COL1A1 and systemic sclerosis: Although incubation with 20 μg/mL irinotecan during 24 h decreased mRNA expression of COL1A1 (− 27 ± 13.25), COL1A2 (− 20.5 ± 9) and CCL2 (− 15 ± 9.4) in dermal fibroblasts of SSc patients treated with irinotecan vs. the non-treated condition, these differences were not statistically significant (Fig. 3).