• 대한방사선방어학회:학술대회논문집
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• 2009.04a
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• pp.94-95
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• 2009

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• Proceedings of the Korean Biophysical Society Conference
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• 1999.06a
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• pp.70-70
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• 1999

Experimental studies have implicated the wild type p53 in cellular response to radiation. Whether altered p53 function can lead to changes in clinical radiocurability remains an area of ongoing study. This study was performed to investigate whether any correlation between change of p53 and outcome of curative radiation therapy in patients with head and neck cancers.(omitted)

• Korean Journal of Environmental Biology
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• v.22 no.3
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• pp.472-477
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• 2004

To study the radiation related gene expression in mutants of Bacillus lentimorbus WJ5 induced by gamm radiation, the simultaneous gene expression was analyzed by DNA micro array. We constructed DNA chips including two thousand randomly digested genome spots of B. lentimorbus WJ5 and compared its quantitative aspect with seven mutants induced by gamma radiation $(^{60}/Co)$. From the cluster analysis of gene expression pattern, totally 408 genes were expressed and 27 genes were significantly upregulated by the gamma radiation in all mutants. Especially, genes involved in repair (mutL, mutM), energy metabolism (acsA, sdhB, pgk, yhjB, citB), protease (npr), and reduction response to oxidative stress (HMM) were simultaneously upregulated. It seems that the induction of the direct and/or indirect repair related genes in mutants induced by gamma radiation could be remarkably different from the adaptive responses against acute exposure to radiation.

• Radiation Oncology Journal
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• v.35 no.4
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• pp.317-324
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• 2017

Purpose: This study evaluated outcomes of radiotherapy (RT) after chemotherapy in limited-stage head-and-neck diffuse large B-cell lymphoma (DLBCL). Materials and Methods: Eighty patients who were treated for limited-stage head-and-neck DLBCL with CHOP (n = 43) or R-CHOP (n = 37), were analyzed. After chemotherapy, RT was administered to the extended field (n = 60) or the involved field (n = 16), or the involved site (n = 4). The median dose of RT ranged from 36 Gy in case of those with a complete response, to 45-60 Gy in those with a partial response. Results: In all patients, the 5-year overall survival (OS) and disease-free survival (DFS) rates were 83.9% and 80.1%, respectively. In comparison with the CHOP regimen, the R-CHOP regimen showed a better 5-year DFS (86.5% vs. 73.9%, p = 0.027) and a lower rate of treatment failures (25.6% vs. 8.1%, p = 0.040). The volume (p = 0.047) and dose of RT (p < 0.001) were significantly reduced in patients treated with R-CHOP compared to that in those treated with CHOP. Conclusion: The outcomes of RT after chemotherapy with R-CHOP were better than those of CHOP regimen for limited-stage head-and-neck DLBCL. In patients treated with R-CHOP, a reduced RT dose and volume might be feasible without increasing treatment failures.

• Environmental Mutagens and Carcinogens
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• v.15 no.2
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• pp.94-99
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• 1995

The adaptive response and cross-adaptive response to sister chromatid exchanges (SCEs) and DNA single-strand breaks (SSBs) in Chinese hamster ovary (CHO)-K$_1$ cells treated with ultraviolet radiation (UV), ethyl methanesuffonate (EMS), or bleomycin (BLM) were investigated. Two assays were used in this study; SCEs and alkaline elution. The pretreatment with low conditioning dose of 2 mM EMS or 1 J/m$^2$ UV decreased the yield of SCEs induced by subsequent treatment with 8 mM EMS, 5 J/m$^2$ UV or 5 $\mu$g/ml BLM. And the pretreatment with low conditioning dose of 1 $\mu$g/ml BLM decreased the yield of SCEs induced by subsequent treatment with 5 $\mu$g/ml BLM or 5 J/m$^2$ UV. The rejoining of DNA SSBs in cells subsequently treated with 2 J/m$^2$ UV, 50 mM EMS or 400 $\mu$g/ml BLM is higher than that only treated with 2 J/m$^2$ UV, 50 mM EMS or 400 $\mu$g/ml BLM. These results suggest that there are the adaptive response and cross-adaptive response to SCEs, and is the adaptive response to the rejoining of DNA SSBs in CHO cells.

• Archives of Pharmacal Research
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• v.21 no.6
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• pp.640-644
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• 1998

AT cells exhibit defective cell cycle regulation following DNA damage. Previous studies have shown that induction of p53 and p2i proteins are delayed in response to ionizing rad iation, resulting in the failure of G1/S checkpoint in AT cells. In this study, further investigation of the molecular mechanisms underlying G1/S phase progression in AT cells was conducted. Exponentially growing normal and AT cells were exposed to 2 Gly of ionizing radiation and the expression levels and functional activities of Rb and E2F-1 proteins were determined. We observed overexpression of hyperphosphorylated Rb and E2F-1 proteins in AT cells, which was unaffected post-irradiation. Furthermore, gel shift assays showed that E2F-1-DNA binding was constitutive in AT cells, whereas it was inhibited in control cells following exposure to ionizing radiation. The data suggests that abnormalities in the function of Rb and E2F-1 proteins may also be responsible for the failure of AT cells to arrest in the G1/S checkpoint in response to DNA damage.

• Korean Journal of Veterinary Pathology
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• v.2 no.1
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• pp.37-46
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• 1998

It has been known that $\gamma$-irradiation usually induces cell death in regenerating stem cell in normal tissues like skin, intestine and hematopoietic organ. The experiment were carried out to evaluate the early response of radiation injury in radiosensitive and intermediate radiosensitive tissues in feeding and starving rats with the doses of 3.5 and 7.0 Gy. The results of the study showed that the histological phenomenon was apoptosis in the doses of the radiation as the early response of tissue injury. Apoptosis were showed organ-specific and cellular specific responses suggesting that the selection of apoptosis be exactly focused on highly renewal organs and cells. It was interesting that the rats starved for 72 hours prior to irradiation induced less apoptosis in liver than fed rats. As for cellular responses it appeared that apoptotic cells were mostly distributed in ductal or periportal cells in liver of feeding rats unlikely in liver of Starving rots which showed no difference in zonal distribution. In salivary gland apoptotic cells in fed rats were highly induced in intercalating and ductal cell population than in acinar cell population although unlikely in starved rats. This study showed the value of apoptosis using the detection system of TUNEL for evaluating cellular damage after radiation injury and the diminished effect of starvation on cell damage after ionizing irradiation.

• Radiation Oncology Journal
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• v.13 no.2
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• pp.191-198
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• 1995

Purpose: This analysis was to compare the result of radiation alone and chemoradiation in cervical cancer in terms of response, survival, failure, and complication. Materials and Methods: A retrospective analysis of 135 cervical cancer patients treated with definitive radiotherapy from November 1985 to December 1991 was performed. Fifty-six patients were treated with radiation alone and 79 patients were treated with cisplatin-based chemotherapy plus radiation. Follow-up period ranged from 5 to 105 months with a median 47 months. According to the FIGO classification, the patients were subdivided into 18 $(13.3\%)$ stage IB, 7 $(5.2\%)$ stage IIA, 97 $(71.9\%)$ stage IIB, and 9 $(6.7\%)$ stage IIIB. Results: A complete response was noted in 51 patients $(91.1\%)$ of the radiation alone group, and 68 patients $(86.1\%)$ of the chemoradiation group. There was no statistical difference in complete response rate between the two groups. Overall survival rate at 5 years was $73.3\%$. According to stage, overall survival rates at 5 years were $88.9\%$ in stage IB, $85.7\%$ in stage IIA, $73.8\%$ in stage IIB, and $37.5\%$ in stage IIIB, respectively. According to treatment modality, overall survival rates at 5 years were $81.9\%$ in the radiation alone group, $67.0\%$ in the chemoradiation group (p=0.22). Disease-free survival rate at 5 years were $70.4\%$ in the radiation alone group. $68.5\%$ in the chemoradiation group (p=0.85) Locoregional control rates at 5 years were $76.1\%$ in the radiation alone group, $73.8\%$ In the chemoradiation group (p=0.70). Distant disease-free survival rates at 5 years were $83.9\%$ in the radiation alone group, $90.3\%$ in the chemoradiation group (p=0.59). Treatment-related bone marrow suppressions were noted in 3 $(5.4\%)$ patients of the radiation alone group, 14 patients $(17.7\%)$ of the chemoradiation group (p(0.05). Grade 2 vesical complications were noted in 14 patients of the radiation alone group. and 10 Patients of the chemoradiation group. Grade 2 rectal complications were noted in 2 patients of the radiation alone group, and 3 Patients of the chemoradiation group. One case of rectal perforation was noted in the chemoradiation group, and grade 2 small bowel obstructions were noted in 2 patients of the radiation alone group. There were no statistical differences in the incidence of vesicar, rectal, and small bowel complicaions between the two groups. Conclusion: No statistical difference was found between the radiation alone group and the chemoradiation group in terms of response, survival, and failure. but the incidence of bone marrow suppression was higher in the chemoradiation group.

• Molecular & Cellular Toxicology
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• v.5 no.2
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• pp.165-171
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• 2009

Biomarkers indicating past exposure to radiation have not yet been entirely satisfactory. In this study, we validated several genes reported as radiation response genes, as biomarkers to detect past exposure to radiation in occupationally exposed workers, especially workers in the medical field. A total of 54 radiation workers in hospital were investigated for radiation exposure dose. Their average radiation dose of recent one year was 1.09 mSv ($\pm$1.63) with a 10.63 mSv ($\pm$12.91) cumulative dose. The results of the multiple regression analysis for the various variables indicate that the Hsc70 (P=0.0292) and ORAL (P=0.0045) may be candidate biomarkers for the recent 1 year radiation exposure in radiation workers, whereas AEN (P=0.0334) and PGAMI (P=0.0003) might be for cumulative exposure.

• Radiation Oncology Journal
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• v.10 no.2
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• pp.261-266
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• 1992

We analyzed retrospectively the patients of granulocytic sarcoma treated with radiotherapy at the Department of Radiation Oncology, Yonsei University College of Medicine from Mar 1987 to Mar.1992 in an attempt to review our experience with irradiation of granulocytic sarcoma and to evaluate the treatment results for the radiation dose response. Fourteen lesions of granulocytic sarcoma in 9 patients were developed in variable clinical settings such as AML, CML and without leukemia. The involved lesions were bone, lymph node, soft tissue and skin in descending order of occurrence. All of the lesions in 9 patients were treated with external beam radiotherapy (Co-60 or electron beam). Both age distribution and clinical settings did not show any correlation with the response to treatment. The response to treatment seemed to be better for lesions in the bone than in other involved lesions. The majority received local irradiation of a total dose of more than 2000 cGy. Radiation dose of more than 2000 cGy showed excellent local control of $100\%$, (11/11), while local control decreased to $33\%$(1/3) with total dose less than 2000 cGy. In conclusion, local radiotherapy seems to be very effective for palliative or curative aim of granulocytic sarcoma, and a radiation dose more than 2000 cGy is highly recommended.