Céline Charon-Barra

Hypermethylator Phenotype in Sporadic Colon Cancer: Study on a Population-Based Series of 582 Cases

The CpG island methylator phenotype (CIMP) is a distinct phenotype in colorectal cancer, associated with specific clinical, pathologic, and molecular features. However, most of the studies stratified methylation according to two subgroups (CIMP-High versus No-CIMP/CIMP-Low). In our study, we defined three different subgroups of methylation (No-CIMP, CIMP-Low, and CIMP-High) and evaluated the prognostic significance of methylation status on a population-based series of sporadic colon cancers. A total of 582 colon adenocarcinomas were evaluated using methylation-specific PCR for 5 markers (hMLH1, P16, MINT1, MINT2, and MINT31). No-CIMP status was defined as no methylated locus, CIMP-Low status as one to three methylated loci, and CIMP-High status as four or five methylated loci. Clinicopathologic and molecular characteristics were correlated to the methylation status. Crude and relative survival was compared according to methylation status. In the microsatellite-stable (MSS) group, CIMP-High was significantly associated with proximal location (P = 0.011) and BRAF mutation (P < 0.001). KRAS mutations were more associated with CIMP-High and CIMP-Low status (P = 0.008). A shorter 5-year survival was observed in MSS cancer patients with CIMP-Low or CIMP-High status. These results remained significant in multivariate analysis adjusted for age, stage, and BRAF and KRAS mutational status [CIMP-Low: hazard ratio (HR), 1.85; 95% confidence interval (95% CI), 1.37-2.51; CIMP-High, HR, 2.90; 95% CI, 1.53-5.49 compared with No-CIMP]. Within the high-level microsatellite instability group, no difference in survival was observed between the different CIMP groups. Our results show the interest of defining three subgroups of patients according to their methylation status (No-CIMP/CIMP-Low/CIMP-High). Methylation is an independent prognostic factor in MSS colon cancer.

Identification of biomarkers including 18FDG-PET/CT for early prediction of response to neoadjuvant chemotherapy in Triple Negative Breast Cancer

Purpose: To investigate the value of the metabolic tumor response assessed with 18F-fluorodeoxyglucose positron emission tomography (FDG-PET), compared with clinicobiologic markers to predict pathologic complete response (pCR) to neoadjuvant chemotherapy (NAC) in women with triple-negative breast cancer (TNBC). Experimental Design: Fifty consecutive women with TNBC and an indication for NAC were prospectively included. Different pretreatment clinical, biologic, and pathologic biomarkers, including SBR grade, the Ki-67 proliferation index, androgen receptor expression, EGF receptor (EGFR), and cytokeratin 5/6 staining, were assessed. Tumor glucose metabolism at baseline and its change after the first cycle of NAC (ΔSUVmax) were assessed using FDG-PET. Results: The pCR rate was 42%. High Ki-67 proliferation index (P = 0.016), negative EGFR status (P = 0.042), and high ΔSUVmax (P = 0.002) were significantly associated with pCR. In multivariate logistic regression, both negative EGFR status (OR, 6.4; P = 0.043) and high ΔSUVmax (OR, 7.1; P = 0.014) were independent predictors of pCR. Using a threshold at −50%, tumor ΔSUVmax predicted pCR with a negative, a positive predictive value, and an accuracy of 79%, 70%, and 75%, respectively. Combining a low ΔSUVmax and positive EGFR status could predict non-pCR with an accuracy of 92%. Conclusions: It is important to define the chemosensitivity of TNBC to NAC early. Combining EGFR status and the metabolic response assessed with FDG-PET can help the physician to early predict the probability of achieving pCR or not. Given these results, the interest of response-guided tailoring of the chemotherapy might be tested in multicenter trials. Clin Cancer Res; 21(24); 5460–8. ©2015 AACR.

Detection of plasma cells, C4d deposits and donor-specific antibodies on sequential graft biopsies of renal transplant recipients with chronic dysfunction

BACKGROUND In order to look for a relationship between humoral mechanisms of rejection and chronic allograft dysfunction, plasma cells, C4d deposits and donor-specific antibodies (DSA) were simultaneously sought on serial biopsies of kidney allograft recipients. PATIENTS AND METHODS Ten recipients with chronic dysfunction (G1) and 8 recipients with long-term normal graft function (G2) were included. Biopsies and serums were sampled at early graft dysfunction (T1), between 8months and 2years (T2) and after the third year following transplantation (T3). RESULTS In G1, plasma cells represented 12.3% (T1), 8.2% (T2) and 14.1% (T3) of mononuclear cells. The mean percentage of plasma cells was 11.6% in G1 versus 0.4% in G2 (p<0.05). A progressive rise in C4d deposits was seen in G1, from 25% at T1 to 80% at T3. Donor-specific antibodies were identified in at least one serum sample of 60% of the patients in G1 and 12.5% of the patients in G2 (p=0.012), whereas donor-specific antibodies were eluted from at least one biopsy of 50% of the patients in G1 and 12.5% of the patients in G2 (p=0.03). In G1, C4d deposits were significantly associated with plasma cells (p=0.0012) and anti-HLA Abs in serum samples and/or eluates (p=0.026). CONCLUSION This study shows that plasma cells, DSA and C4d are associated in renal transplants developing chronic rejection.

Coexpression of androgen receptor and FOXA1 in nonmetastatic triple-negative breast cancer: ancillary study from PACS08 trial.

AIM Microarray studies identified a subgroup of molecular apocrine tumors (estrogen receptor [ER] negative/androgen receptor [AR] positive) that express luminal genes including FOXA1. FOXA1 may direct AR to sites normally occupied by ER in luminal tumors, inducing an estrogen-like gene program that stimulated proliferation. MATERIALS & METHODS Expression of AR and FOXA1 was evaluated by immunohistochemistry in 592 patients with nonmetastatic triple-negative breast cancer (TNBC). RESULTS Coexpression of AR and FOXA1 was found in 15.2% of patients. These tumors were more frequently lobular, found in older patients and exhibited a lower nuclear grade and a greater degree of node involvement. They less often exhibited lymphocytic infiltrate, pushing margins, syncytial architecture, central fibrosis or necrosis. CONCLUSION TNBC with coexpression of AR and FOXA1 seems to behave like luminal tumors with a morphological profile distinct from other TNBC. These biomarkers could be useful to identify a subgroup of TNBC and could have future therapeutic implications.

Survivin-3B Potentiates Immune Escape in Cancer but Also Inhibits the Toxicity of Cancer Chemotherapy

Dysregulation in patterns of alternative RNA splicing in cancer cells is emerging as a significant factor in cancer pathophysiology. In this study, we investigated the little known alternative splice isoform survivin-3B (S-3B) that is overexpressed in a tumor-specific manner. Ectopic overexpression of S-3B drove tumorigenesis by facilitating immune escape in a manner associated with resistance to immune cell toxicity. This resistance was mediated by interaction of S-3B with procaspase-8, inhibiting death-inducing signaling complex formation in response to Fas/Fas ligand interaction. We found that S-3B overexpression also mediated resistance to cancer chemotherapy, in this case through interactions with procaspase-6. S-3B binding to procaspase-6 inhibited its activation despite mitochondrial depolarization and caspase-3 activation. When combined with chemotherapy, S-3B targeting in vivo elicited a nearly eradication of tumors. Mechanistic investigations identified a previously unrecognized 7-amino acid region as responsible for the procancerous properties of survivin proteins. Taken together, our results defined S-3B as an important functional actor in tumor formation and treatment resistance.

Prognostic value of androgen receptor and FOXA1 co-expression in non-metastatic triple negative breast cancer and correlation with other biomarkers

BackgroundIn luminal androgen receptor (AR) tumours, FOXA1 may direct AR to sites occupied by ER in luminal tumours, thus stimulating proliferation.MethodsAR and FOXA1 expression were evaluated by immunohistochemistry in 333 non-metastatic triple-negative breast cancers (TNBC). Positivity threshold was set at ≥ 1% staining. Lymphocytic infiltration, PD-L1expression, PIK3CA mutations, PTEN defects and BRCA1 promoter methylation were assessed.ResultsAR + /FOXA1 + tumours (42.4%) were more frequently: found in older patients, lobular, of lower nuclear grade, with more frequently PIK3CA mutations; exhibited less frequently BRCA1 promoter methylation, defects of PTEN and PD-L1 expression than others. Recurrence-free and overall survivals were significantly lower for AR + /FOXA1 + TNBC (median follow-up: 7.8 years).ConclusionsAR + /FOXA1 + expression defines a luminal-like TNBC subgroup affected with a worse outcome compared to other TNBC and a higher risk of late recurrences. This subgroup appears enriched in PIK3CA mutations, suggesting a role for PI3K inhibitors in this subgroup.

Acute and delayed toxicity of gemcitabine administered during isolated lung perfusion: a preclinical dose-escalation study in pigs

OBJECTIVES Colorectal cancer is the third most commonly diagnosed cancer worldwide, with up to 25% of patients presenting with metastases at the time of diagnosis. Despite pulmonary metastasectomy many patients go on to develop pulmonary recurrence, which might be linked to the presence of lung micrometastases. In this setting, the adjuvant administration of high-dose chemotherapy by isolated lung perfusion (ILP) has shown encouraging results. However, the tolerance to and efficacy of modern gemcitabine (GEM)-based chemotherapy regimens during adjuvant ILP remain unknown. We conducted a dose-escalating preclinical study to evaluate the immediate and delayed toxicity of GEM in a pig model to define dose-limiting toxicity (DLT) and maximum tolerated concentration. METHODS Twenty-three pigs were given increasing concentrations of GEM during ILP, and were awakened at the end of the procedure. The concentrations of GEM were 40, 80, 160, 320, 640 and 1280 µg/ml. Serum and lung samples were taken to measure GEM concentrations. Pulmonary damage was evaluated by histological examination and cleaved caspase-3 detection. Immediate and delayed (1 month) toxicity were recorded. RESULTS All of the animals underwent successful ILP with GEM. No systemic leak was observed. The three pigs that received a concentration of GEM of 1280 µg/ml died of hypoxia after lung recirculation at the end of the procedure. Eleven pigs survived for 1 month. Major lung toxicity was observed for the concentration of GEM of 640 µg/ml, both at the end of the procedure and after 1 month. DLT was defined at the concentration of 640 µg/ml and the maximum tolerated dose (MTD) was defined at the concentration of 320 µg/ml. CONCLUSIONS ILP with GEM is a safe and reproducible technique in this large-animal model, which includes 1 month of survival. The MTD in this pig model was a concentration of GEM of 320 µg/ml.

Abstract P5-05-02: Expression of androgen receptor and FOXA1 in non metastatic poor prognosis HER2- negative breast cancer: Ancillary study from UNICANCER-PACS08 multicenter trial

Background Androgen receptor (AR) is expressed in 70-90% of estrogen receptor (ER) positive breast cancer but its expression in triple negative (TN) tumors is less frequent and extremely variable across studies, probably due to their heterogeneity. FOXA1 is essential for expression of 50% of ER-related genes and is a good prognostic factor in luminal tumors. Microarray studies identified the subgroup of molecular apocrine tumors (ER-, AR+) expressing luminal genes including FOXA1, for which pre-clinical data suggested that FOXA1 may direct AR to sites normally occupied by ER in luminal tumors, inducing an estrogen-like gene program stimulating proliferation. We aimed at precising AR expression-associated profiles among a prospective collection of HER2-negative, progesterone receptor (PR)-negative breast tumors. Patients and methods Expression of AR and FOXA1 were evaluated by immunohistochemistry on tissue microarrays in 762 patients enrolled in the PACS08 adjuvant randomized trial evaluating ixabepilone in patients with TN or ER+, PR-, HER2- poor prognosis breast cancer. Two observers evaluated independently AR and FOXA1 expressions. A tumor was considered as positive when at least 10% of the tumor cells were stained. Kappa coefficients were used to assess the agreement between the 2 observers. Categorical clinico-pathological characteristics according to AR and/or FOXA1 expression were compared using Chi-square test or Fisher9s exact test when appropriate. Student9s t-test and the One way Anova were used to compare continuous variable across patient groups. Results Evaluation of AR and FOXA1 expressions were highly reproducible with inter-observer Kappa coefficients of 0.96 and 0.90 respectively. Both AR and FOXA1 expressions were available in 592 cases, 38% of which were AR+ and 30% FOXA1+. The majority (59.6%) of the tumors was AR-/FOXA1-, 27.9% were AR+/FOXA1+. AR+/FOXA1+ tumors were more frequently: found in older patients (p Among 487 TN and 136 ER+ tumors, 25.9% and 80.9% respectively were AR+. Among 468 TN and 134 ER+ tumors, 16.4% and 77.6% respectively were FOXA1+. In TN patients, both AR and FOXA1 expressions were available in 460 cases, 72.8% of which were AR-/FOXA1- and 15.2% AR+/FOXA1+. FOXA1+ tumors were more frequently of lobular histology (p = 0.02). AR+/FOXA1+ tumors were more frequently found in older patients (p = 0.0002), had lower nuclear grade (p The follow-up is currently too short to report the prognostic value of these markers. Conclusions ER+ tumors were mainly AR+/FOXA1+. In this large series, 25.9% of TN tumors were AR+. AR+/FOXA1+ tumors represent 15.2% of TN tumors and seem to behave like luminal tumors (older patients, lobular histology, lower nuclear grade, node involvement). Anti-androgen therapies are currently under investigation in TN breast cancer; these results stimulate also consideration of FOXA1 as potential therapeutic target. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-05-02.