Suchergebnisse

Triple-Negative Breast Cancer (TNBC) has poor prognosis and no approved targeted therapy. We previously showed that the enzyme fatty acid synthase (FASN) was largely expressed in a small TNBC patients' cohort and its inhibition synergized with cetuximab in TNBC preclinical mouse models. Here, we evaluated FASN and EGFR expression in a cohort of TNBC patients and we study their prognostic role and their association with clinico-histopathological features, intrinsic TNBC subtypes and survival. FASN, EGFR, CK5/6 and vimentin expression were retrospective evaluated by Immunohistochemistry in 100 primary TNBC tumors. FASN expression was classified into high and low FASN groups. EGFR, CK5/6 and vimentin expression were used in TNBC intrinsic subtypes classification. FASN was expressed in most of the TNBC patients but did not correlate with overall survival or disease-free survival in this cohort. High FASN group was significantly associated with positive node status. FASN expression was significantly higher in Basal-Like patients than in Mesenchymal-Like ones. EGFR expression was positive in 50% of the tumors, and those patients showed poorer DFS. Altogether, our findings provide a rationale for further investigation the prognostic role of FASN and EGFR expression in a larger cohort of TNBC patients ; This work was supported in part by the Spanish Instituto de Salud Carlos III (ISCIII) (FIS PI11/00692; TP and PI14/00329; TP), Fundación Ramón Areces (TP), the Catalonian Government (2014SGR00868) and the University of Girona (MPCUdG2016/036 and predoctoral grant to AG-P)

Constitutional MLH1 methylation (epimutation) is a rare cause of Lynch syndrome. Low-level methylation (≤ 10%) has occasionally been described. This study aimed to identify low-level constitutional MLH1 epimutations and determine its causal role in patients with MLH1-hypermethylated colorectal cancer. Eighteen patients with MLH1-hypermethylated colorectal tumors in whom MLH1 methylation was previously undetected in blood by methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) were screened for MLH1 methylation using highly sensitive MS-melting curve analysis (MS-MCA). Constitutional methylation was characterized by different approaches. MS-MCA identified one patient (5.6%) with low-level MLH1 methylation (~ 1%) in blood and other normal tissues, which was confirmed by clonal bisulfite sequencing in blood. The patient had developed three clonally related gastrointestinal MLH1-methylated tumor lesions at 22, 24, and 25 years of age. The methylated region in normal tissues overlapped with that reported for other carriers of constitutional MLH1 epimutations. Low-level MLH1 methylation and reduced allelic expression were linked to the same genetic haplotype, whereas the opposite allele was lost in patient's tumors. Mutation screening of MLH1 and other hereditary cancer genes was negative. Herein, a highly sensitive MS-MCA-based approach has demonstrated its utility for the identification of low-level constitutional MLH1 epigenetic mosaicism. The eventual identification and characterization of additional cases will be critical to ascertain the cancer risks associated with constitutional MLH1 epigenetic mosaicism ; This work was funded by the Spanish Ministry of Economy and Competitiveness, which is part of Agencia Estatal de Investigación (AEI), and co-funded by FEDER funds—a way to build Europe—(grant SAF2012-33636 and SAF2015-68016-R), CIBERONC, the Spanish Association Against Cancer (080253), and the Government of Catalonia (grants 2014SGR338, 2017SGR1282, and PERIS SLT002/16/0037). ED ...