Roberto Murgo

Changes in CpG Islands Promoter Methylation Patterns during Ductal Breast Carcinoma Progression

Aberrant promoter methylation of several known or putative tumor suppressor genes occurs frequently during carcinogenesis, and this epigenetic change has been considered as a potential molecular marker for cancer. We examined the methylation status of nine genes (APC, CDH1, CTNNB1, TIMP3, ESR1, GSTP1, MGMT, THBS1, and TMS1), by quantitative methylation specific PCR. Synchronous preinvasive lesions (atypical ductal hyperplasia and/or ductal carcinoma in situ) and invasive ductal breast carcinoma from 52 patients, together with pure lesions from 24 patients and 12 normal tissues paired to tumor and 20 normal breast distant from tumor were analyzed. Aberrant promoter methylation was detected in both preinvasive and invasive lesions for genes APC, CDH1, CTNNB1, TIMP3, ESR1, and GSTP1. However, hierarchical mixed model and Generalized Estimating Equations model analyses showed that only APC, CDH1, and CTNNB1 promoter regions showed a higher frequency and methylation levels in pathologic samples when compared with normal breast. Whereas APC and CTNNB1 did not show differences in methylation levels or frequencies, CDH1 showed higher methylation levels in invasive tumors as compared with preinvasive lesions (P < 0.04, Mann-Whitney test with permutation correction). The analysis of APC, CDH1, and CTNNB1 methylation status was able to distinguish between normal and pathologic samples with a sensitivity of 67% (95% confidence interval, 60-71%) and a specificity of 75% (95% confidence interval, 69-81%). Our data point to the direct involvement of APC, CDH1, and CTNNB1 promoter methylation in the early stages of breast cancer progression and suggest that they may represent a useful tool for the detection of tumor cells in clinical specimens. (Cancer Epidemiol Biomarkers Prev 2009;18(10):2694–700)

Aberrant Keap1 methylation in breast cancer and association with clinicopathological features

Keap1 (Kelch-like ECH-associated protein 1) is an adaptor protein that mediates the ubiquitination/degradation of genes regulating cell survival and apoptosis under oxidative stress conditions. We determined methylation status of the KEAP1 promoter in 102 primary breast cancers, 14 pre-invasive lesions, 38 paired normal breast tissues and 6 normal breast from reductive mammoplasty by quantitative methylation specific PCR (QMSP). Aberrant promoter methylation was detected in 52 out of the 102 primary breast cancer cases (51%) and 10 out of 14 pre-invasive lesions (71%). No mutations of the KEAP1 gene were identified in the 20 breast cancer cases analyzed by fluorescence based direct sequencing. Methylation was more frequent in the subgroup of patients identified as ER positive-HER2 negative tumors (66.7%) as compared with triple-negative breast cancers (35%) (p = 0.05, Chi-square test). The impact of the interactions between Er, PgR, Her2 expression and KEAP1 methylation on mortality was investigated by RECPAM multivariable statistical analysis, identifying four prognostic classes at different mortality risks. Triple-negative breast cancer patients with KEAP1 methylation had higher mortality risk than patients without triple-negative breast cancer (HR = 14.73, 95%CI: 3.65–59.37). Both univariable and multivariable COX regressions analyses showed that KEAP1 methylation was associated with a better progression free survival in patients treated with epirubicin/cyclophosfamide and docetaxel as sequential chemotherapy (HR = 0.082; 95%CI: 0.007–0.934). These results indicate that aberrant promoter methylation of the KEAP1 gene is involved in breast cancerogenesis. In addition, identifying patients with KEAP1 epigenetic abnormalities may contribute to disease progression prediction in breast cancer patients.

Conservative surgery with and without radiotherapy in elderly patients with early-stage breast cancer: a prospective randomised multicentre trial.

Breast conserving therapy (BCT) including postoperative irradiation of the remaining breast tissue is generally accepted as the best treatment for the majority of patients with early-stage breast cancer. The question is whether there is a necessity for irradiating all patients. Between 2001 and 2005, 749 women aged 55-75 years with infiltrating breast carcinoma were randomly assigned to breast conservative surgery, with or without radiotherapy (RT), to evaluate the incidence of in-breast recurrence (IBR). After 5 years of median follow-up, the cumulative incidence of IBR was 2.5% in the surgery-only arm and 0.7% in the surgery plus RT arm. There are no differences in terms of overall survival and distant disease-free survival. The preliminary evaluation suggests that breast irradiation after conservative surgery can be avoided without exposing these patients to an increased risk of distant-disease recurrence. Prolonged follow-up will further clarify the possible risks and late sequelae potentially induced by breast RT.

High RAD51 mRNA expression characterize estrogen receptor‐positive/progesteron receptor‐negative breast cancer and is associated with patient's outcome

Mutations in DNA double‐strand breaks (DSB) repair genes are involved in the pathogenesis of hereditary mammary tumors, it is, however, still unclear whether defects in this pathway may play a role in sporadic breast cancer. In this study, we initially determined mRNA expression of 15 DSB related genes by reverse transcription quantitative polymerase chain reaction in paired normal tissue and cancer specimen from 20 breast cancer cases to classify them into homogeneous clusters. G22P1/ku70, ATR and RAD51 genes were differentially expressed in the three branches recognized by clustering analysis. In particular, a breast cancer subgroup characterized by high RAD51 mRNA levels and estrogen receptor (ER)‐positive/progesteron receptor (PR)‐negative phenotype was identified. This result was confirmed by the analysis of G22P1/ku70, ATR and RAD51 mRNA levels on paired normal and tumor specimens from an extended breast cancer cohort (n = 75). RAD51 mRNA levels were inversely associated with PR status (p = 0.02) and the highest levels were, indeed, detected in ER‐positive/PR‐negative tumors (p = 0.03). RAD51 immunostaining of a tissue microarray confirmed the inverse relationship between high RAD51 expression and negative PR status (p = 0.002), as well as, the association with ER‐positive/PR‐negative phenotype (p = 0.003). Interestingly, the analysis of microarray expression data from 295 breast cancers indicate that RAD51 increased mRNA expression is associated with higher risk of tumor relapse, distant metastases and worst overall survival (p = 0.015, p = 0.009 and p = 0.013 respectively). Our results suggest that RAD51 expression determination could contribute to a better molecular classification of mammary tumors and may represent a novel tool for evaluating postoperative adjuvant therapy for breast cancer patients.

Comparison between real-time quantitative PCR detection of HER2 mRNA copy number in peripheral blood and ELISA of serum HER2 protein for determining HER2 status in breast cancer patients

Background: The development of non-invasive procedure to determine HER2 status may represent a powerful method for monitoring disease progression and response to the treatment. Methods: Serum samples and RNA from peripheral blood were evaluated in 85 breast cancer patients (49 HER2 positive and 36 HER2 negative) and 22 healthy controls. HER2 mRNA levels were measured by real-time quantitative PCR (QPCR) and serum HER2 protein by immunoenzimatic assay (EIA). ROC curve analyses were used to determine the optimal cut off values. Results: A statistically significant difference was detected for both QPCR and EIA in HER2 positive patients as compared with both healthy controls and HER2 negative tumours. QPCR showed a 91% (CI95%: 84%–98%) specificity and a 78% (CI95%: 68%–88%) sensitivity for an optimal cut off value of 4.74. The optimal cut off value for EIA was 22 ng/ml yielding a 95% (CI95%: 90%–100%) specificity and a 59% (CI95%: 48%–70%) sensitivity. The QPCR assay was slightly less specific than EIA in discriminating HER2 positive breast cancers from HER2 negative tumours (78% CI95%: 69%–87% versus 86% CI95%: 79%–93%), but it was more sensitive (76% CI95%: 67%–85% versus 55% CI95%: 44%–66%). Conclusions: Our results indicate that QPCR performs better than EIA in the determination of HER2 status of breast cancer patients and could be useful in monitoring the disease during follow up.

Stepwise analysis of MIR9 loci identifies miR-9-5p to be involved in Oestrogen regulated pathways in breast cancer patients

miR-9 was initially identified as an epigenetically regulated miRNA in tumours, but inconsistent findings have been reported so far. We analysed the expression of miR-9-5p, miR-9-3p, pri-miRs and MIR9 promoters methylation status in 131 breast cancer cases and 12 normal breast tissues (NBTs). The expression of both mature miRs was increased in tumours as compared to NBTs (P < 0.001) and negatively correlated with ER protein expression (P = 0.005 and P = 0.003, for miR-9-3p and miR-9-5p respectively). In addition, miR-9-5p showed a significant negative correlation with PgR (P = 0.002). Consistently, miR-9-5p and miR-9 3p were differentially expressed in the breast cancer subgroups identified by ER and PgR expression and HER2 amplification. No significant correlation between promoter methylation and pri-miRNAs expressions was found either in tumours or in NBTs. In the Luminal breast cancer subtype the expression of miR-9-5p was associated with a worse prognosis in both univariable and multivariable analyses. Ingenuity Pathway Analysis exploring the putative interactions among miR-9-5p/miR-9-3p, ER and PgR upstream and downstream regulators suggested a regulatory loop by which miR-9-5p but not miR-9-3p is induced by steroid hormone receptor and acts within hormone-receptor regulated pathways.

Abstract 3977: Evaluation of miR10b and miR9 expression in breast cancer and correlations with distant metastases development

Proceedings: AACR 106th Annual Meeting 2015; April 18-22, 2015; Philadelphia, PA We have recently demonstrated that the evaluation of miR10b expression relative to its normal counterparts (Relative Expression Ratio, RER) is able to predict patients risk to develop distant metastases. To confirm these results and evaluate whether other microRNAs could be predictive of outcome in breast cancer we evaluated the expression of miR10b and miR9 in paired tumors and apparently normal breast tissues 2 cm distant from tumour (NBT) on an extended cohort (n = 127) with a longer follow up (median 42 months). As control normal breast tissues from 10 healthy subjects (HBT) treated by reductive mammoplasty were analyzed. An increased expression was seen for the miR9 and miR10b in NBT samples as compared with HBT (P<0.01). Whereas the expression of each of the two miRNAs was significantly lower in tumour samples as compared to the NBT specimens with RER value of 0.15 for miR10b (P = 0.001) and 0.59 for miR9 (P = 0.05). However only higher miR10b RERs were associated with distant metastases development in multivariable analysis (HR = 1.12; P = 0.04). Our results confirm the role of miR10b as predictive biomarkers of metastases development in breast cancer. In addition our data suggest a deregulation of miRNAs expression in the normal tissue surrounding tumor as compared to normal breast of healthy individuals. Citation Format: Raffaela Barbano, Barbara Pasculli, Massimiliano Copetti, Andrea Fontana, Michelina Coco, Lorenzo Vitulano, Maria Luana Poeta, Francesca Picardo, Gianfranco Marangi, Roberto Murgo, Luigi Ciuffreda, Vanna Maria Valori, Vanna Maria Valori, Maria Morritti, Evaristo Maiello, Vito Michele Fazio, Paola Parrella. Evaluation of miR10b and miR9 expression in breast cancer and correlations with distant metastases development. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3977. doi:10.1158/1538-7445.AM2015-3977

Abstract 1477: Evaluation of microRNA-10b prognostic significance in a prospective cohort of breast cancer patients

Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Several prognostic factors are currently used to stratify breast cancer patients based on the risk of disease progression. However, even patients classified as at low risk can progress and die for the disease. MicroRNA-10b (miR-10b) has a prominent role in regulating tumor invasion and metastasis by targeting the HOXD10 transcriptional repressor and has been found up-regulated in several tumor types including breast cancer. We evaluated the expression of miR-10b in paired tumor and normal specimens obtained from a prospective cohort of breast cancer patients with at least 36 months follow-up enrolled according to the REMARK guidelines (n=150). RNA quality was measured and only samples with RNA Integrity Number (RIN) ≥7.0 were analyzed. The relative expression of miR-10b in tumor as compared to its normal counterpart (RER) was determined by RT-qPCR. miR-10b RERs were higher in the subgroup of patients with synchronous metastases (n=11, Median 0.25; IQR 0.11-1.02) as compared with patients without metastases (n=90, Median 0.09; IQR 0.04-0.29) (p=0.028). In the subgroup of patients without synchronous metastases (n=90), higher miR-10b RERs were associated with increased risk of disease progression and death in both univariable (HR 4.35, p=0.021 and HR 6.02, p=0.015 respectively) and multivariable (HR 13.37, p<0.001, and HR 15.39, p=0.003 respectively) Cox regression models. The addition of miR-10b RERs to the Nottingham Prognostic Index (NPI) provided an improvement in discrimination power and risk reclassification abilities for the clinical outcomes at 36 months. Survival C-indices significantly increased from 0.849 to 0.889 (p=0.009) for OS and from 0.735 to 0.767 (p=0.050) for DFS. Our results provide evidences that the addition of miR-10b RERs to the prognostic factors used in clinical routine could improve the prediction abilities for both overall mortality and disease progression in breast cancer patients. Citation Format: Paola Parrella, Raffaela Barbano, Barbara Pasculli, Andrea Fontana, Massimiliano Copetti, Vanna Maria Valori, Maria Luana Poeta, Giuseppe Perrone, Michelina Coco, Teresa Balsamo, Fabio Pellegrini, Andrea Onetti Muda, Evaristo Maiello, Roberto Murgo, Vito Michele Fazio. Evaluation of microRNA-10b prognostic significance in a prospective cohort of breast cancer patients. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1477. doi:10.1158/1538-7445.AM2014-1477

Abstract 664: Aberrant KEAP1 promoter methylation is associated with disease progression in breast cancer patients treated with epirubicin/cyclophosfamide and docetaxel chemotherapy.

Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC The KEAP1 (Kelch-like ECH-Associated Protein 1) is an adaptor protein that mediates the ubiquitination/degradation of genes regulating cell survival and apoptosis under oxidative stress conditions. We investigated the possible contribution of KEAP1 genetic and epigenetic abnormalities to development and progression of breast cancer. Methylation status of the KEAP1 promoter was evaluated in 102 primary breast cancers, 14 pre-invasive lesions, 38 paired normal breast tissues and 6 normal breast from reductive mammoplasty by Quantitative Methylation Specific PCR (QMSP). Aberrant promoter methylation was detected in 52 out of the 102 primary breast cancer cases (51%) and 10 out of 14 pre-invasive lesions (71%). No mutations of the KEAP1 gene were identified in the 20 breast cancer cases analyzed by fluorescence based direct sequencing. Methylation was more frequent in the subgroup of patients identified as ER positive-HER2 negative tumors (66.7%) as compared with triple negative breast cancers (35%) (p=0.02, Mann Whitney U-test). Interactions between ER, PR, HER2 expression and KEAP1 methylation on the mortality were investigated by RECPAM multivariable statistical analysis, identifying four prognostic classes at different mortality risks. Triple negative breast cancer patients with KEAP1 methylation had higher mortality risk than patients without triple negative breast cancer (HR=14.73, 95% CI: 3.65-59.37). Both univariable and multivariable COX regression analyses showed that KEAP1 methylation was associated with a better progression free survival in patients treated with epirubicin/cyclophosfamide and docetaxel as sequential chemotherapy (HR=0.096; 95%CI: 0.011-0.832 p=0.03 and HR=0.082 95%CI: 0.007-0.934 P=0.04 respectively). Our data indicate that aberrant promoter methylation of the KEAP1 gene promoter is involved in breast cancerogenesis. In addition identifying patients with KEAP1 epigenetic abnormalities may contribute to disease progression prediction in breast cancer patients. Citation Format: Raffaela Barbano, Lucia Anna Muscarella, Barbara Pasculli, Vanna Maria Valori, Andrea Fontana, Michelina Coco, Annamaria la Torre, Teresa Balsamo, Maria Luana Poeta, Giovanni Francesco Marangi, Evaristo Maiello, Marina Castelvetere, Fabio Pellegrini, Roberto Murgo, Vito Michele Fazio, Paola Parrella. Aberrant KEAP1 promoter methylation is associated with disease progression in breast cancer patients treated with epirubicin/cyclophosfamide and docetaxel chemotherapy. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 664. doi:10.1158/1538-7445.AM2013-664

RAD51 increased expression as a predictor of outcome in patients with breast cancer.

e21106 Background: Mutations in DNA double strand breaks (DSB) repair genes are clearly associated with the pathogenesis of hereditary breast cancer. It is still unclear whether defects in this pathway may play a role in sporadic breast tumours development and progression. The aim of our study was to evaluate whether changes in expression of DSB repair genes is associated with breast cancer clinicopathological characteristics and patients outcome. METHODS We used a previously published breast cancer data set (van de Vijver et al. N Engl J Med 2009) that included clinical and gene expression data for 295 breast cancer cases. Data on local recurrence free survival, distant metasases free survival and overall survival were available for all patients. Reverse transcription quantitative PCR (qPCR) for mRNA determination and immunoistochemestry for protein analysis were used to confirm the association between the relevant genes analyzed and tumour clinicopathological characteristics on two independent data sets. RESULTS We correlated mRNA microarray expression data for 6 DSB repair genes (BRCA1, BRCA2, G22P1/ku70, ATR, RAD51, TP53) involved in key steps of the pathway with patients outcome using a Cox proportional regression model which also included the known breast cancer prognostic markers (ER, PR, Ki67 and HER2). Increased expression of the RAD51 gene was associated with a higher risk of local recurrence (HR 4.82, P=0.015) and development of distant metastases (HR 6.46, P=0.009). Together with other the other prognostic markers, RAD51 high expression was also a predictor of worse overall survival (HR 7.32, P=0.013). The analysis of an independent data set of 75 breast cancers by qPCR demonstrated that increased expression of the RAD51 gene was associated with a subgroup of Luminal A tumours characterized by absence of the progesterone receptor. This latter result was confirmed at protein expression levels by performing immunohistochemical analysis of the RAD51 protein on 58 breast cancer cases represented on a tissues microarray. CONCLUSIONS Our results indicate that increased expression of the RAD51 gene may serve as an indicator of probability of tumour recurrence (local and distant) and overall survival in breast cancer patients.