B2M and B-cell chronic lymphocytic leukemia: The rate of OXPHOS has been correlated with the degree of the disease aggressiveness: Gandhi’s group observed that CLL cells show variable respiration rates, and cells with higher rates were from patients characterized by unfavorable prognostic markers, such as a higher Rai score, beta 2 microglobulin (β2M), Zap70, and unmutated immunoglobulin heavy chain (IGHV) encoding genes [101].