Combination of circulating miR-145-5p/miR-191-5p as biomarker for breast cancer detection

Abstract

Background: Breast cancer (BC) is the most common cancer among women worldwide. At present, there is a need to search for new, accurate, reliable, minimally invasive and cheap biomarkers in addition to existing methods for the diagnosis and prognosis of BC. The main goal of this study was to test the diagnostic value of six circulating miRNAs in Kazakh women.

Materials and methods: TaqMan-based miRNA profiling was conducted using plasma specimens from 35 BC women patients and 33 healthy women samples (control group).

Results: The level of all seven miRNAs (including endogenous control) normalized by synthetic cel-miR-39 were significantly elevated in the group of BC patients. Normalization using miR-222-3p as endogenous control reduced differences in level of miRNAs between groups; as a result, only three miRNAs were significantly upregulated in the group of BC patients-miR-145-5p (P = 6.5e-12), miR-191-5p (P = 3.7e-10) and miR-21-5p (P = 0.0034). Moreover, ROC analysis showed that the use of miR-145-5p and miR-191-5p, both individually (AUC = 0.931 and 0.904, respectively) or in combination (AUC = 0.984), allows to accurately differentiate BC patients from healthy individuals.

Conclusions: Two plasma miRNAs-miR-145-5p and miR-191-5p-are potential biomarkers for diagnosis of BC in the Kazakh population. The findings need to be further substantiated using a more representative sample.

Keywords: Biomarker; Breast cancer; Circulating miRNA; Diagnosis; Kazakh population; Plasma; miR-145; miR-191; miR-21.

Figure 1. Selection of endogenous control.

(A) Results from NormFinder: intergroup (bars) and intragroup (whiskers) variation plot and stability value (SV), calculated on their basis; (B) average expression stability values of remaining control candidates during stepwise exclusion of the least stable control candidate, obtained from GeNorm.

Figure 2. Differences in ΔCt between BC patients and control group.

(A) Data are normalized to the spike-in control cel-miR-39; (B) data are normalized to the endogenous control miR-222-3p.

Figure 3. ROC plots for miRNAs, showing significant differences in plasma levels between BC patients group and control group.

(A) miR-145-5p, miR-191-5p and miR-21-5p, normalized to cel-miR-39; (B) miR-16-5p, miR-210-3p, miR-222-3p and miR-29c-3p, normalized to cel-miR-39; (C) miR-145-5p, miR-191-5p and miR-21-5p, normalized to miR-222-3p; (D) Combination of miR-145-5p and miR-191-5p, normalized to miR-222-3p.