In two hamster cell lines that differed 100-fold in their vinblastine sensitivity, dissolution of the mitotic spindle by vinblastine in living cells correlated with cytotoxicity from vinblastine expressed as suppression of colony formation. The effect on the spindle apparatus occurred in 30 sec or less and thus provides a rapid assay for determining the cytotoxic effects of the Vinca alkaloids,...

Naturally occurring vinca alkaloids, vincristine and vinblastine, at micromolar concentrations enhanced the ornithine decarboxylase activity in a dose-response manner in primary cultures of Ehrlich ascites carcinoma cells. After 8 h of culture in the presence or absence of vinblastine, cycloheximide was added to the medium, a 4.5-fold increase in the half-life of the ornithine decarboxylase act...

background: stress may cause damages to dna or/and change the ability of the cells to overcome these damages. it may also cause irregularities in the cell cycle and induce abnormal cell divisions through glucocorticoid-dependent functions. the abnormal cell divisions, in turn, lead to chromosomal mal-segregation and aneuploidy. in this study, the effects of the stress hormone, hydrocortisone (h...

On-patent and off-patent drugs with previously unrecognized anticancer activity could be rapidly repurposed for this new indication given their prior toxicity testing. To identify such compounds, we conducted chemical screens and identified the antihelmintic flubendazole. Flubendazole induced cell death in leukemia and myeloma cell lines and primary patient samples at nanomolar concentrations. ...

The purpose of this study is to examine the gastrointestinal disorders after injection of vinblastine (2 mg kg-1 b.w. i.v.) in rats. Animals were divided into two equal groups: Group 1 was considered as a control group (NaCl, 0.9%). Group 2 was treated with intravenous injection of vinblastine for 7 days. Loperamide (2 mg kg-1) was injected in a saline solution subcutaneously to induce constipa...

The cytotoxic, antimitotic, and growth inhibition properties of a pho toactive analogue of vinblastine, Ar-(p-azidobenzoyl)-A''-0-aminoethylvindesine (NÕBV), and vinblastine on P388 murine leukemia cells were compared. After 72-h exposure, the 50% drug-inhibitory concentrations for exponentially growing P388 leukemic cells were 1.2 n\i for NABV and 0.6 n\i for vinblastine. The ultrastructural ...

Chronic lymphocytic leukemia (CLL) characteristically maintains high levels of the anti-apoptotic protein Bcl-2, thus protecting them from apoptotic death and leading to an accumulation of mature resting B cells. Many other hematopoietic malignancies including acute promyelocytic leukemia (APL) also depend upon Bcl-2 family proteins for survival, suggesting that Bcl-2 proteins are excellent tar...

P-Glycoprotein-mediated drug efflux can yield a multidrug-resistance (MDR) phenotype that is associated with a poor response to cancer chemotherapy. Pervilleine A, a novel tropane alkaloid obtained from a chloroform extract of Erythroxylum pervillei as the result of bioactivity-guided fractionation, was found to restore the vinblastine sensitivity of cultured multidrug-resistant KB-V1 and CEM/V...

Objective(s): Chemoresistance remains the main causes of treatment failure and mortality in cancer patients. There is an urgent need to investigate novel approaches to improve current therapeutic modalities and increase cancer patients' survival. Induction of drug efflux due to overexpression of                  P-glycoproteins is considered as an important leading cause of multidrug resistance...