Alteration of opioid peptide circadian rhythm in cancer patients.
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.
Barni
S
S
Division of Radiation Oncology, Ospedale San Gerardo, Monza, Milano, Italia.
Lissoni
P
P
Rovelli
F
F
Crispino
S
S
Paolorossi
F
F
Esposti
D
D
Esposti
G
G
Fraschini
F
F
Tancini
G
G
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*
D010908:Pituitary Hormones, Anterior; D001615:beta-Endorphin; D005405:D-Ala(2),MePhe(4),Met(0)-ol-enkephalin; D006854:Hydrocortisone