Detection of the First Gross CDC73 Germline Deletion in an HPT-JT Syndrome Family
GENES CHROMOSOMES & CANCER
Authors: Cascon, Alberto; Vazquez Huarte-Mendicoa, Carlos; Javier Leandro-Garcia, L.; Leton, Rocio; Suela, Javier; Santana, Alfredo; Boronat Costa, Mauro; Comino-Mendez, Inaki; Landa, Inigo; Sanchez, Lydia; Rodriguez-Antona, Cristina; Cigudosa, Juan C.; Robledo, Mercedes
Abstract
Hereditary primary hyperparathyroidism (HPT) may develop as a solitary endocrinopathy (FIHP) or as part of multiple endocrine neoplasia Type I, multiple endocrine neoplasia Type 2A, or hereditary HPT-jaw tumor syndrome. Inactivating germline mutations of the tumor suppressor gene CDC73 account for 14 and 50% of all FIHP and HPT-JT patients, respectively, and have also been found in almost 20% of apparently sporadic parathyroid carcinoma patients. Although more than 60 independent germline mutations have been described, to date no rearrangement affecting the CDC73 locus has been identified. By means of multiplex-PCR we found a large germline deletion affecting the whole gene in a two-generation HPT-JT family. Subsequently array-CGH and specific PCR analysis determined that the mutation spanned similar to 547 kb, and included four additional genes: TROVE2, GLRX2, B3GALT2, and UCHL5. Although no clear mutation-specific phenotype was found associated to the presence of the mutation, further studies are needed to assess whether the loss of the neighboring genes could modify the phenotype of carriers. There was complete absence of nuclear staining in the two HPT-JT-related tumors available. The finding of the first rearrangement affecting the CDC73 gene warrants screening for this tumor suppressor gene inactivation mechanism not only in high-risk CDC73 point mutation-negative HPT-JT families, but also in FIHP patients. (C) 2011 Wiley-Liss, Inc.
Proteomic screening and identification of microRNA-128 targets in glioma cells
PROTEOMICS
Authors: Yang, Bin; Wang, Shan; Zeng, Jiawei; Zhang, Yu; Ruan, Xiangbin; Han, Wei; Yin, Bin; Yuan, Jiangang; Qiang, Boqin; Ying, Wantao; Qian, Xiaohong; Peng, Xiaozhong
Abstract
Brain-enriched miR-128 is repressed in glioma cells, and could inhibit the proliferation of gliomas by targeting genes such as E2F3a and BMI1. To identify more targets of miR-128 in glioblastoma multiforme, the pulse stable isotope labeling with amino acids in cell culture (pSILAC) technique was used to test its impact on whole protein synthesis in T98G glioma cells. We successfully identified 1897 proteins, of which 1459 proteins were quantified. Among them, 133 proteins were downregulated after the overexpression of miR-128. Through predictions using various bioinformatics tools, 13 candidate target genes were chosen. A luciferase assay validated that 11 of 13 selected genes were potential targets of miR-128, and a mutagenesis experiment confirmed CBFB, CORO1C, GLTP, HnRNPF, and TROVE2 as the target genes. Moreover, we observed that the expression of CORO1C, TROVE2, and HnRNPF were higher in glioma cell lines compared to normal brain tissues and presented a tendency toward downregulation after overexpression of miR-128 in T98G cells. Furthermore, we have validated that CORO1C, TROVE2, and HnRNPF could inhibit glioma cell proliferation. In sum, our data showed that the integration of pSILAC and bioinformatics analysis was an efficient method for seeking the targets of miRNAs, and plentiful targets of miR-128 were screened and laid the foundation for research into the miR-128 regulation network.