HYPOXIA induces lncRNA HOTAIR for recruiting RELA in papillary thyroid cancer cells to upregulate miR-181a and promote angiogenesis
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View abstract on PubMed
Summary
This summary is machine-generated.Hypoxia activates HOTAIR, which upregulates exosomal miR-181a by binding RELA. This exosomal miR-181a promotes papillary thyroid carcinoma angiogenesis by downregulating GATA6.
Area Of Science
- Molecular Biology
- Oncology
- Cell Biology
Background
- Papillary thyroid carcinoma (PTC) is a common thyroid cancer subtype.
- Exosomal microRNA-181a (miR-181a) is implicated in PTC development.
- This study investigates hypoxia's regulation of miR-181a and its role in angiogenesis.
Purpose Of The Study
- To elucidate the regulatory mechanism of miR-181a under hypoxia.
- To determine the impact of exosomal miR-181a on tumor angiogenesis.
- To identify key molecular players in this pathway.
Main Methods
- Ribonucleoprotein immunoprecipitation (RIP) and Chromatin Immunoprecipitation (ChIP-qPCR) to assess molecular interactions.
- Short hairpin RNA (shRNA) for gene knockdown and rescue experiments.
- Dual-luciferase assays to confirm promoter activity and functional assays (CCK8, EdU, Transwell, Western Blot) to evaluate angiogenesis and cell behavior.
Main Results
- HOTAIR binds RELA under hypoxia, leading to RELA-mediated upregulation of miR-181a.
- HOTAIR knockdown reduces miR-181a levels, which can be restored by RELA overexpression.
- Exosomal miR-181a downregulates GATA6, inhibiting HUVEC proliferation, migration, and tube formation, while also reducing EGFR expression.
Conclusions
- HOTAIR activates RELA to upregulate miR-181a during hypoxia.
- Exosomal miR-181a promotes tumor angiogenesis by downregulating GATA6.
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