Back to Search
Start Over
Oxocrebanine: A Novel Dual Topoisomerase inhibitor, Suppressed the Proliferation of Breast Cancer Cells MCF-7 by Inducing DNA Damage and Mitotic Arrest
- Source :
- Phytomedicine. 84:153504
- Publication Year :
- 2021
- Publisher :
- Elsevier BV, 2021.
-
Abstract
- Background DNA topoisomerase (Topo) inhibition plays key role in breast cancer treatment. Stephania hainanensis H. S. Lo et Y. Tsoong (S. hainanensis), a Li nationality plant that has abundant aporphine alkaloids, can inhibit Topo. Purpose To identify a dual Topo inhibitor, a deep and systematic study of active aporphine alkaloids in S. hainanensis and their mechanisms of inhibiting breast cancer proliferation and Topo activity are essential. Study design This study aimed to assess the anti-breast cancer and Topo inhibitory activities of oxocrebanine and explore the underlying mechanisms. Methods The growth inhibitory activities of 12 compounds in S. hainanensis were screened by MTT assay in MCF-7, SGC-7901, HepG-2 cells, and compared with the effects on human normal mammary epithelial MCF-10A cells as non cancer control cells. The Topo inhibitory activity was assessed by DNA relaxation and unwinding assays, kDNA decatenation assay and western blot. Cell cycle and autophagy analyses were carried out with flow cytometry and staining. Acridine orange staining and α-tubulin morphology were observed by fluorescence microscopy. Western blot was used to examine microtubule assembly dynamics and the expression levels of key proteins associated with DNA damage, autophagy and mitotic arrest. Results Oxocrebanine was the anti-breast cancer active alkaloid in S. hainanensis. It exhibited the best inhibitory effect on MCF-7 cells with an IC50 of 16.66 μmol/l, and had only weak effect on the proliferation of MCF-10A cells. Oxocrebanine inhibited Topo I and II α in a cell-free system and in MCF-7 cells. The DNA unwinding assay suggested that oxocrebanine intercalated with DNA as a catalytic inhibitor. Oxocrebanine regulated the levels of Topo I and IIα and DNA damage-related proteins. Oxocrebanine led to the mitotic arrest, and these effects occurred through both p53-dependent and p53-independent pathways. Oxocrebanine induced autophagy, abnormal α-tubulin morphology and stimulated enhanced microtubule dynamics. Conclusion Oxocrebanine was the anti-breast cancer active aporphine alkaloid in S. hainanensis. Oxocrebanine was a Topo I/IIα dual inhibitor, catalytic inhibitor and DNA intercalator. Oxocrebanine caused DNA damage, autophagy, and mitotic arrest in MCF-7 cells. Oxocrebanine also disrupted tubulin polymerization. Accordingly, oxocrebanine held a great potential for development as a novel dual Topo inhibitor for effective breast cancer treatment.
- Subjects :
- Aporphines
Topoisomerase Inhibitors
DNA damage
medicine.drug_class
Mitosis
Pharmaceutical Science
Breast Neoplasms
03 medical and health sciences
chemistry.chemical_compound
Alkaloids
0302 clinical medicine
Cell Line, Tumor
Drug Discovery
medicine
Humans
MTT assay
Aporphine
Cell Proliferation
030304 developmental biology
Pharmacology
0303 health sciences
biology
Chemistry
Topoisomerase
Cell Cycle
Acridine orange
Cell cycle
Antineoplastic Agents, Phytogenic
Molecular biology
DNA Topoisomerases, Type II
DNA Topoisomerases, Type I
Complementary and alternative medicine
MCF-7
030220 oncology & carcinogenesis
MCF-7 Cells
biology.protein
Molecular Medicine
Female
Drug Screening Assays, Antitumor
Topoisomerase inhibitor
DNA Damage
Subjects
Details
- ISSN :
- 09447113
- Volume :
- 84
- Database :
- OpenAIRE
- Journal :
- Phytomedicine
- Accession number :
- edsair.doi.dedup.....21a1ab36f068e12ba268e076e184e7f9