The present invention provides targeted nanoplex molecules which carry multimodality imaging reporters together with target enzyme inhibitors such as siRNAs and target prodrug enzymes, that are useful for theranostic imaging of cells and diseases, including, for example, various cancers, and including metastatic prostate cancer. The nanoplex molecules of the present invention provide a platform technology toward many cancer subtypes and alternative therapeutic targets. Downregulation of specific pathways using targeted enzyme inhibitors further provides unique opportunities to target cancer cells selectively while sparing normal tissue. The nanoplex molecule platform described herein has the ability to deliver multiple siRNA enzyme inhibitors. Methods of diagnosis and treatment of various diseases are also included. The strategy described herein can be useful to down-regulate multi-drug resistance pathways, or repair enzymes with the goal of increasing the efficacy, safety, and efficiency of chemotherapeutic or irradiation therapies.
