Related Experiment Videos
Set9, NF-κB, and microRNA-21 mediate berberine-induced apoptosis of human multiple myeloma cells
Hai-yan Hu1, Kun-peng Li, Xiu-ju Wang
1Oncology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
Aim:
To investigate the mechanisms by which berberine suppressed the proliferation of human multiple myeloma cells.
Methods:
Human U266 multiple myeloma cell line was tested. Cell proliferation, apoptosis, ultramicrostructure and secretion function were examined using Cell Counting Kit-8 (CCK8), flow cytometry (FCM), electron and fluorescence microscopy, as well as ELISA assay. The microRNAs (miRs) and transcription factors in U266 cells were detected using arrays and verified by qRT-PCR. EMSA and luciferase assays were used to verify the p65-dependent transactivation of miR-21 gene.
Results:
Treatment of U266 cells with berberine (40-160 μmol/L) suppressed cell proliferation and IL-6 secretion in dose- and time-dependent manners. Meanwhile, berberine dose-dependently induced ROS generation, G(2)/M phase arrest and apoptosis in U266 cells, and decreased the levels of miR-21 and Bcl-2. Overexpression of miR-21 counteracted berberine-induced suppression of cell proliferation and IL-6 secretion. In U266 cells treated with berberine (80 μmol/L), the activity of NF-κB was decreased by approximately 50%, followed by significant reduction of miR-21 level. berberine (80-160 μmol/L) increased the level of Set9 (lysine methyltransferase) by more than 2-fold, caused methylation of the RelA subunit, which inhibited NF-κB nuclear translocation and miR-21 transcription. In U266 cells treated with berberine (80 μmol/L), knockdown of Set9 with siRNAs significantly increased NF-κB protein level accompanying with a partial recovery of proliferation.
Conclusion:
In U266 cells, berberine suppresses NF-κB nuclear translocation via Set9-mediated lysine methylation, leads to decrease in the levels miR21 and Bcl-2, which induces ROS generation and apoptosis.
Insights
Berberine inhibits multiple myeloma cell growth by blocking NF-κB signaling. This natural compound reduces miR-21 and Bcl-2 levels, promoting cell death through ROS generation.
Area of Science:
- Molecular Biology
- Cancer Research
- Pharmacology
Background:
- Multiple myeloma is a hematological malignancy characterized by uncontrolled proliferation of plasma cells.
- Identifying novel therapeutic agents that target specific molecular pathways is crucial for improving patient outcomes.
Purpose of the Study:
- To elucidate the molecular mechanisms underlying berberine's anti-proliferative effects on human multiple myeloma cells.
- To investigate the role of NF-κB signaling, microRNAs, and apoptosis in berberine's action.
Main Methods:
- Utilized the U266 human multiple myeloma cell line.
- Assessed cell proliferation (CCK8), apoptosis (FCM), and IL-6 secretion (ELISA).
- Analyzed microRNA and transcription factor expression using arrays and qRT-PCR.
- Employed EMSA and luciferase assays to confirm gene transactivation pathways.
Main Results:
- Berberine suppressed U266 cell proliferation and IL-6 secretion in a dose- and time-dependent manner.
- Berberine induced ROS generation, G(2)/M phase arrest, and apoptosis, while decreasing miR-21 and Bcl-2 levels.
- Berberine inhibited NF-κB nuclear translocation via Set9-mediated lysine methylation, reducing miR-21 transcription.
Conclusions:
- Berberine effectively suppresses multiple myeloma cell proliferation and IL-6 secretion.
- The mechanism involves Set9-mediated inhibition of NF-κB nuclear translocation, leading to decreased miR-21 and Bcl-2.
- This pathway induces reactive oxygen species (ROS) generation and apoptosis in multiple myeloma cells.
Related Concept Videos
02:26NF-κB-dependent Signaling Pathway
NF-κB-dependent Signaling Mechanism
The heterodimer of NF-κB...
01:31The Intrinsic Apoptotic Pathway