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Potamogeton crispus L. (P. crispus) is the type of a widely distributed perennial herbs, which is rich in rhodoxanthin. In this research work, five antioxidant indexes inâ vitro were selected to study the antioxidant activity of rhodoxanthin from P. crispus (RPC). A model of hydrogen peroxide (H2 O2 ) -induced oxidative damage in RAW264.7 cells was established to analyze the antioxidant effect and potential mechanism of RPC. The levels of ROS, MDA and the activities of oxidation related enzymes by H2 O2 were determined by enzyme linked immunosorbent assay (ELISA). The mRNA expression of Nrf-2, HO-1, SOD1 and SOD2 was measured by qRT-PCR assay. According to the results, RPC had free radical scavenging ability for 2, 2-diphenyl-1-trinitrohydrazine (DPPH), 2,2'-azinobis(3-ethylbenzo-thiazoline-6-sulfonic acid radical ion) (ABTS), hydroxyl radical and superoxide anion. RPC significantly decreased the level of MDA and ROS and LDH activity, while increased GSH level and activities of SOD, GSH-Px and CAT. It was showed that RPC could increase the mRNA expression of Nrf-2, HO-1, SOD1 and SOD2 in RAW264.7 cells in a dose-dependently manner. In summary, RPC treatment could effectively attenuate the H2 O2 -induced cell damage rate, and the mechanism is related to the reduction of H2 O2 induced oxidative stress and the activation of Nrf-2 pathway.
Assuntos
Antioxidantes , Potamogetonaceae , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Potamogetonaceae/genética , Potamogetonaceae/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase-1/metabolismo , Superóxido Dismutase-1/farmacologia , Estresse Oxidativo , Macrófagos , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/metabolismo , RNA Mensageiro/metabolismoRESUMO
Chemoresistance is a major obstacle faced by oesophageal cancer patients and is synonymous with a poor prognosis. MCL1 is a pivotal member of the anti-apoptotic Bcl-2 protein family, which has been found to play an important role in cell survival, proliferation, differentiation and chemoresistance. Thus, it might be an ideal target for treating oesophageal cancer patients. Although it is known that MCL1 is degraded via the ubiquitin-proteasome system, the deubiquitylating enzyme (DUB) responsible for stabilizing MCL1 remains elusive to date. Herein, we demonstrate that Ubiquitin-Specific Protease 20 (USP20) is a novel regulator of the apoptotic signaling pathway. Moreover, USP20 could regulate the deubiquitination of MCL1 to, in turn, regulate its stability. Increased expression of USP20 was correlated with increased levels of MCL1 protein in human patient samples. In addition, depletion of USP20 could increase the polyubiquitination of MCL1, thereby increasing the conversion rate of MCL1 and the sensitivity of cells to chemotherapy. Overall, our findings indicate that the USP20-MCL1 axis might play a key role in the apoptotic signaling pathway.
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Biomarcadores Tumorais/metabolismo , Resistencia a Medicamentos Antineoplásicos , Neoplasias Esofágicas/patologia , Regulação Neoplásica da Expressão Gênica , Proteína de Sequência 1 de Leucemia de Células Mieloides/química , Ubiquitina Tiolesterase/metabolismo , Ubiquitina/metabolismo , Antineoplásicos/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Movimento Celular , Proliferação de Células , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Células HEK293 , Humanos , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Complexo de Endopeptidases do Proteassoma , Estabilidade Proteica , Transdução de Sinais , Sorafenibe/farmacologia , Células Tumorais Cultivadas , Ubiquitina Tiolesterase/genética , UbiquitinaçãoRESUMO
Kupffer cells are liver resident macrophages and play critical role in fatty liver disease, yet the underlying mechanisms remain unclear. Here, we show that activation of G-protein coupled receptor 3 (GPR3) in Kupffer cells stimulates glycolysis and protects mice from obesity and fatty liver disease. GPR3 activation induces a rapid increase in glycolysis via formation of complexes between ß-arrestin2 and key glycolytic enzymes as well as sustained increase in glycolysis through transcription of glycolytic genes. In mice, GPR3 activation in Kupffer cells results in enhanced glycolysis, reduced inflammation and inhibition of high-fat diet induced obesity and liver pathogenesis. In human fatty liver biopsies, GPR3 activation increases expression of glycolytic genes and reduces expression of inflammatory genes in a population of disease-associated macrophages. These findings identify GPR3 activation as a pivotal mechanism for metabolic reprogramming of Kupffer cells and as a potential approach for treating fatty liver disease.
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Células de Kupffer , Hepatopatia Gordurosa não Alcoólica , Humanos , Animais , Camundongos , Células de Kupffer/metabolismo , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Glicólise , Obesidade/metabolismo , Camundongos Endogâmicos C57BL , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismoRESUMO
In the present study, the binding mechanism of vancomycin with human serum albumin (HSA) was determined. Upon addition of vancomycin to HSA, the fluorescence emission was quenched and the binding constant of vancomycin with HSA was found to be 6.05 × 10(3) M(-1) at 295 K, which corresponds to -2.16 × 10(4) J·mol(-1) of free energy. The conformation of HSA was altered upon binding of vancomycin with a decrease in α helix and an increase in ß sheets and random coils, suggesting partial unfolding of the secondary structure. Molecular docking experiments found that vancomycin binds strongly with HSA at the hydrophobic pocket through hydrogen bonding and van der Waals interactions. An average binding distance of 4.71 nm has been determined on the basis of the Förster resonance energy theory. It was demonstrated that vancomycin binding to HSA causes protein structural changes.
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Incompatibilidade de Medicamentos , Albumina Sérica/química , Vancomicina/química , Sítios de Ligação , Dicroísmo Circular , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Cinética , Simulação de Acoplamento Molecular , Ligação Proteica , Estrutura Secundária de Proteína , Soluções , Espectrometria de Fluorescência , TermodinâmicaRESUMO
INTRODUCTION: Pulmonary fibrosis (PF) is a fatal disease with a variable and unpredictable course. Effective clinical treatment for PF remains a challenge due to low drug accumulation in lungs and imbalanced polarization of pro/anti-fibrotic macrophages. OBJECTIVES: To identify the alteration of immunometabolism in the pulmonary macrophages and investigate the feasibility of specific inhibition of M2 activation of macrophages as an effective anti-PF strategy in vivo. METHODS: The high-content screening system was used to select lung-specific homing compounds that can modulate macrophage polarization. Imaging mass spectrometry (IMS) conjugated with chemical proteomics approach was conducted to explore the cells and proteins targeted by diphenyleneiodonium chloride (DPI). A bleomycin-induced fibrotic mouse model was established to examine the in vivo effect of DPI. RESULTS: Pulmonary macrophages of PF at late stage exhibited predominantly the M2 phenotype with decreased glycolysis metabolism. DPI was demonstrated to inhibit profibrotic activation of macrophages in the preliminary screening. Notably, IMS conjugated with chemical proteomics approach revealed DPI specifically targeted pulmonary macrophages, leading to the efficient protection from bleomycin-induced pulmonary fibrosis in mice. Mechanistically, DPI upregulated glycolysis and suppressed M2 programming in fibrosis mice, thus resulting in pro-fibrotic cytokine inhibition, hydroxyproline biosynthesis, and collagen deposition, with a concomitant increase in alveolar airspaces. CONCLUSIONS: DPI mediated glycolysis in lung and accordingly suppressed M2 programming, resulting in improved lung fibrosis.
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Fibrose Pulmonar , Camundongos , Animais , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , Pulmão/metabolismo , Macrófagos/metabolismo , Fibrose , Bleomicina/efeitos adversosRESUMO
Metastasis of clear cell renal cell carcinoma (ccRCC) is a leading cause of death. The purpose of this research was to investigate the key gene in ccRCC tumor metastasis. Three microarray datasets (GSE22541, GSE85258, and GSE105261), which included primary and metastatic ccRCC tissues, were obtained from the Gene Expression Omnibus (GEO) database. Expression profiling and clinical data of ccRCC were downloaded from The Cancer Genome Atlas (TCGA) dataset. A total of 20 overlapping differentially expressed genes (DEGs) were identified using the R limma package. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that the DEGs were mainly enriched in tumor metastasis-related pathways. Gene expression analysis and survival analysis in the GEPIA2 database further identified the key gene HSD11B2. qRT-PCR result manifested that HSD11B2 level was significantly down-regulated in ccRCC tissues compared with adjacent normal tissues. ROC analysis showed that HSD11B2 exhibited good diagnostic efficiency for metastatic and non-metastatic ccRCC. Univariate and multivariate Cox regression analysis showed that HSD11B2 expression was an independent prognostic factor. To establish a nomogram combining HSD11B2 expression and clinical factors, and a new method for predicting the survival probability of ccRCC patients. Gene Set Enrichment Analysis (GSEA) enrichment results showed that low expression of HSD11B2 was mainly enriched in tumor signaling pathways and immune-related pathways. Immune analysis revealed a significant correlation between HSD11B2 and tumor immune infiltrates in ccRCC. This study suggests that HSD11B2 can serve as a potential biomarker and therapeutic target for ccRCC metastasis.
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Carcinoma de Células Renais , Neoplasias Renais , Carcinoma de Células Renais/patologia , Biologia Computacional/métodos , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Renais/patologiaRESUMO
As the first line of defence in the lung, alveolar macrophage contributes to maintaining lung immune homoeostasis. Characterized by the heterogeneity and plasticity, macrophages polarize into two pro-inflammatory and anti-inflammatory phenotypes regarding the biological and pathological environment. In the past decade, numerous studies have revolutionized the relationship between cellular metabolism and macrophage functions. Mitochondria dysfunctions, which results in altered cellular metabolic profile, were observed in the alveolar macrophages during chronic lung diseases. In addition, alveolar macrophages adapt metabolic reprogramming to produce an immune response against the pathogens. Here, we outline the role of mitochondria in the development of macrophage phenotypes and functions and highlight the mitochondrial dysfunction in the setting of chronic lung diseases. Lastly, we emphasize the therapeutic relevance of targeting metabolic pathways in alveolar macrophages, which may shed light on developing novel strategies against chronic lung diseases.
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Pneumopatias , Macrófagos , Humanos , Macrófagos/metabolismo , Pneumopatias/metabolismo , Macrófagos Alveolares , Mitocôndrias/metabolismo , Pulmão/metabolismoRESUMO
Hepatitis B virus core protein (HBc) has become a hot spot in drug carrier protein research due to its natural particle self-assembly ability and ease of modification. The truncation of the C-terminal polyarginine domain (CTD, aa 151-183) of HBc does not affect the self-assembly of the particles. However, it does affect the internal and external charges of the particles, which may subsequently affect drug encapsulation. Thus, the truncated C-terminal polyarginine domain (CTD) of HBc and the inserted RGD peptide were selected to construct and express three HBc variants (RH) encapsulated with ICG (RH/ICG) with different C-terminal lengths to compare the stability and drug activity of their nanoformulations. RH160/ICG was found to have a great advantages in encapsulation efficiency and biological imaging. Compared with other HBc variants, RH160/ICG significantly improved encapsulation efficiency, up to 32.77%±1.23%. Cytotoxicity and hemolysis assays further demonstrated the good biocompatibility of RH160/ICG. Cell uptake and in vivo imaging experiments in mice showed that RH160/ICG could efficiently deliver ICG in tumor cells and tumor sites with good imaging effect. This research provides a new direction for further expanding the diagnosis and treatment application of ICG and development of HBc-based nanoparticle drug carrier platform.
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Hepatite B , Nanopartículas , Animais , Hepatite B/tratamento farmacológico , Antígenos do Núcleo do Vírus da Hepatite B , Verde de Indocianina/química , Camundongos , Nanopartículas/química , Proteínas do Core ViralRESUMO
Background: Interferon-α-1b, interleukin-2 combined with thalidomide (ITI) improved the outcome and prognosis of some acute myeloid leukemia (AML) patients, but the cases was insufficient. This study observed the efficacy and safety of this regimen in the treatment of numbers of AML patients in various disease states. Methods: Starting in January 2014, patients with AML (n=188) were treated with ITI regimen, including 60 refractory/relapses patients in group A, 40 patients in group B remained minimal residual disease-positive (MRD) or changed from negative to positive again after consolidation therapy, and 88 patients in group C with initial complete remission of AML received the ITI treatment after routine consolidation therapy. Bone marrow, fusion gene and MRD were detected to judge the curative effect and the adverse reactions were observed. The remission rate, MRD status and long-term survival of three groups were analyzed. An AML mouse model was constructed to observe the anti-leukemia effect of the three drugs in vivo. Results: Sixty patients with primary AML who were unable to receive chemotherapy, or with relapsed/refractory AML, showed a total response rate of 28.3% (17/60) after receiving the ITI regimen. Forty patients with morphologically complete remission and MRD-positive achieved a response rate of 77.5% (31/40); the MRD converted to negative in 19 patients and was mitigated in 12 patients. Among 88 patients with initial complete remission, 11 failed to maintain the negative MRD, and the relapse rate was 12.5%, which was significantly lower than that of the non-maintenance treatment group (54.3%). In the mouse model, interferon, interleukin-2, and thalidomide exerted an anti-leukemia effect, prolonged the survival time of the mice, and the anti-leukemia effect was further enhanced after administration of the combination ITI regimen. Conclusions: For suitable patients, hematopoietic stem cell transplantation is still strong recommended. The ITI regimen may be an effective option for patients with AML who cannot tolerate conventional chemotherapy, including those with relapsed/refractory disease, those with a complete remission status but are MRD-positive, or those who require maintenance treatment after consolidation therapy. However, a rigorous clinical randomized controlled trial and more in-depth mechanism exploration are still needed to verify this conclusion.
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Acute myelocytic leukemia (AML) is a frequent type of acute leukemia. The present study was performed to build a risk score system for the prognostic prediction of AML. AML RNA-sequencing data from samples from 111 children were downloaded from The Cancer Genome Atlas database. Using the DEseq and edgeR packages, the differentially expressed long non-coding RNAs (DE-lncRNAs) between bad and good prognosis groups were identified. A survival package was used to screen prognosis-associated lncRNAs and clinical factors. The optimal lncRNA combination was selected using the penalized package, and the risk-score system was built and evaluated. After the lncRNA-mRNA expression correlation network was constructed, the potential pathways involving the key lncRNAs were enriched using Gene Set Enrichment Analysis. Among the 61 DE-lncRNAs, 48 lncRNAs were significantly associated with prognosis. Relapse was an independent prognostic factor. The optimal 14-lncRNA risk score system was constructed. After 730 differentially expressed mRNAs were identified between the good and bad prognosis groups divided using a prognostic index, the lncRNA-mRNA expression correlation network was constructed. Enrichment analysis showed that semaphorin-3C [SEMA3C; regulated by probable leucine-tRNA ligase, mitochondrial (LARS2-AS1)] and secreted frizzled-related protein 5 [SFRP5; mediated by WASH complex subunit 5 (WASHC5)-antisense RNA 1 (AS1)] were involved in axon guidance and the Wnt signaling pathway, respectively. A 14-lncRNA (including paired box protein Pax8-AS1 and MYB AS1) risk-score system might be effective in predicting the prognosis of AML. Axon guidance (involving SEMA3C and LARS2-AS1) and the Wnt signaling pathway (involving SFRP5 and WASHC5-AS1) might be two important pathways affecting the prognosis of AML.
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Tumor therapeutic vaccines have faced a challenge for effective protection against malignant tumors by inducing tumor-specific CD8+ T cell responses. Here, we designed a DNA vaccine containing a tumor-specific antigen of Dickkopf-1 (DKK-1) and an immune checkpoint of programmed death ligand 1 (PD-L1) delivered by PLGA/PEI nanoparticle-mediated delivery system for multiple myeloma therapy. Murine subcutaneous tumor model established with human DKK1 (hDKK-1)-SP2/0 cells were intramuscularly immunized with PLGA/PEI-pPD-L1/pDDK-1 vaccine and equal amount of control 3 times at 10 day-intervals. Compared with PLGA/PEI-pDKK1 immunization group, PLGA/PEI-pPD-L1/pDKK-1 co-immunization enhanced the induction and mature of CD11c+ DCs and CD8+CD11c+ DCs, and promoted antigen-specific Th1 responses and cytotoxic T lymphocyte (CTL) responses. The reduced tumor volume and weight as well as increased tumor inhibition rate were observed in PLGA/PEI-pPD-L1/pDKK-1 vaccine co-immunization group, indicated that the vaccine could effectively inhibit the tumor growth of multiple myeloma. The anti-tumor activity of PLGA/PEI-pPD-L1/pDKK-1 vaccine was abrogated by CD8 cell depletion accompanied with the reduced percentages of CD8+CD11c+ DCs and CD8+ T cells in the spleen and TILs. These results indicated that the anti-tumor efficacy of PLGA/PEI-pPD-L1/pDKK-1 vaccine was required for CD8+CD11c+ DCs-mediated CD8+ T cell immunity responses. This vaccine strategy may represent a potential and promising approach for hematological malignancy treatment.
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Antígeno B7-H1/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Peptídeos e Proteínas de Sinalização Intercelular/imunologia , Mieloma Múltiplo/terapia , Vacinas de DNA/administração & dosagem , Animais , Antígeno B7-H1/genética , Linhagem Celular Tumoral , Citocinas/imunologia , Feminino , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Linfócitos do Interstício Tumoral/imunologia , Camundongos Endogâmicos BALB C , Mieloma Múltiplo/imunologia , Nanopartículas/administração & dosagem , Polietilenoimina/administração & dosagem , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/administração & dosagem , VacinaçãoRESUMO
BACKGROUND: In recent years, nanotechnology has attracted a plethora of attention due of its ability to effectively diagnose and treat various tumors. Virus-like particles (VLPs) have good biocompatibility, are safe and non-toxic, and have an internal hollow space, and as such they are often used as nano drug carriers. In recent years, it has become one of the hot spots in the field of biopharmaceutical engineering. METHODS: In this study, the tumor-targeting peptide RGD (Arg-Gly-Asp) was genetically inserted into the major immunodominant region (MIR) of the hepatitis B virus core protein (HBc). A series of characterization, including stability and optical properties, were evaluated. A visual diagnosis and analysis of the efficacy against tumor cells were conducted at the cell level and using a live animal model. RESULTS: This study demonstrated that the recombinant HBc-based VLPs could participate in self-assembly of monodispersed nanoparticles with well-defined morphology, and the near-infrared dye indocyanine green (ICG) could be packaged into the VLPs without any chemical modification. Moreover, the HBc-based VLPs could specifically target cancer cells via the interaction with overexpressed integrin αvß3. The treatment with ICG-loaded HBc-based VLPs showed significant inhibition of 4T1 breast cancer cell growth (84.87% tumor growth inhibition). The in vivo imaging experiments demonstrated that the ICG-loaded HBc-based VLPs generated excellent fluorescence in tumor sites in 4T1 breast cancer bearing mice. This provided crucial information on tumor mass location, boundaries, and shape. Moreover, compared to free ICG, the nanosystem showed significantly longer blood circulation time and superior accuracy in targeting the tumor. CONCLUSIONS: The ICG-loaded HBc-based VLPs prepared in this study were of good stability and biocompatibility. It showed strong tumor targeting specificity and tumor visualization. Thus, it is expected to provide a new experimental basis and theoretical support for the integration of VLPs in the clinical diagnosis and treatment of breast cancer.
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Endoplasmic reticulum (ER) stress is induced in chronic myelogenous leukemia (CML) cells. As an important sensor of ER stress, inositol-requiring protein-1α (IRE1α) promotes the survival of acute myeloid leukemia. NLRP1 inflammasome activation promotes metastatic melanoma growth and that IRE1α can increase NLRP1 inflammasome gene expression. This study aimed to investigate the role and molecular mechanism of IRE1α in CML cell growth. We found that overexpression of IRE1α or NLRP1 significantly promoted the proliferation and decreased the apoptosis of CML cells, whereas downregulation of these two genes showed the opposite effects. 4-phenylbutyric acid (4-PBA), an ER stress inhibitor, reduced the expression of IRE1α and NLRP1. IRE1α elevated NLRP1 expression via cAMP responsive element binding protein (CREB) phosphorylation. NLRP1 inflammasome was activated in CML cells and its activation partly reversed ER stress inhibitor-induced cell apoptosis. Furthermore, inhibition of IRE1α/NLRP1 pathway sensitized CML cells to imatinib-mediated apoptosis. Additionally, IRE1α expression was elevated and NLRP1 inflammasome was activated in primary cells from CML patients. Downregulation of IRE1α or NLRP1 suppressed the proliferation and elevated the apoptosis of primary CML cells. Collectively, this study demonstrated that the IRE1α/CREB/NLRP1 pathway contributes to the progression of CML and the development of imatinib resistance. Hence, targeting ER stress-related IRE1α expression or NLRP1 inflammasome activation may block CML development.
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Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Apoptose , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Estresse do Retículo Endoplasmático , Endorribonucleases/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Mesilato de Imatinib/farmacologia , Inflamassomos/metabolismo , Proteínas NLR , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacosRESUMO
Increasing evidence showed that mitochondria play an important role in the development of myelodysplastic syndromes (MDS). Mitochondrial dysfunctions caused by mitochondrial DNA mutations, especially mitochondrial tRNA mutations, were found to be associated with MDS in many studies. However, the link between a candidate mitochondrial tRNA mutation and MDS was not clear. In this study, we investigated the role of some mitochondrial tRNA mutations, and their deleterious roles were further discussed.
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Genes Mitocondriais , Estudos de Associação Genética , Predisposição Genética para Doença , Mutação , Síndromes Mielodisplásicas/genética , RNA de Transferência/genética , Alelos , Evolução Molecular , Genótipo , Humanos , Polimorfismo de Nucleotídeo ÚnicoRESUMO
OBJECTIVE: This study was performed to investigate the correlation between P15 methylation and hepatocellular carcinoma (HCC) and hepatocirrhosis using a meta-analysis of available case control studies. METHODS: Previous studies have primarily evaluated the incidence of P15 methylation in HCC and corresponding control groups, and compared the incidence of P15 methylation in liver cirrhosis and control groups. Data regarding publication information, study characteristics, and incidence of P15 methylation in both groups were collected from these studies and summarized. RESULTS: Ten studies that assessed P15 gene methylation in 824 HCC tumour tissues and five studies analyzing P15 methylation in 155 liver cirrhosis tissues met our inclusion criteria. Our meta-analysis revealed that the rate of P15 methylation was significantly higher in HCCs than in adjacent non-tumour tissues (OR 9.04, 95% CI 5.80-14.09, P < 0.00001). Moreover, P15 methylation was significantly higher in liver cirrhosis tissues than in control tissues (OR 7.82, 95% CI 3.58-17.07, P < 0.00001). CONCLUSIONS: we found that P15 methylation was associated with an increased risk of HCC and liver cirrhosis. P15 hypermethylation induced the inactivation of the P15 gene, which played an important role in hepatocarcinogenesis.