Nevertheless, it usually heterodimerizes with other HER family members, especially HER2; the most active heterodimer is the HER2/HER3 dimer, which can activate the phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) and the mitogen-activated protein kinase pathways in cancer [8–10]. The gene discussed is AKT1; the disease is cancer.