MED12 Alterations in Both Human Benign and Malignant Uterine Soft Tissue Tumors

The relationship between benign uterine leiomyomas and their malignant counterparts, i.e. leiomyosarcomas and smooth muscle tumors of uncertain malignant potential (STUMP), is still poorly understood. The idea that a leiomyosarcoma could derive from a leiomyoma is still controversial. Recently MED12 mutations have been reported in uterine leiomyomas. In this study we asked whether such mutations could also be involved in leiomyosarcomas and STUMP oncogenesis. For this purpose we examined 33 uterine mesenchymal tumors by sequencing the hot-spot mutation region of MED12. We determined that MED12 is altered in 66.6% of typical leiomyomas as previously reported but also in 11% of STUMP and 20% of leiomyosarcomas. The mutated allele is predominantly expressed in leiomyomas and STUMP. Interestingly all classical leiomyomas exhibit MED12 protein expression while 40% of atypical leiomyomas, 50% of STUMP and 80% of leiomyosarcomas (among them the two mutated ones) do not express MED12. All these tumors without protein expression exhibit complex genomic profiles. No mutations and no expression loss were identified in an additional series of 38 non-uterine leiomyosarcomas. MED12 mutations are not exclusive to leiomyomas but seem to be specific to uterine malignancies. A previous study has suggested that MED12 mutations in leiomyomas could lead to Wnt/β-catenin pathway activation however our immunohistochemistry results show that there is no association between MED12 status and β-catenin nuclear/cytoplasmic localization. Collectively, our results show that subgroups of benign and malignant tumors share a common genetics. We propose here that MED12 alterations could be implicated in the development of smooth muscle tumor and that its expression could be inhibited in malignant tumors

History from Things: Indigenous Objects and Colonial Latin America

The article discusses the themes of absence and resistance in the history of colonial Latin America. Historians have discovered evidence of indigenous historical agency by exploring acts of resistance. While teaching history, the method that involves pushing beyond traditional questions of aesthetic effect is suggested

Of Copies, Casts, and Codices: Mexico on Display in 1892

In the fall of 1892, to honor the 400th anniversary of Columbus\u27s voyage across the Atlantic, the Exposición Histórico-Americana opened its doors in Madrid. Thousands of visitors came to be awed and edified by all the known portraits depicting Columbus, feather paintings made by Christianized Aztecs, mineralogical specimens, Quimbaya gold figurines, Amerindian skulls and mummies, and even a model of a Viking ship. In a spacious structure on the Paseo de Recoletos (that today houses both the Biblioteca Nacional and the Museo Arqueológico), works from nearly twenty European and American nations were carefully arranged to offer viewers, most of them Madrileños and European tourists, an eclectic and rich visual encounter with the New World and its culture. --first paragrap