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Updated: Oct 6, 2025
16:01
Investigating Mast Cell Secretory Granules; from Biosynthesis to Exocytosis
Published on: January 26, 2015
13.3K
Exocyst controls exosome biogenesis via Rab11a
Suwen Bai1,2, Wenxuan Hou2, Yanheng Yao2
1Longgang District People's Hospital of Shenzhen & The Second Affiliated Hospital of The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, China.
Molecular Therapy. Nucleic Acids
|January 17, 2022
Summary
Exosomes regulate head and neck cancer (HNC) biology. The exocyst complex promotes exosome secretion and tumor cell proliferation in HNC, offering potential therapeutic targets.
Area of Science:
- Oncology
- Cell Biology
- Cancer Research
Background:
- Tumor cells release exosomes, influencing cancer biology, including head and neck cancer (HNC).
- Exosome biogenesis and release share similarities with exocyst-mediated vesicle transport.
Purpose of the Study:
- To analyze exocyst subunit expression and function in HNC.
- To investigate the exocyst's role in exosome biogenesis and transport regulation in HNC cells.
Main Methods:
- Analysis of exocyst subunit expression in HNC patients.
- Knockdown of exocyst in HN4 cells.
- Immunofluorescence and electron microscopy.
- Assessment of exosome secretion, cell proliferation, and multivesicular body (MVB) accumulation.
Main Results:
- Exocysts were highly expressed in HNC cells, promoting exosome secretion.
- Exocyst downregulation inhibited HN4 cell proliferation via reduced exosome secretion.
- Exocyst knockdown led to MVB accumulation, with autophagy not activated unless induced by starvation.
- Rab11a interacted with the exocyst.
Conclusions:
- The exocyst complex regulates exosome biogenesis and secretion in HNC.
- Exocyst-mediated exosome transport contributes to the malignant behavior of HNC cells.
- The exocyst represents a potential therapeutic target for HNC treatment.
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