The potential of multi-compound nanoparticles to bypass drug resistance in cancer

Purpose: The therapeutic efficacy of conventional chemotherapy against several solid tumors is generally limited and this is often due to the development of resistance or poor delivery of the drugs to the tumor. Mechanisms of resistance may vary between cancer types. However, with current development of genetic analyses, imaging, and novel delivery systems, we may be able to characterize and bypass resistance, e.g., by inhibition of the right target at the tumor site. Therefore, combined drug treatments, where one drug will revert or obstruct the development of resistance and the other will concurrently kill the cancer cell, are rational solutions. However, drug exposure of one drug will defer greatly from the other due to their physicochemical properties. In this sense, multi-compound nanoparticles are an excellent modality to equalize drug exposure, i.e., one common physicochemical profile. In this review, we will discuss novel approaches that employ nanoparticle technology that addresses specific mechanisms of resistance in cancer. Methods: The PubMed literature was consulted and reviewed. Results: Nanoparticle technology is emerging as a dexterous solution that may address several forms of resistance in cancer. For instance, we discuss advances that address mechanisms of resistance with multi-compound nanoparticles which co-deliver chemotherapeutics with an anti-resistance agent. Promising anti-resistance agents are (1) targeted in vivo gene silencing methods aimed to disrupt key resistance gene expression or (2) protein kinase inhibitors to disrupt key resistance pathways or (3) efflux pumps inhibitors to limit drug cellular efflux.