Disclosed are proteinaceous molecules and their use in conditions associated with PKC-θ overexpression, such as cancer. More particularly, the present invention discloses proteinaceous molecules and their use in altering at least one of (i) formation; (ii) proliferation; (iii) maintenance; (iv) epithelial to mesenchymal cell transition; or (v) mesenchymal to epithelial cell transition of a PKC-θ overexpressing cell.