Snail1 is a transcriptional factor that mediates EMT, and overexpression of Snail1 can induce EMT in several tumor types.27, 28, 29 Therefore, we hypothesized that zidovudine-dependent downregulation of Snail1 expression in gemcitabine-resistant pancreatic cancer cells is one of the mechanisms used to suppress the EMT-like phenotype and resensitize cells to gemcitabine. The gene discussed is SNAI1; the disease is neoplasm.