The study described in this book presents the effects of erythropoietin on Telomerase activity and regulation in malignant and non- malignant non-erythroid cells. Erythropoietins exposure upregulates telomerase activity in a post translational level by the Lyn/SRC AKT axis. Inhibition of telomerase that shortens telomeres abolished that effect, suggesting that erythropoietins treatment might be given with anti- telomerase compounds to minimize the upregulation of telomerase in the cancer cells.