Figure 2. Let-7a and let-7i levels are inversely correlated with HER2 status in breast cancer cells.
Ten nanograms of isolated miRNA from 70% confluent (A) 231 NEO and 231 HER2 or (B) MCF7, BT-474, and SKBR3 human breast cancer cells were reverse transcribed to cDNA and then analyzed by qRT-PCR for let-7a, let-7i, and U6 expression. The figures are representative from (A, B) one of two independent experiments performed in triplicate. A t-test or one-way ANOVA test was performed. (C) Western blot analysis of HER2, PARP1, PARP2 and β-actin levels in untreated 231 NEO, 231 HER2, MCF7, BT-474, and SKBR3 cell lines. **p<0.01, ***p<0.001 and ****p<0.0001.