Current Drug T herapy   Eugenia Dumitra Teodor 1, * , Florentina Gatea 1 , Anton Ficai 2 and Gabriel Lucian Radu 3 1 Centre of Bioanalysis, National Institute for Biological Sciences, Bucharest, Romania; 2 Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science, University POLITEHNICA of Bucharest, Bucharest, Romania; 3 Department of Analytical Chemistry and Instrumental Analysis, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, Bucharest, Romania A R T I C L E H I S T O R Y Received: September 16, 2015 Revised: November 10, 2015 Accepted: November 19, 2015 DOI: 10.2174/1389450117666160208145835 Abstract: Background: In the last years, the production and applications of nanoparticles based on iron oxides in the field of biomedicine presented a great interest due to their particular properties. Be- cause of the expansion of the pharmaceutical industry numerous new systems for drugs delivery have appeared, and those centered on magnetic nanoparticles are in a particular attention and in different promising developmental stages. Objective: In this mini review, some representative, interesting and feasible magnetic nanostructures ob- tained recently (from last 5-6 years) with possible use in antitumor/anticancer therapy are presented. Results: The synthesis of these nanostructures with magnetic properties implies very simple assembling procedures and presents one of the lowest cytotoxic profiles. Magnetic nanostructures displayed possible appliance in a large diversity of biotechnological and medical fields, both for diagnose and therapy. Conclusion: Different types of magnetic nano-carriers loaded with different antitumor/anticancer agents and the cases tested in vivo are considered. Keywords: Functionalized magnetic nanostructures, anticancer therapy, drug delivery, combined drug release, imaging and hyperthermia. 1. INTRODUCTION In the last 10 years, many aspects about nanotechnologies had a great impact on the researchers, mainly, but even on administrations, industries, investors, finance organizations, and for ordinary people. Numerous studies and experiments were done; thus, to have a contribution in the field of new magnetic nanostructures with biomedical applications it is important to have a multidisciplinary approach and to have a harmonized knowledge in many domains such us physics, chemistry and biochemistry, biology, materials science, for the reason that this issue is very complex. In this context, it is important to design nanoparticle formulations with mag- netic behavior, appropriate sizes and charging for penetrate cells/tissues and, in the perspective of clinical applications, with the capacity to avoid or cross the main biological barri- ers which disturb nanoparticles to reach their target tissue or organ [1]. For biomedical applications, nanoparticles based on iron oxides are the main widely explored because of their specific magnetic behavior and insignificant cytotoxicity. Magnetite (Fe 3 O 4 ) and maghemite (γ -Fe 2 O 3 ), are the most frequently used for synthesis of magnetic nanoparticles with biomedical *Address correspondence to this author at the Centre of Bioanalysis, Faculty Name, National Institute for Biological Sciences, Bucharest, Romania; Tel: +40 0212200900; Fax: +40 0212200900; E-mail: eu_teodor@yahoo.com applications ( in vitro and in vivo), and other magnetic nanostructures based on metal alloys (e.g. FeCo, FePt, CoPt 3 ) are used, at this time, only for applications in vitro because of their high toxicity toward living cells [2-6]. The magnetic nanoparticles have specific physical and chemical properties which make them applicable for different objec- tives as well as magnetic resonance imaging and hyper- thermia, drug delivery, cell targeting, cell labelling and bio separation [1, 7-11]. For all mentioned purposes, high magnetic saturation and appropriate surface functionaliza- tion of nanoparticles are required; in addition, high bio- compatibility is necessary [12]. In recent years, the design and application of new nano- sized carrier systems provoked emergent attention in nanotechnologies area [13, 14]. The nanostructures are tar- geted to deliver different substances in a passive or in an active way. For tumor tissues passive targeted drug delivery can be used because of the reduced lymphatic systems of tumor tissues and their permeable vasculature with pore di- mensions ranging between 100 and 780 nm [15, 16]. These features allow what is called the “enhanced permeability and retention” effect, which permits greater accumulation of de- livered nanoparticles at the solid tumor site. On the other hand, for active targeted drug delivery is necessary a compli- cated system which implies a covalent conjugation of target- ing molecules on the nanoparticle surface, molecule which can identify and can link to particular ligands specifically expressed in cancer cells [17, 18]. 1873-5592/18 $58.00+.00 © 2018 Bentham Science Publishers Send Orders for Reprints to reprints@benthamscience.ae Current Drug Targets, 2018, 19, 239-247 239 REVIEW ARTICLE Functionalized Magnetic Nanostructures for Anticancer Therapy