Abstract A66: βarrestin2 contributes to aggressive tumor growth in African American prostate cancer cells

Abstract

Abstract Prostate cancer (PCa) is the second leading cause of death in African American males (AA). Studies have found the incidence of PCa to be 60% higher in AA men than their Caucasian American counterparts (CA). Poorer prognosis in AA men is exacerbated by lack of adequate access to healthcare and non financial factors such as distrust of the healthcare system. However, these social and socioeconomic factors fail to fully account for this disparity. AA men are diagnosed at younger ages and often present with more advanced tumor stages and higher Gleason scores. Thus, elucidating possible biological causes of prostate cancer disparity is of utmost importance. βarrestin2 (βarr2) is a scaffold protein that associates with G protein coupled receptors (GPCRs) and leads to the desensitization and internalization of these receptors. In addition, more recent studies have implicated βarr2 in a variety of cellular processes including androgen metabolism. We have shown increased βarrestin2 expression in prostate cell lines from AA men (MDA PCa 2B) when compared to those from CA men (LNCap). Furthermore, overexpression of βarr2 in LNCap cells or knockdown of βarr2 in MDA PCa 2B cells was sufficient to alter the growth properties of these cells. These results were seen both in vitro and in vivo. Thus preliminary data indicates that βarr2 may contribute to differences between tumor growth in our model system. Further studies are needed to ascertain the cause and mechanism of βarr2 overexpression in AA men, as well as the clinical significance of these findings. Citation Information: Cancer Epidemiol Biomarkers Prev 2011;20(10 Suppl):A66.