Male breast cancer: immunohistochemical subtypes and clinical outcome characterization.

AIM: The aim of this study was to assess the molecular subtype profiles of male breast cancer (MBC) and subsequent clinical outcome using a validated 6-marker immunohistochemical panel. METHODS: A total of 43 cases of MBC were examined retrospectively using a semiquantitative immunohistochemical analysis of estrogen receptor (ER), progesterone receptor (PR), Ki-67, human epidermal growth factor receptor 2 (Her2), epidermal growth factor receptor and cytokeratin 5/6. Patients were classified into the following categories: luminal A, luminal B, Her2-positive or basal-like subtypes. RESULTS: The median age of patients was 63 years (r: 32-89). The predominant histology was invasive ductal carcinoma (91%). Only 1 patient had advanced breast cancer at diagnosis. Ninety-three percent were ER-positive and 84% were PR-positive. Two patients had tumors that were ER- and PR-negative. The distribution of tumor molecular subtypes was 19 (44%) luminal A, 22 (51%) luminal B and 2 (5%) basal-like. The Her2-positive tumor subtype was not identified. The clinicopathological characteristics did not differ significantly between tumor subtypes A and B. There were no significant differences in 6-year disease-free survival (74 vs. 82%, p = 0.77) or overall survival (74 vs. 82%, p = 0.69) between luminal A and luminal B subtypes, respectively. CONCLUSION: The most common subtypes in our cohort of MBC were luminal B followed by luminal A, and no differences were found between both tumor subtypes in terms of clinicopathologic characteristics and patient outcome.

Gene pathways associated with mitochondrial function, oxidative stress and telomere length are differentially expressed in the liver of rats fed lifelong on virgin olive, sunflower or fish oils.

This study investigates the effect of lifelong intake of different fat sources rich in monounsaturated (virgin olive oil), n6 polyunsaturated (sunflower oil) or n3 polyunsaturated (fish oil) fatty acids in the aged liver. Male Wistar rats fed lifelong on diets differing in the fat source were killed at 6 and at 24 months of age. Liver histopathology, mitochondrial ultrastructure, biogenesis, oxidative stress, mitochondrial electron transport chain, relative telomere length and gene expression profiles were studied. Aging led to lipid accumulation in the liver. Virgin olive oil led to the lowest oxidation and ultrastructural alterations. Sunflower oil induced fibrosis, ultrastructural alterations and high oxidation. Fish oil intensified oxidation associated with age, lowered electron transport chain activity and enhanced the relative telomere length. Gene expression changes associated with age in animals fed virgin olive oil and fish oil were related mostly to mitochondrial function and oxidative stress pathways, followed by cell cycle and telomere length control. Sunflower oil avoided gene expression changes related to age. According to the results, virgin olive oil might be considered the dietary fat source that best preserves the liver during the aging process.

Triple negative breast cancer subtypes and pathologic complete response rate to neoadjuvant chemotherapy.

Triple negative breast cancer (TNBC) is a heterogeneous disease with distinct molecular subtypes that differentially respond to chemotherapy and targeted agents. The purpose of this study is to explore the clinical relevance of Lehmann TNBC subtypes by identifying any differences in response to neoadjuvant chemotherapy among them. We determined Lehmann subtypes by gene expression profiling in paraffined pre-treatment tumor biopsies from 125 TNBC patients treated with neoadjuvant anthracyclines and/or taxanes +/- carboplatin. We explored the clinicopathological characteristics of Lehmann subtypes and their association with the pathologic complete response (pCR) to different treatments. The global pCR rate was 37%, and it was unevenly distributed within Lehmann's subtypes. Basal-like 1 (BL1) tumors exhibited the highest pCR to carboplatin containing regimens (80% vs 23%, p=0.027) and were the most proliferative (Ki-67>50% of 88.2% vs. 63.7%, p=0.02). Luminal-androgen receptor (LAR) patients achieved the lowest pCR to all treatments (14.3% vs 42.7%, p=0.045 when excluding mesenchymal stem-like (MSL) samples) and were the group with the lowest proliferation (Ki-67≤50% of 71% vs 27%, p=0.002). In our cohort, only tumors with LAR phenotype presented non-basal-like intrinsic subtypes (HER2-enriched and luminal A). TNBC patients present tumors with a high genetic diversity ranging from highly proliferative tumors, likely responsive to platinum-based therapies, to a subset of chemoresistant tumors with low proliferation and luminal characteristics.