TIMP1 and systemic sclerosis: As reported before, the two concentrations (2 μg/mL and 20 μg/mL) of irinotecan used were not cytotoxic on the fibroblasts and led to a global downregulation of genes involved in fibrosis in SSc patients, except for the metallopeptidase inhibitor TIMP1 gene (supplementary data Fig. 1).