In a contrasting analysis, Liu et al. proposed that UCHL1 promotes breast cancer metastasises by deubiquitinating and stabilising TGFβR1 and SMAD2 in TNBC by maintaining the TGF-β signalling pathway [54], with UCHL1 inhibition using a cyanpyrrolidine-based covalent inhibitor 6RK73 or genetic knockdown antagonising TGF-β signalling in TNBC models. This evidence concerns the gene SMAD2 and breast carcinoma.