epothilone-a and Pheochromocytoma

To characterize neurotoxicity induced by oxaliplatin, bortezomib, and epothilone-B as well as protection against their neurotoxicity using an in vitro model.. Neurotoxicity was evaluated using the neurite outgrowth method in PC12 rat pheochromo-cytoma cells differentiated towards a mature neuronal phenotype, while neuroprotection was explored by simultaneous exposure to 0.5 mM amifostine. The potential markers of neuronal differentiation, cyclin-B2 (Ccnb2) and baculoviral inhibitor of apoptosis repeat-containing 5 (Birc5), were evaluated by quantitative reverse transcription polymerase chain reaction (RT-PCR).. Bortezomib, epothilone-B, and oxaliplatin reduced neurite length to 68%, 78% and 66%, respectively (p<0.05). The percentage of neurite-forming-cells (discriminating neurotoxicity from general cytotoxicity) decreased from 70% (control) to 55% (bortezomib), 46% (epothilone-B), and 51% (oxaliplatin). Amifostine was neuroprotective against oxaliplatin-induced neurotoxicity, increasing both neurite length and neurite-forming-cells. Quantitative-RT-PCR showed a 2.7-fold decrease in Ccnb2 expression in differentiated PC12 vs. undifferentiated cells.. Oxaliplatin, bortezomib, and epothilone-B are neurotoxic in the PC12 model. Amifostine has a neuroprotective effect only against oxaliplatin-induced neurotoxicity, suggesting that these compounds have different mechanisms of neurotoxicity.

Topics: Adrenal Gland Neoplasms; Amifostine; Animals; Antineoplastic Agents; Apoptosis; Boronic Acids; Bortezomib; Cell Differentiation; Cyclin B2; Epothilones; Microtubule-Associated Proteins; Neurites; Neurotoxicity Syndromes; Organoplatinum Compounds; Oxaliplatin; Pheochromocytoma; Pyrazines; Radiation-Protective Agents; Rats; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Survivin; Tumor Cells, Cultured