Bcl-2 protects neuronal cells against taxol-induced apoptosis by inducing multi-nucleation.
Taxol-induced peripheral neuropathy is a commonly-occurring side-effect in the treatment of cancer patients with taxoteres or taxanes. Taxol is known to induce apoptosis in a number of tumor cells. This report documents that, similar to proliferating cells, taxol induces apoptosis in NGF-differentiated PC12 cells, as assessed by exogenous FITC-annexin-V binding and nuclear fragmentation. It is shown that PC12 cells that stably overexpress Bcl-2 are protected against the toxic effect of taxol, as evidenced by the XTT assay and by a decreased fraction of propididum iodide positive cells in a dye exclusion test. Also the number of annexin-V-positive cells and the number of fragmented nuclei are lower in the Bcl-2 transfected cells. The effect is similar to the protective effect of Bcl-2 against NGF deprivation in differentiated PC12 cells. Although taxol forced both wild-type and Bcl-2-overexpressing cells into a mitotic state, only in Bcl-2-overexpressing cells did this lead to the appearance of metabolically active, multi-nucleated cells. This suggests that Bcl-2 is able to induce an alternative escape pathway, downstream of the G2/M block, in taxol-treated differentiated PC12 cells.
Department of Neurobiology, Janssen Research Foundation, Beerse, Belgium.
R
R
Nuydens
G
G
Dispersyn
G
G
Van Den Kieboom
M
M
de Jong
R
R
Connors
F
F
Ramaekers
M
M
Borgers
H
H
Geerts
D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D015153:Blotting, Western; D002453:Cell Cycle / Q000502:physiology; D002454:Cell Differentiation; D002455:Cell Division; D002467:Cell Nucleus / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D005434:Flow Cytometry; D006801:Humans; D008856:Microscopy, Fluorescence; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D016716:PC12 Cells; D017239:Paclitaxel / Q000494:pharmacology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D014162:Transfection
D000972:Antineoplastic Agents, Phytogenic; D019253:Proto-Oncogene Proteins c-bcl-2; D017239:Paclitaxel