A “redox state marker” on the ferric low spin heme in may be regarded to become amode, vibrations of methineferric low spin heme in cyt c, assignedthe the v19 “redox state marker” in the bridges (CC, CCH bonds) and to CC bond v19 mode, vibrations of methineshow that human breast bonds) plus the CC bond. Our results bridges (CC CC N-type calcium channel Species cancer and brain tumor demonstrate a Our results show that human breast cancer and brain tumor demonstrate a redox imbalance in comparison to normal tissues. We identified that concentration of cytochrom imbalance compared to regular tissues. We identified that concentration ofof the 1584 cmis Raman upregulated in brain and breast cancers. The intensities -cytochrome c -1 1 upregulated in brain and breastthe quantity of intensities of cytochrome c increases signal corresponding to cancers. The the lowered the 1584 cm Raman with increasin corresponding to the quantity of the decreased cytochrome c increases with growing cancer cer aggressiveness. It indicates that cytochrome c plays a critical role in the create aggressiveness. It indicates that cytochrome c plays a critical role within the improvement and progression of cancer. We located the dependence with the Raman biomarker ICancers 2021, 13,18 ofand progression of cancer. We discovered the dependence from the Raman biomarker I1584 from the reduced cytochrome c vs grade of cancer malignancy which shows that the optimal concentration of cytochrome c which 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. The concentrations on the reduced cytochrome c at this level modulate protective, signaling-response pathways, resulting in positive effects on life-history traits. The decreased cytochrome c level above these values triggers a toxic α2β1 Compound runaway procedure and aggressive cancer development. The relation between the Raman signal intensity at 1584 cm-1 on the reduced cytochrome c vs cancer grade supplies a crucial cell-physiologic response demonstrating that the decreased cytochrome c operates at low, basal level in normal cells, however it is strongly induced to extremely high levels in pathological cancer states. We discovered that also the Raman intensity on the mixed vibrations of cytochromes c and b (750 and 1126 cm-1 ) improve with aggressiveness. The Raman peaks at 1337 cm-1 corresponding to cytochromes b does not practically change with breast and brain cancer aggressiveness. We analyzed the Raman intensity ratio on the peaks at 750 cm-1 and 1126 cm-1 to evaluate the relative contribution of cytochrome c and b in human breast tissue as a function of breast cancer grade malignancy G0-G3 at excitation 532 nm. We identified that the relative contribution of cytochrome c is larger than cytochrome b when the grade of malignancy increases.Author Contributions: Conceptualization: H.A.; Funding acquisition: H.A.; Investigation: B.B.P., M.K., J.S., M.B., M.R.; Methodology: H.A., B.B.-P., M.K., J.S.; Writing–original draft: H.A.; Manuscript editing: H.A., B.B.-P., M.K., J.S. All authors have study and agreed for the published version in the manuscript. Funding: This operate was supported by the National Science Centre of Poland (Narodowe Centrum Nauki, UMO-2019/33/B/ST4/01961). Institutional Evaluation Board Statement: The study was performed based on the guidelines of the Declaration of Helsinki, and approved by the nearby Bioethical Committee in the Polish Mother’s Memorial Hospital Analysis Institute in Lodz (53/216.