ATF4 and clear cell renal carcinoma: It was noted that in five cancer types (breast invasive carcinoma, kidney papillary and kidney clear cell carcinomas, liver hepatocellular carcinoma and prostate adenocarcinoma), IMPACT expression inversely correlated (ρ = − 0.26 to − 0.46, P < 10− 5) with the expression of the central stress response transcription factor ATF4 [29] and its downstream target, a pro-apoptotic molecule DDIT3 (CHOP) [30] (Fig. 2a).