Increase in Frequency of HPRT Mutation in Tongue Cancer Patients After Radiotherapy: Two Cases

舌癌病患放射治療後HPRT基因突變頻率變化之兩例病例報告

陳虹汶(Hong-Wen Chen) ； 賴國筑(Kuo-Chu Lai) ； 林芳仁(Fang-Jen Lin) ； 賴允亮(Yuen-Liang Lai) ； 黃正仲(Jeng-Jong Hwang)

《醫護科技學刊》 5卷3期 (2003/07) Pp. 185-193

https://doi.org/10.6563/TJHS.2003.5(3).1

摘要

本研究報告兩位舌癌病患其周邊血液T淋巴球細胞中，次黃嘌吟－鳥糞吟磷酸核醣基轉化酶基因突變頻率，在放射治療前、治療期間以及放射治療後的變化。為了監測放射治療對基因的傷害反應，本研究採用免疫螢光染色法量測次黃嘌吟－鳥糞嘌吟磷酸核醣基轉化酶之基因的突變頻率。這兩位病患均接受傳統根治性放射治療。即腫瘤部份接受總劑量達70Gy。每位病患均接受二次周邊血液採集：放射治療前、放射治療達36-40Gy時以及放射治療剛結束時。研究結果顯示次黃嘌吟－鳥糞嘌吟磷酸核醣基轉化酶基因的突變頻率，在放射治療期間並未有顯變化；但在放射治療後，則較放射治療前有三倍的顯著增加，顯示病患在接受放射治療時，確實有引發基因突變的風險。

關鍵字

放射治療 ； 次黃嘌呤－鳥糞嘌吟磷酸核醣基轉化酶基因突變頻率 ； 舌癌

並列摘要

The mutation frequency of the hypoxanthine-guanine phosphoribosyl transferase gene (HPRT ) in the peripheral T-lymphocytes of two patients treated with radiotherapy (RT) for tongue cancers was studied. The mutation or variant frequency (Vf) at the HPRT locus was assayed by an immunofluorescent staining method to monitor the genotoxic effects of RT. Both patients underwent conventional radical RT to a total tumor dose of 70 Gy, without chemotherapy (CT). The peripheral blood samples were obtained three times from each patientbefore RT (pre-RT), at a cumulative dose of 36-40 Gy (during RT), and immediately after the last irradiation (post-RT).
The HPRT variant frequency did not change significantly during RT as compared to that of pre-RT, but increased significantly at post-RT. The Vf of HPRT in these tongue cancer patients post-RT exhibited a three-fold increase over that of pre-RT, implying a risk of genetic mutation for patients treated with RT.

並列關鍵字

radiotherapy ； HPRT mutant frequency ； tongue cancer

參考文獻

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