Figure 2

Schematic overview of possible sequelae of oncoprotein metastasis (OPM) and a potential OPM treatment with distinct antineoplastic peptides. a) Morphological sequelae of OPM and its (epi)genetic correlates ultimately making a seemingly normal cell adopt a malignant appearance ("morphological switch"). b) Molecular sequelae of OPM resulting in a tumor suppressor protein (TSP) loss of function (after a reactive or compensatory upsurge in response to the initial oncoprotein challenge) already at an early stage of the oncogenic process when the affected cells have still a (deceivingly) normal appearance ("functional switch"). c) Antagonism of OPM by treatment (Rx) with TSP-like peptides featuring a binary structure that combines an antiproliferative (AP) segment with a nuclear localization sequence (NLS) the latter of which also mediates cellular penetration/internalization and thus ensures that these antineoplastic peptides are able to enter and influence both (premalignant) normal-appearing cells and cancer cells. For a more complete picture, it should be added that non-peptide mimetics of these peptides are also conceivable (albeit, for specific reasons to be discussed elsewhere, not preferred) therapeutics. Moreover, chemopreventive (peptide and non-peptide) agents are likely to achieve their beneficial effects by a similarly global internalization into non-malignant and premalignant cells.