SMAD3 and systemic sclerosis: Among the 87 genes we tested, it is noteworthy that the shRNAs targeting the SMAD family were not identified as the strongest regulators of the ASMA expression in SSc dermal fibroblasts: 1 SMAD2 shRNA led to more than 35% inhibition of ASMA expression; 1 SMAD3 shRNA and 2 SMAD4 shRNAs led to more than 25%, but less than 35% inhibition of ASMA expression.