Dataset Information

The Study of DNA Methylation of bax Gene Promoter in Breast and Colorectal Carcinoma Cell Lines.

ABSTRACT: BACKGROUND:The Bcl-2 protein family members have known as essential controllersof mitochondrial pathway of apoptosis. Bax has been implicated as potential tumor suppressor in certain solid tumors such as breast and colorectal carcinoma. DNA methylation of promoter associated CpG islands has known as a common mechanism for gene inactivation in tumor cells. METHODS:The Methylation Specific PCR (MSP) has used to find the methylation profile of the bax gene promoter CpG islands in colorectal and breast cancer cell lines. RESULTS:We have not detected any kind of "CpG islands hypermethylation" in promoter region of the bax gene in T47D, MCF7 (as ER positive), MDA-MB-231 and MDA-MB-468 (as ER negative) breast carcinoma-derived cell lines and colorectal cancer cell lines H29 and Caco II. CONCLUSION:It seems that CpG island methylation could not play the main role in down-regulation of bax gene in breast and colon cancers.

SUBMITTER: Alipour M

PROVIDER: S-EPMC4142912 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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The Study of DNA Methylation of bax Gene Promoter in Breast and Colorectal Carcinoma Cell Lines.

Alipour Mohsen M Zargar Seyed Jalal SJ Safarian Shahrokh S Fouladdel Shamileh S Azizi Ebrahim E Jafargholizadeh Naser N

Iranian journal of cancer prevention 20130101 2

<h4>Background</h4>The Bcl-2 protein family members have known as essential controllersof mitochondrial pathway of apoptosis. Bax has been implicated as potential tumor suppressor in certain solid tumors such as breast and colorectal carcinoma. DNA methylation of promoter associated CpG islands has known as a common mechanism for gene inactivation in tumor cells.<h4>Methods</h4>The Methylation Specific PCR (MSP) has used to find the methylation profile of the bax gene promoter CpG islands in col ...[more]

PMID: 25250112

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Project description:BackgroundEpithelial ovarian carcinoma is a significant cause of cancer mortality in women worldwide and in the United States. Epithelial ovarian cancer comprises several histological subtypes, each with distinct clinical and molecular characteristics. The natural history of this heterogeneous disease, including the cell types of origin, is poorly understood. This study applied recently developed methods for high-throughput DNA methylation profiling to characterize ovarian cancer cell lines and tumors, including representatives of three major histologies.Methodology/principal findingsWe obtained DNA methylation profiles of 1,505 CpG sites (808 genes) in 27 primary epithelial ovarian tumors and 15 ovarian cancer cell lines. We found that the DNA methylation profiles of ovarian cancer cell lines were markedly different from those of primary ovarian tumors. Aggregate DNA methylation levels of the assayed CpG sites tended to be higher in ovarian cancer cell lines relative to ovarian tumors. Within the primary tumors, those of the same histological type were more alike in their methylation profiles than those of different subtypes. Supervised analyses identified 90 CpG sites (68 genes) that exhibited 'subtype-specific' DNA methylation patterns (FDR<1%) among the tumors. In ovarian cancer cell lines, we estimated that for at least 27% of analyzed autosomal CpG sites, increases in methylation were accompanied by decreases in transcription of the associated gene.SignificanceThe significant difference in DNA methylation profiles between ovarian cancer cell lines and tumors underscores the need to be cautious in using cell lines as tumor models for molecular studies of ovarian cancer and other cancers. Similarly, the distinct methylation profiles of the different histological types of ovarian tumors reinforces the need to treat the different histologies of ovarian cancer as different diseases, both clinically and in biomarker studies. These data provide a useful resource for future studies, including those of potential tumor progenitor cells, which may help illuminate the etiology and natural history of these cancers.

Dataset Information

The Study of DNA Methylation of bax Gene Promoter in Breast and Colorectal Carcinoma Cell Lines.

Publications

The Study of DNA Methylation of bax Gene Promoter in Breast and Colorectal Carcinoma Cell Lines.

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