With the advent of the theranostics era in biomedical research, gene therapy is poised to offer more, provided that more efficient delivery vehicles are discovered and developed. Chitosan is a biomatrix that is abundant, biocompatible, biodegradable, versatile, inexpensive and safe. These features have paved the way for its use in gene therapy, mainly for delivery of therapeutic plasmids and more recently for siRNA. Recent studies show that chitosan per se exhibits anticancer properties both in vitro and in animal models, most probably through the p21/Cip and p27/Kip pathways. This review looks at the in vivo studies using chitosan technology towards cancer gene therapy, drawing some support from non-cancer studies. The future of this promising technology lies in the evolution of new ideas for enhanced nucleic acid drug pharmacokinetics and, consequently, pharmacodynamics for cancer patients.