title: Chronic cadmium exposure stimulates SDF-1 expression in an ERα dependent manner.
abstract: Cadmium is an omnipotent environmental contaminant associated with the development of breast cancer. Studies suggest that cadmium functions as an endocrine disruptor, mimicking the actions of estrogen in breast cancer cells and activating the receptor to promote cell growth. Although acute cadmium exposure is known to promote estrogen receptor-mediated gene expression associated with growth, the consequence of chronic cadmium exposure is unclear. Since heavy metals are known to bioaccumulate, it is necessary to understand the effects of prolonged cadmium exposure. This study aims to investigate the effects of chronic cadmium exposure on breast cancer progression. A MCF7 breast cancer cell line chronically exposed to 10(-7) M CdCl2 serves as our model system. Data suggest that prolonged cadmium exposures result in the development of more aggressive cancer phenotypes - increased cell growth, migration and invasion. The results from this study show for the first time that chronic cadmium exposure stimulates the expression of SDF-1 by altering the molecular interactions between ERα, c-jun and c-fos. This study provides a mechanistic link between chronic cadmium exposure and ERα and demonstrates that prolonged, low-level cadmium exposure contributes to breast cancer progression.
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.forename: Natalie B
authors.initials: NB
authors.lastname: Aquino
authors.forename: Maggie C
authors.initials: MC
authors.lastname: Louie
mesh_terms: D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D002104:Cadmium / Q000633:toxicity*; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D054377:Chemokine CXCL12 / Q000096:biosynthesis*; D004305:Dose-Response Relationship, Drug; D047628:Estrogen Receptor alpha / Q000378:metabolism*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D006801:Humans; D009361:Neoplasm Invasiveness; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism
chemical_list: C515255:CXCL12 protein, human; D054377:Chemokine CXCL12; C506487:ESR1 protein, human; D047628:Estrogen Receptor alpha; D016760:Proto-Oncogene Proteins c-fos; D016755:Proto-Oncogene Proteins c-jun; D002104:Cadmium