Under chronic stress, corticotropin-releasing factor (CRF) released by the hypothalamus has been found to promote breast cancer cell invasion and metastasis through mechanisms involving FAK phosphorylation, actin polymerization, and prostaglandin production.171 β-Adrenergic signaling activated by chronic psychological stress has been shown to not only activate prometastatic pathways within breast cancer cells but also participate in the construction of premetastatic niches. The gene discussed is PTK2; the disease is breast carcinoma.