We have performed our study on a NEN-treated RB cell culture derived from a real clinical autopsy material. 3.5-year-old male donor has died of a massive complex abdominal trauma being previously RB-diagnosed with NMR and ultrasound tests, tumor located behind the eye globe equator line. This is a first report ever on magnetic isotope effects of metal ions to cause the clear anti-cancer consequences in retinoblastoma cells by depriving them of the DNA repair capabilities. Both molecular mechanism of phenomenon and its possible meaning for retinoblastoma chemotherapy are presented here.