中文摘要：

2目的：探索几种细胞株对UVB紫外线的耐受性。方法：0、20和50 mJ/cm紫外线照射后，利用MTT、荧光素酶报告基因检测和克隆形成率实验，检测人表皮细胞HaCaT、人黑色素细胞A875、人肺腺癌细胞A549和H322、人肝癌细胞HepG2的存活及2增殖能力。结果：MTT实验结果表明HaCaT、A875、A549、H322和HepG2细胞在受到20和50 mJ/cm紫外线照射后第1天，细胞活力均显著降低（P＆lt;0.05），到照射后第3天，细胞活力仍显著低于未照射组（＆lt;0.05）。克隆形成率实验结果表明，HaCaT、A875和2HepG2细胞在照射后，细胞增殖能力受到显著抑制。荧光素酶活性检测实验结果表明，A549细胞在受到20和50 mJ/cm紫外线照射后第5和第10天，细胞活力显著低于未照射组（P〈0.05）。结论：UVB紫外线对表皮细胞、肺腺癌细胞和肝癌细胞的存活和增殖能力均产生影响，其中正常表皮细胞HaCaT细胞对UVB紫外线的耐受性大于肿瘤来源的A875、A549、H322和HepG2细胞。

英文摘要：

OBJECTIVE： To investigate the tolerance of various kinds of cell lines to ultraviolet B radiation. METHODS：Cell viability and proliferation were detected by MTT,firefly luciferase activity and cloning efficiency assays after cells including epidermal cells （HaCaT）,melanocytes （A875）,pulmonary adenocarcinoma cells （A549 and 2H322） and hepatocarcinoma cells （HepG2） of human were irradiated with ultraviolet B at dose of 20 or 50 mJ/cm. RESULTS：Cell viability including epidermal cells （HaCaT）,melanocytes （A875）,pulmonary adenocarcinoma cells （A549 and H322） and human hepatocarcinoma cells （HepG2）,decreased significantly 1 day after ultraviolet B irradiation 2at doses of 20 and 50 mJ/cm （P〈0.05）. The viability of these cells were still lower than untreated control cells 3 days after irradiation. Finally,the proliferative ability of all the examined cells was suppressed after ultraviolet B irradiation at doses 2of 20 and 50 mJ/cm（P〈0.05）,as shown by cloning efficiency assays. Further firefly luciferase activity assay indicated that the viability of A549 cells were suppressed 5 and 10 days after exposure（P〈0.05）.CONCLUSION：Ultraviolet B irradiation affected the viability and proliferation of epidermal cell,lung adenocarcinma cell and hepatoma cell. Normal epidermal cell HaCaT possessed the more tolerance than A875,A549,H322 and HepG2 cells which is the source of tumors on ultraviolet B.