Diphenyl Difluoroketone: A Potent Chemotherapy Candidate for Human Hepatocellular Carcinoma

Diphenyl difluoroketone (EF24), a molecule having structural similarity to curcumin, was recently reported to inhibit proliferation of various cancer cells significantly. Here we try to determine the effect and mechanism of EF24 on hepatocellular carcinoma. 2 µM EF24 was found to inhibit the proliferation of PLC/PRF/5, Hep3B, HepG2, SK-HEP-1 and Huh 7 cell lines. However, even 8 µM EF24 treatment did not affect the proliferation of normal liver LO2 cells. Accordingly, 20 mg/kg/d EF24 inhibited the growth of the tumor xenografts conspicuously while causing no apparent change in liver, spleen or body weight. In addition, significant apoptosis and G2/M phase cell cycle arrest were found using flow cytometry. Besides, caspases and PARP activation and features typical of apoptosis including fragmented nuclei with condensed chromatin were also observed. Furthermore, the mechanism was targeted at the reduction of nuclear factor kappa b (NF-κB) pathway and the NF-κB–regulated gene products Bcl-2, COX-2, Cyclin B1. Our study has offered a strategy that EF24 being a therapeutic agent for hepatocellular carcinoma

Microwave-assisted hydrolysis and extraction of tricyclic antidepressants from human hair

The objective of this research was to develop, optimize, and validate a modern, rapid method of preparation of human hair samples, using microwave irradiation, for analysis of eight tricyclic antidepressants (TCADs): nordoxepin, nortriptyline, imipramine, amitriptyline, doxepin, desipramine, clomipramine, and norclomipramine. It was based on simultaneous alkaline hair microwave-assisted hydrolysis and microwave-assisted extraction (MAH–MAE). Extracts were analyzed by high-performance liquid chromatography with diode-array detection (HPLC–DAD). A mixture of n-hexane and isoamyl alcohol (99:1, v/v) was used as extraction solvent and the process was performed at 60°C. Application of 1.0 mol L−1 NaOH and microwave irradiation for 40 min were found to be optimum for hair samples. Limits of detection ranged from 0.3 to 1.2 μg g−1 and LOQ from 0.9 to 4.0 μg g−1 for the different drugs. This enabled us to quantify them in hair samples within average therapeutic concentration ranges

Induction of apoptosis by the adenosine derivative IB-MECA in parental or multidrug-resistant HL-60 leukemia cells: possibile relationship to the effects on inhibitor of apoptosis protein levels

Background: The effects of the A3 adenosine receptor (A3AR) agonist lB-MECA were examined in HL-60 leukemia and in its multidrug-resistant variant HL60R cells. Methods: Cytotoxicity was evaluated by MTS assays and apoptosis by flow cytometry analyses of DNA fragmentation and phosphatidylserine exposure. The mRNAs of A3AR and inhlbitor of apoptosis proteins (lAPs) were determined by RT-PCR. Results: A3AR expression was similar in HL-60 and HL-60R cells. At 65 100 \u3bcM, IB-MECA exhibited strong cytotoxic and apoptotic effects in HL-60, but not in HL-60R cells. This activity was not modified by the A3AR antagonis VUF5574, the P-glycoprotein inhibitor verapamil, the adenosine uptake inhibitor NBTI or the anti Fas antibody Z B4, HL-60R cells showed higher levels of different IAPs than H L-60 cells. lB-MECA 100 \u3bcM downregulated HlAP1, NAIP and survivin mRNAs in HL-60, but not in HL-60R cells. Conclusions: The antitumor effects of IB-MECA are not mediated by A3AR in HL-60 cells, where the proapoptotic mechanism of the compound may involve downregulation of lAPs. The resistance of HL-60R cells to lB-MECA may depend on their elevated levels of lAPs