Protein synthesis measurement in cancer patients with 13C valine

• Published in: Clinica chimica acta Vol. 252; no. 1; pp. 51 - 60
• Main Authors: Egerland, A., Reynier, J.P., Ballevre, O., Dicostanzo, J., Obled, C., Arnal, M.
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier B.V 15.08.1996; Elsevier
• Subjects: Aged; Biological and medical sciences; Blood Proteins - biosynthesis; Cancer; Carbon Isotopes; Colon - chemistry; Colon - metabolism; Colonic Neoplasms - chemistry; Colonic Neoplasms - metabolism; Female; Gastroenterology. Liver. Pancreas. Abdomen; Humans; Life Sciences; Male; Medical sciences; Middle Aged; Parenteral nutrition; Parenteral Nutrition, Total; Protein synthesis; Radioactive Tracers; Rectal Neoplasms - chemistry; Rectal Neoplasms - metabolism; Stable isotope; Stomach. Duodenum. Small intestine. Colon. Rectum. Anus; Tumors; Valine - administration & dosage; Parenteral nutrition; Stable isotope; Protein synthesis; Cancer; Human; Carcinoma; Isotope labelling; Nutrition; Malignant tumor; Parenteral administration; Valine; Rectum; Digestive diseases; Intestinal disease; Tumor; Colon; CANCER
• ISSN: 0009-8981; 1873-3492
• DOI: 10.1016/0009-8981(96)06313-9

The flooding dose technique is a method that uses tracer amino acids to measure the rate of protein synthesis in tissues in vivo. This technique involves the injection of a large amount of unlabelled amino acid together with the tracer to minimize difference in isotopic enrichment of the free amino acid in plasma and tissue compartments which represent the precursor pool of protein synthesis. Seven patients with localized colorectal carcinoma received a total parenteral nutrition before surgery and protein synthesis was measured in tumour and colon after administration of a large dose of valine (20% atom percent excess). The enrichment of free valine in plasma and tissues was measured by GCMS and the enrichment of protein-bound valine into tumour and colon by IRMS. The fractional synthesis rate in tumours was 13.44 ± 6.9%/day compared to a value of 10.9 ± 8.1%/day in healthy colon. The lack of significant different probably relates to the low number of patients and the variability of protein synthesis rate in tumours.