Curcumin,Khaya senegalensis,Atomic force microscopy,Glutathione,adenosine triphosphate,Metasis,Carcinoma, hepatocellular," /> Curcumin,Khaya senegalensis,Atomic force microscopy,Glutathione,adenosine triphosphate,Metasis,Carcinoma, hepatocellular,"/> Atomic force microscopy correlates antimetastatic potentials of HepG2 cell line with its redox/energy status: Effects of curcumin and <em>Khaya senegalensis</em>
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Journal of Integrative Medicine ›› 2017, Vol. 15 ›› Issue (3): 214-230.doi: 10.1016/S2095-4964(17)60337-6

Special Issue: Natural Drug

• Research Article • Previous Articles     Next Articles

Atomic force microscopy correlates antimetastatic potentials of HepG2 cell line with its redox/energy status: Effects of curcumin and Khaya senegalensis

Jeremiah Olorunjuwon Olugbamia,b,c, Robert Damoiseauxd,e, Bryan Franced, Michael A. Gbadegesina, Adam Z. Stiegb, Shivani Sharmab, Oyeronke A. Odunolaa, James K. Gimzewskib,c,f   

  1. a Cancer Research and Molecular Biology Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Oyo 200005, Nigeria 
    b Nano and Pico Characterization Laboratories, California NanoSystems Institute, University of California, Los Angeles, California 90095, USA 
    c Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA 
    d Molecular Screening and Shared Resources Laboratories, California NanoSystems Institute, University of California, Los Angeles, California 90095, USA 
    e Department of Molecular and Medicinal Pharmacology, University of California, Los Angeles, California 90095, USA 
    f International Center for Materials Nanoarchitectonics Satellite, National Institute for Materials Science, Tsukuba 3690114, Japan
  • Received:2016-11-15 Accepted:2017-02-01 Online:2017-05-15 Published:2017-05-15
  • Contact: James K. Gimzewski, PhD; E-mail:,


The fatality of cancer is mostly dependent on the possibility of occurrence of metastasis. Thus, if the development of metastasis can be prevented through novel therapeutic strategies targeted against this process, then the success of cancer treatment will drastically increase. In this study, therefore, we evaluated the antimetastatic potentials of an extract of Khaya senegalensis and curcumin on the metastatic liver cell line HepG2, and also assessed the anticancer property of the extract.


Cells were cultured and treated with graded concentrations of test substances for 24, 48, or 72 h with provisions made for negative controls. Treated cells were assessed as follows: nanotechnologically—atomic force microscopy (AFM) was used to determine cell stiffness; biochemically—cell cytotoxicity, glutathione level and adenosine triphosphate status, caspase activation and mitochondrial toxicity were considered; and microbiologically—a carrot disk assay was used to assess the anticancer property of the extract of K. senegalensis.


Curcumin and K. senegalensis increased the cell stiffness by 2.6- and 4.0-fold respectively, indicating their antimetastatic effects. Corresponding changes in redox (glutathione level) and energy (adenosine triphosphate) status of the cells were also demonstrated. Further mechanistic studies indicated that curcumin was not mitotoxic in HepG2 cells unlike the K. senegalensis extract. In addition, the extract potently inhibited the Agrobacterium tumefaciens-induced genetic transformation based on carrot disk assay.


Cell elasticity measurement data, using AFM, strongly suggested, for the first time, that both curcumin and the extract of K. senegalensis exhibited antimetastatic properties on HepG2 cells.

Key words: Curcumin, Khaya senegalensis, Atomic force microscopy, Glutathione, adenosine triphosphate, Metasis, Carcinoma, hepatocellular

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