Role of epigenetics in relaying the effects of exercise to our bodies

ADVOCATE, Volume 22/ Issue 2 Summer 2015 6 Smooth muscle differentiation classification as a tool for select pleomorphic sarcomas The clinical relevance of accurately diagnosing pleomorphic sarcomas has been shown, especially in cases of undifferentiated pleomorphic sarcomas with myogenic differentiation, which appear significantly more aggressive. To establish a new smooth muscle differentiation classification and to test its prognostic value, 412 sarcomas with complex genetics were examined by immunohistochemistry using four smooth muscle markers calponin, h-caldesmon, transgelin, and smooth muscle actin. First, two tumor categories were defined: tumors with positivity for all four markers and tumors with no or incomplete phenotypes. Multivariate analysis demonstrated that this classification method exhibited the strongest prognostic value compared with other prognostic factors, including histological classification. Second, the incomplete or no smooth muscle phenotype tumor group was divided into subgroups by summing for each tumor the labeling intensities of all four markers. Therefore, a subgroup of tumors with an incomplete but strong smooth muscle differentiation phenotype presenting an intermediate metastatic risk was identified. The authors’ results collectively show that the smooth muscle differentiation classification method may be a useful diagnostic tool and a relevant prognostic tool for undifferentiated pleomorphic sarcomas. Perot G, Mendiboure J, Brouste V, et al. Smooth muscle differentiation identifies two classes of poorly differentiated pleomorphic sarcomas with distinct outcome. Mod Pathol. 2014; 27:840-850 ❖