[Determination of thresholds values for platelet serotonin and urinary 5-HIAA concentrations for the biological diagnosis of digestive neuroendocrine tumors]. / Quelles valeurs de référence pour la concentration de la sérotonine plaquettaire et du 5-HIAA urinaire pour le diagnostic des tumeurs neuroendocrines digestives ?

OBJECTIVES: Platelet serotonin and its urinary metabolite 5-HIAA (5-hydroxyindolacetic acid) are the main biomarkers measured for the detection of neuroendocrine tumors (NET). We observe in our laboratory many false positives or false negatives for the 2 assays using threshold values given by the manufacturer. We aim to determine our own local threshold values for a better detection of gastrointestinal NETs. METHODS: We studied patients with measurement of platelet serotonin and/or urinary 5-HIAA in University Hospital of Tours between January 2005 and June 2016. We established an « index ¼ cohort with 75% of patients to determine local threshold value for the 2 parameters. A "validation" cohort constituted with 25% of remaining patients allowed us to compare the performances of manufacturer's values with local threshold values. RESULTS: Two hundred ninety patients were included, with 19 suffering from NETs. Local threshold value for platelet serotonin was determined at 5.13 amol/platelet, the one for urinary 5-HIAA at 3.60 µmol/mmol urinary creatinine. Platelet serotonin specificity was better with local threshold value for identical sensibility (0.75). Urinary 5-HIAA sensibility was improved with local threshold value (1 vs 0.667) for identical specificity (0.902). CONCLUSION: Using our local threshold value for platelet serotonin and urinary 5-HIAA improved diagnostic performances of these biochemical markers to detect NETs.

Metabolome analysis for discovering biomarkers of gastroenterological cancer.

Improvements in analytical technologies have made it possible to rapidly determine the concentrations of thousands of metabolites in any biological sample, which has resulted in metabolome analysis being applied to various types of research, such as clinical, cell biology, and plant/food science studies. The metabolome represents all of the end products and by-products of the numerous complex metabolic pathways operating in a biological system. Thus, metabolome analysis allows one to survey the global changes in an organism's metabolic profile and gain a holistic understanding of the changes that occur in organisms during various biological processes, e.g., during disease development. In clinical metabolomic studies, there is a strong possibility that differences in the metabolic profiles of human specimens reflect disease-specific states. Recently, metabolome analysis of biofluids, e.g., blood, urine, or saliva, has been increasingly used for biomarker discovery and disease diagnosis. Mass spectrometry-based techniques have been extensively used for metabolome analysis because they exhibit high selectivity and sensitivity during the identification and quantification of metabolites. Here, we describe metabolome analysis using liquid chromatography-mass spectrometry, gas chromatography-mass spectrometry, and capillary electrophoresis-mass spectrometry. Furthermore, the findings of studies that attempted to discover biomarkers of gastroenterological cancer are also outlined. Finally, we discuss metabolome analysis-based disease diagnosis.

Epidermal growth factor receptor-binding growth factors in the urine of patients with cancers of the digestive tract.

We aimed to assess the diagnostic application of urinary epidermal growth factor receptor (EGFR)-binding growth factors in cancers of the digestive tract. By radioreceptor assay and radioimmunoassay, we determined these growth factors in 115 patients with various cancers of the digestive tract, 30 patients with benign disease, and 40 healthy controls. The receiver operating characteristic (ROC) curve and likelihood ratio were employed to determine the best diagnostic efficiency. Urinary EGFR-binding growth factors in each cancer group were significantly higher than those in the non-cancer groups. Multivariate analysis indicated that the growth factors, determined by both the radioreceptor assay (odds ratio, 1.184; 95% confidence interval,1.077-1.302; P = 0.001) and radioimmunoassay (odds ratio,1.055; 95% confidence interval, 1.002-1.111; P = 0.039), were associated, in a dose-related fashion, with the presence of cancers. By ROC curve analysis, the optimal cutoff values for EGFR-binding growth factors were 25.5 microg/g creatinine (radioreceptor assay) and 33.6 microg/g creatinine (radioimmunoassay). The resulting sensitivity, specificity, diagnostic accuracy, and positive and negative likelihood ratios were 84.4%. 87.5%, 85.2%, 6.75 and 0.18 (for radioreceptor assay) and 86.1%, 67.5%, 81.3%, 2.64 and 0.21 (for radioimmunoassay), respectively. Except for pancreatic cancer the growth factors showed moderate diagnostic efficiency for the other digestive tract cancers. In conclusion, urinary EGFR-binding growth factors were increased in cancers of the digestive tract. They may be used as diagnostic tumor markers.

Biological evaluation of a lipid-mobilizing factor isolated from the urine of cancer patients.

We have previously shown human lipid-mobilizing factor (LMF) to be homologous with the plasma protein Zn-alpha2-glycoprotein in amino acid sequence, electrophoretic mobility, and immunoreactivity. In this study, both LMF and Zn-alpha2-glycoprotein have been shown to stimulate glycerol release from isolated murine epididymal adipocytes with a comparable dose-response profile. Both LMF and Zn-alpha2-glycoprotein caused a stimulation of adenylate cyclase in murine adipocyte plasma membranes in a GTP-dependent process, with maximum stimulation at 0.1 microM GTP and with saturation at protein concentrations of >5 microg/assay. Administration of LMF to exbreeder male mice over a 89-h period produced a decrease in body weight without a change in food and water intake. Body composition analysis showed a 42% reduction in carcass lipid when compared with controls. Treatment of ob/ob mice with human LMF over a 160-h period also produced a decrease in body weight, with a 19% reduction in carcass fat, without a change in body water or nonfat mass. Serum levels of glycerol and 3-hydroxybutyrate were significantly increased, as was oxygen uptake by interscapular brown adipose tissue, providing evidence of increased lipid mobilization and utilization. Human white adipocytes responded to both LMF and isoprenaline to the same extent, although the maximal response was lower than that for murine white adipocytes. These results suggest that LMF not only has the capacity to induce lipid mobilization and catabolism in mice, but it also has the potential to exert similar effects in cachectic cancer patients.

Purification and characterization of a tumor lipid-mobilizing factor.

Cancer patients with weight loss showed urinary excretion of a lipid-mobilizing factor (LMF), determined by the ability to stimulate lipolysis in isolated murine epididymal adipocytes. Such bioactivity was not detectable in the urine of cancer patients without weight loss or in normal subjects. The LMF was purified using a combination of ion exchange, exclusion, and hydrophobic interaction chromatographies to give a single component of apparent Mr 43,000, which showed homology in amino acid sequence with human plasma Zn-alpha2-glycoprotein. Both substances showed the same mobility on denaturing and nondenaturing gels and the same chymotrypsin digestion pattern, both stained heavily for carbohydrate, and they showed similar immunoreactivity. Polyclonal antisera to human plasma Zn-alpha2-glycoprotein was also capable of neutralization of the bioactivity of human LMF in vitro. Using competitive PCR to quantify expression of Zn-alpha2-glycoprotein, we found that only those tumors that were capable of producing a decrease in carcass lipid expressed mRNA for Zn-alpha2-glycoprotein. These results provide strong evidence to suggest that tumor production of Zn-alpha2-glycoprotein is responsible for the lipid catabolism seen in cancer patients.

Urinary gonadotropin peptide in patients with cancer of digestive organs.

Urinary gonadotropin peptide (UGP) has been measured in gynecological and urological cancers, but its usefulness in the diagnosis of cancers of digestive organs has not been investigated. In this report, UGP was measured by sandwich enzyme immunoassay in 311 patients, including 166 patients with cancers of digestive organs and 43 healthy controls. Positive rates of UGP in various cancers of digestive organs were as follows: biliary tract 61.5%, pancreas 61.5%, esophagus 50.0%, liver 38.7%, colon and rectum 24.2%, and stomach 23.9%. The positive rate of UGP in benign diseases was 8.1%, and most false-positive patients were postmenopausal females. Positive rates of UGP were increased at advanced stages of gastric cancers, and UGP was decreased after tumor resection. From these results, it is suggested that UGP can be used as a tumor marker for the cancers of digestive organs.

Urinary epidermal growth factor receptor-binding growth factors in patients with cancers of the digestive tract.

To investigate whether the urinary excretion of epidermal growth factor (EGF) and transforming growth factor-alpha (TGF-alpha) is increased in patients with cancer of the digestive tract, EGF and TGF-alpha were determined in 109 cancer patients and 40 healthy controls. Excluding EGF in hepatocellular carcinoma (HCC) and TGF-alpha in pancreatic cancer, both growth factors in each cancer group were significantly higher than in the control group. A receiver operating characteristic curve and likelihood ratio were applied to obtain the best diagnostic efficiency. Both EGF and TGF-alpha had high specificity (100%) in all cancer group. The high sensitivity of EGF in gastric cancer (100%) and metastatic liver cancer (93.3%), moderate sensitivity of TGF-alpha in metastatic liver cancer (86.6%), colon cancer (80.0%), and HCC (61.7%) suggested that they might be helpful in identifying these cancers. In conclusion, urinary excretion of EGF and TGF-alpha increased in most cancers of the digestive tract. They may be used as tumor markers.

[Value and factors of influence in the combined method of the urine-purple-heat tolerance test in the diagnosis of cancer].

A method combining the urine cancer reaction, purple reaction and heat tolerance test (combined method of urine-purple-heat tolerance) was used to examine 112 normal persons, 110 non-cancer patients and 93 cancer patients. It was found that the accuracy rate of the urine reaction was 82%, of the purple reaction 77.4%, and of the heat tolerance 79%. The combined method showed great diagnostic value for cancers in the digestive tract, such as stomach, biliary duct, colon, pancreas and liver, as well as other cancers, e.g., lung cancer, lymphosarcoma and brain tumor. This method may be best for screening the above tumors. Its positive rate was also high in malignant reticuloma, chronic granulocytic leukemia and reticulosarcoma. The mechanism of the combined method and the influential factors, such as the freshness of the specimen, reactive time, temperature and quality of the reagents are discussed.