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Updated: Aug 9, 2025
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Co-immunoprecipitation Assay Using Endogenous Nuclear Proteins from Cells Cultured Under Hypoxic Conditions
Published on: August 2, 2018
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MiR-21 Is Induced by Hypoxia and Down-Regulates RHOB in Prostate Cancer
Charlotte Zoe Angel1,2, Mei Yu Cynthia Stafford1, Christopher J McNally1
1Genomic Medicine Research Group, Ulster University, Cromore Road, Coleraine BT52 1SA, UK.
Cancers
|February 25, 2023
Summary
Hypoxia, or low oxygen, drives microRNA-21 (miR-21) over-expression in prostate cancer, promoting tumour progression by suppressing the RHOB gene. MiR-21 shows potential as a biomarker for hypoxia and prostate cancer outcomes.
Area of Science:
- Oncology
- Molecular Biology
- Genetics
Background:
- Tumour hypoxia is a known driver of prostate cancer progression.
- Hypoxia influences microRNA expression, but miR-21's role in hypoxic prostate tumours is unclear.
- MicroRNA-21 (miR-21) over-expression is linked to various cancers.
Purpose of the Study:
- To investigate the relationship between hypoxia and miR-21 in prostate cancer.
- To determine if hypoxia up-regulates miR-21 in prostate cancer cells and tumours.
- To explore miR-21's functional role and potential as a biomarker.
Main Methods:
- Bioinformatic analysis of The Cancer Genome Atlas (TCGA) prostate cancer datasets.
- In vitro studies using LNCaP prostate cancer cell lines.
- In vivo studies using prostate tumour xenograft models.
- Functional enrichment analysis and in silico validation.
Main Results:
- miR-21 up-regulation is significantly associated with prostate cancer and disease progression markers.
- Hypoxia was confirmed to cause miR-21 over-expression in vitro and in vivo.
- miR-21 promotes cell migration and colony formation, and down-regulates the tumour suppressor gene RHOB.
- miR-21 expression levels correlate with patient outcomes post-therapy.
Conclusions:
- Hypoxia is a key driver of miR-21 over-expression in prostate tumours.
- miR-21 promotes prostate cancer progression by suppressing RHOB.
- miR-21 holds significant potential as a diagnostic and prognostic biomarker for hypoxia and prostate cancer.
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