The extracellular matrix in colorectal cancer and its metastatic settling – Alterations and biological implications

Colorectal cancer (CRC) remains one of the most common cancers worldwide. Metastatic disease is ultimately fatal when incurable. Cancer research has evolved to take the importance of the tumour microenvironment (TME) into account. The extracellular matrix (ECM) has been viewed merely as a structural scaffold, but it is now evident that the ECM is a highly active part of the TME and affects tumour cell behaviour and metastatic capability. The ECM context and composition are linked to patient outcome and the response to surgical and oncological therapy in CRC patients and may be an area for developing novel biomarkers and targeted therapy. In this review we focus on the components of the ECM in human primary and metastatic CRC. We discuss future aspects of the ECM for targeted therapy, as a source of novel biomarkers, current knowledge of the area and important considerations when studying the ECM in human CRC. •Tumour microenvironment is involved in colorectal cancer progression and metastasis.•Common localisations of colorectal cancer metastases are the liver, lungs and peritoneum.•The extracellular matrix changes in structure, composition and amount in colorectal cancer.•Tumour cells affect stromal cells to secrete extracellular matrix molecules, such as collagens.•Extracellular matrix traits in metastatic colorectal cancer are potential therapeutic targets.