PubMed · 4194081
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
A Subirana. 1970. Round table on epilepsy.. https://pubmed.ncbi.nlm.nih.gov/4194081/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Cellular insensitivity to vinca alkaloids is suggested to be primarily due to drug efflux by P-glycoprotein (P-gp). The anti-epileptic phenytoin (DPH), which does not bind to P-gp, can selectively enhance vincristine (VCR) cytotoxicity in wild-type (WT) or multidrug-resistant (MDR) cells. We now demonstrate that the protein phosphatase inhibitor okadaic acid (OKA) can mimic the effect of DPH by selectively enhancing cytotoxicity of vinblastine (VBL), but not taxol and doxorubicin, in human leukaemia HL-60 cells. Both DPH and OKA potentiate the anti-mitotic effects of VBL by enhanced damage to the mitotic spindle, resulting in prolonged growth arrest. Also, unlike VBL alone, in human leukaemia or non-small-cell lung carcinoma cells treated with VBL plus DPH, recovery from damage to the mitotic spindle is compromised in drug-free medium and cell death by apoptosis in interphase ensues. Since protein phosphatases are involved with the regulation of metaphase to anaphase transit of cells during the mitotic cycle, enhanced VBL cytotoxicity in the presence of DPH or OKA may involve effects during metaphase on the mitotic spindle tubulin leading to growth arrest and apoptosis in interphase. These novel results suggest that DPH or OKA could be powerful tools to study cellular effects of vinca alkaloids and possibly for the development of novel therapeutic strategies.
Phenytoin, one of the most widely prescribed anticonvulsants, and steroids are routinely utilized for seizure prophylaxis in patients with various intracranial tumors. We report a case of severe Stevens-Johnson syndrome (SJS), documented by biopsy, which occurred in a patient, with metastatic squamous cell carcinoma receiving phenytoin, whole-brain radiation therapy (WBRT), and a tapering steroid dose. The pathogenesis and implications are then briefly discussed.