ERBB2 and plasma cell myeloma: As an oncogene, SEI1 is associated with mechanisms that lead to chromosomal instability, such as increasing chromosomes numbers, double minute chromosomes, and micronuclei formation.[24] Furthermore, SEI1 inhibits apoptosis and promotes metastasis through PI3K‐Akt or integrin‐linked kinase (ILK) modulation in HER2/neu‐positive and neu‐negative cancer cells.[32] However, the role of SEI1 in myeloma remains unclear.