Human Seminoma Research Articles

Influence of different pH milieu on the structure and function of human Aurora kinase B protein (AURK-B): Amalgamation of both spectroscopic and computational approach

Aurora kinase B (AURK-B) is a serine/threonine kinase protein that plays an essential role in chromosomal separation during the cell cycle event. AURK-B is highly expressed in various types of cancer such as human seminoma, thyroid carcinoma, non-small cell lung carcinoma (NSCLC), oral carcinoma, and gastric cancer. Hence, it is a potential therapeutic target in the treatment of various cancers. The structure of AURK-B in complex with one of its substrate inner centromeric protein (INCENP) is present, but the structural and functional characterization of native AURK-B at different pH environment is still unexplored.This study determines the effect of different pH milieu on the structure and function of AURK-B protein wherein the influence of pH on the protein conformation was probed using Circular dichroism (CD) and fluorescence spectroscopy. The structural studies were further combined with functional activity assay to observe the change in kinase activity at various pH milieu (2.0–11.0). CD and fluorescence spectroscopy experiments dictate that at high acidic conditions (pH 2.0 – 5.0), the secondary and tertiary structures of AURK-B become distorted, leading to diminished activity. The protein, however, was observed to stabilize towards pH 7.0 – 8.0 with minimal structure alteration over the basic pH range (pH 9.0 –11.0). The measured spectroscopic structural features were found to be in-line with obtained experimental kinase activity assays.Further, in-vitro experiments indicate that the enzyme is maximally active at pH 8.0. More ordered conformation and compact structure was observed at this pH (pH 8.0) as compared to other pH values through molecular dynamics simulation studies (MDS). As AURK-B localizes itself in the intracellular compartment, this study may provide a clue about the role of different pH environments in enhancing cancer growth, proliferation, and invasion.

Single-cell multi-omics analysis of human testicular germ cell tumor reveals its molecular features and microenvironment

Seminoma is the most common malignant solid tumor in 14 to 44 year-old men. However, its molecular features and tumor microenvironment (TME) is largely unexplored. Here, we perform a series of studies via genomics profiling (single cell multi-omics and spatial transcriptomics) and functional examination using seminoma samples and a seminoma cell line. We identify key gene expression programs share between seminoma and primordial germ cells, and further characterize the functions of TFAP2C in promoting tumor invasion and migration. We also identify 15 immune cell subtypes in TME, and find that subtypes with exhaustion features were located closer to the tumor region through combined spatial transcriptome analysis. Furthermore, we identify key pathways and genes that may facilitate seminoma disseminating beyond the seminiferous tubules. These findings advance our knowledge of seminoma tumorigenesis and produce a multi-omics atlas of in situ human seminoma microenvironment, which could help discover potential therapy targets for seminoma.

SPTBN1 Mediates the Cytoplasmic Constraint of PTTG1, Impairing Its Oncogenic Activity in Human Seminoma.

Seminoma is the most common testicular cancer. Pituitary tumor-transforming gene 1 (PTTG1) is a securin showing oncogenic activity in several tumors. We previously demonstrated that nuclear PTTG1 promotes seminoma tumor invasion through its transcriptional activity on matrix metalloproteinase 2 (MMP-2) and E-cadherin (CDH1). We wondered if specific interactors could affect its subcellular distribution. To this aim, we investigated the PTTG1 interactome in seminoma cell lines showing different PTTG1 nuclear levels correlated with invasive properties. A proteomic approach upon PTTG1 immunoprecipitation uncovered new specific securin interactors. Western blot, confocal microscopy, cytoplasmic/nuclear fractionation, sphere-forming assay, and Atlas database interrogation were performed to validate the proteomic results and to investigate the interplay between PTTG1 and newly uncovered partners. We observed that spectrin beta-chain (SPTBN1) and PTTG1 were cofactors, with SPTBN1 anchoring the securin in the cytoplasm. SPTBN1 downregulation determined PTTG1 nuclear translocation, promoting its invasive capability. Moreover, a PTTG1 deletion mutant lacking SPTBN1 binding was strongly localized in the nucleus. The Atlas database revealed that seminomas that contained higher nuclear PTTG1 levels showed significantly lower SPTBN1 levels in comparison to non-seminomas. In human seminoma specimens, we found a strong PTTG1/SPTBN1 colocalization that decreases in areas with nuclear PTTG1 distribution. Overall, these results suggest that SPTBN1, along with PTTG1, is a potential prognostic factor useful in the clinical management of seminoma.

Determination of Hippo Signaling Pathway in Human Testis, Embryonal Carcinoma and Seminoma

Determination of Hippo Signaling Pathway in Human Testis, Embryonal Carcinoma and Seminoma

P-049 Verteporfin suppresses cell proliferation, survival and migration of TCam-2 Human Seminoma Cells via inhibits the YAP-TEAD complex

Abstract Study question Does verteporfin administration effect on proliferation, survival and migration of TCam-2 human seminoma cells? Summary answer Verteporfin may be a promising anticancer agent for TCam-2 human seminoma cells via inhibition of cell viability, proliferation, migration and stimulation of apoptosis. What is known already Seminoma is germ cell tumor of the testis and TCam-2 cells is the first seminoma-derived cell line that retains many of the characteristic traits of seminoma. The Hippo signalling is a evolutionarily highly conserved pathway that controls organ size, tissue homeostasis, and cancer development. In mammals, the Hippo pathway consists of the serine/threonine kinases Mammalian Sterile 20-protein Kinase 1 and 2 (MST1/2), Large Tumor Suppressor Homologues 1 and 2 (LATS1/2), Yes-Associated Protein (YAP), and its transcriptional cofactor TAZ. Verteporfin inhibits YAP–TEAD complex, blocking cell proliferation and survival. Study design, size, duration TCam-2 cells were treated with different concentrations of verteporfin (1, 5, 10, 20 and 40 µM) for 24, 48 and 72 hours (h). Participants/materials, setting, methods TCam-2 cells were treated with verteporfin at different doses and incubation times. Afterwards, protein expression of Hippo pathway proteins was determined by western blot, mRNA levels were analyzed by qRT-PCR and protein localizations were evaluated by immunoflourescence staining. Cell migration was determinated with wound-healing scratch assay; cell viability, early-late apoptosis and necrosis rates were evaluated by flow cytometry. Main results and the role of chance We detected that 40 μM verteporfin decreased LATS1/2 and p-LATS1/2 protein expression after 48h and 72h treatment (p < 0.05, **p<0.01). MST1/2 and p-MST1/2 was significantly decreased in groups treated with 20 and 40 µM verteporfin after 48 and 72 h of treatment (p < 0.05, ****p<0.0001). YAP expression decreased at 5, 20 and 40 μM verteporfin treatment after 48h and all verteporfin concentrations after 72h (**p<0.01, ***p<0.001, ****p<0.0001). p-YAP expression significantly decreased at all verteporfin concentrations after 48h and only at 40 μM concentrations after 72h (**p<0.01). TEAD4 expression decreased at all verteporfin concentrations after 48 and 72h (****p<0.0001). After 48 and 72h of verteporfin treatment, no significant difference was observed in the expression of the MST1, MST2, LATS1, LATS2 and YAP1 mRNA levels in TCam-2 cells, while TEAD4 mRNA expression level was significantly decreased at 20 and 40 µM compared to control (**p<0.01, ***p<0.001). We also showed that Hippo signaling pathway proteins localized in the cell nucleus especially YAP1 and TEAD4, were translocated to cytoplasm depending on the increasing dose of verteporfin in TCam-2 cells. Verteporfin decreased cell proliferation (****p<0.0001), migration and cell viability (****p<0.0001), as well as increased the early-late apoptosis (**p<0.01, ***p<0.001, ****p<0.0001) in TCam-2 human seminoma cells dose-dependent manner. Limitations, reasons for caution The TCam-2 cell line was gifted by Prof. Dr. Hubert Schorle (Department of Developmental Pathology and Institute of Molecular Diagnostic Pathology, Faculty of Medicine, Germany, Bonn) to our laboratory. There is no limitation in the scope of the study. Wider implications of the findings We determined for the first time the effect of verteporfin treatment on the protein expression and mRNA levels of Hippo signaling pathway in TCam-2 human seminoma cells. We suggested that Hippo pathway and verteporfin relationship may be a therapeutic target for seminoma by affecting cell proliferation, survival, migration and apoptosis. Trial registration number not applicable

Loss of liver kinase B1 in human seminoma.

Testicular cancer is a common malignancy of young males and is believed to be originated from defective embryonic or adult germ cells. Liver kinase B1 (LKB1) is a serine/threonine kinase and a tumor suppressor gene. LKB1 is a negative regulator of the mammalian target of rapamycin (mTOR) pathway, often inactivated in many human cancer types. In this study, we investigated the involvement of LKB1 in the pathogenesis of testicular germ cell cancer. We performed immunodetection of LKB1 protein in human seminoma samples. A 3D culture model of human seminoma was developed from TCam-2 cells, and two mTOR inhibitors were tested for their efficacy against these cancer cells. Western blot and mTOR protein arrays were used to show that these inhibitors specifically target the mTOR pathway. Examination of LKB1 showed reduced expression in germ cell neoplasia in situ lesions and seminoma compared to adjacent normal-appearing seminiferous tubules where the expression of this protein was present in the majority of germ cell types. We developed a 3D culture model of seminoma using TCam-2 cells, which also showed reduced levels of LKB1 protein. Treatment of TCam-2 cells in 3D with two well-known mTOR inhibitors resulted in reduced proliferation and survival of TCam-2 cells. Overall, our results support that downregulation or loss of LKB1 marks the early stages of the pathogenesis of seminoma, and the suppression of downstream signaling to LKB1 might be an effective therapeutic strategy against this cancer type.

Effect of rapamycin treatment in human seminoma TCam-2 cells through inhibition of G1-S transition.

Mammalian target of rapamycin (mTOR) is an important serine/threonine kinase that plays a critical role in several processes including cell cycle, protein synthesis, and energy metabolism. Due to its multiple roles and general dysregulation in cancer, the mTOR pathway is an important target in cancer therapy. However, studies on mTOR activity in seminoma are limited. Therefore, our aim was to investigate the expression of mTOR signaling pathway proteins in the TCam-2 cell line after rapamycin treatment. TCam-2 cells were treated with different concentrations of rapamycin (control (no rapamycin treatment), 4 nM, 20 nM, 100 nM, 500 nM, and 1000 nM rapamycin) for 48 h and 72 h. mTOR, p-mTOR, P70S6K, p-P70S6K, proliferating cell nuclear antigen (PCNA), and caspase-3 expression levels were analyzed by western blot. Apotosis and cell cycle were analyzed by flow cytometry. After 48 h of rapamycin administration, mTOR activity was significantly decreased at 1000 nM (p < 0.05). In addition, P70S6K acitivity significantly decreased in groups at all rapamycin concentrations (***p < 0.001, ****p < 0.0001). After 72 h of rapamycin administration, mTOR pathway activity were significantly decreased at 100, 500, and 1000 nM rapamycin-treated groups (p < 0.05). Moreover, P70S6K expression decreased in all treatment groups (****p < 0.0001). Caspase-3 expression were similar in all groups. While PCNA expression tended to decrease at 48 h in a dose-dependent manner, this decrease was not significant. We detected decreased PCNA expression at 1000 nM rapamycin at 72 h (p < 0.05). The rate of apoptosis increased especially at 1000 nM rapamycin at 72 h (***p < 0.001). On the other hand, according to the results of the cell cycle experiment, G1 phase arrest was detected at all rapamycin doses at 48 and 72 h (***p < 0.001). Our study indicated that 1000 nM rapamycin may inhibit TCam-2 seminoma cells growth by halting cell proliferation through inhibition of G1-S transition. Therefore, we believe that the findings obtained will contribute to the development of new treatment approaches for seminoma patients in the future and in the process of restoring testicular functions and preserving fertility.

First cytogenomic characterization of murine testis tumor cell line MLTC-1

The cell line MLTC-1 was established in 1982 as a transplantable Leydig cell tumor from a C57BL/6 mouse. The cell line has already been applied in &amp;gt;100 studies: still, the only information about its genetic content is given in the first description: MLTC-1 initially had a polyploid karyotype. Here, a molecular karyotyping and multicolor banding-based molecular cytogenetic study was done to provide the first chromosomal/ (molecular) cytogenetic characterization of MLTC-1. A hexaploid karyotype with 72 to 105 chromosomes was hereby characterized. Besides polyploidy, unbalanced two- and three-way translocations, dicentrics and one neocentric derivative were identified. Also, no Y-chromosome could be detected in this clearly male derived cell line. Overall, a completely unbalanced genome is present in MLTC-1 with ~20 regions being subject to copy number losses or gains. After translating these imbalances into the human genome in a standardized way, a 40% match of imbalances with human Leydig cell tumors was evident; however, about the same rate of concordance was detectable for human spermatocytic seminomas and non-seminomas as well as testicular germ cell tumor. Accordingly, MLTC-1 is better suited as an advanced testicular germ cell tumor model in general, rather than specifically for human Leydig cell tumors.

PTTG1/ZEB1 Axis Regulates E-Cadherin Expression in Human Seminoma.

Simple SummarySeminoma represents one of the most common neoplasms in Caucasian males between 15 and 40 years old. The molecular pathways underlying its clinical behavior are far from being understood yet. We previously demonstrated that nuclear Pituitary-tumor transforming-gene 1 (PTTG1), overexpressed in several neoplasms, promotes invasiveness through its transcriptional target matrix-metalloproteinase-2 (MMP2). PTTG1 sustains the migratory and invasive properties of cancer cells through the induction of the epithelial-to-mesenchymal transition (EMT). E-Cadherin (E-CAD) repression is the first step of EMT. Therefore, we investigated the role of PTTG1 in EMT in human seminoma using an in vitro and in vivo model and through Atlas database interrogation. Our data showed a PTTG1-mediated E-CAD transcriptional repression through Zinc finger E-box binding homeobox 1 (ZEB1), a master regulator of the EMT process. Our data provide insights into the molecular characterization of seminoma, promoting PTTG1 as a prognostic marker useful in human seminoma clinical management.(1) Background: PTTG1 sustains the EMT process and the invasiveness of several neoplasms. We previously showed the role of nuclear PTTG1 in promoting invasiveness, through its transcriptional target MMP2, in seminoma in vitro models. Here, we investigated the key players involved in PTTG1-mediated EMT in human seminoma. (2) Methods: Two seminoma cell lines and four human seminoma tumor specimens were used. E-Cadherin gene regulation was investigated using Western blot, real-time PCR, and luciferase assay. Immunoprecipitation, ChIP, RE-ChIP, and confocal microscopy analysis were performed to evaluate the interplay between PTTG1 and ZEB1. Matrigel invasion and spheroid formation assays were applied to functionally investigate PTTG1 involvement in the EMT of seminoma cell lines. RNA depletion and overexpression experiments were performed to verify the role of PTTG1/ZEB1 in E-Cadherin repression and seminoma invasiveness. E-Cadherin and ZEB1 levels were analyzed in human testicular tumors from the Atlas database. (3) Results: PTTG1 transcriptionally represses E-Cadherin in seminoma cell lines through ZEB1. The cooperation of PTTG1 with ZEB1 has a significant impact on cell growth/invasion properties involving the EMT process. Analysis of the Atlas database of testicular tumors showed significantly lower E-Cadherin levels in seminoma, where PTTG1 showed nuclear staining. Finally, PTTG1 and ZEB1 strongly localize together in the periphery of the tumors. (4) Conclusions: These results strengthen the evidence for a role of PTTG1 in the EMT process in human seminomas through its cooperation with the transcriptional repressor ZEB1 on the E-Cadherin gene. Our data enrich the molecular characterization of seminoma, suggesting that PTTG1 is a prognostic factor in seminoma clinical management.

The President's Hat.

<h3>ABSTRACT</h3> The hominoid-specific endogenous retrovirus LTR5_Hs is transcriptionally activated in human primordial germ cell-like cells (hPGCLCs), a pluripotent stem cell-derived cell culture model of PGCs. Here, taking the unique advantage of our novel cell culture method to obtain large amounts of pure hPGCLCs, we performed proteomics profiling of hPGCLCs and detected various viral proteins produced from the LTR5_Hs RNA <i>via</i> ribosomal frameshifting. We also present transmission electron microscopy images of 100-nm diameter virus-like particles (VLPs) assembled at the surface of hPGCLCs. Compared to hPGCLCs, expression of LTR5_Hs RNA is far weaker in human seminomas, the germ cell tumors resembling PGCs. Re-analysis of published single cell RNA-seq data of human embryos revealed strong activation of LTR5_Hs in migrating PGCs but suppressed in PGCs upon they reach the gonadal anlagen. In the microfluidics-supported polarized embryoids mimicking peri-implantation stages of human embryos, LTR5_Hs RNA was detected by RNA in situ hybridization in NANOG⁺/TFAP2C⁺/SOX17⁺ cells resembling freshly emerged PGCs. These results support that human germ cells produce LTR5_Hs proteins and VLPs during their earliest stages of normal development until their settlement in the gonadal anlagen. <h3>SUMMARY STATEMENT</h3> The hominoid-specific endogenous retrovirus LTR5_Hs is activated in a cell culture model resembling early-stage human primordial germ cells, producing not only viral RNA but also retrovirus proteins and virus-like particles.

First Cytogenomic Characterization of the Murine Testicular Tumor Cell Line I-10

After being established in 1967, the commercially available murine Leydig cell tumor line I-10 has been used in almost 50 published studies. I-10 has not been characterized, either at the chromosomal/ cytogenetic level or the genetic level, similar to many other murine tumor cell lines. In this study, we performed molecular karyotyping and multicolor banding-based molecular cytogenetics. A slightly hyperdiploid karyotype with 43 chromosomes was described. The main aberrations comprised several unbalanced translocations and three unusual rearrangements (two dicentric derivatives and one neocentric derivative). Nine regions showed copy number gains, and only five small chromosomal parts showed loss of copy numbers. A standardized translation of these imbalances in the human genome was performed, which showed a 63% overlap of the detected imbalances with testicular germ cell tumors, a 53% concordance with human spermatocytic seminomas and non-seminomas, and only a 36% overlap (approx.) of large copy number gains and losses were similar to the corresponding human Leydig cell tumors. However, no Y-chromosome was detected in this male-derived cell line. Overall, the I-10 cell line was found to be a testicular germ cell tumor model and cannot be treated as a model that is specific to human Leydig cell tumors. At best, it might be suited as a model for an early onset of Leydig cell tumors.

A Coculture Model Mimicking the Tumor Microenvironment Unveils Mutual Interactions between Immune Cell Subtypes and the Human Seminoma Cell Line TCam-2.

Testicular germ cell cancer (TGCC) is the most common type of cancer in young men. Seminomas account for around half of them and are characterized by a pronounced infiltration of immune cells. So far, the impact of the tumor microenvironment (TME) on disease progression, especially the interaction of individual immune cell subtypes with the tumor cells, remains unclear. To address this question, we used an in vitro TME model involving the seminoma-derived cell line Tcam-2 and immune cell subsets purified from human peripheral blood. T cells and monocytes were strongly activated when individually cocultured with Tcam-2 cells as revealed by increased expression of activation markers and pro-inflammatory cytokines both on the mRNA and protein level. Importantly, the interaction between tumor and immune cells was mutual. Gene expression of pluripotency markers as well as markers of proliferation and cell cycle activity were upregulated in Tcam-2 cells in cocultures with T cells, whereas gene expression of SOX17, a marker for seminomas, was unaltered. Interestingly, the impact of monocytes on gene expression of Tcam-2 cells was less pronounced, indicating that the effects of individual immune cell subsets on tumor cells in the TME are highly specific. Collectively, our data indicate that seminoma cells induce immune cell activation and thereby generate a strong pro-inflammatory milieu, whereas T cells conversely increase the proliferation, metastatic potential, and stemness of tumor cells. Although the employed model does not fully mimic the physiological situation found in TGCC in vivo, it provides new insights potentially explaining the connection between inflammatory infiltrates in seminomas and their tendency to burn out and metastasize.

GPR30: A new potential therapeutic target in human testicular germ cell tumors

The G protein-coupled estrogen receptor (GPR30) is suggested to exert a role in non-nuclear estrogen signalling and is over-expressed in a variety of hormone dependent tumors. It is well known that estrogens and xenoestrogens are involved in testicular germ cell tumorigenesis. Different studies show that down regulation of estrogen receptor β (ERβ) associates with GPR30 over-expression both in human testicular carcinoma in situ (CIS) and seminomas and that the mitogenic role exerted by 17β-oestradiol induces the activation of extracellular signal-regulated kinase 1/2 (ERK1/2) through GPR30. In conclusion, the exposure to oestrogens or oestrogen-mimics, in some as of yet undefined manner, diminishes the ERβ-mediated growth restraint in CIS and in human testicular seminoma, indicating that GPR30 could be considered a potential therapeutic target to design specific inhibitors.

MP40-04 NOVEL SELECTIVE LYSINE-SPECIFIC DEMETHYLASE 1 INHIBITORS, NCL1 AND NCD38, SUPPRESS TESTICULAR TUMOR CELL PROLIFERATION

You have accessJournal of UrologyPenile & Testicular Cancer I (MP40)1 Sep 2021MP40-04 NOVEL SELECTIVE LYSINE-SPECIFIC DEMETHYLASE 1 INHIBITORS, NCL1 AND NCD38, SUPPRESS TESTICULAR TUMOR CELL PROLIFERATION Toshiki Etani, Taku Naiki, Nobuhiko Shimizu, Yusuke Noda, Takashi Nagai, Satoshi Nozaki, Keitaro Iida, Ryosuke Ando, Noriyasu Kawai, Satoru Takahashi, Takayoshi Suzuki, and Takahiro Yasui Toshiki EtaniToshiki Etani More articles by this author , Taku NaikiTaku Naiki More articles by this author , Nobuhiko ShimizuNobuhiko Shimizu More articles by this author , Yusuke NodaYusuke Noda More articles by this author , Takashi NagaiTakashi Nagai More articles by this author , Satoshi NozakiSatoshi Nozaki More articles by this author , Keitaro IidaKeitaro Iida More articles by this author , Ryosuke AndoRyosuke Ando More articles by this author , Noriyasu KawaiNoriyasu Kawai More articles by this author , Satoru TakahashiSatoru Takahashi More articles by this author , Takayoshi SuzukiTakayoshi Suzuki More articles by this author , and Takahiro YasuiTakahiro Yasui More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002055.04AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Lysine-specific demethylase 1 (LSD1), the first histone demethylase to be discovered, is a novel target in prostate cancer therapy. NCL1 and NCD38, novel selective cell-active inhibitors of LSD1, were discovered at our university. We analyzed the efficacy of LSD1 inhibitors in germ cell tumors in vitro and in vivo. METHODS: Various tests were used to uncover mechanism of germ cell tumor growth and anticancer effects of NCL1 and NCD38. Cell viability was assessed using a WST-8 assay with standard vehicle, NCL1 or NCD38 in NTERA2 and Tera-1 cells (human testicular embryonal carcinoma cell lines). Flow cytometry and western blotting were performed to assess apoptosis and the cell cycle after treatment of NTERA2 cells with NCL1 or NCD38. Subcutaneous and orthotopic tumors were induced by injecting nude mice with NTERA2 cells. Thereafter, mice were injected intraperitoneally with vehicle, NCL1 or NCD38, twice a week, and their subsequent growth recorded. TUNEL staining was used to detect apoptosis in tumors. Finally, tissue arrays were prepared from tissue specimens from 35 patients with seminoma who underwent orchiectomy. RESULTS: The WST assay revealed a reduction in the number of viable cells in a dose-dependent manner after NCL1 or NCD38 treatment. In western blotting, NCL1 or NCD38 treatment induced caspase-dependent apoptosis, while Oct 3/4 and SOX2 expression was decreased. In ChIP-qPCR analysis, LSD1 inhibition increased the methylation of promoter regions of SOX2 and Oct 3/4. In flow cytometry analysis, NCL1 or NCD38 significantly induced apoptosis in a dose-dependent manner. Subcutaneous tumor volumes and serum AFP levels were significantly lower in mice treated with NCL1 or NCD38 than in controls. TUNEL analysis showed that NCL1 and NCD38 treatment induced apoptosis in NTERA2 subcutaneous tumors. Tissue array analysis showed that LSD1 expression in human seminoma specimens was significantly higher than that in noncancerous specimens. CONCLUSIONS: Germ cell tumor growth was effectively suppressed with NCL1 or NCD38 treatment in vitro and in vivo without adverse events by regulating apoptosis and suppressing SOX2 and Oct4. These results indicate the potential of NCL1 and NCD38 as therapeutic agents for germ cell tumors. Source of Funding: Grants in Aid for Scientific Research (KAKENHI), Japan Society for the Promotion of Science (JSPS), Number 17K11152 © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e715-e716 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Toshiki Etani More articles by this author Taku Naiki More articles by this author Nobuhiko Shimizu More articles by this author Yusuke Noda More articles by this author Takashi Nagai More articles by this author Satoshi Nozaki More articles by this author Keitaro Iida More articles by this author Ryosuke Ando More articles by this author Noriyasu Kawai More articles by this author Satoru Takahashi More articles by this author Takayoshi Suzuki More articles by this author Takahiro Yasui More articles by this author Expand All Advertisement Loading ...

TRIM71 Deficiency Causes Germ Cell Loss During Mouse Embryogenesis and Is Associated With Human Male Infertility.

Mutations affecting the germline can result in infertility or the generation of germ cell tumors (GCT), highlighting the need to identify and characterize the genes controlling germ cell development. The RNA-binding protein and E3 ubiquitin ligase TRIM71 is essential for embryogenesis, and its expression has been reported in GCT and adult mouse testes. To investigate the role of TRIM71 in mammalian germ cell embryonic development, we generated a germline-specific conditional Trim71 knockout mouse (cKO) using the early primordial germ cell (PGC) marker Nanos3 as a Cre-recombinase driver. cKO mice are infertile, with male mice displaying a Sertoli cell-only (SCO) phenotype which in humans is defined as a specific subtype of non-obstructive azoospermia characterized by the absence of germ cells in the seminiferous tubules. Infertility in male Trim71 cKO mice originates during embryogenesis, as the SCO phenotype was already apparent in neonatal mice. The in vitro differentiation of mouse embryonic stem cells (ESCs) into PGC-like cells (PGCLCs) revealed reduced numbers of PGCLCs in Trim71-deficient cells. Furthermore, TCam-2 cells, a human GCT-derived seminoma cell line which was used as an in vitro model for PGCs, showed proliferation defects upon TRIM71 knockdown. Additionally, in vitro growth competition assays, as well as proliferation assays with wild type and CRISPR/Cas9-generated TRIM71 mutant NCCIT cells showed that TRIM71 also promotes proliferation in this malignant GCT-derived non-seminoma cell line. Importantly, the PGC-specific markers BLIMP1 and NANOS3 were consistently downregulated in Trim71 KO PGCLCs, TRIM71 knockdown TCam-2 cells and TRIM71 mutant NCCIT cells. These data collectively support a role for TRIM71 in PGC development. Last, via exome sequencing analysis, we identified several TRIM71 variants in a cohort of infertile men, including a loss-of-function variant in a patient with an SCO phenotype. Altogether, our work reveals for the first time an association of TRIM71 deficiency with human male infertility, and uncovers further developmental roles for TRIM71 in the germline during mouse embryogenesis.

GPER and Testicular Germ Cell Cancer.

The G protein-coupled estrogen receptor (GPER), also known as GPR30, is a widely conserved 7-transmembrane-domain protein which has been identified as a novel 17β-estradiol-binding protein that is structurally distinct from the classic oestrogen receptors (ERα and ERβ). There are still conflicting data regarding the exact role and the natural ligand of GPER/GPR30 in reproductive tracts as both male and female knock-out mice are fertile and have no abnormalities of reproductive organs. Testicular germ cell cancers (TGCCs) are the most common malignancy in young males and the most frequent cause of death from solid tumors in this age group. Clinical and experimental studies suggested that estrogens participate in the physiological and pathological control of male germ cell proliferation. In human seminoma cell line, while 17β-estradiol (E2) inhibits in vitro cell proliferation through an ERβ-dependent mechanism, an impermeable E2 conjugate (E2 coupled to BSA), in vitro cell proliferation is stimulated by activating ERK1/2 and protein kinase A through a membrane GPCR that we further identified as GPER/GPR30. The same effect was observed with low but environmentally relevant doses of BPA, an estrogenic endocrine disrupting compound. Furthermore, GPER/GPR30 is specifically overexpressed in seminomas but not in non-seminomas and this overexpression is correlated with an ERβ-downregulation. This GPER/GPR30 overexpression could be linked to some genetic variations, as single nucleotide polymorphisms, which was also reported in other hormone-dependent cancers. We will review here the implication of GPER/GPR30 in TGCCs pathophysiology and the arguments to consider GPER/GPR30 as a potential therapeutic target in humans.

Nuclear Localization of PTTG1 Promotes Migration and Invasion of Seminoma Tumor through Activation of MMP-2.

Simple SummarySeminoma is the most common subtype of testicular germ cell tumors (TGCTs) and its molecular patterns have not been clarified. The pituitary tumor-transforming gene 1 (PTTG1) is a securin and its overexpression is reported in many cancers. We previously demonstrated that PTTG1 is mainly localized at the neoplasm periphery and infiltration area of seminoma. Therefore, we aim to investigate in vitro the role of PTTG1 on the invasive properties of seminoma. Our results elucidate the role of nuclear PTTG1 in promoting invasiveness and the metastatic process of these cells through its transcriptional target matrix-metalloproteinase-2 (MMP-2). Analysis of human testicular tumors from the Atlas database revealed an exclusive PTTG1 nuclear localization and a concomitant increase of MMP-2 levels in seminoma compared to non-seminoma tumors. Our data provide insights into the molecular characterization of seminoma, promoting PTTG1 as a prognostic marker useful in human seminoma clinical management.(1) Background: PTTG1 sustains the invasiveness of several cancer types. We previously reported that in seminomas, PTTG1 was detected in the peripheral area of the tumor and in the leading infiltrative edge. Here, we investigate the PTTG1 role on the invasive properties of seminoma. (2) Methods: three seminoma cell lines were used as in vitro model. PTTG1 levels and localization were investigated by biochemical and immunofluorescence analyses. Wound-healing, Matrigel invasion assays, and zymography were applied to study migratory and invasive capability of the cell lines. RNA interference and overexpression experiments were performed to address the PTTG1 role in seminoma invasiveness. PTTG1 and its target MMP-2 were analyzed in human testicular tumors using the Atlas database. (3) Results: PTTG1 was highly and differentially expressed in the seminoma cell lines. Nuclear PTTG1 was positively correlated to the aggressive phenotype. Its modulation confirms these results. Atlas database analysis revealed that PTTG1 was localized in the nucleus in seminoma compared with non-seminoma tumors, and that MMP-2 levels were significantly higher in seminomas. (4) Conclusions: nuclear PTTG1 promotes invasiveness of seminoma cell lines. Atlas database supported these results. These data lead to the hypothesis that nuclear PTTG1 is an eligible prognostic factor in seminomas.

GCT-22. PROTEIN DEUBIQUITINATION PATHWAY IS A NOVEL THERAPEUTIC TARGET AGAINST MALIGNANT NON-GERMINOMATOUS CNS GERM CELL TUMORS

Central nervous system germ cell tumors (CNSGCTs) are rare intracranial neoplasm usually developed in adolescents and young adults. However, in East Asia including Japan, incidence of CNSGCTs is considerably higher compare with other regions of the world. Whereas germinomas generally respond to chemo-radiotherapy well, malignant subtypes of non-germinomatous germ cell tumors (NGGCT) are refractory, and development of novel therapy against NGGCTs is urgently needed. To develop a new therapeutic strategy against aggressive NGGCTs, we have investigated novel molecular targets for NGGCT treatment. We screened a total of 120 CNSGCT tumor tissues (including 55 NGGCT), which were registered to the Intracranial Germ Cell Tumor Consortium (iGCT), and discovered multiple mutations of a molecule that regulates protein ubiquitination and degradation specifically in NGGCT cases (5 of 55 cases; 1 immature teratoma, 3 mixed gem cell tumors, and 1 embryonal carcinoma). An in vitro ubiquitination assay revealed the mutations of this molecule discovered in NGGCT cases were loss of function mutations. Reduced expression of this molecule by knockdown in an established human seminoma cell line Tcam2 or a human yolk sac tumor cell line YST1, which was recently established in our institute, resulted in enhanced proliferation as well as upregulation of MEK-ERK activation. Importantly, treatment of these two GCT cell lines with reduced expression of this molecule by MEK inhibitor trametinib suppressed augmented proliferation of these cells. Taken together, these results suggest that protein ubiquitination-related pathways as well as MEK-ERK cascade may serve as a novel therapeutic target against NGGCTs.

Filamin A Orchestrates Cytoskeletal Structure, Cell Migration and Stem Cell Characteristics in Human Seminoma TCam-2 Cells.

Filamins are large dimeric F-actin cross-linking proteins, crucial for the mechanosensitive properties of a number of cell types. Due to their interaction with a variety of different proteins, they exert important regulatory functions. However, in the human testis the role of filamins has been insufficiently explored. Immunohistochemical staining of human testis samples identified filamin A (FLNA) in spermatogonia and peritubular myoid cells. Investigation of different testicular tumor samples indicated that seminoma also express FLNA. Moreover, mass spectrometric analyses identified FLNA as one of the most abundant proteins in human seminoma TCam-2 cells. We therefore focused on FLNA in TCam-2 cells, and identified by co-immunoprecipitation LAD1, RUVBL1 and DAZAP1, in addition to several cytoskeletal proteins, as interactors of FLNA. To study the role of FLNA in TCam-2 cells, we generated FLNA-deficient cells using the CRISPR/Cas9 system. Loss of FLNA causes an irregular arrangement of the actin cytoskeleton and mechanical instability, impaired adhesive properties and disturbed migratory behavior. Furthermore, transcriptional activity of typical stem cell factors is increased in the absence of FLNA. In summary, our data suggest that FLNA is crucially involved in balancing stem cell characteristics and invasive properties in human seminoma cells and possibly human testicular germ cells.

CBMS-11 PROTEIN DEUBIQUITINATION PATHWAY IS A NOVEL THERAPEUTIC TARGET AGAINST MALIGNANT CNS NON-GERMINOMATOUS GERM CELL TUMORS

Central nervous system germ cell tumors (CNSGCTs) are rare intracranial neoplasm usually developed in adolescents and young adults. However, in East Asia including Japan, incidence of CNSGCTs is considerably higher compare with other regions of the world. Whereas germinomas generally respond to chemo-radiotherapy well, malignant subtypes of non-germinomatous germ cell tumors (NGGCT) are refractory, and development of novel therapy against NGGCTs is urgently needed. To develop a new therapeutic strategy against aggressive NGGCTs, we have investigated novel molecular targets for NGGCT treatment. We screened a total of 120 CNSGCT tumor tissues (including 55 NGGCT), which were registered to the Intracranial Germ Cell Tumor Consortium (iGCT), and discovered multiple mutations of a molecule that regulates protein ubiquitination and degradation specifically in NGGCT cases (5 of 55 cases; 1 immature teratoma, 3 mixed gem cell tumors, and 1 embryonal carcinoma). An in vitro ubiquitination assay revealed the mutations of this molecule discovered in NGGCT cases were loss of function mutations. Reduced expression of this molecule by knockdown in an established human seminoma cell line Tcam2 or a human yolk sac tumor cell line YST1, which was recently established in our institute, resulted in enhanced proliferation as well as upregulation of MEK-ERK activation. Importantly, treatment of these two GCT cell lines with reduced expression of this molecule by MEK inhibitor trametinib suppressed augmented proliferation of these cells. Taken together, these results suggest that protein ubiquitination-related pathways as well as MEK-ERK cascade may serve as a novel therapeutic target against NGGCTs.