直肠癌及直肠正常组织的IR和~1H及^(31)P NMR谱研究

Study on Malignant and Normal Rectum Tissues Using IR and ~1H and ^(31)P NMR Spectroscopy

对12例直肠组织的红外光谱图进行了测定,并对6例直肠癌变及正常组织的固体1H和31PNMR谱与另外6例直肠癌变及正常组织的液体1H和31P-NMR谱进行研究。结果表明,(1)直肠癌变和正常组织的红外光谱中存在明显差异。(2)在固体1H和31P NMR谱中,1H NMR谱上癌组织的脂肪酸与水相关的特征峰面积的比值I(5+6+7)/I(1+2+3+4)明显变低,依据I(5+6+7)/I(1+2+3+4)比值可区分癌变与正常组织。31P NMR谱上,癌变组织的最强峰的化学位移明显向高场偏移。(3)在液体1H和31P NMR谱中,1H NMR谱上癌组织中3.20处峰强较正常组织高,表明与癌变密切相关的胆碱类化合物包括游离的胆碱、磷酸胆碱及甘油磷酸胆碱等的量增大。31P NMR谱上,癌变组织的强度最大峰的化学位移分别为1.18,1.26,1.29,1.37,正常组织的化学位移为1.70和2.18,癌变组织的强度最大峰的化学位移明显向高场偏移。通过癌变与正常组织代谢物1H NMR谱峰强度和31P NMR谱峰化学位移的差异,可以区分直肠癌变和正常组织,核磁共振1H和31P NMR谱技术可能发展成为一种诊断直肠癌的新方法。

In the present paper, NMR spectroscopy, an effective tool to detect the variation in molecular structure and changes in chemical composition of metabolites in tissues, was used to study the differences between malignant and normal tissues from rectum. ^1 H and ^3l p spectra of seven malignant rectum tissue samples and five normal control tissues were investigated by using a 300 M NMR spectrometers and compared with the results of the infrared spectra of normal and malignant rectum organ tissues. The results indicate that the ^1H and ^31 p spectra of rectum cancer tissues are significantly different from those of the normal controls and most differences present in the form of variation in relative intensities of the characteristic peaks of various metabolites. Systematic differences in the NMR spectra between malignant tissues and normal controls are as follows： in the ^1H NMR spectra, differences lie in fatty acids with the concentration of fatty acid decreasing significantly in malignant tissues. In the ^31p NMR spectra, differences lie in phospholipid, with the chemical shift of phospholipid decreasing significantly in malignant tissues. This phenomenon may reflect the fact that the activity of protein synthesis is enhanced in cancerous tissues. The difference in the chemical shift of phospholipid between normal rectal tissue and malignant tissue may be considered as a detection criterion. Therefore, the above spectral variations in ^31p NMR spectra may be utilized as a potential tool to diagnose rectum cancer.