Recent development of silica nanoparticles as delivery vectors for cancer imaging and therapy

In spite of significant advances in early detection and combined treatments, a number of cancers are often diagnosed at advanced stages and thereby carry a poor prognosis. Developing novel prognostic biomarkers and targeted therapies may offer alternatives for cancer diagnosis and treatment. Recent rapid development of nanomaterials, such as silica based nanoparticles (SiNPs), can just render such a promise. In this article, we attempt to summarize the recent progress of SiNPs in tumor research as a novel delivery vector. SiNP-assisted imaging techniques are used in cancer diagnosis both in vitro and in vivo. Meanwhile, SiNP-mediated drug delivery can efficiently treat tumor by carrying chemotherapeutic agents, photosensitizers, photothermal agents, siRNA, and gene therapeutic agents. Finally, SiNPs that contain at least two different functional agents may be more powerful for both tumor imaging and therapy. (C) 2014 Elsevier Inc. All rights reserved.