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1.
Noncoding RNA Res ; 9(3): 876-886, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38586313

RESUMO

Although rare, there is ongoing research into biomarkers that predict the onset and recurrence of gastric cancer, particularly focusing on substances found in exosomes. Long non-coding RNAs (lncRNAs) have garnered attention for their potential in diagnosing gastric cancer. This study investigates the role of lncRNAs in gastric cancer, focusing on their presence in exosomes as potential biomarkers for the disease's onset and recurrence. We utilized the ArrayStar Human LncRNA array 2.0 to analyze lncRNA expression in tissues from early-stage gastric cancer patients. Our analysis highlighted LINC00853, which was significantly upregulated in cancer tissues and implicated in promoting epithelial-mesenchymal transition via the MAP17/PDZK1/AKT pathway. Functional studies on AGS and MKN74 gastric cancer cell lines demonstrated that LINC00853 facilitates cell proliferation, invasion, and migration. Additionally, RNA immunoprecipitation and electrophoretic mobility shift assays confirmed LINC00853 interaction with MAP17. Importantly, LINC00853 was also detected in exosomes from both patient samples and cell lines, and its downregulation led to decreased tumorigenicity in AGS cells. These findings suggest that both cellular and exosomal LINC00853 contribute to gastric cancer pathogenesis and may serve as valuable biomarkers for the disease.

2.
Photodermatol Photoimmunol Photomed ; 39(2): 147-154, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36461152

RESUMO

BACKGROUND/PURPOSE: The pathogenesis of chronic actinic dermatitis (CAD) is more complicated than other photodermatoses. However, the relationship between the clinical severity of CAD and the offending photocontact or contact allergens or both, and the correlations of CAD immunopathogenesis with the immunoregulatory molecules involved in adaptive immunity are yet to be investigated. METHODS: We performed phototesting with broad-spectrum ultraviolet (UV) B, UVA, and visible light to establish the presence of photosensitivity in 121 patients with CAD, together with photopatch and contact patch testing. Nine patients with CAD were selected according to their clinical severity score for CAD (CSS-CAD), and triple direct immunofluorescence analysis was performed with paraffin-embedded skin biopsy samples. RESULTS: As CSS-CAD was closely correlated with the multiplicity of photo(contact) allergens, particularly photoallergens, three or more photoallergens were detected in the severe CAD group (52.5%); less in the moderate group (32.8%); and only one in the mild group (14.8%; P = .025). In the groups showing greater severity of disease, the absolute numbers of IFN-γ+ , IL-17+ , CD4+, CD8+, common-γ chain receptor (common-γCR)+ , and CD69+ tissue-resident memory cells increased on average; there was also an increase in the CD4+/CD8+ cell ratio, with the more severely affected groups. However, the levels of TNF-α+ and FoxP3+ regulatory T (Treg) cells and the mean IL-17/IFN-γ cell ratio decreased in the more severely affected CSS-CAD subgroups. CONCLUSIONS: Based on the clinical analysis and immunopathogenic results, avoidance of excessive sun exposure, and topical and systemic blocking agents for photo(contact) allergens are recommended. Additionally, conventional immunomodulators and emerging agents including JAK-STAT inhibitors may be administered for CAD treatment in the future.


Assuntos
Transtornos de Fotossensibilidade , Linfócitos T Reguladores , Células Th17 , Humanos , Imunidade Adaptativa , Alérgenos/uso terapêutico , Interleucina-17 , Transtornos de Fotossensibilidade/patologia , Linfócitos T Citotóxicos/patologia , Linfócitos T Reguladores/patologia , Receptores de Antígenos de Linfócitos T gama-delta
5.
Cancers (Basel) ; 14(10)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35625973

RESUMO

DKK1 inhibits the canonical Wnt signaling pathway that is known to be involved in various cancers. However, whether DKK1 acts as an oncogene or tumor suppressor gene remains controversial. Furthermore, the DKK1-regulating mechanism in gastric cancer has not yet been defined. The aim of this study was to explore whether the ultraconserved region UC.145 regulates epigenetic changes in DKK1 expression in gastric cancer. Microarray analysis revealed that UC.145 exhibited the highest binding affinity to EZH2, a histone methyltransferase. The effects of UC.145 inactivation were assessed in gastric cancer cell lines using siRNA. The results indicated that UC.145 triggers DKK1 methylation via interaction with EZH2 and is involved in the canonical Wnt signaling pathway. Additionally, interaction between UC.145 and another long non-coding RNA adjacent to DKK1, PRKG1-AS1, induced a synergistic effect on Wnt signaling. The regulation of these three genes was closely associated with patient overall survival. Inactivation of UC.145 induced apoptosis and inhibited the growth and migratory, invasive, and colony-forming abilities of gastric cancer cells. The study findings provide insights into Wnt signaling in gastric cancer and support UC.145 as a potential novel predictive biomarker for the disease.

6.
Yonsei Med J ; 62(2): 118-128, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33527791

RESUMO

PURPOSE: HOX transcript antisense intergenic RNA (HOTAIR), as a long non-coding RNA, has been reported to regulate carcinogenesis by epigenetic mechanism in various cancers. Protocadherin 10 (PCDH10) is one of the well-known tumor suppressor genes, and is frequently methylated in gastric cancers (GC). We aimed to investigate the detailed pathway of how HOTAIR contributes to the target gene in gastric carcinogenesis. MATERIALS AND METHODS: We investigated the mechanism of HOTAIR on carcinogenesis and metastasis of GC. Methylation-specific PCR was performed to identify the interaction between HOTAIR and PCDH10. In addition, we investigated the interaction between miR-148b and HOTAIR by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. RESULTS: The expression of HOTAIR was significantly upregulated in GC tissues (p<0.05) and GC cell lines (p<0.01), while PCDH10 was downregulated in GC tissues (p<0.05). The knockdown of HOTAIR (si-HOTAIR1 and 2) significantly upregulated the mRNA/protein expression of PCDH10 and reduced the methylation of PCDH10 compared to the control in MKN 28 and MKN 74. Si-HOTAIR1 and 2 significantly reduced DNA methyltransferase 1 (DNMT1) expression, and overexpression of HOTAIR increased DNMT1 expression. In RIP, we found that miR-148b interacted with HOTAIR. Si-HOTAIRs increased miR-148b expression, and miR-148b mimic inversely reduced HOTAIR expression. Si-HOTAIRs and miR-148b mimic reduced DNMT1 expression and increased PCDH10 expression compared to the control. CONCLUSION: This study demonstrated that HOTAIR interacts with miR-148b and DNMT1, eventually leading to PCDH10 methylation, which contributes to the progression of GC. Our findings provide a better understanding for detailed pathway of HOTAIR in epigenetic mechanism of GC.


Assuntos
Adenocarcinoma/genética , Caderinas/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Metilação de DNA/genética , Genes Supressores de Tumor , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , Neoplasias Gástricas/genética , Apoptose/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica , Protocaderinas , Neoplasias Gástricas/patologia
7.
Yonsei Med J ; 61(11): 923-934, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33107235

RESUMO

PURPOSE: The mechanisms of Wnt/ß-catenin pathway signaling and abnormal expression of tumor suppressor genes is not well known in gastric cancer (GC). Long non-coding RNA (lncRNA) has recently been identified as a possible link therein. In this study, we investigated the role of lung cancer associated transcript 1 (LUCAT1) in GC. MATERIALS AND METHODS: The expression of LUCAT1 in GC cell lines and 100 tissue samples was examined by qRT-PCR. Two different siRNAs were used for knockdown of LUCAT1 expression. Cell viability was assessed by MTT assay. To analyze metastasis, scratch wound-healing assay, a Matrigel invasion assay, and colony formation assay were performed. Apoptosis was analyzed by PI/Annexin-V staining. To check the methylation status in tumor suppressor genes, methylation-specific PCR was carried out. Western blot was performed to detect epithelial-mesenchymal transition and apoptosis markers upon silencing of LUCAT1 (siLUCAT1). RESULTS: LUCAT1 expression in GC cell lines and tissues was significantly elevated, compared to that in normal gastric cells and adjacent non-tumor tissues (p<0.001). Two different siRNAs for LUCAT1 reduced cell proliferation, invasion, and migration, compared to siCT (p<0.05), and these reductions were restored by pcDNA-LUCAT1 (p<0.05). siLUCAT1 elicited upregulation of the expression of CXXC4 and SFRP2. The expression of H3K27me3 was reduced by siLUCAT1, and this reduction was correlated with methylation of CXXC4 and SFRP2. Inhibition of LUCAT1 up-regulated EZH2 expression and resulted in demethylation of CXXC4 and SFRP2 through the Wnt/ß-catenin signaling pathway. CONCLUSION: We concluded that LUCAT1 induces methylation of CXXC4 and SFRP2, thereby regulating Wnt/ß-catenin signaling in GC.


Assuntos
Proteínas de Ligação a DNA/genética , Genes Supressores de Tumor , Proteínas de Membrana/genética , Invasividade Neoplásica/genética , RNA Longo não Codificante/metabolismo , Neoplasias Gástricas/genética , Fatores de Transcrição/genética , Apoptose/genética , Biomarcadores Tumorais/genética , Proliferação de Células/genética , Sobrevivência Celular , Proteínas de Ligação a DNA/metabolismo , Regulação para Baixo , Transição Epitelial-Mesenquimal , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Pulmonares/genética , Proteínas de Membrana/metabolismo , RNA Longo não Codificante/genética , RNA Interferente Pequeno/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/patologia , Fatores de Transcrição/metabolismo , Regulação para Cima , Via de Sinalização Wnt
8.
Proc Natl Acad Sci U S A ; 116(49): 24620-24629, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31732666

RESUMO

Wnt signaling through both canonical and noncanonical pathways plays a core role in development. Dysregulation of these pathways often causes cancer development and progression. Although the pathways independently contribute to the core processes, a regulatory molecule that commonly activates both of them has not yet been reported. Here, we describe a long noncoding RNA (lncRNA), HERES, that epigenetically regulates both canonical and noncanonical Wnt signaling pathways in esophageal squamous cell carcinoma (ESCC). For this study, we performed RNA-seq analysis on Korean ESCC patients and validated these results on a larger ESCC cohort to identify lncRNAs commonly dysregulated in ESCCs. Six of the dysregulated lncRNAs were significantly associated with the clinical outcomes of ESCC patients and defined 4 ESCC subclasses with different prognoses. HERES reduction repressed cell proliferation, migration, invasion, and colony formation in ESCC cell lines and tumor growth in xenograft models. HERES appears to be a transacting factor that regulates CACNA2D3, SFRP2, and CXXC4 simultaneously to activate Wnt signaling pathways through an interaction with EZH2 via its G-quadruple structure-like motif. Our results suggest that HERES holds substantial potential as a therapeutic target for ESCC and probably other cancers caused by defects in Wnt signaling pathways.


Assuntos
Proteína Potenciadora do Homólogo 2 de Zeste/genética , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , RNA Longo não Codificante/metabolismo , Via de Sinalização Wnt/genética , Canais de Cálcio/genética , Linhagem Celular Tumoral , Metilação de DNA/genética , Proteínas de Ligação a DNA/genética , Conjuntos de Dados como Assunto , Progressão da Doença , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Epigênese Genética , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/mortalidade , Carcinoma de Células Escamosas do Esôfago/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , RNA Longo não Codificante/genética , RNA Interferente Pequeno/metabolismo , RNA-Seq , Fatores de Transcrição/genética , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Gut Liver ; 13(4): 421-429, 2019 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-30970439

RESUMO

Background/Aims: Gastric cancer is one of the most common malignant tumors worldwide with poor prognosis due to a lack of effective treatment modalities. Recent research showed that a long noncoding RNA named N-BLR modulates the epithelial-to-mesenchymal transition (EMT) process in colorectal cancer. However, the biological role of N-BLR in gastric cancer still remains to be explored. The aim of this study was to investigate the possibility of N-BLR as an EMT modulator in gastric cancer. Methods: The expression of N-BLR was measured by quantitative polymerase chain reaction in fresh gastric cancer tissue, paired adjacent normal tissues and cell lines. Fresh gastric tissues, paired samples obtained by surgery and clinical data were collected prospectively. Knockdown of N-BLR was induced by small interfering RNA (siRNAs). Cell number and viability were assessed after treatment with siRNAs. The ability of N-BLR to promote metastasis was measured using migration and invasion assays. Additionally, an inverse correlation between N-BLR and miR-200c was measured by TaqMan microRNA assays. Western blotting was performed to detect EMT and apoptosis markers upon knockdown of N-BLR. Results: N-BLR expression was significantly elevated in gastric cancer cell lines and tissues compared to that in a normal gastric cell line and adjacent normal tissues (p<0.01). Two different siRNAs significantly reduced cell proliferation of gastric cancer cells compared to the siCT. siRNAs for N-BLR significantly suppressed migration and invasion in AGS and MKN28 cells. N-BLR expression was inversely correlated with miR-200c, which is known to regulate EMT. Conclusions: In this study, we confirmed N-BLR as a regulator of the EMT process in gastric cancer.


Assuntos
Adenocarcinoma/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , RNA Longo não Codificante/genética , Neoplasias Gástricas/genética , Adenocarcinoma/patologia , Idoso , Linhagem Celular Tumoral , Feminino , Técnicas de Silenciamento de Genes , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Metástase Neoplásica/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/patologia
10.
Front Oncol ; 9: 145, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30949448

RESUMO

Metabolic rewiring has been recognized as an important feature to the progression of cancer. However, the essential components and functions of lipid metabolic networks in breast cancer progression are not fully understood. In this study, we investigated the roles of altered lipid metabolism in the malignant phenotype of breast cancer. Using a spheroid-induced epithelial-mesenchymal transition (EMT) model, we conducted multi-layered lipidomic and transcriptomic analysis to comprehensively describe the rewiring of the breast cancer lipidome during the malignant transformation. A tremendous homeostatic disturbance of various complex lipid species including ceramide, sphingomyelin, ether-linked phosphatidylcholines, and ether-linked phosphatidylethanolamine was found in the mesenchymal state of cancer cells. Noticeably, polyunsaturated fatty acids composition in spheroid cells was significantly decreased, accordingly with the gene expression patterns observed in the transcriptomic analysis of associated regulators. For instance, the up-regulation of SCD, ACOX3, and FADS1 and the down-regulation of PTPLB, PECR, and ELOVL2 were found among other lipid metabolic regulators. Significantly, the ratio of C22:6n3 (docosahexaenoic acid, DHA) to C22:5n3 was dramatically reduced in spheroid cells analogously to the down-regulation of ELOVL2. Following mechanistic study confirmed the up-regulation of SCD and down-regulation of PTPLB, PECR, ELOVL2, and ELOVL3 in the spheroid cells. Furthermore, the depletion of ELOVL2 induced metastatic characteristics in breast cancer cells via the SREBPs axis. A subsequent large-scale analysis using 51 breast cancer cell lines demonstrated the reduced expression of ELOVL2 in basal-like phenotypes. Breast cancer patients with low ELOVL2 expression exhibited poor prognoses (HR = 0.76, CI = 0.67-0.86). Collectively, ELOVL2 expression is associated with the malignant phenotypes and appear to be a novel prognostic biomarker in breast cancer. In conclusion, the present study demonstrates that there is a global alteration of the lipid composition during EMT and suggests the down-regulation of ELOVL2 induces lipid metabolism reprogramming in breast cancer and contributes to their malignant phenotypes.

11.
J Gastroenterol Hepatol ; 34(1): 84-91, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30221400

RESUMO

BACKGROUND AND AIM: A high yield of biopsy is mandatory to perform molecular genetic research with endoscopically obtained gastric cancer tissues. We evaluated whether probe-based confocal laser endomicroscopy (pCLE) can increase the yield of endoscopic biopsy for gastric cancer compared with white light endoscopy (WLE). METHODS: All lesions in the pCLE and WLE groups were initially evaluated through WLE. In the pCLE group, lesions were further examined through pCLE. In the pilot study, five and three biopsy specimens were obtained for histopathological examination and tumor marker analysis, respectively. In the confirmatory study, six biopsy specimens for histopathological evaluation were obtained. RESULTS: A total of 30 gastric cancers and 61 undifferentiated-type gastric cancers were analyzed in the pilot and confirmatory studies, respectively. The proportion of cancer cells in biopsy samples of poorly differentiated adenocarcinoma or signet ring cell carcinoma was higher in the pCLE group than in the WLE group in both the pilot and confirmatory studies (pilot: median proportion, 65% vs 30%, P = 0.010; confirmatory: mean ± standard deviation, 49.5 ± 29.3 vs 29.3 ± 13.7, P = 0.002). The expression ratio of tumor markers including carcinoembryonic antigen, GW112, HOX transcript antisense RNA, and H19 tended to be higher in the pCLE group than in the WLE group. CONCLUSION: Probe-based confocal laser endomicroscopy-targeted biopsy provided superior results in terms of the proportion of cancer cells in biopsy samples compared with WLE-targeted biopsy in gastric cancer with undifferentiated histology.


Assuntos
Adenocarcinoma/patologia , Carcinoma de Células em Anel de Sinete/patologia , Endoscopia Gastrointestinal/métodos , Neoplasias Gástricas/patologia , Adenocarcinoma/metabolismo , Adulto , Idoso , Antígeno Carcinoembrionário/metabolismo , Carcinoma de Células em Anel de Sinete/metabolismo , Diferenciação Celular , Feminino , Fator Estimulador de Colônias de Granulócitos/metabolismo , Humanos , Biópsia Guiada por Imagem/métodos , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , Gradação de Tumores , Projetos Piloto , RNA Longo não Codificante/metabolismo , Neoplasias Gástricas/metabolismo
12.
Cancer Lett ; 417: 47-57, 2018 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-29247823

RESUMO

Available targeted therapies for esophageal squamous cell carcinoma (ESCC) are limited; thus, further genetic and epigenetic studies are needed. Recently, many long noncoding RNAs (lncRNAs) have been reported to be involved in various cancers. Here, we investigated whether the lncRNA LUCAT1 was related to the carcinogenesis of ESCC based on previous studies in lung cancer. LUCAT1 was significantly upregulated in ESCC cell lines and cancer tissue compared with normal cells and adjacent normal tissues. LUCAT1 knockdown reduced cell proliferation, induced apoptosis, and upregulated tumor-suppressor genes by reducing DNA methylation in KYSE-30 cells. Moreover, LUCAT1 siRNA reduced DNA methyltransferase 1 (DNMT1) protein levels without affecting transcription. Patients with high LUCAT1 expression had significantly lower survival rates than patients with low LUCAT1 expression. Our results thus suggest that LUCAT1 regulates the stability of DNMT1 and inhibits the expression of tumor suppressors through DNA methylation, leading to the formation and metastasis of ESCC. We identified LUCAT1 as a potential target for drug development and as a biomarker for ESCC.


Assuntos
Carcinogênese/genética , Carcinoma de Células Escamosas/genética , DNA (Citosina-5-)-Metiltransferase 1/genética , Neoplasias Esofágicas/genética , Regulação Neoplásica da Expressão Gênica , RNA Longo não Codificante/genética , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Metilação de DNA/genética , Estabilidade Enzimática , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Interferência de RNA , Ubiquitinação
13.
PLoS One ; 11(2): e0148818, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26870956

RESUMO

Generally, cancer stem cells have epithelial-to-mesenchymal-transition characteristics and other aggressive properties that cause metastasis. However, there have been no confident markers for the identification of cancer stem cells and comparative methods examining adherent and sphere cells are widely used to investigate mechanism underlying cancer stem cells, because sphere cells have been known to maintain cancer stem cell characteristics. In this study, we conducted a meta-analysis that combined gene expression profiles from several studies that utilized tumorsphere technology to investigate tumor stem-like breast cancer cells. We used our own gene expression profiles along with the three different gene expression profiles from the Gene Expression Omnibus, which we combined using the ComBat method, and obtained significant gene sets using the gene set analysis of our datasets and the combined dataset. This experiment focused on four gene sets such as cytokine-cytokine receptor interaction that demonstrated significance in both datasets. Our observations demonstrated that among the genes of four significant gene sets, six genes were consistently up-regulated and satisfied the p-value of < 0.05, and our network analysis showed high connectivity in five genes. From these results, we established CXCR4, CXCL1 and HMGCS1, the intersecting genes of the datasets with high connectivity and p-value of < 0.05, as significant genes in the identification of cancer stem cells. Additional experiment using quantitative reverse transcription-polymerase chain reaction showed significant up-regulation in MCF-7 derived sphere cells and confirmed the importance of these three genes. Taken together, using meta-analysis that combines gene set and network analysis, we suggested CXCR4, CXCL1 and HMGCS1 as candidates involved in tumor stem-like breast cancer cells. Distinct from other meta-analysis, by using gene set analysis, we selected possible markers which can explain the biological mechanisms and suggested network analysis as an additional criterion for selecting candidates.


Assuntos
Neoplasias da Mama/patologia , Células-Tronco Neoplásicas/metabolismo , Transcriptoma , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Feminino , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos
14.
Cell Res ; 25(6): 707-25, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25952668

RESUMO

Receptor-interacting protein kinase-3 (RIP3 or RIPK3) is an essential part of the cellular machinery that executes "programmed" or "regulated" necrosis. Here we show that programmed necrosis is activated in response to many chemotherapeutic agents and contributes to chemotherapy-induced cell death. However, we show that RIP3 expression is often silenced in cancer cells due to genomic methylation near its transcriptional start site, thus RIP3-dependent activation of MLKL and downstream programmed necrosis during chemotherapeutic death is largely repressed. Nevertheless, treatment with hypomethylating agents restores RIP3 expression, and thereby promotes sensitivity to chemotherapeutics in a RIP3-dependent manner. RIP3 expression is reduced in tumors compared to normal tissue in 85% of breast cancer patients, suggesting that RIP3 deficiency is positively selected during tumor growth/development. Since hypomethylating agents are reasonably well-tolerated in patients, we propose that RIP3-deficient cancer patients may benefit from receiving hypomethylating agents to induce RIP3 expression prior to treatment with conventional chemotherapeutics.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Metilação de DNA , Necrose/tratamento farmacológico , Necrose/patologia , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Animais , Neoplasias da Mama/genética , Sobrevivência Celular/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Necrose/genética , Necrose/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/deficiência , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
15.
J Invest Dermatol ; 135(8): 2021-2030, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25748555

RESUMO

Toxic epidermal necrolysis (TEN) is a severe adverse drug reaction involving extensive keratinocyte death in the epidermis. Histologically, the skin from TEN patients exhibits separation at the dermo-epidermal junction and accompanying necrosis of epidermal keratinocytes. Receptor-interacting protein kinase-3 (RIP3 or RIPK3) is an essential part of the cellular machinery that executes "programmed", or "regulated", necrosis and has a key role in spontaneous cell death and inflammation in keratinocytes under certain conditions. Here we show that RIP3 expression is highly upregulated in skin sections from TEN patients and may therefore contribute to the pathological damage in TEN through activation of programmed necrotic cell death. The expression level of mixed lineage kinase domain-like protein (MLKL), a key downstream component of RIP3, was not significantly different in skin lesions of TEN. However, elevated MLKL phosphorylation was observed in the skin from TEN patients, indicating the presence of RIP3-dependent programmed necrosis. Importantly, in an in vitro model of TEN, dabrafenib, an inhibitor of RIP3, prevented RIP3-mediated MLKL phosphorylation and decreased cell death. Results from this study suggest that the high expression of RIP3 in keratinocytes from TEN patients potentiates MLKL phosphorylation/activation and necrotic cell death. Thus, RIP3 represents a potential target for treatment of TEN.


Assuntos
Epiderme/metabolismo , Epiderme/patologia , Proteínas Quinases/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Síndrome de Stevens-Johnson/metabolismo , Síndrome de Stevens-Johnson/patologia , Regulação para Cima/fisiologia , Adulto , Idoso de 80 Anos ou mais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Biópsia , Células Cultivadas , Criança , Pré-Escolar , Humanos , Imidazóis/farmacologia , Técnicas In Vitro , Junções Intercelulares/fisiologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Queratinócitos/patologia , Pessoa de Meia-Idade , Necrose/metabolismo , Necrose/patologia , Oximas/farmacologia , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Pele/metabolismo , Pele/patologia
16.
Ann Plast Surg ; 74(4): 488-95, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23851370

RESUMO

Capsular contracture is one of the most common complications resulting from implants placed during mammoplasty and rhinoplasty, and there is no definitive solution or a method for preventing it. Recent reports suggest that botulinum toxin A (BoTA) is effective at reducing keloid scars clinically. Peri-implant capsules are histologically similar to keloid scars and hypertrophic scars. Therefore, we hypothesized that BoTA may reduce peri-implant capsule formation.To test our hypothesis, we divided 24 male Sprague-Dawley rats into an experiment group and a control group. We created two 15 × 15-mm subpanniculus pockets in each rat. Botulinum toxin A (0.5 mL; 5 U) was injected into the carnosa layer of the experimental group's pockets and 0.5 mL normal saline was similarly injected in the control group. Hemispherical silicone implants, 15 mm in diameter, were inserted into the pockets. After 6 weeks, the peri-implant capsule was excised and examined by histologic evaluation, immunohistochemical stain, scanning electron microscope, and real-time polymerase chain reaction.Capsular thickness, number of inflammatory cells, number of vessels, and transforming growth factor ß1 expression were reduced in the experimental group compared to the control group (P < 0.01). The experimental group's collagen pattern was loose and well organized. The total myofibroblast content was lower in the experimental group than in the control group; however, this difference was not statistically significant (P = 0.32). Additionally, the experimental group had a smaller fibrosis index than the control group (P < 0.05).Our results suggest that BoTA may provide an alternative treatment for reducing capsule formation and preventing contracture, and further studies may reveal the mechanism of action.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Contratura Capsular em Implantes/prevenção & controle , Fármacos Neuromusculares/uso terapêutico , Próteses e Implantes , Géis de Silicone , Animais , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento
17.
Oncotarget ; 5(12): 4438-51, 2014 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-24970805

RESUMO

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths worldwide. High mortality from HCC is mainly due to widespread prevalence and the lack of effective treatment, since systemic chemotherapy is ineffective, while the targeted agent Sorafenib extends median survival only briefly. The steroidal saponin 20(S)-ginsenoside Rg3 from Panax ginseng C.A. Meyer is proposed to chemosensitize to various therapeutic drugs through an unknown mechanism. Since autophagy often serves as cell survival mechanism in cancer cells exposed to chemotherapeutic agents, we examined the ability of Rg3 to inhibit autophagy and chemosensitize HCC cell lines to doxorubicin in vitro. We show that Rg3 inhibits late stage autophagy, possibly through changes in gene expression. Doxorubicin-induced autophagy plays a protective role in HCC cells, and therefore Rg3 treatment synergizes with doxorubicin to kill HCC cell lines, but the combination is relatively nontoxic in normal liver cells. In addition, Rg3 was well-tolerated in mice and synergized with doxorubicin to inhibit tumor growth in HCC xenografts in vivo. Since novel in vivo inhibitors of autophagy are desirable for clinical use, we propose that Rg3 is such a compound, and that combination therapy with classical chemotherapeutic drugs may represent an effective therapeutic strategy for HCC treatment.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Doxorrubicina/farmacologia , Ginsenosídeos/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Autofagia , Feminino , Ginsenosídeos/administração & dosagem , Humanos , Masculino
18.
J Sci Food Agric ; 93(3): 587-92, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22903784

RESUMO

BACKGROUND: The increase in drug-resistant bacteria and the ban on antibiotic growth promoters worldwide make the search for novel means of preventing bacterial infection and promoting growth performance imperative. In this sense, antimicrobial peptides are thought to be ideal candidates owing to their antimicrobial properties, broad spectrum of activity and low propensity for development of bacterial resistance. The aim of the present study was to investigate the effect of dietary supplementation with antimicrobial peptide-P5 (AMP-P5) on weanling pig nutrition. RESULTS: A total of 240 weanling pigs were allotted to four treatments on the basis of initial body weight. There were four replicates in each treatment, with 15 pigs per replicate. Dietary treatments were negative control (NC, basal diet without antimicrobial), positive control (PC, basal diet + 1.5 g kg(-1) apramycin), basal diet with 40 mg kg(-1) AMP-P5 (P5-40) and basal diet with 60 mg kg(-1) AMP-P5 (P5-60). Pigs fed the PC or P5-60 diet showed improved (P < 0.05) overall growth performance, apparent total tract digestibility of dry matter, crude protein and gross energy and reduced (P < 0.05) faecal and intestinal coliforms compared with pigs fed the NC diet. CONCLUSION: The results obtained in this study indicate that dietary supplementation with 60 mg kg(-1) AMP-P5 has the potential to improve the growth performance and apparent total tract digestibility of nutrients and reduce coliforms in weanling pigs.


Assuntos
Anti-Infecciosos/administração & dosagem , Peptídeos Catiônicos Antimicrobianos/administração & dosagem , Digestão/efeitos dos fármacos , Fezes/microbiologia , Intestinos/microbiologia , Sus scrofa/crescimento & desenvolvimento , Animais , Peptídeos Catiônicos Antimicrobianos/química , Suplementos Nutricionais , Mucosa Intestinal/metabolismo , Intestinos/anatomia & histologia , Peptídeos/administração & dosagem , Sus scrofa/metabolismo , Sus scrofa/microbiologia , Desmame
19.
Am J Chin Med ; 40(1): 187-202, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22298458

RESUMO

Administration of mountain ginseng (MG) extract can restore advanced cancer to a normal state. To elucidate the mechanism by which MG extract prevents the progression of lung cancer, the processes of proliferation and death of lung cancer cells (A549) were examined after treatment with MG extract. Butanol-extracted MG (BX-MG) showed a high inhibitory effect (IC(50) = 2 mg/ml) by attenuating proliferation and inducing apoptosis in lung cancer cells. By HPLC-UV analysis of BX-MG, ginsenosides, Rb1 was identified as the most abundant ginsenoside, followed by Rg1, Re, Rc and Rb2. BX-MG induced caspase-3 dependent apoptosis by inhibiting NF-κB. In addition, BX-MG activated p53 and p21, resulting in the attenuated proliferation of A549 cells. Reduced activity of the NF-κB promoter and increased activity of the p53 promoter indicate that BX-MG regulates apoptosis at the level of transcription in lung cancer cells. Furthermore, BX-MG blocked the nuclear translocation of RelA and the associated reduction in surviving. These results suggest that BX-MG inhibits lung cancer cell growth by activating tumor suppressors and inhibiting nuclear translocation of NF-κB.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Ginsenosídeos/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , NF-kappa B/metabolismo , Panax/química , Fitoterapia , Extratos Vegetais/uso terapêutico , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Transporte Biológico/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Ginsenosídeos/uso terapêutico , Humanos , Concentração Inibidora 50 , Neoplasias Pulmonares/metabolismo , Extratos Vegetais/farmacologia , Fator de Transcrição RelA/metabolismo , Proteína Supressora de Tumor p53/metabolismo
20.
Mol Biol Rep ; 39(2): 1087-93, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21584698

RESUMO

Autophagy is a membrane trafficking process involved in intracellular degradation and recycling in eukaryotic cells. DRAM2 (damage-regulated autophagy modulator 2) is a homologue of DRAM that regulates p53-mediated cell death. As its name implies, DRAM expression induces autophagy in a p53-dependent manner; however, the role of DRAM2 in autophagy is not clear. In this study, we report that DRAM2 expression contributes to autophagy induction. Overexpression of DRAM2 induces cytoplasmic GFP-LC3 punctuates, and increases the level of endogenous LC3-II. Moreover, the silencing of endogenous DRAM2 interferes with starvation-induced autophagy. Thus, we propose that DRAM2 as well as DRAM are involved in autophagy.


Assuntos
Autofagia/fisiologia , Proteínas de Membrana/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Autofagia/genética , Linhagem Celular , Proteínas de Fluorescência Verde/metabolismo , Humanos , Immunoblotting , Proteínas de Membrana/genética , Microscopia de Fluorescência , Proteínas Associadas aos Microtúbulos/metabolismo , Interferência de RNA
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