Nanoparticle-Based Drug Delivery in Cancer Therapy and Its Role in Overcoming Drug Resistance

Nanotechnology has become an important area of research in cancer treatment because nanoparticles can serve as effective drug delivery systems. Compared to traditional cancer drugs, nanoparticles offer several advantages: they are more stable and biocompatible, they can enter tumors more easily thanks to the enhanced permeability and retention (EPR) effect, and they allow for more precise targeting of cancer cells. A newer approach involves hybrid nanoparticles, which combine the benefits of different types of nanoparticles into one system, making drug delivery even more effective. One of the biggest challenges in cancer therapy is drug resistance, where cancer cells stop responding to treatment. This resistance can occur for several reasons—for example, cancer cells may pump drugs out of themselves (drug efflux), avoid cell death by disabling normal apoptosis pathways, or survive in low-oxygen (hypoxic) environments. Nanoparticles can be engineered to directly target these resistance mechanisms, helping to restore or enhance the effectiveness of cancer treatments. As scientists continue to uncover more ways cancer develops resistance, new nanoparticle systems are being designed to overcome these barriers. Recently, there has also been growing interest in using nanoparticles in cancer immunotherapy, which boosts the body’s own immune system to fight tumors. In this review, we look at how nanoparticles—and especially hybrid nanoparticles—are being used in chemotherapy, targeted therapy, and immunotherapy, and we explain how these systems work both to deliver drugs more effectively and to help reverse drug resistance.