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Cytosolic levels of neuron-specific enolase in squamous cell carcinomas of the lung.

To study the behavior and possible correlations of neuron-specific enolase (NSE) with other clinicobiological parameters, we measured the cytosolic levels of this marker by means of an immunoradiometric assay (IRMA) in 95 squamous cell lung carcinoma samples. We also analyzed the levels of pS2, tissue-type plasminogen activator (t-PA), hyaluronic acid (HA), free beta subunit of human chorionic gonadotropin (beta-HCG), CYFRA 21.1 and CA 125 in cytosol. On the cell surface we analyzed the concentrations of epidermal growth factor receptor (EGFR), HA, erbB-2 oncoprotein, CD44s, CD44v5 and CD44v6. Other parameters considered were clinical stage, lymph node involvement, histological grade (HG), ploidy and the cellular S-phase fraction measured by flow cytometry on nuclei obtained from fresh tissues. In the 95 squamous cell carcinomas the cytosolic levels of NSE varied from 4.5 to 2235 ng/mg protein (median: 267) and were significantly higher (p < 0.001) than those observed in 38 samples of normal pulmonary tissue obtained from the same patients (range: 56-657; median: 141.5). When classifying tumors according to the different parameters analyzed, we observed that the levels of NSE were higher in aneuploid than in diploid cases (p = 0.046) and in those that were HG3 than in those that were HG2 (p < 0.001). Tumors with high NSE levels (> 422 ng/mg protein; 75th percentile) were more likely to have high S-phase values (p = 0.012) and were more frequently aneuploid (p = 0.038) and HG3 (p < 0.001) than those with low levels of NSE (< 180 ng/mg protein; 25th percentile). These results lead us to the following conclusions: 1) the cytosolic concentrations of NSE are significantly higher in squamous cell carcinomas than in healthy pulmonary tissue, and 2) the cytosolic concentrations of NSE are not correlated with clinical stage or nodal involvement. However, in our study higher levels of the enzyme were statistically correlated with aneuploidy, histological grade 3 and S-phase. This may explain its association with poorer outcome and progression, but also the more favorable response of tumors with elevated NSE to chemotherapy, as suggested by other groups.

Adult↗

Liver metastases of gestational trophoblastic tumor.

A retrospective study was conducted to determine if a chemotherapy regimen incorporating cis-platinum, etoposide, and actinomycin D (PEA) was associated with an outcome different from that of the standard triple regimen of methotrexate, actinomycin D, and chlorambucil (MAC) in patients with gestational trophoblastic tumor and liver metastases. Subjects were treated at the King Faisal Specialist Hospital Gestational Trophoblastic Center (KFSH-GTC) between January 1980 and December 1990. Of 19 patients with gestational trophoblastic tumor and liver metastases, 6 received MAC chemotherapy, and 8 received PEA. Five patients were terminally ill and received palliative treatment only. Treatment outcome was measured by beta-subunit human chorionic gonadotropin assay (beta-HCG) and by imaging studies which included ultrasound, computerized axial tomography, and/or magnetic resonance imaging. Durable remission was obtained in 5 of 8 (62.5%) PEA-treated patients and none of 6 MAC-treated patients. There was no difference in risk status or World Health Organization (WHO) prognostic score between the two groups. We conclude that PEA is a relatively effective chemotherapy regimen in the treatment of gestational trophoblastic tumor with liver metastases, and it may be worthy of consideration for prospective clinical trials.

Adult↗

[Diagnosis and management of gestational trophoblastic tumor with liver metastases].

OBJECTIVE: To evaluate management options and clinical prognosis for women presenting gestational trophoblastic tumor (GTT) with liver metastases. METHODS: We retrospectively analyzed sixteen GTT patients with liver metastases treated in the Peking Union Medical College (PUMC) hospital from 1985 to 1998. All were treated with 5-FU combined chemotherapy or EMA/CO regimen. Eight of them received hepatic artery infusion chemotherapy. Treatment outcome was measured by beta subunit human chorionic gonadotropin assay (beta-hCG) and by imaging studies which included ultrasound and computerized tomography. RESULTS: Of 16 cases, 4 achieved complete remission; biochemical remission was obtained in 2 patients who were alive with residual tumor; 10 patients died of the disease. The overall survival rate was 37.5% (6/16). CONCLUSIONS: The outcome for women presenting with liver metastases from GTT is poor. Early diagnosis and prompt initiation with vigorous multi-agent chemotherapy given through multi-routes are emphasized for improving the treatment outcome.

Adult↗

Human chorionic gonadotropin and free beta subunits stimulate phospholipid methylation in intact rat Leydig cells.

The effect of human chorionic gonadotropin (hCG) on intact Leydig cell phospholipid methylation was studied. Hormonal stimulation of rat Leydig cells increased the incorporation of [methyl-3H]methionine into phospholipids threefold. This effect was observed after 10 minutes of incubation time and was time and dose dependent with a maximal stimulation at 67 ng/ml of hCG. In the presence of hCG, 3H-labeled methyl groups were preferentially incorporated into phosphatidyl-N-monomethylethanolamine. This effect of hCG was not reproduced by dibutyryl cyclic adenosine monophosphate (cAMP), cholera toxin, or forskolin. Purified hCG beta subunit but not hCG alpha subunit had stimulatory activity on Leydig cell phospholipid methylation. We conclude that luteinizing hormone (LH)/hCG stimulates specifically Leydig cell phospholipid methylation, because LH-releasing hormone or [Arg8]-vasopressin did not modify these reactions. We postulate that these reactions are occurring at a cellular level that involves hormone-receptor interaction. It is also suggested that this biological response involves hCG beta subunit receptor interaction and does not require cAMP synthesis.

Animals↗

Diagnosis and management of ectopic pregnancy.

Ectopic pregnancy is a high-risk condition that occurs in 1.9 percent of reported pregnancies. The condition is the leading cause of pregnancy-related death in the first trimester. If a woman of reproductive age presents with abdominal pain, vaginal bleeding, syncope, or hypotension, the physician should perform a pregnancy test. If the patient is pregnant, the physician should perform a work-up to detect possible ectopic or ruptured ectopic pregnancy. Prompt ultrasound evaluation is key in diagnosing ectopic pregnancy. Equivocal ultrasound results should be combined with quantitative beta subunit of human chorionic gonadotropin levels. If a patient has a beta subunit of human chorionic gonadotropin level of 1,500 mIU per mL or greater, but the transvaginal ultrasonography does not show an intrauterine gestational sac, ectopic pregnancy should be suspected. Diagnostic uterine curettage may be appropriate in patients who are hemodynamically stable and whose beta subunit of human chorionic gonadotropin levels are not increasing as expected. Appropriate treatment for patients with nonruptured ectopic pregnancy may include expectant management, medical management with methotrexate, or surgery. Expectant management is appropriate only when beta subunit of human chorionic gonadotropin levels are low and declining. Initial levels determine the success of medical treatment. Surgical treatment is appropriate if ruptured ectopic pregnancy is suspected and if the patient is hemodynamically unstable.

Abortifacient Agents, Nonsteroidal↗

Isolation of a 48.5-kDa membrane protein from Pseudomonas maltophilia which exhibits immunologic cross-reaction to the beta-subunit of human chorionic gonadotropin.

In separate studies we have shown that Pseudomonas maltophilia (American Type Culture Collection 13637) possesses an immunoglobulin Fc-binding protein. We have found that this protein prevents the application of immunoassays using monoclonal antibodies to study possible production of a CG-like material by this bacteria. Employing an immunoglobulin saturation technique to block this protein as well as a zwitterion detergent membrane solubilization technique, we now report the isolation of a membrane protein from Pseudomonas maltophilia which shows immunological relationships to the beta-subunit and carboxyl tail of human pregnancy CG. This pseudomonas immunoreactive material produced dose-response curves in the following CG immunoassays: 1) a polyclonal rabbit anti-CG equilibrium assay, 2) carboxyl tail CG equilibrium assay, and 3) two CG equilibrium assays using monoclonal antibodies. The pseudomonas CG-like protein did not react in equilibrium assays for human TSH, human LH, or free alpha-subunit of CG. The pseudomonas CG-like protein was purified by affinity chromatography. The purified protein showed only 0.25% cross-reaction with pregnancy CG in the monoclonal antibody equilibrium assays. Furthermore, the purified protein showed no binding to rat testicular CG/LH receptors, but showed avid binding to the pseudomonas CG-binding protein previously described by Richert and Ryan. The pseudomonas protein showed no binding to Concanavalin-A, which avidly binds pregnancy CG. When assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting, this protein had a mol wt of 48,500 daltons, which is larger than the mol wt of the unglycosylated beta-subunit of pregnancy CG. We conclude that pseudomonas contain a protein that has partial homology to the beta-subunit of pregnancy CG. This material does not bind to mammalian CG receptors, but does bind to a pseudomonas CG-binding site. The latter suggests it has a function, as yet unknown, in pseudomonas.

Bacterial Proteins↗

Differential occurrence of free beta and free alpha subunits of human chorionic gonadotropin (hCG) in pregnancy sera.

Levels of hCG alpha beta dimer, free alpha-subunit and free beta-subunit were measured in pregnancy sera. Dimer and free alpha were quantitated by radioimmunoassays (RIAs) using specific polyclonal antisera. Free beta was quantitated both by monoclonal anti-beta RIA and by polyclonal anti-beta RIA following the complete adsorption of cross-reacting hCG by immobilized alpha-antisera. Consistent with the findings of other laboratories, hCG levels in pregnancy sera peaked at around 10 weeks after the last menstrual period (post LMP), and declined thereafter. Free alpha levels rose as hCG levels declined and accounted for 30-40% of total serum alpha in the third trimester. Although free beta accounted for only a small proportion of the total beta-subunit at the time of the hCG peak and thereafter (2.4-3.6%), in early pregnancy serum samples, 4-6 weeks post LMP, when hCG was generally first detected, an average of 16% free beta was detected. At this time, the higher the hCG level (20-2000 ng/ml), the lower the percent free beta (54-3%). Thus, the free beta portion started high and declined prior to the hCG peak; the free alpha portion increased thereafter. To explain these findings, we propose a two phase regulation of hCG dimer formation. Up to the time of the hCG peak, supplies of alpha-subunit are limiting (hence the presence of free beta). Thereafter, beta-subunit levels drop, restricting dimer formation and leaving uncombined alpha.

Chorionic Gonadotropin↗

Monoclonal antibody specific to the beta subunit of human chorionic gonadotropin (hCG) and capable of agglutinating hCG-coated red blood cells.

Spleen cells of BALB/c mice immunized with human chorionic gonadotropin (hCG) were fused with NS-1 mouse myeloma cells. A hybrid cell line, clone PE4 secreting monoclonal antibody (MAb) to hCG was isolated by simultaneous screening with both a radioimmunoassay (RIA) and a hemagglutination inhibition assay (HAI). With the aid of the double-antibody radioimmunoassay, it was established that PE4-MAb recognizes the beta-subunit of hCG. It shows an affinity constant of 0.4 X 10(10) L/M and cross-reactivity of 0.1% to other related human glycopeptide hormones. PE4-MAb agglutinates sheep red blood cells coated with hCG and can be used in an HAI assay for hCG. Dual screening procedures have, thus, led to a monoclonal antibody showing high sensitivity in two different assays, and hence useful for the qualitative detection and quantitative determination of hCG by both RIA and HAI methods.

Animals↗

Immunogenicity of three C-terminal synthetic peptides of the beta subunit of human chorionic gonadotropin and properties of the antibodies raised against 45-amino acid C-terminal peptide.

Immunological studies were carried out in rhesus monkeys and rabbits on three C-terminal synthetic peptides of beta-hCG (115-145; 111-145 and 101-145) after conjugating these to tetanus toxoid (TT). The immunogenicity of the peptide conjugates was comparatively poorer with reference to Pr-beta-hCG-TT conjugates at similar doses and immunization schedule. Amongst the three peptides, the best response was obtained with the 45-amino acid c-terminal peptide (45-CTP; 101-145). The anti-45-CTP recognized native hCG and was devoid of cross-reaction with hLH. hCG-induced testosterone production by mouse Leydig cells was inhibited by anti-45-CTP antiserum, although its neutralization capacity decreased more rapidly upon dilution than anti-beta-hCG sera of comparable titres. Immune complexes formed by the anti-45-CTP with hCG had a lower sedimentation value than those formed by anti-beta-hCG antisera with hCG, suggesting the presence of a limited number of immuno-determinant regions in the 45-amino acid C-terminal synthetic peptide.

Amino Acids↗

Successful cure of dermatomyositis after treatment of nonseminomatous testicular cancer.

Although the association between dermatomyositis and cancer is well recognized, there have been a limited number of reports of dermatomyositis associated with testicular cancer. We report the case of a 31-year-old man who was diagnosed with dermatomyositis. Because the patient's serum levels of alpha-fetoprotein and human chorionic gonadotropin beta subunit were elevated, the patient was referred to our department. Physical examination revealed an induration (2 cm x 2 cm) in the left testis and the patient was diagnosed with stage IIIB left testicular cancer. A left high orchidectomy was then performed, and pathological examination revealed embryonal carcinoma. The patient was started on a systemic chemotherapeutic (etoposide, ifosfamide and cisplatin; VIP) regimen. After the third chemotherapy session, metastases had completely disappeared, the serum levels of alpha-fetoprotein and human chorionic gonadotropin beta subunit had normalized and the dermatomyositis symptoms had improved. Cancer is known to be a trigger of dermatomyositis. This case illustrates the importance of palpation of the testes in young patients with dermatomyositis.

Adult↗

Malignant transformation of nontrophoblastic cells is associated with the expression of chorionic gonadotropin beta genes normally transcribed in trophoblastic cells.

The beta subunit of human chorionic gonadotropin (hCGbeta) is encoded by four nonallelic CGbeta genes. An assay was developed for distinguishing type I CGbeta allelic genes beta7 and beta6, which possess a GCC codon corresponding to an alanine at position 117 of hCGbeta, from type II CGbeta genes beta8, beta5, and beta3 and its allele beta9, which possess a GAC codon corresponding to an aspartic acid at the same position. In normal trophoblast, hCGbeta is encoded by type II CGbeta genes, whereas normal nontrophoblastic tissues of differing histological origin (breast, prostate, skeletal muscle, bladder, adrenal glands, thyroid, colon, and uterus) express only type I CGbeta genes. We studied the expression of CGbeta genes in 86 tumor specimens collected from patients with breast, bladder, prostate, and thyroid cancer and found that up to 61% of these nontrophoblastic tumors expressed type II CGbeta genes. Experiments performed on tumor tissues and their normal counterparts confirmed that the malignant transformation of nontrophoblastic cells is associated with the expression of type II CGbeta genes. These findings provide the basis for a simple test (the CG117 assay) that may be useful for the diagnosis of the most frequent malignancies.

Cell Line↗

High initial values of beta-subunits of human chorionic gonadotropin in ovum donation pregnancies indicate better implantation.

Fifty-five patients were treated by ovum donation, and a control group of 165 patients underwent IVF. The number of pregnancies obtained were 28 and 25, respectively. The initial beta-hCG values, as well as the PRs and implantation rates, in the ovum donation series were significantly higher than those of the IVF series. The clinical significance and potential application of these observations are discussed.

Chorionic Gonadotropin↗

Assignment of disulfide bonds in the beta subunit of human chorionic gonadotropin.

The assignment of five disulfide bonds in the alpha subunit of human chorionic gonadotropin (hCG) using partial reduction and S-[14C]carboxymethylation has been reported earlier (Mise, T., and Bahl, O. P. (1980) J. Biol. Chem. 255, 8516-8522). Employing a similar approach, we have determined the locations of six disulfide bonds in hCG-beta. Two partially reduced and S-[14C]carboxymethylated hCG-beta derivatives, DS1.4-hCG-beta and DS3.4-hCG-beta in which on the average 1.4 and 3.4 disulfide bonds were modified, respectively, were prepared. The 14C-labeled derivatives were then completely reduced and S-carboxymethylated with nonradioactive iodoacetic acid and subjected to hydrolysis with trypsin. The radioactive peptides were purified by gel filtration and high voltage paper electrophoresis. The tryptic peptides containing two or more S-[14C]carboxymethylcysteines were further degraded using various proteolytic enzymes such as thermolysin, carboxypeptidase A and Y, cathespin C, and subtilisin to obtain individual S-[14C]carboxymethylcysteine-containing peptides. From the specific radioactivities of S-[14C]carboxymethylcysteines in DS3.4-hCG-beta, four out of six disulfide bonds, 9-90, 26-110, 34-88, and 93-100 were assigned. Similar data from DS1.4-hCG-beta gave the locations of the other two disulfide bonds, 23-72 and 38-57, while confirming the locations of four disulfide bonds derived from the radioactivity distribution in DS3.4-hCG-beta. Thus, all six disulfide bonds in hCG-beta have been located. The results of controlled reduction and S-[14C]alkylation also indicate that disulfide bond 93-100 is the most reactive, followed by disulfide bond 26-110, and that the least reactive among all is 34-88.

Amino Acid Sequence↗

Molecular beacon reverse transcription-PCR of human chorionic gonadotropin-beta-3, -5, and -8 mRNAs has prognostic value in breast cancer.

BACKGROUND: The beta-subunit of human chorionic gonadotropin (hCG) is encoded by four genes, of which expression of the hCGbeta-3, -5, and -8 genes could have prognostic value in breast cancer. METHODS: Applying a new, modified Molecular Beacon reverse transcription-PCR assay, we investigated the prognostic value of the hCGbeta-3, -5, and -8 gene transcripts in 129 sporadic unilateral breast cancer samples from patients with a median follow-up of 62.3 months. RESULTS: Expression of hCGbeta-3, -5, -8 was significantly (P = 0.020) associated with relapse-free survival (RFS). In multivariate survival analysis, hCGbeta-3, -5, and -8 maintained prognostic value for RFS, with high expression predicting shorter RFS (P = 0.015; hazard ratio, 2.25; 95% confidence interval, 1.17-4.34). Only 1 of 24 (4%) node-negative patients with low hCGbeta-3, -5, -8 expression relapsed, in contrast to 7 of 26 (27%) patients with high expression (P = 0.046). CONCLUSIONS: Expression of hCGbeta-3, -5, -8, which differ by only one nucleotide from other hCGbeta genes, can be assessed by our modified Molecular Beacon assay in breast cancer tissues. Expression of hCGbeta-3, -5, -8 has independent, prognostic value for RFS in breast cancer and may help identify node-negative patients with poor prognosis.

Actins↗

Phase I clinical trial of a World Health Organisation birth control vaccine.

A birth control vaccine incorporating a synthetic peptide antigen representing the aminoacid sequence 109-145 of the C-terminal region of the beta subunit of human chorionic gonadotropin (hCG-beta) was submitted to a phase 1 clinical trial. Thirty surgically sterilised female volunteers, divided into five equal groups for different vaccine doses, received two intramuscular injections six weeks apart. Over a six-month follow-up there were no important adverse reactions, and potentially contraceptive levels of antibodies to hCG developed in all subjects. In the highest vaccine dose group, the results gave promise of a contraceptive effect of six months' duration.

Adult↗

Fibroblast growth factor enhances the transcription and stability of human chorionic gonadotropin beta-subunit messenger ribonucleic acid in Jar choriocarcinoma cells.

In previous studies, we found that basic fibroblast growth factor (bFGF) significantly stimulated the secretion of hCG beta in the Jar choriocarcinoma cell line. In the present study, the effect of bFGF on the steady state hCG beta mRNA level in this cell line was determined. Application of Northern analyses with total RNA isolated from bFGF-stimulated Jar cells revealed that, in a time-dependent manner, the steady state hCG beta mRNA level increased progressively, reaching 4-fold of the control value within 4 h after exposure to bFGF. The observed accumulation was due in part to increased transcription (2.4-fold relative to that in control cultures), as determined by nuclear transcription studies. In addition, bFGF increased the stability of the hCG beta message; the message half-life was increased from approximately 3 h (in control cultures) to greater than 6 h (in bFGF-treated cultures). These data demonstrate that bFGF stimulates hCG beta mRNA accumulation in a complex manner regulated through both transcriptional and posttranscriptional mechanisms.

Actins↗