A method for predicting a subjects response to a TUSC2 therapy is provided. In particular, a subjects response is predicted based on the proportion of cancers cells that are apoptotic. Also provided is a method of treating a subject previously predicted to have a favorable response with a TUSC2 therapy. Methods for treating cancer by administration of a TUSC2 therapeutic in conjunction with an EGFR inhibitor and/or a protein kinase inhibitor are also disclosed. Kits and reagents for use in TUSC2 therapy are provided.