[Ectopic production of HCG beta by bladder carcinoma in vitro and in vivo].
BACKGROUND
Ectopic production of immunoreactive hCG/hCG beta (IR-hCG beta) by bladder tansitional cell carcinoma cell lines was investigated in vitro and in vivo.


METHODS
As an in vitro study, IR-hCG beta in culture media from 2 bladder transitional cell carcinoma cell lines (KoTCC-1 and HT-1197) was analyzed by three kinds of enzyme immunoassays (EIA) which were specific for intact hCG, free hCG beta and beta-core fragment (beta-CF). As an in vivo study, distribution of IR-hCG beta was analyzed in tumor tissues, sera, and urine of the nude mice and the nude rat transplanted with KoTCC-1 cell line.


RESULTS
Both of the cell lines were determined to secrete IR-hCG beta into the media, which consisted principally of free hCG beta. Intact hCG and beta-CF were scarecely detected in the media. Immunohistochemical study revealed the localization of IR-hCG beta in transitional cell carcinoma cells of the transplanted tumor. Although a large amount of IR-hCG beta could be detected in both of the serum and urine from the animals, there were quantitative and qualitative differences between serum and urinary IR-hCG beta. Quantitatively, the concentrations of IR-hCG beta in the urine were consistently much higher than those in the serum. Qualitatively, free hCG beta was exclusively detected in the serum whereas a large amount of beta-CF, in addition to free hCG beta, were found in the urine. Intact hCG could not be detected in both serum and urine. These distributions of IR-hCG beta in the animals bearing tumors were completely analogous to those in patients with bladder carcinoma.


CONCLUSIONS
The present results suggested that ectopic production of IR-hCG beta by bladder carcinoma is not rare phenomenon and it is clinically useful as a tumor marker when beta-CF is measured in the urine.
Morisue
K
K
Department of Urology, Shinko Hospital, Japan.
Yamanaka
N
N
Eto
H
H
Kamidono
S
S
Nishimura
R
R
D000818:Animals; D014408:Biomarkers, Tumor / Q000652:urine; D002295:Carcinoma, Transitional Cell / Q000378:metabolism*; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000096:biosynthesis* / Q000652:urine; D006729:Hormones, Ectopic / Q000096:biosynthesis* / Q000652:urine; D006801:Humans; D008297:Male; D051379:Mice; D008819:Mice, Nude; D051381:Rats; D014407:Tumor Cells, Cultured; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis / Q000378:metabolism*
D014408:Biomarkers, Tumor; D018997:Chorionic Gonadotropin, beta Subunit, Human; D006729:Hormones, Ectopic