Related Experiment Video
Updated: May 31, 2026

Exploring the Pharmacological Action and Molecular Mechanism of Salidroside in Inhibiting MCF-7 Cell Proliferation and Migration
Published on: June 9, 2023
Anticancer activity of thymoquinone in breast cancer cells: possible involvement of PPAR-γ pathway
Chern Chiuh Woo1, Ser Yue Loo, Veronica Gee
1Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
Abstract:
Thymoquinone (TQ), an active ingredient of Nigella sativa, has been reported to exhibit anti-oxidant, anti-inflammatory and anti-tumor activities through mechanism(s) that is not fully understood. In this study, we report the anticancer effects of TQ on breast cancer cells, and its potential effect on the PPAR-γ activation pathway. We found that TQ exerted strong anti-proliferative effect in breast cancer cells and, when combined with doxorubicin and 5-fluorouracil, increased cytotoxicity. TQ was found to increase sub-G1 accumulation and annexin-V positive staining, indicating apoptotic induction. In addition, TQ activated caspases 8, 9 and 7 in a dose-dependent manner. Migration and invasive properties of MDA-MB-231 cells were also reduced in the presence of TQ. Interestingly, we report for the first time that TQ was able to increase PPAR-γ activity and down-regulate the expression of the genes for Bcl-2, Bcl-xL and survivin in breast cancer cells. More importantly, the increase in PPAR-γ activity was prevented in the presence of PPAR-γ specific inhibitor and PPAR-γ dominant negative plasmid, suggesting that TQ may act as a ligand of PPAR-γ. Also, we observed using molecular docking analysis that TQ indeed formed interactions with 7 polar residues and 6 non-polar residues within the ligand-binding pocket of PPAR-γ that are reported to be critical for its activity. Taken together, our novel observations suggest that TQ may have potential implication in breast cancer prevention and treatment, and show for the first time that the anti-tumor effect of TQ may also be mediated through modulation of the PPAR-γ activation pathway.
Insights
Thymoquinone (TQ), from Nigella sativa, shows anticancer effects on breast cancer by inducing apoptosis and reducing cell migration. This study reveals TQ activates the PPAR-γ pathway, suggesting a new therapeutic target for breast cancer treatment.
Area of Science:
- Oncology
- Pharmacology
- Molecular Biology
Background:
- Thymoquinone (TQ), derived from Nigella sativa, possesses known antioxidant, anti-inflammatory, and anti-tumor properties.
- The precise mechanisms underlying TQ's anti-tumor effects, particularly in breast cancer, remain incompletely elucidated.
- The potential role of the Peroxisome Proliferator-Activated Receptor gamma (PPAR-γ) pathway in TQ's action is under investigation.
Purpose of the Study:
- To investigate the anticancer effects of Thymoquinone (TQ) on breast cancer cells.
- To explore the potential involvement of the PPAR-γ activation pathway in TQ's anti-cancer mechanisms.
- To assess TQ's impact on breast cancer cell proliferation, apoptosis, and invasiveness.
Main Methods:
- Cell proliferation assays and cytotoxicity assessments with combination therapy (doxorubicin, 5-fluorouracil).
- Flow cytometry for sub-G1 accumulation and annexin-V staining to detect apoptosis.
- Caspase activity assays, cell migration, and invasion assays.
- PPAR-γ activity assays, gene expression analysis (Bcl-2, Bcl-xL, survivin), and molecular docking studies.
Main Results:
- TQ demonstrated significant anti-proliferative effects on breast cancer cells and enhanced cytotoxicity when combined with standard chemotherapeutics.
- TQ induced apoptosis, evidenced by increased sub-G1 phase accumulation and positive annexin-V staining, and activated caspases 8, 9, and 7.
- TQ inhibited cell migration and invasion, increased PPAR-γ activity, and downregulated key survival genes (Bcl-2, Bcl-xL, survivin).
- Molecular docking confirmed TQ's interaction with critical residues in the PPAR-γ ligand-binding pocket, suggesting it acts as a PPAR-γ ligand.
Conclusions:
- Thymoquinone exhibits potent anticancer properties against breast cancer cells, including induction of apoptosis and inhibition of migration/invasion.
- TQ modulates the PPAR-γ activation pathway, suggesting a novel mechanism for its anti-tumor effects.
- These findings highlight Thymoquinone's potential as a therapeutic agent or preventative strategy for breast cancer, possibly via PPAR-γ modulation.
Related Concept Videos
mTOR Signaling and Cancer Progression
The mTOR pathway or the...
mTOR Signaling and Cancer Progression
The mTOR pathway or the...
Cancer-Critical Genes II: Tumor Suppressor Genes
When the function of certain critical genes, especially those involved in cell cycle regulation and cell growth signaling cascades, gets disrupted, it upsets the cell cycle progression. Such cells with unchecked cell cycles start proliferating uncontrollably and eventually develop into tumors.
Such genes that act...
Cancer-Critical Genes II: Tumor Suppressor Genes
When the function of certain critical genes, especially those involved in cell cycle regulation and cell growth signaling cascades, gets disrupted, it upsets the cell cycle progression. Such cells with unchecked cell cycles start proliferating uncontrollably and eventually develop into tumors.
Such genes that act...
Targeted Cancer Therapies
There are several types of targeted therapies against specific...
Inhibition of Cdk Activity
