BackgroundCancer is one of the most common causes of human deaths worldwide. Nanotechnology has the potential to facilitate the detection, diagnosis, and treatment of cancer cases. Successful delivery of nucleic acids into cancer cells with the use of nanoparticles would be a significant improvement for medical and cellular biology. The use of nanoparticle-based vehicles in clinical treatment is considerably important for treating genetic disorders. Gold nanoparticles (AuNPs) have been suggested as therapeutic delivery tools for cancer. Because microRNAs (miRNAs), which induce post-transcriptional gene silencing, are deregulated in cancer cells, they are also considered as strong candidates for cancer therapy applications. In prostate and breast cancer, miR-145, a well-known tumor suppressor miRNA, is strongly downregulated in tumor tissues compared to their corresponding normal tissues.