本文提出结合生物组织DNA 提取技术和拉曼光谱技术来系统研究胃癌不同发生过程中的组织DNA 空间结构的方法。实验中,首先提取涉及胃癌发病过程中的胃粘膜正常上皮组织、肠化组织和腺癌组织的基因组DNA,分别对其进行拉曼光谱检测,根据拉曼谱图特征,详细分析了基因组DNA 的结构变化。实验结果表明,胃粘膜正常组织DNA 中有稳定的磷酸骨架;肠化组织基因组DNA 拉曼特征峰在1 090 cm-1 处谱峰强度低于1 050 cm-1处谱峰强度,表明其磷酸骨架变得不稳定,其它位置的谱峰与正常组织相似;腺癌组织基因组DNA 拉曼特征峰在1 090 cm-1 附近出现双峰,其相对于1 050 cm-1 处谱峰强度更强,提示DNA 有可能出现断链并再次形成了稳定的磷酸骨架,在950 cm-1、1 010 cm-1、1 100~1 600 cm-1 波段的特征谱峰与正常组织DNA 相比变化也较大,说明脱氧核糖和碱基可能由于DNA 断链也随之改变。这些结果提示胃癌的发生过程中DNA 结构变化过程可能是：胃粘膜正常组织具有稳定的DNA 磷酸骨架,在致病因素作用下发展为具有不稳定磷酸骨架DNA 的肠化组织,最后组织DNA 磷酸骨架断裂并重新形成稳定的DNA 磷酸骨架,致胃癌发生。

A method for systematically investigating the DNA space structure of different issue during the occurring process of adenocarcinoma is proposed, by incorporating issue DNA extraction technology and Raman spectroscopy technology. In experiment, DNA solutions of normal gastric mucosa, intestinal metaplasia and adenocarcinoma are firstly extracted, and then their Raman spectra are measured, respectively. According to the Raman spectra, genomic DNA is analyzed in detail. The experimental results show that: DNA of normal gastric mucosa has stable phosphate backbone; Since the peak intensity at 1 090 cm-1 is lower than that at 1 050 cm-1, phosphate backbone in DNA of intestinal metaplasia becomes unstable, while the rest spectra peaks are similar to those in normal gastric mucosa; In terms of adenocarcinoma DNA, double peaks at 1 090 cm-1 whose intensity are higher than 1 050 cm-1, are observed, which indicates that DNA chain is broken and re-forms a double stabilized phosphate backbones. In addition, peaks at 950 cm-1, 1 010 cm-1, 1 100~1 600 cm-1 also exhibit obvious difference compared with normal gastric mucosa, which shows that deoxyribose and bases are changed due to broken of DNA. All these results indicate that the DNA variation process during the occurring process of adenocarcinoma may be: the stable DNA phosphate backbone in normal gastric mucosa change into unstable DNA phosphate backbone in intestinal metaplasia issue under affecting of pathogenic factors, and finally, DNA phosphate backbone is broken and re-forms a double stabilized phosphate backbones, which causes the occurring of adenocarcinoma.