ERBB2 and triple-negative breast carcinoma: In triple-negative breast cancer, there is low expression of hormone receptors (ER and PR) and HER2 gene, increased expression of genes involved in cell cycle regulation, such as Cyclin B1 and CDC20, high expression of genes involved in DNA damage repair, such as RAD51 and BRCA1, and high expression of genes involved in immune response and inflammation, such as IFNγ and TNFα.