Collagen changes in the extracellular matrix of tumor-affected human breast: a tale of OF/LB and type V collagens

It is widely acknowledged that the extracellular matrix (ECM) ofconnective tissues plays active roles in numerous biological processessuch as cell differentiation, life/death promotion and carcinogenesis.Ductal infiltrating carcinoma (DIC) of the breast is a highly metastatictumor histotype commonly associated with drastic massive alterations ofECM architecture and composition, especially concerning its collagenouscomponent. In particular, it was demonstrated that the stroma of DIC ofthe human breast contains a considerable amount of an embryo-foetalcollagen type (OF/LB), while type V collagen, which is a minorcomponent of normal human breast ECM, undergoes over-deposition inthe affected gland. In vitro studies indicated that substrates made fromthese collagen species were able to exert a marked and opposite effect onviability, proliferation and invasiveness of DIC-derived breast cancer celllines. In this chapter, we will summarize and discuss the studies on OF/LB and type V collagens and their putative relevance in DIC ingrowth.