Figure 2

The association between NEAT1_2 expression and HER2 status is verified in an independent breast cancer cohort and in breast cancer cell lines. (a) NEAT1_2 expression was analyzed in microarray gene expression profiling data from patients in the Oslo2 cohort and correlated to tumor grade. The Kruskal-Wallis test was used to calculate whether any groups are significantly different from each other and Wilcoxon Rank-Sum test was used in post-testing for significant differences between pairs of groups. (***p ≤ 0.0001; **p ≤ 0.01). (b) NEAT1_2 expression levels were correlated to HER2 status. The Wilcoxon Rank-Sum test was used to test for significant differences between the groups. (c) and (d) NEAT1_2 expression positively correlates with ERBB2 copy number (c) and ERBB2 mRNA expression (d) in HER2-positive, but not in HER2-negative, patients. Correlation was calculated using Spearman’s rank correlation. (e) Breast cancer cell lines were subjected to NEAT1_2 RNA-FISH and NEAT1_2-specific signal intensity per nucleus in at least 250 cells was quantitated. Data are given as mean (thick black line) ±standard deviation (thin black lines). Circles represent single cell intensities. The Kruskal-Wallis test was used to calculate whether any groups are significantly different from each other. (f) RNA was isolated from breast cancer cell lines and the expression of NEAT1_2 was determined by RT-qPCR. The geometric means of B2M, GAPDH, and RPLP0 were used for normalization. The mean value ± standard deviation of three biological independent experiments is presented as fold change relative to MCF7 NEAT1_2 expression. Statistical significance was calculated using the Kruskal-Wallis test. Data were considered statistically significant when p ≤ 0.05.