Related Experiment Videos
The CD95 (APO-1/Fas) system mediates drug-induced apoptosis in neuroblastoma cells
S Fulda1, H Sieverts, C Friesen
1Division of Hematology/Oncology, University Children's Hospital, German Cancer Research Center, Heidelberg.
Abstract:
Anticancer agents have been shown to trigger apoptosis in chemosensitive tumors such as neuroblastomas. We previously identified activation of the CD95 system as one of the key mechanisms for doxorubicin-induced apoptosis in leukemic T cells. Here, we report that therapeutic concentrations of doxorubicin, cisplatinum, and VP-16 led to induction of CD95 receptor and CD95 ligand (CD95-L) that mediated cell death in chemosensitive neuroblastoma cells. Using F(ab')2 anti-CD95 antibody fragments to interfere with CD95-L-receptor interaction markedly reduced apoptosis induced by those drugs in vitro. Cyclosporin A inhibited induction of CD95 mRNA and CD95-L mRNA and blocked drug-mediated apoptosis. Drug-induced apoptosis involved activation of caspases (interleukin 1beta-converting enzyme/Ced-3-like proteases) and processing of the prototype caspase substrate PARP and was completely blocked by benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone, a peptide inhibitor of caspases. In addition, neuroblastoma cells that were resistant to CD95-triggered apoptosis also displayed cross-resistance to chemotherapeutic agents. These data provide new clues for understanding the molecular requirements for drug-induced apoptosis in chemosensitive neuroblastoma cells by demonstrating that cell death was mediated via the CD95-L-receptor system and may open new avenues for targeting drug resistance of neuroblastoma.
Insights
Chemotherapy drugs like doxorubicin induce apoptosis in neuroblastoma cells via the CD95 system. Blocking this pathway reduces cell death, offering new strategies against drug-resistant neuroblastoma.
Area of Science:
- Oncology
- Molecular Biology
- Immunology
Background:
- Anticancer agents induce apoptosis in chemosensitive tumors, including neuroblastomas.
- The CD95 system's role in doxorubicin-induced apoptosis was previously established in leukemic T cells.
Purpose of the Study:
- To investigate the role of the CD95 system in mediating apoptosis induced by chemotherapeutic agents in neuroblastoma cells.
- To explore the potential of targeting the CD95 pathway to overcome drug resistance in neuroblastoma.
Main Methods:
- Treatment of neuroblastoma cells with doxorubicin, cisplatinum, and VP-16.
- Inhibition of CD95-ligand interaction using F(ab')2 anti-CD95 antibody fragments.
- Assessment of apoptosis, mRNA induction, caspase activation, and PARP processing.
- Evaluation of drug resistance in cells resistant to CD95-triggered apoptosis.
Main Results:
- Therapeutic concentrations of doxorubicin, cisplatinum, and VP-16 induced CD95 receptor and CD95 ligand (CD95-L) expression, mediating cell death.
- Interference with CD95-L/receptor interaction significantly reduced drug-induced apoptosis.
- Cyclosporin A inhibited CD95 and CD95-L mRNA induction and blocked apoptosis.
- Drug-induced apoptosis involved caspase activation and PARP processing, blocked by a caspase inhibitor.
- Neuroblastoma cells resistant to CD95-triggered apoptosis showed cross-resistance to chemotherapeutic agents.
Conclusions:
- Drug-induced apoptosis in chemosensitive neuroblastoma cells is mediated through the CD95-L/receptor system.
- The CD95 pathway is a critical component of chemotherapy-induced cell death in neuroblastoma.
- Understanding this mechanism may provide new therapeutic strategies for overcoming drug resistance in neuroblastoma.