Room: Karl Dean Ballroom B1
Purpose: To characterize the radiation-induced biochemical responses in normal and cancer cells spectroscopically using established lung and prostate cells.
Methods: Nine cells lines were investigated, including 4 human lung cells lines including fibroblasts (CCL186) and epithelial, squamous or adeno-squamous cancer cells (A549, CRL5928, and HTB178), 4 human prostate cells lines (two normal prostate epithelial (PCS440010 and CRL11610) and two prostate cancer (CRL2505 and DU145)) and 1 murine cell line (TRAMPC2). Cells were irradiated with 2, 5, 10, 15 and 30 Gy single fraction using a Cs-137 irradiator. A total of 1492 Raman spectra were acquired as a function of time post-radiation (24, 48 or 72 hrs). Principal component analysis (PCA) and discriminant function analysis (DFA) were used to analyze the Raman spectral features.
Results: PCA captured 95-97% of the variance in the Raman spectral features for all the cell lines. Overall, PCA/DFA analysis showed unirradiated cells were correctly classified in the range of 72-100% depending on the type of cells and the time point. All irradiated lung and prostate cells (normal or cancer) were classified with 79.0Â±13.6% accuracy. Unirradiated prostate normal cells were correctly identified in the range of 95-100% and lung fibroblast cells were correctly identified in the range of 84-100%. Unirradiated human prostate carcinoma cells and murine prostate cells were classified with an accuracy of > 88% and 93%, respectively. Unirradiated lung cancer cells were classified in the range of 72-100%. Multiple Raman bands assignable to DNA/RNA, protein and lipids showed prominent contributions in cell differentiation between unirradiated and irradiated with different doses.
Conclusion: 2 Gy is sufficient to characterize radiation-induced Raman features per PCA/DFA analysis for the majority of cell lines studied with a high degree of accuracy. Accuracy improved at the later time points, 48 and 72 hr relative to 24 hr in 4 cell lines.
Funding Support, Disclosures, and Conflict of Interest: This work is supported by JFCI CRAG internal pilot funding, Henry Ford Health System.