Collagen and fibronectin: threads linking obesity and breast cancer

Evidence from epidemiological and clinical studies correlates obesity with an increased risk for postmenopausal breast cancer and a worse prognosis for breast cancer patients regardless of menopausal status (1). However, the cellular, molecular and structural mechanisms driving this process remain unclear. A potential structural mechanism is extracellular matrix (ECM) density, which is an independent risk factor for breast cancer (2,3). Myofibroblasts, the contractile, spindle-shaped, stress fiber-forming mesenchymal cells capable of producing copious amounts of ECM have emerged as a common hallmark of wound healing and tumor progression (4), leading to the generally held view that tumors are “wounds that do not heal”