title: Using expression profiling to understand the effects of chronic cadmium exposure on MCF-7 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 from exposing breast cancer cells to cadmium for over 6 months (MCF-7-Cd4, -Cd6, -Cd7, -Cd8 and -Cd12), this study aims to identify gene expression signatures associated with chronic cadmium exposure. Our results demonstrate that prolonged cadmium 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 cells from cadmium exposed cells. The results presented in this study offer insights into the cellular and molecular impacts of cadmium on breast cancer and emphasize the importance of studying chronic cadmium exposure as one possible mechanism of promoting breast cancer progression.
authors.affiliation: Systems Biology Research Centre - Bioinformatics, School of Bioscience, University of Skövde, Skövde, Sweden.
authors.forename: Zelmina
authors.initials: Z
authors.lastname: Lubovac-Pilav
authors.affiliation: Systems Biology Research Centre - Bioinformatics, School of Bioscience, University of Skövde, Skövde, Sweden.
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Borràs
authors.affiliation: Department of Natural Sciences and Mathematics, Dominican University of California, San Rafael, California, United States of America.
authors.forename: Esmeralda
authors.initials: E
authors.lastname: Ponce
authors.affiliation: Department of Natural Sciences and Mathematics, Dominican University of California, San Rafael, California, United States of America ; College of Pharmacy, Touro University of California, Vallejo, California, United States of America.
authors.forename: Maggie C
authors.initials: MC
authors.lastname: Louie
mesh_terms: D002104:Cadmium / Q000633:toxicity*; D016000:Cluster Analysis; D017931:DNA Primers / Q000235:genetics; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D006801:Humans; D061986:MCF-7 Cells / Q000187:drug effects*; D046228:Microarray Analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D017931:DNA Primers; D002104:Cadmium