Evaluation of the antitumoral effect of dihydrocucurbitacin-B in both in vitro and in vivo models
- 178 Downloads
We evaluated both in vitro and in vivo antitumoral properties of an isolated compound from Wilbrandia ebracteata, dihydrocucurbitacin-B (DHCB), using B16F10 cells (murine melanoma).
Materials and methods
We made use of MTT and 3H-Thymidine assays to investigate the cell viability and cell proliferation, flow cytometry analysis to monitor cell cycle and apoptosis, western blot analysis to evaluate the expression of cell cycle proteins, imunofluorescence analysis and in vivo tumor growth and metastasis.
Dihydrocucurbitacin-B significantly reduced cell proliferation without important effects on cells viability. DHCB lead cells to accumulate in G2/M phases accompanied by the appearance of polyploid cells, confirmed by fluorescence assays that demonstrated a remarkable alteration in the cell cytoskeleton and formation of binuclear cells. Annexin-V-FITC incorporation demonstrated that DHCB did not induce apoptosis. About 10 μg/mL DHCB was found to decrease cyclin-A, and especially in cyclin-B1. The in vivo experiments showed that DHCB treatment (once a day up to 12 days; p.o.) was able to reduce the tumor growth and lung metastasis up to 83.5 and 50.3%, respectively.
Dihydrocucurbitacin-B reduces cell proliferation due to a decrease in the expression of cyclins, mainly cyclin-B1 and disruption of the actin cytoskeleton, arresting B16F10 cells in G2/M phase. Taken together, the in vitro and in vivo experiments suggest that DHCB was effective against cancer, however, it remains to be proved if DHCB will be a good candidate for drug development.
KeywordsDihydrocucurbitacin-B Cytoskeleton Cyclins Wilbrandia ebracteata
This study was supported by grants from the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Fundação de Apoio à Pesquisa Científica e Tecnológica de Santa Catarina (FAPESC) and Université de Sherbrooke, QC, Canada.
- 10.Blaskovich MA, Sun J, Cantor A, Turkson J, Jove R, Sebti SM (2003) Discovery of JSI-124 (cucurbitacin I), a selective Janus kinase/signal transducer and activator of transcription 3 signaling pathway inhibitor with potent antitumor activity against human and murine cancer cells in mice. Cancer Res 63:1270–1279PubMedGoogle Scholar
- 24.Peters RR, Krepsky PB, Siqueira-Junior JM, Rocha JCS, Bezerra MM, Ribeiro RA, de Brum-Fernandes AJ, Farias MR, Rocha FAC, Ribeiro-do-Valle RM (2003) Nitric oxide and cyclooxygenase may participate in the analgesic and anti-inflammatory effect of the cucurbitacins fraction from Wilbrandia ebracteata. Life Sci 73(17):2185–2197PubMedCrossRefGoogle Scholar
- 26.Valente LMM (2004) Cucurbitacins and their main structural characteristics. Quim Nova 27(6):944–948Google Scholar
- 29.Fernandez C, Lobo MdMdelV, Gomez-Coronado D, Lasuncion MA (2004) Cholesterol is essential for mitosis progression and its deficiency induces polyploid cell formation. Exp Cell Res 300:109–120Google Scholar