Peranan Modal Dari Keluarga Pada 3 UKM di Bandung

Usaha kecil dan menengah menjadi bagian terbesar dari dunia usaha di Indonesia ,  yang telah  terbukti mampu bertahan selama masa krisis, tahun 1997-1998 dan tahun 2008. Usaha skala kecil dan menengah ini (UKM) memiliki peran penting terhadap perkembangan ekonomi, menyerap jumlah tenaga kerja yang banyak memberikan kontribusi terhadap GDP. Ada suatu fakta yang belum cukup  dipahami , bahwa berdirinya usaha skala kecil dan menengah umumnya dimulai dengan melibatkan anggota keluarga atau tidak langsung  mendapat dukungan dan bantuan keluarga . Penelitian ini difokuskan untuk menemukan   peran  modal  yang diberikan oleh keluarga pada saat pendirian usaha dan dalam perkembangannya,  baik modal yang  berupa uang dan finansial (harta tetap atau harta lancar), maupun yang bersifat nilai-nilai (family capital), dan emosi-waktu-perhatian (psychological capital) , dsb . Penelitian dilaksanakan dengan metode kualitatif yakni Multi Case Studies. Tiga UKM  di Bandung  dipilih sebagai obyek penelitian.  Teknik wawancara dan observasi digunakan saling melengkapi   . Hasil transkrip wawancara dikategorisasi (coding) sesuai tema penelitian. Teori modal Bourdieu (1996) digunakan untuk menganalisis dan untuk mendapatkan pemaknaan dari temuan. Temuan menunjukkan bahwa modal ekonomi bukanlah satu-satunya faktor yang berperan dalam memulai dan mengembangkan usaha dalam 3 kasus ini.  Ada  modal yang lain yaitu modal budaya dan modal sosial yang punya peran penting  terhadap awal dan  kelangsungan usaha. Modal simbolik dapat  dibangun dari   modal budaya  sejalan dengan berjalannya usaha dalam  jangka waktu yang cukup   lama. Kata-kata Kunci : modal ekonomi, modal budaya, modal sosial, modal simboli

Autocrine Activation of the MET Receptor Tyrosine Kinase in Acute Myeloid Leukemia

Although the treatment of acute myeloid leukemia (AML) has improved significantly, more than half of all patients develop disease that is refractory to intensive chemotherapy. Functional genomics approaches offer a means to discover specific molecules mediating aberrant growth and survival of cancer cells. Thus, using a loss-of-function RNA interference genomic screen, we identified aberrant expression of the hepatocyte growth factor (HGF) as a critical factor in AML pathogenesis. We found HGF expression leading to autocrine activation of its receptor tyrosine kinase, MET, in nearly half of the AML cell lines and clinical samples studied. Genetic depletion of HGF or MET potently inhibited the growth and survival of HGF-expressing AML cells. However, leukemic cells treated with the specific MET kinase inhibitor crizotinib developed resistance due to compensatory upregulation of HGF expression, leading to restoration of MET signaling. In cases of AML where MET is coactivated with other tyrosine kinases, such as fibroblast growth factor receptor 1 (FGFR1), concomitant inhibition of FGFR1 and MET blocked compensatory HGF upregulation, resulting in sustained logarithmic cell kill both in vitro and in xenograft models in vivo. Our results demonstrate widespread dependence of AML cells on autocrine activation of MET, as well as the importance of compensatory upregulation of HGF expression in maintaining leukemogenic signaling by this receptor. We anticipate that these findings will lead to the design of additional strategies to block adaptive cellular responses that drive compensatory ligand expression as an essential component of the targeted inhibition of oncogenic receptors in human cancers

A High-Efficiency Cellular Extraction System for Biological Proteomics

Recent developments in quantitative high-resolution mass spectrometry have led to significant improvements in the sensitivity and specificity of biochemical analyses of cellular reactions, protein-protein interactions, and small molecule drug discovery. These approaches depend on cellular proteome extraction that preserves native protein activities. Here, we systematically analyzed mechanical methods of cell lysis and physical protein extraction to identify those that maximize the extraction of cellular proteins while minimizing their denaturation. Cells were mechanically disrupted using Potter-Elvehjem homogenization, probe or adaptive focused acoustic sonication, and in the presence of various detergents, including polyoxyethylene ethers and esters, glycosides, and zwitterions. Using fluorescence spectroscopy, biochemical assays, and mass spectrometry proteomics, we identified the combination of adaptive focused acoustic (AFA) sonication in the presence of binary poloxamer-based mixture of octyl-β-glucoside and Pluronic F-127 to maximize the depth and yield of proteome extraction while maintaining native protein activity. This binary poloxamer extraction system allowed native proteome extraction, comparable in coverage to proteomes extracted using denaturing SDS or guanidine containing buffers, including efficient extraction of all major cellular organelles. This high-efficiency cellular extraction system should prove useful for a variety of cell biochemical studies, including structural and functional proteomics

A High-Efficiency Cellular Extraction System for Biological Proteomics

Recent developments in quantitative high-resolution mass spectrometry have led to significant improvements in the sensitivity and specificity of the biochemical analyses of cellular reactions, protein–protein interactions, and small-molecule-drug discovery. These approaches depend on cellular proteome extraction that preserves native protein activities. Here, we systematically analyzed mechanical methods of cell lysis and physical protein extraction to identify those that maximize the extraction of cellular proteins while minimizing their denaturation. Cells were mechanically disrupted using Potter–Elvehjem homogenization, probe- or adaptive-focused acoustic sonication, and were in the presence of various detergents, including polyoxyethylene ethers and esters, glycosides, and zwitterions. Using fluorescence spectroscopy, biochemical assays, and mass spectrometry proteomics, we identified the combination of adaptive focused acoustic (AFA) sonication in the presence of a binary poloxamer-based mixture of octyl-β-glucoside and Pluronic F-127 to maximize the depth and yield of the proteome extraction while maintaining native protein activity. This binary poloxamer extraction system allowed for native proteome extraction comparable in coverage to the proteomes extracted using denaturing SDS or guanidine-containing buffers, including the efficient extraction of all major cellular organelles. This high-efficiency cellular extraction system should prove useful for a variety of cell biochemical studies, including structural and functional proteomics

Targeting oncogenic interleukin-7 receptor signalling with N-acetylcysteine in T cell acute lymphoblastic leukaemia.

Activating mutations of the interleukin-7 receptor (IL7R) occur in approximately 10% of patients with T cell acute lymphoblastic leukaemia (T-ALL). Most mutations generate a cysteine at the transmembrane domain leading to receptor homodimerization through disulfide bond formation and ligand-independent activation of STAT5. We hypothesized that the reducing agent N-acetylcysteine (NAC), a well-tolerated drug used widely in clinical practice to treat acetaminophen overdose, would reduce disulfide bond formation, and inhibit mutant IL7R-mediated oncogenic signalling. We found that treatment with NAC disrupted IL7R homodimerization in IL7R-mutant DND-41 cells as assessed by non-reducing Western blot, as well as in a luciferase complementation assay. NAC led to STAT5 dephosphorylation and cell apoptosis at clinically achievable concentrations in DND-41 cells, and Ba/F3 cells transformed by an IL7R-mutant construct containing a cysteine insertion. The apoptotic effects of NAC could be rescued in part by a constitutively active allele of STAT5. Despite using doses lower than those tolerated in humans, NAC treatment significantly inhibited the progression of human DND-41 cells engrafted in immunodeficient mice. Thus, targeting leukaemogenic IL7R homodimerization with NAC offers a potentially effective and feasible therapeutic strategy that warrants testing in patients with T-ALL

Phenothiazines induce PP2A-mediated apoptosis in T cell acute lymphoblastic leukemia

T cell acute lymphoblastic leukemia (T-ALL) is an aggressive cancer that is frequently associated with activating mutations in NOTCH1 and dysregulation of MYC. Here, we performed 2 complementary screens to identify FDA-approved drugs and drug-like small molecules with activity against T-ALL. We developed a zebrafish system to screen small molecules for toxic activity toward MYC-overexpressing thymocytes and used a human T-ALL cell line to screen for small molecules that synergize with Notch inhibitors. We identified the antipsychotic drug perphenazine in both screens due to its ability to induce apoptosis in fish, mouse, and human T-ALL cells. Using ligand-affinity chromatography coupled with mass spectrometry, we identified protein phosphatase 2A (PP2A) as a perphenazine target. T-ALL cell lines treated with perphenazine exhibited rapid dephosphorylation of multiple PP2A substrates and subsequent apoptosis. Moreover, shRNA knockdown of specific PP2A subunits attenuated perphenazine activity, indicating that PP2A mediates the drug's antileukemic activity. Finally, human T-ALLs treated with perphenazine exhibited suppressed cell growth and dephosphorylation of PP2A targets in vitro and in vivo. Our findings provide a mechanistic explanation for the recurring identification of phenothiazines as a class of drugs with anticancer effects. Furthermore, these data suggest that pharmacologic PP2A activation in T-ALL and other cancers driven by hyperphosphorylated PP2A substrates has therapeutic potential

Data S1. Human PGBD5 DNA transposase promotes site-specific oncogenic mutations in rhabdoid tumors

Supplementary data S1 for Henssen et al. " Human PGBD5 DNA transposase promotes site-specific oncogenic mutations in rhabdoid tumors

MEF2C Phosphorylation Is Required for Chemotherapy Resistance in Acute Myeloid Leukemia

Abstract In acute myeloid leukemia (AML), chemotherapy resistance remains prevalent and poorly understood. Using functional proteomics of patient AML specimens, we identified MEF2C S222 phosphorylation as a specific marker of primary chemoresistance. We found that Mef2cS222A/S222A knock-in mutant mice engineered to block MEF2C phosphorylation exhibited normal hematopoiesis, but were resistant to leukemogenesis induced by MLL–AF9. MEF2C phosphorylation was required for leukemia stem cell maintenance and induced by MARK kinases in cells. Treatment with the selective MARK/SIK inhibitor MRT199665 caused apoptosis and conferred chemosensitivity in MEF2C-activated human AML cell lines and primary patient specimens, but not those lacking MEF2C phosphorylation. These findings identify kinase-dependent dysregulation of transcription factor control as a determinant of therapy response in AML, with immediate potential for improved diagnosis and therapy for this disease. Significance: Functional proteomics identifies phosphorylation of MEF2C in the majority of primary chemotherapy-resistant AML. Kinase-dependent dysregulation of this transcription factor confers susceptibility to MARK/SIK kinase inhibition in preclinical models, substantiating its clinical investigation for improved diagnosis and therapy of AML. Cancer Discov; 8(4); 478–97. ©2018 AACR. This article is highlighted in the In This Issue feature, p. 371</jats:p