Dermal fibroblasts from 10 SSc patients were treated with salirasib in the presence of TGF‐β1, and mRNA levels of H‐Ras and genes related to fibrosis, such as COL1A1, COL1A2, CTGF, TGF‐β1, fibronectin, ACTA2, and MMP1 was measured by real‐time PCR. The gene discussed is MMP1; the disease is systemic sclerosis.