Chemoselective Characterization of New Extracellular Matrix Deposition in Bioengineered Tumor Tissues

Investigating ECM-regulated new ECM production has been challenging due to the proteomic background from the pre-existing biomaterial ECM. To address this issue the newly synthesized ECM proteins (newsECM) of two different bioengineered tumor models were analyzed: tumor tissues, built upon decellularized ECM (dECM-tumors) or as ECM-free tumor spheroids (tumoroids). newsECM proteins were labeled and enriched using a chemoselective strategy, employing a click-chemistry compatible, azido tag bearing monosaccharide probe, azido-galactosamine tetra-acetylated (Ac4GalNAz). The newsECM profiles within the two tumor models were characterized and compared by means of LC-MS/MS and subsequent follow up data analysis.