peptide-yy and Adenoma

Patients with craniopharyngioma (CP) have disturbances of the hypothalamic-pituitary axis and serious comorbidities such as obesity. We hypothesized that the secretion of hormones regulating the nutritional status is altered in adult patients with CP compared with patients with non-functioning pituitary adenoma (NFPA).. WE INCLUDED 40 CP (50% MALES, MEAN AGE: 49.6±14.3 years) and 40 NFPA (72.5% males, mean age: 63.4±9.8 years) patients. We measured glucose, insulin, leptin, total ghrelin, peptide-YY (PYY) and cholecystokinin (CCK) during oral glucose tolerance test (OGTT). Fat mass (FM) was determined by dual X-ray absorptiometry.. Gender distribution was not significantly different, but CP patients were significantly younger (P<0.001). CP patients had significantly higher BMI and FM than NFPA patients (BMI 32±8 vs 28±4 kg/m(2), P=0.009 and FM 37±9 vs 33±9%, P=0.02). Fasting glucose level (84±12 vs 78±11 mg/dl, P=0.03), leptin (27.9±34.2 vs 11.9±11.6 μg/l, P=0.008) and leptin levels corrected for percentage FM (0.66±0.67 vs 0.32±0.25 μg/l%, P=0.005) were significantly higher in CP than in NFPA patients, whereas ghrelin was significantly lower (131±129 vs 191±119 ng/l, P=0.035). Insulin, PYY and CCK did not differ significantly between groups. After glucose load, leptin decreased significantly in CP patients (P=0.019). In both groups, ghrelin decreased significantly during OGTT (both P<0.001). The percentage decline was significantly smaller for CP. PYY and CCK increased equally after glucose in both groups.. Our patients with CP have more metabolic complications than our patients with NFPA. The levels of leptin and ghrelin at fasting status and after glucose seem to be altered in CP, whereas changes in insulin, PYY and CCK do not seem to be responsible for the metabolic changes in these patients.

Topics: Absorptiometry, Photon; Adenoma; Adult; Aged; Appetite Regulation; Blood Glucose; Body Fat Distribution; Case-Control Studies; Cholecystokinin; Craniopharyngioma; Female; Ghrelin; Glucose Tolerance Test; Humans; Insulin; Leptin; Male; Middle Aged; Obesity; Peptide YY; Pituitary Neoplasms

Peptide hormone receptors overexpressed in human malignant neoplasms are potential targets for diagnostic scintigraphy and radiotherapy. One such receptor is the neuropeptide Y (NPY) receptor, mediating primarily feeding behavior in the brain but shown recently to play a role in breast cancer. In this study, the presence of NPY receptors was evaluated in another group of gynecological tumors, namely ovarian tumors, using in vitro receptor autoradiography with (125)I-labeled peptide YY and receptor subtype selective analogs. Remarkably, all 10 investigated inhibin-expressing granulosa cell tumors, Leydig cell tumors, and Sertoli-Leydig cell tumors expressed NPY receptors. In contrast, receptors were found in only seven of 22 ovarian adenocarcinomas (32%). Pharmacological characterization of the expressed NPY receptor subtypes in the various tumors revealed the presence of Y1, Y2, or both. In addition, Y1 receptors were observed in intra- and peritumoral blood vessels as well. NPY receptors were not expressed in three ovarian adenomas, three borderline tumors, four fibromas and fibrothecomas, and one dysgerminoma. This is the first time that NPY receptors are described in human ovarian tissue. They may play a role in the pathogenesis and also in the pathophysiology of ovarian malignancies. Moreover, the high incidence and density of NPY receptors in sex cord-stromal tumors suggest that these receptors represent a new potential target for the diagnostic and therapeutic administration of NPY analogs in these tumors.

Topics: Adenocarcinoma; Adenoma; Autoradiography; Biomarkers, Tumor; Cell Line, Tumor; Female; Fluorescent Antibody Technique, Indirect; Humans; Iodine Radioisotopes; Neoplasms, Gonadal Tissue; Ovarian Neoplasms; Ovary; Peptide YY; Receptors, Neuropeptide Y

The aim of endoscopic polypectomy is to prevent colorectal cancer, as it is assumed that most, if not all, large bowel cancers are derived from adenomatous polyps. While it is now recognized that colonic endocrine cells, like other mucosal epithelial cells, have an endodermal origin, they are relatively sparse components of large bowel tumors. Peptide YY (PYY) is the most abundant endocrine regulatory peptide localized to the distal bowel. Endocrine cells, like the other cells of the mucosal epithelia, are derived from a common stem cell in the base of the crypts. The presence of endocrine peptides may thus be viewed as a marker for cellular differentiation in the gut. PYY was therefore measured in colonic carcinomas and adenomatous polyps, as its absence would be evidence in favor of genetic alterations in epithelial stem cell maturation. PYY concentrations in extracts of surgically removed colonic carcinomas (n = 22) from all regions were very low compared with those of adjacent normal bowel. Similarly, PYY concentrations in extracts of polyps (n = 39) obtained during endoscopic polypectomy were also very low when compared with those of adjacent normal mucosa. These varied between 1 and 11% of the normal epithelial content, depending upon the region. Low PYY levels appeared to reflect the malignant potential of these lesions: highest in tubular polyps, lower in villous polyps, and lowest in carcinomas. The very low concentrations of PYY in adenomatous polyps, like those of colonic cancer, are consistent with epithelial dysplasia and the incomplete formation of mucosal endocrine cells. These findings support the hypothesis of an adenoma to carcinoma sequence in colonic cancer.

Topics: Adenoma; Carcinoma; Colonic Neoplasms; Colonic Polyps; Humans; Intestinal Mucosa; Osmolar Concentration; Peptide YY; Peptides; Radioimmunoassay