• 제목/요약/키워드: C-myc

검색결과 201건 처리시간 0.036초

Costunolide Induces Differentiation of Human Leukemia HL-60 Cells

  • Choi, Jung-Hye;Seo, Bo-Rim;Seo, Seong-Hoon;Lee, Kyung-Tae;Park, Jae-Hoon;Park, Hee-Juhn;Choi, Jong-Won;Yoshie-Itoh;Miyamoto, Ken-Ichi
    • Archives of Pharmacal Research
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    • 제25권4호
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    • pp.480-484
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    • 2002
  • Costunolide has been reported to be a cytotoxic and chemopreventive agent. This work investigated the mechanism of the anti proliferative effect of costunolide and determined that it induced differentiation of the human leukemia cell line HL-60. Costunolide exhibited a potent antiproliferative activity against HL-60 cells. It was also found to be a potent inducer of differentiation in human leukemia derived HL-60 cells through the examination of differentiation markers, as assessed by the reduction of nitroblue tetrazolium, the increase in esterase activities and phagocytic activity, morphology change and the expression of CD14 and CD66b surface antigens. These results, accompanied by a decline in the expression of c-myc protein, suggest that costunolide induces differentiation of human leukemia cells to granulocytes and monocytes/macrophages lineage.

Intraoral HIV-associated Burkitt's lymphoma: a rare case report with special emphasis on differential diagnosis

  • Kamat, Mamata;Datar, Uma;Kanitkar, Sampada;Byakodi, Sanjay
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제45권4호
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    • pp.225-229
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    • 2019
  • Individuals with human immunodeficiency virus (HIV) infection present with unique intraoral manifestations of various neoplasms. Intraoral HIV-associated Burkitt's lymphoma is a rare presentation, especially in patients of Indian origin and may present as an initial sign of HIV. The objective of this paper is to report a rare case of Burkitt's lymphoma in an HIV-positive Indian patient along with a special emphasis on differential diagnosis. A 30-year-old Indian female presented with a solitary, well-defined, exophytic mass extending anteroposteriorly and buccolingually from the 35th to 38th regions with no evidence of intraosseous extension. An incisional biopsy was performed, and histopathology showed sheets of neoplastic lymphoid cells with numerous tingible body macrophages with clear cytoplasm, presenting a starry sky appearance, suggesting a diagnosis of BL. The tumor cells were positive for CD10, CD20, c-myc, and Epstein-Barr virus, with a nearly 100% Ki-67 proliferative index. The patient tested positive for HIV. This report indicates the importance of immunohistochemical analysis to differentiate Burkitt's lymphoma from other similar lesions like diffuse large B-cell lymphoma. Thorough knowledge of the clinical presentation, etiopathogenesis, histopathology, and immunoprofile of intraoral HIV-associated Burkitt's lymphoma is essential among clinicians and pathologists.

Melatonin inhibits glycolysis in hepatocellular carcinoma cells by downregulating mitochondrial respiration and mTORC1 activity

  • Lee, Seunghyeong;Byun, Jun-Kyu;Kim, Na-Young;Jin, Jonghwa;Woo, Hyein;Choi, Yeon-Kyung;Park, Keun-Gyu
    • BMB Reports
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    • 제55권9호
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    • pp.459-464
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    • 2022
  • Various mechanisms have been suggested to explain the chemopreventive and tumor-inhibitory effects of melatonin. Despite the growing evidence supporting melatonin-induced mitochondrial dysfunction, it remains largely unknown how this phenomenon modulates metabolic reprogramming in cancer cells. The aim of our study was to identify the mechanism underlying the anti-proliferative and apoptotic effects of melatonin, which is known to inhibit glycolysis. We analyzed the time-dependent effects of melatonin on mitochondrial respiration and glycolysis in liver cancer cells. The results showed that from a cell bioenergetic point of view, melatonin caused an acute reduction in mitochondrial respiration, however, increased reactive oxygen species production, thereby inhibiting mTORC1 activity from an early stage post-treatment without affecting glycolysis. Nevertheless, administration of melatonin for a longer time reduced expression of c-Myc protein, thereby suppressing glycolysis via downregulation of HK2 and LDHA. The data presented herein suggest that melatonin suppresses mitochondrial respiration and glycolysis simultaneously in HCC cells, leading to anti-cancer effects. Thus, melatonin can be used as an adjuvant agent for therapy of liver cancer.

CKD-581 Downregulates Wnt/β-Catenin Pathway by DACT3 Induction in Hematologic Malignancy

  • Kim, Soo Jin;Kim, Suntae;Choi, Yong June;Kim, U Ji;Kang, Keon Wook
    • Biomolecules & Therapeutics
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    • 제30권5호
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    • pp.435-446
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    • 2022
  • The present study evaluated the anti-cancer activity of histone deacetylase (HDAC)-inhibiting CKD-581 in multiple myeloma (MM) and its pharmacological mechanisms. CKD-581 potently inhibited a broad spectrum of HDAC isozymes. It concentration-dependently inhibited proliferation of hematologic cancer cells including MM (MM.1S and RPMI8226) and T cell lymphoma (HH and MJ). It increased the expression of the dishevelled binding antagonist of β-catenin 3 (DACT3) in T cell lymphoma and MM cells, and decreased the expression of c-Myc and β-catenin in MM cells. Additionally, it enhanced phosphorylated p53, p21, cleaved caspase-3 and the subG1 population, and reversely, downregulated cyclin D1, CDK4 and the anti-apoptotic BCL-2 family. Finally, administration of CKD-581 exerted a significant anti-cancer activity in MM.1S-implanted xenografts. Overall, CKD-581 shows anticancer activity via inhibition of the Wnt/β-catenin signaling pathway in hematologic malignancies. This finding is evidence of the therapeutic potential and rationale of CKD-581 for treatment of MM.

Backbone Cyclization of Flavin Mononucleotide-Based Fluorescent Protein Increases Fluorescence and Stability

  • Tingting Lin;Yuanyuan Ge;Qing Gao;Di Zhang;Xiaofeng Chen;Yafang Hu;Jun Fan
    • Journal of Microbiology and Biotechnology
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    • 제33권12호
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    • pp.1681-1691
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    • 2023
  • Flavin mononucleotide-binding proteins or domains emit cyan-green fluorescence under aerobic and anaerobic conditions, but relatively low fluorescence and less thermostability limit their application as reporters. In this work, we incorporated the codon-optimized fluorescent protein from Chlamydomonas reinhardtii with two different linkers independently into the redox-responsive split intein construct, overexpressed the precursors in hyperoxic Escherichia coli SHuffle T7 strain, and cyclized the target proteins in vitro in the presence of the reducing agent. Compared with the purified linear protein, the cyclic protein with the short linker displayed enhanced fluorescence. In contrast, cyclized protein with incorporation of the long linker including the myc-tag and human rhinovirus 3C protease cleavable sequence emitted slightly increased fluorescence compared with the protein linearized with the protease cleavage. The cyclic protein with the short linker also exhibited increased thermal stability and exopeptidase resistance. Moreover, induction of the target proteins in an oxygen-deficient culture rendered fluorescent E. coli BL21 (DE3) cells brighter than those overexpressing the linear construct. Thus, the cyclic reporter can hopefully be used in certain thermophilic anaerobes.

D-galactose induces astrocytic aging and contributes to astrocytoma progression and chemoresistance via cellular senescence

  • Jingang Hou;Yeejin Yun;Jianjie Xue;Mengqi Sun;Sunchang Kim
    • Molecular Medicine Reports
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    • 제20권5호
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    • pp.4111-4118
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    • 2019
  • The administration of D-galactose triggers brain aging by poorly understood mechanisms. It is generally recognized that D-galactose induces oxidative stress or affects protein modifications via receptors for advanced glycated end products in a variety of species. In the present study, we aimed to investigate the involvement of astrocytes in D-galactose-induced brain aging in vitro. We found that D-galactose treatment significantly suppressed cell viability and induced cellular senescence. In addition, as of the accumulation of senescent cells, we proposed that the senescence-associated secretory phenotype (SASP) can stimulate age-related pathologies and chemoresistance in brain. Consistently, senescent astrocytic CRT cells induced by D-galactose exhibited increases in the levels of IL-6 and IL-8 via NF-κB activation, which are major SASP components and inflammatory cytokines. Conditioned medium prepared from senescent astrocytic CRT cells significantly promoted the viability of brain tumor cells (U373-MG and N2a). Importantly, conditioned medium greatly suppressed the cytotoxicity of U373-MG cells induced by temozolomide, and reduced the protein expression levels of neuron marker neuron-specific class III β-tubulin, but markedly increased the levels of c-Myc in N2a cells. Thus, our findings demonstrated that D-galactose treatment might mimic brain aging, and that D-galactose could contribute to brain inflammation and tumor progression through inducing the accumulation of senescent-secretory astrocytes.

Interactions between secreted GRA proteins and host cell proteins across the parasitophorous vacuolar membrane in the parasitism of Toxoplasma gondii

  • Ahn, Hye-Jin;Kim, Sehra;Kim, Hee-Eun;Nam, Ho-Woo
    • Parasites, Hosts and Diseases
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    • 제44권4호
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    • pp.303-312
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    • 2006
  • Interactions between GRA proteins of dense granules in Toxoplasma gondii and host cell proteins were analyzed by yeast two-hybrid technique. The cMyc-GRA fusion proteins expressed from pGBKT7 plasmid in Y187 yeast were bound to host cell proteins from pGADT7-Rec-HeLa cDNA library transformed to AH109 yeast by mating method. By the selection procedures, a total of 939 colonies of the SD/-AHLT culture, 348 colonies of the $X-\alpha-gal$ positive and PCR, 157 colonies of the $X-\beta-gal$ assay were chosen for sequencing the cDNA and finally 90 colonies containing ORF were selected to analyze the interactions. GRA proteins interacted with a variety of host cell proteins such as enzymes, structural and functional proteins of organellar proteins of broad spectrum. Several specific bindings of each GRA protein to host proteins were discussed presumptively the role of GRA proteins after secreting into the parasitophorous vacuoles (PV) and the PV membrane in the parasitism of this parasite.

Incapability of Utilizing Galactose by pgs1 Mutation Occurred on the Galactose Incorporation Step in Saccharomyces cerevisiae

  • Rho, Min-Suk;Su, Xuefeng;Lee, Yoon-Shik;Kim, Woo-Ho;Dowhan, William
    • Journal of Microbiology and Biotechnology
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    • 제16권1호
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    • pp.84-91
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    • 2006
  • A Saccharomyces cerevisiae pgs1 nulI mutant, which is deficient with phosphatidyl glycerol (PG) and cardiolipin (CL) biosynthesis, grows well on most fermentable carbon sources, but fails to grow on non-fermentable carbon sources such as glycerol, ethanol, and lactate. This mutant also cannot grow on galactose medium as the sole carbon source. We found that the incorporation of $[^{14}C]-galactose$, which is the first step of the galactose metabolic pathway (Leloir pathway), into the pgs 1 null mutant cell was extremely repressed. Exogenously expressed PGS1 (YCpPGS1) under indigenous promoter could completely restore the pgs1 growth defect on non-fermentable carbon sources, and dramatically recovered $[^{14}C]-galactose$ incorporation into the pgs1 mutant cell. However, PGS1 expression under the GALl promoter $(YEpP_{GAL1}-PGS1myc)$ could not complement pgs1 mutation, and the GAL2-lacZ fusion gene $(YEpP_{GAL2}-lacZ)$ also did not exhibit its $\beta-galactosidase$ activity in the pgs1 mutant. In wild-type yeast, antimycin $A(1\;{\mu}g/ml)$, which inhibits mitochondrial complex III, severely repressed not only the expression of the GAL2-lacZ fusion gene, but also uptake of $[^{14}C]-galactose$. However, exogenously expressed PGS1 partially relieved these inhibitory effects of antimycin A in both the pgs1 mutant and wild-type yeast, although it could not basically restore the growth defect on galactose by antimycin A. These results suggest that the PGSI gene product has an important role in utilization of galactose by Gal genes, and that intact mitochondrial function with PGS1 should be required for galactose incorporation into the Leloir pathway. The PGS1 gene might provide a clue to resolve the historic issue about the incapability of galactose with deteriorated mitochondrial function.

Identification of Novel Alternatively Spliced Transcripts of RBMS3 in Skeletal Muscle with Correlations to Insulin Action in vivo

  • Lee, Yong-Ho;Tokraks, Stephen;Nair, Saraswathy;Bogardus, Clifton;Permana, Paska A.
    • 대한의생명과학회지
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    • 제15권4호
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    • pp.301-307
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    • 2009
  • Whole-body insulin resistance results largely from impaired insulin-stimulated glucose disposal in skeletal muscle. Our previous studies using differential display and quantitative real-time RT-PCR have shown that a novel cDNA band (DD23) had a higher level of expression in insulin resistant skeletal muscle and it was correlated with whole-body insulin action, independent of age, sex, and percent body fat. In this study, we cloned and characterized DD23. The DD23 sequence is part of the 3'UTR region of the RNA binding motif, single stranded interacting protein (RBMS3). We have cloned the full length cDNA for RBMS3 and identified two splice variants. These variants named DD23-L and DD23-S have 15 and 14 exons respectively and differ from RBMS3 in the 3'UTR significantly. Northern blot analyses showed that an ~8.8 kb mRNA transcript of DD23 was predominantly expressed in skeletal muscle and to a lesser extent in placenta, but not in heart, brain, lung, liver, or kidney, unlike RBMS3. Elevated expression levels of these novel alternatively spliced variants of RBMS3 in skeletal muscle may play a role in whole body insulin resistance.

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Anti-Cancer Effects and Apoptosis by Korean Medicinal Herbs

  • Ko Seong Gyu;Jun Chan Yong;Park Chong Hyeong;Bae Hyun Su
    • 동의생리병리학회지
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    • 제17권3호
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    • pp.819-825
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    • 2003
  • pharbitis nil and Taraxacum mongolicum are representative herbs that have been used for cancer treatment in Korean traditional medicine. To understand the molecular basis of the antitumor function, we analyzed the effect of these herbs on proliferation and apoptosis of tumor cells using a gastric cancer cell line AGS. Cell counting assay showed that pharbitis nil strongly inhibit cell proliferation Of AGS whereas Taraxacum mongolicum exhibit no detectable effect on cellular growth. [³H]thymidine uptake analysis also demonstrated that DNA replication of AGS is suppressed in a dose-dependent manner by treatment with pharbitis nil. Additionally, tryphan blue exclusion assay showed that Pharbitis nil induce apoptotic cell death of AGS in a dose-dependent. To explore whether anti antiproliferative and/or proapototic property of Pharbitis nil is associated with their effect on gene expression, we performed RT-PCR analysis of cell cycle- and apoptosis-related genes. Interestingly, mRNA expression levels of c-Jun, c-Fos, c-Myc, and Cyclin D1 were markedly reduced by Pharbitis nil. Taraxacum mongolicum also showed inhibitory action on expression of these growth-promoting protooncogene but there effects are less significant, as compared to Pharbitis nil. Furthermore, it was also found that Pharbitis nil activates expression of the p53 tumor suppressor and its downstream effector p21Waf1, which induce G1 cell cycle arrest and apoptosis. Collectively, our data demonstrate that Pharbitis nil induce growth inhibition and apoptosis of human gastric cancer cells and these effects are accompanied with down-and up-regulation of growth-regulating protooncogenes and tumor suppressor genes, respectively. This observation thus suggests that the anticancer effect of Pharbitis nil might be associated with its regulatory capability of tumor-related gene expression.