title: Screening for Anti-Cancer Compounds in Marine Organisms in Oman.
abstract: OBJECTIVE
  Marine organisms are a rich source of bioactive molecules with potential applications in medicine, biotechnology and industry; however, few bioactive compounds have been isolated from organisms inhabiting the Arabian Gulf and the Gulf of Oman. This study aimed to isolate and screen the anti-cancer activity of compounds and extracts from 40 natural products of marine organisms collected from the Gulf of Oman.
  
  
  METHODS
  This study was carried out between January 2012 and December 2014 at the Sultan Qaboos University, Muscat, Oman. Fungi, bacteria, sponges, algae, soft corals, tunicates, bryozoans, mangrove tree samples and sea cucumbers were collected from seawater at Marina Bandar Al-Rowdha and Bandar Al-Khayran in Oman. Bacteria and fungi were isolated using a marine broth and organisms were extracted with methanol and ethyl acetate. Compounds were identified from spectroscopic data. The anti-cancer activity of the compounds and extracts was tested in a Michigan Cancer Foundation (MCF)-7 cell line breast adenocarcinoma model.
  
  
  RESULTS
  Eight pure compounds and 32 extracts were investigated. Of these, 22.5% showed strong or medium anti-cancer activity, with malformin A, kuanoniamine D, hymenialdisine and gallic acid showing the greatest activity, as well as the soft coral Sarcophyton sp. extract. Treatment of MCF-7 cells at different concentrations of Sarcophyton sp. extracts indicated the induction of concentration-dependent cell death. Ultrastructural analysis highlighted the presence of nuclear fragmentation, membrane protrusion, blebbing and chromatic segregation at the nuclear membrane, which are typical characteristics of cell death by apoptosis induction.
  
  
  CONCLUSIONS
  Some Omani marine organisms showed high anti-cancer potential. The efficacy, specificity and molecular mechanisms of anti-cancer compounds from Omani marine organisms on various cancer models should be investigated in future in vitro and in vivo studies.
authors.affiliation: Department of Marine Science & Fisheries, College of Agricultural & Marine Sciences, Sultan Qaboos University;; Centre of Excellence in Marine Biotechnology, Sultan Qaboos University;
authors.forename: Sergey
authors.initials: S
authors.lastname: Dobretsov
authors.affiliation: Departments of Biochemistry, Sultan Qaboos University;
authors.forename: Yahya
authors.initials: Y
authors.lastname: Tamimi
authors.affiliation: Pathology, College of Medicine & Health Sciences, Sultan Qaboos University;
authors.forename: Mohamed A
authors.initials: MA
authors.lastname: Al-Kindi
authors.affiliation: Department of Medicine, Sultan Qaboos University Hospital, Muscat, Oman.
authors.forename: Ikram
authors.initials: I
authors.lastname: Burney
keywords: Anticancer Agents; Apoptosis; Biological Products; Breast Cancer; Cancer Screening; Marine Organisms; Oman