Spectroscopic Biomarkers For Breast Tumor Grading

摘要

Breast tumors are routinely graded according to differentiation levels in clinics. However, its application is limited because the method is invasive and not quantitative. Clinically 30%- 60% of breast tumors are graded as moderately differentiated (grade 2) which is not informative for decision making. Our hypothesis is that the number of cancer stem cells (CSCs) in a breast tumor can be used as an indicator for its aggressiveness. Our hypothesis is supported by increasing evidence reported in literature. Firstly, a recent study showed that poorly differentiated tumors are enriched with cells sharing characteristic with embryonic stem cells. Independent studies also indicated that tumors characterized by aggressiveness feature may encompass a higher percentage of stem-like cancer cells than the less aggressive counterparts. Moreover, expression levels of biomarker genes for stem- like cancer cells have been observed to be reverse correlated with prognosis clinically. Based on the hypothesis, we aim to develop a novel magnetic resonance spectroscopy (MRS) based approach to assess the aggressiveness of breast tumors, by identifying characteristic nuclear magnetic resonance signal for breast CSCs and using it to quantify the number of CSCs in breast tumor.