P6.04 - Application of Biosurfactants in Cancer Therapy

Abstract

ABSTRACT Introduction: Microbial biosurfactants (BSs) are amphiphilic compounds that exist as families of congeners and isomers which have been identified as possible anti-cancer agents. The aim of this study is to investigate the anticancer activity of BSs on breast and blood derived cancers. Materials and methods: Four biosurfactants (BSs) 95% rhamnolipid (BS1a), 90% rhamnolipid (BS1b), surfactin (BS2), sophorolipid (BS3) and a positive control Doxorubicin hydrochloride (DOX) were tested at concentrations ranging from 3.13-100 µg/ml and 1.25-25 µM for the BSs and DOX respectively. Cytotoxicity was obtained via MTT assay following cell line-specific optimization at intervals of 24, 48 and 72 hours from treatment on non-cancerous human embryo kidney (HEK 293), human caucasian breast adenocarcinoma (MCF7) and human leukaemia monocyte (THP-1) cell lines. Results: BS3 showed the greatest potency against all cell lines with IC50 of 18, 16 and 15 µg/ml at 24, 48 and 72 hours respectively against THP-1 cells and IC50 ranging between 20 and 30 µg/ml against HEK 293 and MCF7 after the same treatment times. The effect of BS2 and BS1b were variable with lower IC50 in cancerous cell lines at late stages of treatment (68 and 18 µg/ml for MCF7 and THP-1 at 72 hours treatment) when compared with IC50 of over 100 µg/ml in HEK 293. Finally BS1a showed no activity (IC50 > 100 µg/ml) against all cell lines tested independently from the incubation time used. Conclusion: Although BS1a and BS1b have almost identical mass spectra, BS1b showed a higher amount of potency. BS2 and BS1b showed considerable potential as possible therapeutic agents in breast and blood derived cancer research. Future work will investigate identification of the specific congeners/isomers responsible for the observed activities.