Short incubation with 2-methoxyestradiol kills malignant glioma cells independent of death receptor 5 upregulation.

We investigated the effects of 2-methoxyestradiol (2-ME), a promising new antitumor agent, on viable cell number and nuclear morphology of malignant glioma cells (three human and one rat glioma cell lines) and analyzed the controversial role of death recepor 5 (DR5) upregulation in 2-ME induced apoptosis. Microtiter-tetrazolium (MTT) assays showed a significant reduction of viable cells after incubation with 2 microM and 20 microM 2-ME for 48 and 72 hours in all cultures. In the 20 microM concentration, there were even significant effects in the majority of shorter incubation periods. Hoechst 33258 stains showed a substantial amount of cells with nuclear fragmentation indicating a late stage of apoptosis after 20 microM 2-ME treatments of 24 hours and more. The role of the DR5-mediated extrinsic apoptotic pathway was further studied in the three human glioma cell lines; 50 ng/ml of the DR5 ligand TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) and 2 microM 2-ME showed no synergism, as determined by MTT assays. Real-time PCR revealed no significantly increased amount of DR5 mRNA, suggesting that receptor upregulation does not play a major role for 2-ME-induced apoptosis in glioma cells, in contrast to data for a breast cancer cell line in the literature.

Micromolar concentrations of 2-methoxyestradiol kill glioma cells by an apoptotic mechanism, without destroying their microtubule cytoskeleton.

The purpose of this study was to investigate the potential effects of 2-methoxyestradiol, a natural mammalian steroid, in glioma cells, since antiproliferative effects of this compound had been shown earlier in several leukemia and carcinoma cell lines. The effects of 0.2, 2 and 20 microM concentrations of 2-methoxyestradiol were measured in three malignant human glioma cell lines (U87MG, U138MG, LN405) and one malignant rat glioma cell line (RG-2) using a microtiter-tetrazolium (MTT) assay. In all cell lines, a significant reduction of the viable cell number by more then 75% occurred ( P < 0.05) for concentrations of 2 and 20 microM 2-methoxyestradiol after 6 days. A concentration of 0.2 microM had smaller effects (10-40% cell reduction), which were significant in two of the cell lines tested. The apoptotic nature of cell death was further analyzed in U87MG and RG-2 cells. Caspase-3 activity was significantly induced to levels between 3.4- and 23-fold after 4 days for the two higher 2-methoxyestradiol concentrations (P < 0.05). In the cell line RG-2 nuclear fragmentation was visible in many nuclei, following stains with Hoechst H33258. A round cell morphology occurred in most treated cells, which was not accompanied by a complete destruction of the microtubule network, as it can be observed with other microtubule targeting drugs.

Pathophysiology of impaired right and left ventricular function in chronic embolic pulmonary hypertension: changes after pulmonary thromboendarterectomy.

STUDY OBJECTIVES: This study sought to evaluate the pathophysiology of left and right heart failure in patients with chronic thromboembolic pulmonary hypertension (CTEPH) who were hospitalized to undergo pulmonary thromboendarterectomy (PTE). DESIGN: Thirty-nine patients (16 women and 23 men; mean +/- SD age, 55+/-12 years) with severe CTEPH were examined before and 13+/-8 days after PTE by way of transthoracic echocardiography and right heart catheterization. MEASUREMENTS AND RESULTS: Examination results confirmed in all cases that before surgery the right ventricles were enlarged and systolic function was impaired. Moderate to severe tricuspid valve regurgitation was observed. Left ventricular eccentricity indexes reflected a leftward displacement of the interventricular septum. End-diastolic left ventricular size and systolic function had decreased, and the left ventricular filling pattern showed impaired diastolic function. After surgery, mean pulmonary artery pressure was significantly lower (48+/- 10 mm Hg vs. 25+/-7 mm Hg; p<0.05). The calculated end-diastolic and end-systolic right ventricular areas had decreased: 30+/-7 cm(2) vs 21 +/-5 cm(2) (p<0.05) and 24+/-6 cm(2) vs. 14+/-4 cm(2) (p<0.05), respectively. Right ventricular fractional area change had increased (20+/-7% vs. 33+/-8%; p<0.05). Most of the patients exhibited a marked decrease in the severity of tricuspid regurgitation. Septal motion, left ventricular systolic function, and diastolic filling pattern returned to normal values (early to late diastolic left ventricular inflow ratio, 0.70+/-0.33 vs. 1.35+/-0.51; p<0.05). The mean cardiac index also improved (2.7+/-0.6 L/min/m(2) vs. 3.7+/-0.8 L/min/m(2)). CONCLUSIONS: In CTEPH, functions are impaired in the right as well as the left ventricles of the heart. Improved lung perfusion and the reduction of right ventricular pressure overload are direct results of PTE, which in turn bring a profound reduction of right ventricular size and a recovery of systolic function. Normalization of interventricular septal motion as well as improved venous return to the left atrium lead to a normalization of left ventricular diastolic and systolic function, and the cardiac index improves.