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1.
Nucleic Acids Res ; 52(D1): D1597-D1613, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37831097

RESUMO

The scope and function of RNA modifications in model plant systems have been extensively studied, resulting in the identification of an increasing number of novel RNA modifications in recent years. Researchers have gradually revealed that RNA modifications, especially N6-methyladenosine (m6A), which is one of the most abundant and commonly studied RNA modifications in plants, have important roles in physiological and pathological processes. These modifications alter the structure of RNA, which affects its molecular complementarity and binding to specific proteins, thereby resulting in various of physiological effects. The increasing interest in plant RNA modifications has necessitated research into RNA modifications and associated datasets. However, there is a lack of a convenient and integrated database with comprehensive annotations and intuitive visualization of plant RNA modifications. Here, we developed the Plant RNA Modification Database (PRMD; http://bioinformatics.sc.cn/PRMD and http://rnainformatics.org.cn/PRMD) to facilitate RNA modification research. This database contains information regarding 20 plant species and provides an intuitive interface for displaying information. Moreover, PRMD offers multiple tools, including RMlevelDiff, RMplantVar, RNAmodNet and Blast (for functional analyses), and mRNAbrowse, RNAlollipop, JBrowse and Integrative Genomics Viewer (for displaying data). Furthermore, PRMD is freely available, making it useful for the rapid development and promotion of research on plant RNA modifications.


Assuntos
Bases de Dados de Ácidos Nucleicos , Plantas , RNA de Plantas , Gerenciamento de Dados , Genômica , Plantas/genética , RNA de Plantas/genética
2.
Clin Genet ; 97(1): 25-38, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31432497

RESUMO

DNA mismatch repair (MMR) status was considered to be a potential prognostic factor for colorectal cancer (CRC) but with conflicting reports, and varied in terms of TNM stages. Its relationship with prognosis in stage II-III CRC had not yet been systematically established. Therefore, we retrieved eligible studies published through May 2019, and screened out 51 studies that reported survival data (overall survival [OS] and/or disease-free survival [DFS]) in 28 331 CRC patients at stage II-III, totally 16.4% of whom were characterized as deficient MMR (dMMR). Significant associations of dMMR status were observed with longer OS (Hazard Ratio [HR] = 0.74, 95% CI: 0.68-0.82; P < .001), as well as DFS (HR = 0.67, 95% CI: 0.59-0.75, P < .001). However, dMMR patients received no statistically significant benefit from fluoropyrimidine-based treatment for either OS (HR = 0.84, 95%CI: 0.60-1.17; P = .31) or DFS (HR = 0.83, 95%CI: 0.60-1.15; P = .27), compared with that in proficient MMR (pMMR) patients for both OS (HR = 0.55, 95% CI: 0.43-0.71; P < .001) and DFS (HR = 0.60, 95% CI: 0.50-0.73; P < .001). Our analysis indicate that dMMR CRC patients at stage II-III had higher OS and DFS than pMMR ones, and fluoropyrimidine-based chemotherapy could improve survival in pMMR patients rather than dMMR ones.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Reparo de Erro de Pareamento de DNA/genética , Prognóstico , Pirimidinas/uso terapêutico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Intervalo Livre de Doença , Humanos , Estadiamento de Neoplasias
3.
Nucleic Acids Res ; 44(8): 3629-42, 2016 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-26704979

RESUMO

Dicer participates in heterochromatin formation in fission yeast and plants. However, whether it has a similar role in mammals remains controversial. Here we showed that the human Dicer protein interacts with SIRT7, an NAD(+)-dependent H3K18Ac (acetylated lysine 18 of histone H3) deacetylase, and holds a proportion of SIRT7 in the cytoplasm. Dicer knockdown led to an increase of chromatin-associated SIRT7 and simultaneously a decrease of cytoplasmic SIRT7, while its overexpression induced SIRT7 reduction in the chromatin-associated fraction and increment in the cytoplasm. Furthermore, DNA damaging agents promoted Dicer expression, leading to decreased level of chromatin-associated SIRT7 and increased level of H3K18Ac, which can be alleviated by Dicer knockdown. Taken together with that H3K18Ac was exclusively associated with the chromatin, our findings suggest that Dicer induction by DNA damaging treatments prevents H3K18Ac deacetylation, probably by trapping more SIRT7 in the cytoplasm.


Assuntos
RNA Helicases DEAD-box/metabolismo , Dano ao DNA , Histonas/metabolismo , Ribonuclease III/metabolismo , Sirtuínas/metabolismo , Linhagem Celular , Cromatina/metabolismo , Cisplatino/toxicidade , RNA Helicases DEAD-box/antagonistas & inibidores , Doxorrubicina/toxicidade , Células HEK293 , Humanos , Radiação Ionizante , Ribonuclease III/antagonistas & inibidores
4.
Carcinogenesis ; 35(1): 155-63, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23917076

RESUMO

Hepatitis B surface antigen (HBsAg) seropositivity is an important risk factor for hepatocellular carcinoma (HCC), and HBsAg-transgenic mice have been reported to spontaneously develop HCC. The major histocompatibility complex class I-related molecules A and B (MICA and MICB) are NKG2D ligands that play important roles in tumor immune surveillance. In the present study, we found that HBsAg overexpression in HepG2 cells led to upregulation of 133 and downregulation of 9 microRNAs (miRNAs). Interestingly, several HBsAg-induced miRNAs repressed the expression of MICA and MICB via targeting their 3'-untranslated regions. In addition, the expression of MICA and MICB was significantly reduced upon HBsAg overexpression, which was partially restored by inhibiting the activities of HBsAg-induced miRNAs. Moreover, HBsAg-overexpressing HCC cells exhibited reduced sensitivity to natural killer cell-mediated cytolysis. Taken together, our data suggest that HBsAg supresses the expression of MICA and MICB via induction of cellular miRNAs, thereby preventing NKG2D-mediated elimination of HCC cells.


Assuntos
Carcinoma Hepatocelular/virologia , Antígenos de Superfície da Hepatite B/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Neoplasias Hepáticas/virologia , MicroRNAs/genética , Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica , Células Hep G2/virologia , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/patogenicidade , Vírus da Hepatite B/fisiologia , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/patologia , Neoplasias Hepáticas/genética
5.
Carcinogenesis ; 35(9): 2127-33, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24913918

RESUMO

Hepatitis B virus surface antigen (HBsAg) is an important risk factor for hepatocellular carcinoma (HCC) and is downregulated during hepatocarcinogenesis. MicroRNAs (miRNAs) are frequently deregulated in HCC tissues. However, whether the deregulation of certain miRNAs in HCC has an impact on HBsAg expression remains unclear. We found here that microRNA-581 (miR-581), which is deregulated during hepatocarcinogenesis, promoted HBsAg expression. Additionally, miR-581 targeted Dicer and endoplasmic reticulum degradation-enhancing alpha-mannosidase-like protein 1 (EDEM1) and repressed their expression. Although Dicer cannot process HBV transcripts, Dicer knockdown led to increased HBsAg secretion, most likely due to a reduction in the levels of Dicer-processed 7SL RNA fragments. Moreover, Dicer-processed 7SL RNA fragments partially inhibited the ability of miR-581 to stimulate HBsAg expression. Furthermore, we found that forced EDEM1 expression inhibited miR-581-mediated induction of HBsAg. Finally, transfection of miR-581 into HepG2.2.15 cells promoted cell proliferation and led to upregulation of genes involved in development, cell proliferation and protein secretion. Altogether, we conclude that miR-581 promotes HBsAg expression by targeting Dicer and EDEM1. Our findings suggest that downregulation of miR-581 during hepatocarcinogenesis may lead to a reduction in HBsAg expression and impede HCC development.


Assuntos
RNA Helicases DEAD-box/genética , Antígenos de Superfície da Hepatite B/metabolismo , Proteínas de Membrana/genética , MicroRNAs/genética , Ribonuclease III/genética , Regiões 3' não Traduzidas , Sítios de Ligação , RNA Helicases DEAD-box/metabolismo , Regulação Neoplásica da Expressão Gênica , Regulação Viral da Expressão Gênica , Células Hep G2 , Humanos , Proteínas de Membrana/metabolismo , Interferência de RNA , Ribonuclease III/metabolismo
6.
J Gastroenterol Hepatol ; 29(6): 1149-58, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24476011

RESUMO

BACKGROUND AND AIM: Controlled attenuation parameter (CAP) is a novel ultrasound-based elastography method for detection of steatosis severity. This meta-analysis aimed to assess the performance of CAP. METHODS: PubMed, the Cochrane Library, and the Web of Knowledge were searched to find studies, published in English, relating to accuracy evaluations of CAP for detecting stage 1 (S1), stage 2 (S2), or stage 3 (S3) hepatic steatosis which was diagnosed by liver biopsy. Sensitivities, specificities, and hierarchical summary receiver operating characteristic (HSROC) curves were used to examine CAP performance. The clinical utility of CAP was also evaluated. RESULTS: Nine studies, with 11 cohorts were analyzed. The summary sensitivities and specificities values were 0.78 (95% confidence interval [CI], 0.69-0.84) and 0.79 (95% CI, 0.68-0.86) for ≥ S1, 0.85 (95% CI, 0.74-0.92) and 0.79 (95% CI, 0.71-0.85) for ≥ S2, and 0.83 (95% CI, 0.76-0.89) and 0.79 (95% CI, 0.68-0.87) for ≥ S3. The HSROCs were 0.85 (95% CI, 0.81-88) for ≥ S1, 0.88 (95% CI, 0.85-0.91) for ≥ S2, and 0.87 (95% CI, 0.84-0.90) for ≥ S3. Following a "positive" measurement (over the threshold value) for ≥ S1, ≥ S2, and ≥ S3, the corresponding post-test probabilities for the presence of steatosis (pretest probability was 50%) were 78%, 80% and 80%, respectively; if the values were below these thresholds ("negative" results), the post-test probabilities were 22%, 16%, and 17%, respectively. CONCLUSIONS: CAP has good sensitivity and specificity for detecting hepatic steatosis; however, based on a meta-analysis, CAP was limited in their accuracy of steatosis, which precluded widespread use in clinical practice.


Assuntos
Bases de Dados Bibliográficas , Técnicas de Imagem por Elasticidade/métodos , Fígado Gorduroso/diagnóstico , Hepatopatias/diagnóstico , Ultrassonografia/métodos , Doença Crônica , Estudos de Coortes , Humanos , Curva ROC , Sensibilidade e Especificidade , Índice de Gravidade de Doença
7.
Ophthalmologica ; 232(2): 110-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24516061

RESUMO

PURPOSE: To evaluate the relationship between lumican polymorphisms and high myopia in Chinese populations. METHODS: An electronic search was conducted in Pubmed, Embase, Cochrane Library and the China Biological Medicine Database for articles published prior to September 30, 2012. A meta-analysis was performed to assess heterogeneity, combine results and determine publication bias. RESULTS: This meta-analysis, including 1,545 subjects from 5 studies, indicated that Chinese lumican rs3759223 C allele carriers had a decreased risk of high myopia in comparison to T allele carriers (odds ratio: 0.531; 95% confidence interval, CI: 0.304-0.925; p = 0.025). There was some heterogeneity between studies. A metaregression showed that the mean axial length of controls weakens the effect of rs3759223 on high myopia (slope: -0.914; 95% CI: -1.490 to 0.337; p = 0.002). Sensitivity analysis confirmed the reliability and stability of this meta-analysis. CONCLUSION: Chinese lumican rs3759223 C allele carriers may be at reduced risk of high myopia.


Assuntos
Povo Asiático/genética , Proteoglicanas de Sulfatos de Condroitina/genética , Sulfato de Queratano/genética , Miopia Degenerativa/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas/genética , Adulto , Estudos de Casos e Controles , China/epidemiologia , Feminino , Genótipo , Humanos , Lumicana , Masculino , Miopia Degenerativa/etnologia , Adulto Jovem
8.
Onkologie ; 36(10): 560-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24107909

RESUMO

BACKGROUND/AIMS: To accurately evaluate the impact of the C/T polymorphism in microRNA (miRNA)-196a2 on the colorectal cancer (CRC) risk, by meta-analysis. METHODS: An electronic search for articles was conducted in PubMed, EMBASE, ISI Web of Science, and the Cochrane Library. The pooled odds ratio (OR) and its 95% confidence interval (CI) were used to assess the association through meta-analysis. RESULTS: 5 studies were used for analysis. The results showed a significant association between the miRNA-196a2 C/T polymorphism and CRC risk in the genetic models (C vs. T: OR = 1.168, 95% CI = 1.106-1.282, p = 0.001; CC vs. TT: OR = 1.368, 95% CI = 1.132-1.654, p = 0.001; TC/CC vs. TT: OR = 1.206, 95% = CI 1.035-1.405, p = 0.016; CC vs. TC/TT: OR = 1.254, 95% CI = 1.077-1.461, p = 0.004), with the exception of the TC-versus-TT model (TC vs. TT: OR = 1.130, 95% CI = 0.961-1.329, p = 0.138). In a subgroup analysis based on ethnicity, we identified a significant overrepresentation of the polymorphism in individuals of Asian ethnicity. CONCLUSION: This meta-analysis indicates a significant association between the miRNA-196a2 polymorphism and CRC risk.


Assuntos
Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/genética , Marcadores Genéticos/genética , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único/genética , Feminino , Estudos de Associação Genética , Humanos , Masculino , Prevalência , Fatores de Risco
9.
Dis Markers ; 2022: 4254862, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36157209

RESUMO

Background: Various studies have produced contradictory results on the prognostic role of the CpG island methylator phenotype (CIMP) among colorectal cancer (CRC) patients. Although a meta-analysis published in 2014 reported a worse prognosis of CIMP among CIMP-high (CIMP-H) CRC patients, the sample sizes of the major included studies were small. In this study, we included the most recent studies with large sample sizes and performed an updated meta-analysis on the relationship between CIMP and CRC prognosis. Methods: A search of MEDLINE, Web of Science, and Cochrane for studies related to CIMP and CRC published until July 2021 was conducted based on the PICO (participant, intervention, control, outcome) framework. Data extraction and literature analyses were performed according to PRISMA standards. Results: In the present update, 36 eligible studies (20 recently published) reported survival data in 15315 CRC patients, 18.3% of whom were characterized as CIMP-H. Pooled analysis suggested that CIMP-H was associated with poorer overall survival (OS) (hazard ratio [HR] = 1.37, 95% CI: 1.26-1.48) and disease-free survival/progression-free survival/recurrence-free survival (DFS/PFS/RFS) (HR = 1.51, 95% CI: 1.19-1.91) among CRC patients. Subgroup analysis based on tumor stage and DNA mismatch repair (MMR) status showed that only patients with stages III-IV and proficient MMR (pMMR) tumors showed a significant association between CIMP-H and shorter OS, with HRs of 1.52 and 1.37, respectively. Three studies were pooled to explore the predictive value of CIMP on CRC patient DFS after receiving postoperative chemotherapy, and no significant correlation was found. Conclusion: CIMP-H is associated with a significantly poor prognosis in CRC patients, especially those with stage III-IV and pMMR tumors. However, the predictive value of CIMP needs to be confirmed by more prospective randomized studies.


Assuntos
Neoplasias Colorretais , Metilação de DNA , Neoplasias Colorretais/patologia , Ilhas de CpG , Humanos , Fenótipo , Prognóstico , Estudos Prospectivos
10.
Clin Lung Cancer ; 22(1): e70-e83, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33067126

RESUMO

BACKGROUND: Antiangiogenic agents combined with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are considered potentially effective biologically synergistic drug combinations for EGFR-mutant advanced non-small-cell lung cancer (NSCLC), although some controversy remains. The European Commission has approved the use of bevacizumab plus erlotinib as first-line treatment of EGFR-mutated NSCLC; however, it has not yet been approved by the U.S. Food and Drug Administration. Recently, several phase III, randomized controlled trials of combinations of antiangiogenic agents and EGFR-TKIs have been reported. These studies have not yet been included in any previous meta-analysis. MATERIALS AND METHODS: We performed a meta-analysis to compare antiangiogenic agents plus EGFR-TKIs versus EGFR-TKIs alone for treatment of EGFR-mutant NSCLC. The main outcomes were progression-free survival (PFS), overall survival (OS), the objective response rate (ORR), and adverse events (AEs). RESULTS: We identified 9 previous reports of 6 randomized controlled trials and 1 prospective cohort study, involving 1295 patients. Compared with EGFR-TKIs alone, antiangiogenic agents plus EGFR-TKIs resulted in a higher PFS (hazard ratio, 0.58; 95% confidence interval [CI], 0.50-0.67; P < .001). However, no significant differences in OS (hazard ratio, 0.79; 95% CI, 0.53-1.18; P = .26) and ORR (risk ratio, 1.03; 95% CI, 0.97-1.10; P = .30) were found between the 2 groups. An increased risk of serious AEs (risk ratio, 1.41; 95% CI, 1.11-1.79; P = .005) was found in the combination drug therapy group. CONCLUSIONS: Antiangiogenic agents plus EGFR-TKIs enhanced PFS for patients with EGFR-mutant NSCLC but with a greater risk of serious AEs. No significant benefits for OS and ORR were found between the 2 groups.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Quimioterapia Combinada , Receptores ErbB/antagonistas & inibidores , Humanos , Neoplasias Pulmonares/patologia , Prognóstico
11.
Front Genet ; 11: 1004, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33193587

RESUMO

Through genome-wide association studies (GWAS), multiple inherited predispositions to acute lymphoblastic leukemia (ALL) have been identified in children. Most recently, a novel susceptibility locus at ERG was localized, exhibiting Hispanic-specific manner. In this study, we conducted a replication study to in all-age Chinese patients (N = 451), not only validating the novel ERG locus, but also systematically determining the impact of age on association status of the top GWAS signals. We found that single nucleotide polymorphisms at ARID5B, IKZF1, CEBPE, PIP4K2A were only significantly associated with ALL susceptibility in childhood patients with no BCR-ABL fusion, while GATA3 signal exhibited its significance in adults no matter carrying BCR-ABL fusion or not. Moreover, the novel ERG SNP can be validated in pediatric patients without both BCR-ABL and ETV6-RUNX1 fusion. Our finding suggests the modifying effects of age on genetic predisposition to ALL, and highlights the impact of ERG SNP in Chinese patients.

12.
PLoS One ; 8(10): e76322, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24204613

RESUMO

OBJECTIVES: To perform a meta-analysis assessing the ability of shear wave elastography (SWE) to identify malignant breast masses. METHODS: PubMed, the Cochrane Library, and the ISI Web of Knowledge were searched for studies evaluating the accuracy of SWE for identifying malignant breast masses. The diagnostic accuracy of SWE was evaluated according to sensitivity, specificity, and hierarchical summary receiver operating characteristic (HSROC) curves. An analysis was also performed according to the SWE mode used: supersonic shear imaging (SSI) and the acoustic radiation force impulse (ARFI) technique. The clinical utility of SWE for identifying malignant breast masses was evaluated using analysis of Fagan plot. RESULTS: A total of 9 studies, including 1888 women and 2000 breast masses, were analyzed. Summary sensitivities and specificities were 0.91 (95% confidence interval [CI], 0.88-0.94) and 0.82 (95% CI, 0.75-0.87) by SSI and 0.89 (95% CI, 0.81-0.94) and 0.91 (95% CI, 0.84-0.95) by ARFI, respectively. The HSROCs for SSI and ARFI were 0.92 (95% CI, 0.90-0.94) and 0.96 (95% CI, 0.93-0.97), respectively. SSI and ARFI were both very informative, with probabilities of 83% and 91%, respectively, for correctly differentiating between benign and malignant breast masses following a "positive" measurement (over the threshold value) and probabilities of disease as low as 10% and 11%, respectively, following a "negative" measurement (below the threshold value) when the pre-test probability was 50%. CONCLUSIONS: SWE could be used as a good identification tool for the classification of breast masses.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Mama/patologia , Técnicas de Imagem por Elasticidade , Ultrassonografia Mamária , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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