Confocal Raman Microscope for the study of anti-cancer drug delivery by dental pulp stem cells
Résumé
Using stem cells as anticancer drug carriers aims for targeting tumors and reducing the side effects of chemotherapy. Coupling the multipotential capacities of stem cells with the nanomedical properties of the drugs provides an attractive platform for cancer therapy. Raman microscopy with its high spatial resolution and sensitivity is used as a unique tool to trace drugs and cellular components without labeling. Drug uptake, transfer, and release by stem cells, in addition to the effect on tumor cells were studied by Confocal Raman Microscope.
Moreover, to further understand the intra-cellular effect of paclitaxel drug exposure and stem cell treatment upon the stem and cancer cells, we have traced different enzymes and biomarkers intra-cellularly. By software-aided Raman analysis, we were able to detect and measure the enzymes: cytochrome c in the mitochondria and Matrix Metalloproteinase MMP-1, as cellular markers pre and post-treatment. This was performed by calculating the Pearson correlation coefficient for the selected reference spectrum to the spectral correlation matrix. We investigated the cellular viability by means of confocal Raman microscope, also verified by apoptosis and cytotoxic assays.
Our results prove the promising use of dental pulp stem cells as cellular vehicles, and significant phenotypic change in cellular marker expression after treatment with paclitaxel. Biochemical imaging of intracellular drug uptake using Confocal Raman would help to have a better understanding of drugs mechanism of action and cellular behavior, including cellular interaction mechanisms.