胃肠道肿瘤细胞生物标志物的7.0T磁共振波谱分析

Ex vivo H^1-MRS for evaluation of human gastrointestinal carcinoma with 7.0 T NMR spectrometer

目的采用7.0 T高频MRI设备尝试发现胃肠道肿瘤细胞(胃癌)代谢物的脂肪酸相关代谢物在磁共振波谱(MRS)上所呈现的生物学标识特征,分子水平综合分析胃肠道肿瘤脂肪酸波谱特异性表现,为临床在体胃癌MRS诊断提供依据。方法培养收集正常胃黏膜上皮细胞系GES-1和胃癌细胞系低分化胃癌细胞BGC-823,采用7.0 T MRI检测完整细胞的氢质子波谱,并定量计算谱线中主要脂肪酸代谢物的浓度,采用两独立样本t检验对浓度进行比较。结果 GES-1细胞株与BGC-823细胞株具有不同的波谱特征,GES-1细胞的脂肪酸相关代谢物浓度明显高于BGC-823细胞,其中脂质甲基为2.796±0.975∶0.943±0.629(P<0.001),脂质亚甲基为14.660±5.106∶4.473±2.296(P<0.001),N-乙酰神经氨酸为2.638±1.080∶0.528±0.734(P<0.001)。结论离体细胞株MRS研究可以提供肿瘤细胞分子水平更多相关信息,能反映细胞的生理状态,综合分析两类细胞株波谱特征能更全面地获取胃癌演变过程中代谢物变化信息,为MRS在胃肠道肿瘤的相关研究及临床应用提供一定的理论依据。

Objective The aim of the present study was to examine the metabolic profile of normal and tumoral gastric cell with ex vivo high resolution magnetic resonance spectrometer（7.0 T NMR） to get information on the molecular steps involved in gastric carcinogenesis and the identification of biochemical markers useful for the development of in vivo MRS methodologies to diagnose gastric carcinoma in clinical situation. Methods The Normal gastric mucosa epithelial cell（GES-1） and gastric cancer cell（BGC-823） line were collected and analyzed with NMR, then the concentrations of fatty acids were calculated. Results The spectrums of the GES-1 and BGC-823 showed that presences of differently distributed fatty acids were the markers of a physiological condition. The GES-1 cells had a higher concentration lipid contents than GES-1did in two independent-samples t tests（Lipid methyl：2.796±0.975 vs. 0.943±0.629, P〈0.001; Lipid methylene 14.660±5.106 vs. 4.473±2.296, P〈0.001; N-acetylneuraminic acid 2.638±1.080 vs. 0.528±0.734, P〈0.001）. Conclusion Ex vivo1H-MRS is a viable and powerful probing means for molecular information in human normal and tumoral cell lines. This research may constitute the basis for a biochemical classification of cancer cell using in vivo MRS for clinical purposes.