A Novel HER2 Protein\nIdentification Methodology in\nBreast Cancer Cells Using Raman Spectroscopy and Raman Imaging: An\nAnalytical Validation Study

Conventional assays\nsuch as immunohistochemistry (IHC) and <i>in situ</i> hybridization\n(ISH) used in clinical procedures\nfor quantification of the human epidermal growth factor receptor-2\n(HER2) status in breast cancer have many limitations. In the current\nstudy, we have used HER2 expression in a broad range of breast cancer\nphenotypes to explore the potential utility of a novel immunodetection\ntechnique using Raman spectroscopy and Raman imaging combined with\nartificial intelligence models. The correlations between the Raman\nmethod and conventional HER2 testing methodologies (IHC and ISH) have\nbeen tested. Raman measurements showed a strong linear correlation\n(<i>p</i> = 0.05, <i>R</i><sup>2</sup>=0,9816)\nwith IHC analysis in the studied breast cell lines: MCF-10A, MCF-7,\nMDA-MB-231, HTB-30 (SK-BR-3), and AU-565 represent normal, nontumorigenic\nepithelial cells, triple-positive breast carcinoma, and triple-negative\nbreast cancer cell lines. Analytic testing of Raman spectroscopy and\nRaman imaging demonstrated that this method may offer advantages over\nthe currently used diagnostic methodologies.