Differentially regulated production of platelet-derived growth factor and of transforming growth factor beta by a human teratocarcinoma cell line

Comparison of the prognostic value of immunoinflammation-based biomarkers in patients with gastric cancer

Background: Systemic immune-inflammation index (SII)—comprising platelet, neutrophil, and lymphocyte count—is an objective and reliable biomarker for predicting the prognosis in cancer patients because it comprehensively reflects the balance between host inflammatory and immune responses. In this study, we clarified the prognostic impact of immunoinflammation-based indices, i. e. SII, neutrophil/lymphocyte ratio (NLR), and platelet/lymphocyte ratio (PLR), in gastric cancer patients.

Results: In multivariate analysis, the American Society of Anesthesiologists physical status (ASA-PS) (hazard ratio [HR]: 3.366, p < 0.001), tumor differentiation (HR: 1.705, p = 0.020), pathological Tumor, Node, Metastasis (pTNM) stage (HR: 2.160, p = 0.008), and carcinoembryonic antigen (CEA) (HR: 1.964, p = 0.003) were independent prognostic factors for OS in all patients. Further, multivariate analysis revealed that age (HR: 2.088, p = 0.040), ASA-PS (HR: 2.339, p = 0.043), tumor differentiation (HR: 1.748, p = 0.044), and pTNM stage (HR: 2.114, p = 0.024) were independent prognostic factors for OS among patients without inflammation; SII was not a prognostic factor for OS. Meanwhile, body mass index (HR: 5.055, p = 0.011), ASA-PS (HR: 3.403, p = 0.007), and SII (HR: 4.208, p = 0.026) were independent prognostic factors for OS among patients with inflammation.

Materials and Methods: We performed a retrospective review of 412 patients who underwent curative laparoscopic gastrectomy. The prognostic value of SII was compared between a low SII group (SII<661.9) and high SII group (SII≥661.9). We analyzed the predictive ability of immunoinflammation-based indices for overall survival (OS) based on a C-reactive protein (CRP) level of 0.5.

Conclusions: Compared to NLR and PLR, SII is the most significant prognostic biomarker for OS, especially in gastric cancer patients with inflammation.

Cancer Immune Equilibrium and Schizophrenia Have Similar Interferon-γ, Tumor Necrosis Factor-α, and Interleukin Expression: A Tumor Model of Schizophrenia

For at least a century, a debate has continued as to whether cancer risk is reduced in schizophrenia. Genetic studies have also suggested the 2 conditions may share protein transcriptional pathways. The author predicted that if the pathophysiology of schizophrenia confers protection from cancer, then the immunology of schizophrenia should reflect a state of tumor suppression, ie, the opposite of tumor escape. To examine this possibility, the author performed a literature search for measurements of cytokines in drug-naïve first episode subjects with schizophrenia for comparison with cytokine expression in tumor escape vs tumor suppression. The comparison showed that instead of either tumor suppression or escape, schizophrenia appears to be in a state of tumor equilibrium. Based on this finding, the author hypothesized that the clinical presentation of schizophrenia may involve cell transformation similar to an early stage of cancer initiation or an attenuated tumorigenesis. While this condition could reflect the presence of an actual tumor such as an ovarian teratoma causing anti-NMDA receptor encephalitis, it would only explain a small percentage of cases. To find a more likely tumor model, the author then compared the cytokine profile of schizophrenia to individual cancers and found the best match was melanoma. To demonstrate the viability of the theory, the author compared the hallmarks, emerging hallmarks, and enabling characteristics of melanoma to schizophrenia and found that many findings in schizophrenia are understood if schizophrenia is a condition of attenuated tumorigenesis.

Vitamin-regulated cytokines and growth factors in the CNS and elsewhere

There is a growing awareness that natural vitamins (with the only exception of pantothenic acid) positively or negatively modulate the synthesis of some cytokines and growth factors in the CNS, and various mammalian cells and organs. As natural vitamins are micronutrients in the human diet, studying their effects can be considered a part of nutritional genomics or nutrigenomics. A given vitamin selectively modifies the synthesis of only a few cytokines and/or growth factors, although the same cytokine and/or growth factor may be regulated by more than one vitamin. These effects seem to be independent of the effects of vitamins as coenzymes and/or reducing agents, and seem to occur mainly at genomic and/or epigenetic level, and/or by modulating NF-kappaB activity. Although most of the studies reviewed here have been based on cultured cell lines, but their findings have been confirmed by some key in vivo studies. The CNS seems to be particularly involved and is severely affected by most avitaminoses, especially in the case of vitamin B(12). However, the vitamin-induced changes in cytokine and growth factor synthesis may initiate a cascade of events that can affect the function, differentiation, and morphology of the cells and/or structures not only in the CNS, but also elsewhere because most natural vitamins, cytokines, and growth factors cross the blood-brain barrier. As cytokines are essential to CNS-immune and CNS-hormone system communications, natural vitamins also interact with these circuits. Further studies of such vitamin-mediated effects could lead to vitamins being used for the treatment of diseases which, although not true avitaminoses, involve an imbalance in cytokine and/or growth factor synthesis.

Positive effect of transplantation of hNT neurons (NTera 2/D1 cell-line) in a model of familial amyotrophic lateral sclerosis

Transplantation of hNT Neurons derived from the human teratocarcinoma cell-line (NTera2/D1) has been shown to ameliorate motor dysfunction in a number of injury or disease models in which the deficits are fairly localized. However, these cells have not been used before in a model with more extensive neurodegeneration. The aim of this study is to determine the effects of hNT Neuron transplants on motor neuron function in a mouse model of familial amyotrophic lateral sclerosis (FALS) in which there is a substitution of Alanine for Glycine at position 93 of the human SOD1 gene (G93A). Amyotrophic lateral sclerosis is a fatal degenerative motor neuron disease affecting the spinal cord, brainstem, and cortex. This disease clinically manifests as progressive muscular weakness and atrophy, leading to paralysis and death within 3-5 years of diagnosis. The FALS represents 10-13% of all cases. A range of behavioral tests was used to examine spontaneous locomotor activity, coordination, and muscle strength of mice. Long-term (10-11 weeks) transplantation of hNT Neurons into the L(4)-L(5) segments of the ventral horn spinal cord of FALS(G93A) mice at 7 weeks of age (before onset of overt behavioral symptoms of disease) delayed the onset of motor dysfunction for at least 3 weeks. The average lifespan of the transplanted mice was 128 days compared to 106 days for media-injected group. The last mouse in the hNT Neuron transplanted group was euthanized at 135 days of age when it display partial paralysis of the hindlimbs. Immunohistochemical analysis of the implanted spinal cords demonstrated the survival of grafted hNT Neurons and showed many healthy-appearing motor neurons near the implant site. These results suggest that hNT Neuron transplantation may be a promising therapeutic strategy for ALS.

Novel cellular approaches to repair of neurodegenerative disease: from Sertoli cells to umbilical cord blood stem cells

Neural transplantation is a promising approach to the treatment of neurodegenerative diseases and brain injury that has been shown to be efficacious in many animal models. However, the use of fetal tissue limits the acceptability and widespread application of this technique. In this review we discuss possible alternative cell sources that may be used to repair the brain and spinal cord, with a focus on Sertoli cells, hNT Neurons, bone marrow and umbilical cord blood derived stem cells.

Novel BTB/POZ domain zinc-finger protein, LRF, is a potential target of the LAZ-3/BCL-6 oncogene

BTB/POZ-domain C2H2 zinc(Zn)-finger proteins are encoded by a subfamily of genes related to the Drosophila gap gene krüppel. To date, two such proteins, PLZF and LAZ-3/BCL-6, have been implicated in oncogenesis. We have now identified a new member of this gene subfamily which encodes a 62 kDa Zn-finger protein, termed LRF, with a BTB/POZ domain highly similar to that of PLZF. Both human and mouse LRF genes, which localized to syntenic chromosomal regions (19p13.3 and 10B5.3, respectively), were widely expressed in adult tissues and cell lines. At approximately 9.5-10.0 days of embryonic development, the mouse LRF gene was expressed in the limb buds, pharyngeal arches, tail bud, placenta and neural tube. The LRF protein associated in vivo with LAZ-3/BCL-6, but not with PLZF to which it was more related. Although the LRF, or LAZ-3/BCL-6, BTB/POZ domain could readily homodimerize, no heterodimerization was detected in vivo between the LRF and LAZ-3/BCL-6 BTB/POZ domains and interaction between full length LRF and LAZ-3/BCL-6 required the presence of both the BTB/POZ domain and Zn-fingers in each partner protein. As expected from the above results, LRF and LAZ-3/BCL-6 also colocalized with each other in the nucleus. Taken together, our findings suggest that BTB/ POZ-domain Zn-finger proteins may function as homo and heterodimeric complexes whose formation, and hence the resultant effect on transcription of their downstream target genes, is determined by the levels and expression domains of a given partner protein.

Oct-4 regulates alternative platelet-derived growth factor alpha receptor gene promoter in human embryonal carcinoma cells

Expression of the platelet-derived growth factor alpha-receptor (PDGFalphaR) gene is tightly controlled in mammalian embryogenesis. A well established model system to study human embryogenesis is the embryonal carcinoma cell line Tera2. We have shown previously that retinoic acid-differentiated Tera2 cells express two PDGFalphaR transcripts of 6.4 kilobase pairs (kb) (encoding the full-length receptor) and 3.0 kb, respectively, whereas in contrast, undifferentiated Tera2 cells express PDFGalphaR transcripts of 1.5 kb and 5.0 kb. Here we show that this switch in PDGFalphaR expression pattern during differentiation of Tera2 cells results from alternative promoter use. In undifferentiated cells, a second promoter is used, which is located in intron 12 of the PDGFalphaR gene. Functional analysis shows that this promoter contains a consensus octamer motif, which can be bound by the POU domain transcription factor Oct-4. Oct-4 is expressed in undifferentiated Tera2 cells but not in retinoic acid-induced differentiated cells. Mutation of the octamer motif decreases promoter activity, while ectopic expression of Oct-4 in differentiated Tera2 cells specifically enhances the activity of this PDGFalphaR promoter. Therefore, we suggest that an important aspect in the maintenance of the undifferentiated state of human embryonal carcinoma cells results from Oct-4 expression, which thereupon activates this PDGFalphaR promoter.

Signals controlling the expression of PDGF

PDGF is an important polypeptide growth factor that plays an essential role during early vertebrate development and is associated with tissue repair and wound healing in the adult vertebrate. Moreover, PDGF is thought to play a role in a variety of pathological phenomena, such as cancer, fibrosis and atherosclerosis. PDGF is expressed as a dimer of A and/or B chains, the precursors of which are encoded by two single copy genes. Although the PDGF genes are expressed coordinately in a number of cell types, they are independently expressed in a majority of cell types. The expression of either PDGF gene can be affected by very diverse extracellular stimuli and the type of response is dependent on the cell type that is exposed to the stimulus. Expression of the PDGF chains can be modulated at every imaginable level: by regulating accessibility of the transcription start site, by varying the transcription initiation rate, by using alternative transcription start sites, by alternative splicing, by using alternative polyadenylation signals, by varying mRNA decay rates, by regulating efficiency of translation, by protein modification, and by regulating secretion. Even upon secretion, the activity of PDGF can be modulated by non-specific or specific PDGF-binding proteins. This review provides an overview of the cell types in which the PDGF genes are expressed, of the factors that are known to affect the expression of PDGF, and of the various levels at which the expression of PDGF genes can be regulated.

Identification of the type-B receptor for platelet-derived growth factor in human embryonal carcinoma cells

The human embryonal carcinoma (EC) cell line Tera 2 clone 13 (T2/13) can be induced to differentiate in vitro into neuroectodermal cell types with retinoic acid. Undifferentiated cells are characterized by rapid proliferation, whereas differentiated cells show a prolonged generation time, have a limited life span, and possess new cell-surface markers. In the present study we establish that both differentiated and undifferentiated T2/13 cells express the type-B platelet-derived growth factor (PDGF) receptor mRNA and bind PDGF-BB with high affinity. Differentiation causes a three-fold increase in receptor number per cell and leaves the affinity of the receptors unaffected. These data are the first to describe expression of this receptor in EC cells. The biosynthesis and degradation of this receptor were studied in undifferentiated as well as in differentiated T2/13 cells using an anti-type-B receptor antibody. These experiments revealed that high concentrations of recombinant PDGF-AA did not accelerate receptor metabolism in both cell types. In contrast, human PDGF or recombinant PDGF-BB added to the culture dishes readily increased receptor degradation. These results demonstrate that T2/13 cells express functional type-B PDGF receptors and suggest that cells responsive to PDGF might be present during mammalian development before the onset of mesoderm formation.

Expression and developmental regulation of the k-FGF oncogene in human and murine embryonal carcinoma cells

Embryonal carcinoma (EC) cells provide an effective model system for studying growth factor production and regulation during mammalian embryogenesis. Our earlier data indicated that the mouse EC cell lines F9 and PC-13 and the human EC cell line NT2/D1 produce a factor with properties similar to those ascribed to members of the fibroblast growth factor (FGF) family and that production of this FGF-related factor is suppressed when all three EC cell lines are induced to differentiate. Subsequent studies suggested that NT2/D1 EC cells express transcripts for basic FGF (bFGF). The current study confirms and extends these findings using a combination of reverse transcription and polymerase chain reaction (RT-PCR). In this study, the expression of bFGF and other members of the FGF family have been examined in F9 and PC-13 cells in addition to NT2/D1 EC cells. In contrast to NT2/D1 EC cells, bFGF expression could not be detected in F9 and PC-13 EC cells. Additionally, expression of four other members of the FGF family (acidic FGF, int-2, FGF-5, and FGF-6) were not detected in NT2/D1, F9, or PC-13 EC cells. However, expression of another member of the FGF family, the k-FGF oncogene, was detected in NT2/D1, F9, and PC-13 EC cells. Moreover, the expression of this transcript is reduced dramatically when each of the three EC cell lines is induced to differentiate. Taken together, our findings argue that expression of the k-FGF oncogene is predominantly responsible for the FGF-related activity detected in EC cells and that differentiation of these EC cells results in suppression of this oncogene.

Isolation and characterization of a multipotent clone of human embryonal carcinoma cells

Histopathological studies suggest that the stem cells of human teratomas may be classified into two major categories: nullipotent stem cells, and multipotent stem cells, capable both of self-renewal and differentiation into a wide range of somatic and extraembryonic cell types. We have isolated a multipotent stem cell clone from the human teratoma cell line GCT 27, and compared its properties to a nullipotent clone derived from the same strain. The multipotent clone GCT 27 X-1 gave rise to colonies of mixed cell morphology in vitro. Analysis of cell surface, cytostructural and extracellular matrix markers in GCT 27 X-1 cells showed that the stem cells of this line were very similar in phenotype to nullipotent cells. The two cell clones were predominantly hypotriploid, and contained several marker chromosomes in common. GCT 27 X-1 was feeder-cell-dependent for continuous growth in vitro; removal of the feeder layer resulted in differentiation of the stem cells into a variety of cell types, some with characteristics of extraembryonic endoderm, others showing neuronal properties. When transplanted into nude mice, GCT 27 X-1 cells gave rise to teratocarcinomas containing embryonal carcinoma stem cells, and many other cell types: yolk sac carcinoma cells; cells producing alphafetoprotein or human chorionic gonadotrophin; glandular, columnar, cuboidal, and squamous epithelium; primitive mesenchyme and cartilage; neuroectodermal cells. Nullipotent GCT 27 C-1 cells could form colonies in the absence of feeder layers, but multipotent GCT 27 X-1 cells could not. While a range of known growth factors and related substances failed to substitute for feeder layers in supporting the growth of GCT 27 X-1 stem cells, supernatants from yolk sac carcinoma cell line GCT 44 could partially replace the feeder cell requirement. Thus, the results revealed a basic difference in growth control between these multipotent and nullipotent human embryonal carcinoma cells, and suggested a possible paracrine regulatory pathway between multipotent stem cells and yolk sac carcinoma cells.

Transforming growth factor-beta and its receptor are differentially regulated in human embryonal carcinoma cells

The human embryonal carcinoma cell lines Tera-2 clone 13 and NTera-2 clone D1 can be induced by retinoic acid to differentiate in vitro into neuroectodermal derivatives. The undifferentiated cells are rapidly proliferating and tumorigenic, whereas retinoic-acid-treated cells possess a decreased growth rate, lose their transformed phenotype and show a finite lifespan. Differentiation is accompanied by a marked increase in the levels of mRNA for TGF-beta 1 and TGF-beta 2 and the production of TGF-beta activity. Just like murine embryonal carcinoma cells the growth of Tera-2 clone 13 cells is not affected by the addition of either TGF-beta 1 or TGF-beta 2 to the culture medium. In contrast to published data on murine embryonal carcinoma cells, Tera-2 clone 13 and NTera-2 clone D1 cells bind TGF-beta 1 with high affinity, which is due to the presence of type-III TGF-beta receptors. Furthermore, and again in contrast to murine embryonal carcinoma cells, treatment of the human embryonal carcinoma cells with retinoic acid causes a nearly complete loss of TGF-beta 1 binding sites. These results are discussed in the light of similarities and differences in the regulation of growth and differentiation of human and murine embryonal carcinoma cell lines.