ABSTRACT
BACKGROUND: Breast cancer cells over-express the adenosine receptor A1 and in most of these cells, P53 gene is a wild type. Because of this finding and relationship between A1 receptor and cell apoptosis and proliferation, this study aimed to determine the effect of agonist and antagonist of A1 receptor on cell apoptosis and proliferation and recognize the relationship between this receptor and P53 expression. METHODS: We used a Real-Time PCR test for measuring expression of p53 gene also flow cytometry assay for apoptotic and survival cell rate after treatment of MCF-7 cells with A1 receptor agonist CPA (N6-Cyclopentyladenosine) and A1 receptor antagonist DPCPX (1,3-dipropyl-8-cyclopentylxanthine) in 24,48 and 72 hours. RESULTS: Our flow cytometry findings indicate that DPCPX significantly induces apoptosis in MCF-7. Also the expression of P53 becomes upregulated with time of DPCPX treatment. CPA treatment increased the survival cell rate and down-regulated this apoptosis-relevant gene P53 (p > 0.05). CONCLUSION: DPCPX can induce P53 expression which consequently promotes the cell apoptosis in MCF-7. Therefore, DPCPX could be used as an anti-cancer agent (Tab. 1, Fig. 3, Ref. 5).
Subject(s)
Adenosine/analogs & derivatives , Breast Neoplasms , Receptor, Adenosine A1/metabolism , Xanthines/pharmacology , Adenosine/pharmacology , Adenosine A1 Receptor Agonists/pharmacology , Adenosine A1 Receptor Antagonists/pharmacology , Apoptosis/drug effects , Cell Proliferation/drug effects , Cell Survival/drug effects , Gene Expression Profiling , Genes, p53/genetics , Humans , MCF-7 CellsABSTRACT
Pancreatic carcinoma is currently considered as a rapidly progressive and fatal disease, and is typically diagnosed late in its natural course. It is characterized by a poor diagnosis and lack of response to conventional therapy. Recent studies have suggested that disulfiram (DSF), a member of the dithiocarbamate family, may have antitumor activity. This study aimed to evaluate the in vitro effect of DSF on apoptosis in human pancreatic cancerous cell line (PANC-1). PANC-1 cells were cultured and treated with DSF at doses of 5, 10, 13 µM for 24 h and apoptosis was measured. Methylation specific PCR (MS-PCR) and real-time quantitative PCR were carried out to detect the methylation pattern and to estimate the mRNA expression levels of RASSF1A, p21 and Bax. MS-PCR analysis demonstrated that no unmethylated band was apeared in PANC-1 cell line after DSF treatments. The real-time quantitative PCR results showed no significant mRNA expression for RASSF1A (p>0.05); whereas p21 and Bax expression were significantly (p<0.01) enhanced after treatment with DSF. The results of the current study indicated that DSF can induce appoptosis in PANC-1 through p21 and Bax pathway but not through RASSF1A.
ABSTRACT
Sirtuin1 (SIRT1) is an enzyme that deacetylates histones and several nonhistone proteins including p53 during stress and plays an important role in the survival of tumor cells. Hereby, this study describes the potency of salermide as a SIRT1 inhibitor to induce apoptosis in the MCF-7 and MRC-5 cell lines. MCF7 and MRC-5 cell lines were cultured in RPMI-1640 and treated with or without salermide at concentration of 80.56 µmol/L, based on the half-maximal inhibitory concentration (IC50) index at different times (24, 48 and72 h). The IC50 value was established for the salermide in MCF-7. The percentage of apoptotic cells was measured by flow cytometry. Real-time quantitative RT-PCR was performed to estimate the mRNA expression of sirtuin1 in MCF-7 and MRC-5 with salermide at different times. ELISA and Bradford protein techniques were used to detect endogenous levels of total and acetylated p53 protein generated in MCF-7 and MRC-5 cells. Our findings indicated that salermide can induce apoptosis in MCF-7 significantly more effective than MRC-5 cells. We showed that the expression of SIRT1 was dramatically down-regulated by increasing the time of salermide treatment in MCF-7 but not MRC-5 and that the acetylated and total p53 protein levels were increased more in MCF-7 than MRC-5. Salermide, by decreasing the expression of sirtuin1 gene, can induce acetylation of P53 protein and consequently induce significant cell death in MCF-7 that was well tolerated in MRC-5.
