title: Alteration of opioid peptide circadian rhythm in cancer patients.
abstract: Endogenous opioid peptides have been seen to play a role in regulating immunity and tumor growth. This study was carried out to investigate opioid activity in human cancer. We evaluated by radioimmunoassay beta-endorphin plasma levels on blood samples collected at 9.00 a.m. from 121 cancer patients and 42 healthy subjects. In 22 cancer patients and in 12 controls, beta-endorphin circadian rhythm was also investigated. Finally, in 14 cancer patients and in 10 controls GH, PRL, FSH, LH and cortisol serum levels were measured after the administration of a metenkephalin analogue, FK 33-824 (0.3 mg i.v.). No significant differences were seen in beta-endorphin mean levels between cancer patients and normal subjects. Moreover, no differences were found between patients with or without metastases, nor between those with or without chronic pain. beta-Endorphin circadian rhythm appeared to be altered in 16/22 cancer patients, and anomalous hormonal responses to FK 33-824 were seen in 13/14 patients. This study shows an altered opioid activity in human neoplasms, whose clinical significance remains to be determined.
authors.affiliation: Division of Radiation Oncology, Ospedale San Gerardo, Monza, Milano, Italia.
authors.forename: S
authors.initials: S
authors.lastname: Barni
authors.forename: P
authors.initials: P
authors.lastname: Lissoni
authors.forename: F
authors.initials: F
authors.lastname: Rovelli
authors.forename: S
authors.initials: S
authors.lastname: Crispino
authors.forename: F
authors.initials: F
authors.lastname: Paolorossi
authors.forename: D
authors.initials: D
authors.lastname: Esposti
authors.forename: G
authors.initials: G
authors.lastname: Esposti
authors.forename: F
authors.initials: F
authors.lastname: Fraschini
authors.forename: G
authors.initials: G
authors.lastname: Tancini
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000378:metabolism*; D002940:Circadian Rhythm; D005405:D-Ala(2),MePhe(4),Met(0)-ol-enkephalin; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000378:metabolism*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008175:Lung Neoplasms / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010908:Pituitary Hormones, Anterior / Q000097:blood; D011863:Radioimmunoassay; D001615:beta-Endorphin / Q000097:blood / Q000502:physiology*
chemical_list: D010908:Pituitary Hormones, Anterior; D001615:beta-Endorphin; D005405:D-Ala(2),MePhe(4),Met(0)-ol-enkephalin; D006854:Hydrocortisone