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Updated: Jan 30, 2026
LINE-1 Methylation Analysis in Mesenchymal Stem Cells Treated with Osteosarcoma-Derived Extracellular Vesicles
Published on: February 1, 2020
Activation of dynamin-related protein 1 - dependent mitochondria fragmentation and suppression of osteosarcoma by
Jia-Hau Yen1, Hung Sen Huang1, Chia Ju Chuang1
1Research Cancer Center for Traditional Chinese Medicine, Department of Medical Research, China Medical University Hospital, Taichung, Taiwan.
Background:
Discovering how to regulate mitochondrial function to reduce cancer growth holds great potential for future cancer therapy development. Here we explore the effects of cryptotanshinone (CPT), a natural product derived from Salvia miltiorrhiza, on mitochondria of osteosarcoma (OS) both in vitro and in vivo, and further elucidate the underlying molecular mechanisms.
Methods:
Cytotoxicity in the CPT treated OS cells was analyzed by flow cytometry, CCK8, TUNEL assay and colony formation assays. Flow cytometric analysis was performed to evaluate the effect of CPT on cell cycle of OS cells. Mitochondrial morphology was examined by staining with the mitochondrial membrane potential -sensitive fluorochrome, MitoTracker Red (CMXRos). Immunoblotting, confocal-immunofluorescence staining, co-immunoprecipitation were used to examine the expression and interaction between CPT-mediated Drp1 and Bax. Finally, the synergistic effect of CPT on OS cells was validated using a mouse xenograft tumor model.
Results:
In this study, we found CPT treatment induced S-phase arrest, apoptosis, and mitochondrial fragmentation in OS cells. CPT also effectively activated caspase-dependent apoptosis, which could be blocked by pan-caspase inhibitor Z-VAD-FMK. Moreover, we herein provide evidence that treatment with CPT resulted in mitochondrial fragmentation, which is mediated by dynamin-related protein 1 (Drp1), a key mediator of mitochondrial fission. Pursuing this observation, downregulation of Drp1 via silencing RNA could abrogate the induction of apoptosis and mitochondrial fragmentation induced by CPT. Finally, we demonstrate that CPT induced Drp1, which interacted directly with Bcl-2-associated X protein (Bax), which contributed to driving Bax translocation from the cytosol to the mitochondria.
Conclusions:
Our findings offer insight into the crosstalk between mitochondrial fragmentation and inhibition of osteosarcoma cell growth in response to CPT.
Insights
Cryptotanshinone (CPT) induces osteosarcoma cell death by causing mitochondrial fragmentation via dynamin-related protein 1 (Drp1) and Bcl-2-associated X protein (Bax) interaction. This natural compound shows promise for cancer therapy by targeting mitochondrial pathways.
Area of Science:
- Mitochondrial biology
- Cancer research
- Pharmacology
Background:
- Mitochondrial function regulation is a promising strategy for cancer therapy.
- Osteosarcoma (OS) is a challenging bone cancer.
- Cryptotanshinone (CPT), a natural product, is investigated for its effects on OS.
Purpose of the Study:
- To investigate the effects of CPT on osteosarcoma cell mitochondria.
- To elucidate the molecular mechanisms underlying CPT's action.
- To evaluate CPT's therapeutic potential in osteosarcoma.
Main Methods:
- Cytotoxicity, cell cycle, and apoptosis assays (flow cytometry, CCK8, TUNEL, colony formation).
- Mitochondrial morphology assessment using MitoTracker Red.
- Analysis of protein expression and interaction (immunoblotting, immunofluorescence, co-immunoprecipitation) for Drp1 and Bax.
- In vivo validation using a mouse xenograft tumor model.
Main Results:
- CPT induced S-phase arrest, apoptosis, and mitochondrial fragmentation in OS cells.
- CPT activated caspase-dependent apoptosis, mediated by dynamin-related protein 1 (Drp1) and Bcl-2-associated X protein (Bax).
- CPT treatment led to Drp1-mediated mitochondrial fission and subsequent Bax translocation to mitochondria.
Conclusions:
- CPT triggers osteosarcoma cell death through mitochondrial fragmentation.
- The findings highlight the interplay between mitochondrial dynamics and cancer cell growth inhibition.
- CPT demonstrates potential as an anti-osteosarcoma agent targeting mitochondrial pathways.
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