In terms of cellular ATP content, PHA inhibited the proliferation of three kinds of breast cancer cells: MCF7 (estrogen receptor (ER)+, progesterone receptor (PR)+/−, human epidermal growth factor receptor 2 (HER2)−), SKBR3 (ER−/PR−/HER2+), and MDA-MB-231 (triple-negative). The gene discussed is ERBB2; the disease is breast cancer.