Project description:Here, male and female B6C3F1 mice were given single or fractionated whole-body exposure(s) to a monoenergetic carbon ion radiotherapy beam at the Heavy Ion Medical Accelerator in Chiba, Japan, matching the radiation quality delivered to the normal tissue ahead of the tumour volume. These mice were then monitored for the remainder of their lifespan and a large number of T cell lymphomas were analysed, alongside those arising in mice exposed to equivalent doses of standard Cs137 gamma ray-irradiation. Using genome-wide DNA copy number analysis to identify genomic loci involved in radiation-induced lymphomagenesis and subsequent detailed analysis of Notch1, Ikaros, Pten, Trp53 and Bcl11b genes we compared the genetic profile of the carbon ion- and gamma ray-induced tumours. The canonical set of genes previously associated with radiation-induced T cell lymphoma was identified in both radiation groups. While the pattern of disruption of the various pathways was somewhat different between the radiation types, most notably Pten mutation frequency and loss of heterozygosity flanking Bcl11b, the most striking finding was the observation of large interstitial deletions at various sites across the genome in carbon ion-induced tumours, which were only seen infrequently in the gamma ray-induced tumours analysed. 32 unique tumours (12 gamma ray-induced, 20 carbon ion-induced) each with sex-matched reference DNA
Project description:Here, male and female B6C3F1 mice were given single or fractionated whole-body exposure(s) to a monoenergetic carbon ion radiotherapy beam at the Heavy Ion Medical Accelerator in Chiba, Japan, matching the radiation quality delivered to the normal tissue ahead of the tumour volume. These mice were then monitored for the remainder of their lifespan and a large number of T cell lymphomas were analysed, alongside those arising in mice exposed to equivalent doses of standard Cs137 gamma ray-irradiation. Using genome-wide DNA copy number analysis to identify genomic loci involved in radiation-induced lymphomagenesis and subsequent detailed analysis of Notch1, Ikaros, Pten, Trp53 and Bcl11b genes we compared the genetic profile of the carbon ion- and gamma ray-induced tumours. The canonical set of genes previously associated with radiation-induced T cell lymphoma was identified in both radiation groups. While the pattern of disruption of the various pathways was somewhat different between the radiation types, most notably Pten mutation frequency and loss of heterozygosity flanking Bcl11b, the most striking finding was the observation of large interstitial deletions at various sites across the genome in carbon ion-induced tumours, which were only seen infrequently in the gamma ray-induced tumours analysed.
Project description:To examine whether the local carbon ion radiotherapy affects the characteristics of the metastatic tumors, the expression profiles of the primary tumors and the lung metastases were studied in a mouse squamous cell carcinoma model by applying local radiotherapy with no irradiation (negative control), gamma-ray irradiation (reference beam), and carbon-ion irradiation. Keywords: mouse, squamous cell carcinoma, primary tumor, lung metastases, radiotherapy, carbon ion, gamma ray
Project description:To examine whether the local carbon ion radiotherapy affects the characteristics of the metastatic tumors, the expression profiles of the primary tumors and the lung metastases were studied in a mouse squamous cell carcinoma model by applying local radiotherapy with no irradiation (negative control), gamma-ray irradiation (reference beam), and carbon-ion irradiation. Keywords: mouse, squamous cell carcinoma, primary tumor, lung metastases, radiotherapy, carbon ion, gamma ray A highly metastatic mouse squamous cell carcinoma NR-S1 was implanted into the hind leg of synergetic C3H/HeNrs mice and irradiated with 5 Gy of carbon ion beam. 8 Gy of gamma ray was used as a reference beam. At 2 weeks after the irradiation, the lung tissue was sampled. In order to collect samples of primary tumors, the tumors were implanted in other mice and irradiated in the same manner, and the primary tumors were collected at 1 week after the irradiation. The tumor cells of the primary and metastatic tumors were collected by laser microdissection, and oligonucleotide microarray analysis of the irradiated primary tumors and the metastatic tumors were all performed in comparison to the non-irradiated primary tumor by two-color methods.
Project description:Gene expression profiling was used to identify genes that display radiation-induced transcriptional change over tumor histopathology. Keywords: mouse squamous cell carcinoma, fibrosarcoma and mammary carcinoma, gamma-irradiation, carbon ion irradiation, resected sample, transplanted tissues
Project description:Purpose: The high relative biologic effectiveness (RBE) of high-linear energy transfer (LET) heavy-ion radiation has enabled powerful radiotherapy. The potential risk of later onset of secondary cancers, however, has not been adequately studied. We undertook the present study to clarify the RBE of therapeutic carbon ion radiation and molecular changes that occur in the rat mammary cancer model. Methods and materials: We observed 7-8-week-old rats (ACI, F344, Wistar, and Sprague-Dawley) until 1 year of age after irradiation (0.05-2 Gy) with either 290 MeV/u carbon ions with a spread out Bragg peak (LET 40-90 keV/mum) generated from the Heavy-Ion Medical Accelerator in Chiba or (137)Cs gamma-rays. Results: Carbon ions significantly induced mammary carcinomas in Sprague-Dawley rats but less so in other strains. The dose-effect relationship for carcinoma incidence in the Sprague-Dawley rats was concave downward, providing an RBE of 2 at a typical therapeutic dose per fraction. In contrast, approximately 10 should be considered for radiation protection at low doses. Immunohistochemically, 14 of 18 carcinomas were positive for estrogen receptor alpha. All carcinomas examined were free of common H-ras and Tp53 mutations. Importantly, lung metastasis (7%) was characteristic of carbon ion-irradiated rats. Conclusions: We found clear genetic variability in the susceptibility to carbon ion-induced mammary carcinomas. The high RBE for carbon ion radiation further supports the importance of precise dose localization in radiotherapy. Common point mutations in H-ras and Tp53 were not involved in carbon ion induction of rat mammary carcinomas.
Project description:Zebrafish is an ideal model for the toxicity studies on medicines and environmental genetic toxicants.Different development defects were observed in zebrafish embryos exposed to -ray and heavy ion (carbon or iron) irradiation We used microarrays to detail the gene expression situation after radiation.
Project description:Gene expression profiling was used to identify genes that display radiation-induced transcriptional change over tumor histopathology. Keywords: mouse squamous cell carcinoma, fibrosarcoma and mammary carcinoma, gamma-irradiation, carbon ion irradiation, resected sample, transplanted tissues C3H/HeMs male mice were irradiated by gamma-rays (30Gy, 50Gy, 70Gy) or carbon ions (30Gy) as local irradiation in single doses to hind legs where each tumor was transplanted. Animals were sacrificed either before irradiation (pre) or 1 day after irradiation (day 1) for expression analysis.