Up-Regulation of Bax/BCL-2 Ratio by 2-Methoxyestradiol Induces Apoptosis in Lymphoma Raji Cells / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of 2-methoxyestradiol (2-ME2) to lymphoma Raji cells and its mechanism.@*METHODS@#Different concentrations of 2-ME2 were used to treat lymphoma Raji cells. CCK8 method was used to detect the effect of 2-ME2 to proliferation of Raji cells. Flow cytometry FITC/PI double labeling method was used to detect early apoptosis of the cells. Western blotting was used to detect the effect of 2-ME2 to the expression of BCL-2, Bax, Caspase-3 and C-myc proteins in Raji cells.@*RESULTS@#2-ME2 significantly inhibited the proliferation of Raji cells. The inhibition rate increased with the increasing of drug concentration, and increased significantly with the prolongation of drug treatment time (r=0.9215). Flow cytometry FITC/PI double staining showed that the apoptotic rate of 2.5 μmol/L 2-ME2 treatment group was (33.79±1.63) %, while the apoptosis rate of the 48 h group was (51.90±2.72) %, and that of the control group was (7.08±0.36) %. After treated with 2.5 μmol/L 2-ME2 for 12 h, the expression of Bax protein was up-regulated, BCL-2 protein was down-regulated, caspase-3 protein expression was up-regulated, and C-myc protein expression was down-regulated, all of them showed a time-dependent relationship.@*CONCLUSION@#2-ME2 shows obvious inhibitory effect on lymphoma Raji cells in a dose- and time-dependent manner. Its mechanism of treatment on lymphoma Raji cells may be related to up-regulation of Bax/BCL-2 ratio and activation of Caspase-3 to induce apoptosis in cancer cells. Down-regulation of C-myc protein expression also participates in the apoptotic process.

Preparation and evaluation of 2-methoxyestradiol-loaded pH-sensitive liposomes

The development and clinical application of 2-methoxyestradiol (2-ME) as a new type of antitumor drug are limited due to its poor solubility, rapid metabolism in vivo, and large oral dosage. 2-ME-loaded pH-sensitive liposomes (2-ME-PSLs) was prepared containing the lipids, Lipoid E-80 (E-80), cholesteryl hemisuccinate (CHEMS), and cholesterol (CHOL) via thin-film ultrasonic dispersion. First, preparation conditions of 2-ME-PSLs were optimized by orthogonal test. Then 2-ME-PSL was characterized, and the release behavior and stability of 2-ME-PSL in vitro were evaluated. The optimal preparation conditions for 2-ME-PSLs were as follows: 2-ME : E-80+CHEMS 1:15; CHOL : E-80+CHEMS 1:5; ultrasonication time 20 minutes. The mean particle size, PDI, zeta potential, and entrapment efficiency (EE) of 2-ME-PSLs were 116 ± 9 nm, 0.161 ± 0.025, −22.4 ± 1.7 mV, and 98.6 ± 0.5%, respectively. As viewed under a transmission electron microscope, 2-ME-PSLs were well dispersed and almost spherical. They exhibited significant pH-sensitive properties and were fairly stable when diluted with a physiological solution. In conclusion, 2-ME-PSLs were successfully prepared and possessed a favorable pH sensitivity and good dissolution stability with a normal solution

In vitro assessment of a computer-designed potential anticancer agent in cervical cancer cells

BACKGROUND: Computer-based technology is becoming increasingly essential in biological research where drug discovery programs start with the identification of suitable drug targets. 2-Methoxyestradiol (2ME2) is a 17ß-estradiol metabolite that induces apoptosis in various cancer cell lines including cervical cancer, breast cancer and multiple myeloma. Owing to 2ME2's poor in vivo bioavailability, our laboratory in silico-designed and subsequently synthesized a novel 2ME2 analogue, 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10),15-tetraen-17-ol (ESE-15-ol), using receptor- and ligand molecular modeling. In this study, the biological effects of ESE-15-ol (180 nM) and its parent molecule, 2ME2 (1 µM), were assessed on morphology and apoptosis induction in cervical cancer cells. RESULTS: Transmission electron microscopy, scanning electron microscopy and polarization-optical transmitted light differential interference contrast (PlasDIC) images demonstrated morphological hallmarks of apoptosis including apoptotic bodies, shrunken cells, vacuoles, reduced cell density and cell debris. Flow cytometry analysis showed apoptosis induction by means of annexin V-FITC staining. Cell cycle analysis showed that ESE-15-ol exposure resulted in a statistically significant increase in the G2M phase (72%) compared to 2ME2 (19%). Apoptosis induction was more pronounced when cells were exposed to ESE-15-ol compared to 2ME2. Spectrophotometric analysis of caspase 8 activity demonstrated that 2ME2 and ESE-15-ol both induced caspase 8 activation by 2- and 1.7-fold respectively indicating the induction of the apoptosis. However, ESE-15-ol exerted all of the above-mentioned effects at a much lower pharmacological concentration (180 nM) compared to 2ME2 (1 µM physiological concentration). CONCLUSION: Computer-based technology is essential in drug discovery and together with in vitro studies for the evaluation of these in silico-designed compounds, drug development can be improved to be cost effective and time consuming. This study evaluated the anticancer potential of ESE-15-ol, an in silico-designed compound in vitro. Research demonstrated that ESE-15-ol exerts antiproliferative activity accompanied with apoptosis induction at a nanomolar concentration compared to the micromolar range required by 2ME2. This study is the first study to demonstrate the influence of ESE-15-ol on morphology, cell cycle progression and apoptosis induction in HeLa cells. In silico-design by means of receptor- and ligand molecular modeling is thus effective in improving compound bioavailability while preserving apoptotic activity in vitro.