%0 Journal Article %T Magnetic Fluid Hyperthermia of Rodent Tumors Using Manganese Perovskite Nanoparticles %A Larissa Bubnovskaya %A Anatolij Belous %A Sergej Solopan %A Antonina Kovelskaya %A Lyudmila Bovkun %A Alexander Podoltsev %A Igor Kondtratenko %A Sergej Osinsky %J Journal of Nanoparticles %D 2014 %I Hindawi Publishing Corporation %R 10.1155/2014/278761 %X Purpose. To test the antitumor activity of magnetic fluid (MF) on the basis of substituted lanthanum-strontium manganite nanoparticles combined with alternating magnetic field (AMF) in experiments with transplanted tumors. Materials and Methods. MF with a size of nanoparticles of 30¨C40£¿nm in aqueous agarose solution was investigated. The ability of MF to heat tumor under AMF (300£¿kHz, 7.7£¿kA/m) was tested in vivo with rodent tumors (Guerin carcinoma, Walker-256 carcinosarcoma, and Lewis lung carcinoma (3LL)). Results. Single administration of MF into the tumor at a dose of 150£¿mg/kg (rats) or 200£¿mg/kg (mice) followed by AMF within 20¨C30£¿min (treatment was repeated 3-4-fold) has resulted in the complete regression of tumor in the 35% of rats and 57% of mice. Administration of MF alone or action of AMF alone has not resulted in tumor growth inhibition. The chemomodifying effect of nanohyperthermia was determined, in particular for cisplatinum: thermal enhancement ratio was 2.0. It was also observed that nanohyperthermia has resulted in the absence of 3LL metastases in 43% of mice. Conclusions. MF on the basis of lanthanum-strontium manganite may be considered as an effective inductor of tumor local hyperthermia. 1. Introduction The hyperthermia (HT) of human malignant tumor is used in the combined antitumor therapy and demonstrates significant modifying effect that results in the improvement of patients¡¯ survival [1¨C3]. At the same time technical problems of microwave HT, that is, a main method for tumor heating, do not allow receiving the maximal homogenous heating of tumor and cause the definite side effects. One of the approaches to resolve this problem is a creation of magnetic fluids (MF) on the basis of ferromagnetic nanoparticles which are able to heat the tumor tissue under external alternating magnetic field (AMF), that was shown in the pioneer work of Jordan et al. [4]. The use of nanosized magnetic particles, which are able to generate heat under AMF, offers much extensive scope for the use of HT in the therapy of malignant tumors [5¨C7]. The effective application of magnetic nanoparticles was shown in the combination with AMF in the experiment with transplanted tumors both in the regime of thermal ablation and thermochemotherapy [8, 9]. The nanoparticles of ferromagnetic materials have to meet various requirements; in particular, they must be slightly agglomerated, small sized, single-domained, easily excretable from the body, able to demonstrate high values of the SLP (specific loss power), and able to exhibit superparamagnetic properties %U http://www.hindawi.com/journals/jnp/2014/278761/