LGR5 positivity defines stem-like cells in colorectal cancer [aCGH]

Lgr5-EGFP-IRES-Cre-ERT2 mice were exposed to azoxymethane/dextrane sodium sulfate (AOM/DSS) which induces inflammation-driven colon tumors. Tumors were then flow-sorted into fractions of epithelial cells that expressed high or low levels of Lgr5. To exclude that transcriptional differences between Lgr5 high and low mouse colon tumor cells were imposed by distinct patterns of chromosomal aberrations in the two cell fractions, we also performed array comparative genomic hybridization (aCGH) from these tumors. All eight analyzed tumors were chromosomally stable, and thus, no difference between Lgr5 high and low cells could be detected. AOM/DSS-induced mouse colon tumors were flow-sorted into Lgr5 high and low cells before aCGH was performed. Biological replicates: 8. Two CGH array platforms.

将Lgr5-EGFP-IRES-Cre-ERT2小鼠暴露于偶氮甲烷/右旋葡聚糖硫酸钠（azoxymethane/dextrane sodium sulfate，AOM/DSS）以诱导炎症驱动型结肠肿瘤。随后通过流式细胞分选将肿瘤组织分离为Lgr5表达水平高低不同的上皮细胞组分。为排除Lgr5高低表达小鼠结肠肿瘤细胞间的转录差异由两种细胞组分的染色体畸变模式差异所介导，我们还对上述肿瘤开展了阵列比较基因组杂交（array comparative genomic hybridization，aCGH）分析。经检测，全部8个被分析的肿瘤均呈染色体稳定状态，未发现Lgr5高低表达细胞间存在染色体差异。在进行aCGH分析前，我们先通过流式分选将AOM/DSS诱导的小鼠结肠肿瘤分离为Lgr5高表达与低表达细胞群。本研究生物学重复数为8，采用了2种CGH阵列平台。