Effects of Flower Acmella uliginosa (Swartz) Cass. on a Human Breast Cancer MCF-7 Cell Line and its Correlation with Metabolites Composition- GCMS based Metabolomics Approach.

Introduction: In-vitro cytotoxicity screening is a useful tool for the discovery of new potential anticancer agents from natural products. Acmella uliginosa (Swartz) Cassini; locally known as 'Pokok Getang' or 'Subang Nenek' has been used to relieve pain associated with toothaches. Methods: The present study investigated the correlation between untargeted metabolites and cytotoxicity effects of methanol crude of A. uliginosa flower on human breast cancer MCF-7 cells. All metabolites were determined by Gas Chromatography Mass Spectrometry (GCMS) analyses and the resulting chromatograms were exported to R version 2.13.0 (2011-04-13) software for peak selection. The relationships among the metabolites and cytotoxicity effects were evaluated using Orthogonal Projection to Latent Structure-Discriminant Analysis (OPLSDA) models in SIMCA13 software. Results: The GCMS data revealed the alkylamides were the major compounds in A. uliginosa flower. The inhibitory concentrations (IC50) of flower crude extract were 72.7µg/ml and 62.9µg/ml at 48 and 72 hours of treatment, respectively. The OPLS-DA model successfully discriminated the metabolites contributing to the cytotoxicity effects which both alkylamides; N-isobutyl-2(E),6(Z),8(E)-decatrienamide and N-isobutyl-2E,4Z,8Z,10E-dodecatetraenamide were identified attributing significantly to cytotoxicity effects on human breast cancer MCF-7 cell line. Alkylamides are known to have inhibition activities towards cyclooxygenase-1 and -2 (COX-1 and COX-2) and 5lipooxygenase that contribute to cancer and metastasis development. Conclusion: The proposed method of using multivariate data analysis to evaluate GCMS chromatograms in combination with cytotoxicity effects was successfully applied to identify active biomarkers. [ABSTRACT FROM AUTHOR]