We found the dependence of the Raman biomarker I1584 of the reduced cytochrome c vs grade of cancer malignancy which shows that the optimal concentration of cytochrome c that are needed to maintain cellular homeostasis corresponds to the normalized Raman intensity of 0.006 ± 0.003 for the breast tissue and 0.074 ± 0.005 for the brain tissue. This evidence concerns the gene CYCS and cancer.