Figure 1.

Myocyte Enhancer Factor 2C expression in resected human brain metastases derived from breast cancer patients and from glioma patients. Immunofluorescence analysis of myocyte enhancer factor 2C (MEF2C) (purple) and of the epithelial and tumoral marker, pan Cytokeratin (green), in human brain metastases from breast cancer patients, revealed distinct MEF2C labeling patterns that were considered as three different phenotypes: ~100% cells presenting an extranuclear location (P1); ~50% cells presented extranuclear location and ~50% presented overall cell staining (P2); or ~100% cells presenting overall cell staining (P3) (a). Schematic representation of the subcellular MEF2C distribution, according to the considered phenotypes (P1, P2, P3) (b). Semi-quantitative analysis of the percentage of patients presenting each phenotype, regarding the number (c) and the size of the metastases (d), shows the progression from P1 to P3 as the number and size of metastases increase. Double labeling of MEF2C and pan Cytokeratin in brain tissue samples derived from glioma patients as non-breast cancer brain metastases control (e) showing no relevant expression of the protein. Twenty-four cases of BCBM (P1, n = 3; P2, n = 10; P3, n = 11) and ten control cases were studied; ten fields per section and one section per case were analyzed.