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1.
EMBO J ; 37(20)2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30217955

RESUMO

Uncontrolled cell division is a hallmark of cancer. Deregulation of Wnt components has been linked to aberrant cell division by multiple mechanisms, including Wnt-mediated stabilisation of proteins signalling, which was notably observed in mitosis. Analysis of Wnt components revealed an unexpected role of B-cell CLL/lymphoma 9 (BCL9) in maintaining mitotic Wnt signalling to promote precise cell division and growth of cancer cell. Mitotic interactome analysis revealed a mechanistic role of BCL9 in inhibiting clathrin-mediated degradation of LRP6 signalosome components by interacting with clathrin and the components in Wnt destruction complex; this function was further controlled by CDK1-driven phosphorylation of BCL9 N-terminal, especially T172. Interestingly, T172 phosphorylation was correlated with cancer patient prognosis and enriched in tumours. Thus, our results revealed a novel role of BCL9 in controlling mitotic Wnt signalling to promote cell division and growth.


Assuntos
Proteína Quinase CDC2/metabolismo , Clatrina/metabolismo , Mitose , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Via de Sinalização Wnt , Células HCT116 , Células HeLa , Humanos , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Neoplasias/patologia , Fosforilação , Domínios Proteicos , Fatores de Transcrição
2.
FASEB J ; 33(8): 8759-8770, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31022357

RESUMO

Hepatocellular carcinoma (HCC) is a common and deadly cancer with limited treatment options. Through genome-wide growth depletion screens using clustered regularly interspaced short palindromic repeats and expression profiling of primary HCC tumors, we identified 13 clinically relevant target genes with therapeutic potential. Subsequent functional annotation analysis revealed significant enrichment of these 13 genes in the cell cycle, cell death, and survival pathways. Non-structural maintenance of chromosomes condensin I complex subunit G (NCAPG) was ranked the highest among the depletion screens and multiple HCC expression datasets. Transient inhibition of NCAPG using specific small interfering RNAs resulted in a significant reduction in cell growth, migration, and the down-regulation of mitochondrial gene expression in vitro. Small homologous RNA-mediated knockdown of NCAPG significantly impaired cell viability, caused aberrant mitotic division, fragmented the mitochondrial network, and increased cell death in vitro. HCC cells with a reduced expression of NCAPG formed significantly smaller xenograft tumors in vivo. Importantly, high NCAPG expression was significantly associated with poorer overall and disease-free survival in HCC patients. High NCAPG expression is a novel prognostic biomarker to predict HCC early recurrence after surgical resection. In conclusion, NCAPG is an essential gene for HCC tumor cell survival. It represents a promising novel target for treating HCC and a prognostic biomarker for clinical management of HCC.-Wang, Y., Gao, B., Tan, P. Y., Handoko, Y. A., Sekar, K., Deivasigamani, A., Seshachalam, V. P., OuYang, H.-Y., Shi, M., Xie, C., Goh, B. K. P., Ooi, L. L., Hui, K. M. Genome-wide CRISPR knockout screens identify NCAPG as an essential oncogene for hepatocellular carcinoma tumor growth.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Proteínas de Ciclo Celular/genética , Neoplasias Hepáticas/genética , Animais , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Feminino , Inativação Gênica , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Pessoa de Meia-Idade
3.
World J Surg ; 44(12): 4197-4206, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32860142

RESUMO

BACKGROUND: Liver resection (LR) is the main modality of treatment for hepatocellular carcinoma (HCC) and colorectal liver metastasis (CRLM). Post-hepatectomy liver failure (PHLF) remains the most dreaded complication. We aim to create a prognostic score for early risk stratification of patients undergoing LR. METHODOLOGY: Clinical and operative data of 472 patients between 2000 and 2016 with HCC or CRLM undergoing major hepatectomy were extracted and analysed from a prospectively maintained database. PHLF was defined using the 50-50 criteria. RESULTS: Liver cirrhosis and fatty liver were histologically confirmed in 35.6% and 53% of patients. 4.7% (n = 22) of patients had PHLF. A 90-day mortality was 5.1% (n = 24). Pre-operative albumin-bilirubin score (p = 0.0385), prothrombin time (p < 0.0001) and the natural logarithm of the ratio of post-operative day 1 to pre-operative serum bilirubin (SB) (ln(POD1Bil/pre-opBil); p < 0.0001) were significantly independent predictors of PHLF. The PHLF prognostic nomogram was developed using these factors with receiver operating curve showing area under curve of 0.88. Excellent sensitivity (94.7%) and specificity (95.7%) for the prediction of PHLF (50-50 criteria) were achieved at cut-offs of 9 and 11 points on this model. This score was also predictive of PHLF according to PeakBil > 7 and International Study Group for Liver Surgery criteria, intensive care unit admissions, length of stay, all complications, major complications, re-admissions and mortality (p < 0.05). CONCLUSIONS: The PHLF nomogram ( https://tinyurl.com/SGH-PHLF-Risk-Calculator ) can serve as a useful tool for early identification of patients at high risk of PHLF before the 'point of no return'. This allows enforcement of closer monitoring, timely intervention and mitigation of adverse outcomes.


Assuntos
Carcinoma Hepatocelular , Falência Hepática , Neoplasias Hepáticas , Carcinoma Hepatocelular/cirurgia , Hepatectomia/efeitos adversos , Humanos , Falência Hepática/diagnóstico , Falência Hepática/etiologia , Neoplasias Hepáticas/cirurgia , Nomogramas , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Prognóstico , Estudos Retrospectivos
4.
World J Surg Oncol ; 18(1): 237, 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32883292

RESUMO

BACKGROUND: Resection of colorectal liver metastases (CLM) has been established as the standard of care. This study aims to compare the change in clinicopathological characteristics of patients who underwent curative resection of CLM across two time periods-2000 to 2010 (P1) and 2011 to 2016 (P2) and evaluate the prognostic impact of these characteristics on survival outcomes. METHODS: Patients who undergo liver resection for CLM at Singapore General Hospital from January 2000 to December 2016 were identified from a prospectively maintained database. The primary end point was overall survival. RESULTS: There were 183/318 (57.5%) patients and 135/318 (42.5%) patients in P1 and P2, respectively. There was a lower proportion of patients who had nodal metastases from primary colorectal cancer and clinical risk score (CRS) less than 3 in P2 when compared to P1. There was no difference in survival between both time periods. Independent predictors of survival for the cohort were CEA levels ≥ 200 ng/ml, primary tumour grade and lymph nodal status. Independent predictors of poor survival in P1 were poorly differentiated colorectal cancer and nodal metastases while in P2, independent predictors of poor survival were multiple liver metastases and nodal metastases. CONCLUSION: Nodal metastases from primary colorectal cancer are an independent predictor of poor survival across time for resectable CLM. Although there is no difference in survival between the two time periods, patients with multiple liver metastases should be carefully considered prior to surgery as it is also an independent predictor of overall survival.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Estudos de Coortes , Neoplasias Colorretais/cirurgia , Hepatectomia , Humanos , Neoplasias Hepáticas/cirurgia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
5.
Int J Cancer ; 145(3): 662-670, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30653265

RESUMO

Early tumor recurrence after curative surgical resection poses a great challenge to the clinical management of hepatocellular carcinoma (HCC). We conducted whole genome expression microarrays on 64 primary HCC tumors with clinically defined recurrence status and cross-referenced with RNA-seq data from 18 HCC tumors in the Cancer Genome Atlas project. We identified a 77-gene signature, which is significantly associated with early recurrent (ER) HCC tumors. This ER-associated signature shows significant enrichment in genes involved in cell cycle pathway. We performed receiver operating characteristic (ROC) analysis to evaluate the prognostic biomarker potential of these 77 genes and Pearson correlation analysis to identify 11 close clusters. The one gene with the best area under the ROC curve in each of the 11 clusters was selected for validation using reverse-transcription quantitative PCR in an independent cohort of 24 HCC tumors. NUF2 was identified to be the minimal biomarker sufficient to discriminate ER tumors from LR tumors. NUF2 in combination with liver cirrhosis could significantly improve the detection of ER tumors with an AUROC of 0.82 and 0.85 in the test and validation cohort, respectively. In conclusion, NUF2 in combination with liver cirrhosis is a promising prognostic biomarker for early HCC recurrence.


Assuntos
Carcinoma Hepatocelular/metabolismo , Proteínas de Ciclo Celular/metabolismo , Neoplasias Hepáticas/metabolismo , Recidiva Local de Neoplasia/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Estudos de Coortes , Feminino , Humanos , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Valor Preditivo dos Testes , Taxa de Sobrevida , Transcriptoma
6.
Gut ; 66(2): 342-351, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-26669617

RESUMO

OBJECTIVE: The nature of the tumour-infiltrating leucocytes (TILs) is known to impact clinical outcome in carcinomas, including hepatocellular carcinoma (HCC). However, the role of tumour-infiltrating B cells (TIBs) remains controversial. Here, we investigate the impact of TIBs and their interaction with T cells on HCC patient prognosis. DESIGN: Tissue samples were obtained from 112 patients with HCC from Singapore, Hong Kong and Zurich and analysed using immunohistochemistry and immunofluorescence. RNA expression of CD19, CD8A, IFNG was analysed using quantitative PCR. The phenotype of freshly isolated TILs was analysed using flow cytometry. A mouse model depleted of mature B cells was used for functional study. RESULTS: Tumour-infiltrating T cells and B cells were observed in close contact with each other and their densities are correlated with superior survival in patients with HCC. Furthermore, the density of TIBs was correlated with an enhanced expression of granzyme B and IFN-γ, as well as with reduced tumour viability defined by low expression of Ki-67, and an enhanced expression of activated caspase-3 on tumour cells. CD27 and CD40 costimulatory molecules and TILs expressing activation marker CD38 in the tumour were also correlated with patient survival. Mice depleted of mature B cells and transplanted with murine hepatoma cells showed reduced tumour control and decreased local T cell activation, further indicating the important role of B cells. CONCLUSIONS: The close proximity of tumour-infiltrating T cells and B cells indicates a functional interaction between them that is linked to an enhanced local immune activation and contributes to better prognosis for patients with HCC.


Assuntos
Antígenos CD/análise , Linfócitos B/imunologia , Carcinoma Hepatocelular/imunologia , Neoplasias Hepáticas/imunologia , Linfócitos do Interstício Tumoral , Linfócitos T/imunologia , ADP-Ribosil Ciclase 1/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antígenos CD19/genética , Antígenos CD20/análise , Linfócitos B/química , Linfócitos B/patologia , Complexo CD3/análise , Antígenos CD40/análise , Antígenos CD8/análise , Antígenos CD8/genética , Carcinoma Hepatocelular/química , Carcinoma Hepatocelular/patologia , Caspase 3/análise , Progressão da Doença , Feminino , Expressão Gênica , Granzimas/análise , Humanos , Interferon gama/genética , Antígeno Ki-67/análise , Neoplasias Hepáticas/química , Neoplasias Hepáticas/patologia , Depleção Linfocítica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Fenótipo , Estudos Retrospectivos , Taxa de Sobrevida , Linfócitos T/química , Linfócitos T/patologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/análise , Adulto Jovem
7.
Gut ; 65(9): 1522-34, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26941395

RESUMO

OBJECTIVES: Hepatocellular carcinoma (HCC) is the second leading cause of cancer mortality worldwide. Alterations in microtubule-associated proteins (MAPs) have been observed in HCC. However, the mechanisms underlying these alterations remain poorly understood. Our aim was to study the roles of the MAP protein regulator of cytokinesis 1 (PRC1) in hepatocarcinogenesis and early HCC recurrence. DESIGN: PRC1 expression in HCC samples was evaluated by microarray, immunoblotting and immunohistochemistry analysis. Molecular and cellular techniques including siRNA-mediated and lentiviral vector-mediated knockdown were used to elucidate the functions and mechanisms of PRC1. RESULTS: PRC1 expression was associated with early HCC recurrence and poor patient outcome. In HCC, PRC1 exerted an oncogenic effect by promoting cancer proliferation, stemness, metastasis and tumourigenesis. We further demonstrated that the expression and distribution of PRC1 is dynamically regulated by Wnt3a signalling. PRC1 knockdown impaired transcription factor (TCF) transcriptional activity, decreased Wnt target expression and reduced nuclear ß-catenin levels. Mechanistically, PRC1 interacts with the ß-catenin destruction complex, regulates Wnt3a-induced membrane sequestration of this destruction complex, inhibits adenomatous polyposis coli (APC) stability and promotes ß-catenin release from the APC complex. In vivo, high PRC1 expression correlated with nuclear ß-catenin and Wnt target expression. PRC1 acted as a master regulator of a set of 48 previously identified Wnt-regulated recurrence-associated genes (WRRAGs) in HCC. Thus, PRC1 controlled the expression and function of WRRAGs such as FANCI, SPC25, KIF11 and KIF23 via Wnt signalling. CONCLUSIONS: We identified PRC1 as a novel Wnt target that functions in a positive feedback loop that reinforces Wnt signalling to promote early HCC recurrence.


Assuntos
Carcinoma Hepatocelular , Proteínas de Ciclo Celular/genética , Neoplasias Hepáticas , Recidiva Local de Neoplasia/genética , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas Experimentais , Camundongos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/genética , beta Catenina/metabolismo
8.
Gut ; 65(12): 1960-1972, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-26338826

RESUMO

BACKGROUND: GI stromal tumours (GISTs) are clinically heterogenous exhibiting varying degrees of disease aggressiveness in individual patients. OBJECTIVES: We sought to identify genetic alterations associated with high-risk GIST, explore their molecular consequences, and test their utility as prognostic markers. DESIGNS: Exome sequencing of 18 GISTs was performed (9 patients with high-risk/metastatic and 5 patients with low/intermediate-risk), corresponding to 11 primary and 7 metastatic tumours. Candidate alterations were validated by prevalence screening in an independent patient cohort (n=120). Functional consequences of SETD2 mutations were investigated in primary tissues and cell lines. Transcriptomic profiles for 8 GISTs (4 SETD2 mutated, 4 SETD2 wild type) and DNA methylation profiles for 22 GISTs (10 SETD2 mutated, 12 SETD2 wild type) were analysed. Statistical associations between molecular, clinicopathological factors, and relapse-free survival were determined. RESULTS: High-risk GISTs harboured increased numbers of somatic mutations compared with low-risk GISTs (25.2 mutations/high-risk cases vs 6.8 mutations/low-risk cases; two sample t test p=3.1×10-5). Somatic alterations in the SETD2 histone modifier gene occurred in 3 out of 9 high-risk/metastatic cases but no low/intermediate-risk cases. Prevalence screening identified additional SETD2 mutations in 7 out of 80 high-risk/metastatic cases but no low/intermediate-risk cases (n=29). Combined, the frequency of SETD2 mutations was 11.2% (10/89) and 0% (0/34) in high-risk and low-risk GISTs respectively. SETD2 mutant GISTs exhibited decreased H3K36me3 expression while SETD2 silencing promoted DNA damage in GIST-T1 cells. In gastric GISTs, SETD2 mutations were associated with overexpression of HOXC cluster genes and a DNA methylation signature of hypomethylated heterochromatin. Gastric GISTs with SETD2 mutations, or GISTs with hypomethylated heterochromatin, showed significantly shorter relapse-free survival on univariate analysis (log rank p=4.1×10-5). CONCLUSIONS: Our data suggest that SETD2 is a novel GIST tumour suppressor gene associated with disease progression. Assessing SETD2 genetic status and SETD2-associated epigenomic phenotypes may guide risk stratification and provide insights into mechanisms of GIST clinical aggressiveness.


Assuntos
Biomarcadores Tumorais/genética , Tumores do Estroma Gastrointestinal/genética , Histona-Lisina N-Metiltransferase/genética , Mutação de Sentido Incorreto , Estudos de Casos e Controles , Códon sem Sentido/genética , Metilação de DNA/genética , Exoma/genética , Tumores do Estroma Gastrointestinal/epidemiologia , Tumores do Estroma Gastrointestinal/patologia , Histonas/genética , Humanos , Mutação de Sentido Incorreto/genética , Invasividade Neoplásica , Fenótipo , Prevalência , Prognóstico , Índice de Gravidade de Doença , Singapura/epidemiologia
9.
Gastric Cancer ; 19(2): 453-465, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26205786

RESUMO

BACKGROUND: Gastric cancer, a leading cause of cancer death worldwide, has been little studied compared with other cancers that impose similar health burdens. Our goal is to assess genomic copy-number loss and the possible functional consequences and therapeutic implications thereof across a large series of gastric adenocarcinomas. METHODS: We used high-density single-nucleotide polymorphism microarrays to determine patterns of copy-number loss and allelic imbalance in 74 gastric adenocarcinomas. We investigated whether suppressor of tumorigenesis and/or proliferation (STOP) genes are associated with genomic copy-number loss. We also analyzed the extent to which copy-number loss affects Copy-number alterations Yielding Cancer Liabilities Owing to Partial losS (CYCLOPS) genes-genes that may be attractive targets for therapeutic inhibition when partially deleted. RESULTS: The proportion of the genome subject to copy-number loss varies considerably from tumor to tumor, with a median of 5.5 %, and a mean of 12 % (range 0-58.5 %). On average, 91 STOP genes were subject to copy-number loss per tumor (median 35, range 0-452), and STOP genes tended to have lower copy-number compared with the rest of the genes. Furthermore, on average, 1.6 CYCLOPS genes per tumor were both subject to copy-number loss and downregulated, and 51.4 % of the tumors had at least one such gene. CONCLUSIONS: The enrichment of STOP genes in regions of copy-number loss indicates that their deletion may contribute to gastric carcinogenesis. Furthermore, the presence of several deleted and downregulated CYCLOPS genes in some tumors suggests potential therapeutic targets in these tumors.


Assuntos
Adenocarcinoma/genética , Dosagem de Genes , Regulação Neoplásica da Expressão Gênica , Neoplasias Gástricas/genética , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Proliferação de Células , Genes Supressores de Tumor , Humanos , Perda de Heterozigosidade , Polimorfismo de Nucleotídeo Único , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia
10.
J Hepatol ; 63(4): 863-73, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25980764

RESUMO

BACKGROUND & AIMS: Patients with advanced hepatocellular carcinoma (HCC) continue to have a dismal prognosis. Early recurrence, metastases and angiogenesis are the major obstacles to improve the outcome of HCC. Epithelial-mesenchymal transition (EMT) is a key contributor to cancer metastasis and recurrence, which are the major obstacles to improve prognosis of HCC. METHODS: Combining gene expression profiles of HCC samples with or without early recurrence and established cell lines with epithelial or mesenchymal phenotype, EDIL3 was identified as a novel regulator of EMT. The expression of EDIL3 was evaluated by quantitative PCR, Western blotting or immunohistochemistry. The effects of EDIL3 on the angiogenesis and metastasis of HCC cells were examined by wound healing, Matrigel invasion and tube formation assay in vitro and orthotopic xenograft mouse model of HCC in vivo. The signaling pathways of EDIL3 mediated were investigated through microarray and Western blotting analysis. RESULTS: EDIL3 was identified as a novel regulator of EMT, which contributes to angiogenesis, metastasis and recurrence of HCC. EDIL3 induces EMT and promotes HCC migration, invasion and angiogenesis in vitro. Mechanistically, overexpression of EDIL3, which was regulated by the downregulation of miR-137 in HCC, triggered the activation of ERK and TGF-ß signaling through interactions with αvß3 integrin. Blocking ERK and TGF-ß signaling overcomes EDIL3 induced angiogenesis and invasion. Using the orthotopic xenograft mouse model of HCC, we demonstrated that EDIL3 enhanced the tumorigenic, metastatic and angiogenesis potential of HCC in vivo. CONCLUSIONS: EDIL3-mediated activation of TGF-ß and ERK signaling could provide therapeutic implications for HCC.


Assuntos
Carcinoma Hepatocelular/genética , Proteínas de Transporte/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas Experimentais/genética , Recidiva Local de Neoplasia/genética , RNA Neoplásico/genética , Animais , Western Blotting , Proteínas de Ligação ao Cálcio , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Proteínas de Transporte/biossíntese , Moléculas de Adesão Celular , Linhagem Celular Tumoral , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intercelular , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Reação em Cadeia da Polimerase , Fatores de Tempo
11.
J Hepatol ; 62(6): 1287-95, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25617497

RESUMO

BACKGROUND & AIMS: Early recurrence is the major obstacle for improving the outcome of patients with hepatocellular carcinoma (HCC). Therefore, identifying key molecules contributing to early HCC recurrence can enable the development of novel therapeutic strategies for the clinical management of HCC. Epithelial cell transforming sequence 2 (ECT2) has been implicated in human cancers, but its function in HCC is largely unknown. METHODS: ECT2 expression was studied by microarrays, immunoblotting and immunohistochemistry in human HCC samples. siRNA- and lentiviral vector-mediated knockdown were employed to decipher the molecular functions of ECT2. RESULTS: The upregulation of ECT2 is significantly associated with early recurrent HCC disease and poor survival. Knockdown of ECT2 markedly suppressed Rho GTPases activities, enhanced apoptosis, attenuated oncogenicity and reduced the metastatic ability of HCC cells. Moreover, knockdown of ECT2 or Rho also suppressed ERK activation, while the silencing of Rho or ERK led to a marked reduction in cell migration. Stable knockdown of ECT2 in vivo resulted in significant retardation of tumour growth and the suppression of ERK activation. High expression of ECT2 correlates with high ERK phosphorylation and poor survival of HCC patients. Furthermore, ECT2 enhances the expression and stability of RACGAP1, accelerating ECT2-mediated Rho activation to promote metastasis. CONCLUSIONS: ECT2 is closely associated with the activation of the Rho/ERK signalling axis to promote early HCC recurrence. In addition, ECT2 can crosstalk with RACGAP1 to catalyse the GTP exchange involved in Rho signalling to further regulate tumour initiation and metastasis.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Sistema de Sinalização das MAP Quinases , Proteínas Proto-Oncogênicas/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Animais , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/secundário , Linhagem Celular Tumoral , Movimento Celular , Feminino , Proteínas Ativadoras de GTPase/metabolismo , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/etiologia , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , Fatores de Tempo , Regulação para Cima
12.
Hepatology ; 58(2): 629-41, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23471579

RESUMO

UNLABELLED: Tumor recurrence and metastases are the major obstacles to improving the prognosis of patients with hepatocellular carcinoma (HCC). To identify novel risk factors associated with HCC recurrence and metastases, we have established a panel of recurrence-associated microRNAs (miRNAs) by comparing miRNA expression in recurrent and nonrecurrent human HCC tissue samples using microarrays (recurrence is defined as recurrent disease occurring within a 2-year time point of the original treatment). Among the panel, expression of the miR-216a/217 cluster was consistently and significantly up-regulated in HCC tissue samples and cell lines associated with early tumor recurrence, poor disease-free survival, and an epithelial-mesenchymal transition (EMT) phenotype. Stable overexpression of miR-216a/217-induced EMT increased the stem-like cell population, migration, and metastatic ability of epithelial HCC cells. Phosphatase and tensin homolog (PTEN) and mothers against decapentaplegic homolog 7 (SMAD7) were subsequently identified as two functional targets of miR-216a/217, and both PTEN and SMAD7 were down-regulated in HCC. Ectopic expression of PTEN or SMAD7 partially rescued miR-216a/217-mediated EMT, cell migration, and stem-like properties of HCC cells. Previously, SMAD7 was shown to be a transforming growth factor beta (TGF-ß) type 1 receptor antagonist. Here, we further demonstrated that overexpression of miR-216a/217 acted as a positive feedback regulator for the TGF-ß pathway and the canonical pathway involved in the activation of phosphoinositide 3-kinase/protein kinase K (PI3K/Akt) signaling in HCC cells. Additionally, activation of the TGF-ß- and PI3K/Akt-signaling pathways in HCC cells resulted in an acquired resistance to sorafenib, whereas blocking activation of the TGF-ß pathway overcame miR-216a/217-induced sorafenib resistance and prevented tumor metastases in HCC. CONCLUSION: Overexpression of miR-216a/217 activates the PI3K/Akt and TGF-ß pathways by targeting PTEN and SMAD7, contributing to hepatocarcinogenesis and tumor recurrence in HCC.


Assuntos
Carcinoma Hepatocelular/fisiopatologia , Resistencia a Medicamentos Antineoplásicos/fisiologia , Transição Epitelial-Mesenquimal/fisiologia , Neoplasias Hepáticas/fisiopatologia , MicroRNAs/fisiologia , Recidiva Local de Neoplasia/fisiopatologia , PTEN Fosfo-Hidrolase/fisiologia , Proteína Smad7/fisiologia , Animais , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Técnicas In Vitro , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Niacinamida/análogos & derivados , Niacinamida/farmacologia , Compostos de Fenilureia/farmacologia , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Transdução de Sinais/fisiologia , Sorafenibe , Fator de Crescimento Transformador beta/fisiologia , Regulação para Cima/fisiologia
13.
J Hepatol ; 59(5): 999-1006, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23867315

RESUMO

BACKGROUND & AIMS: Although attenuated measles virus (MV) has demonstrated potent oncolytic activities towards human cancers, it has not yet been widely adopted into clinical practice. One of the major hurdles is the presence of pre-existing anti-MV immunity in the recipients. In this study, we have evaluated the combination of the potent oncolytic activity of the attenuated MV with the unique immunoprivileged and tumor-tropic biological properties of human bone marrow-derived mesenchymal stem cells (BM-hMSCs) to combat human hepatocellular carcinoma (HCC), orthotopically implanted in SCID mice, passively immunized with human neutralizing antibodies against MV as a preclinical model. METHODS: SCID mice were orthotopically implanted with patient-derived HCC tissues and established HCC cell lines. SCID mice were passively immunized with human neutralizing anti-measles antibodies. Bioluminescence and fluorescence imaging were employed to monitor the ability of systemically delivered MV-infected BM-hMSCs to infiltrate the implanted tumors and their effects on tumor growth. RESULTS: Systemically delivered MV-infected BM-hMSCs homed to the HCC tumors implanted orthotopically in the liver and it was evidenced that BM-hMSCs could transfer MV infectivity to HCC via heterofusion. Furthermore, therapy with MV-infected BM-hMSCs resulted in significant inhibition of tumor growth in both measles antibody-naïve and passively-immunized SCID mice. By contrast, when cell-free MV viruses were delivered systemically, antitumor activity was evident only in measles antibody-naïve SCID mice. CONCLUSIONS: MV-infected BM-hMSCs cell delivery system provides a feasible strategy to elude the presence of immunity against MV in most of the potential cancer patients to be treated with the oncolytic MV viruses.


Assuntos
Imunização Passiva , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/prevenção & controle , Vírus do Sarampo/patogenicidade , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/virologia , Vírus Oncolíticos/patogenicidade , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/uso terapêutico , Células da Medula Óssea/patologia , Células da Medula Óssea/virologia , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/prevenção & controle , Carcinoma Hepatocelular/virologia , Linhagem Celular Tumoral , Proliferação de Células , Técnicas de Cocultura , Modelos Animais de Doenças , Xenoenxertos , Humanos , Imunização Passiva/métodos , Neoplasias Hepáticas/virologia , Vírus do Sarampo/imunologia , Células-Tronco Mesenquimais/patologia , Camundongos , Camundongos SCID , Vírus Oncolíticos/imunologia
14.
Gut ; 61(3): 427-38, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21930732

RESUMO

OBJECTIVE: Hepatocellular carcinoma (HCC) is a heterogeneous disease with poor prognosis and limited methods for predicting patient survival. The nature of the immune cells that infiltrate tumours is known to impact clinical outcome. However, the molecular events that regulate this infiltration require further understanding. Here the ability of immune genes expressed in the tumour microenvironment to predict disease progression was investigated. METHODS: Using quantitative PCR, the expression of 14 immune genes in resected tumour tissues from 57 Singaporean patients was analysed. The nearest-template prediction method was used to derive and test a prognostic signature from this training cohort. The signature was then validated in an independent cohort of 98 patients from Hong Kong and Zurich. Intratumoural components expressing these critical immune genes were identified by in situ labelling. Regulation of these genes was analysed in vitro using the HCC cell line SNU-182. RESULTS: The identified 14 immune-gene signature predicts patient survival in both the training cohort (p=0.0004 and HR=5.2) and the validation cohort (p=0.0051 and HR=2.5) irrespective of patient ethnicity and disease aetiology. Importantly, it predicts the survival of patients with early disease (stages I and II), for whom classical clinical parameters provide limited information. The lack of predictive power in late disease stages III and IV emphasises that a protective immune microenvironment has to be established early in order to impact disease progression significantly. This signature includes the chemokine genes CXCL10, CCL5 and CCL2, whose expression correlates with markers of T helper 1 (Th1), CD8(+) T and natural killer (NK) cells. Inflammatory cytokines (tumour necrosis factor α, interferon γ) and Toll-like receptor 3 ligands stimulate intratumoural production of these chemokines which drive tumour infiltration by T and NK cells, leading to enhanced cancer cell death. CONCLUSION: A 14 immune-gene signature, which identifies molecular cues driving tumour infiltration by lymphocytes, accurately predicts survival of patients with HCC especially in early disease.


Assuntos
Carcinoma Hepatocelular/imunologia , Quimiocinas/imunologia , Neoplasias Hepáticas/imunologia , Linfócitos do Interstício Tumoral/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos T CD8-Positivos/imunologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Quimiocina CCL2/metabolismo , Quimiocina CCL5/metabolismo , Quimiocina CXCL10/metabolismo , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Células Matadoras Naturais/imunologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Células Th1/imunologia , Receptor 3 Toll-Like/imunologia , Adulto Jovem
15.
Support Care Cancer ; 20(5): 1049-56, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21556720

RESUMO

PURPOSE: Previous studies have demonstrated high prevalence of unmet psychosocial needs among cancer patients, but few were conducted among Asians. In this cross-sectional study, we investigated the prevalence of and factors associated with unmet psychosocial needs among cancer patients undergoing ambulatory care at a cancer centre in Singapore. METHOD: We conducted a cross-sectional study among 535 breast, gynaecological and colorectal cancer patients (response rate, 76%) using a modified version of the Cancer Survivors' Unmet Needs measure questionnaire, to assess the prevalence of patients' needs for disease information and social support, physical needs, financial needs and psychological needs, and the extent to which needs were met. Logistic regression analysis was used to identify demographic or disease characteristics associated with unmet needs. RESULTS: Seventy-five per cent of patients reported having any unmet needs, with disease information needs being most prevalent (61.5%) followed by financial (40.2%), social support (39.7%), psychological (27.3%) and physical (26.1%) needs. Factors independently associated with having high level of unmet needs were age below 60 years, ethnic minority, advanced disease and recent diagnosis. CONCLUSION: The prevalence of unmet psychosocial needs among cancer patients in ambulatory care is generally high. Young patients with disease recently diagnosed at advanced stage will benefit from additional support.


Assuntos
Neoplasias da Mama/psicologia , Neoplasias Colorretais/psicologia , Neoplasias dos Genitais Femininos/psicologia , Apoio Social , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Assistência Ambulatorial/métodos , Povo Asiático , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Estudos Transversais , Feminino , Neoplasias dos Genitais Femininos/patologia , Neoplasias dos Genitais Femininos/terapia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Avaliação das Necessidades , Educação de Pacientes como Assunto , Prevalência , Singapura , Inquéritos e Questionários
16.
Heliyon ; 8(1): e08731, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35036591

RESUMO

The COVID-19 pandemic has affected surgical education and training significantly. The main impact to surgical residency training is the reduction in number of patients (in caseload and case mix) and the conversion of face-to-face meetings into virtual ones for CME and clinical governance-related events. Assessment of surgical residents by examination (namely the Joint Specialty Fellowship Examination with the College of Surgeons of Hong Kong and the Royal College of Surgeons of Edinburgh) was cancelled at the peak of the pandemic, with resumption after acceptable COVID compatible adjustment was made to the format. The migration of CME events into a web-based one has resulted in greater connectivity with more audience. The potential and challenges of virtual format in surgical education include strategy and resources for sustainability; choice of optimal model for effective learning and surgical skills acquisition. In a post-COVID world, the model of blended learning is likely to remain.

17.
J Hepatocell Carcinoma ; 9: 839-851, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35999856

RESUMO

Objective: We aimed to prognosticate survival after surgical resection of HCC stratified by stage with amalgamation of the modified Barcelona Clinic Liver Cancer (BCLC) staging system and location of tumour. Methods: This single-institutional retrospective cohort study included patients with HCC who underwent surgical resection between 1st January 2000 to 30th June 2016. Participants were divided into 6 different subgroups: A-u) Within MC with Unilobar lesions; A-b) Within MC + Bilobar lesions; B1-u) Out of MC + within Up-To-7 + Unilobar lesions; B1-b) Out of MC + within Up-to-7 + Bilobar lesions; B2-u) Out of MC + Out of Up-To-7 + Unilobar lesions; B2-b) Out of MC + Out of Up-To-7 + Bilobar lesions. A separate survival analysis was conducted for solitary HCC lesions according to three subgroups: A-S (Within MC); B1-S (Out of MC + within Up-To-7); B2-S (Out of MC + out of Up-To-7). Results: A total of 794 of 1043 patients with surgical resection for HCC were analysed. Groups A-u (64.6%), A-b (58.4%) and B1-u (56.2%) had 5-year cumulative overall survival (OS) rates above 50% after surgical resection and median OS exceeding 60 months (P = 0.0001). The 5-year cumulative recurrence-free survival rates (RFS) were 40.4% (group A-u), 38.2% (group A-b), 36.3% (group B1-u), 24.6% (group B2-u), and 7.3% (group B2-b)(P=0.0001). For solitary lesions, the 5-year OS for the subgroups were A-S (65.1%), B1-S (56.0%) and B2-S (47.1%) (P = 0.0003). Compared to A-S, there was also a significant trend towards relatively poorer OS as the lesion sizes increased in B1-S (HR 1.46, 95% CI 1.03-2.08) and B2-S (HR 1.65, 95% CI 1.25-2.18). Conclusion: We adopted a novel approach combining the modified BCLC B sub-classification and dispersion of tumour to show that surgical resection in intermediate stage HCC can be robustly prognosticated. We found that size prognosticates resection outcomes in solitary tumours.

18.
Cancer Res Treat ; 53(4): 944-961, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33421974

RESUMO

PURPOSE: NUF2 has been implicated in multiple cancers recently, suggesting NUF2 may play a role in the common tumorigenesis process. In this study, we aim to perform comprehensive meta-analysis of NUF2 expression in the cancer types included in the Cancer Genome Atlas (TCGA). MATERIALS AND METHODS: RNA-sequencing data in 31 cancer types in the TCGA data and 11 independent datasets were used to examine NUF2 expression. Silencing NUF2 using targeting shRNAs in hepatocellular carcinoma (HCC) cell lines was used to evaluate NUF2's role in HCC in vitro and in vivo. RESULTS: NUF2 up-regulation is significantly observed in 23 out of the 31 cancer types in the TCGA datasets and validated in 13 major cancer types using 11 independent datasets. NUF2 overexpression was clinically important as high NUF2 was significantly associated with tumor stages in eight different cancers. High NUF2 was also associated with significantly poorer patient overall survival and disease-free survival in eight and six cancers, respectively. We proceeded to validate NUF2 overexpression and its negative association with overall survival at the protein level in an independent cohort of 40 HCC patients. Compared to the non-targeting controls, NUF2 knockdown cells showed significantly reduced ability to grow, migrate into a scratch wound and invade the 8 µm porous membrane in vitro. Moreover, NUF2 knockdown cells also formed significantly smaller tumors than control cells in mouse xenograft assays in vivo. CONCLUSION: NUF2 up-regulation is a common feature of many cancers. The prognostic potential and functional impact of NUF2 up-regulation warrant further studies.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteínas de Ciclo Celular/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias/mortalidade , Animais , Apoptose , Biomarcadores Tumorais/genética , Proteínas de Ciclo Celular/genética , Proliferação de Células , Feminino , Humanos , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Cancer Rep (Hoboken) ; 4(5): e1393, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33939335

RESUMO

BACKGROUND: Pancreatic adenocarcinoma (PDAC) is highly lethal. Surgery offers the only chance of cure, but 5-year overall survival (OS) after surgical resection and adjuvant therapy remains dismal. Adjuvant trials were mostly conducted in the West enrolling fit patients. Applicability to a general population, especially Asia has not been described adequately. AIM: We aimed to evaluate the clinical outcomes, prognostic factors of survival, pattern, and timing of recurrence after curative resection in an Asian institution. METHODS AND RESULTS: The clinicopathologic and survival outcomes of 165 PDAC patients who underwent curative resection between 1998 and 2013 were reviewed retrospectively. Median age at surgery was 62.0 years. 55.2% were male, and 73.3% had tumors involving the head of pancreas. The median OS of the entire cohort was 19.7 months. Median OS of patients who received adjuvant chemotherapy was 23.8 months. Negative predictors of survival include lymph node ratio (LNR) of >0.3 (HR = 3.36, P = .001), tumor site involving the body or tail of pancreas (HR = 1.59, P = .046), presence of perineural invasion (PNI) (HR = 2.36, P = .018) and poorly differentiated/undifferentiated tumor grade (HR = 1.86, P = .058). The median time to recurrence was 8.87 months, with 66.1% and 81.2% of patients developing recurrence at 12 months and 24 months respectively. The most common site of recurrence was the liver. CONCLUSION: The survival of Asian patients with resected PDAC who received adjuvant chemotherapy is comparable to reported randomized trials. Clinical characteristics seem similar to Western patients. Hence, geographical locations may not be a necessary stratification factor in RCTs. Conversely, lymph node ratio and status of PNI ought to be incorporated.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Ductal Pancreático/mortalidade , Quimioterapia Adjuvante/mortalidade , Recidiva Local de Neoplasia/mortalidade , Pancreatectomia/mortalidade , Neoplasias Pancreáticas/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/terapia , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/terapia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , Prognóstico , Estudos Retrospectivos , Singapura , Taxa de Sobrevida
20.
Lancet Oncol ; 10(11): 1111-8, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19880065

RESUMO

Asia has a disproportionately large share of the world's hepatocellular carcinoma (HCC), mainly because of the endemic status of chronic hepatitis B and C viruses, which leads to liver cirrhosis and an increased risk of HCC. This etiological factor presents important opportunities for prevention, early detection, diagnosis, and treatment of HCC. This consensus statement reviews the available medical evidence for management of HCC in Asia, and gives treatment recommendations that are adapted to resource availability in this diverse region with disparate health-care delivery systems.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/terapia , Países em Desenvolvimento , Procedimentos Cirúrgicos do Sistema Digestório , Neoplasias Hepáticas/terapia , Oncologia , Serviços Preventivos de Saúde , Antineoplásicos/economia , Antivirais/uso terapêutico , Ásia/epidemiologia , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/economia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/prevenção & controle , Carcinoma Hepatocelular/virologia , Ablação por Cateter , Quimioembolização Terapêutica , Quimioterapia Adjuvante , Congressos como Assunto , Análise Custo-Benefício , Países em Desenvolvimento/economia , Procedimentos Cirúrgicos do Sistema Digestório/economia , Custos de Medicamentos , Detecção Precoce de Câncer , Medicina Baseada em Evidências , Fidelidade a Diretrizes , Custos de Cuidados de Saúde , Acessibilidade aos Serviços de Saúde , Disparidades em Assistência à Saúde , Hepatectomia , Vacinas contra Hepatite B/uso terapêutico , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/prevenção & controle , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/prevenção & controle , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/economia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/prevenção & controle , Neoplasias Hepáticas/virologia , Transplante de Fígado , Oncologia/economia , Oncologia/normas , Terapia Neoadjuvante , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Serviços Preventivos de Saúde/economia , Radioterapia Adjuvante , Fatores de Risco , Resultado do Tratamento
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