Host tissues and extracellular microenvironment (ECM) (ECM)

The host tissues and extracellular microenvironment (ECM) represent the complex, non-cellular structural framework that surrounds cells within all tissues and organs, providing essential physical scaffolding and biochemical cues. This environment is composed of a diverse array of macromolecules, including fibrous proteins like collagen and elastin, as well as specialized glycoproteins and proteoglycans such as hyaluronic acid (Frantz et al., 2010, Journal of Cell Science). Beyond providing physical support, the microenvironment serves as a reservoir for growth factors and mediates essential biochemical and biomechanical signals that regulate cell survival, proliferation, and migration (Anderson & Simon, 2020, Current Biology). In various diseases, particularly cancer and chronic fibrosis, the microenvironment is pathologically remodeled, leading to increased tissue stiffness and the creation of physical barriers that impede the delivery of therapeutic agents. Drugs targeting this compartment, such as hyaluronidases or collagenases, aim to degrade these barriers to enhance the penetration of co-administered therapies or to disrupt the supportive niche of malignant cells (PubChem). However, therapeutic manipulation of the host environment carries significant risks, including the potential for unintended tissue damage or the promotion of metastasis by loosening the structural constraints on tumor cells (NIH/NCBI).

Other names

Extracellular matrixExtracellular microenvironmentInterstitial matrixTumor microenvironmentTMEHost environment

Enzymatic degradation of extracellular matrix components to reduce interstitial fluid pressure and improve drug delivery; inhibition of integrin-mediated cell adhesion; and modulation of matrix metalloproteinase activity.