BIOACTIVE MARINE-DERIVED COMPOUNDS AS POTENTIAL ANTICANCER CANDIDATES

Objective: The objective of this research was to evaluate for the 1st time the anticancer activities of sarcophytol M (1), alismol (2), alismoxide (5), 7β-acetoxy-24-methylcholesta-5-24(28)-diene-3,19-diol (7), erythro-N-dodecanoyl-docosasphinga-(4E,8E)-dienine (8), and 24 methylcholesta- 5,24(28)-diene-3β,7β,19-triol (9). Compounds were isolated from the soft coral Lithophyton arboreum and tested in liver (HepG2), lung (A549), and breast (MDA) cancer cell line.Methods: Anticancer activities of the compounds were tested using (XTT) 2,3-bis-(2-methoxy-4-nitro- 5-sulfophenyl)-2H-tetrazolium-5-carboxanilide, Na2) in vitro assay in order to estimate the cytotoxicity and to determine the IC50s. The free radical scavenging activity of the compounds were measured by 1,1-diphenyl-2-picryl-hydrazil (DPPH•). All compounds were screened at 100 μg/ml while the most potent active compounds were assayed at lower concentrations.Results: Compounds (7) and (9) showed a strong cytotoxic effect with IC50 of 6.07, 8.5 μg/ml in HepG2, 6.3, 5.5 μg/ml in MDA cells, and 5.2, 9.3 μg/ml in A549 cancer cell lines, respectively. In addition, moderate cytotoxicity was shown by compound (2) (IC50 16.5, 15, and 13 μg/mL) in HepG2, MDA, and A549 cancer cell lines, respectively.Conclusion: The results obtained in this research work indicated a promising potential cytotoxicity of compounds (7) and (9) compared to its safety margins in Vero cells, and the expected cytostatic effect of compound (2) can be used in drug cocktails for the treatment of the major cancer types' lung, breast, and liver cancer.Â

Cytotoxic and HIV-1 enzyme inhibitory activities of Red Sea marine organisms

BACKGROUND: Cancer and HIV/AIDS are two of the greatest public health and humanitarian challenges facing the world today. Infection with HIV not only weakens the immune system leading to AIDS and increasing the risk of opportunistic infections, but also increases the risk of several types of cancer. The enormous biodiversity of marine habitats is mirrored by the molecular diversity of secondary metabolites found in marine animals, plants and microbes which is why this work was designed to assess the anti-HIV and cytotoxic activities of some marine organisms of the Red Sea. METHODS: The lipophilic fractions of methanolic extracts of thirteen marine organisms collected from the Red Sea (Egypt) were screened for cytotoxicity against two human cancer cell lines; leukaemia (U937) and cervical cancer (HeLa) cells. African green monkey kidney cells (Vero) were used as normal non-malignant control cells. The extracts were also tested for their inhibitory activity against HIV-1 enzymes, reverse transcriptase (RT) and protease (PR). RESULTS: Cytotoxicity results showed strong activity of the Cnidarian Litophyton arboreum against U-937 (IC50; 6.5 μg/ml ±2.3) with a selectivity index (SI) of 6.45, while the Cnidarian Sarcophyton trochliophorum showed strong activity against HeLa cells (IC50; 5.2 μg/ml ±1.2) with an SI of 2.09. Other species showed moderate to weak cytotoxicity against both cell lines. Two extracts showed potent inhibitory activity against HIV-1 protease; these were the Cnidarian jelly fish Cassiopia andromeda (IC50; 0.84 μg/ml ±0.05) and the red algae Galaxura filamentosa (2.6 μg/ml ±1.29). It is interesting to note that the most active extracts against HIV-1 PR, C. andromeda and G. filamentosa showed no cytotoxicity in the three cell lines at the highest concentration tested (100 μg/ml). CONCLUSION: The strong cytotoxicity of the soft corals L. arboreum and S. trochliophorum as well as the anti-PR activity of the jelly fish C. andromeda and the red algae G. filamentosa suggests the medicinal potential of crude extracts of these marine organisms.The Medical Research Council, the Technology Innovation Agency and the University of Pretoria, South Africa.http://www.biomedcentral.com/bmccomplementalternmedam201