Role of alterations of gene expression in extracellular vesicles after PCB exposure in breast cancer

Abstract:

Polychlorinated biphenyls (PCBs) are contaminants in Lake Erie that travel through food webs eventually making their way into game fish consumed by Erie County residents. There’s a clear correlation between PCB exposure and breast cancer, and Erie County women experience higher rates of breast cancer relative to the rest of the country. Extracellular vesicles (EVs) are small particles released from cells, carrying cargo that contains lipids, proteins, and nucleic acids. EVs released from cancerous cells contain aberrantly expressed proteins and nucleic acids, reflective of the cell they were derived from and these EVs can be taken up by other cells and induce their transformation into cancerous phenotypes. If PCB exposure alters gene expression in healthy cells, and in their released EVs, this could result in the onset and spread of breast cancer. Using NIH3T3 and MCF7 cell lines we have isolated and characterized extracellular vesicles to examine the proteins and changes in gene expression. EVs were isolated from conditioned cell culture media from both cell lines under control, positive control, and PCB treated conditions. Western blotting was used to examine the expression of proteins CD63, CD81, CD9 and then RNA was isolated to assess changes in gene expression using RT-qPCR. This research will help localize gene changes in breast cancer and a causative relationship between PCB exposure and breast cancer will put more emphasis on research funding and concern for women consuming game fish in Erie County.