Fudan University Cancer Center Disruption of the Basement Membrane a dense meshwork underlying the epithelial cells consisting of collagen, glycoproteins, and proteoglycans Physical barrier between epithelial cells and the stroma. Degradation of basement membrane collagen is an early and critical invasion event for epithelial cell invasion. 复旦大学上海医学院肿瘤学系复旦大学上海医学院肿瘤学系 Fudan University Cancer Center Disruption of the Basement Membrane • A dense meshwork underlying the epithelial cells consisting of collagen, glycoproteins, and proteoglycans. • Physical barrier between epithelial cells and the stroma. • Degradation of basement membrane collagen is an early and critical invasion event for epithelial cell invasion