Gut Bacteria of Columbia livia Are a Potential Source of Anti-Tumour Molecules.

OBJECTIVES: The overall aim was to determine whether gut bacteria of Columbia livia are a potential source of antitumour molecules. METHODS: Faecal and gut microbiota of Columbia livia were isolated, identified and conditioned media were prepared containing metabolites. Growth inhibition, lactate dehydrogenase cytotoxicity and cell survival assays were accomplished against cervical cancer cells. Next, liquid-chromatography mass spectrometry was conducted to elucidate the molecules present. RESULTS: A plethora of bacteria from faecal matter and gastrointestinal tract were isolated. Selected conditioned media exhibited potent anticancer effects and displayed cytotoxicity to cervical cancer cells at IC50 concentration of 10.65 and 15.19 µg/ml. Moreover, cells treated with conditioned media exhibited morphological changes, including cell shrinking and rounding; indicative of apoptosis, when compared to untreated cells. A total of 111 and 71 molecules were revealed from these gut and faecal metabolites. The identity of 60 molecules were revealed including, dihydroxymelphalan. Nonetheless, 122 molecules remain unidentified and are the subject of future studies. CONCLUSION: These findings suggest that gut bacteria of Columbia livia possess molecules, which may have anticancer activities. Further in silico testing and/or high throughput screening will determine potential anticancer properties of these molecules.
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1-O-alkylglycerols from the hepatopancreas of the crab Paralithodes camtschaticus, liver of the squid Berryteuthis magister, and liver of the skate Bathyraja parmifera, and their anticancer activity on human melanoma cells.

1-O-alkylglycerols (AKG) are a class of natural ether lipids derived from 1-O-alkyl-2,3-diacyl-sn-glycerols by deacylation. In this study, 1-O-alkylglycerol (AKG) composition was investigated in the hepatopancreas lipids of the crab Paralithodes camtschaticus and the liver lipids of the squid Berryteuthis magister and the skate  Bathyraja parmifera. One of the principal AKG in marine organisms was 1-O-hexadecyl-sn-glycerol (AKG 16:0). To assess AKG influence on melanoma, we evaluated the cytotoxicity and antiproliferative actions of natural AKG 16:0 and synthetic 1-O-octyl-sn-glycerol (AKG 8:0) on three human melanoma cell lines SK-Mel-5, SK-Mel-28, and RPMI-7951. Natural AKG 16:0 in concentration up to 20 µM was not toxic to all cell lines. AKG 8:0 showed no toxicity to cells SK-Mel-5 and SK-Mel-28 in concentrations up to 20 µM but had moderate cytotoxicity to RPMI-7951 cells with an IC50 of 13 µM. Both investigated substances inhibited the proliferation, formation, and growth of cell colonies of RPMI-7951. PRACTICAL APPLICATIONS: AKG exhibit a variety of biological activities, including anticancer effects. In this study, the liver lipids of the skate B. parmifera and the hepatopancreas lipids of crab P. camtschaticus were shown to be sources of AKG. Our data showed that AKG can be used to prevent the formation of new colonies of malignant cells in combination therapy against melanoma. The results will be useful for future studies involving marine ether lipids and the examination of their anticancer properties against malignant cells.

Separation and identification of trinucleotide-melphalan adducts from enzymatically digested DNA using HPLC-ESI-MS.

Melphalan is a bifunctional alkylating agent that covalently binds to the nucleophilic sites present in DNA. In this study we investigated oligonucleotides prepared enzymatically from DNA modified with melphalan. Calf thymus DNA was incubated in-vitro with melphalan and the resulting modifications were enzymatically cleaved by means of benzonase and nuclease S1. Efficient sample preconcentration was achieved by solid-phase extraction, in which phenyl phase cartridges resulted in better recovery of the modified species than C(18). The applied enzymatic digestion time resulted in production of trinucleotide adducts which were efficiently separated and detected by use of reversed-phase HPLC coupled to an ion-trap mass spectrometer with electrospray ionization. It was assumed that melphalan could act as both a monofunctional and bifunctional alkylating agent. Mono-alkylated adducts were much more abundant, however, and the alkylation site was located on the nucleobases. On the other hand, we unequivocally identified cross-link formation in DNA, even though at low abundance and only a few adduct types were detected.