Related Experiment Videos
High levels of expression and nuclear localization of interleukin-1 beta converting enzyme (ICE) and CPP32 in
A Nakagawara1, Y Nakamura, H Ikeda
1Division of Biochemistry, Chiba Cancer Center Research Institute, Japan. akiranak@biolab.kazusa.or.jp
Abstract:
Neuroblastomas frequently show spontaneous regression and differentiation, which may at least partly be regulated by signaling through nerve growth factor and its receptors, TRK-A and p75LNTR. We studied 52 neuroblastic tumors to test whether the cell death-related proteases, interleukin-1 beta converting enzyme (ICE), CPP32, and Ich-1, were involved in the regression of the tumors. High levels of expression of ICE and CPP32 were significantly correlated with a high level of TRK-A expression, single copy of N-myc, younger age, lower stages, and better prognosis. The immunohistochemical studies and Western analyses as well as the terminal dUTP-biotin nick end labeling (TUNEL) method revealed that both ICE and CPP32 were translocated from the cytoplasm into the nuclei in regressing, apoptotic tumor cells. Our results suggest that ICE and CPP32 cysteine proteases may play an important role in regulating the apoptotic process of the favorable neuroblastomas.
Insights
Interleukin-1 beta converting enzyme (ICE) and CPP32 proteases are linked to neuroblastoma regression. High expression of these proteases correlates with favorable outcomes in neuroblastoma tumors.
Area of Science:
- Oncology
- Molecular Biology
- Cell Death Research
Background:
- Neuroblastomas often undergo spontaneous regression and differentiation.
- Nerve growth factor signaling via TRK-A and p75LNTR receptors may regulate this process.
- The role of specific proteases in neuroblastoma apoptosis is not fully understood.
Purpose of the Study:
- To investigate the involvement of cell death-related proteases, specifically interleukin-1 beta converting enzyme (ICE) and CPP32, in neuroblastoma regression.
- To correlate the expression of these proteases with known prognostic markers in neuroblastic tumors.
Main Methods:
- Studied 52 neuroblastic tumors.
- Utilized immunohistochemical studies, Western analyses, and terminal dUTP-biotin nick end labeling (TUNEL) assay.
- Assessed expression levels of ICE, CPP32, and TRK-A, and N-myc copy number.
Main Results:
- High expression of ICE and CPP32 significantly correlated with high TRK-A expression, single N-myc copy, younger age, lower tumor stage, and better prognosis.
- Immunohistochemistry and Western blot analyses showed translocation of ICE and CPP32 from cytoplasm to nuclei in apoptotic, regressing tumor cells.
- TUNEL assay confirmed apoptosis in these cells.
Conclusions:
- ICE and CPP32 cysteine proteases are strongly implicated in the apoptotic process of neuroblastoma.
- These proteases likely play a crucial role in the spontaneous regression observed in favorable neuroblastomas.
- Findings suggest potential therapeutic targets for improving neuroblastoma treatment outcomes.