Improving the efficacy of magnetic nanoparticle-mediated hyperthermia using trapezoidal pulsed electromagnetic fields as an in vitro anticancer treatment in uveal melanoma and glioblastoma multiforme cell lines

Magnetic hyperthermia (MHT) is a novel cancer treatment that utilizes magnetic nanoparticles (MNPs) to generate localized heat under low frequency alternating magnetic field (AMF). Recently, trapezoidal pulsed alternating magnetic fields (TPAMF) have proven their capability in enhancing the efficiency of heating in MHT as compared to the sinusoidal one.. Our study aims to compare TPAMF waveform’s killing effect against the sinusoidal waveform in B16F10 and CT2A cell cultures to determine more efficient waveforms in causing cell death. For that purpose, we used SPIONs (superparamagnetic iron oxide nanoparticles) at 1 and 4 mg/ml with four different AMF waveforms: three non-sinusoidal, namely trapezoidal (TP), almost-square (TS) and triangular (TR), and the sinusoidal signal (SN). Among the explored cases, the non- harmonic signals demonstrated better efficacy than the SN one as MHT treatment. After MHT treatments, B16F10 cells incubated with SPIONs at 1 mg/ml, reached cell death rates of 31±2% and 17±5%, when TP and TS signals were applied. Whereas cell death rates reached by SN was only 0% by both TP and TS signals. In CT2A cells preincubated with SPIONs at 4 mg/ml, MHT treatments using TP and TS signals induced a cell death rate of 46±15% and 35±16%, respectively, and the MHT treatments using SN produced 14±2% and 4±2% compared to TP and TS. Based on these results, we can conclude that the application of non-harmonic signals enhances MHT treatment efficiency against tumor cells.