Comparative effect of sodium butyrate and sodium propionate on proliferation, cell cycle and apoptosis in human breast cancer cells MCF-7.

INTRODUCTION: Short-chain fatty acids (SCFAs) are ubiquitous lipids produced as a result of bacterial fermentation of dietary fiber. While their role in colorectal cancer is well known, the effect of SCFAs in breast cancer is poorly defined. OBJECTIVE: To understand the various effects of SCFAs on breast carcinogenesis, we investigated the effect of sodium butyrate (NaB) and sodium propionate (NaP) in MCF-7 cell line. MATERIALS AND METHODS: Cells were incubated with different concentrations of NaB or NaP for 24, 48, 72 or 96 h. Cell proliferation was assayed using MTT kit. Cell cycle was performed using propidium iodide staining then analyzed with a flow cytometer. Apoptosis was assessed by Hoechst technique and cell-cycle sub-G1 phase. RESULTS: NaB and NaP inhibited MCF-7 cell proliferation in a dose-dependent manner with respective IC50 of 1.26 mM and 4.5 mM, thus indicating that NaB is more potent than NaP. Low and medium levels of both SCFAs induced morphology changes which are characteristic of a differentiated phenotype. Flow cytometry analysis revealed a blockage in G1 growth phase. Interestingly, removing NaB or NaP from culture media after few days of treatment showed a reversible effect on cell morphology and proliferation where cells reentered the cycle after 24 h of drug wash-out. Finally, treatment with medium levels of these molecules induced low MCF-7 apoptosis, while higher doses led to massive apoptosis. CONCLUSION: Our results show that SCFAs may be considered as an interesting inhibitor for breast cancer progression.

Inhibition of Proliferation and Induction of Apoptosis by Thymoquinone via Modulation of TGF Family, p53, p21 and Bcl-2α in Leukemic Cells.

INTRODUCTION: Adult T-cell leukemia (ATL) is an aggressive form of malignancy caused by human T- cell lymphotropic virus 1 (HTLV-1). Currently, there is no effective treatment for ATL. Thymoquinone has been reported to have anti-cancer properties. OBJECTIVE: The aim of this study is to investigatthe effects of TQ on proliferation, apoptosis induction and the underlying mechanism of action in both HTLV-1 positive (C91-PL and HuT-102) and HTLV-1 negative (CEM and Jurkat) malignant T-lymphocytes. MATERIALS AND METHODS: Cells were incubated with different thymoquinone concentrations for 24h. Cell cytotoxicity was assayed using the CytoTox 96® Non-Radioactive Cytotoxicity Assay Kit. Cell proliferation was determined using CellTiter 96® Non-Radioactive Cell Proliferation. Cell cycle analysis was performed by staining with propidium iodide. Apoptosis was assessed using cell death ELISA kit. The effect of TQ on p53, p21, Bcl-2 protein expression was determined using Western blot analysis while TGF mRNA expression was determined by RT-PCR. RESULTS: At non-cytotoxic concentrations of TQ, it resulted in the inhibition of proliferation in a dose dependent manner. Flow cytometric analysis revealed a shift in the cell cycle distribution to the PreG1 phase which is a marker of apoptosis. Also TQ increase DNA fragmentation. TQ mediated its anti-proliferative effect and apoptosis induction by an up-regulation of TGFß1, p53 and p21 and a down-regulation of TGF-α and Bcl-2α. CONCLUSION: Thymoquinone presents antiproliferative and proapoptotic effects in ATL cells. For this reason, further research is required to investigate its possible application in the treatment of ATL.

Design and multi-step synthesis of chalcone-polyamine conjugates as potent antiproliferative agents.

The aim of this study is to synthesize chalcone-polyamine conjugates in order to enhance bioavailability and selectivity of chalcone core towards cancer cells, using polyamine-based vectors. 3-hydroxy-3',4,4',5'-tetramethoxychalcone (1) and 3',4,4',5'-tetramethoxychalcone (2) were selected as parent chalcones since they were found to be efficient anti-proliferative agents on various cancer cells. A series of ten chalcone-polyamine conjugates was obtained by reacting carboxychalcones with different polyamine tails. Chalcones 1 and 2 showed a strong cytotoxic activity against two prostatic cancer (PC-3 and DU-145) and two colorectal cancer (HT-29 and HCT-116) cell lines. Then, chalcone-spermine conjugates 7d and 8d were shown to be the most active of the series and could be considered as promising compounds for colon and prostatic cancer adjuvant therapy.

Resistance to 3-HTMC-Induced Apoptosis Through Activation of PI3K/Akt, MEK/ERK, and p38/COX-2/PGE2 Pathways in Human HT-29 and HCT116 Colorectal Cancer Cells.

Increasing incidence and mortality of colorectal cancer brings the necessity to uncover new possibilities in its prevention and treatment. Chalcones have been identified as interesting compounds having chemopreventive and antitumor properties. In this study, we investigated the effects of the synthetic chalcone derivative 3-hydroxy-3',4,4',5'-tetra-methoxy-chalcone (3-HTMC) on proliferation, cell cycle distribution, apoptosis, and its mechanism of action in human colorectal HT-29 (COX-2 sufficient) and HCT116 (COX-2 deficient) cancer cells. We showed that 3-HTMC decreased cell viability in a dose-dependent manner with a more potent antiproliferative effect on HCT116 than HT-29 cells. Flow cytometric analysis revealed G2 /M cell cycle accumulation in HT-29 cells and significant G2 /M arrest in HCT116 cells with a subsequent apoptosis shown by appearance of Sub-G1 peak. We demonstrated that 3-HTMC treatment on both cell lines induced apoptotic process associated with overexpression of death receptor DR5, activation of caspase-8 and -3, PARP cleavage, and DNA fragmentation. In addition, 3-HTMC induced activation of PI3K/Akt and MEK/ERK principal survival pathways which delay 3-HTMC-induced apoptosis in both cell lines. Furthermore, COX-2 overexpression in HT-29 cells contributes to apoptosis resistance which explains the difference of sensitivity between HT-29 and HCT116 cells to 3-HTMC treatment. Even if resistance mechanisms to apoptosis reduced chalcone antitumoral potential, our results suggest that 3-HTMC may be considered as an interesting compound for colorectal cancer therapy or chemoprevention. J. Cell. Biochem. 117: 2875-2885, 2016. © 2016 Wiley Periodicals, Inc.