Related Experiment Video
Updated: Sep 14, 2025

Clinicopathological Analysis of miRNA Expression in Breast Cancer Tissues by Using miRNA In Situ Hybridization
Published on: June 7, 2016
Role of Micro RNA Expression as Biomarker in Breast Cancer
Gitika Nanda Singh1, Nijarth Shahi1, Parijat Suryavanshi1
1Department of General Surgery, King George's Medical University, Lucknow, Uttar Pradesh, India.
Background:
The most common cancer in women is breast cancer (BC). MicroRNA-21 was one of the first oncomiRs to be found at elevated levels in a number of malignancies, including gliomas, BC, and colorectal cancer (miR-21). MiRNA is associated with processes such as apoptosis, invasion, metastasis, and proliferation, which are known features of cancer. This study aimed to investigate the molecular basis and clinical significance of miR-21 in BC, as microRNAs play a critical role in this disease.
Materials And Methods:
MiR 21 was then analyzed by the quantitative polymerase chain reaction (qPCR) using the Taq-Man probe. The thermal profile included 5 min of denaturation at 95°C, then 40 cycles of denaturation at 95°C for 20 s, annealing at 52°C for 20 s, and extension at 72°C for 30 s. Two separate runs of real-time polymerase chain reaction and reverse transcription (RT) were then performed. Relative quantification of the gene expression levels (fold change) based on computed tomography values was used to examine the data from RT-qPCR for miR-21 and Glyceraldehyde-3-phosphate dehydrogenase (Livak and Schmittgen).
Results:
The mean fold change in serum miR-21 levels was significantly higher in cases (8.17 ± 2.49) than in controls (1.02 ± 0.23). The mean fold change in serum miR-21 levels in Stages III, IV and lymph nodes were significantly higher than in Stages I and II. The mean fold change in serum miR-21 gene expression was significant with the changes in different Ki67 levels.
Conclusions:
Our results demonstrate the importance of miR-21 plasma level as a diagnostic and prognostic biomarker for BC.
Insights
MicroRNA-21 (miR-21) is elevated in breast cancer (BC) patients, correlating with advanced stages and lymph node involvement. This finding highlights miR-21 as a potential biomarker for diagnosing and predicting BC outcomes.
Area of Science:
- Oncology
- Molecular Biology
- Biochemistry
Background:
- Breast cancer (BC) is the most common malignancy in women.
- MicroRNA-21 (miR-21) is an oncomiR found at elevated levels in various cancers, including BC.
- MicroRNAs regulate critical cancer processes like apoptosis, invasion, metastasis, and proliferation.
Purpose of the Study:
- To investigate the molecular basis of miR-21 in breast cancer.
- To determine the clinical significance of miR-21 as a biomarker in BC.
Main Methods:
- Quantitative polymerase chain reaction (qPCR) with Taq-Man probe was used to analyze miR-21 levels.
- Real-time polymerase chain reaction and reverse transcription (RT) were performed.
- Relative quantification of gene expression (fold change) was calculated using RT-qPCR data.
Main Results:
- Serum miR-21 levels were significantly higher in BC cases (8.17 ± 2.49) compared to controls (1.02 ± 0.23).
- Elevated miR-21 levels correlated with advanced BC stages (III, IV) and lymph node metastasis.
- miR-21 expression showed a significant association with Ki67 protein levels.
Conclusions:
- Plasma miR-21 levels serve as a valuable diagnostic biomarker for breast cancer.
- miR-21 is a significant prognostic biomarker for predicting breast cancer outcomes.

