Study of the relationship among biomarkers, cell and tissue of glioma through Raman spectroscopy

Abstract

Glioma is the most common brain tumors with high mortality and recurrence rates. Currently, the diagnosis methods for glioma are mainly based on tissue level, cell level and biomarker level. In this paper, the characteristics of biomarkers (γ-aminobutyric acid and matrix mtalloproteinses-2), U87MG glioma cell and tissue were studied based on Raman spectroscopy, respectively. The results showed that the γ-aminobutyric acid concentration exhibited a linear relation with the intensity of characteristic peaks in 800–1600 cm−1 region, whereas the spectral baseline increased with the increasing of sample concentration in 200–700 cm−1 region. The Raman characteristics of matrix mtalloproteinses-2 in 20–1800 cm−1 region was investigated. Especially, it is demonstrated that the matrix mtalloproteinses-2 showed sixteen low-wavenumber Raman peaks in the range of 20–300 cm−1. Moreover, the U87MG glioma cell showed seven different Raman characteristic peaks in 600–1800 cm−1 region. Compared with the normal tissue, the Raman intensity of tumor tissue showed apparent intensity differences in 300–1800 cm−1, where the intensity changes of these Raman peaks were related to the reducing of the lipid metabolic pathways, and increase of the RNA in tumor tissue region. Furthermore, it is found that the Raman spectra of U87MG glioma cell and tumor tissue had corresponding peaks in the Raman spectra of the liquid γ-aminobutyric acid and matrix mtalloproteinses-2. It is suggested that the γ-aminobutyric acid and matrix mtalloproteinses-2 contributed to the formation and growth of glioma cell and tissue. Thus, Raman spectroscopy not only can diagnose glioma at the biomarkers, cellular and tissue level, but also analyze the relationship among the three. Furthermore, the results provided a physical marker for the detection of glioma in clinically