelial growth factor in the bloodstream of tumor-bearing animals and tumor growth was no longer sensitive to TSP1 inhibitory effects. Clinical evidence also suggested that prostate carcinomas are able to adapt to escape the antiangiogenic effects of TSP1. In human androgen-dependent localized prostate carcinomas, TSP1 expression was inversely correlated with blood vessel density. Androgen deprivation in patients with hormone-responsive tumors led to increased TSP1 expression and vascular regression. In contrast, despite a sustained expression in the tumor bed, TSP1 was no longer associated with decreased vascularization in hormone-refractory prostate tumors. Overall, these results suggest that the high in situ TSP1 exposure triggered by androgen deprivation in patients with prostate cancer could lead to early tumor resistance. Such patients could benefit from a combination of androgen deprivation and antiangiogenic therapy in order to minimize the induction of such tumor escape.

Incidence of H1N1 2009 virus infection through the analysis of paired plasma specimens among blood donors, France.

BACKGROUND: Knowledge of the age-specific prevalence of seroprotection and incidence of seroconversion infection is necessary to complement clinical surveillance data and statistical models. It provides the basis for estimating the future impact of influenza A (H1N1pdm09) and implementing appropriate prevention and response strategies. METHODS: Using a cross-sectional design, two-stage stratified sampling and paired plasma samples, we estimated the age-specific prevalence of a protective level of H1N1pdm09 antibodies in the French adult population before and after the 2009/10 pandemic, and the proportion of those susceptible that seroconverted due to infection, from a single sample of 1,936 blood donors aged 20-70 years in mainland France in June 2010. Samples with a haemagglutination inhibition (HI) titre ≥1∶40 were considered seropositive, and seroconversion due to infection was defined as a 4-fold increase in titre in the absence of H1N1pdm09 vaccination or pre-pandemic seropositivity. RESULTS: Out of the 1,936 donors, 1,708 were included in the analysis. Seroprevalence before the pandemic was 6.7% (95% CI 5.0, 8.9) with no significant differences by age-group (p = 0.3). Seroprevalence afterwards was 23.0% (95% CI 17.7, 29.3) with 20-29 year olds having a higher level than older groups (p<0.001). Seroconversion due to infection was 12.2% (95% CI 6.9, 20.5). Younger age-group, vaccination against H1N1 and being seropositive before the pandemic were strongly associated with post-pandemic seropositivity. CONCLUSIONS: Before the 2009/2010 winter influenza season, only 6.7% of the French mainland population aged 20-70 had a level of antibodies usually considered protective. During the first pandemic wave, 12.2% of the population seroconverted due to infection and the seroprevalence after the wave rose to 23%, either due to prepandemic seropositivity, infection or vaccination. This relatively low latter figure contributed to an extension of target groups for influenza vaccination for the 2010/2011 season.

Cross-validation study for epidermal growth factor receptor and KRAS mutation detection in 74 blinded non-small cell lung carcinoma samples: a total of 5550 exons sequenced by 15 molecular French laboratories (evaluation of the EGFR mutation status for the administration of EGFR-TKIs in non-small cell lung carcinoma [ERMETIC] project--part 1).

INTRODUCTION: The Evaluation of the epidermal growth factor receptor (EGFR) Mutation status for the administration of EGFR-Tyrosine Kinase Inhibitors in non-small cell lung Carcinoma (NSCLC) (ERMETIC) project part 1 assessed the accuracy of EGFR and KRAS mutations detection in NSCLC among 15 French centers. METHODS: The 15 ERMETIC centers selected 74 NSCLC surgical specimens from previously untreated patients. Paraffin and paired frozen DNA were sequenced for EGFR exons 18 to 21 and KRAS exon 2 by an external molecular laboratory, yielding a gold standard. The 74 blinded paraffin DNAs were redistributed to the 15 ERMETIC laboratories for sequencing of a total of 5550 exons. Results were compared with the gold standard and between centers by discordance rates and kappa statistics. RESULTS: The gold standard included 39 mutated samples with 22 EGFR and 17 KRAS mutated samples. Kappa statistics showed that 10, 6, and 6 of the 15 ERMETIC centers had a moderate to good kappa score, when compared with external laboratory for EGFR exon 19, EGFR exon 21, and KRAS exon 2, respectively. Kappa statistics showed moderate score between centers which increased to good for EGFR exon 19 mutation when removing 16 poor-quality samples with high nonamplificable rates. CONCLUSIONS: Paraffin-embedded specimens may represent a suitable source of DNA for sequencing analyses in ERMETIC centers. EGFR exon 19 deletions were most accurately detected by ERMETIC centers. Ease and accuracy of results, depended more on the quality of sample than on the difference in molecular sequencing procedures between centers, emphasize the need of preanalytical quality control programs.

Concordant analysis of KRAS status in primary colon carcinoma and matched metastasis.

KRAS somatic mutations are the main predictive factor for non response to EGFR-targeted monoclonal antibodies in metastatic colorectal cancer (mCRC) patients. We compared KRAS mutational status in the primary tumour and the corresponding metastases (1 to 4 sites) in 38 mCRC patients. KRAS mutational status was analysed using direct sequencing, SNAPShot multiplex PCR and Scorpion Taqman PCR analysis. Results showed 54% of primary tumours had KRAS mutations. A concordance of 97% between primaries and metastatic sites was observed. A tumour heterogeneity was also demonstrated in 5% of mCRC. One case with three different primary tumours harboured three different KRAS mutations, and only one was represented in the unique metastasis of this patient. We concluded there was a high concordance in the KRAS status between the primary tumour and metastases. More than one informative block and more sensitive assay may increase the accuracy of KRAS status determination.

[Trastuzumab (Herceptin) and breast cancer: mechanisms of resistance]. / Trastuzumab (Herceptin) et cancer du sein: mécanismes de résistance.

The detection of overexpression of human epidermal growth factor receptor 2 (HER2) in some breast cancer tumors has led to the development of a targeted treatment that is tumor selective, effective at extending life expectancy in the patients with advanced or early breast cancers. Trastuzumab (Herceptin), a humanized monoclonal antibody to HER2 is indicated for patients whose tumor demonstrates an amplified copy number for the HER2 oncogene and/or overexpresses the HER2 oncoprotein. Despite a high level of efficacy in combination with chemotherapy, trastuzumab as single agent has limited effectiveness (up to 30% response rates) and patients who respond to trastuzumab will relapse despite continued treatment. The mechanism of trastuzumab action is not fully understood but has been related to cell cycle inhibition. As to mechanisms of resistance, little is known but many preclinical data raised different hypothesis. Thus, the co-expression of growth factor receptors (EGFR family, IGF-1 R), and the activation of PI3K-Akt pathway, mainly by loss of PTEN function may be responsible for the resistance phenotype. It would be interesting to identify the mechanisms of trastuzumab resistance in breast tumors in order to reverse or prevent it. The characterization of these mechanisms would also provide novel strategies for alternative treatments.