Testican-1-MMP axis in tumour extracellular matrix (ECM) remodelling: interaction dynamics analysis and an in silico...

The extracellular matrix (ECM) plays a pivotal role in facilitating tumour development, invasiveness, metastasis, and immunoevasive processes through dynamic ECM remodelling processes. Testican-1 (SPOCK1), an excretory matricellular proteoglycan, is suggested to exert a role in the facilitation of ECM remodelling processes through interacting with matrix metalloproteases (MMPs) and even its less known forms. The structural mechanisms of interactions between testican-1 and MMPs were studied, and their roles in tumour-promotion pathway processes were also examined using a computational approach and immunofluorescence validated by colocalisation technique analysis. A computational analysis using docking, molecular dynamics (MD), and systems biology analysis was employed. HDock and GROMACS were chosen to analyse binding affinity and testican-1 stability with 28 different MMPs. H-bond, free energy, and root mean square fluctuation (RMSF) analyses were performed to confirm the interactions in the testican-1-MMP complexes. The systems biology toolkit implemented in this study consisted of STRING, BioGRID, and Cytoscape, which were employed for testican-1 interaction network and pathway analysis. Kaplan-Meier survival analysis using the GEPIA2 tool was utilised to correlate SPOCK1 gene expression and clinical survival measures for various malignancies. The docking analysis showed robust interactions between testican-1 and MMP23, MMP25, and MMP28. Additionally, testican-1-MMP complexes were confirmed to form stable interfaces based on comprehensive MD analysis, suggesting solid binding interfaces with the MMP-unique domain of testican-1. Our systems biology experiment indicated testican-1 as a central hub for interactions between immunoevasive and ECM remodelling processes. SPOCK expression was also shown to correlate with significant survival measures for different malignancies, revealing clinical implications in cancer. The testican-1-MMP computational analysis suggests testican-1 plays a pivotal role as a therapeutic target for a wide range of malignancies. SPOCK-MMP interactions could be targeted to interrupt tumour-promoting processes by arresting dynamic changes in the ECM, thereby improving patient survival. © 2026 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.