Basic study for genetic therapy by analysis of intracellular signal transduction in thyroid carcinoma cell

1)既往流行病学研究表明，甲状腺组织易发生辐射致肿瘤。为了探讨甲状腺细胞对辐照是否存在组织特异性的细胞内反应，我们进行了多项研究。为此，我们使用了具有正常遗传背景的原代培养甲状腺细胞，以及一些从甲状腺癌中建立的具有遗传缺陷的细胞系，例如p53突变。2 Gy辐照后甲状腺原代细胞和甲状腺癌细胞的存活率分别为18%和58%。辐照后G1阻滞仅在原代甲状腺细胞中出现，而在甲状腺癌细胞中未出现。这表明g1的停止依赖于p53的状态。我们发现辐照后甲状腺细胞很少发生凋亡。接下来，我们检测放疗后p53下游基因（p21/WAF1、Bax和FAS/APO1）的表达变化。p21/WAF1基因表达增加，Bax和FAS/APO基因表达未见变化。这些结果提示辐照后甲状腺组织有特异性反应。我们将这些数据发表在Cancer杂志上。2)我们开发了半自动化尿碘测量仪。我们在《临床化学》上发表了这些数据。

1) Previous epidemiology study shows thyroid tissue is prone to radiation induced tumorigenesis. To investigate whether the tissue specific intracellular responses to irradiation in thyroid cells is existed or not, we have done the several studies. To this purpose, we used primary cultured thyroid cell that has normal genetic background, and some cell lines established from thyroid carcinoma that have genetic defects, for instance, p53 mutation. The survival rates after 2 Gy irradiation were 18% and >58% in primary thyroid cell and thyroid carcinoma cell line, respectively. G1 arrest after irradiation has been shown only in primary thyroid cell but not in thyroid carcinoma cells. It suggests G1arrest is depend on p53 status. We can find apoptosis is rare event in thyroid cells after radiation exposure. Next, we checked the change of the expression of the p53 down stream genes (p21/WAF1, Bax and FAS/APO1) after radiation. Although the expression of p21/WAF1 gene was increased, no change of expression was observed in Bax and FAS/APO gene. These results suggest there is thyroid tissue specific response after irradiation. We published these data on Cancer Res.2) We developed semi-automated measurement apparatus of urinary iodine. We published these data on Clinical Chemistry.