Advances in nanotechnology opened up new horizons in the field of cancer research. Nanoparticles made of various organic and inorganic materials and with different optical, magnetic and physical characteristics have the potential to revolutionize the way we diagnose, treat and follow-up cancers. Importantly, designs that might allow tumor-specific targeting and lesser side effects may be produced. Nanoparticles may be tailored to carry conventional chemotherapeutics or new generation organic drugs. Currently, most of the drugs that are commonly used, are small chemical molecules targeting disease-related enzymes. Recent progress in RNA interference technologies showed that, even proteins that are considered to be "undruggable" by small chemical molecules, might be targeted by small RNAs for the purpose of curing diseases, including cancer. In fact, small RNAs such as siRNAs, shRNAs and miRNAs can drastically change cellular levels of almost any given disease-associated protein or protein group, resulting in a therapeutic effect. Gene therapy attempts were failing mainly due to delivery viral vector-related side effects. Biocompatible, non-toxic and efficient nanoparticle carriers raise new hopes for the gene therapy of cancer. In this review article, we discuss new advances in nucleic acid and especially RNA carrier nanoparticles, and summarize recent progress about their use in cancer therapy.

The importance of high transfection efficiency has been emphasized in many studies investigating methods to improve gene delivery. Accordingly, non-viral transfection agents are widely used as transfection vectors to condense oligonucleotides, DNA, RNA, siRNA, deliver into the cell, and release the cargo. Polyethyleneimine (PEI) is one of the most popular non-viral transfection agents. However, the challenge between high transfection efficiency and toxicity of the polymers is not totally resolved. The delivery of necessary drugs and genes for patients and their transport under safe conditions require carefully designed and controlled delivery systems and constitute a critical stage of patients' treatment. Compact systems are considered as the strongest candidate for the preparation and delivery of drugs and genes under leak free and safe conditions because of their low energy consumption, low waste disposal, parallel and fast processing capabilities, removal of human factor, high mixing capabilities, enhanced safety, and low amount of reagents. Motivated by this need in the literature, a platform for gene delivery via magnetic actuation of nanoparticles was developed in this study. The use of PEI-SPION (Super paramagnetic ironoxide nanoparticles) as transfection agents in in vitro studies was investigated with the effect of varying magnetic fields provided by a special magnetic system design, which was used as magnetic actuator offering different magnet's turn speeds and directions in the system. Results obtained from magnetic actuator systems were compared to the experiments without actuation and significant enhancement was observed in the transfection efficacies.