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Kopec, M.

Publications and source records attributed to Kopec, M..

4 recordsLinked to original sources

Double face of cytochrome c in cancers.New look into human breast ducts with Raman imaging

Cytochrome c (Cyt c) is a key protein that is needed to maintain life (respiration) and cell death (apoptosis). The dual-function of Cyt c comes from its capability to act as mitochondrial redox carrier that transfers electrons between the membrane-embedded complexes III and IV and to serve as a cytoplasmic apoptosis-triggering agent, activating the caspase cascade.1-6 However, the precise roles of Cyt c in mitochondria, cytoplasm and extracellular matrix under normal and pathological conditions are not completely understood.7-9 To date, no pathway of Cyt c release that results in caspase activation has been compellingly demon-strated in any invertebrate.10 The significance of mitochondrial dysfunctionality has not been studied in ductal carcinoma to the best of our knowledge.1 Here we show that proper concentration of monounsaturated fatty acids, saturated fatty acids, cardi-olipin and Cyt c is critical in the correct breast ductal functioning and constitutes an important parameter to assess breast epithelial cells integrity and homeostasis. We look inside human breast ducts answering fundamental questions about location and distribution of various biochemical components inside the lumen, epithelial cells of the duct and the extracellular matrix around the cancer duct during cancer development in situ. We found in histopathologically controlled breast cancer duct that Cyt c, cardi-olipin, and palmitic acid are the main components inside the lumen of cancerous duct in situ. The pre-sented results show direct evidence that Cyt c is released to the lumen from the epithelial cells in can-cerous duct. In contrast the lumen in normal duct is empty and free of Cyt c. Our results demonstrate how Cyt c is likely to function in cancer development. We anticipate our results to be a starting point for more sophisticated in vitro and in vivo animal models. For example, the correlation between concentration of Cyt c and cancer grade could be tested in various types of cancer. Furthermore, Cyt c is a target of anti-cancer drug development 11,12 and a well-defined and quantitative Raman based assay for oxidative phosphorylation and apoptosis will be relevant for such developments.

cancer biology

Raman imaging and statistical methods for analysis various type of human brain tumor

Spectroscopic methods provide information on the spatial localization of biochemical components based on the analysis of vibrational spectra. Raman spectroscopy and Raman imaging can be used to analyze various types of human brain tissue. The objective of this study is employment of Raman spectroscopy and Raman imaging to evaluate the Raman biomarkers to distinguish tumor types. We have demonstrated that bands characteristic for carotenoids (1156 cm-1, 1520 cm-1), proteins (1004 cm-1), fatty acids (1444 cm-1, 1655 cm-1) and cytochrome (1585 cm-1) can be used as universal biomarkers to distinguish aggressiveness in human brain tumor. The sensitivity and specificity obtained from PLS-DA have been over 85%. Only for pituitary adenoma the specificity is lower and takes equal 46%. The presented results confirm the potential applications of vibrational spectroscopy methods in oncological diagnostics.

cancer biology

Revision of commonly accepted Warburg mechanism of cancer development. Redox-sensitive mitochondrial cytochromes in breast and brain cancers by Raman imaging

BackgroundWe studied oncogenic processes that characterize human breast cancer (infiltrating ductal carcinoma (IDC)) and human brain tumors: glioma, astrocytoma and medulloblastoma based on the quantification of cytochrome redox status by exploiting the resonance-enhancement effect of Raman scattering. MethodsWe used Raman imaging to monitor changes in the redox state of the mitochondrial cytochromes in ex vivo human brain and breast tissues surgically resected specimens of human tissues and in vitro human brain cells of normal astrocytes (NHA), astrocytoma (CRL-1718), glioblastoma (U87-MG) and medulloblastoma (Daoy), and human breast cells of normal cells (MCF 10A), slightly malignant cells (MCF7) and highly aggressive cells (MDA-MB-231) by means of Raman microspectroscopy at 532 nm. ResultsWe visualized localization of cytochromes by Raman imaging in the major organelles in cancer cells. We demonstrated that the "redox state Raman marker" of the ferric low spin heme in cytochrome c at 1584 cm-1 can serve as a sensitive indicator of cancer aggressiveness. We compared concentration of reduced cytochrome c and the grade of cancer aggressiveness in cancer tissues and single cells and specific organelles in cells: nucleous, mitochondrium, lipid droplets, cytoplasm, and membrane. ConclusionsWe found that the concentration of reduced cytochrome c becomes abnormally high in human brain tumors and breast cancers in human tissues. Our results suggest that the mechanisms controlling the electron transport chain are spectacularly deregulated in cancers and indicate that electron transport, organized in terms of electronegativity, is inhibited between complex III and cytochrome c for isolated cells in vitro and between cytochrome c and complex IV in brain and breast tissues. The results provide evidence that the extracellular matrix and interactions with cell microenvironment play an important role in the mechanisms controlling the electron transport chain by cytochrome c. Our results reveal the universality of Raman vibrational characteristics of mitochondrial cytochromes in metabolic regulation in cancers that arise from epithelial breast cells and brain glial cells.

cancer biology

Redox Imbalance and Biochemical Changes in Cancer by probing redox-sensitive mitochondrial cytochromes in label-free visible resonance Raman imaging

BackgroundTo monitoring redox state changes and biological mechanisms occurring in mitochondrial cytochromes in cancers improving novel methods are required. MethodsWe used Raman spectroscopy and Raman imaging to monitor changes in the redox state of the mitochondrial cytochromes in ex vivo human brain and breast tissues at 532 nm, 633 nm, 785 nm. ResultsWe identified the oncogenic processes that characterize human infiltrating ductal carcinoma (IDC) and human brain tumors: gliomas; astrocytoma and medulloblastoma based on the quantification of cytochrome redox status by exploiting the resonance-enhancement effect of Raman scattering. We visualized localization of cytochromes by Raman imaging in the breast and brain tissues and analyzed cytochrome c vibrations at 750, 1126, 1337 and 1584 cm-1 as a function of malignancy grade. We found that the concentration of reduced cytochrome c becomes abnormally high in human brain tumors and breast cancers and correlates with the grade of cancer aggressiveness. ConclusionsWe showed that Raman imaging provides additional insight into the biology of astrocytomas and breast ductal invasive cancer, which can be used for noninvasive grading, differential diagnosis, delineation of tumor extent, planning of surgery, and radiotherapy and post-treatment monitoring. Simple SummaryGliomas comprise around 30% of human brain tumors, while invasive ductal carcinoma (IDC) comprises around 80% of human breast cancers. The aim of our study was to show that cancerogenesis affects the redox status of mitochondrial cytochromes, which can be tracked by using Raman spectroscopy and imaging. We have shown the correlation between the intensity of cytochromes Raman bands at 750, 1126, 1337 and 1584 cm-1 and malignancy grade for brain and breast cancers. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=171 SRC="FIGDIR/small/409359v1_ufig1.gif" ALT="Figure 1"> View larger version (51K): org.highwire.dtl.DTLVardef@1b5ab1corg.highwire.dtl.DTLVardef@1f4df05org.highwire.dtl.DTLVardef@15dce93org.highwire.dtl.DTLVardef@1a522ee_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology