Correlation between the expression profile of microRNAs found in plasma and the presence or absence of malignant breast lesions in patients with mammography BI-RADS 4

Abstract

MiRNAs are a class of non-coding RNAs that regulate post-transcriptionally the stability of mRNA. Recently it was discovered that human serum/plasma contains a large amount of the stable miRNAs and the differential expression of these miRNAs is being used as a molecular marker for the detection of various diseases, including cancer. Breast cancer is the most common cancer in women and is the leading cause of death in women worldwide. The main factor contributing to increase the chance of cure in breast cancer patients is early detection. It is therefore recommended that mammographies are performed regularly. The standardization of mammography is performed by the BI-RADS values that separate the malignant lesions, benign and suspicious. However, BI-RADS classification resolves those lesions classified in stages 1, 2 and 5, but patients in the BI-RADS 3 category have ambiguous lesions and BI-RADS 4 patients have suspicious lesions. In this context, it is necessary to identify new methods to assist in the mammography interpretation. Recent studies have shown that the expression of miRNAs in plasma of cancer patients is aberrantly deregulated. Therefore, we aim to establish a miRNA profile present in the plasma of BI-RADS 4 women that can separate malignant from benign lesions. We will evaluate the miRNA profile present in the plasma samples of 100 patients with breast cancer (BI-RADS 5) and 100 control patients (BI-RADS 1 and 2) from Hospital Sírio Libanês, to find a profile that separates the groups. To validate the targets, the miRNA profile of other 100 patients BI-RADS 4 will be evaluated and the result will be compare with the presence or absence of malignant lesions. We will use the miRNA PCR arrays system that can detect 1066 human miRNAs by quantitative real time PCR. We will thus evaluate in a large number of samples, the largest possible number of miRNA sequences and identify a profile that can reliably differentiate breast lesions to assist in the diagnosis and treatment of breast cancer. (AU)