Ghelli et al. demonstrated that osteosarcoma-derived cytoplasmic hybrids (cybrids) with common LHON mutations (11,778/ND4, 3,460/ND1, and 14,484/ND6) undergo apoptotic cell death when under metabolic stress induced by galactose, which leads cells to rely on mitochondrial respiration for ATP production (26). Here, MT-ND4 is linked to osteosarcoma.