Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Claudin-7 is frequently overexpressed in ovarian cancer and promotes invasion

ABSTRACT: Claudins are tight junction proteins that are involved in tight junction formation and function. Previous studies have shown that claudin-7 is frequently upregulated in epithelial ovarian cancer (EOC) along with claudin-3 and claudin-4. Here, we investigate in detail the expression patterns of claudin-7, as well as its possible functions in EOC. Initially a total of 95 ovarian tissue samples (7 normal ovarian tissues, 65 serous carcinomas, 11 clear cell carcinomas, 8 endometrioid carcinomas and 4 mucinous carcinomas) were studied for claudin-7 expression using RT-PCR analysis. The gene for claudin-7, CLDN7, was found to be significantly upregulated in all the tumor tissue samples studied. Similarly, immunohistochemical analysis and western blotting showed that claudin-7 protein was significantly overexpressed in the vast majority of EOCs. Two cell lines(OVCAR-2 and OVCA420) were chosen for microarray based gene expression analysis using small interfering RNA-mediated(SiRNA) knockdown of claudin-7. This treatment led to significant changes in gene expression that was validated by RT-PCR and immunoblotting. Ovarian cancer lines OVCA420 and OVCAR-2 were cultured in duplicate in McCoy’s 5A growth medium (Invitrogen) supplemented with 10% fetal bovine serum (FBS) and antibiotics (100 units/ml penicillin and 100 mg/ml streptomycin). Cells cultured in 6-well plates were transfected with either Claudin-7 specific siRNA oligos duplexes (Ambion, Inc.Austin, TX) or control siRNA #1 (Dharmacon) using LipofectAMINE 2000 (Invitrogen). Cells were treated for 72 hours to allow maximum knockdown, after which they were harvested for RNA preparation. Total RNA, was extracted using Trizol, quality and quantity were checked using the Agilent 2100 Bioanalyzer with RNA 6000 Nano chip, (Agilent Technologies UK Ltd, West Lothian, UK). Biotinylated cRNA was generated using the Illumina TotalPrep RNA Amplification Kit (Ambion; Austin, TX) starting with approximately 500 ng total RNA. Hybridization of the cRNA was to the Sentrix HumanRef-8 Expression BeadChip (Illumina, Inc., San Diego, CA). Microarray data processing and analysis was performed using Illumina Bead Studio software. Hierarchical clustering analysis of the significant genes was done using the JMP 6.0.0 software. Validation of the expression patterns of selected genes was performed using RT-PCR.

ORGANISM(S): Homo sapiens

SUBMITTER: Kevin Becker

PROVIDER: E-GEOD-26055 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

Claudin-7 is frequently overexpressed in ovarian cancer and promotes invasion.

Dahiya Neetu N Becker Kevin G KG Wood William H WH Zhang Yongqing Y Morin Patrice J PJ

PloS one 20110715 7

<h4>Background</h4>Claudins are tight junction proteins that are involved in tight junction formation and function. Previous studies have shown that claudin-7 is frequently upregulated in epithelial ovarian cancer (EOC) along with claudin-3 and claudin-4. Here, we investigate in detail the expression patterns of claudin-7, as well as its possible functions in EOC.<h4>Methodology/principal findings</h4>A total of 95 ovarian tissue samples (7 normal ovarian tissues, 65 serous carcinomas, 11 clear ...[more]

PMID: 21789222

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Dataset Information

Claudin-7 is frequently overexpressed in ovarian cancer and promotes invasion

Publications

Claudin-7 is frequently overexpressed in ovarian cancer and promotes invasion.

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