Plays a role as a transcription factor (PubMed:22132193, PubMed:25355627). Mediates positive transcriptional regulation of several chaperone genes during the heat shock response in a HSF1-dependent manner (PubMed:25355627, PubMed:25816751). Mediates negative transcriptional regulation of CDC25B expression (PubMed:22132193). Plays a role in the dephosphorylation of the heat shock factor HSF1 and ribosomal protein S6 kinase (S6K) by the protein phosphatase PP2A (PubMed:25816751, PubMed:26496226). Involved in the regulation of cell proliferation and resistance to thermal stress (PubMed:22132193, PubMed:25355627, PubMed:26496226). Involved in the cell cycle checkpoint and survival in response to ionizing radiation (PubMed:19238419, PubMed:22132193). Associates with chromatin to the CDC25B promoter (PubMed:22132193). Monomer (PubMed:26496226). Homodimer (PubMed:26496226). Associates with the catalytic subunit of protein phosphatase PP2A (PubMed:25816751, PubMed:26496226). Interacts (via N- and C-terminal regions) with PPP2R2B (PubMed:25816751, PubMed:26496226). Interacts with PPP2R2A, PPP2R2C and PPP2R2D (PubMed:25816751). Interacts (via N-terminus) with RPS6KB1 (PubMed:26496226). Interacts (via central region) with HSF1; this interaction promotes PPP2CA-induced HSF1 dephosphorylation, leading to enhanced HSF1 transcriptional activity (PubMed:25816751, PubMed:26496226, PubMed:26754925). Predominantly cytoplasmic (PubMed:25816751). Translocated in the nucleus during heat shock (PubMed:25816751). Expressed in acute myeloid leukemia (AML) cells. Up-regulated by heat shock in a heat shock HSF1-dependent manner (PubMed:25355627). Up-regulated by ionizing radiation (PubMed:19238419). Belongs to the IER family.