Ectopic synthesis of pregnancy specific beta 1-glycoprotein (SP1) and placental specific tissue proteins (PP5, PP10, PP11, PP12) in nontrophoblastic malignant tumours. Possible markers in oncology

Identification and validation of a prognostic model based on ferroptosis-associated genes in head and neck squamous cancer

Ferroptosis is that under the action of ferrous iron or ester oxygenase, unsaturated fatty acids highly expressed on the cell membrane are catalyzed to undergo lipid peroxidation, thereby inducing cell death. In this study, we used ferroptosis marker genes to identify 3 stable molecular subtypes (C1, C2, C3) with distinct prognostic, mutational, and immune signatures by consensus clustering; TP53, CDKN2A, etc. Have higher mutation frequencies in the three subtypes. C3 has a better prognosis, while the C1 subtype has a worse prognosis. WGCNA is used to identify molecular subtype-related gene modules.After filting, we obtained a total of 540 genes related to the module feature vector (correlation>0.7).We performed univariate COX regression analysis on these genes, and identified a total of 97 genes (p < 0.05) that had a greater impact on prognosis, including 8 ''Risk" and 89 ''Protective" genes. After using lasso regression, we identified 8 genes (ZNF566, ZNF541, TMEM150C, PPAN, PGLYRP4, ENDOU, RPL23 and MALSU1) as ferroptosis-related genes affecting prognosis. The ferroptosis prognosis-related risk score (FPRS) was calculated for each sample in TCGA-HNSC dataset. The results showed that FPRS was negatively correlated with prognosis.The activated pathways in the PFRS-high group mainly include immune-related pathways and invasion-related pathways. We assessed the extent of immune cell infiltration in patients in our TCGA-HNSC cohort by using the expression levels of gene markers in immune cells. The FPRS-high group had a higher level of immune cell infiltration. We found that the expression of immune checkpoints was significantly up-regulated in the FPRS-low group and the FPRS-high group had a higher probability of immune escape and a lower probability of benefiting from immunotherapy. In this work, we constructed a scoring Ferroptosis-related prognostic model that can well reflect risk and positive factors for prognosis in patients with head and neck squamous cell carcinoma. It can be used to guide individualized adjuvant therapy and chemotherapy for patients with head and neck cancer. Therefore, it has a good survival prediction ability and provides an important reference for clinical treatment.

Integrated Analysis Reveals ENDOU as a Biomarker in Head and Neck Squamous Cell Carcinoma Progression

Background

Head and neck squamous cell carcinoma (HNSCC) is a leading cancer with high morbidity and mortality worldwide. The aim is to identify genes with clinical significance by integrated bioinformatics analysis and investigate their function in HNSCC.

Methods

We downloaded and analyzed two gene expression datasets of GSE6631 and GSE107591 to screen differentially expressed genes (DEGs) in HNSCC. Common DEGs were functionally analyzed by Gene ontology and KEGG pathway enrichment analysis. Protein-protein interaction (PPI) network was constructed with STRING database and Cytoscape. ENDOU was overexpressed in FaDu and Cal-27 cell lines, and cell proliferation and migration capability were evaluated with MTT, scratch and transwell assay. The prognostic performance of ENDOU and expression correlation with tumor infiltrates in HNSCC were validated with TCGA HNSCC datasets.

Results

Ninety-eight genes shared common differential expression in both datasets, with core functions like extracellular matrix organization significantly enriched. 15 genes showed prognostic significance, and COBL and ENDOU serve as independent survival markers in HNSCC. In-vitro ENDOU overexpression inhibited FaDu and Cal-27 cells proliferation and migration, indicating its tumor-suppressing role in HNSCC progression. GSEA analysis indicated ENDOU down-stream pathways like DNA replication, mismatch repair, cell cycle and IL-17 signaling pathway. ENDOU showed relative lower expression in HNSCC, especially HPV-positive HNSCC samples. At last, ENDOU showed negative correlation with tumor purity and tumor infiltrating macrophages, especially M2 macrophages.

Conclusion

This study identified ENDOU as a biomarker with prognostic significance in HNSCC progression.

Embryonic expression patterns of Eukaryotic EndoU ribonuclease family gene endouC in zebrafish

Endou proteins belong to the Eukaryotic EndoU ribonuclease family of enzymes that present high sequence homology with the founding member XendoU domain. The enzymatic activity and three-dimensional structure of some Endou proteins have been previously reported. However, their molecular structure and gene expression patterns during embryogenesis remain to be elucidated. Therefore, we took zebrafish (Danio rerio) endouC as the model to study molecular structure and gene expression dynamics at different developmental stages. Zebrafish endouC cDNA contains 930 base pairs encoding 309 amino acid residues, sharing 27%, 27%, 27%, and 25% identity with that of human, mouse, chicken and frog, respectively. A phylogenetic tree showed that zebrafish EndouA was clustered with vertebrate Endou groups, while zebrafish EndouB and EndouC were found to belong to a unique monophyletic group. Furthermore, the endouC transcript was detected in one-cell embryos, suggesting that it is a maternal gene. While the endouC transcript was only weakly present at early developmental stages, its expression was greatly increased in embryos from 18 to 48 h post-fertilization (hpf) and then decreased after 72 hpf. Finally, endouC was ubiquitously expressed throughout the whole embryo during early embryogenesis, but its expression was enriched in brain, eyes and fin buds from 24 to 96 hpf.

Maternal-fetal conflict, genomic imprinting and mammalian vulnerabilities to cancer

Antagonistic coevolution between maternal and fetal genes, and between maternally and paternally derived genes may have increased mammalian vulnerability to cancer. Placental trophoblast has evolved to invade maternal tissues and evade structural and immunological constraints on its invasion. These adaptations can be co-opted by cancer in intrasomatic selection. Imprinted genes of maternal and paternal origin favour different degrees of proliferation of particular cell types in which they reside. As a result, the set of genes favouring greater proliferation will be selected to evade controls on cell-cycle progression imposed by the set of genes favouring lesser proliferation. The dynamics of stem cell populations will be a particular focus of this intragenomic conflict. Gene networks that are battlegrounds of intragenomic conflict are expected to be less robust than networks that evolve in the absence of conflict. By these processes, maternal-fetal and intragenomic conflicts may undermine evolved defences against cancer.

Epigenetic regulation of human placental function and pregnancy outcome: considerations for causal inference

Epigenetic mechanisms, often defined as regulating gene activity independently of underlying DNA sequence, are crucial for healthy development. The sum total of epigenetic marks within a cell or tissue (the epigenome) is sensitive to environmental influence, and disruption of the epigenome in utero has been associated with adverse pregnancy outcomes. Not surprisingly, given its multifaceted functions and important role in regulating pregnancy outcome, the placenta shows unique epigenetic features. Interestingly however, many of these are only otherwise seen in human malignancy (the pseudomalignant placental epigenome). Epigenetic variation in the placenta is now emerging as a candidate mediator of environmental influence on placental functioning and a key regulator of pregnancy outcome. However, replication of findings is generally lacking, most likely due to small sample sizes and a lack of standardization of analytical approaches. Defining DNA methylation "signatures" in the placenta associated with maternal and fetal outcomes offers tremendous potential to improve pregnancy outcomes, but care must be taken in interpretation of findings. Future placental epigenetic research would do well to address the issues present in epigenetic epidemiology more generally, including careful consideration of sample size, potentially confounding factors, issues of tissue heterogeneity, reverse causation, and the role of genetics in modulating epigenetic profile. The importance of animal or in vitro models in establishing a functional role of epigenetic variation identified in human beings, which is key to establishing causation, should not be underestimated.

Expression of human skin-specific genes defined by transcriptomics and antibody-based profiling

To increase our understanding of skin, it is important to define the molecular constituents of the cell types and epidermal layers that signify normal skin. We have combined a genome-wide transcriptomics analysis, using deep sequencing of mRNA from skin biopsies, with immunohistochemistry-based protein profiling to characterize the landscape of gene and protein expression in normal human skin. The transcriptomics and protein expression data of skin were compared to 26 (RNA) and 44 (protein) other normal tissue types. All 20,050 putative protein-coding genes were classified into categories based on patterns of expression. We found that 417 genes showed elevated expression in skin, with 106 genes expressed at least five-fold higher than that in other tissues. The 106 genes categorized as skin enriched encoded for well-known proteins involved in epidermal differentiation and proteins with unknown functions and expression patterns in skin, including the C1orf68 protein, which showed the highest relative enrichment in skin. In conclusion, we have applied a genome-wide analysis to identify the human skin-specific proteome and map the precise localization of the corresponding proteins in different compartments of the skin, to facilitate further functional studies to explore the molecular repertoire of normal skin and to identify biomarkers related to various skin diseases.

The Lepidopteran endoribonuclease-U domain protein P102 displays dramatically reduced enzymatic activity and forms functional amyloids

Hemocytes of Heliothis virescens (F.) (Lepidoptera, Noctuidae) larvae produce a protein, P102, with a putative endoribonuclease-U domain. In previous works we have shown that P102 is involved in Lepidopteran immune response by forming amyloid fibrils, which catalyze and localize melanin deposition around non-self intruders during encapsulation, preventing harmful systemic spreading. Here we demonstrate that P102 belongs to a new class of proteins that, at least in Lepidoptera, has a diminished endoribonuclease-U activity probably due to the lack of two out of five catalytically essential residues. We show that the P102 homolog from Trichoplusia ni (Lepidoptera, Noctuidae) displays catalytic site residues identical to P102, a residual endoribonuclease-U activity and the ability to form functional amyloids. On the basis of these results as well as sequence and structural analyses, we hypothesize that all the Lepidoptera endoribonuclease-U orthologs with catalytic site residues identical to P102 form a subfamily with similar function.

Placental pseudo-malignancy from a DNA methylation perspective: unanswered questions and future directions

The growing fetus is dependent on adequate placental function for delivery of essential nutrients and oxygen, and for waste removal. The placenta also plays an important protective role; shielding the developing baby from the maternal immune system and adverse environmental exposures. Fundamental to these processes is correct invasion of the decidua and remodeling of maternal vasculature, each of which show remarkable parallels to tumorogenesis, with the obvious exception that the former is usually a tightly controlled process. It is not surprising that these physiological similarities are mirrored in gene expression and epigenetic parallels, many not found in any other aspect of human development. In this perspective, we summarize known DNA methylation similarities between placenta and human tumors, and discuss the implications and knowledge gaps associated with these findings. We also speculate on the potential origin of common DNA methylation features in these two disparate aspects of human physiology.

The tumor marker human placental protein 11 is an endoribonuclease

Human PP11 (placental protein 11) was previously described as a serine protease specifically expressed in the syncytiotrophoblast and in numerous tumor tissues. Several PP11-like proteins were annotated in distantly related organisms, such as worms and mammals, suggesting their involvement in evolutionarily conserved processes. Based on sequence similarity, human PP11 was included in a protein family whose characterized members are XendoU, a Xenopus laevis endoribonuclease involved in small nucleolar RNA processing, and Nsp15, an endoribonuclease essential for coronavirus replication. Here we show that the bacterially expressed human PP11 displays RNA binding capability and cleaves single stranded RNA in a Mn(2+)-dependent manner at uridylates, to produce molecules with 2',3'-cyclic phosphate ends. These features, together with structural and mutagenesis analyses, which identified the potential active site residues, reveal striking parallels to the amphibian XendoU and assign a ribonuclease function to PP11. This newly discovered enzymatic activity places PP11-like proteins in a completely new perspective.

[Significance of serum beta-hCG as a tumor marker for stomach carcinoma]

INTRODUCTION

Recent investigations indicate that in 50% of patients with gastric cancer, beta-hCG-positive cells can be found in the tumour by immunohistochemical investigations. The objective of this study was to investigate how often beta-hCG-immunoreactive gastric carcinomas were accompanied by an elevation in serum beta-hCG, that could have been used as a course control variable.

METHODS

In 54 patients with gastric carcinoma a monoclonal antibody directed against beta-hCG was used for immunohistochemical marking in the APAAP system. The evaluation was graded positive or negative. In parallel, serum beta-hCG was determined preoperatively using an enzyme immunoassay (MEIA). Tumour stage, grading and tumour localization were determinants in the evaluation.

RESULTS

We found that 41% (22 of 54) of the carcinomas induced a positive immunohistochemical response to beta-hCG, regardless of their location in the stomach. In relation to tumour stage, a positive beta-hCG immunoreactivity was apparent in 27% (6/22) of tumours without lymph node or distant metastases (T1-4N0M0), in 54% (7/13) of tumours with lymph node and without distant metastases (T1-4N > or = 1M0) and in 47% (9/35) of tumours with distant metastases. Poorly differentiated tumours (G3-4) were positive in 42% (15/36) and well-differentiated tumors (G1-2) in 39% (7/18) of cases. In only 1 patient was the beta-hCG level in serum elevated, however.

CONCLUSIONS

beta-hCG-Positive gastric carcinomas are found more frequently in advanced tumour stages and poorly differentiated carcinomas. These carcinomas, however, seem not to excrete beta-hCG in sufficient amounts to produce measurable serum values. Therefore, beta-hCG cannot be used a prognostic factor or for course control. The relevance of beta-hCG expression of tumour cells to the patients' prognosis remains obscure.

The development of an enzyme immunoassay for placental tissue protein 17 (PP17) and its clinical significance

We developed an enzyme immunoassay (EIA) for placental protein 17 (PP17) using avidin biotin binding, and measured the serum-PP17 levels of 37 healthy men, 103 nonpregnant women, 48 pregnant women, and 86 patients with gynecologic malignancies. The mean level was 12.8 ng/ml in healthy men and 44.2 ng/ml in nonpregnant women (p < 0.05). The calculated upper limit of normal was 97.8 ng/ml (mean + 2 sigma). The serum PP17 concentration was remarkedly reduced postmenopausally. Pregnant women showed a mean serum level of 19.2 ng/ml, which was significantly lower than that of nonpregnant women. Immunoserological results strongly suggest that PP17 is produced far more in the normal endometrium than in the placentae and decidua. Patients with gynecologic malignancies had obviously lower mean serum PP17 levels (8.3-19.9 ng/ml) than those found in healthy nonpregnant women. Measurement of the serum PP17 concentration might be useful in distinguishing gynecologic malignancies from various normal conditions.

Immunohistochemical and immunoelectron microscopic study of cytochrome P-450 of human fetal livers (P-450HFLa): implications for an onco-feto-placental enzyme

Cytochrome P-450 of human fetal livers (P-450HFLa) was demonstrated by the avidin-biotin immunoperoxidase technique in tissue samples as follows: human fetal organs, adult livers, human and cynomolgus placenta, and gynecologic organs which were obtained from 40 patients with gynecologic malignancies and 32 patients with benign diseases. P-450HFLa was clearly localized in the cytoplasm and membranes of the hepatocytes, and the fact was confirmed by an immunoelectron microscopic examination. In addition, a semiquantitative assay of staining intensity demonstrated that this enzyme tended to decrease with advancing age. These findings suggest that hepatic P-450HFLa synthesis is inversely proportional to age, and that this enzyme is one of the differentiation antigens. P-450HFLa was also detected immunohistochemically in other fetal organs. The present study thus confirms that P-450HFLa is not specific to the liver and is ubiquitous even in the fetus. Marked positive staining for P-450HFLa was demonstrated in villous syncytiotrophoblasts. In contrast, no positive staining was found in the cynomolgus-monkey placenta, unlike the case for many other placental antigens. These findings lead to the tentative conclusion that P-450HFLa is a feto-placental enzyme peculiar to humans. P-450HFLa was demonstrated to occur very frequently in gynecologic malignancies. The mean positivity rate for all gynecologic malignancies was 85%, while the rate was below 25% for benign gynecologic diseases, indicating that P-450HFLa is one of the onco-feto-placental enzymes. The present study thus suggests that this enzyme could be a promising new tumor marker for gynecologic malignancies.

Electron microscopic identification of the intracellular secretion pathway of human G-CSF in a human tumor cell line: a comparative study with a Chinese hamster ovary cell line (IA1-7) transfected with human G-CSF cDNA

Using monoclonal antibodies specific for human granulocyte colony-stimulating factor (G-CSF), intracellular localization of G-CSF in a G-CSF-producing human tumor cell line (CHU-2) and its ultrastructural characters were described and compared with those of a Chinese hamster ovary cell line (IA1-7) transfected with human G-CSF cDNA. The CHU-2 line, which was derived from a poorly differentiated squamous cell carcinoma of the oral cavity, preserved the character of a poorly differentiated squamous cell carcinoma. In the CHU-2 cell line, there were few cells immunohistochemically positive for G-CSF under light microscopic analysis despite the high transcription level of G-CSF cDNA and secretion of G-CSF that were comparable with cDNA-transfected IA1-7 cells. Using electron microscopy, the reaction products were localized mainly in the perinuclear space (PNS) and rough endoplasmic reticula (RER) without dilation of the cisternae, but they were very rarely found in the Golgi complex and not at all in other intracellular organelles. In contrast, most cells were positive for G-CSF in the IA1-7 cell line. Reaction products in this cell line were also demonstrated in the PNS and RER without dilation of the cisternae. These immunohistochemical findings, in conjunction with the results of Western and Northern blot analysis, suggested that G-CSF was secreted via the PNS and RER without intracellular retention.

Identity between the placental protein PP10 and the specific plasminogen activator inhibitor of placental type PAI-2

The highly specific plasminogen activator inhibitor of placental type, PAI-2, occurs in the placenta in a low molecular mass form of 46.6 kDa, and in pregnancy plasma in a (possibly glycosylated) high molecular mass form of 60 kDa. Extensive knowledge is available about the functional properties of PAI-2 as a plasminogen activator inhibitor and about its molecular biology and regulation. Of the several placenta proteins (PP) isolated, one of them, PP10, has a molecular mass of 48 kDa and its occurrence in malignancy and in complications during pregnancy has been the topic of a number of studies, though its properties and physiological significance are unknown. The present findings constitute evidence of immunological identity between PP10 and PAI-2. The sections of the amino acid sequence of PP10 analysed here were found to have identical counterparts in the sequence of the low molecular mass form of PA1-2, but in several preparations PP10 was found to occur in an inactive two-chain form due to cleavage of an Arg-Thr bond, the two peptide chains being linked to each other by a disulphide bridge. The cleavage site is identical to that observed in the reaction between PAI-2 and urokinase. The results make it possible to coordinate and correlate the findings of many separate studies and our own observations on PP10 and PAI-2.

Enzyme immunoassay for placental protein 4 (PP4) and its possible diagnostic significance in patients with genital tract cancer

We have established an enzyme immunoassay for placental protein 4 (PP4), by using avidin-biotin binding reaction, and set its normal range below 10.9 ng/ml (mean + 2 sigma). Throughout the menstrual cycle, the serum PP4 profile was similar to that of serum progesterone. In the follicular and ovulatory phase, PP4 remained relatively low, with the mean levels of 1.5 ng/ml and 1.8 ng/ml, respectively. In the luteal phase, the mean level was 3.2 ng/ml. In normal pregnancy, serum PP4 levels were low irrespective of gestational age, with a mean level of 3.0 ng/ml. There was only one case in which the serum PP4 level over 10.9 ng/ml. Mean serum PP4 levels and the frequencies of elevated serum PP4 levels were respectively 6.3 ng/ml and 11% in patients with benign ovarian neoplasms, 4.7 ng/ml and 6% in patients with endometriosis, and 5.5 ng/ml and 18% in patients with uterine myomata. The frequency of raised PP4 levels was 48% and the mean value was 13.3 ng/ml in patients with endometrial carcinoma, and the values were 44% and 13.4 ng/ml respectively in patients with cervical carcinoma. In patients with ovarian malignancy, the respective values were 15% and 7.0 ng/ml. The results did not relate to clinical stages of disease (FIGO), while the frequencies of elevated serum PP4 in patients with uterine carcinoma was over 40% in stage I diseases. Compared with other tumor markers such as carcino-embryonic antigen (CEA), tissue polypeptide antigen (TPA) and cancer antigen 125 (CA125), PP4 seems to be more promising as a marker of endometrial carcinoma.(ABSTRACT TRUNCATED AT 250 WORDS)

Cloning and expression of a cDNA encoding human placental protein 11, a putative serine protease with diagnostic significance as a tumor marker

The placental protein 11 (PP11) can act as a tumor marker because of its specific association with various forms of cancer. A lambda gt11 cDNA library prepared from human placenta was screened with a polyclonal anti-PP11 antiserum. Out of 10(6) independent clones, only one clone reacted with the anti-PP11 antiserum. The isolated cDNA coded only for the carboxy-terminal part of PP11 and was subsequently used to rescreen a lambda gt10 placental cDNA library. Two cDNA clones out of 10(6) screened were identified encoding the entire protein of 369 amino acids, including a typical hydrophobic signal sequence of 18 amino acids. Expression of the PP11 cDNA coding sequence in Escherichia coli resulted in the synthesis of a protein with the expected size which can be specifically immunoprecipitated with anti-PP11 antiserum. Fractionation experiments revealed that two forms of the protein are present in the bacterial cell: a higher-molecular-weight form of approximately 42 kD in the cytoplasm and a smaller-molecular-weight form of approximately 42 kD in the periplasm. This result indicates that PP11 can be synthesized in E. coli and is process by removal of the hydrophobic signal sequence. Both the placental and the processed recombinant PP11 protein exhibit a protease activity.

Placental proteins in high-grade urothelial neoplasms. An immunohistochemical study of human chorionic gonadotropin, human placental lactogen, and pregnancy-specific beta-1-glycoprotein

We examined the presence of human chorionic gonadotropin (HCG) in 16 low-grade and 47 high-grade urothelial neoplasms, including two cases with trophoblastic-like differentiation. In HCG-positive tumors, the presence of human placental lactogen (HPL) and pregnancy-specific beta-1-glycoprotein (SP-1) also was assessed. HCG immunoreactive cells were found in nine of the 47 high-grade tumors (19%), whereas none of the low-grade tumors were positive for HCG. This hormone was predominantly detected in the most undifferentiated and pleomorphic areas; however, HCG-positive cells also were found in areas of carcinoma in situ and well-differentiated transitional cell carcinoma in two cases. The serum HCG level was increased in two of the four cases studied. HPL and SP-1 immunoreactive cells were observed in seven and five cases, respectively, and it was found that tumors positive for SP-1 also were positive for HPL. Five tumors, including the two with trophoblastic differentiation, contained the three placental proteins. The HPL and SP-1 immunostained cells were usually found in the same areas of the tumor that were positive for HCG, but there was always a lower number of HPL and SP-1 immunoreactive cells than HCG immunoreactive cells. In one case, HPL and SP-1 could be found in areas of well-differentiated transitional cell carcinoma. These findings suggest that the morphologic and functional trophoblastic differentiation in urothelial carcinomas is a progressive phenomenon evolving from transitional cell carcinomas.

Placental protein 12 (PP 12), a decidual protein, in pregnancy complicated by diabetes with retinopathy

Placental protein 12 (IGF-bp/PP 12) is a soluble tissue antigen produced in the decidua. PP 12 was measured in the 3rd trimester of diabetic pregnancy complicated by retinopathy. The mean values of the healthy control group between 28 and 34 and between 35 and 39 weeks gestation were 108 +/- 39 micrograms/l and 124 +/- 47 micrograms/l, respectively. The equivalent values in diabetic pregnancies complicated by retinopathy were 200 +/- 80 micrograms/l and 204 +/- 81 micrograms/l, respectively; both these PP 12 values were significantly (P less than 0.05) above the values in the control group. There was no significant difference between benign and proliferative retinopathy. The increased PP 12 levels in the presence of diabetic retinopathy are probably caused by decidual degeneration.

Establishment and characterization of a human cell strain, KT, with high sensitivity to UV-killing and to cell proliferation inhibition by interferon

We have established a human cell line, designated KT, with high susceptibility to both cell proliferation inhibition by interferon and UV-killing, from a metastatic breast carcinoma. A tumor marker, a pregnancy-specific glycoprotein (Schwangerschaftsprotein 1; SP1), and carcinoma characteristics compatible with ductal carcinoma of the breast were seen in KT cells by electron microscopic observation. KT cells were slightly more resistant to X-ray-induced toxicity than fibroblastic cells, termed KS, from the scalp of the patient. But, KT cells had lower cloning efficiency after UV irradiation than did KS cells: D0 values of 1.5 J/m2 and 7.2 J/m2, respectively. KT cells also appeared more susceptible to human interferon (HuIFN) preparations (alpha, beta, gamma and natural or recombinant) than did KS cells, as measured by cell colony formation ability, proliferation rates, and [3H]deoxythymidine incorporation levels into acid-insoluble cell materials. The sensitivity of KT cells to UV and HuIFN was greater than that of human RSa cells, a cell line with high sensitivity to both agents. KT cells had more capacity for UV-induced DNA-repair replication synthesis than did RSa cells, the capacity being much the same as that of KS cells. There was no significant difference in levels of antiviral activity induced by HuIFN and binding capacity for 125I-labeled IFN-alpha A between KT and KS cells. KT cells appeared refractory to cell proliferation inhibition by tumor necrosis factor (TNF) preparations.

Immunohistochemical study of tissue polypeptide antigen (TPA) and cancer antigen 125 (CA125) in the human and cynomolgus monkey placenta, umbilical cord and decidua

Tissue polypeptide antigen (TPA) and cancer antigen 125 (CA125) were studied immunohistochemically by the avidin-biotin immunoperoxidase technique in human and cynomolgus monkey placentae, membranes, umbilical cords and decidua. In early human placentae, TPA was localized mainly in the cell membranes of villous syncytio- and cyto-trophoblast. The cytoplasm of those trophoblastic cells were weakly stained with TPA. The membrane of basal chorionic trophoblast cells was strongly stained with TPA and the cytoplasm stained weakly. In early cynomolgus placentae, similar immunostaining results were obtained. However, the positive stainings for TPA was more marked in the cytoplasm of villous syncytiotrophoblast and basal chorionic trophoblast, and less marked in the cell membrane of villous cytotrophoblast. In early human and cynomolgus placentae, CA125 was not demonstrated immunohistochemically in the villi and basal chorion. In human and cynomolgus term placentae, the villous syncytiotrophoblast and basal and reflected chorionic trophoblast showed similar immunostaining as the early placentae. In addition, TPA was found in the amniotic epithelium in both sorts of placentae. TPA was not detected immunohistochemically in the umbilical cord and decidual cells. While weakly positive stains for CA125 were observed in decidual cells, CA125 was localized mainly in the membrane and cytoplasm of amniotic epithelium in both human and cynomolgus term placentae. TPA and CA125 are thus oncoplacental antigens and the monkey could serve as a model for their investigation.

Serum levels of six tumor markers in patients with benign and malignant gynecological disease

We studied the pretreatment serum levels of 6 tumor markers in gynecological patients with and without malignant disease. The tumor markers were carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA), ferritin, Schwangerschaftsprotein 1 (SP1), Schwangerschaftsprotein 3 (SP3) and cancer antigen 125 (CA125). The results were as follows: (1) Serum CA125 and TPA levels were raised in 81% and 57% of patients with ovarian serous cystadenocarcinoma; CEA and SP3, in 52% and 43% respectively of patients with ovarian mucinous cystadenocarcinoma; CA125, TPA and SP3, in 76%, 48% and 48% respectively of patients with other ovarian malignancies; and TPA and SP3, in 56% and 40% respectively of patients with endometrial carcinoma. (2) Serum levels of TPA, ferritin and CA125 were more often raised with advancing stages of malignant disease. (3) Serum TPA levels were elevated in 55% of patients with stage I endometrial carcinoma, and serum SP3 levels were elevated in 35% of patients with a stage I malignant ovarian neoplasm and in 45% of patients with endometrial carcinoma. (4) One of the 6 tumor markers showed a raised level in 84% of patients with gynecologic malignancy as against 56% in those with benign gynecologic diseases.

Placental protein 10: levels in benign and malignant ovarian cyst fluids and pleural exudates

Placental protein 10 (PP10) was measured in benign (n = 47) and malignant (n = 10) ovarian cyst fluids and in pleural fluid specimens from 19 patients with pleural metastases of various carcinomas (n = 15) or infectious pleurisy (n = 4). PP10 was found in 9 out of 18 follicular or luteal cyst fluids (range 2.0-42.0 micrograms/l) and in 24 out of 29 benign ovarian tumours (range 2.6-38.0 micrograms/l). Nine out of ten malignant ovarian cyst fluids contained detectable PP10 (range 4.0-55.2 micrograms/l). PP10 was found in all the pleural fluids from 15 patients with metastatic bronchial, pulmonary, breast or pancreatic carcinomas (range 5.1-100.2 micrograms/l), as well as from four patients with pleurisy (range 5.0-28.6 micrograms/l). Our results indicate that PP10 is tumour-associated, but not tumour-specific.

Placental protein 10 (PP10) in the serum of patients with trophoblastic and nontrophoblastic gynaecological tumours

Serum levels of placental protein 10 (PP10) were measured by radioimmunoassay in patients with trophoblastic (n = 23) and non-trophoblastic (n = 122) gynaecological tumours before, during and after treatment. Elevated levels (greater than 2.0 micrograms/l) were found in 96% of patients with an untreated trophoblastic tumour, and in 22%, 20% and 12% of patients with endometrial, cervical and ovarian carcinoma, respectively. After treatment the levels fell in patients with trophoblastic disease. Although PP10 may be tumour-associated in such cases, it is premature to assume any significance for PP10 as a tumour marker in clinical practice, because changes in serum hCG levels are much more informative.

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.

Serum concentration of placental proteins in non-pregnant and pregnant subjects

Chorionic gonadotrophin (hCG) and Schwangerschaftsprotein 1 (SP1) were measured in 35 menstrual cycles in 20 women. During the follicular phase, 3 samples were positive for hCG and two of these were also positive for SP1. All these positives occurred on the day of ovulation or immediately before. In the luteal phase 25 specimens showed both hCG and SP1 and two showed only SP1, the positive results occurring 3-15 days after ovulation. The placental proteins were also measured in a further eight women who became pregnant. The pattern in these was quite different. The first positives were detected 8 days after ovulation and by 12 days all the subjects were positive for both proteins. Thereafter both proteins increased sharply in concentration. A group of 139 subjects who, on biological grounds, could not have conceived, showed no positive results.

Pregnancy-associated plasma protein A: a clinically significant predictor of early recurrence in stage II breast carcinoma

The primary tumors and metastases from 30 patients with stage II breast carcinoma treated with low- or standard-dose combination chemotherapy (cyclophosphamide, methotrexate, 5-fluorouracil) were studied by the immunoperoxidase technique for pregnancy-associated plasma protein A (PAPP-A), pregnancy-specific beta-1-glycoprotein (SP-1), and placental protein five (PP-5). In addition to immunostaining, 25 traditional clinicopathologic features were assessed with respect to early (at less than two years) recurrence. Of the 11 patients with early recurrences, nine (82 per cent) were PAPP-A-positive, while 16 of the 19 patients without early recurrences (84 per cent) were PAPP-A-negative (P less than 0.0005). None of the other clinicopathologic features correlated with early recurrence. Immunostaining for PAPP-A is thus a clinically significant predictor of early recurrence in patients with stage II breast carcinoma.

Pregnancy-specific beta-1 glycoprotein (SP-1) in breast carcinoma. Pathologic and clinical considerations

Ectopic production of placental proteins by a variety of nontrophoblastic epithelial tumors is well recognized. Pregnancy-specific beta-1 glycoprotein (SP-1), a recently described placental protein, has been detected both in the serum and tumors of patients with breast carcinoma. To assess the significance of SP-1 in breast carcinoma, we stained 139 cases of primary breast carcinoma for SP-1 using the immunoperoxidase technique. Overall, 55 (40%) of breast cancers were positive for SP-1; focal positivity was also noted in normal breast epithelium and fibrocystic disease. Both intraductal (32%) and infiltrating duct (43%) carcinomas were more often positive than either in situ (5%) or infiltrating (26%) lobular carcinomas. SP-1 positivity in tumors of infiltrating duct morphology less than 3 cm in diameter, correlated highly (P less than 0.01) with the presence of axillary lymph node metastases. The presence of SP-1 in normal breast epithelium and fibrocystic disease and the low rate of positivity in lobular carcinoma casts doubt on the usefulness of SP-1 as a tumor marker. However, these findings suggest that immunopositivity for SP-1 in small infiltrating duct carcinomas may be an indicator of poor prognosis.

Placental protein 12 (PP12) is induced in the endometrium by progesterone

The occurrence of PP12 was studied by the biotin-avidin immunoperoxidase method in the endometrium of 106 premenopausal and postmenopausal women at various phases of the menstrual cycle or during estrogen and progestogen replacement therapy. No PP12 was found in the endometrium under the following conditions: (1) during the proliferative phase, (2) in cystic glandular hyperplasia, (3) during the first 3 postovulatory days in ovulatory cycles, (4) in atrophic postmenopausal endometrium, and (5) in estrogen-stimulated postmenopausal endometrium. PP12 was found in the endometrium under the following conditions: (1) in the secretory endometrium from the fourth postovulatory day onward, (2) in the endometrium during progestogen treatment of previously anovulatory premenopausal women, and (3) in the endometrium from postmenopausal women treated with estrogen followed by combined estrogen and progestogen replacement therapy. These results suggest that PP12 is a P-dependent protein which, in natural cycles, appears in the endometrium around the time of implantation and, in postmenopausal women, can be induced by progestogens after estrogen priming.

Pregnancy-specific beta 1-glycoprotein (SP1) in serum and tissue from patients with benign and malignant breast tumours

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Immunologic and biological properties and clinical significance of placental proteins PP5 and PP12

Among the number of newly isolated placental proteins, PP5 and PP12 share some common characteristics: Both are present in the syncytiotrophoblast of normal placenta and hydatidiform mole, but less frequently, if at all, in choriocarcinoma. The levels in heparinized plasma of both proteins are lower than those in serum, and both are heat-labile. The function of PP12 is completely unknown, whereas PP5 appears to be related to the blood coagulation and fibrinolytic systems at the placental site through its antiplasmin activity. Many exciting avenues of research have been opened to uncover the biological role of these proteins in fetal development and cancer. We are pursuing this research with the immediate goal of assessing the role of PP12 in the blood coagulation system and of studying the expression of both proteins in various forms of cancer.

Serum levels of placental protein 10 (PP10) in women with breast cancer and genital carcinoma and in healthy male and female subjects

PP10, a recently characterized glycoprotein from human placenta, was studied using a specific double-antibody radioimmunoassay in the serum of about 100 volunteers and 200 cancer patients. Elevated levels (greater than 20 nU/ml) were found in 87% of patients with primary breast cancer, in 100% of those with primary genital tumours and in 78% of patients with recurrent disease. PP10 was also measured in tumour extracts and in some patients with benign tumours. The serum concentration decreased within a few weeks after removal of the tumour. There were no significant correlations of the PP10 level with age, tumour size, histological grading or lymph node involvement. Sequential determinations of PP10 during cytostatic therapy sometimes showed rising levels accompany the development of metastases. PP10 can be regarded as a tumour associated protein and a tumour marker in gynaecological practice.

Concentration of placental protein 10 (PP10) in maternal serum and amniotic fluid throughout normal gestation and in pregnancy complicated by fetal growth retardation

PP10, a new placental glycoprotein, was studied by a specific and sensitive double-antibody radioimmunoassay in maternal serum and other body fluids throughout pregnancy. The mean value of serum PP10 in healthy nonpregnant individuals was approximately 10 microU/l. During normal pregnancy it rose to 3,500 microU/l. The rate of rise was obtained from 78 normal pregnancies with 279 single assay values from weeks 6-40. The shape of the curve resembled that for other placental proteins (HPL, SP1). PP10 levels in amniotic fluid were measured in 145 samples from weeks 13-55 of normal pregnancies and at term. The mean concentration was 500 microU/l until week 18 and then rose slowly. Cord blood contained only trace amounts. PP10 was not found in maternal urine. The concentration in maternal serum and amniotic fluid was higher in twin pregnancies than in singleton pregnancies. In 46 cases with low birth weights the PP10 levels in maternal serum were significantly lower than normal. Simultaneous measurements of PP10 and E3, HPL and SP1 were made in 17 individual follow-up's. PP10 was comparable with E3 and appeared to be better than HPL and SP1 in predicting intrauterine fetal growth retardation.

Radioimmunoassay of placental protein 12: levels in amniotic fluid, cord blood, and serum of healthy adults, pregnant women, and patients with trophoblastic disease

A radioimmunoassay for placental protein 12 (PP12) is described and the levels in amniotic fluid, cord blood, and serum of nonpregnant individuals, pregnant women, and patients with trophoblastic disease are presented. During pregnancy, the highest PP12 levels were found at 22 to 23 weeks (mean +/- SD, 169 +/- 123 ng/ml), and there was a transient decline at 32 to 33 weeks (63 +/- 23 ng/ml). In amniotic fluid, the levels were 100 to 1,000 times higher than in maternal serum. In cord blood at birth, the values were of the same magnitude as in maternal serum. Also healthy nonpregnant women and men had PP12-like immunoreactivity in serum. Nonpregnant women (9 to 47 ng/ml) had higher levels than men (undetectable to 21 ng/ml). Elevated levels up to 84 ng/ml were occasionally observed in trophoblastic disease, both hydatidiform mole and choriocarcinoma, but they bore no correlation with the human chorionic gonadotropin levels. On the basis of these results PP12 is not a suitable marker for trophoblastic disease. PP12 values in normal pregnancy provide the basis for the evaluation of PP12 levels in abnormal pregnancy.

Ectopic production of placenta-"specific" tissue proteins (PP5 and PP11) by malignant breast tumors

With use of an enzyme-bridge immunoperoxidase (PAP) technique, an immunohistochemical localization of the two new placenta-"specific" tissue proteins, PP5 and PP11, was investigated in 16 cases of breast cancer. PP5 was localized in the cytoplasm of breast cancer cells in 62.5% of cases examined and PP11, in 46.7%. Thus PP5 and PP11 may be markers for breast cancer and the detection of these proteins in sera from breast cancer patients may be more reliable and useful in the detection and monitoring of breast cancer patients than the determination of SP1, PP10, or PP12, other pregnancy "specific" proteins.

Immunohistochemical location of placental proteins (PP8, 9, 10, 11, 12) in human term placentae

By using an immunoglobulin enzyme bridge (PAP) technique, the location of two ubiquitous tissue proteins (PP8, PP9) and three placental specific tissue proteins (PP10, PP11, PP12) was investigated in ethanol/acetic acid-fixed paraffin-embedded human term placentae. PP8 was found mainly in both the cytoplasm and the nucleus of trophoblast cells (chorion) and syncytiotrophoblast (villi). PP9 was found in the cytoplasm of trophoblast cells (chorion), the fibrous part of interstitial connective tissues (villi), and the cytoplasm of histiocytes (villi, amnion, and decidua). PP10 was found in the cytoplasm of epithelium (amnion) and in both the cytoplasm and the nucleus of syncytiotrophoblast (villi). PP12 was found in the cytoplasm of histiocytes in decidua, amnion, and chorion and the cytoplasm of syncytiotrophoblast (villi). In addition, stains for PP8, PP10, and PP12 were taken up by the cytoplasm of histiocytes found in amnion, villi, the intervillous space, and decidua, in contrast to PP11, which was found to be specific to the cytoplasm of trophoblast cells (chorion and villi). Possible clinical applications of these findings are discussed.