HIPK1 phosphorylates CREB and activates C/EBPβ in cardiomyocytes. a) NRCMs were treated with PE, and HIPK1 expression was evaluated by Western blot in the cytoplasm and nucleus components, respectively (n = 3). b) Western blot for CREB phosphorylation and C/EBPβ isoform expression in the nucleus component of NRCMs treated with PE (n = 3). c) H9C2 cell lysates were incubated with CREB antibody, and co‐immunoprecipitation of CREB and HIPK1 was evaluated by Western blot. d,e) Western blot for HIPK1, CREB phosphorylation, and C/EBPβ isoform expressions in NRCMs transfected with d) sh‐HIPK1 or e) OE‐HIPK1 lentivirus (n = 3). f,g) qRT‐PCR for HIPK1 and C/EBPβ in NRCMs transfected with f) sh‐HIPK1 (n = 5) or g) OE‐HIPK1 (n = 6) lentivirus. h) Western blot for HIPK1, CREB phosphorylation, and C/EBPβ expressions in NRCMs transfected with OE‐HIPK1, OE‐HIPK1 (K219A, kinase‐inactive mutant form of HIPK1 by changing Lysine to Alanine at position 219), and Fugw control plasmids (n = 3). Data between two groups were compared by independent‐sample two‐tailed Student's t‐test. Data among three groups were compared by one‐way ANOVA test. *, p < 0.05; **, p < 0.01; ***, p < 0.001; ns, not significant.