To further prove the role of TGF-β2 in EMT under acidic conditions, we silenced Smad2/3 (Supplementary Fig. 5h, i) and confirmed a dramatic reduction in SNAIL1 and ZEB1 in 6.5/cancer cells (Fig. 5g, h and Supplementary Fig. 5j). The gene discussed is SMAD2; the disease is cancer.