Germ Cell Expression of an Isolated Human Endogenous Retroviral Long Terminal Repeat of the HERV-K/HTDV Family in Transgenic Mice

ABSTRACT In contrast to most other human endogenous retroviral families, various HERV-K members have open reading frames that code for functional viral proteins which can form noninfectious particles in some germ cell tumors. The HERV-K viral genes are highly transcribed in germ cell tumors but are transcribed to lower or undetectable levels in most other tissue and tumor types. To further analyze the expression patterns of these proviruses, long terminal repeats (LTRs) were isolated from the human genome and used in reporter gene assays. Expression of some HERV-K LTRs was found to be high in human and murine germ cell tumors (testicular teratocarcinomas) and low in non-germ-cell tumors. Furthermore, upon differentiation of a teratocarcinoma cell line, the expression of an active LTR dropped dramatically, suggesting developmental regulation of these proviral LTRs. Transgenic mice harboring an active LTR driving lacZ expression were generated and analyzed. Adult mouse testes showed the highest levels of expression, and the transgene staining appeared to be restricted primarily to the more undifferentiated spermatocytes. Most other tissues analyzed revealed very low or undetectable levels of expression both by reverse transcription-PCR and by Northern blot analysis. Whether the restricted expression of HERV-K in germ cells and in germ cell-derived tumors is of significant importance during development or tumorigenesis remains to be elucidated. Germ line expression of these viruses would allow for their expansion and movement, while somatic repression would ensure limited insertional mutagenesis and misexpression in an individual.

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Prognostic Value of Apoptosis-Inducing Factor (AIF) in Germ Cell Tumors

Cancers ◽

10.3390/cancers13040776 ◽

2021 ◽

Vol 13 (4) ◽

pp. 776

Author(s):

Katarina Letkovska ◽

Pavel Babal ◽

Zuzana Cierna ◽

Silvia Schmidtova ◽

Veronika Liskova ◽

...

Keyword(s):

Germ Cell ◽

Nuclear Translocation ◽

Malignant Tumors ◽

Expression Patterns ◽

Germ Cell Tumors ◽

Testicular Tissue ◽

Testicular Germ Cell ◽

Visceral Metastases ◽

Apoptosis Inducing Factor ◽

Clinicopathological Variables

Apoptosis is a strictly regulated process essential for preservation of tissue homeostasis. This study aimed to evaluate expression of apoptosis inducing factor (AIF) in testicular germ cell tumors (GCTs) and to correlate expression patterns with clinicopathological variables. Formalin-fixed and paraffin-embedded specimens of non-neoplastic testicular tissue and GCTs obtained from 216 patients were included in the study. AIF expression was detected by immunohistochemistry, scored by the multiplicative quickscore method (QS). Normal testicular tissue exhibits higher cytoplasmic granular expression of AIF compared to GCTs (mean QS = 12.77 vs. 4.80, p < 0.0001). Among invasive GCTs, mean QS was the highest in embryonal carcinoma, yolk sac tumor and seminoma, lower in teratoma and the lowest in choriocarcinoma. No nuclear translocation of AIF was observed. Nonpulmonary visceral metastases were associated with lower AIF expression. Metastatic GCTs patients with high AIF expression had better overall survival compared to patients with low AIF expression (HR = 0.26, 95% CI 0.11–0.62, p = 0.048). We observed significantly lower AIF expression in GCTs compared to normal testicular tissue, which is an uncommon finding in malignant tumors. AIF downregulation might represent one of the mechanisms of inhibition of apoptosis and promotion of cell survival in GCTs.

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EXPRESSION PATTERNS OF CANCER TESTIS ANTIGENS IN TESTICULAR GERM CELL TUMORS AND ADJACENT TESTICULAR TISSUE

The Journal of Urology ◽

10.1097/00005392-200105000-00102 ◽

2001 ◽

pp. 1790-1794 ◽

Cited By ~ 1

Author(s):

TAKESHI YUASA ◽

KEISEI OKAMOTO ◽

TAKAHIRO KAWAKAMI ◽

MUTSUKI MISHINA ◽

OSAMU OGAWA ◽

...

Keyword(s):

Germ Cell ◽

Expression Patterns ◽

Germ Cell Tumors ◽

Testicular Tissue ◽

Testicular Germ Cell Tumors ◽

Testicular Germ Cell ◽

Cancer Testis Antigens ◽

Cancer Testis

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EXPRESSION PATTERNS OF CANCER TESTIS ANTIGENS IN TESTICULAR GERM CELL TUMORS AND ADJACENT TESTICULAR TISSUE

The Journal of Urology ◽

10.1016/s0022-5347(05)66415-4 ◽

2001 ◽

Vol 165 (5) ◽

pp. 1790-1794 ◽

Cited By ~ 24

Author(s):

TAKESHI YUASA ◽

KEISEI OKAMOTO ◽

TAKAHIRO KAWAKAMI ◽

MUTSUKI MISHINA ◽

OSAMU OGAWA ◽

...

Keyword(s):

Germ Cell ◽

Expression Patterns ◽

Germ Cell Tumors ◽

Testicular Tissue ◽

Testicular Germ Cell Tumors ◽

Testicular Germ Cell ◽

Cancer Testis Antigens ◽

Cancer Testis

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Germ line and embryonic expression of Fex, a member of the Drosophila F-element retrotransposon family, is mediated by an internal cis-regulatory control region.

Molecular and Cellular Biology ◽

10.1128/mcb.16.6.2998 ◽

1996 ◽

Vol 16 (6) ◽

pp. 2998-3007 ◽

Cited By ~ 9

Author(s):

B Kerber ◽

S Fellert ◽

H Taubert ◽

M Hoch

Keyword(s):

Germ Line ◽

Expression Patterns ◽

Regulatory Region ◽

Open Reading Frames ◽

Regulatory Control ◽

Nucleic Acid Binding ◽

Coding Region ◽

Reading Frame ◽

Cis Acting ◽

Retrotransposon Family

The F elements of Drosophila melanogaster belong to the superfamily of long interspersed nucleotide element retrotransposons. To date, F-element transcription has not been detected in flies. Here we describe the isolation of a member of the F-element family, termed Fex, which is transcribed in specific cells of the female and male germ lines and in various tissues during embryogenesis of D. melanogaster. Sequence analysis revealed that this element contains two complete open reading frames coding for a putative nucleic acid-binding protein and a putative reverse transcriptase. Functional analysis of the 5' region, using germ line transformation of Fex-lacZ reporter gene constructs, demonstrates that major aspects of tissue-specific Fex expression are controlled by internal cis-acting elements that lie in the putative coding region of open reading frame 1. These sequences mediate dynamic gene expression in eight expression domains during embryonic and germ line development. The capacity of the cis-regulatory region of the Fex element to mediate such complex expression patterns is unique among members of the long interspersed nucleotide element superfamily of retrotransposons and is reminiscent of regulatory regions of developmental control genes.

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Differential expression of DNA methyltransferases and demethylases among the various testicular germ cell tumor subtypes

Epigenomics ◽

10.2217/epi-2020-0066 ◽

2020 ◽

Vol 12 (18) ◽

pp. 1579-1592 ◽

Cited By ~ 1

Author(s):

João Lobo ◽

Rita Guimarães ◽

Vera Miranda-Gonçalves ◽

Sara Monteiro-Reis ◽

Mariana Cantante ◽

...

Keyword(s):

Germ Cell ◽

Cell Lines ◽

De Novo ◽

Quantitative Polymerase Chain Reaction ◽

Expression Patterns ◽

Germ Cell Tumors ◽

In Silico Analysis ◽

Dna Methyltransferases ◽

Differentially Expressed ◽

Testicular Germ Cell

Aim: Characterize DNA methyltransferases/demethylases expression in testicular germ cell tumors (TGCTs). Methods: In silico analysis of TCGA database, assessment of transcript levels of most relevant enzymes in four TGCT cell lines and validation in patient cohort (real-time quantitative polymerase chain reaction; immunohistochemistry). Results: DNMT3A, DNMT3B and TET2 were the most differentially expressed between seminomas (SEs) and nonseminomas (NSs). DNMT3B was significantly overexpressed in NS-related cell lines, and the opposite was found for TET2. Significantly higher DNMT3A/B mRNA expression was observed in NS, indicating a role for de novo methylation in reprogramming. Significantly higher TET2 protein expression was observed in SEs, suggesting active demethylation contributes for SE hypomethylated state. More differentiated histologies disclosed distinct expression patterns. Conclusion: DNA-modifying enzymes are differentially expressed between TGCT subtypes, influencing reprogramming and differentiation.

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Human growth-differentiation factor 3 (hGDF3): developmental regulation in human teratocarcinoma cell lines and expression in primary testicular germ cell tumours

Oncogene ◽

10.1038/sj.onc.1201515 ◽

1998 ◽

Vol 16 (1) ◽

pp. 95-103 ◽

Cited By ~ 38

Author(s):

Andrea AD Caricasole ◽

Ron HN van Schaik ◽

Laura M Zeinstra ◽

Cristel DJ Wierikx ◽

Ruud JHLM van Gurp ◽

...

Keyword(s):

Germ Cell ◽

Cell Lines ◽

Developmental Regulation ◽

Human Growth ◽

Germ Cell Tumours ◽

Testicular Germ Cell ◽

Teratocarcinoma Cell ◽

Testicular Germ Cell Tumours ◽

Differentiation Factor

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GCT-72. ANALYSIS OF microRNA EXPRESSION PROFILE OF INTRACRANIAL GERM CELL TUMORS: A PROMISING TOOL FOR DIFFERENTIAL DIAGNOSIS

Neuro-Oncology ◽

10.1093/neuonc/noaa222.288 ◽

2020 ◽

Vol 22 (Supplement_3) ◽

pp. iii342-iii343

Author(s):

Yoshiko Nakano ◽

Kaishi Satomi ◽

Hirokazu Takami ◽

Ryo Nishikawa ◽

Fumiyuki Yamasaki ◽

...

Keyword(s):

Germ Cell ◽

Expression Profile ◽

Mirna Expression ◽

Expression Patterns ◽

Germ Cell Tumors ◽

Tumor Tissues ◽

Intracranial Germ Cell Tumors ◽

And Control ◽

Pediatric Brain ◽

Control Samples

Abstract INTRODUCTION One of the major limitations of pathological diagnosis for intracranial germ cell tumors (iGCTs) is tumor heterogeneity, which cannot be evaluated using limited amount of tumor tissues. In this study, we performed comprehensive analysis of microRNA (miRNA) of iGCTs to identify miRNAs profile to help determine tumor diagnosis. METHODS RNA was extracted from frozen samples of 16 germinoma and 14 NGGCTs. Five non-iGCT pediatric brain tumor tissues were used as control. miRNA expression analysis was performed using a 3D-Gene Human miRNA Oligo Chip ver.22 (Toray Industries, Inc) which was designed to detect 2565 miRNAs. The miRNA expression profile was analyzed using t-SNE dimensionality reduction and weighted average difference method (WAD). RESULTS Different histological subtypes of the iGCTs and control samples were clustered into distinct classes. Furthermore, we found that the germinoma, NGGCTs and control samples may be readily distinguished by expression patterns of miR-200 and miR-371a-3p: a high expression of miR-200 was observed in the NGGCTs, whereas a high expression of miR-371a-3p was observed in all cases of germinoma and some of NGGCTs. Neither of miR-200 nor miR371-3p was highly expressed in control samples. CONCLUSION Our data indicated that germ cell tumor and other pediatric brain tumors, and also germinoma and NGGCT can be distinguished by expression patterns of 2 micro RNA, miR-200 and miR-371a-3p. These 2 microRNA may serve as a useful tool for supporting the pathological diagnosis of iGCTs.

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The impact of circulating free tumor DNA (cfDNA) in testicular germ cell tumors (TGCT) management.

Journal of Clinical Oncology ◽

10.1200/jco.2020.38.15_suppl.e17519 ◽

2020 ◽

Vol 38 (15_suppl) ◽

pp. e17519-e17519

Author(s):

Eugen Kubala ◽

Violeta Bakardjieva-Mihaylova ◽

Karolina Skvarova-Kramarzova ◽

Martina Slamova ◽

Petr Triska ◽

...

Keyword(s):

Germ Cell ◽

Disease Progression ◽

Peripheral Blood ◽

Germ Line ◽

Germ Cell Tumors ◽

Testicular Germ Cell Tumors ◽

Testicular Germ Cell ◽

Primary Tumors ◽

The Impact ◽

Tumor Dna

e17519 Background: The clinical management of testicular germ cell tumors (TGCT) has not changed much for decades; most importantly, novel prognostic factors indicating the need of adjuvant chemotherapy and factors related to the development of cisplatin resistance would be needed. Circulating free tumor DNA (cfDNA) is an easily available and valuable source of genetic material, which may bring clinically relevant information. Methods: After ethical committee approval and patient informed consent, peripheral blood (PB) samples were taken from TGCT patients at the diagnosis (after orchidectomy), after 2 cycles of chemotherapy, at the end of treatment, and at relapse or disease progression, if applicable. Clinical data of all patients were recorded. The PB samples were processed immediately after collection, plasma was separated by centrifugation, cfDNA was extracted by QIAmp Circulating Nucleic Acid kits (Qiagen), its quality and quantity was assessed by capillary electrophoresis (Agilent) and qPCR for a house-keeping gene. Selected samples were subjected to whole exome sequencing using SureSelectXT HS + Human All Exon v6 kits (Agilent) on NextSeq (Illumina) platform, together with the corresponding primary testicular tumor and peripheral blood mononuclears as a germ-line control. Statistical analyses were performed using non-parametric tests. Results: Sixty-three samples of 41 patients have been analyzed. The median amount of detected cfDNA did not significantly differ from non-malignant controls, was similar in seminoma and non-seminoma pts, but was significantly higher (p = 0.01) in pts with disease progression. In pts with elevated cfDNA levels, these decreased after 2 and 4 cycles of chemotherapy. In 5 sequenced pts, molecular aberrations (somatic missense or frameshift mutations) were found in genes CDC27 (2 pts), RBMX (4 pts), TPTE2 (3 pts), and TSPAN16 (1 pt). These aberrations were also detected in primary tumors but with lower frequencies, and were not present in germ-line DNA. CDC27 mutations have been described in TGCT previously. The other genes have not yet been linked to TGCT, although their role in spermatogenesis and cell proliferation is well known. The presence of mitochondrial DNA was not detected in cfDNA. Conclusions: High levels of cfDNA are detectable in pts with disease progression where they reflect the total tumor load; the molecular analysis of cfDNA revealed novel aberrations that may play a role in TGCT development. Supported by grants MH CZ - DRO00064190TN, CDRO00064203FNM and MEYS NPU I LO1604

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Transgenic mice

Genome ◽

10.1139/g89-165 ◽

1989 ◽

Vol 31 (2) ◽

pp. 938-949 ◽

Cited By ~ 31

Author(s):

C. Babinet ◽

D. Morello ◽

J. P. Renard

Keyword(s):

Homologous Recombination ◽

Transgenic Mice ◽

Dna Sequences ◽

Insertional Mutagenesis ◽

Germ Line ◽

Embryonic Stem ◽

Physiological Role ◽

Cis Acting ◽

Endogenous Genes

Stable integration into the mouse genome of exogenous genetic information has become, over the past few years, a very potent approach for different aspects of biology. It is a common feature that the integrated exogenous gene (the transgene) is expressed properly both spatially and temporally. Constructing different lines of transgenic mice carrying various versions of a gene, therefore, permits cis acting DNA sequences involved in the specificity of expression to be defined, in the context of the developing animal. This in turn opens the way to a variety of experiments in which a given gene product is targeted to one or another cell type, thus offering some insight into the physiological role of this product. Such a strategy has been used, for example, to address the questions of the role of oncogenes in malignant transformation. The insertion of foreign DNA per se may disrupt the function of endogenous genes, thus creating an insertional mutation. The corresponding affected genes may subsequently be cloned, using the transgene as a tag. Finally, the ability to perform homologous recombination, recently demonstrated with embryonic stem cells that can colonize the germ line of a foreign embryo, should constitute in the near future a unique way to analyse in detail the functioning of the mammalian genome.Key words: transgenic mice, oncogenes, insertional mutagenesis, cis-acting sequences, homologous recombination.

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