Synthetic Curcumin Derivative DK1 Possessed G2/M Arrest and Induced Apoptosis Through Accumulation of Intracellular ROS in MCF-7 Breast Cancer Cells

Curcumin is a lead compound of the rhizomes of Curcuma longa and possess a broad range of pharmacological activities. Chemically, curcumin is 1,3-dicarbonyl class of compound, which exhibits keto-enol tautomerism. Despite of its strong biological properties, curcumin has yet been recommended as a therapeutic agent because of its poor bioavailability. A curcumin derivative (Z)-3-hydroxy-1-(2-hydroxyphenyl)-3-phenylprop-2-en-1-one (DK1) was synthesized and its cytotoxicity was tested on breast cancer cell MCF-7 and normal cell MCF-10A using MTT assay. Meanwhile, cell cycle regulation and apoptosis on MCF-7 cell were evaluated using flow cytometry. Regulation of cell cycle and apoptosis related genes expression was investigated by quantitative real time polymerase chain reaction (qRT-PCR), western blot and caspases activity analyses. Activation of oxidative stress on MCF-7 were evaluated by measuring ROS and GSH levels

Combination of cisplatin and bromelain exerts synergistic cytotoxic effects against breast cancer cell line MDA-MB-231 in vitro

Background: Bromelain, which is a cysteine endopeptidase commonly found in pineapple stems, has been investigated as a potential anti-cancer agent for the treatment of breast cancer. However, information pertaining to the effects of combining bromelain with existing chemotherapeutic drugs remains scarce. This study aimed to investigate the possible synergistic cytotoxic effects of using bromelain in combination with cisplatin on MDA-MB-231 human breast cancer cells. Method: MDA-MB-231 cells were treated with different concentrations (0.24–9.5 µM) of bromelain or cisplatin alone, as well as four different combinations of these two agents to assess their individual and combination effects after 24 and 48 h. Cell viability was analyzed using an MTT assay. The induction of apoptosis was assessed using cell cycle analysis and an Annexin V-FITC assay. The role of the mitochondrial membrane potential in the apoptotic process was assessed using a JC-1 staining assay. Apoptotic protein levels were assessed by western blot analysis and proteome profiling using an antibody array kit. Results: Single-agent treatment with cisplatin or bromelain led to dose- and time-dependent decreases in the viability of the MDA-MB-231 cells at 24 and 48 h. Furthermore, most of the combinations evaluated in this study displayed synergistic effects against MDA-MB-231 cells at 48 h, with combination 1 (bromelain 2 µM + cisplatin 1.5 µM) exhibiting the greatest synergistic effect (P = 0.000). The results of subsequent assays indicated that combination 1 treatment induced apoptosis via mitochondria-mediated pathway. Combination 1 also resulted in significant decreases in the levels of several apoptotic proteins such as Bcl-x and HSP70, compared with bromelain (P = 0.002 and 0.000, respectively) or cisplatin (P = 0.000 and 0.001, respectively) single treatment. Notably, MDA-MB-231 cells treated with combination 1 showed increased levels of the pro-apoptotic proteins Bax compared with those treated with bromelain (P = 0.000) or cisplatin single treatment (P = 0.043). Conclusion: Bromelain in combination with cisplatin synergistically enhanced the induction of apoptosis in MDA-MB-231 cells

Synthetic curcumin derivative DK1 possessed G2/M arrest and induced apoptosis through accumulation of intracellular ROS in MCF-7 breast cancer cells

Aims: Curcumin is a lead compound of the rhizomes of Curcuma longa and possess a broad range of pharmacological activities. Chemically, curcumin is 1,3-dicarbonyl class of compound, which exhibits keto-enol tautomerism. Despite of its strong biological properties, curcumin has yet been recommended as a therapeutic agent because of its poor bioavailability. Main methods: A curcumin derivative (Z)-3-hydroxy-1-(2-hydroxyphenyl)-3-phenylprop-2-en-1-one (DK1) was synthesized and its cytotoxicity was tested on breast cancer cell MCF-7 and normal cell MCF-10A using MTT assay. Meanwhile, cell cycle regulation and apoptosis on MCF-7 cell were evaluated using flow cytometry. Regulation of cell cycle and apoptosis related genes expression was investigated by quantitative real time polymerase chain reaction (qRT-PCR), western blot and caspases activity analyses. Activation of oxidative stress on MCF-7 were evaluated by measuring ROS and GSH levels. Key findings: DK1 was found to possess selective cytotoxicity on breast cancer MCF-7 cell than normal MCF-10A cell. Flow cytometry cell cycle and AnnexinV/PI analyses reported that DK1 effectively arrested MCF-7 at G2/M phase and induced apoptosis after 72 h of incubation than curcumin. Upregulation of p53, p21 and downregulation of PLK-1 subsequently promote phosphorylation of CDC2 which were found contributed to the arrest of G2/M phase. Moreover, increased of reactive oxygen species and reduced of antioxidant glutathione level correlate with apoptosis observed with raised of cytochrome c and active caspase 9. Significance: DK1 was found to be more effective in inducing cell cycle arrest and apoptosis against MCF-7 cell with much higher selectivity index of MCF-10A/MCF-7 than curcumin, which might be contributed by the overexpression of p53 protein