Mechanistically, the emerging picture from the study of neoplastic tumours generated in imaginal epithelial tissues (such as with mutants in the neoplastic tumour-suppressor gene (nTSG), scrib), is that tumour development occurs through the cooperative interaction of factors produced from surrounding epithelial cells or hemocytes and feed-forward mechanisms within the tumour cell amplifying this loop (Figure 2). Here, SCRIB is linked to neoplasm.