• Title/Summary/Keyword: EGFR gene expression

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Knockdown of GCF2/LRRFIP1 by RNAi Causes Cell Growth Inhibition and Increased Apoptosis in Human Hepatoma HepG2 Cells

  • Li, Jing-Ping;Cao, Nai-Xia;Jiang, Ri-Ting;He, Shao-Jian;Huang, Tian-Ming;Wu, Bo;Chen, De-Feng;Ma, Ping;Chen, Li;Zhou, Su-Fang;Xie, Xiao-Xun;Luo, Guo-Rong
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.6
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    • pp.2753-2758
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    • 2014
  • Background: GC-binding factor 2 (GCF2) is a transcriptional regulator that represses transcriptional activity of the epidermal growth factor receptor (EGFR) by binding to a specific GC-rich sequence in the EGFR gene promoter. In addition to this function, GCF2 has also been identified as a tumor-associated antigen and regarded as a potentially valuable serum biomarker for early human hepatocellular carcinoma (HCC) diagnosis. GCF2 is high expressed in most HCC tissues and cell lines including HepG2. This study focused on the influence of GCF2 on cell proliferation and apoptosis in HepG2 cells. Materials and Methods: GCF2 expression at both mRNA and protein levels in HepG2 cells was detected with reverse transcription (RT) PCR and Western blotting, respectively. RNA interference (RNAi) technology was used to knock down GCF2 mRNA and protein expression. Afterwards, cell viability was analyzed with a Cell Counting Kit-8 (CCK-8), and cell apoptosis and caspase 3 activity by flow cytometry and with a Caspase 3 Activity Kit, respectively. Results: Specific down-regulation of GCF2 expression caused cell growth inhibition, and increased apoptosis and caspase 3 activity in HepG2 cells. Conclusions: These primary results suggest that GCF2 may influence cell proliferation and apoptosis in HepG2 cells, and also provides a molecular basis for further investigation into the possible mechanism at proliferation and apoptosis in HCC.

Tumorigenesis after Injection of Lung Cancer Cell Line (SW-900 G IV) into the Pleural Cavity of Nude Mice (누드마우스의 흉강에 폐암세포주의 주입에 의한 종양형성과 HER2/neu와 TGF-${\beta}_1$의 발현)

  • Park, Eok-Sung;Kim, Song-Myung;Kim, Jong-In
    • Journal of Chest Surgery
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    • v.43 no.6
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    • pp.588-595
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    • 2010
  • Background: Base on types of tumor, the types of expressed tumor is diverse and the difference in its expression rate is even more various. Due to such reasons an animal model is absolutely needed for a clinical research of lung cancer. The author attempted oncogenesis by cultivating a cell line of non-small cell carcinoma and then injecting it inside thoracic cavities of nude mice. The author conducted quantitative analyses of HER2/neu tumor gene - an epidermal growth factor receptor (EGFR) related to lung cancer, and TGF-${\beta}_1$, which acts as a resistance to cell growth inhibition and malignant degeneration. In order to investigate achievability of the oncogenesis, histological changes and the expression of cancer gene in case of orthotopic lung cancer is necessary. Material and Method: Among 20 immunity-free male BALB/c, five nude mice were selected as the control group and rest as the experimental group. Their weights ranged from 20 to 25 gm (Orient, Japan). After injection of lung cancer line (SW900 G IV) into the pleural cavity of nude mice, They were raised at aseptic room for 8 weeks. HER2/neu was quantitatively analyzed by separating serum from gathered blood via chemiluminiscent immunoassay (CLIA), and immunosandwitch method was applied to quantitatively analyze TGF-${\beta}_1$. SPSS statistical program (SPSS Version 10.0, USA) was implemented for statistical analysis. Student T test was done, and cases in which p-value is less than 0.05 were considered significant. Result: Even after lung cancer was formed in the normal control group or after intentionally injected lung cancer cell line, no amplification of HER2/neu gene showed reaction. However, the exact quantity of TGF-${\beta}_1$ was $28,490{\pm}8,549pg/mL$, and the quantity in the group injected with lung cancer cell was $42,362{\pm}14,449pg/mL$, meaning 1.48 times highly Significant (p<0.483). It proved that HER2/neu gene TGF-${\beta}_1$ had no meaningful interconnection. Conclusion: TGF-${\beta}_1$ gene expressed approximately 1.48 times amplification in comparison to the control group. The amplification of TGF-${\beta}_1$ meant somatic recuperation inhibition mechanism due to carcinogenesis in nude mice was definitely working. It may be implemented as a quantitative analysis that allows early detection of lung cancer in human body.

PKHD1 Gene Silencing May Cause Cell Abnormal Proliferation through Modulation of Intracellular Calcium in Autosomal Recessive Polycystic Kidney Disease

  • Yang, Ji-Yun;Zhang, Sizhong;Zhou, Qin;Guo, Hong;Zhang, Ke;Zheng, Rong;Xiao, Cuiying
    • BMB Reports
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    • v.40 no.4
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    • pp.467-474
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    • 2007
  • Autosomal recessive polycystic kidney disease (ARPKD) is one of the important genetic disorders in pediatric practice. Mutation of the polycystic kidney and hepatic disease gene 1 (PKHD1) was identified as the cause of ARPKD. The gene encodes a 67-exon transcript for a large protein of 4074 amino acids termed fibrocystin, but its function remains unknown. The neoplastic-like in cystic epithelial proliferation and the epidermal growth factor/epidermal growth factor receptor (EGF/EGFR) axis overactivity are known as the most important characteristics of ARPKD. Since the misregulation of $Ca^{2+}$ signaling may lead to aberrant structure and function of the collecting ducts in kidney of rat with ARPKD, present study aimed to investigate the further mechanisms of abnormal proliferation of cystic cells by inhibition of PKHD1 expression. For this, a stable PKHD1-silenced HEK-293T cell line was established. Then cell proliferation rates, intracellular $Ca^{2+}$ concentration and extracellular signal-regulated kinase 1/2 (ERK1/2) activity were assessed after treatment with EGF, a calcium channel blocker and agonist, verapamil and Bay K8644. It was found that PKHD1-silenced HEK-293T cell lines were hyperproliferative to EGF stimulation. Also PKHD1-silencing lowered the intracellular $Ca^{2+}$ and caused EGF-induced ERK1/2 overactivation in the cells. An increase of intracellular $Ca^{2+}$ in PKHD1-silenced cells repressed the EGF-dependent ERK1/2 activation and the hyperproliferative response to EGF stimulation. Thus, inhibition of PKHD1 can cause EGF-induced excessive proliferation through decreasing intracellular $Ca^{2+}$ resulting in EGF-induced ERK1/2 activation. Our results suggest that the loss of fibrocystin may lead to abnormal proliferation in kidney epithelial cells and cyst formation in ARPKD by modulation of intracellular $Ca^{2+}$.

Network Pharmacology Analysis and Efficacy Prediction of GunryeongTang Constituents in Diabetic Complications (당뇨 합병증과 군령탕 구성성분의 네트워크 약리학 분석 및 효능 예측)

  • Jung Joo Yoon;Hye Yoom Kim;Ai Lin Tai;Ho Sub Lee;Dae Gill Kang
    • Herbal Formula Science
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    • v.32 no.1
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    • pp.11-28
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    • 2024
  • Objectives : GunRyeong-Tang(GRT) is a traditional herbal prescription that combines Oryeongsan and Sagunja-tang. This study employed network analysis methods on the components of GRT and target genes related to diabetes complications to predict the improvement effects of GRT on diabetes complications. Methods : The collection of active compounds of GRT and related target genes involved the utilization of public databases and the PubChem database. We selected diabetes complication-related genes using GeneCards and confirmed their correlation through comparative analysis with the target genes of GRT. We constructed a network using Cytoscape 3.9.1 and conducted topological analysis. To predict the mechanism, we performed functional enrichment analysis based on Gene Ontology (GO) biological processes and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Results : Through network analysis, 234 active compounds and 1361 related genes were collected from GRT. A total of 9,136 genes related to diabetes complications were collected, and 1,039 target genes overlapping with the components of GRT were identified. The core genes of this network were TP53, INS, AKT1, ALB, and EGFR. In addition, GRT significantly reduced the H9c2 cell size and the expression of myocardial hypertrophy biomarkers (ANP, BNP), which were increased by high glucose (HG). Conclusions : Through this study, we were able to predict the activity and mechanism of action of GRT on diabetes and diabetic complications, and confirmed the potential of GRT as a treatment for diabetes complications through the effect of GRT on improving myocardial hypertrophy for diabetic cardiomyopathy.

Muc5ac Gene Expression Induced by Cigarette Smoke is Mediated Via a Pathway Involving ERK1/2 and p38 MAPK (담배 연기에 의한 Muc5ac 유전자 발현에 관여하는 세포 내 신호 전달 경로로서의 ERK1/2와 p38 MAPK)

  • Kim, Yong Hyun;Yoon, Hyoung Kyu;Kim, Chi Hong;Ahn, Joong Hyun;Kwon, Soon Seog;Kim, Young Kyoon;Kim, Kwan Hyoung;Moon, Hwa Sik;Park, Sung Hak;Song, Jeong Sup;Cho, Kyung Sook
    • Tuberculosis and Respiratory Diseases
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    • v.58 no.6
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    • pp.590-599
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    • 2005
  • Object : Cigarette smoking is a major cause of mucus hypersecretion, which is a pathophysiological feature of many inflammatory airway diseases. Mucins, which are an important part of the airway mucus, are synthesized from the Muc gene in airway epithelial cells. However, the signaling pathways for cigarette smoke-induced mucin synthesis are unknown. The aim of this study was to determine the signal pathway for smoking induced Muc5ac gene expression. Methods : A549 cells were cultured and transiently transfected with the Muc5ac promoter fragment. These cells were stimulated with 5% cigarette smoke extract (CSE) alone or with CSE after a pretreatment with various signal transduction pathway inhibitors (AG1478, PD98059 and SB203580). The Muc5ac promoter activity was examined using the luciferase reporter system, and the level of phosphorylated EGFR, ERK1/2, p38 MAPK and JNK were all examined using Western blot analysis. Muc5ac mRNA expression was also examined using reverse transcriptase polymerase chain reactions (RT-PCR). Results : 1. The peak level of luciferase activity of the Muc5ac promoter was observed at 5% concentration and after 3 hours of incubation with the CSE. The level of EGFR phosphorylation and the luciferase activity of the transfected cells caused by the CSE were significantly suppressed by AG1478 or PD98059 (P<0.01). 2. CSE phosphorylated ERK1/2 or p38 MAPK but not JNK. The Muc5ac mRNA expression level was increased by the CSE but that was suppressed by PD98059 or AG1478. 3. The CSE-induced phosphorylation of ERK1/2 was blocked by PD98059 and that of p38 MAPK was blocked by either PD98059 or SB203580. Either PD98059 or SB203580 suppressed the luciferase activity of the transfected cells (P<0.0001). Conclusion : The Muc5ac mRNA expression level was increased by the CSE. The increased CSE-induced transcriptional activity was mediated via EGF receptor activation, which led to ERK1/2 and p38 MAPK phosphorylation.

Clinicopathological Characteristics of Triple Negative Breast Cancer at a Tertiary Care Hospital in India

  • Dogra, Atika;Doval, Dinesh Chandra;Sardana, Manjula;Chedi, Subhash Kumar;Mehta, Anurag
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.24
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    • pp.10577-10583
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    • 2015
  • Background: Triple-negative breast cancer (TNBC), characterized by the lack of expression of estrogen receptor, progesterone receptor and human epidermal growth factor receptor-2, is typically associated with a poor prognosis. The majority of TNBCs show the expression of basal markers on gene expression profiling and most authors accept TNBC as basal-like (BL) breast cancer. However, a smaller fraction lacks a BL phenotype despite being TNBC. The literature is silent on non-basal-like (NBL) type of TNBC. The present study was aimed at defining behavioral differences between BL and NBL phenotypes. Objectives: i) Identify the TNBCs and categorize them into BL and NBL breast cancer. ii) Examine the behavioral differences between two subtypes. iii) Observe the pattern of treatment failure among TNBCs. Materials and Methods: All TNBC cases during January 2009-December 2010 were retrieved. The subjects fitting the inclusion criteria of study were differentiated into BL and NBL phenotypes using surrogate immunohistochemistry with three basal markers $34{\beta}E12$, c-Kit and EGFR as per the algorithm defined by Nielsen et al. The detailed data of subjects were collated from clinical records. The comparison of clinicopathological features between two subgroups was done using statistical analyses. The pattern of treatment failure along with its association with prognostic factors was assessed. Results: TNBC constituted 18% of breast cancer cases considered in the study. The BL and NBL subtypes accounted for 81% and 19% respectively of the TNBC group. No statistically significant association was seen between prognostic parameters and two phenotypes. Among patients with treatment failure, 19% were with BL and 15% were with NBL phenotype. The mean disease free survival (DFS) in groups BL and NBL was 30.0 and 37.9 months respectively, while mean overall survival (OS) was 31.93 and 38.5 months respectively. Treatment failure was significantly associated with stage (p=.023) among prognostic factors. Conclusions: Disease stage at presentation is an important prognostic factor influencing the treatment failure and survival among TNBCs. Increasing tumor size is related to lymph node positivity. BL tumors have a more aggressive clinical course than that of NBL as shown by shorter DFS and OS, despite having no statistically significant difference between prognostic parameters. New therapeutic alternatives should be explored for patients with this subtype of breast cancer.