Study on the Molecular Mechanisms Against Human Breast Cancer from Insight of Elemental Distribution in Tissue Based on Laser-Induced Breakdown Spectroscopy (LIBS).

The role of elements in physiological and pathological metabolic processes remains an unmet challenge in biomedical research and clinical applications. Herein, a visual elemental imaging of tumor tissue platform of a laser-induced breakdown spectroscopy (LIBS) was developed to initially understand anti-tumor mechanisms. The relative enrichment degree and heterogeneous spatial distributions of four elements (calcium, sodium, copper, and magnesium) of tumor tissue from different treated could be easy to visualize. In particular, significant differences in the distribution of elements were observed in tumor tissue from drug-loading complex (hydrogel/DOX) treatment group. Correspondingly, the analysis of histopathological morphology showed that the morphology and density of tumor tissue in hydrogel/DOX treatment group changed obviously by using hematoxylin and eosin (H&E) staining assay, meanwhile cleaved caspase-3 (caspase-3) and tumor necrosis factor (TNF-α) were expressed at high levels tumors tissue in hydrogel/DOX treatment group by using immunohistochemical (IHC) staining. These results would endow different biological elements with incredible potential to study the mechanisms of anti-tumor, which opens new direction and perspectives for the multi-elemental mapping of biological tissues, especially in clinic application. The integrated platform of DNA nanohydrogel drug carrier-based anti-tumor treatment combined with LIBS elemental imaging, via tail intravenous injection of saline, hydrogel, DOX, and hydrogel/DOX in breast cancer xenograft tumor mice. (A) The workflow is outlined starting from nanohydrogel drug carrier-based anti-tumor treatment. (B) Schematic diagram of LIBS imaging platform.