Plasma miR-21, miR-155, miR-10b, and Let-7a as the potential biomarkers for the monitoring of breast cancer patients

Solmaz Khalighfard,Ali Mohammad Alizadeh,Ramesh Omranipour,Shiva Irani

doi:10.1038/s41598-018-36321-3

Abstract

There is a pressing need for further studies to categorize and validate circulating microRNAs (miRs) in breast cancer patients that can be one of the novel strategies for cancer screening and monitoring. The present study is aimed to investigate the expression of the circulating candidate microRNAs after the operation, chemotherapy, and radiotherapy in the non-metastatic breast cancer patients. Tumor tissue and plasma samples were collected from the 30 patients with recently diagnosed Luminal A breast cancer. Control plasma samples were collected from the 10 healthy subjects. A panel of four miRs including miR-21, miR-55, miR-10b, and Let-7a were selected and their expression levels were measured before and after the operation, chemotherapy, and radiotherapy by using Real-Time PCR technique. The plasma expression of the miR-21, miR-155, and miR-10b was significantly increased and the Let-7a plasma expression decreased in the breast cancer patients compromised to the control ones. There was a similar expression pattern of the miRs between the tissue and plasma samples. The plasma levels of the miR-21, miR-155, and miR-10b were significantly down-regulated and the Let-7a plasma level was up-regulated after the operation, chemotherapy, and radiotherapy compromised to the pre-treatment. There was a significant difference in the miR-155 plasma level after the operation, chemotherapy, and radiotherapy compromised with each other. Moreover, there was no significant difference between the plasma levels of the miRs after the radiotherapy compromised to the control cases. The operation, chemotherapy, and radiotherapy led to a more reduction in the oncomiRs and an increase in the tumor suppressor-miRs. It seems that monitoring miRs during treatment might be considered as a respectable diagnostic tool for monitoring of breast cancer patients.

Highlights

Breast cancer (BC) is the second leading cause of gynecological cancer deaths[1]
The results showed a similar expression pattern between them and there were no significant changes (Fig. 2)
Our results showed that the expression levels of the oncomiRs such as the miR-21, miR-10b, and miR-155 were significantly increased, while the expression level of the tumor suppressor such as the Let-7a was significantly decreased in the plasma of the patients

Summary

Introduction

The diagnosis of BC in the early stages, as well as monitoring of the disease progression and response to treatment, could be made easy with the aims of the liquid biopsy in the neoadjuvant setting[2] In this respect, existing diagnostic tools and biomarkers for BC have many inherent deficiencies[3]. An ideal biomarker should be accessible such that it can be sampled noninvasively and be sensitive enough to detect the early presence of tumors[4] This new approach has the potential to revolutionize clinical management including determining cancer classification, estimating prognosis, predicting therapeutic efficacy, maintaining surveillance following surgery as well as forecasting disease recrudescence[5]. Discovery of the roles of the miRs in developing BC may provide new opportunities for the development of the novel strategies for diagnosing and treating this type of the malignancy

Objectives

Results

Discussion

Conclusion