TWIST1 and neoplasm: To investigate other mechanisms promoting EMT, a panel of transcription factors involved in EMT including zeb-1, zeb-2, snail, and twist were examined in tumor and stromal cells from dissociated subcutaneous tumors depleted of CD45, with the expression of zeb-1, zeb-2, and snail found increased in Rip2-deficient compared to wild-type tumor bearing mice, and increased expression of twist approaching statistical significance (Fig 6C).