AR and cancer: On the signaling elicited by the androgen receptor (AR) stimulation (Fig. 1f), CK2 activity has been shown essential for the stability of the receptor protein, and therefore to support the AR transcriptional action.15,16 Some roles of CK2 have been reported also in other signaling pathways, such as Hedgehog,17 TNF-α,18 Notch1,19 and Tyr-kinase receptors.18,20 The degree by which CK2 potentiates each signal depends of course on its expression/activity level, becoming prominent in cancer cells, where CK2 is usually overexpressed3,6 (see below).