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The effects of chronic cadmium exposure on gene expression in MCF7 breast cancer cells

ABSTRACT: Cadmium is a metalloestrogen known to activate the estrogen receptor and promote breast cancer cell growth. Previous studies have implicated cadmium in the development of more malignant tumors; however the molecular mechanisms behind this cadmium-induced malignancy remain elusive. Using clonal cell lines derived by exposing breast cancer cells to cadmium for over 6 month (MCF7-Cd4, -Cd6, -Cd7, -Cd8 and -Cd12), this study aims to identify gene expression signatures associated with chronic cadmium exposure. Our results demonstrate that prolonged exposure does not merely result in the deregulation of genes but actually leads to a distinctive expression profile. The genes deregulated in cadmium-exposed cells are involved in multiple biological processes (i.e cell growth, apoptosis, etc.) and molecular functions (i.e. cadmium/metal ion binding, transcription factor activity, etc). Hierarchical clustering demonstrates that the five clonal cadmium cell lines share a common gene expression signature of breast cancer associated genes, clearly differentiating control from cadmium exposed cells. The results presented in this study offer insights into the cellular and molecular impacts of cadmium on breast cancer carcinogenesis and emphasize the importance of studying chronic cadmium exposure as one possible mechanism of promoting breast cancer progression.

ORGANISM(S): Homo sapiens

PROVIDER: GSE52404 | GEO | 2013/11/16

SECONDARY ACCESSION(S): PRJNA227800

REPOSITORIES: GEO

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The effects of chronic cadmium exposure on gene expression in MCF7 breast cancer cells

Project description:Cadmium is a metalloestrogen known to activate the estrogen receptor and promote breast cancer cell growth. Previous studies have implicated cadmium in the development of more malignant tumors; however the molecular mechanisms behind this cadmium-induced malignancy remain elusive. Using clonal cell lines derived by exposing breast cancer cells to cadmium for over 6 month (MCF7-Cd4, -Cd6, -Cd7, -Cd8 and -Cd12), this study aims to identify gene expression signatures associated with chronic cadmium exposure. Our results demonstrate that prolonged exposure does not merely result in the deregulation of genes but actually leads to a distinctive expression profile. The genes deregulated in cadmium-exposed cells are involved in multiple biological processes (i.e cell growth, apoptosis, etc.) and molecular functions (i.e. cadmium/metal ion binding, transcription factor activity, etc). Hierarchical clustering demonstrates that the five clonal cadmium cell lines share a common gene expression signature of breast cancer associated genes, clearly differentiating control from cadmium exposed cells. The results presented in this study offer insights into the cellular and molecular impacts of cadmium on breast cancer carcinogenesis and emphasize the importance of studying chronic cadmium exposure as one possible mechanism of promoting breast cancer progression. To understand the effects of chronic cadmium exposure on gene expression in breast cancer, two control MCF7 parental cell lines and five different clonal cadmium-adapted cell lines (MCF7-Cd4, -Cd6, -Cd7, -Cd8, and -Cd12) - previously derived from cells chronically exposed to cadmium - were used for microarray analysis.

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