RADIOSENSITIZATION OF HUMAN MELANOMA CELLS BY SUPERPARAMAGNETIC IRON OXIDE NANOPARTICLES

GRISSI, CECILIA; MARISA L. TAVERNA PORRO; PERONA, MARINA; MORENO, SERGIO; SACANELL, JOAQUIN; DEL GROSSO, MARIELA; IBAÑEZ, IRENE; DURAN, HEBE

Congreso; Reunion anual de biociencias 2021; 2021

Melanoma is the deadliest form of skin cancer, highly metastatic and resistant totherapies. Superparamagnetic iron oxide nanoparticles (SPIONs) have shown greatpotential for diagnosis and therapy. The aim of this study was to evaluate theradiosensitizing effect of SPIONs in A375 human melanoma cells.SPIONs were synthesized and stabilized by methyl-poly(ethylene glycol). After that, itwas physicochemically characterized by transmission electron microscopy, X-raydiffraction, magnetometry and tested in vitro. Superparamagnetic behavior and lowdispersion in shape and sizes (8-17 nm) were obtained. No cytotoxicity was found inA375 cells exposed up to 250 µg/ml for 24 h. Dichloro-dihydro-fluorescein diacetateassay revealed higher reactive oxygen species levels in treated cells (p<0.05). Survivalcurves obtained by combined treatments of SPIONs and gamma irradiation ( 137 Cs)(SPIONs-IR) and fitted to the linear-quadratic model, demonstrated a significantincrease in radiation effect in SPIONs-IR treated cells (p<0.05), with surviving fractionat 2 Gy of 0.51 and 0.28 for IR and SPIONs-IR treated cells, respectively. IncreasedDNA damage by SPIONs-IR vs IR was observed by the detection of γH2AX foci at 30minutes post-irradiation and a decreased repair capacity was found at 24 h post-irradiation by analyzing the persistence and size increase of γH2AX foci in SPIONs-IRcompared with IR treated cells (p<0.05). In conclusion, SPIONs proved to be effectiveradiosensitizers of melanoma cells.