As a transcriptional kinase for RNA polymerase II, sustains the expression of multiple resistance-associated kinases and proliferative genes. In HER2-resistant breast cancer models, CDK7 inhibitors disrupt HER2/PI3K/AKT-driven kinase reprogramming, synergize with HER2 inhibitors, and effectively reverse resistance. Here, AKT1 is linked to breast carcinoma.