Publications by authors named "Buddha Gurung"

Chimeric antigen receptor (CAR) T cells have radically improved the treatment of B cell-derived malignancies by targeting CD19. The success has not yet expanded to treat acute myeloid leukemia (AML). We developed a Sequentially Tumor-Selected Antibody and Antigen Retrieval (STAR) system to rapidly isolate multiple nanobodies (Nbs) that preferentially bind AML cells and empower CAR T cells with anti-AML efficacy.

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Protein arginine methyltransferase 5 (PRMT5), a symmetric arginine methyltransferase, regulates cell functions by influencing gene transcription through posttranslational modification of histones and non-histone proteins. PRMT5 interacts with multiple partners including menin, which controls beta cell homeostasis. However, the role of Prmt5 in pancreatic islets, particularly in beta cells, remains unclear.

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Human epidermal growth factor receptor 2 (HER2) is upregulated in a subset of human breast cancers. However, the cancer cells often quickly develop an adaptive response to HER2 kinase inhibitors. We found that an epigenetic pathway involving MLL2 is crucial for growth of HER2(+) cells and MLL2 reduces sensitivity of the cancer cells to a HER2 inhibitor, lapatinib.

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Menin, a protein encoded by the MEN1 gene, is mutated in patients with multiple endocrine neoplasia type 1 (MEN1). Menin acts as a tumor suppressor in endocrine organs while it is also required for transformation of a subgroup of leukemia. The recently solved crystal structure of menin with different binding partners reveals that menin is a key scaffold protein that cross-talks with various partners, including transcription factors, to regulate gene transcription.

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Pancreatic neuroendocrine tumors (PNETs) are rare, indolent tumors that may occur sporadically or develop in association with well-recognized hereditary syndromes, particularly multiple endocrine neoplasia type 1 (MEN-1). We previously demonstrated that the hedgehog (HH) signaling pathway was aberrantly up-regulated in a mouse model that phenocopies the human MEN-1 syndrome, Men1l/l;RipCre, and that inhibition of this pathway suppresses MEN-1 tumor cell proliferation. We hypothesized that the HH signaling pathway is similarly upregulated in human PNETs.

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Multiple endocrine neoplasia type I (MEN1) is an inherited syndrome that includes susceptibility to pancreatic islet hyperplasia. This syndrome results from mutations in the MEN1 gene, which encodes menin protein. Menin interacts with several transcription factors, including JunD, and inhibits their activities.

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Unlabelled: Multiple endocrine neoplasia type 1 (MEN-1), is a familial tumor syndrome resulting from mutations in the tumor suppressor gene menin (MEN1). Menin plays an essential role in both repressing and activating gene expression. However, it is not well understood how menin represses expression of multiple genes.

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Multiple endocrine neoplasia type 1 (MEN1) is an inherited tumor syndrome that includes susceptibility to pancreatic islet tumors. This syndrome results from mutations in the MEN1 gene, encoding menin. Although menin acts as an oncogenic cofactor for mixed lineage leukemia (MLL) fusion protein-mediated histone H3 lysine 4 methylation, the precise basis for how menin suppresses gene expression and proliferation of pancreatic beta cells remains poorly understood.

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Menin acts as contextual a tumor suppressor and a tumor promoter, partly via epigenetic regulation of gene transcription. While menin is phosphorylated, it remains unclear whether wild type menin has other post-translational modifications. Here, we report that menin is SUMOylated by SUMO1 in vivo and in vitro, and the SUMOylation is reduced by a SUMO protease.

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Menin is a tumour suppressor protein whose loss or inactivation causes multiple endocrine neoplasia 1 (MEN1), a hereditary autosomal dominant tumour syndrome that is characterized by tumorigenesis in multiple endocrine organs. Menin interacts with many proteins and is involved in a variety of cellular processes. Menin binds the JUN family transcription factor JUND and inhibits its transcriptional activity.

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A hallmark of diabetes is an absolute or relative reduction in the number of functional β cells. Therapies that could increase the number of endogenous β cells under diabetic conditions would be desirable. Prevalent gene targeting mouse models for assessing β-cell proliferation and diabetes pathogenesis only address whether deletion of a gene prevents the development of diabetes.

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Cyclin D1 elicits transcriptional effects through inactivation of the retinoblastoma protein and direct association with transcriptional regulators. The current work reveals a molecular relationship between cyclin D1/CDK4 kinase and protein arginine methyltransferase 5 (PRMT5), an enzyme associated with histone methylation and transcriptional repression. Primary tumors of a mouse lymphoma model exhibit increased PRMT5 methyltransferase activity and histone arginine methylation.

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Stigmatellin, a Q(P) site inhibitor, inhibits electron transfer from iron-sulfur protein (ISP) to cytochrome c1 in the bc1 complex. Stigmatellin raises the midpoint potential of ISP from 290 mV to 540 mV. The binding of stigmatellin to the fully oxidized complex, oxidized completely by catalytic amounts of cytochrome c oxidase and cytochrome c, results in ISP reduction.

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The destruction of the Rieske iron-sulfur cluster ([2Fe-2S]) in the bc(1) complex by hematoporphyrin-promoted photoinactivation resulted in the complex becoming proton-permeable. To study further the role of this [2Fe-2S] cluster in proton translocation of the bc(1) complex, Rhodobacter sphaeroides mutants expressing His-tagged cytochrome bc(1) complexes with mutations at the histidine ligands of the [2Fe-2S] cluster were generated and characterized. These mutants lacked the [2Fe-2S] cluster and possessed no bc(1) activity.

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