OPA1 and chronic myelogenous leukemia, BCR-ABL1 positive: Increased respiration, superoxide level and fusion-fission rate (increased OPA1 and DRP1 production) are also shown in K562 (chronic myelogenous leukemia) cells by Ruiz et al. The authors assume that increased mitochondrial turnover can lead to smaller, condensed and “boosted” mitochondria resulting in increased cell proliferation41.