As PIAS4 depletion was found to potentiate AMPK activity towards mTORC1 (Fig. 1a) and AMPK activation can inhibit cancer cell growth, we next investigated whether PIAS4 depletion affect cancer cell growth in MDA-MB-231 breast cancer cells reported to be sensitive to AMPK activation4, 41. The gene discussed is PRKAB1; the disease is breast cancer.