Econazole Nitrate Induces Apoptosis in MCF-7 Cells via Mitochondrial and Caspase Pathways.

Econazole nitrate (EN), a synthetic compound, is now in use as a routine antifungal drug. EN was shown to have antitumor effect, the tumor cell killing mechanisms, however, remain unclear. In this research, the apoptosis-inducing effect of EN on MCF-7 cells was investigated. The results showed that EN inhibited the proliferation of MCF-7 cells in a time- and dose-dependent manner by MTT method and colony forming assay. MCF-7 cells treated with EN showed typical characteristics of apoptosis including the morphological changes and DNA fragmentation. Meanwhile, the loss of mitochondrial membrane potential was showed by flow cytometry. In addition, western blot analysis showed that EN resulted in the decrease expression of procaspase-3, procaspase-9 and bcl-2. In conclusion, these findings suggest that EN may be an effective way for treating human breast cancer. The anti-tumor mechanisms of EN might involve mitochondrial and caspase pathways.

Voltammetric behavior of the MCF-7 cell cytoplasm and the effect of taxol on voltammetric response.

The aims of this study were to find the electroactive species in the human breast cancer (MCF-7) cell cytoplasm causing a voltammetric response of the cells and to establish a simple and rapid measurement method to obtain strong and direct electrochemical responses objectively reflecting the cell viability. Ultrasonication was carried out for the electrochemical detection. The presence of guanine and xanthine in the MCF-7 cell eluent secreted by the living cells and in the MCF-7 cell cytoplasm was verified by HPLC assay with a DAD system and chemometric method. The concentrations of guanine and xanthine in the MCF-7 cell cytoplasm and the voltammetric response of the MCF-7 cell cytoplasm had higher levels than those of intact cell suspensions. Additionally, taxol caused a decrease of the voltammetric response of the cytoplasm and concentrations of xanthine and guanine in the cytoplasm. Therefore, the origin of the voltammetric response of the MCF-7 cytoplasm was driven by the alteration of the levels of xanthine and guanine, which were related to the cell viability. Thus, the voltammetric response of the ultrasonicated MCF-7 cell suspension could be used to monitor the MCF-7 cell growth and to evaluate the effectiveness of antitumor drugs on tumor suppression.

Determination of a hydrophilic paclitaxel derivative, 7-xylosyl-10-deacetylpaclitaxel in rat plasma by LC-MS/MS.

A LC-MS/MS method for the determination of a hydrophilic paclitaxel derivative 7-xylosyl-10-deacetylpaclitaxel in rat plasma was developed to evaluate the pharmacokinetics of 7-xylosyl-10-deacetylpaclitaxel in the rats. 7-Xylosyl-10-deacetylpaclitaxel and docetaxel (IS for 7-xylosyl-10-deacetylpaclitaxel) were extracted from rat plasma with acetic ether and analyzed on a Hypersil C(18 )column (4.6 x 150 mm i.d., particle size 5 microm) with the mobile phase of ACN/0.05% formic acid (50:50, v/v). The analytes were detected using an ESI MS/MS in the multiple reaction monitoring mode. The standard curves for 7-xylosyl-10-deacetylpaclitaxel in plasma were linear (r > 0.999) over the concentration range of 2.0-1000 ng/mL with a weighting of 1/concentration(2). The method showed a satisfactory sensitivity (2.0 ng/mL using 50 microL plasma), precision (CV

Anti-proliferative and pro-apoptotic effect of CPT13, a novel camptothecin analog, on human colon cancer HCT8 cell line.

10-(2-pyrazolyl-ethoxy)-(20S)-camptothecin (CPT13) is a novel semi-synthetic analogue of camptothecin, our previous report had shown that it possessed higher in vitro cytoxicity activity towards human colon cancer HCT8 cell line than topotecan. In this study, the anti-proliferative effect of CPT13 on HCT8 cell line in vitro was analyzed. In order to further explore the underlying mechanism of cell growth inhibition of CPT13 towards HCT8 cell line, the cell cycle distribution, apoptosis proportion, the nuclei morphological changes and caspase-8 and caspase-3 activities were measured. Additionally the changes of mitochondrial morphology and membrane potential (DeltaPsim) were analyzed by atomic force microscopy (AFM) and flow cytometry, respectively. The results showed that CPT13 inhibited HCT8 cell growth by causing cell cycle arrest at G2/M transition and induced apoptosis, as evidenced by the typical apoptotic morphology such as condensation and fragmentation of nuclei and formation of apoptotic bodies. The changes of mitochondrial morphology, dose-dependently decrease in DeltaPsim and the enhancement of caspase-8 and caspase-3 activities were observed in different concentrations of drug treatment group. Our results suggest that CPT13 induces apoptosis by alternations of mitochondrial transmembrane depolarization, activation of caspase-8 and caspase-3. Therefore, CPT13 appears to be a potent drug against human colon cancer via induction of apoptosis and may be used as an alternative drug to therapy cancer.