In vitro characterization of lung cancers by the use of ¹H nuclear magnetic resonance spectroscopy of tissue extracts and discriminant factor analysis

Abstract

Using proton magnetic resonance spectroscopy (1H MRS) spectra were obtained in vitro from extracts of four types of lung cancer (squamous cell, adenocarcinoma, large cell, small cell) and normal lung. The hydrophilic phase of the chloroform/methanol-water extracts yielded several distinct peaks. Among them the peak areas for cholines, creatines, glycine, and alanine, and their ratios were calculated and used as parameters to characterize different lung tissues. The ratios, cholines/alanine and glycine/alanine, were significantly (P < 0.001 to P < 0.05) higher for the normal lung than lung cancers. Creatines/glycine and creatines/cholines generally provided good discrimination (P < 0.001 to P < 0.05) between any two types of lung cancer. When data were further analyzed by discriminant factor analysis, there was 81.5 to 90.7% accuracy in predicting between normal lung and each cancer type, or among the four types of lung cancer. These results suggested that 1H MRS might be useful as an adjunct modality in the differential diagnosis of lung cancers.

Metabolomic studies of human lung carcinoma cell lines using in vitro1H NMR of whole cells and cellular extracts

“…Thus 17 samples were prepared and a total of 33 spectra were included in the PCA of the correlation matrix. The size of the final dataset is comparable to the reported pattern-recognition studies of NMR metabolomics data (32,33,49). Error analysis suggests that only the first eigenvalue is clearly distinct, corresponding to one significant PC.…”

Lactate, choline, and creatine levels measured by vitro 1H‐MRS as prognostic parameters in patients with non‐small‐cell lung cancer

“…Few studies have focused on 1 H-MRS of lung cancer. However, in a study comparing different types of lung cancer and normal lung, Hanaoka et al (13) found significantly different values in the ratios of Cr/ glycine and Cr/Cho among almost all types. Cr/glycine, Cr/Cho, and Cr/alanin ratios are higher in squamous cell carcinoma than in normal lung.…”

“…Consequently, only in vitro MRS studies have been conducted on lung tissue. Hanaoka et al (13) reported that Lac in lung tissue increased rapidly after surgical disruption. However, since it has not been possible to standardize experimental conditions to accurately quantify Lac, it is difficult to measure the amount of Lac in lung cancer tissue.…”

“…We determined he identity of each MRS peak by comparing the peak with the spectrum of synthetic counterpart substances and also by referring to the literature (13). We performed quantification by comparing the integrated TSP signal with the Lac, Cr, and Cho signals in the specimen spectrum after baseline correction.…”

Effects of ligation and reperfusion of hepatic afferent vessels on the composition of liver cell membranes in the rat:1H- and31P-magnetic resonance spectroscopic analysis

“…The extraction was performed according to Folch et al 9 This method was designed originally for the extraction of hydrophobic substances, but later also found to be useful for extracting the low molecular weight hydrophilic organic compounds essentially without any in vitro modifications, such as oxidation and hydrolysis. [10][11][12] Liver tissue (4.0-5.0 g wet wt) was homogenized with 20-fold volume of chloroform-methanol (2:1), and then the homogenate was filtered. A five-fold volume of H 2 O was added to the filtrates and allowed to stand for about 24 h at 4ЊC.…”