Figure 7. Effect of candidate EC selection on relative expression of target miRNAs.

This figure demonstrates the impact of candidate EC selection on the accuracy of target miRNA expression. The relative expression of three target miRNAs (miR-93, miR-181a and miR-652) is presented following normalization using each of four distinct EC strategies: U6 alone, miR-16 alone, miR-425 alone and finally miR-16 and miR-425 in combination. Interval plots depict mean and 95% confidence intervals for relative miRNA expression (Log₁₀) in the blood of women with breast cancer (blue) and healthy controls (orange) normalized to different candidate ECs with p-values indicated in the table below. A. MiR-93 expression. MiR-93 appears to be elevated in the circulation of women with breast cancer when U6 was used to normalise RQ data. However, when the other EC candidates are used for normalization there is no difference in miR-93 expression between the cancer and control group. B. MiR-181a expression. MiR-181a is underexpressed with mIR-16 was used to normalise RQ data (p = 0.011). There is no difference in miR-181a expression when other EC candidates are used for normalization. C. MiR-652. MiR-652 is under-expressed in the circulation of women with breast cancer, regardless of the choice of candidate EC (U6, miR-425 or miR-16) indicating that it was highly differentially expressed in blood of those with breast cancer.