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MicroRNA-21 as a predictor and prognostic factor for trastuzumab therapy in human epidermal growth factor receptor

Marwa Badr1, Hebatallah Said1, Manal L Louka1

  • 1Department of Medical Biochemistry and Molecular Biology, Faculty of Medicine, Ain Shams University, Cairo, Egypt.

Journal of Cellular Biochemistry
|September 25, 2018
PubMed

Insights

Serum microRNA-21 (miR-21) levels significantly decreased after trastuzumab treatment in HER2-positive metastatic breast cancer patients. Lower miR-21 levels correlated with longer time to progression, suggesting miR-21 as a potential prognostic factor.

Area of Science:

  • Oncology
  • Molecular Biology
  • Biochemistry

Background:

  • Breast cancer is a prevalent malignancy, with HER2-positive subtypes accounting for 20-30% of cases.
  • Trastuzumab is a standard therapy for HER2-positive breast cancer.
  • MicroRNA-21 (miR-21) is an oncomiR implicated in tumor progression by suppressing tumor-suppressor genes.

Purpose of the Study:

  • To investigate the change in serum miR-21 levels in HER2-positive metastatic breast cancer patients treated with trastuzumab.
  • To evaluate the correlation between miR-21 expression and treatment response or time to progression.

Main Methods:

  • Serum samples were collected from 20 HER2-positive metastatic breast cancer patients before and after 3 months of trastuzumab therapy.
  • Relative expression levels of miR-21 were quantified.
  • Statistical analysis was performed to assess changes in miR-21 levels and correlations with clinical outcomes.

Main Results:

  • Serum miR-21 levels showed a statistically significant decrease (P=0.001) after trastuzumab treatment.
  • While responders tended to have lower miR-21 levels than non-responders, this difference was not statistically significant (P=0.6).
  • A significant negative correlation was observed between basal and post-treatment miR-21 levels and time to progression (P=0.03 and P=0.01, respectively).

Conclusions:

  • Serum miR-21 levels significantly decrease following trastuzumab therapy in HER2-positive metastatic breast cancer.
  • miR-21 may serve as a potential prognostic biomarker for HER2-positive metastatic breast cancer.
  • miR-21 inhibition using antisense oligonucleotides could be a potential therapeutic strategy.
Keywords:
breast cancerhuman epidermal growth factor receptor 2microRNA-21trastuzumab

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