Cytokinetics study and microarray analysis on mcf-7 cells treated with tomato leaves extract

Abstract

Nowadays, it is believed that cancer is one of the leading causes of death. Various types of drugs have been used. However some of them may give side effects to human health. Therefore, this research aimed to study the potentiality of tomato leaves extract as anti-cancer agent by studying the growth kinetics behavior of MCF-7 breast cancer cells after treated with the extract and analyzed the affected genes by microarray analysis. The extraction was carried out in a shake flask using 82% methanol, 1:10 (w/v), agitated at 110 rpm in 22°C for 24 hours. Chromatography techniques were used to isolate the active fractions from the extract. The effect of the isolated active fractions from tomato leaves extract (TLE) on MCF-7 breast cancer cells and Vero cells (non-cancerous cells) were observed by anti-proliferative test using SRB assay. The assay was used to indicate the TLE half maximal inhibitory concentration (IC50). Later, phytochemical screening was carried out to identify the secondary metabolites. The effects of TLE on MCF-7 breast cancer cells were further scrutinized by cytokinetics study associated with microarray analysis to forecast it ability in eradicating the growth of cancer cells. TLE gave a rational effect on MCF-7 breast cancer cells with IC50 value of 5.85 ?g/mL and it also can be judged to be harmless as it had IC50 value of 765.6 ?g/mL in non-cancerous cells. In phytochemical screening, TLE showed a presence of flavonoid that could be responsible for the anti-proliferative activity. Furthermore, the growth kinetics study indicated that TLE inhibited the cell growth with number of cell generations reduced from 3.92 generations to 3.35 generations. TLE had also affected the growth rate with dynamical decrement from 0.021 h-1 to 0.016 h-1 and the doubling time expanded from 14.3 hours to 18.8 hours. Moreover, the death rate increased to 0.009 h-1 as compared to untreated MCF-7 cells which only declined at a rate of 0.005 h-1. The results of the microarray analysis revealed several genes differentially expressed by MCF-7 cells following 1 hour and 48 hours of TLE treatment. The affected genes were BTG1, HIST2H3D, CRYAB and CYR61, involves in cell cycle regulation related to cancer progression, TXNIP, CEBP? and HMG1L1, involves in regulation of transcriptional and DNA binding activator, and lastly, THBS1, HIF1A and PIM1 genes, involves in p53 signaling pathway, mTOR signaling pathway and JAK-STAT pathway, respectively. In conclusion, TLE can be one of the promising anti-cancer agents which are safe and effective.