The cancer genetics and pathology of male breast cancer

Male breast cancer (MBC) is an uncommon and poorly understood disease. Recent molecular studies have shown important differences from female breast cancer which are likely to influence treatment strategies from the current female‐based management towards a more tailored approach. Significantly more MBCs than female breast cancers arise with an underlying germline cancer predisposition, and display a vastly different penetrance compared with females. Furthermore, the genophenotypical association of basal‐like cancer with BRCA1 present in female breast cancer is not observed in male breast cancer. Differences in somatic changes between male and female breast cancer have also been reported, with particular enrichment of PIK3CA mutations and a paucity of TP53 mutations. In general, chromosomal‐based changes, in particular regions of gains, are seen more frequently in male than female breast cancer and methylation is seen less frequently. Clinically, several molecular subtypes with prognostic relevance have been described, including chromosomal complex high and methylation high groups, and subgroups with profiling signatures pertaining to epithelial mesenchymal transition and hormonal therapy insensitivity. As with female breast cancer, attention to male specific multicentre trials based on the individual characteristics are needed, together with establishment of reliable preclinical models to understand more clearly the pathogenesis of male breast cancer and improve the general poor outcome of this disease.     

Diffusion MRI detects early brain microstructure abnormalities in 2‐month‐old 3×Tg‐AD mice

The 3×Tg‐AD mouse is one of the most studied animal models of Alzheimer's disease (AD), and develops both amyloid beta deposits and neurofibrillary tangles in a temporal and spatial pattern that is similar to human AD pathology. Additionally, abnormal myelination patterns with changes in oligodendrocyte and myelin marker expression are reported to be an early pathological feature in this model. Only few diffusion MRI (dMRI) studies have investigated white matter abnormalities in 3×Tg‐AD mice, with inconsistent results. Thus, the goal of this study was to investigate the sensitivity of dMRI to capture brain microstructural alterations in 2‐month‐old 3×Tg‐AD mice. In the fimbria, the fractional anisotropy (FA), kurtosis fractional anisotropy (KFA), and radial kurtosis (K_┴) were found to be significantly lower in 3×Tg‐AD mice than in controls, while the mean diffusivity (MD) and radial diffusivity (D_┴) were found to be elevated. In the fornix, K_┴ was lower for 3×Tg‐AD mice; in the dorsal hippocampus MD and D_┴ were elevated, as were FA, MD, and D_┴ in the ventral hippocampus. These results indicate, for the first time, dMRI changes associated with myelin abnormalities in young 3×Tg‐AD mice, before they develop AD pathology. Morphological quantification of myelin basic protein immunoreactivity in the fimbria was significantly lower in the 3×Tg‐AD mice compared with the age‐matched controls. Our results demonstrate that dMRI is able to detect widespread, significant early brain morphological abnormalities in 2‐month‐old 3×Tg‐AD mice.     

Hypolipidemic activity of a hydroalcoholic extract of Cyperus scariosus Linn. root in guinea pigs fed with a high cholesterol diet

Lipid-lowering and antioxidant activities of a hydroalcoholic extract of Cyperus scariosus Linn. root（HCS） were evaluated in guinea pigs fed with a high cholesterol diet. Serum lipid profile（total cholesterol, triglycerides, LDL-C, VLDL-C, and HDL-C）, atherogenic indices and serum enzymes（ALT, AST, ALP, LDH, and CK-MB） were performed in each group at 0 days and at the end of 60 days. Histological study of liver and kidney was done in groups 1, 2, 5, 6 and 7. The total phenolic and flavonoid content in HCS and its antioxidant activity were evaluated by the DPPH assay. Both doses of HCS decreased serum lipid profile and atherogenic indices（P 〈 0.05）. HCS has lipid lowering, immunosuppressive and antioxidant properties, and mays have value in atherosclerosis prevention. The higher dose of HCS also reduced serum AST, ALP, and LDH levels and rosuvastatin increased AST and ALP levels（P 〈 0.05）. Histology of the liver showed decreased lipid accumulation and improvement in hepatocytes in HCStreated animals. The antioxidant activity of HCS may be responsible for its lipid lowering and cytoprotective action. HCS had significant lipid lowering and antioxidant activity, which; may be due to the phenolic compounds. HCS may be a safe and cost effective alternative to current statin therapy for patients with dyslipidaemia.     

Spectrum of microscopic colitis in a tertiary care centre in India

INTRODUCTION: The incidence of microscopic colitis has recently increased. Although collagenous colitis and lymphocytic colitis are the two main subtypes of microscopic colitis, many patients may not fit into either category and are thus included under the header nonspecific colitis. Of late, the spectrum of microscopic colitis has widened to include minimal change colitis, microscopic colitis not otherwise specified and microscopic colitis with giant cells. There is a lack of information concerning the spectrum of microscopic colitis in Asia. METHOD: In a retrospective analysis, case records of 29 patients diagnosed with microscopic colitis between 1999-2005 were analysed. Drug use parasitic infection and common bacterial infections were excluded. Colonoscopic/ sigmoidoscopic examination was done and multiple colonic mucosal biopsies were stained serially with haematoxylin and eosin for detailed histological examination and Masson trichrome for sub-epithelial collagen band. Based on histological criteria, patients were categorised into five subtypes: collagenous colitis (presence of collagenous thickening of surface epithelium basement membrane > 10 microm), lymphocytic colitis (intra-epithelial lymphocytes more than 20 per 100 colonocytes), minimal change colitis (crypt architectural abnormality in the form of cryptitis and crypt dilatation in the absence of increase in intraepithelial lymphocytes and subepithelial collagenous band), microscopic colitis not otherwise specified (increased inflammatory cell infiltrates in the lamina propria in the absence of other abnormalities) and microscopic colitis with giant cells. RESULTS: Mean age of patients was 38.59 years (range 12-62). Of 29 patients with microscopic colitis, 7 (24.1%), 4 (13.8%), 7 (24.1%) and 11 (37.9%) were classified as collagenous colitis, lymphocytic colitis, minimal change colitis and microscopic colitis not otherwise specified, respectively. None of these patients had giant cells. There was no significant correlation between disease type and clinical manifestations. CONCLUSION: Microscopic colitis has a wide histological spectrum. Cases reported as non-specific colitis, may be categorised into definite subtypes of microscopic colitis.     

Roles of PINK1, mTORC2, and mitochondria in preserving brain tumor-forming stem cells in a noncanonical Notch signaling pathway

The self-renewal versus differentiation choice of Drosophila and mammalian neural stem cells (NSCs) requires Notch (N) signaling. How N regulates NSC behavior is not well understood. Here we show that canonical N signaling cooperates with a noncanonical N signaling pathway to mediate N-directed NSC regulation. In the noncanonical pathway, N interacts with PTEN-induced kinase 1 (PINK1) to influence mitochondrial function, activating mechanistic target of rapamycin complex 2 (mTORC2)/AKT signaling. Importantly, attenuating noncanonical N signaling preferentially impaired the maintenance of Drosophila and human cancer stem cell-like tumor-forming cells. Our results emphasize the importance of mitochondria to N and NSC biology, with important implications for diseases associated with aberrant N signaling.