Abstract 3805: Revealing the role of microRNAs in the emergence of cancer stem cell heterogeneity during colorectal cancer progression

Our goal is to identify microRNAs (miRNAs) that target mRNAs involved in stem cell (SC) signaling pathways involved in colorectal cancer (CRC) tumorigenesis. SC overpopulation drives CRC progression but exact mechanism is unclear. Hypothesis: specific miRNAs target SC genes, which leads to the emergence of multiple cancer SC (CSC) sub-populations and tumor heterogeneity. We used flow cytometry to identify CSC sub-populations based on expression of SC markers including ALDH1, LGR5 and others in the HT-29 CRC cell line. CSC sub-populations were isolated and measured using FACS and expression of miRNAs in each CSC sub-population was quantified using NanoString profiling. The level of miRNA upregulation in each CSC sub-population was ranked based on differential expression of the miRNAs between different CSC sub-populations. We chose to further analyze the LGR5 and ALDH SC sub-populations because they showed: i) the largest difference between CSC sub-population sizes, ii) the smallest size (