Related Experiment Videos
[Immunohistochemical study of radiation-induced apoptosis and oncogenes]
M Hasegawa1, M Yamakawa, N Mitsuhashi
1Department of Radiology and Radiation Oncology, Gunma University, School of Medicine.
Abstract:
Relationships between radiation-induced apoptosis and oncogenes or suppressor genes (p53, MDM2, c-myc, p21ras and bcl-2) were immunohistochemically studied in 7 human tumors transplanted to nude mice. The most radiosensitive ependymoblastoma was negative for p53 and c-myc, however, the other 6 tumors were positive for them. Following irradiation, the ependymoblastoma became p53 positive, and showed the highest incidence of apoptosis among the 7 tumors. In addition, bcl-2 expression in this tumor was slightly different from that in the others.
Insights
Radiation therapy can alter tumor suppressor genes like p53, influencing cancer cell death (apoptosis). Ependymoblastoma showed increased apoptosis after irradiation, linked to p53 expression changes.
Area of Science:
- Oncology
- Molecular Biology
- Cancer Research
Context:
- Investigating the role of oncogenes and tumor suppressor genes in radiation-induced apoptosis.
- Utilizing a xenograft model of human tumors in nude mice.
Purpose:
- To explore the relationship between specific genes (p53, MDM2, c-myc, p21ras, bcl-2) and apoptosis following radiation exposure.
- To compare gene expression and apoptosis incidence across different human tumor types.
Summary:
- Immunohistochemical analysis of 7 human tumors revealed varying p53 and c-myc expression. The radiosensitive ependymoblastoma, initially negative for p53 and c-myc, became p53 positive post-irradiation, exhibiting the highest apoptosis rate.
- This suggests a correlation between p53 expression changes and radiosensitivity. Bcl-2 expression also showed subtle differences in the ependymoblastoma compared to other tumors.
Impact:
- Provides insights into the molecular mechanisms underlying tumor response to radiation.
- Highlights the potential of p53 as a biomarker for radiosensitivity.
- Informs the development of targeted cancer therapies.