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1.
J Korean Soc Radiol ; 84(6): 1367-1372, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38107679

ABSTRACT

Primary angiitis of the central nervous system (PACNS) is a rare vasculitis in the central nervous system. Herein, we report a case of diagnosis and treatment of necrotic pattern PACNS, which was difficult to differentiate from a brain abscess. A 19-year-old male presented with blurred vision and a headache. Brain MRI revealed irregular rim-enhancing necrotic masses with central diffusion-high signal intensity in the corpus callosum and peripheral diffusion-high signal intensity in the left parietotemporal periventricular area. Susceptibility-weighted imaging revealed multiple punctate hemorrhages in the lesions. The patient was diagnosed with unusual abscess or tumefactive PACNS. Therefore, we initially treated the patient with antibiotics to rule out brain abscess. However, the brain lesions did not improve on follow-up MRI after the antibiotic treatment. Surgical biopsy was performed, and the histopathological diagnosis was PACNS with a necrotic pattern. The necrotic lesions became smaller on follow-up MRI after high-dose corticosteroid treatment.

2.
J Korean Soc Radiol ; 84(5): 1140-1145, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37869121

ABSTRACT

Cerebral amyloid angiopathy-related inflammation (CAA-RI) is an encephalopathy caused by inflammation of ß-amyloid peptide deposition in cerebrovascular vessels. It is a rare disease that mainly occurs in the elderly and is characterized by rapidly progressive dementia, headache, seizures, and focal neurologic deficits. CAA-RI can demonstrate characteristic brain MRI findings and can be reversed by steroids or other immunosuppressive therapies. Here, we report a case of CAA-RI, which was initially misdiagnosed as a subacute infarction but was diagnosed while reviewing follow-up brain MRI images, and spontaneous remission was achieved.

3.
J Korean Soc Radiol ; 84(5): 1080-1090, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37869130

ABSTRACT

Purpose: This study aimed to compare the volume and normative percentiles of brain volumetry in the Korean population using quantitative brain volumetric MRI analysis tools NeuroQuant® (NQ) and DeepBrain® (DB), and to evaluate whether the differences in the normative percentiles of brain volumetry between the two tools is related to cranial shape. Materials and Methods: In this retrospective study, we analyzed the brain volume reports obtained from NQ and DB in 163 participants without gross structural brain abnormalities. We measured three-dimensional diameters to evaluate the cranial shape on T1-weighted images. Statistical analyses were performed using intra-class correlation coefficients and linear correlations. Results: The mean normative percentiles of the thalamus (90.8 vs. 63.3 percentile), putamen (90.0 vs. 60.0 percentile), and parietal lobe (80.1 vs. 74.1 percentile) were larger in the NQ group than in the DB group, whereas that of the occipital lobe (18.4 vs. 68.5 percentile) was smaller in the NQ group than in the DB group. We found a significant correlation between the mean normative percentiles obtained from the NQ and cranial shape: the mean normative percentile of the occipital lobe increased with the anteroposterior diameter and decreased with the craniocaudal diameter. Conclusion: The mean normative percentiles obtained from NQ and DB differed significantly for many brain regions, and these differences may be related to cranial shape.

4.
BMC Med Imaging ; 22(1): 219, 2022 12 17.
Article in English | MEDLINE | ID: mdl-36536325

ABSTRACT

BACKGROUND: Knowing the lowest acceptable radiation dose of multiphase hepatic CT may allow us to reduce the radiation dose for detecting HCC. PURPOSE: To prospectively assess the image quality and diagnostic performance of low-dose and ultra-low-dose multiphase hepatic computed tomography using a dual-source CT scanner. METHODS: Three reconstructed different dose scan images (standard-dose, low-dose, and ultra-low-dose) of hepatic multiphase CT were obtained from 67 patients with a dual-source CT scanner. The image quality and the diagnostic performance of the three radiation dose CT scans of the hepatic focal lesion (≥ 0.5 cm) were analyzed by two independent readers using the Liver Imaging Reporting and Data System. RESULTS: Qualitative image quality and signal-to-noise ratio were significantly different among the radiation doses (p < 0.001). In total, 154 lesions comprising 32 hepatocellular carcinomas (HCC) and 122 non-HCC were included. The sensitivities of SDCT, LDCT, and ULDCT were 90.6%(29/32), 81.3%(26/32), and 56.2%(18/32), respectively. The accuracies of SDCT, LDCT, and ULDCT were 98.1%(151/154), 96.1%(148/154), and 89.6%(138/154), respectively. On per-lesion analysis, SDCT and LDCT did not show significantly different sensitivity and accuracy in diagnosing HCC (p = 0.250 and 0.250). CONCLUSIONS: The diagnostic performance of dynamic hepatic LDCT with 33% reduced radiation dose in comparison to SDCT would be acceptable even though its image quality was qualitatively and quantitatively inferior. However, few HCCs could be overlooked. Therefore, with caution, radiation dose reduction by one-third could be implemented for follow-up CT scans for patients suspected of having HCC with caution and further studies are needed in the future.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/diagnostic imaging , Radiation Dosage , Liver Neoplasms/diagnostic imaging , Tomography, X-Ray Computed/methods , Radiographic Image Interpretation, Computer-Assisted/methods
5.
Acta Radiol ; 63(11): 1453-1462, 2022 Nov.
Article in English | MEDLINE | ID: mdl-34839679

ABSTRACT

BACKGROUND: Knowing the advantages and disadvantages of each magnetic resonance (MR) technique, would allow us to choose a sequence better suited in patients with a high risk of breath-holding failure. PURPOSE: To compare the image quality of free-breathing contrast-enhanced multiphase MR imaging (MRI) using incoherent Cartesian k-space sampling combined with a motion-resolved compressed sensing reconstruction (XD-VIBE) and Golden-Angle Radial Sparse Parallel MRI (GRASP). MATERIAL AND METHODS: A total of 67 patients were included. Overall image quality, motion artifacts, and liver edge sharpness on arterial and portal-venous phase were evaluated by two radiologists. We evaluated the signal intensity ratio between liver in the late arterial phase to aorta at peak enhancement and the detection rate of hypervascular lesions. RESULTS: Overall image quality, artifact, and liver edge sharpness scores of XD-VIBE and GRASP were not significantly different (P = 0.070-0.397). Four (reviewer 1, 12.1%) and seven patients (reviewer 2, 21.2%) received non-diagnostic quality in the XD-VIBE group whereas one patient (reviewer 2, 2.9%) received non-diagnostic quality in the GRASP group. The ratio between the aorta and liver signal for GRASP was significantly higher than that of XD-VIBE (0.32 ± 0.10 vs. 0.47 ± 0.13; P < 0.001). The hypervascular lesion detection rate of XD-VIBE (86.7%) was higher than that of GRASP (57.1%) in the arterial phase without a statistically significant difference (P = 0.081). CONCLUSION: Overall image quality of XD-VIBE and GRASP were not significantly different. More XD-VIBE examinations were rated non-diagnostic. On the other hand, the relative liver parenchymal enhancement to the aorta in the late arterial phase of GRASP was higher than that of XD-VIBE, which potentially leads to lower detectability of hypervascular lesions on arterial phase images.


Subject(s)
Contrast Media , Magnetic Resonance Imaging , Artifacts , Breath Holding , Humans , Image Enhancement/methods , Imaging, Three-Dimensional/methods , Liver/diagnostic imaging , Liver/pathology , Magnetic Resonance Imaging/methods , Respiration
6.
Ann Lab Med ; 41(5): 489-492, 2021 Sep 01.
Article in English | MEDLINE | ID: mdl-33824238

ABSTRACT

Botulism is a neuroparalytic disease caused by a neurotoxin produced by Clostridium botulinum. This study aimed to genetically characterize C. botulinum strain isolated from the first case of infant botulism in Korea reported on June 17, 2019. We isolated C. botulinum strain CB-27 from a stool sample of the patient and analyzed the toxin types and toxin gene cluster compositions of the strain using a mouse bioassay, real-time PCR, and genome sequencing. Toxin gene cluster analysis showed that strain CB-27 possesses a C. botulinum neurotoxin type A harboring an unexpressed B gene. Although the nucleotide and amino acid sequences of toxin genes as well as the toxin gene cluster arrangements in strain CB-27 were identical to those of the known strain CDC_69094, the total nucleotide sequences of the toxin gene clusters of CB-27 differed from those of CDC_69094 by 0.47%, indicating genetic diversity of toxin gene clusters of CB-27 among other previously reported C. botulinum strains. To our knowledge, this is the first description of a C. botulinum strain with two separate toxin gene clusters in Korea.


Subject(s)
Botulinum Toxins , Botulism , Clostridium botulinum , Botulinum Toxins/genetics , Botulism/diagnosis , Clostridium botulinum/genetics , Humans , Infant , Phylogeny , Republic of Korea
7.
Heart Lung Circ ; 30(6): 817-836, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33541820

ABSTRACT

AIMS: To identify the biomedical, socioeconomic and demographic predictors of heart failure (HF) related readmissions in adult patients with HF. METHODS: This systematic review was conducted in March 2020 using the databases EMBASE, CINAHL and Medline to identify publications between 2015-2020. The resulting articles were systematically reviewed according to the PRISMA guidelines. RESULTS: Eighteen (18) studies were included in this review. Unemployment (HR=1.09; 95%CI=1.05-1.14; p=0.03) was the only socioeconomic factor predictive of HF-readmissions. Socio-Economic Indexes for Areas (SEIFA) scores did not predict HF readmissions in adults with HF (p>0.05). All patients included in the studies had pre-existing HF. Based on the included studies, Indigenous status was identified as a risk factor for HF readmissions in 1 study (p<0.05), and age or sex did not affect HF readmission patterns (p>0.05). New York Heart Association (NYHA) class, brain natriuretic peptide (BNP) levels, and heart rate were also predictive of HF readmission (p<0.05). Left ventricular ejection fraction and blood pressure, however, were non-significant risk factors of HF readmissions (p>0.05). CONCLUSIONS: This review identified unemployment, Indigenous status, NYHA class, heart rate, and BNP levels to predict HF related readmissions in adult patients with HF. Adding demographic and socioeconomic variables to readmission risk models has the potential to more accurately target patients at risk of readmissions.


Subject(s)
Heart Failure , Patient Readmission , Adult , Demography , Heart Failure/diagnosis , Heart Failure/epidemiology , Heart Failure/therapy , Humans , Socioeconomic Factors , Stroke Volume , Ventricular Function, Left
8.
Anticancer Res ; 38(1): 271-277, 2018 01.
Article in English | MEDLINE | ID: mdl-29277783

ABSTRACT

The ultraviolent irradiation resistance-associated gene (UVRAG), a component of the Beclin 1/autophagy-related 6 complex, regulates the autophagy initiation step and functions in the DNA-damage response. UVRAG is frequently mutated in various cancer types, and mutations of UVRAG increase sensitivity to chemotherapy by impairing DNA-damage repair. In this study, we addressed the epigenetic regulation of UVRAG in colorectal cancer cells. UVRAG expression was increased in cells treated with histone deacetylase (HDAC) inhibitors, such as valproic acid and suberoylanilide hydroxamic acid. Down-regulation of HDAC1 enhanced UVRAG expression in colorectal cancer cells. In addition, both chemical and genetic inhibition of HDAC1 reduced the activation of caspase-3 and cytotoxicity in 5-fluorouracil (5FU)-treated cancer cells. In contrast, UVRAG overexpression inhibited caspase activation and cell death in 5FU-treated cells. Taken together, our findings suggest that up-regulation of UVRAG by HDAC1 inhibition potentiates DNA-damage-mediated cell death in colorectal cancer cells.


Subject(s)
Antimetabolites, Antineoplastic/pharmacology , Colorectal Neoplasms/metabolism , Fluorouracil/pharmacology , Histone Deacetylase 1/antagonists & inhibitors , Tumor Suppressor Proteins/metabolism , Cell Death/drug effects , Colorectal Neoplasms/drug therapy , DNA Damage , Epigenesis, Genetic , HCT116 Cells , Histone Deacetylase 1/metabolism , Histone Deacetylase Inhibitors/pharmacology , Humans , Up-Regulation
9.
Cell Oncol (Dordr) ; 40(3): 235-246, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28401485

ABSTRACT

PURPOSE: Approximately 20% of all salivary gland cancer patients who are treated with current treatment modalities will ultimately develop metastases. Its most common form, mucoepidermoid carcinoma (MEC) is a highly aggressive tumor with an overall 5-year survival rate of ~30%. Until now, several chemotherapeutic drugs have been tested for the treatment of salivary gland tumors, but the results have been disappointing and the drugs often cause unwanted side effects. Therefore, several recent studies have focused on the potential of alternative and/or complementary therapeutic options, including the use of silymarin. METHODS: The effects of silymarin and its active component silibinin on salivary gland cancer-derived MC3 and HN22 cells and their underlying molecular mechanisms were examined using trypan blue exclusion, 4'-6-diamidino-2-phenylindole (DAPI) staining, Live/Dead, Annexin V/PI staining, mitochondrial membrane potential (ΔΨm) measurement, quantitative RT-PCR, soft agar colony formation and Western blotting analyses. RESULTS: We found that silymarin and silibinin dramatically increased the expression of the pro-apoptotic protein Bim in a concentration- and time-dependent manner and, concomitantly, induced apoptosis in MC3 and HN22 cells. We also found that ERK1/2 signaling inhibition successfully sensitized these cells to the apoptotic effects of silymarin and silibinin, which indicates that the ERK1/2 signaling pathway may act as an upstream regulator that modulates the silymarin/silibinin-induced Bim signaling pathway. CONCLUSIONS: Taken together, we conclude that ERK1/2 signaling pathway inhibition by silymarin and silibinin increases the expression of the pro-apoptotic Bcl-2 family member Bim which, subsequently, induces mitochondria-mediated apoptosis in salivary gland cancer-derived cells.


Subject(s)
Bcl-2-Like Protein 11/drug effects , MAP Kinase Signaling System/drug effects , Salivary Gland Neoplasms/pathology , Silymarin/pharmacology , Antioxidants/pharmacology , Apoptosis/drug effects , Cell Cycle/drug effects , Cell Line, Tumor , Humans , Silybin
10.
Cancer Lett ; 385: 21-27, 2017 01 28.
Article in English | MEDLINE | ID: mdl-27836735

ABSTRACT

Autophagy plays complex roles in tumor initiation and development, and the expression of autophagy-related genes (ATGs) is differentially regulated in various cancer cells, depending on their environment. In this study, we analyzed the expressional relationship between polypyrimidine tract-binding protein 1 (PTBP1) and ATG10 in metastatic colorectal cancer. PTBP1 is associated with tumor metastasis in primary colorectal tumors and colorectal cancer liver metastasis (CLM) tissues. In addition, PTPB1 directly interacts with mRNA of ATG10, and regulates ATG10 expression level in colorectal cancer cells. Ectopic expression of PTBP1 decreased ATG10 expression, whereas down-regulation of PTBP1 increased ATG10 level. In contrast to PTBP1, expression of ATG10 was decreased in CLM tissues. Knock down of ATG10 promoted cell migration and invasion of colorectal cancer cells. Moreover, depletion of ATG10 modulated epithelial-mesenchymal transition-associated proteins in colorectal cancer cells: N-cadherin, TCF-8/ZEB1, and CD44 were up-regulated, whereas E-cadherin was down-regulated. Taken together, our findings suggest that expression of ATG10 negatively regulated by PTBP1 is associated with metastasis of colorectal cancer cells.


Subject(s)
Autophagy-Related Proteins/metabolism , Cell Movement , Colorectal Neoplasms/metabolism , Heterogeneous-Nuclear Ribonucleoproteins/metabolism , Polypyrimidine Tract-Binding Protein/metabolism , Vesicular Transport Proteins/metabolism , Antigens, CD/metabolism , Autophagy-Related Proteins/genetics , Cadherins/metabolism , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Down-Regulation , Epithelial-Mesenchymal Transition , Gene Expression Regulation, Neoplastic , HCT116 Cells , Heterogeneous-Nuclear Ribonucleoproteins/genetics , Humans , Hyaluronan Receptors/metabolism , Neoplasm Invasiveness , Neoplasm Metastasis , Polypyrimidine Tract-Binding Protein/genetics , RNA Interference , RNA, Messenger/genetics , RNA, Messenger/metabolism , Signal Transduction , Transfection , Vesicular Transport Proteins/genetics , Zinc Finger E-box-Binding Homeobox 1/metabolism
11.
PLoS One ; 9(11): e112130, 2014.
Article in English | MEDLINE | ID: mdl-25390895

ABSTRACT

To date, several regulatory proteins involved in mitochondrial dynamics have been identified. However, the precise mechanism coordinating these complex processes remains unclear. Mitochondrial chaperones regulate mitochondrial function and structure. Chaperonin 10 (Cpn10) interacts with heat shock protein 60 (HSP60) and functions as a co-chaperone. In this study, we found that down-regulation of Cpn10 highly promoted mitochondrial fragmentation in SK-N-MC and SH-SY5Y neuroblastoma cells. Both genetic and chemical inhibition of Drp1 suppressed the mitochondrial fragmentation induced by Cpn10 reduction. Reactive oxygen species (ROS) generation in 3-NP-treated cells was markedly enhanced by Cpn10 knock down. Depletion of Cpn10 synergistically increased cell death in response to 3-NP treatment. Furthermore, inhibition of Drp1 recovered Cpn10-mediated mitochondrial dysfunction in 3-NP-treated cells. Moreover, an ROS scavenger suppressed cell death mediated by Cpn10 knockdown in 3-NP-treated cells. Taken together, these results showed that down-regulation of Cpn10 increased mitochondrial fragmentation and potentiated 3-NP-mediated mitochondrial dysfunction in neuroblastoma cells.


Subject(s)
Chaperonin 10/metabolism , Mitochondria/pathology , Mitochondrial Dynamics , Neuroblastoma/physiopathology , Apoptosis/drug effects , Cell Line, Tumor , Chaperonin 10/antagonists & inhibitors , Chaperonin 10/genetics , Down-Regulation/drug effects , Dynamins , GTP Phosphohydrolases/antagonists & inhibitors , GTP Phosphohydrolases/genetics , GTP Phosphohydrolases/metabolism , Humans , Membrane Potential, Mitochondrial/drug effects , Microtubule-Associated Proteins/antagonists & inhibitors , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , Mitochondria/drug effects , Mitochondria/genetics , Mitochondria/metabolism , Mitochondrial Proteins/antagonists & inhibitors , Mitochondrial Proteins/genetics , Mitochondrial Proteins/metabolism , Neuroblastoma/metabolism , Nitro Compounds/pharmacology , Propionates/pharmacology , RNA Interference , RNA, Small Interfering/metabolism , Reactive Oxygen Species/metabolism
12.
Sci Rep ; 4: 7162, 2014 Nov 24.
Article in English | MEDLINE | ID: mdl-25418289

ABSTRACT

Cervical cancer is the third most common cancer and the third leading cause of death among women. However, the standard treatment for cervical cancer includes cisplatin, which can cause side effects such as hematological damage or renal toxicity. New innovations in cervical cancer treatment focus on developing more effective and better-tolerated therapies such as Sp1-targeting drugs. Previous studies suggested that mithramycin A (Mith) inhibits the growth of various cancers by decreasing Sp1 protein. However, how Sp1 protein is decreased by Mith is not clear. Few studies have investigated the regulation of Sp1 protein by proteasome-dependent degradation as a possible control mechanism for the regulation of Sp1 in cancer cells. Here, we show that Mith decreased Sp1 protein by inducing proteasome-dependent degradation, thereby suppressing cervical cancer growth through a DR5/caspase-8/Bid signaling pathway. We found that prolonged Mith treatment was well tolerated after systemic administration to mice carrying cervical cancer cells. Reduction of body weight was minimal, indicating that Mith was a good therapeutic candidate for treatment of cancers in which Sp1 is involved in promoting and developing disease.


Subject(s)
Cell Proliferation/drug effects , Plicamycin/analogs & derivatives , Signal Transduction/drug effects , Sp1 Transcription Factor/metabolism , Uterine Cervical Neoplasms/drug therapy , Animals , Antibiotics, Antineoplastic/pharmacology , Antibiotics, Antineoplastic/therapeutic use , Apoptosis/drug effects , BH3 Interacting Domain Death Agonist Protein/metabolism , Caspase 8/metabolism , Cell Line, Tumor , Female , Humans , Membrane Potential, Mitochondrial/drug effects , Mice , Mice, Nude , Mitochondria/drug effects , Mitochondria/metabolism , Peptide Hydrolases/metabolism , Plicamycin/pharmacology , Plicamycin/therapeutic use , RNA Interference , Receptors, TNF-Related Apoptosis-Inducing Ligand/metabolism , Sp1 Transcription Factor/antagonists & inhibitors , Sp1 Transcription Factor/genetics , Transplantation, Heterologous , Uterine Cervical Neoplasms/pathology
13.
Pigment Cell Melanoma Res ; 27(6): 1051-62, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25065405

ABSTRACT

Mitochondrial dynamics control mitochondrial functions as well as their morphology. However, the role of mitochondrial dynamics in melanogenesis is largely unknown. Here, we show that mitochondrial dynamics regulate melanogenesis by modulating the ROS-ERK signaling pathway. Genetic and chemical inhibition of Drp1, a mitochondrial fission protein, increased melanin production and mitochondrial elongation in melanocytes and melanoma cells. In contrast, down-regulation of OPA1, a mitochondria fusion regulator, suppressed melanogensis but induced massive mitochondrial fragmentation in hyperpigmented cells. Consistently, treatment with CCCP, a mitochondrial fission chemical inducer, also efficiently repressed melanogenesis. Furthermore, we found that ROS production and ERK phosphorylation were increased in cells with fragmented mitochondria. And inhibition of ROS or ERK suppressed the antimelanogenic effect of mitochondrial fission in α-MSH-treated cells. In addition, the activation of ROS-ERK pathway by mitochondrial fission induced phosphorylation of serine73 on MITF accelerating its proteasomal degradation. In conclusion, mitochondrial dynamics may regulate melanogenesis by modulating ROS-ERK signaling pathway.


Subject(s)
Extracellular Signal-Regulated MAP Kinases/metabolism , Melanins/biosynthesis , Microphthalmia-Associated Transcription Factor/metabolism , Mitochondrial Dynamics , Proteasome Endopeptidase Complex/metabolism , Proteolysis , Reactive Oxygen Species/metabolism , Animals , Carbonyl Cyanide m-Chlorophenyl Hydrazone/pharmacology , Cell Line, Tumor , Down-Regulation/drug effects , Dynamins/metabolism , Epidermal Cells , Humans , Melanocytes/drug effects , Melanocytes/enzymology , Melanoma, Experimental/metabolism , Melanoma, Experimental/pathology , Mice, Inbred C57BL , Mitochondrial Dynamics/drug effects , Mitogen-Activated Protein Kinase Kinases/antagonists & inhibitors , Mitogen-Activated Protein Kinase Kinases/metabolism , Proteolysis/drug effects , Quinazolinones/pharmacology , alpha-MSH/pharmacology
14.
Exp Dermatol ; 23(3): 204-6, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24499351

ABSTRACT

Autophagy degrades cellular components and organelles through a cooperative process involving autophagosomes and lysosomes. Although autophagy is known to mainly regulate the turnover of cellular components, the role of autophagy in melanogenesis has not been well addressed. Here, we show that inhibition of autophagy suppresses the antimelanogenesis activity of resveratrol (RSV), a well-known antimelanogenic agent. RSV strongly increased autophagy in melanocytes. However, the depletion of ATG5 significantly suppressed RSV-mediated antimelanogenesis as well as RSV-induced autophagy in melanocytes. Moreover, suppression of ATG5 retrieved the RSV-mediated downregulation of tyrosinase and TRP1 in α-MSH-treated cells. Most importantly, electron microscopy analysis revealed that autophagosomes engulfed melanin or melanosomes after combined treatment of α-MSH and RSV. Taken together, these results suggest that RSV-mediated autophagy regulates melanogenesis.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Autophagy/drug effects , Melanins/biosynthesis , Melanocytes/drug effects , Stilbenes/pharmacology , alpha-MSH/pharmacology , Autophagy-Related Protein 5 , Cell Line, Tumor , Down-Regulation/drug effects , Humans , Melanocytes/metabolism , Melanocytes/ultrastructure , Melanosomes/ultrastructure , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , Monophenol Monooxygenase/metabolism , Resveratrol , Trypsin/metabolism
15.
Cell Biochem Funct ; 32(3): 229-35, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24037733

ABSTRACT

In the present study, we examined the effects of methanol extracts of Picrasma quassioides (MEPQ) on apoptosis in human cervical cancer cells. The results showed that MEPQ decreased the viability and induced caspase-dependent apoptosis in HEp-2 cells. MEPQ decreased specificity protein 1 (Sp1) in HEp-2 cells, whereas Sp1 mRNA was not changed. We found that MEPQ reduced Sp1 protein through proteasome-dependent protein degradation, but not the inhibition of protein synthesis. Also, MEPQ increased the expressions of Bad and truncated Bid (t-Bid) but did not alter other Bcl-2 family members. The knock-down of Sp1 by both Sp1 interfering RNA and Mithramycin A, Sp1 specific inhibitor clearly increased Bad and t-Bid expression to decrease cell viability and induce apoptosis. In addition, MEPQ inhibited cell viability and induced apoptotic cell death through the modulation of Sp1 in KB cells. These results suggest that MEPQ may be a potential anticancer agent for human cervical cancer.


Subject(s)
Apoptosis/drug effects , Picrasma , Plant Extracts/pharmacology , Sp1 Transcription Factor/metabolism , Uterine Cervical Neoplasms/metabolism , BH3 Interacting Domain Death Agonist Protein/metabolism , Cell Line, Tumor/drug effects , Cell Proliferation/drug effects , Cell Survival/drug effects , Female , Humans , Methanol , Plicamycin/analogs & derivatives , Plicamycin/metabolism , Proteasome Endopeptidase Complex/metabolism , RNA, Small Interfering/genetics , Solvents , Sp1 Transcription Factor/genetics , Uterine Cervical Neoplasms/pathology , bcl-Associated Death Protein/metabolism
16.
Oral Oncol ; 50(3): 189-95, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24309154

ABSTRACT

OBJECTIVES: Dibenzylideneacetone (DBA), a curcumin analogue that has anti-cancer activity in a variety of tumor cells. In this study, we investigated the apoptotic effects of DBA and its molecular mechanism in human mucoepidermoid carcinoma (MEC) cell lines and tumor xenografts. MATERIAL AND METHODS: The apoptotic effects and related molecular mechanisms of DBA on MEC cell lines were evaluated using cell viability assay, DAPI staining, Western blot analysis, reverse transcriptase-polymerase chain reaction (RT-PCR) and Dual-luciferase Reporter Assay. The anti-tumor activity using in vivo were determined by Nude mouse xenograft assay and histopathological examination. RESULTS: DBA decreased cell viability and induced apoptosis in MEC cells. These events were accompanied by inhibition of specificity protein 1 (Sp1). DBA did not induce major changes in Sp1 mRNA and promoter activity. Furthermore, inhibition of protein synthesis by cycloheximide demonstrated that DBA decreased Sp1 protein stability, but DBA did not attenuate phosphorylation of eIF4E. DBA also increased Bim and truncated Bid (t-Bid) via Sp1. Finally, DBA exhibited significant anti-tumor activity in athymic nude mice xenografts bearing MC-3 cells by regulating Sp1, Bim and t-Bid without any systemic toxicity. CONCLUSION: These results elucidate a crucial apoptotic mechanism of DBA and suggest that DBA may be a potent anticancer drug candidate for MEC.


Subject(s)
Carcinoma, Mucoepidermoid/metabolism , Pentanones/pharmacology , Sp1 Transcription Factor/metabolism , Animals , Apoptosis/drug effects , Apoptosis Regulatory Proteins/metabolism , BH3 Interacting Domain Death Agonist Protein/metabolism , Bcl-2-Like Protein 11 , Biomarkers, Tumor/metabolism , Cell Line, Tumor , Cycloheximide/pharmacology , Eukaryotic Initiation Factor-4E/metabolism , Female , Humans , Membrane Proteins/metabolism , Mice , Mice, Nude , Neoplasms, Experimental , Protein Synthesis Inhibitors/pharmacology , Proto-Oncogene Proteins/metabolism , Sp1 Transcription Factor/antagonists & inhibitors , Xenograft Model Antitumor Assays
17.
Exp Ther Med ; 7(1): 228-232, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24348795

ABSTRACT

Fucoidan is a sulfated polysaccharide present in brown algae that has been identified to exhibit multiple biological effects. In this study, the apoptotic effects of fucoidan in MC3 human mucoepidermoid carcinoma (MEC) cells were investigated. The apoptotic effects of fucoidan on MC3 MEC cells were evaluated by cell proliferation assay, 4',6-diamidino-2-phenylindole staining and western blot analysis. The results showed that fucoidan decreased cell proliferation and induced caspase-dependent apoptosis in MC3 MEC cells. Fucoidan downregulated the phosphorylation of extracellular signal-regulated kinase (ERK) 1/2, whereas phospho-p38 mitogen-activated protein kinase or phospho-c-Jun NH2-terminal kinase (JNK) levels were not altered. In addition, fucoidan significantly decreased the expression levels of myeloid cell leukemia-1 (Mcl-1). These results suggest that fucoidan is able to modulate the ERK1/2 pathway and thereby regulate Mcl-1 protein expression and induce apoptosis in MC3 MEC cells. Therefore, fucoidan may be a promising agent for the treatment of human MEC.

18.
FEBS Lett ; 587(24): 3955-60, 2013 Dec 11.
Article in English | MEDLINE | ID: mdl-24188823

ABSTRACT

Autophagy is a cooperative process between autophagosomes and lysosomes that degrades cellular organelles. Although autophagy regulates the turnover of cellular components, its role in melanogenesis is not clearly established. Previously, we reported that ARP101 induces autophagy in various cancer cells. Here, we show that ARP101 inhibits melanogenesis by regulation of autophagy. ARP101 inhibited α-MSH-stimulated melanin synthesis and suppressed the expression of tyrosinase and TRP1 in immortalized mouse melanocytes. ARP101 also induced autophagy in melanocytes. Knockdown of ATG5 reduced both anti-melanogenic activity and autophagy mediated by ARP101 in α-MSH treated melanocytes. Electron microscopy analysis further revealed that autophagosomes engulf melanin or melanosome in α-MSH and ARP101-treated cells. Collectively, our results suggest that ARP101 inhibits α-MSH-stimulated melanogenesis through the activation of autophagy in melanocytes.


Subject(s)
Autophagy/drug effects , Cell Differentiation/drug effects , Melanocytes/drug effects , Sulfonamides/pharmacology , alpha-MSH/pharmacology , Animals , Autophagy/genetics , Autophagy-Related Protein 5 , Cell Differentiation/genetics , Cells, Cultured , Down-Regulation/drug effects , Gene Expression Regulation/drug effects , Melanocytes/metabolism , Melanocytes/physiology , Mice , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , Monophenol Monooxygenase/genetics , Monophenol Monooxygenase/metabolism , Oxidoreductases/genetics , Oxidoreductases/metabolism
19.
Biochem Biophys Res Commun ; 442(3-4): 165-70, 2013 Dec 13.
Article in English | MEDLINE | ID: mdl-24269817

ABSTRACT

Autophagy is a cellular degradation process for cellular aggregates and unneeded cellular compartments including damaged mitochondria, ER, and peroxisomes. Melanosome is cellular organelle that is the cellular site of generation, storage and transports of melanin in melanocytes. Despite potential importance of autophagy, the role of autophagy in melanogenesis and melanosome autophagy are largely unknown. In here, we identified 3'-hydroxydaidzein (3'-ODI) as an autophagy inducer from a phytochemical library screening. Treatment with 3'-ODI significantly reduced α-MSH-mediated melanogenesis but efficiently increased autophagy both in melanoma cells and melanocytes. Furthermore, inhibition of autophagy significantly reduced the anti-melanogenic effects of 3'-ODI in α-MSH-stimulated melanoma cells. Taken together, these results suggest that autophagy mediates anti-melanogenic activity of 3'-ODI.


Subject(s)
Autophagy/drug effects , Isoflavones/pharmacology , Melanins/antagonists & inhibitors , Melanocytes/drug effects , Melanosomes/drug effects , Animals , Autophagy/genetics , Autophagy-Related Protein 5 , Cell Line, Tumor , Melanins/biosynthesis , Melanocytes/metabolism , Melanosomes/metabolism , Mice , Microtubule-Associated Proteins/antagonists & inhibitors , Microtubule-Associated Proteins/genetics , RNA Interference , alpha-MSH/pharmacology
20.
J Clin Biochem Nutr ; 53(2): 89-93, 2013 Sep.
Article in English | MEDLINE | ID: mdl-24062605

ABSTRACT

Mithramycin A (Mith) is an aureolic acid-type polyketide produced by various soil bacteria of the genus Streptomyces. Mith inhibits myeloid cell leukemia-1 (Mcl-1) to induce apoptosis in prostate cancer, but the molecular mechanism underlying this process has not been fully elucidated. The aim of this study was therefore to investigate the detailed molecular mechanism related to Mith-induced apoptosis in prostate cancer cells. Mith decreased the phosphorylation of mammalian target of rapamycin (mTOR) in both cell lines overexpressing phospho-mTOR compared to RWPE-1 human normal prostate epithelial cells. Mith significantly induced truncated Bid (tBid) and siRNA-mediated knock-down of Mcl-1 increased tBid protein levels. Moreover, Mith also inhibited the phosphorylation of mTOR on serine 2448 and Mcl-1, and increased tBid protein in prostate tumors in athymic nude mice bearing DU145 cells as xenografts. Thus, Mith acts as an effective tumor growth inhibitor in prostate cancer cells through the mTOR/Mcl-1/tBid signaling pathway.

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