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The measurement of the peptide hormones in saliva. 2. Chorionic gonadotropin subunits in pregnancy.

The alpha and beta subunits of the human chorionic gonadotropin (HCG) were measured during pregnancy in the saliva of a first group (no. = 23) and in the serum and saliva of a second group (no. = 25). Only ten pregnant women had normal gestation, the remaining 39 being diagnosed as miscellaneous pathologies, the threatened (or impending) abortion being the most frequent (no. = 19). The mean serum levels of alpha-HCG increase from 75.97 +/- 18.59 ng/ml (X +/- SEM) during the first trimester to 341.98 +/- 65.09 ng/ml during the third trimester of the gestation. The mean salivary concentration of the alpha HCG seems unmodified during pregnancy (approximately 10 ng/ml), but large interindividual variations were observed (limits 0.10-28.78 ng/ml) possibly due to the non-homogeneity of the investigated groups. The presence of the beta-HCG subunit in saliva could not be assessed, the great part of the values being aggregated around the sensitivity limit of the RIA technique (0.2 ng/ml). The physiological significance of the presence of the HCG and of its subunits in saliva as well as the ways to elucidate the possible selective role of the blood-saliva barrier are discussed.

Adolescent↗

PubMed1983

Monoclonal antibodies to human chorionic gonadotropin and its beta-subunit.

Using the technique of somatic cell fusion, monoclonal antibodies to human chorionic gonadotropin (hCG) and its beta-subunit were produced. Spleen cells from immunized mice were fused with the myeloma line NS-1 using 50% polyethylene glycol and cultured in a selection medium. A sensitive enzyme immunoassay was performed for antibody screening using immobilized solid-phase antigen and anti-mouse IgG Fab' (rabbit)-beta-D-galactosidase complex. Three double-cloned hybridomas (named 4H10, 4G2 and 1D12) were obtained. Anti-hCG 4H10 antibody reacted with hCG, the alpha-subunit of hCG (alpha-hCG) and human luteinizing hormone (hLH); and anti-hCG 4G2 antibody reacted with hCG and the beta-subunit of hCG (beta-hCG). It was interesting that anti-beta-hCG 1D12 antibody had the capacity to bind with free beta-hCG but not with intact hCG, which suggests that the 1D12 antibody can recognize a determinant site that is unique to beta-hCG. This unique epitope in beta-hCG might be expressed in or near a part which is hidden in the intact hCG molecule which is composed of alpha- and beta-subunits.

Animals↗

PubMed1983

Disappearance of human chorionic gonadotropin following removal of ectopic pregnancy.

A study was undertaken to determine the length of time serum beta-subunit of human chorionic gonadotropin (beta-hCG) could be detected following removal of ectopic pregnancy. Seven patients underwent complete removal of trophoblastic tissue by either salpingectomy or partial resection of the involved fallopian tube. Nine other patients had conservative surgical treatment by either linear salpingostomy or fimbrial expression of the fallopian tube. Serum beta-hCG levels were determined serially in all these patients. The results demonstrate that the initial titer of hCG is a significant factor in determining the length of time that it can be detected in the serum postoperatively. In addition, decreasing titers, conforming to the disappearance curve of hCG, as constructed in this study, are a helpful aid in avoiding further surgery in the group of patients who had a conservative removal of the trophoblastic tissue. Finally, the serum clearance of hCG by radioimmunoassay may take at least up to 24 days after surgery.

Chorionic Gonadotropin↗

PubMed1987

Markers and characteristics of human SCLC cell lines. Neuroendocrine markers, classical tumor markers, and chromosomal characteristics of permanent human small cell lung cancer cell lines.

Permanent human small cell lung cancer (SCLC) cell lines established in our laboratory were investigated for their expression of the enzymatic neuroendocrine markers L-DOPA decarboxylase (DDC), neuron-specific enolase (NSE), and creatine kinase (CK), including its BB isoenzyme (CK-BB), the classical tumor markers carcinoembryonic antigen (CEA), the alpha and beta subunits of human chorionic gonadotropin (alpha-HCG, beta-HCG), and alpha-fetoprotein (alpha-FP), and their chromosomal characteristics. DDC activities were detectable in 5/6 SCLC cell lines and absent in non-SCLC. NSE levels ranged from 160 to 1422 ng/mg soluble protein and were less than 290 ng/mg soluble protein in non-SCLC. Activities of CK and levels of CK-BB clearly distinguished SCLC from non-SCLC with CK activities greater than 1000 munits/mg soluble protein and CK-BB levels greater than 3000 ng/mg soluble protein in SCLC and less than 300 munits/mg soluble protein and less than 2000 ng/mg soluble protein in non-SCLC. CEA was detectable in 5/6 SCLC cell lines but absent in non-SCLC, and its level seemed to correlate with those of DDC, NSE, and CK. One cell line, SCLC-16H, lost some of its neuroendocrine properties and CEA after 1 year of in vitro cultivation. Generally, marker levels were low in fast growing cell lines and high in slow growing cell lines. HCG alpha and beta subunit and alpha-FP were not detectable in SCLC cell lines. All SCLC cell lines examined had near diploid DNA indices and modal chromosome numbers. Double minute chromosomes and homogeneously staining regions were found in 2/5 and 4/5 SCLC cell lines respectively. With respect to chromosomal aberrations, we found a deletion of the short arm of at least one chromosome 3 in all SCLC cell lines (5/5). These data show that SCLC expresses neuroendocrine markers and CEA; CK is the most sensitive marker, and DDC and CEA are the most specific markers for SCLC in vitro; individual marker levels correlate with each other and the in vitro malignancy of SCLC; and SCLC cell lines have relatively uniform chromosomal characteristics. Our results suggest that patients whose tumors have high levels of DDC, NSE, CK-BB, and CEA have a better prognosis than those with low marker levels. This hypothesis could be proved by comparing pairs of patients that are matched for all known prognostic parameters, in particular tumor spread, for their serum and tumor marker levels with respect to the patients' outcome and prognosis.

Carcinoembryonic Antigen↗

PubMed2005

Diagnosis of hydatidiform mole and persistent trophoblastic disease: diagnostic accuracy of total human chorionic gonadotropin (hCG), free hCG {alpha}- and {beta}-subunits, and their ratios.

OBJECTIVE: Human chorionic gonadotropin (hCG) is widely used in the management of hydatidiform mole and persistent trophoblastic disease (PTD). Predicting PTD after molar pregnancy might be beneficial since prophylactic chemotherapy reduces the incidence of PTD. DESIGN: A retrospective study based on blood specimens collected in the Dutch Registry for Hydatidiform Moles. A group of 165 patients with complete moles (of which 43 had PTD) and 39 patients with partial moles (of which 7 had PTD) were compared with 27 pregnant women with uneventful pregnancy. METHODS: Serum samples from patients with hydatidiform mole with or without PTD were assayed using specific (radio) immunoassays for free alpha-subunit (hCGalpha), free beta-subunit (hCGbeta) and 'total' hCG (hCG + hCGbeta). In addition, we calculated the ratios hCGalpha/hCG + hCGbeta, hCGbeta/hCG + hCGbeta, and hCGalpha/hCGbeta. Specificity and sensitivity were calculated and paired in receiver-operating characteristic (ROC) curve analysis, resulting in areas under the curves (AUCs). RESULTS: hCGbeta, hCGbeta/hCG + hCGbeta and hCGalpha/hCGbeta show AUCs ranging between 0.922 and 0.999 and, therefore, are excellent diagnostic tests to distinguish complete and partial moles from normal pregnancy. To distinguish partial from complete moles the analytes hCGbeta, hCG + hCGbeta and the ratio hCGalpha/hCGbeta have AUCs between 0.7 and 0.8. Although hCGalpha, hCGbeta and hCG + hCGbeta concentrations are significantly elevated in patients who will develop PTD compared with patients with spontaneous regression after evacuation of their moles, in predicting PTD, these analytes and parameters have AUCs <0.7. CONCLUSIONS: Distinction between hydatidiform mole and normal pregnancy is best shown by a single blood specimen with hCGbeta, but hCGbeta/hCG + hCGbeta and hCGalpha/hCGbeta are also excellent diagnostic parameters. To predict PTD, hCGalpha, hCGbeta, hCG + hCGbeta and hCGalpha/hCGbeta are moderately accurate tests, although they are not accurate enough to justify prophylactic chemotherapy treatment for prevention of PTD.

Adolescent↗

PubMed2004

A novel human cancer vaccine elicits cellular responses to the tumor-associated antigen, human chorionic gonadotropin beta.

PURPOSE: The oncofetal antigen, human chorionic gonadotropin beta subunit (hCGbeta), is expressed by a number of carcinomas and is a prognostic indicator in renal, colorectal, bladder, and pancreatic cancers. We describe the development of a novel antibody-based dendritic cell (DC)-targeted cancer vaccine capable of eliciting cellular immune responses directed against hCGbeta. EXPERIMENTAL DESIGN: The tumor-associated antigen hCGbeta was coupled genetically to a human anti-DC antibody (B11). The resulting fusion protein (B11-hCGbeta) was evaluated for its ability to promote tumor antigen-specific cellular immune responses in a human in vitro model. Monocyte-derived human DCs from normal donors were exposed to purified B11-hCGbeta, activated with CD40 ligand, mixed with autologous lymphocytes, and tested for their ability to promote hCGbeta-specific proliferative and cytotoxic T-lymphocyte responses. RESULTS: B11-hCGbeta was found to be a soluble, well-defined, and readily purified product that specifically recognized the human mannose receptor via the B11 antibody portion of the fusion protein. B11-hCGbeta functionally promoted the uptake and processing of tumor antigen by DCs, which led to the generation of tumor-specific HLA class I and class II-restricted T-cell responses, including CTLs capable of killing human cancer cell lines expressing hCGbeta. CONCLUSIONS: Although other hCG vaccines have been shown to be capable of eliciting antibody responses to hCGbeta, this is the first time that cellular immune responses to hCGbeta have been induced by a vaccine in a human system. This DC-targeted hCGbeta vaccine holds promise for the management of a number of cancers and merits additional clinical development.

Animals↗

PubMed1999

Expression and characterization of recombinant beta-subunit hCG homodimer.

We have linked two human chorionic gonadotropin (hCG) beta-subunit cDNAs in tandem such that the expressed fusion protein consists of two mature beta-subunits joined through the carboxy terminal peptide of the first beta-subunit. A single glycine residue is inserted between the two subunits in the fusion protein. Chinese hamster ovary (CHO) cells transformed with a clone that contains the fused cDNAs express and secrete a protein that is consistent with it being a beta-hCG homodimer protein. These beta-homodimer molecules can recombine with two free alpha-subunits indicating that both beta-subunits within the homodimer are likely folded in their native conformation. Our data also suggest that the two beta-subunits fold upon each other as a globular protein and do not appear to exist as a simple fusion of two linear beta-subunits. Furthermore, the two beta-monomer subunits in the fusion protein form a stable homodimer that can bind and activate the hLH/CG receptor specifically. Recombination of the fusion protein with alpha-subunits appears to favor an arrangement where two alpha-subunits combine with a single molecule of the fusion protein. The recombined molecule consists of four subunits and is comparable to two tethered hCG moieties, which constitutes a hCG dimer. This hormone dimer can bind and activate the hLH/CG receptor with an activity approximating that of native hCG.

Animals↗

PubMed1986

The predictive value of hCG beta subunit levels in pregnancies achieved by in vitro fertilization and embryo transfer: an international collaborative study.

Serial human chorionic gonadotropin (hCG) beta subunit measurements of 300 pregnancies achieved by in vitro fertilization (IVF) were obtained by 15 IVF centers worldwide. Hormonal curves were established for 164 normal singleton pregnancies, 25 normal multiple gestations, 60 chemical pregnancies, 41 first-trimester spontaneous abortions, and 10 ectopic pregnancies. In comparison to the normal singleton pregnancy curve, chemical pregnancies and spontaneous abortions showed statistically lower hCG levels. hCG levels of ectopic pregnancies, compared with normal singleton gestations, were lower from days 7 to 14. It is concluded that beta-hCG determinations of in vitro fertilized pregnancies allow pregnancy diagnosis as early as 7 to 9 days after embryo transfer (ET) and will permit early discrimination between normal and abnormal IVF pregnancies. A single beta-hCG determination on day 9 after ET may discriminate chemical, ectopic pregnancy or impending miscarriage from a normal gestation. An hCG determination on day 17 will predict early normal development of an IVF pregnancy.

Abortion, Spontaneous↗

PubMed1991

Serial monitoring of human chorionic gonadotropin and free beta subunit secretion in ectopic pregnancy.

The diagnosis of ectopic pregnancy (EP) has relied primarily on serial serum sampling for human chorionic gonadotropin (hCG) and timely pelvic ultrasound examinations. We recently described the applicability of free beta hCG, intact hCG ratio (%) to distinguish EP from spontaneous abortion or intrauterine pregnancy and found that 35% of EP were uniquely characterized by ratios greater than 0.10. In the present study, we sought to determine if this altered pattern of free beta subunit and intact hCG secretion when present persisted as the EP progressed and whether this ratio was influenced by estradiol (E2) and progesterone (P4) secretion. Twelve patients with histologically-confirmed EP and ratios greater than 0.10 were studied longitudinally from initial presentation to surgical intervention. Ratios (%) ranged from .10 to .52 and persisted at levels greater than 0.10 throughout the period of monitoring in all patients. Intact hCG, free beta hCG and ratios (%) showed no correlation to E2 or P4 concentrations. These data suggest that ratios greater than 0.10 when present persist throughout gestation in EP and may serve as a marker for early diagnosis of EP. Such patterns of hCG secretion in EP may be secondary to altered placental histology with persistence of histologic patterns characteristic of early gestation.

Biomarkers↗

PubMed1985

Human chorionic gonadotropin and human placental lactogen in extragonadal tumors. An immunoperoxidase study of ten non-germ cell neoplasms.

The immunoperoxidase localization of the alpha and beta subunits of human chorionic gonadotropin (hCG) and of human placental lactogen (hPL) was studied in ten extragonadal nontrophoblastic tumors associated with raised serum levels of one or more of these placental proteins. Three of the tumors were bronchial carcinomas, one was a gastric carcinoma, two were malignant carcinoids (one bronchial and one gastric), two were pancreatic islet cell carcinomas, and two were metastatic carcinomas with an unknown primary site. The maximum alpha subunit serum level was 33,000 ng/ml (gastric carcinoid), the maximum hCG/hCG-beta level was 705,000 ng/ml, and the maximum hPL level was 50 ng/ml (both in the gastric carcinoma). An indirect immunoperoxidase technique and rabbit polyclonal affinity-purified antibodies and peroxidase conjugates were used on formalin-fixed, paraffin-embedded sections. Five blocks (eight cases) or six blocks (two cases) from various sites were obtained from each patient at surgery and/or autopsy. Positive stains for hCG/hCG-beta were seen in six of seven tumors (25/37 blocks) with raised levels, for the alpha subunit in nine of nine tumors (30/47 blocks), and for hPL in two of five tumors (4/26 blocks). Only a relatively minor number of the cells were positive, and within the same case, there was considerable site-to-site variation in the number of positive cells. Large bizarre cells contained hCG/hCG-beta as well as the alpha subunit, if it was demonstrated in the same tumor as the beta subunit. Otherwise, the alpha subunit was found in small unremarkable cells. Giant cells that were smaller than those positive for hCG/hCG-beta contained in hPL. In some serial sections, hCG-alpha, hCG/hCG-beta, and hPL were segregated in different cell populations, supporting the concepts of their separate genetic control.

Adenocarcinoma↗

PubMed2006

Gestational trophoblastic diseases: 3. Human chorionic gonadotropin-free beta-subunit, a reliable marker of placental site trophoblastic tumors.

OBJECTIVES: Placental site trophoblastic tumor (PSTT) commonly presents with low and variable concentration of hCG immunoreactivity in serum which can be difficult to differentiate from early stage choriocarcinoma/gestational trophoblastic neoplasm (GTN) or quiescent gestational trophoblastic disease (quiescent GTD). Nontrophoblastic malignancies such as germ cell tumors or other tumors secreting low hCG must also be considered in the differential diagnosis. Because treatments for these conditions are different, a means of differentiating PSTT from other diagnoses is important. We investigate the usefulness of hCG-free beta-subunit to make this discrimination. METHODS: Data collected on cases referred to the USA hCG Reference Service for consultation served as a basis for this retrospective analysis. There were 13 cases with histology proven PSTT and 12 with nontrophoblastic malignancy. hCG-free beta-subunit was measured by immunoassay and reported as a proportion of total hCG (hCG-free beta-subunit(%)). hCG-free beta-subunit(%) results were determined for all histologically proven cases of PSTT and for the nontrophoblastic malignancies. Comparisons of hCG-free beta-subunit(%) were made and compared with those of the 82 choriocarcinoma/GTN cases and 69 quiescent GTD cases. The accuracy of hCG-free beta-subunit(%) to discriminate these malignancies was analyzed by investigating the areas under receiver-operating characteristics curve +/- standard error. RESULTS: hCG-free beta-subunit(%) was the predominant hCG form in cases of PSTT (mean +/- standard deviation, 60 +/- 19%) and nontrophoblastic malignancies (91 +/- 11%), thus discriminating these diagnoses from choriocarcinoma/GTN (9.3 +/- 9.2%) and from quiescent GTD (5.4 +/- 7.8%). The cutoff of >35% free beta-subunit is proposed. At this cutoff, 100% detection at 0% false-positive is achieved. The accuracy of hCG-free beta-subunit(%) for this discrimination is 100 +/- 0%. At a proposed cutoff of >80%, the free beta-subunit test will also distinguish PSTT from nontrophoblastic malignancy, with 77% detection at 23% false-positive or an accuracy of 92 +/- 3.2%. CONCLUSION: Measurement of the proportion hCG-free beta-subunit(%) was found to be useful in the diagnosis of PSTT using proposed cutoff values of >35% and >80%. While this finding needs to be confirmed by larger studies, it would be reasonable to measure hCG-free beta-subunit(%) whenever the diagnosis of PSTT is considered.

Choriocarcinoma↗

PubMed1997

Regulation of the human chorionic gonadotropin alpha- and beta-subunit promoters by AP-2.

Production of the placental hormone, chorionic gonadotropin (CG), increases dramatically as cytotrophoblasts fuse to form syncytiotrophoblasts. The CG alpha- and beta-promoters are both responsive to cAMP, although the kinetics of cAMP stimulation are different. In an effort to understand the mechanisms of coordinate induction of these genes, AP-2 binding sites were identified in the promoter regions of the alpha and CGbeta genes. AP-2 bound to the upstream regulatory element (-186 to -156 base pairs (bp)) in the alpha-promoter and to several different regions of the CGbeta promoter, including footprints 2 and 4B (FP2, -311 to -279 bp; FP4B, 221 to -200 bp). AP-2 antibodies induced supershifts of these complexes, confirming the identity of the protein-DNA complex. In JEG-3 cells, which contain abundant AP-2, mutations in these CGbeta AP-2 sites reduced basal activity and decreased cAMP stimulation. In AP-2-deficient Hep-G2 cells, co-transfection of AP-2 stimulated expression of the CGbeta promoter 10-20-fold, and the alpha-promoter was induced by 3-6-fold. Mutations that eliminate AP-2 binding to CGbeta FP4B reduced AP-2 stimulation by more than 80%, whereas mutations in FP2 reduced AP-2 stimulation by less than 50%. Analyses of AP-2 mutants revealed a requirement for the DNA binding/dimerization domain and the amino-terminal proline-rich and acid-rich transactivation domains for stimulation of the CGbeta promoter. Primary cultures of placental cytotrophoblasts were differentiated into syncytiotrophoblasts in vitro to examine AP-2 expression by reverse transcriptase-polymerase chain reaction. AP-2 mRNA levels increased by day 2 and continued to rise in parallel with a marked increase in alpha and CGbeta gene expression. We conclude that both the alpha and CGbeta promoters contain binding sites for AP-2 and suggest that this transcription factor provides a mechanism for coordinating the induction of these genes during placental cell differentiation.

Cell Nucleus↗

PubMed1980

alpha-Fetoprotein, carcinoembryonic antigen, human chorionic gonadotropin and its beta subunit in metastatic choriocarcinoma: short-term follow-up and determinations of resistance during chemotherapy.

Serum levels of alpha fetoprotein (AFP), carcinoembryonic antigen (CEA), human chorionic gonadotropin (hCG) and its beta subunit (beta-hCG) were measured during the therapy of a choriocarcinoma with lung metastases. All AFP determinations were in the normal range. The CEA levels showed a correlation with the radiologically confirmed development of lung metastases. A rise of hCG during the first 2--6 days to 177.3--407.5% of the initial level and a descent to 17.9--33.7% of the initial level at the 10th day of therapy were typical behavioral patterns associated with tumor sensitivity. The onset of tumor resistance against the chemotherapeutic preparation used was evident within 10 days after therapy. A small rise, a slight fall below the initial value, and then a rapid increase to above the initial level were typical parameters. With established tumor resistance there was an autonomous unremitting increase of hCG activity. Short-term follow-up to hCG in intervals of 2 days at least for over a period of 10 days are deemed advisable for early detection of resistance toward the particular chemotherapeutic preparation used.

Adult↗

PubMed2007

Single chain human chorionic gonadotropin, hCGalphabeta: effects of mutations in the alpha subunit on structure and bioactivity.

The strategy of translationally fusing the subunits of heterodimeric proteins into single chain molecules is often used to overcome the mutagenesis-induced defects in subunit interactions. The approach of fusing the alpha and beta subunits of human Chorionic Gonadotropin (hCG) to produce a single chain hormone (phCGalphabeta) was used to investigate roles of critical residues of the alpha subunit in hormone receptor interaction and biological activity. The alpha subunit was mutated using PCR-based site-directed mutagenesis, fused to the wild type beta subunit and the fusion protein was expressed using Pichia pastoris expression system. Following partial purification, the mutant proteins were extensively characterized using immunological probes, receptor assays, and in vitro bioassays. The mutation hCGalpha P38A, which disrupts subunit interaction in the heterodimeric molecule, produced a fusion molecule exhibiting altered subunit interactions as judged by the immunological criteria, but could bind to the receptor with lower affinity and elicit biological response. Mutation of hCGalpha T54A disrupting the glycosylation at Asparagine 52, believed to be important for bioactivity, also yielded a biologically active molecule suggesting that the glycosylation at this site is not as critical for bioactivity as it is in the case of the heterodimer. The fusion protein approach was also used to generate a superagonist of hormone action. Introduction of four lysine residues in the Loop 1 of the alpha subunit led to the generation of a mutant having higher affinity for the receptor and enhanced bioactivity. Immunological characterization of single chain molecules revealed that the interactions between the subunits were not identical to those seen in the heterodimeric hormone, and the subunits appeared to retain their isolated conformations, and also retained the ability to bind to the receptors and elicit response. These data suggest the plasticity of the hormone-receptor interactions.

Antibodies, Monoclonal↗

PubMed2004

Disulfide bond rearrangement during formation of the chorionic gonadotropin beta-subunit cystine knot in vivo.

The intracellular kinetic folding pathway of the human chorionic gonadotropin beta-subunit (hCG-beta) reveals the presence of a disulfide between Cys residues 38-57 that is not detected by X-ray analysis of secreted hCG-beta. This led us to propose that disulfide rearrangement is an essential feature of cystine knot formation during CG-beta folding. To test this, we used disulfide bond formation to monitor progression of intracellular folding intermediates of a previously uncharacterized protein, the CG-beta subunit of cynomolgous macaque (Macaca fascicularis). Like its human counterpart hCG-beta with which it shares 81% identity, macaque (m)CG-beta is a cystine knot-containing subunit that assembles with an alpha-subunit common to all glycoprotein hormone members of its species to form a biologically active heterodimer, mCG, which, like hCG, is required for pregnancy maintenance. An early mCG-beta folding intermediate, mpbeta1, contained two disulfide bonds, one between Cys34 and Cys88 and the other between Cys38 and Cys57. The subsequent folding intermediate, mpbeta2-early, was represented by an ensemble of folding forms that, in addition to the two disulfides mentioned above, included disulfide linkages between Cys9 and Cys57 and between Cys38 and Cys90. These latter two disulfides are those contained within the beta-subunit cystine knot and reveal that a disulfide exchange occurred during the mpbeta2-early folding step leading to formation of the mCG-beta knot. Thus, while defining the intracellular kinetic protein folding pathway of a monkey homologue of CG-beta, we detected the previously predicted disulfide exchange event crucial for CG-beta cystine knot formation and attainment of CG-beta assembly competence.

Alkylation↗

PubMed1988

Production of beta-human chorionic gonadotropin by germ cell tumors in vivo and in vitro.

Production of the beta-subunit of human chorionic gonadotropin (beta-hCG) by human germ cell tumors was studied in surgical specimens, cultured cells and xenografted tumors. beta-hCG was identified most frequently in the syncytiotrophoblastic and intermediate trophoblastic components of choriocarcinoma, and it was also detected in syncytiotrophoblastic giant cells, occasionally in association with embryonal carcinoma, and less frequently with yolk sac tumor, seminoma and dysgerminoma. Our experimental data suggest that beta-hCG production by syncytiotrophoblastic giant cells in association with embryonal carcinoma is a result of trophoblastic differentiation of embryonal carcinoma. Moreover, it was proved that the production of beta-hCG by human embryonal carcinomas is regulated by more factors than is the case for human choriocarcinomas.

Adult↗

PubMed1995

Combination assay of urinary beta-core fragment of human chorionic gonadotropin with serum tumor markers in gynecologic cancers.

Ectopic production of the immunoreactive beta-subunit of human chorionic gonadotropin (IR-hCG beta) by gynecologic malignancies has been well recognized, but IR-hCG beta has not yet been established as a clinically useful tumor marker, except for germ cell tumors. We measured the concentrations of IR-hCG beta-related molecules, intact hCG, free hCG beta, and beta-CF, in the sera and urine of patients with various gynecologic cancers (cervical, endometrial, and ovarian cancers) to assess their clinical usefulness as a tumor marker in comparison with serum tumor markers such as CEA, SCC, CA125, and CA19-9. The highest incidence of IR-hCG beta was obtained in the assay for beta-CF in the urine, with positive rates of 47.7% (94 of 197) for cervical, 37.8% (14 of 37) for endometrial, and 84.4% (38 of 45) for ovarian cancers with a cut-off value of 0.2 ng/mg of creatinine. In cervical cancer, there was no significant correlation between the concentrations of urinary beta-CF and serum SCC, and 57.9% (114 of 197) of the patients were detected by the combination assay of these tumor markers. Serial determination in 22 cervical cancer patients with elevated urinary beta-CF level prior to therapy showed that its level decreased after successful treatment, but 4 of 5 patients with persistent or recurrent disease had elevated levels of urinary beta-CF. All of the ovarian cancer patients examined were detected by the combination assay of urinary beta-CF and serum CA125. The levels of urinary beta-CF showed little correlation with those of the serum tumor markers, indicating the usefulness of the combination assay of urinary beta-CF with serum tumor markers for detecting cervical and ovarian cancers.

Biomarkers, Tumor↗

PubMed1985

Human chorionic gonadotropin in normal, inflammatory, and carcinomatous gastric tissue.

Tissues from 12 patients with gastric ulcers, 50 patients with gastric carcinoma, and 2 normal subjects who died suddenly were examined immunohistochemically with antiserum against the beta-subunit of human chorionic gonadotropin. Human chorionic gonadotropin-beta-immunoreactive cells were present in the neck portion of the pyloric and pseudopyloric glands of normal and inflammatory gastric tissue. Gastric cancers located in the antrum-pylorus and the cardia were frequently associated with human chorionic gonadotropin immunoreactivity. These findings indicate that human chorionic gonadotropin-producing cells normally exist in the gastric mucosa, especially in the pylorus. It is speculated that normal human chorionic gonadotropin-producing cells may give rise to cancer in certain cases.

Adenocarcinoma↗