Bag1 and Yama/CPP32 expressions of SCC and its significance in radiosensitivity

1. 应用免疫组织化学方法对T1-2口腔鳞状细胞癌患者BAG1的表达进行研究。22例患者中有13例（59%）出现BAG1过表达。这种过表达常见于肿瘤侵袭的结缔组织。Western-blotting分析与视觉结果相关。BAG1过表达在有淋巴结转移的患者中高于无淋巴结转移的患者（89%比38%，P<0.03）2。细胞系辐照实验用saos-2 （p53 null）亲本细胞系建立了BAG1和bcl - xl强表达的新细胞系。通过集落形成实验和流式细胞术分析这些基因表达对辐射敏感性的影响。辐照实验采用Co60。Western blotting证实BAG-1过表达。结果：1)菌落形成试验。5Gy和10Gy单剂量照射后，Bcl-xL、Bag1和亲本细胞系的存活率依次较小。2)流式细胞术分析。流式细胞术显示，Bag1过表达细胞系的凋亡分数（如低于2c的分数）小于亲本细胞系。仅在Bag1过表达细胞系中观察到g1阻滞。

1. BAG1 expression in T1-2 oral squamous cell carcinoma22Patients with oral SCC were studied on BAGI1expression by using immunohistochemical method. BAG1 over-expression was observed in 13/22 (59%) patients. The over-expression was frequently seen in the connective tissue with tumor invasion. Western-blotting analysis correlated to the visual findings. BAG1 over-expression was more frequently seen in cases with lymph-node metastasis than those without it (89% vs. 38% , P<0.03)2. Irradiation experiment in cell linesNew cell lines with strong BAG1 and B cl-xL expression were established from saos-2 (p53 null) parent cell line. Colony formation assay and flow cytometric analysis were carried out to see the effect of those gene expressions on radiation sensitivity. Co60 was used for the irradiation experiment. BAG-1 over-expression was confirmed by Western blotting. Results: 1) colony formation assay. Surviving fractions after 5Gy and 10Gy single dose irradiation was smaller in the following order: Bcl-xL, Bag1, and parent cell lines. 2) Flow cytometric analysis. Apoptotic fraction, e.g. under-2C fraction on flow cytometry, was smaller in the Bag1 over-expression cell line than the parent cell line. G1-block was observed only in the Bag1 over-expression cell line.