SUBJECT: DCA drug & MCF7 Breast cancer cell

DCA drug & MCF7 Breast cancer cell

DCA drug & MCF7 Breast cancer cell

Result and Discussion

[DCA]

expt 1

expt 2

expt 3

expt 4

mean

sem

P value (t-test)

0

0.601

0.501

0.579

0.889

0.645

0.085

1

0.749

0.515

0.643

0.922

0.707

0.086

0.611

10

0.718

0.519

0.57

1.111

0.73

0.134

0.603

100

0.677

0.553

0.454

1.126

0.703

0.149

0.701

1000

0.626

0.598

0.379

1.281

0.721

0.195

0.724

The above table shows that we need to accept our null hypothesis because the p values are greater than level of significance which is 0.05.

DCA reduces MCF-7 cancer cell viability in a

dose-dependent manner

To determine the effect of DCA on the viability of MCF-7 cancer cells, each cell line was grown in culture with increasing doses of DCA. In a panel of seven MCF-7 cancer cells lines, AN3CA, Ishikawa, RL95-2, and SKUT1B had a 15% - 75% decrease in viability with increasing DCA concentration (Fig. 1A). Reduction in viability formost of the responding cell lines reached significance at the 10 mM dose. A comparison between the untreated group and the 10 mM DCA-treated group had p-values b0.01 for AN3CA, Ishikawa, RL95-2, and SKUT1B. A marginally significant decrease in viability was seen at the 5mMdose for AN3CA and RL95-2. Therefore, an approximate effective minimal dose of DCA for these MCF-7 cell lines under the treatment periodwas determined to be between 5mMand 10mM. This DCA dose concentration and treatment time is within the effective range of previously published in vitro experiments . A statistically significant increase in viability was observed with HEC1A, HEC1B, and KLE with increasing DCA concentrations ( pb0.02). As expected, no statistically significant difference in viability was observed in the 293T epithelial cells at the given DCA dose range and treatment period ( p=0.27).

The effect of DCA on MCF-7 cancer cell proliferation is cell line-dependent

To determine whether the observed decrease in cell viability with DCA treatment was due to a cell proliferation effect, a BrdU/7-AAD staining was performed on several representative cell lines and analyzed via flow cytometry. No significant difference in cell cycle dynamics or proliferation was observed in Ishikawa, HEC1B, and 293T epithelial cells with DCA treatment (Table 1). In AN3CA, treatment with DCA increased proliferation, as indicated by significant increases in the number of cells in S and G2/M phases and fewer cells in G0/G1. In RL95-2 cells, treatment with DCA significantly decreased the proportion of cells in S and G2/M phases and increased cells in G0/G1 phase; indicating decreased proliferation and cell cycle arrest in either a senescent or quiescent state.

DCA promotes apoptosis in MCF-7 cancer cells

In order to determine whether the reduction of cell viability from DCA treatment was due to apoptosis rather than necrosis, an Annexin-V-FITC and 7-AAD cell staining was performed and analyzed using flow cytometry. Significant increases of 50% to 325% were observed in early apoptotic cells in AN3CA, Ishikawa, KLE, RL95-2 and SKUT1B (Fig. 1B). Significant increases were also observed in late apoptotic cells of these cell lines (Fig. 1B). RL95-2 had the greatest increase in early apoptotic cells, while KLE had the least significant increase. The increased percentage of late apoptotic cells in KLE was not statistically significant. There was no observed difference in the percentage of early and late apoptotic cells with ...