Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.12.2 (MEK)
 18,161 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Bromodomain is a 110 amino acid domain. It is evolutionally conserved and is found in proteins strongly implicated in signal-dependent transcriptional regulation. BRD7 is a novel bromodomain gene and it is downexpressed in nasopharyngeal carcinoma (NPC) biopsies and cell lines; its function is poorly understood. In the present study, tet-on inducible expression system was used to investigate the role of BRD7 in cell growth and cell cycle progression. We found that ectopic expression of BRD7 in NPC cells inhibited cell growth and cell cycle progression from G1 to S. We further performed cell cycle cDNA array to screen potential transcriptional targets of BRD7 in cell cycle. Thirteen important signaling molecules, mainly implicated in ras/MEK/ERK and Rb/E2F pathways, were differentially expressed by induction of BRD7. Moreover, we observed that BRD7 could regulate the promoter activity of E2F3, one of its targets. Taken together, the present study indicated that BRD7 inhibited G1-S progression by transcriptionally regulating some important molecules involved in ras/MEK/ERK and Rb/E2F pathways and suggested that BRD7 may present a promising candidate of NPC trade mark associated tumor suppressor gene.
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PMID:BRD7, a novel bromodomain gene, inhibits G1-S progression by transcriptionally regulating some important molecules involved in ras/MEK/ERK and Rb/E2F pathways. 1513 61

BRD7, a novel bromodomain gene, is identified to be associated with nasopharyngeal carcinoma (NPC). Decreased or loss of expression of BRD7 was detected in NPC biopsies and cell lines. Overexpression of BRD7 could inhibit NPC cell growth and arrest cells in cell cycle by transcriptionally regulating some important molecules involved in ras/MEK/ERK and Rb/E2F pathway, and downregulate the promoter activity of E2F3. In the present study, the subcellular localization of BRD7 was investigated. It was found that BRD7 was mainly localized in nucleus without distinct cell-specific difference between COS7 and HNE1. Furthermore, a functional nuclear localization signal (NLS) sequence ranging from amino acid 65 to 96 was identified and characterized. The NLS is composed of a cluster of four bipartite nuclear targeting sequences, which are tightly linked and extremely overlapped. We found that whether the entire NLS or the four bipartite nuclear targeting sequences could respectively determine the nuclear import of green fluorescent protein (GFP). The most important is that NLS-deleted BRD7 shifted the nuclear localization to be mostly in cytoplasm, and failed or reduced to negatively regulate the expression of cell cycle related molecules, cyclin D1 and E2F3, and cell cycle progression from G1 to S phase. In conclusion, NLS is an essential motif affecting BRD7 nuclear distribution, and the nuclear localization of BRD7 is critical for the expression of cell cycle related molecules and cell biological function.
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PMID:Identification of nuclear localization signal that governs nuclear import of BRD7 and its essential roles in inhibiting cell cycle progression. 1647 62

BRD7 is a novel gene which involved NPC in our lab. Our previous studies showed that BRD7 was expressed at high level in normal nasopharyngeal epithelial tissues, but at low level in nasopharyngeal carcinoma biopsies and cell lines. In these papers, we found that ectopic expression of BRD7 can decrease cell proliferation and capability to form colonies in soft agar. FCM (Flow cytometry) assay indicated that the cell cycle progression from G1 to S phase was inhibited and the expression of cyclinD1 was significantly decreased after being transfected with BRD7 in HNE1 cells (NPC cells). To further investigate the molecular mechanism of BRD7 suppression of NPC cells growth, the cDNA microarray was performed to detect difference in gene expression profile induced by BRD7. The results indicated that 21 genes expression were changed after being transfected with BRD7 and the differentially expressed gene including alpha-catenin, cyclinD1, E2F3 was confirmed by western-blot. Next, we found that even though no obvious changes of the total expression of beta-catenin were observed, the accumulation of beta-catenin in nucleus was blocked. In addition, it was found that the expression of beta-catenin was up-regulated in the complex composed of beta-catenin and alpha-catenin in HNE1 cells induction of BRD7. So, we concluded that over-expression of BRD7 increased the expression of alpha-catenin which "hold" beta-catenin in the complex and inhibited its accumulating in nucleus. At last, we demonstrated the c-jun, p-MEK, and p-ERK1/2 expression were down-regulated, and the Ap-1 promoter activity was inactive after being transfected with BRD7. We also found that over-expression of BRD7 can inactivate the c-jun and p-ERK1/2 after being treated with EGF in HNE1 cells. These results indicated that BRD7 played a negative role in ERK1/2 pathway. Taken together, our present results provide new insights for BRD7 function to inhibit NPC cells growth through negative regulating beta-catenin and ERK1/2 pathways.
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PMID:BRD7 suppresses the growth of Nasopharyngeal Carcinoma cells (HNE1) through negatively regulating beta-catenin and ERK pathways. 1745 18

Nasopharyngeal carcinoma (NPC) is a polygenetic disease. SPLUNC1, UBAP1, BRD7, NAG7, NOR1, NGX6 and LTF genes were found to be tumor suppressor/susceptibility genes in different stages of NPC. SPLUNC1, an early warning molecular diagnosis marker, inhibits the bacteria clone formation, and is an innated immune molecule. SPLUNC1 can negatively regulate the ERK/MAPK signaling transduction pathway to inhibit NPC cell proliferation and induce apoptosis. BRD7, a transcript regulation factor, interacts with BRD2, and promotes apoptosis induced by BRD2. Its promoter is regulated by c-Myc and SP1. BRD7 inhibits NPC cell cycle progression, preventing passage through G0/G1 by suppressing ras/MEK/ERK, Rb/E2F and Wnt signaling pathways. Abnormal activation of BRD7 is crucial to cell cycle turbulence in NPC. NGX6, a metastasis-associated protein, can negative-regulate the EGF/Ras/MAPK signaling transduction pathway, and interacts with ezrin protein to inhibit NPC cell invasion and metastasis. LTF, also a metastasis-associated protein, can negatively regulate MAPK signal transduction pathways, such as JNK2 and ERK, to inhibit NPC cell proliferation and growth. Taken together, it was found that these tumor suppressor/susceptibility genes can regulate key molecules involved in cell signal pathways such as ras/MEK/ERK, Rb/E2F and EGFR ras/MEK/MAPK, and can regulate the expression of some adhesion molecules such as ezrin, nm23 and alpha-catenin. According to functional genomics and signaling transduction pathways, we have described a signaling cross-talk network between the tumor suppressor/susceptibility genes involved in NPC. These tumor suppressor/susceptibility genes may be potential treatment targets for NPC in the future.
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PMID:Signaling Transduction Network Mediated by Tumor Suppressor/Susceptibility Genes in NPC. 1994 42

The research team on the National Key Scientific Program of China: "Transcriptomic regulation and molecular mechanism research of polygenic tumor at different stages" has focused on the field of transcriptomics of 4 common polygenic tumors, including nasopharyngeal carcinoma(NPC), breast cancer, colorectal cancer, and glioma. Extensive laboratory work has been carried out on the expression and regulation of tumor transcriptomics; identification of tumor suppressor/susceptible genes; mechanism of tumor epigenetics including miRNAs, and comparative study of specific gene/protein cluster of tumor transcriptomics and proteomics. Genes including SPLUNC1, LTF, BRD7, NOR1, BRCA1/2, PALB2, AF1Q, SOX17, NGX6, SOX7, and LRRC4 have been identified as the key transcriptional regulation genes during the stage of tumor initiation and invasion. Accordingly,the NPC gene signal regulation network of "SPLUNC1-miR-141-target genes", the breast cancer interaction signal pathway of "miR-193b-uPA",the glioma signal network of "miR-381- LRRC4-MEK/ERK/AKT", and the miRNA-target gene network of colorectal cancer metastasis related gene NGX6 have been thoroughly elucidated. These fruitful Results imply that the changes of key molecules in crucial signal pathway will cause severe dysfunction in signal transduction and gene regulation network in polygenic tumors, indicating that in the category of pathogenesis,these tumors may further classify as the "Disease of gene signal transduction and gene regulation network disorder". The researches have laid solid foundation for revealing the molecular mechanism and transcriptomic regulation of polygenic tumors at different stages.
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PMID:[Transcriptomic regulation and molecular mechanism of polygenic tumor at different stages]. 2187 80

BRD7 (bromodomain 7), also known as celtix-1, was first identified in nasopharyngeal carcinoma (NPC) cells in 2000. BRD7 is a crucial component of both functional p53 and BRCA1 (breast cancer 1, early onset) pathways. Recently, the BRD7 tumor suppressor status has been fully established. Previous studies demonstrated that BRD7 was downregulated in human breast cancer and the downregulation often associates with tumor progression. The expression of BRD7 was downregulated in various cancers, including breast cancer, NPC, gastric cancer, colorectal carcinoma, ovarian cancer, and prostate cancer. Moreover, BRD7 inhibited cancer cell growth and metastasis and promote apoptosis in vitro and in vivo via downregulating AKT pathway. In addition, BRD7 may regulate many signaling pathways including ras-raf-MEK-ERK and RB/E2F. In this review, we provide an overview of current knowledge concerning the role of BRD7 in tumor development and progression. To our knowledge, this is the first review about the role of this novel tumor suppressor gene BRD7in tumor development and progression.
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PMID:BRD7: a novel tumor suppressor gene in different cancers. 2715 66