Evaluation of intestinal cancer by 1H HR-MAS NMR spectroscopy: A new diagnostic tool?

Background:  Previous studies have demonstrated that cancer cells harbor unique metabolic characteristics relative to healthy counterparts. The current study is a prospective ex-vivo HR-MAS NMR analysis of malignant colorectal cancer (CRC) tissue specimens and its corresponding benign tissues. Objective:  To assess the HR-MAS Spectroscope qualitatively & to analyze significant difference between the normal, benign and malignant intestinal mucosa. Materials and Methods:  Between November 2013and January 2016, 36 consecutive patients with confirmed CRC were recruited to a prospective observational study. Fresh tissue samples were obtained from center of tumor and 5 cm from tumor margin from surgical resection specimens. Samples were run in duplicate where tissue volume permitted to compensate for anticipated sample heterogeneity. Typically, the sample was packed into a 4 mm ZrO2 rotor of 50 ?l capacity; a volume of 20?l of D2O having 0.03% TSP was used as a chemical shift reference. The sample-rotor-setup was then transferred into the HR-MAS NMR probe for analysis. Results:  A total of 36 spectra were acquired (center of tumor, n = 18; 5 cm from tumor margin, n = 18). The malignant clustering occurs due to increased Val (0.90ppm), Lac (1.34ppm), Ala(1.48ppm) levels of acetate (1.90ppm), glutamate (2.35ppm), taurine (3.23 ppm), choline containing compounds (3.20-3.22ppm), glycine (3.56ppm), lactate (4.12ppm) and ?-H of Leu, Ileu, Val, Lys, Ala (3.76-3.79ppm . In addition unique metabolic profiles were observed for tumors of differing T-stage. The information gathered from clustering in PCA had highly suggested that malignancy induces metabolic perturbations at cellular levels. Conclusions:  HR-MAS NMR profiling demonstrates cancer-specific metabolic signatures in CRC and reveals metabolic differences between benign and malignant tumors. In addition, this approach reveals that tumor metabolism undergoes modification during local tumor advancement, offering potentia