Clinacanthus Nutans Hexane Extracts Induce Apoptosis Through a Caspase-Dependent Pathway in Human Cancer Cell Lines
Pei Ying Ng1,2, Soi Moi Chye, Chew Hee Ng
1School of Health Sciences, International Medical University, Kuala Lumpur, Malaysia.
Abstract:
Background: Clinacanthus nutans (C.nutans) is a plant consumed as a cancer treatment in tropical Asia. Despite the availability of numerous anecdotal reports, evaluation of active anticancer effects has remained elusive. Therefore we here examined antiproliferative, reactive oxygen species (ROS)-inducing and apoptosis mechanisms of whole plant extracts in different cancer cell lines. Methods: Antiproliferative actions of five solvent extracts (hexane, chloroform, ethyl acetate, methanol and water) of C.nutans were tested on non-small cell lung cancer (A549), nasopharygeal cancer (CNE1) and liver cancer (HepG2) cells using MTT assay. The most potent anticancer extract was then assessed by flow cytometry to study cell cycle changes . Intracellular levels of ROS were quantified by DCFH-DA assay. Involvement of the caspase pathway in induction of apoptosis was assessed using caspase assay kits. GC-MS analysis was performed to identify phytoconstituents in the extracts. Results: Hexane and chloroform extracts were antiproliferative against all three cell lines, while the ethyl acetate extract, at 300 μg/mL, was antiproliferative in the CNE1 but not A549 and HepG2 cases. Methanol and water extracts did not inhibit cancer cell proliferation. The most potent anticancer hexane extract was selected for further testing. It induced apoptosis in all three cell lines as shown by an increase in the percentage of cell in sub-G1 phase. Dose-dependent increase in ROS levels in all three cell lines indicated apoptosis to be possibly modulated by oxidative stress. At high concentrations (>100 μg/mL), hexane extracts upregulated caspases 8, 9 and 3/7 across all three cell lines. GC-MS analysis of the hexane extract revealed abundance of 31 compounds. Conclusion : Among the five extracts of C.nutans, that with hexane extract demonstrated the highest antiproliferative activity against all three cancer cell lines tested. Action appeared to be via ion of intracellular ROS, and induction of apoptosis via intrinsic and extrinsic caspase pathways.
Insights
Clinacanthus nutans hexane extract shows potent anticancer effects by inducing apoptosis and reactive oxygen species (ROS) in lung, nasopharyngeal, and liver cancer cells. Further research is warranted to explore its therapeutic potential.
Area of Science:
- Phytochemistry
- Cancer Biology
- Pharmacology
Background:
- Clinacanthus nutans (C. nutans) is traditionally used in tropical Asia for cancer treatment.
- Scientific evaluation of C. nutans' anticancer properties is limited, despite anecdotal evidence.
- This study investigates the antiproliferative and apoptosis-inducing mechanisms of C. nutans extracts.
Purpose of the Study:
- To evaluate the antiproliferative activity of C. nutans solvent extracts against lung, nasopharyngeal, and liver cancer cell lines.
- To elucidate the mechanisms of action, including reactive oxygen species (ROS) generation and apoptosis induction.
- To identify key phytoconstituents responsible for the observed anticancer effects.
Main Methods:
- Five solvent extracts (hexane, chloroform, ethyl acetate, methanol, water) of C. nutans were tested.
- Antiproliferative effects were assessed using MTT assay on A549, CNE1, and HepG2 cancer cell lines.
- Apoptosis, cell cycle changes, ROS levels, and caspase pathway involvement were analyzed using flow cytometry, DCFH-DA assay, and caspase assay kits. GC-MS was used for phytoconstituent identification.
Main Results:
- Hexane and chloroform extracts exhibited significant antiproliferative activity against all tested cancer cell lines.
- The hexane extract induced apoptosis, evidenced by an increase in sub-G1 phase cells and dose-dependent ROS generation.
- Hexane extract upregulated caspases 8, 9, and 3/7, indicating activation of both intrinsic and extrinsic apoptotic pathways. GC-MS identified 31 compounds in the hexane extract.
Conclusions:
- The hexane extract of C. nutans demonstrated the most potent antiproliferative activity against lung, nasopharyngeal, and liver cancer cells.
- The anticancer effects are mediated through intracellular ROS induction and apoptosis via caspase pathway activation.
- C. nutans, particularly its hexane extract, holds potential as a source for novel anticancer therapeutics.
Related Concept Videos
01:31The Intrinsic Apoptotic Pathway
01:24Caspases
01:17The Extrinsic Apoptotic Pathway
01:30Apoptosis
01:30Overview of Cell Death
Cell death was observed in the early 19th century, but there was no experimental evidence to prove it. In 1842, Carl Vogt first discovered cell death in a metamorphic toad; however, it was not termed ‘cell death.’ Scientists discovered different cell death pathways only in the...