Combination of Salermide and Cholera Toxin B Induce Apoptosis in MCF-7 but Not in MRC-5 Cell Lines.
BACKGROUND
Sirtuin1 is an enzyme that deacetylates histones and several non-histone proteins including P53 during the stress. P300 is a member of the histone acetyl transferase family and enzyme that acetylates histones. Hereby, this study describes the potency combination of Salermide as a Sirtuin1 inhibitor and cholera toxin B (CTB) as a P300 activator to induce apoptosis Michigan Cancer Foundation-7 (MCF-7) and MRC-5.


METHODS
Cells were cultured and treated with a combination of Salermide and CTB respectively at concentrations of 80.56 and 85.43 μmol/L based on inhibitory concentration 50 indexes at different times. The percentage of apoptotic cells were measured by flow cytometry. Real-time polymerase chain reaction was performed to estimate the messenger ribonucleic acid expression of Sirtuin1 and P300 in cells. Enzyme linked immunosorbent assay and Bradford protein techniques were used to detect the endogenous levels of total and acetylated P53 protein generated in both cell lines.


RESULTS
Our findings indicated that the combination of two drugs could effectively induced apoptosis in MCF-7 significantly higher than MRC-5. We showed that expression of Sirtuin1 and P300 was dramatically down-regulated with increasing time by the combination of Salermide and CTB treatment in MCF-7, but not MRC-5. The acetylated and total P53 protein levels were increased more in MCF-7 than MRC-5 with incubated combination of drugs at different times. Combination of CTB and Salermide in 72 h through decreasing expression of Sirtuin1 and P300 genes induced acetylation of P53 protein and consequently showed the most apoptosis in MCF-7 cells, but it could be well-tolerated in MRC-5.


CONCLUSIONS
Therefore, combination of drugs could be used as an anticancer agent.
Fertility and Infertility Research Center, Medical School, Kermanshah University of Medical Sciences, Kermanshah, Iran.
Mohammad Reza
MR
Salahshoor
Department of Anatomical Sciences and Molecular Biology, Medical School, Isfahan University of Medical Sciences, Isfahan, Iran.
Mehdi Nikbakht
MN
Dastjerdi
Department of Anatomical Sciences and Molecular Biology, Medical School, Isfahan University of Medical Sciences, Isfahan, Iran.
Cyrus
C
Jalili
Department of Anatomical Sciences and Molecular Biology, Medical School, Isfahan University of Medical Sciences, Isfahan, Iran.
Mohammad
M
Mardani
Fertility and Infertility Research Center, Medical School, Kermanshah University of Medical Sciences, Kermanshah, Iran.
Mozafar
M
Khazaei
Department of Anatomical Sciences and Molecular Biology, Medical School, Rafsanjan University of Medical Sciences, Rafsanjan, Iran.
Ahmad Shabanizadeh
AS
Darehdor
Fertility and Infertility Research Center, Medical School, Kermanshah University of Medical Sciences, Kermanshah, Iran.
Ali
A
Valiani
Fertility and Infertility Research Center, Medical School, Kermanshah University of Medical Sciences, Kermanshah, Iran.
Shiva
S
Roshankhah
Apoptosis; MRC-5; Michigan Cancer Foundation-7; Salermide; cholera toxin B