• Molecules and Cells
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• 제40권3호
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• pp.202-210
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• 2017

The nonstructural protein 5A (NS5A) encoded by the human hepatitis C virus (HCV) RNA genome is a multifunctional phosphoprotein. To analyse the influence of NS5A on apoptosis, we established an Hep-NS5A cell line (HepG2 cells that stably express NS5A) and induced apoptosis using tumour necrosis factor $(TNF)-{\alpha}$. We utilised the MTT assay to detect cell viability, real-time quantitative polymerase chain reaction and Western blot to analyse gene and protein expression, and a luciferase reporter gene experiment to investigate the targeted regulatory relationship. Chromatin immunoprecipitation was used to identify the combination of $NF-{\kappa}B$ and miR-503. We found that overexpression of NS5A inhibited $TNF-{\alpha}$-induced hepatocellular apoptosis via regulating miR-503 expression. The cell viability of the $TNF-{\alpha}$ induced Hep-mock cells was significantly less than the viability of the $TNF-{\alpha}$ induced Hep-NS5A cells, which demonstrates that NS5A inhibited $TNF-{\alpha}$-induced HepG2 cell apoptosis. Under $TNF-{\alpha}$ treatment, miR-503 expression was decreased and cell viability and B-cell lymphoma 2 (bcl-2) expression were increased in the Hep-NS5A cells. Moreover, the luciferase reporter gene experiment verified that bcl-2 was a direct target of miR-503, NS5A inhibited $TNF{\alpha}$-induced $NF-{\kappa}B$ activation and $NF-{\kappa}B$ regulated miR-503 transcription by combining with the miR-503 promoter. After the Hep-NS5A cells were transfected with miR-503 mimics, the data indicated that the mimics could reverse $TNF-{\alpha}$-induced cell apoptosis and blc-2 expression. Collectively, our findings suggest a possible molecular mechanism that may contribute to HCV treatment in which NS5A inhibits $NF-{\kappa}B$ activation to decrease miR-503 expression and increase bcl-2 expression, which leads to a decrease in hepatocellular apoptosis.

• Asian Pacific Journal of Cancer Prevention
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• 제13권5호
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• pp.1917-1921
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• 2012

Background: Colorectal cancer is one of the leading causes of mortality worldwide. Genome wide analysis studies have identified sequence mutations causing loss-of-function that are associated with disease occurrence and severity. Epigenetic modifications, such DNA methylation, have also been implicated in many cancers but have yet to be examined in the East Asian population of colorectal cancer patients. Methods: Biopsies of tumors and matched non-cancerous tissue types were obtained and genomic DNA was isolated and subjected to the bisulphite conversion method for comparative DNA methylation analysis on the Illumina Infinium HumanMethylation27 BeadChip. Results: Totals of 258 and 74 genes were found to be hyper- and hypo-methylated as compared to the individual's matched control tissue. Interestingly, three genes that exhibited hypermethylation in their promoter regions, CMTM2, ECRG4, and SH3GL3, were shown to be significantly associated with colorectal cancer in previous studies. Using heatmap cluster analysis, eight hypermethylated and 10 hypomethylated genes were identified as significantly differentially methylated genes in the tumour tissues. Conclusions: Genome-wide methylation profiling facilitates rapid and simultaneous analysis of cancerous cells which may help to identify methylation markers with high sensitivity and specificity for diagnosis and prognosis. Our results show the promise of the microarray technology in identification of potential methylation biomarkers for colorectal cancers.

• Asian Pacific Journal of Cancer Prevention
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• 제13권5호
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• pp.1971-1975
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• 2012

Overexpression of several aquaporins (AQPs) has been reported in different types of human cancer but their role in carcinogenesis, for example in the cervix, have yet to be clearly defined. In this study, expression of AQPs in cervical carcinomawas investigated by real-time PCR, immunofluorescent and immunohistochemical assays and evaluated for correlations with clinicopathologic variables. AQP1, 3, 8 exhibited differential expression in cervical carcinoma, corresponding CIN and mild cervicitis. AQP1 was predominantly localized in the microvascular endothelial cell in the stroma of mild cervicitis, CIN and cervical carcinoma. AQP3 and AQP8 were localized in the membrane of normal squamous epithelium and carcinoma cells, local signals being more common than diffuse staining. AQP1 and AQP3 expression was remarkably stronger in cervical cancer than in mild cervicitis and CIN2-3 (P<0.05). AQP8 expression was highest in CIN2-3 (91.7%), but levels in cervical carcinoma were also higher than in mild cervicitis. AQP1, AQP3, AQP8 expression significantly increased in advanced stage, deeper infiltration, metastatic lymph nodes and larger tumor volume (P<0.05). Our findings showed that AQPs might play important roles in cervical carcinogenesis and tumour progression in Uygur women.

• Molecular & Cellular Toxicology
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• 제4권2호
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• pp.106-112
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• 2008

Parkinson's disease (PD) progresses severely by a gradual loss of dopaminergic neurons in the substantia nigra (SN). Epidemiological studies showed that the incidences of PD were reduced by smoking of which the major component, nicotine might be neuroprotective. But the function of nicotine, which might suppress the incidences of PD, is still unknown. Fortunately, recently it was reported that a glial reaction and inflammatory processes might participate in a selective loss of dopaminergic neurons in the SN. The levels of tumour necrosis factor (TNF)-${\alpha}$ synthesised by astrocytes and microglia are elevated in striatum and cerebrospinal fluid (CSF) in PD. TNF-${\alpha}$ kills the cultured dopaminergic neurons through the apoptosis mechanism. TNF-${\alpha}$ release from glial cells may mediate progression of nigral degeneration in PD. Nicotine pretreatment considerably decreases microglial activation with significant reduction of TNF-${\alpha}$ mRNA expression and TNF-${\alpha}$ release induced by lipopholysaccharide (LPS) stimulation. Thus, this study was intended to explore the role of nicotine pretreatment to inhibit the expressions of TNF-${\alpha}$ mRNA in human fetal astrocytes (HFA) stimulated with IL-$1{\beta}$. The results are as follows: HFA were pretreated with 0.1, 1, and $10{\mu}g/mL$ of nicotine and then stimulated with IL-$1{\beta}$ (100 pg/mL) for 2h. The inhibitory effect of nicotine on expressions of TNF-${\alpha}$ mRNA in HFA with pretreated $0.1{\mu}g/mL$ of nicotine was first noted at 8hr, and the inhibitory effect was maximal at 12 h. The inhibitory effect at $1{\mu}g/mL$ of nicotine was inhibited maximal at 24 h. Cytotoxic effects of nicotine were noted above $10{\mu}g/mL$ of nicotine. Moreover, Nicotine at 0.1, 1 and $10{\mu}g/mL$concentrations significantly inhibited IL-$1{\beta}$-induced TF-${\kappa}B$ activation. Collectively, these results indicate that in activated HFA, nicotine may inhibit the expression of TNF-${\alpha}$ mRNA through the pathway which suppresses the NF-${\kappa}B$ activation. This study suggests that nicotine might be neuroprotective to dopaminergic neurons in the SN and reduce the incidences of PD.

• Asian Pacific Journal of Cancer Prevention
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• 제15권15호
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• pp.6397-6403
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• 2014

Background: Aberrant promoter hypermethylation has been recognized in human breast carcinogenesis as a frequent molecular alteration associated with the loss of expression of a number of key regulatory genes and may serve as a biomarker. The E-cadherin gene (CDH1), mapping at chromosome 16q22, is an intercellular adhesion molecule in epithelial cells, which plays an important role in establishing and maintaining intercellular connections. The aim of our study was to assess the methylation pattern of CDH1 and to correlate it with the expression of E-cadherin, clinicopathological parameters and hormone receptor status in breast cancer patients of Kashmir. Materials and Methods: Methylation specific PCR (MSP) was used to determine the methylation status of CDH1 in 128 invasive ductal carcinomas (IDCs) paired with the corresponding normal tissue samples. Immunohistochemistry was used to study the expression of E-cadherin, ER and PR. Results: CDH1 hypermethylation was detected in 57.8% of cases and 14.8% of normal adjacent controls. Reduced levels of E-cadherin protein were observed in 71.9% of our samples. Loss of E-cadherin expression was significantly associated with the CDH1 promoter region methylation (p<0.05, OR=3.48, CI: 1.55-7.79). Hypermethylation of CDH1 was significantly associated with age at diagnosis (p=0.030), tumor size (p=0.008), tumor grade (p=0.024) and rate of node positivity or metastasis (p=0.043). Conclusions: Our preliminary findings suggest that abnormal CDH1 methylation occurs in high frequencies in infiltrating breast cancers associated with a decrease in E-cadherin expression. We found significant differences in tumor-related CDH1 gene methylation patterns relevant to tumor grade, tumor size, nodal involvement and age at diagnosis of breast tumors, which could be extended in future to provide diagnostic and prognostic information.

• Radiation Oncology Journal
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• 제20권2호
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• pp.93-99
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• 2002

목적 : 두개내 배아종은 방사선치료 단독으로도 완치율이 높은 종양이나 방사선치료로 인한 부작용의 감소를 위해 현재 서울대학교 병원에서는 전보조화학요법 후 방사선치료를 하고 있으며 이 환자들의 치료 성적과 부작용을 분석하고자 하였다. 대상 및 방법 : 1995년에서 2001년까지 치료를 받은 두개내 배아종으로 조직학적으로 진단된 18명의 환자를 대상으로 하였다. 12명은 BEP (bleomycin, VP-16, cisplatin) 항암치료, 5명은 9921A (cisplatin, cyclophosphamide, VP-16, vincristine) 항암치료, 1명은 EP (VP-16, cisplatin) 항암치료를 받았고 5명은 두개척수조사, 1명은 두개방사선조사, 12명은 종양 부위에만 방사선치료를 받았다. 원발 종양에 조사된 방사선량은 39.6에서 54 Gy였다. 결과 : 남자는 16명, 여자는 2명이었고 중간 나이는 16세였다. 자기공명영상 상 12명은 송과체에, 각각 1명에서 안상, 시상, 대뇌기저핵에 원발성 종괴가 있었고 3명에서 다발성 종괴가 있었다. 6명은 뇌실 내 전이 소견이 보였고 3명은 뇌척추액검사 상 종양 세포가 관찰되었고 2명에서는 척수 자기공명영상에서 전이 소견이 있었다. 종양지표검사 상 1명에서 $\beta-human$ chorionic gonadotropin의 수치가 44 mlU/mL로 상승되어 있었다. 항암치료 후 5명은 완전 관해, 12명은 부분 관해를 보였고, 1명은 반응이 없었다. 현재 중앙 추적 기간 20개월로 17명은 무병 상태로 관찰되고 있고 1명은 bleomycin으로 인한 것으로 추정되는 폐의 부작용으로 사망하였다. 사망한 환자를 제외한 다른 환자들은 방사선치료 후 모두 완전 관해 상태이다. 6명에서 백혈구 감소로 인한 감염이 발생하였으며 $3\~4$도의 혈액학적 부작용이 11명에서 발생하였다. 방사선조사 중 두개척수조사를 받은 5명의 환자를 제외한 나머지 환자에서는 2도 이상의 부작용은 보이지 않았다. 결론 : 서울대학교병원에서의 전보조화학요법 후 방사선치료는 기존의 보고와 마찬가지로 높은 관해율을 보이고 있고 항암치료로 인한 치료 중이나 치료 후의 부작용의 정도와 빈도는 다른 보고와 비슷하였다. 방사선이나 항암치료로 인한 만성 부작용에 대해서는 좀더 관찰이 필요하며 이 결과가 나온 후에 두개내 배아종에서 가장 적절한 치료에 대해 결론을 내릴 숱 있을 것으로 보인다.