Extracellular Matrices

The extracellular matrix (ECM) protein is a complex network of macromolecules comprised of proteoglycans and fibrous proteins. The composition is tissue specific and plays a critical role in modulating cellular functions.

Key proteins in ECM architecture: Collagen, Elastins, Fibronectins, Laminins

Pre-Metastatic Niche and ECM
Pre-metastatic niche is a local micro-environment in a tumor that favors attachment, survival and growth of circulating tumor cells (CTCs) leading to abnormal tumor growth. Studies have shown the involvement of a multitude of soluble factors and cells that secrete them. These include growth factors secreted by tumor cells, immune cells, extracellular vesicles and bone-marrow derived stromal and non-stromal cells. The pro-inflammatory factors secreted by these cells induce the expression of chemoattractant such as S100 proteins that promote cell proliferation and inhibit apoptosis, thus creating an environment that favors metastasis. In addition, tumor-secreted exosomes that express a range of integrin subtype on their membrane are selectively taken up by distant non-tumor cells in a tissue specific manner, thus initiating the formation of pre-metastatic nice.

Key proteins involved in pre-metastatic niche formation

References:

1. Extracellular Matrix Alterations in Metastatic Processes, Paolillo and Schinelli, Int. J. Mol. Sci. 2019,4947
2. Extracellular Matrix: The Gatekeeper of tumor angiogenesis, Monigiat et al, Biochem Soc Trans. 2019, Oct, 13,; 47(5)