GHR and breast cancer: We used a non-cancerous BRL-4 cell line stably transfected with the rat GH receptor complementary DNA (cDNA), previously shown to respond to GH [26] and MCF-7 breast cancer cells which display a high proliferative but less invasive phenotype compared to UMR-106 cell line, and simvastatin has been shown to induce cell cycle arrest and apoptosis [6].