Stem cell factor as a novel diagnostic marker for early malignant germ cells

Testicular Germ Cell Tumor Tissue Biomarker Analysis: A Comparison of Human Protein Atlas and Individual Testicular Germ Cell Tumor Component Immunohistochemistry

The accurate management of testicular germ cell tumors (TGCTs) depends on identifying the individual histological tumor components. Currently available data on protein expression in TGCTs are limited. The human protein atlas (HPA) is a comprehensive resource presenting the expression and localization of proteins across tissue types and diseases. In this study, we have compared the data from the HPA with our in-house immunohistochemistry on core TGCT diagnostic genes to test reliability and potential biomarker genes. We have compared the protein expression of 15 genes in TGCT patients and non-neoplastic testicles with the data from the HPA. Protein expression was converted into diagnostic positivity. Our study discovered discrepancies in three of the six core TGCT diagnostic genes, POU5F1, KIT and SOX17 in HPA. DPPA3, CALCA and TDGF1 were presented as potential novel TGCT biomarkers. MGMT was confirmed while RASSF1 and PRSS21 were identified as biomarkers of healthy testicular tissue. Finally, SALL4, SOX17, RASSF1 and PRSS21 dysregulation in the surrounding testicular tissue with complete preserved spermatogenesis of TGCT patients was detected, a potential early sign of neoplastic transformation. We highlight the importance of a multidisciplinary collaborative approach to fully understand the protein landscape of human testis and its pathologies.

ERK Signaling Pathway Is Constitutively Active in NT2D1 Non-Seminoma Cells and Its Inhibition Impairs Basal and HGF-Activated Cell Proliferation

c-MET/hepatocyte growth factor (HGF) system deregulation is a well-known feature of malignancy in several solid tumors, and for this reason this system and its pathway have been considered as potential targets for therapeutic purposes. In previous manuscripts we reported c-MET/HGF expression and the role in testicular germ cell tumors (TGCTs) derived cell lines. We demonstrated the key role of c-Src and phosphatidylinositol 3-kinase (PI3K)/AKT adaptors in the HGF-dependent malignant behavior of the embryonal carcinoma cell line NT2D1, finding that the inhibition of these onco-adaptor proteins abrogates HGF triggered responses such as proliferation, migration, and invasion. Expanding on these previous studies, herein we investigated the role of mitogen-activated protein kinase (MAPK)/extracellular signal regulated kinase (ERK) pathways in the HGF-dependent and HGF-independent NT2D1 cells biological responses. To inhibit MAPK/ERK pathways we chose a pharmacological approach, by using U0126 inhibitor, and we analyzed cell proliferation, collective migration, and chemotaxis. The administration of U0126 together with HGF reverts the HGF-dependent activation of cell proliferation but, surprisingly, does not exert the same effect on NT2D1 cell migration. In addition, we found that the use of U0126 alone significantly promotes the acquisition of NT2D1 «migrating phenotype», while collective migration of NT2D1 cells was stimulated. Notably, the inhibition of ERK activation in the absence of HGF stimulation resulted in the activation of the AKT-mediated pathway, and this let us speculate that the paradoxical effects obtained by using U0126, which are the increase of collective migration and the acquisition of partial epithelium-mesenchyme transition (pEMT), are the result of compensatory pathways activation. These data highlight how the specific response to pathway inhibitors, should be investigated in depth before setting up therapy.

Analysis of connexin 43, connexin 45 and N-cadherin in the human sertoli cell line FS1 and the human seminoma-like cell line TCam-2 in comparison with human testicular biopsies

BACKGROUND

Germ cell tumors are relatively common in young men. They derive from a non-invasive precursor, called germ cell neoplasia in situ, but the exact pathogenesis is still unknown. Thus, further understanding provides the basis for diagnostics, prognostics and therapy and is therefore paramount. A recently developed cell culture model consisting of human FS1 Sertoli cells and human TCam-2 seminoma-like cells offers new opportunities for research on seminoma. Since junctional proteins within the seminiferous epithelium are involved in cell organization, differentiation and proliferation, they represent interesting candidates for investigations on intercellular adhesion and communication in context with neoplastic progression.

METHODS

FS1 and TCam-2 cells were characterized regarding gap-junction-related connexin 43 (Cx43) and connexin 45 (Cx45), and adherens-junction-related N-cadherin using microarray, PCR, Western blot, immunocytochemistry and immunofluorescence. Results were compared to human testicular biopsies at different stages of seminoma development via immunohistochemistry to confirm the cell lines' representativeness. Furthermore, dye-transfer measurements were performed to investigate functional cell coupling.

RESULTS

Cx43, Cx45 and N-cadherin mRNA and protein were generally detectable in both cell lines via qualitative RT-PCR and Western blot. Immunocytochemistry and immunofluorescence revealed a mainly membrane-associated expression of N-cadherin in both cell lines, but gene expression values were higher in FS1 cells. Cx43 expression was also membrane-associated in FS1 cells but barely detectable in TCam-2 cells. Accordingly, a high gene expression value of Cx43 was measured for FS1 and a low value for TCam-2 cells. Cx45 was primary located in the cytoplasm of FS1 and TCam-2 cells and revealed similar low to medium gene expression values in both cell lines. Overall, results were comparable with corresponding biopsies. Additionally, both FS1 and TCam-2 cells showed dye diffusion into neighboring cells.

CONCLUSION

The junctional proteins Cx43, Cx45 and N-cadherin are expressed in FS1 and TCam-2 cells at mRNA and/or protein level in different amounts and localizations, and cells of both lines are functionally coupled among each other. Concerning the expression of these junctional proteins, FS1 and TCam-2 cells are largely representative for Sertoli and seminoma cells, respectively. Thus, these results provide the basis for further coculture experiments evaluating the role of junctional proteins in context with seminoma progression.

Disorders in the function of Sertoli cells and arrest in the differentiation of gonocytes in patients with cryptochidism and microlithiasis

PURPOSE

This study aimed to correlate the presence of microlithiasis (ML) in cryptorchidism (CO) patients with the functionality of Sertoli cells and the arrest of gonocyte differentiation.

METHODS

Testicular biopsies were obtained from 21 inguinal CO pediatric patients and were classified in two groups as follows: patients with ML and those without ML. In both groups, the number of Sertoli cells/seminiferous cords and their functionality were determined, considering the concentrations of inhibin B. In addition, the area and the histological alterations of seminiferous epithelium were evaluated. The arrest of gonocyte differentiation was determined by immunoreactivity to SALL4, AP2ɣ, PLAP and POU5F1.

RESULTS

We found a statistical correlation between the presence of ML with the alterations in the functionality of Sertoli cells without reflecting in the differentiation of the gonocytes.

CONCLUSION

The study of this population suggests that the association between CO and ML shows a malfunction of the Sertoli cells without necessarily causing arrest in the differentiation of gonocytes in these patients.

Pattern of placental alkaline phosphatase (PLAP) expression in human tumors: a tissue microarray study on 12,381 tumors

Placental alkaline phosphatase (PLAP) is commonly expressed at high levels in testicular germ cell tumors. PLAP immunohistochemistry (IHC) is thus often used to confirm this diagnosis, especially in cases of putative metastasis. However, other tumors can also express PLAP. To comprehensively determine PLAP expression in normal and tumor tissue, a tissue microarray containing 16,166 samples from 131 different tumor types and subtypes as well as 608 samples from 76 different normal tissue types was analyzed by IHC. Moderate to strong PLAP positivity was found in 27 (21%) of 131 different tumor types including seminoma (96%), embryonal carcinoma (85%), and yolk sac tumors of the testis (56%); endometrioid carcinoma of the endometrium (28%) and the ovary (20%); gastric adenocarcinoma (22%); serous carcinoma (not otherwise specified) of the ovary (17%) and the uterus (11%); adenocarcinoma of the ampulla of Vater (15%); carcinosarcoma of the ovary (11%) and the uterus (8%); esophageal adenocarcinoma (10%); invasive urothelial carcinoma (4%); cholangiocarcinoma (2%); and adenocarcinoma of the lung (1%). Low‐level PLAP immunostaining, often involving only a small fraction of tumor cells, was seen in 21 additional tumor entities. The clinical significance of PLAP expression may vary between tumor types as high PLAP expression was linked to advanced pathological tumor stage (p = 0.0086), nodal metastasis (p = 0.0085), and lymphatic (p = 0.0007) and blood vessel invasion (p = 0.0222) in colorectal cancer, but to low pathological tumor stage in endometrial cancer (p = 0.0043). In conclusion, our data identify several tumor entities that can show PLAP expression at comparable levels to testicular germ cell tumors. These tumor entities need to be considered in cases of PLAP‐positive metastasis. Low‐level PLAP expression can be found in various other tumor entities and should generally not be viewed as a strong argument for germ cell neoplasia.

Testicular Tumors: A Contemporary Update on Morphologic, Immunohistochemical and Molecular Features

Testicular tumors are incredibly diverse and one of the most challenging areas in surgical pathology. Because of the rarity and overlapping features with numerous entities occurring in the testis and paratestis, these tumors pose a diagnostic challenge even to the most experienced general pathologists. In 2016, the latest "World Health Organization (WHO) classification of testicular tumors" was released, which incorporated several updates to the previous 2004 classification system. These updates involved several entities, including germ cell tumors, sex cord-stromal tumors, tumors containing both germ cells and sex-cord stromal cells, a miscellaneous group of testicular tumors and paratesticular tumors. In addition, significant changes were also introduced in the 2018 AJCC TNM staging (8th edition) regarding testicular tumors. The germ cell tumors are divided into 2 major groups; tumors derived from germ cell neoplasia in situ (GCNIS) and those unrelated to GCNIS. The GCNIS associated tumors include seminomatous and nonseminomatous germ cell tumors, which constitute a heterogeneous group of tumors. Non-GCNIS-associated tumors include prepubertal-type teratoma, prepubertal yolk sac tumor, mixed prepubertal-type teratoma and yolk sac tumor and spermatocytic seminoma. In the sex cord-stromal category, the tumors are classified based on their cells of origin. Most are Leydig cell tumors and Sertoli cell tumors; however, several mixed and diverse entities based on cell types are included in this group. Gonadoblastoma is the only tumor in the mixed germ cell and sex cord-stromal tumor category. Because of recent advances in molecular techniques, abundant new genetic information has emerged which helped classify the tumors based on the molecular alterations and provided insights into the tumor pathogenesis. This review focused on the updates related to testicular germ cell tumors and sex cord-stromal tumors and described the morphologic, immunohistochemical and molecular characteristics with an aim to provide a practical diagnostic approach and an update on relevant recent molecular advances.

Malignant Germ Cell Tumors and Their Precursor Gonadal Lesions in Patients with XY-DSD: A Case Series and Review of the Literature

The risk of gonadal germ cell tumors is increased over the lifetime of patients with XY-disorders of sex development (XY-DSD). The aim of this study was to evaluate clinical features and histopathological outcome after gonadectomy in patients with XY-DSD to assess the risk of malignant transformation to gonadal germ cell tumors. Thirty-five women treated for XY-DSD at our hospital between 2003 and 2020 were enrolled in this study. Twenty-seven (77%) underwent prophylactic gonadectomy, 10 (29%) at our department and 17 (48%) at external hospitals. Eight (23%) patients didn’t receive gonadectomy. Of the patients who underwent a surgical procedure at our hospital, two patients were diagnosed with a unilateral seminoma, one patient with a bilateral and one patient with a unilateral Sertoli cell adenoma. According to these findings, preventive gonadectomy in patients with XY-DSD should be taken into consideration. Guidelines concerning the necessity of gonadectomy to avoid malignant transformation are still lacking. The risk of malignant germ cell tumors from rudimentary gonads has not been investigated sufficiently to date, as it is mostly based on case series due to the rarity of the condition. In our study we retrospectively analyzed patients who partly underwent bilateral gonadectomy, aiming to fill this gap. Concerning the ideal point of time for gonadectomy, further studies with a higher number of patients are needed.

Molecular Biology of Pediatric and Adult Male Germ Cell Tumors

Simple Summary

Although testicular germ cell tumors (TGCTs) are rare pediatric malignancies, they are the most common malignancies in young adult men. The similarities and differences between TGCTs in adults and children, taking into account the clinic presentation, biology, and molecular changes, are underexplored. In this paper, we aim to provide an overview of the molecular aspects of TGCTs, drawing a parallel between the findings in adult and pediatric groups.

Abstract

Cancer is a leading cause of death by disease in children and the second most prevalent of all causes in adults. Testicular germ cell tumors (TGCTs) make up 0.5% of pediatric malignancies, 14% of adolescent malignancies, and are the most common of malignancies in young adult men. Although the biology and clinical presentation of adult TGCTs share a significant overlap with those of the pediatric group, molecular evidence suggests that TGCTs in young children likely represent a distinct group compared to older adolescents and adults. The rarity of this cancer among pediatric ages is consistent with our current understanding, and few studies have analyzed and compared the molecular basis in childhood and adult cancers. Here, we review the major similarities and differences in cancer genetics, cytogenetics, epigenetics, and chemotherapy resistance between pediatric and adult TGCTs. Understanding the biological and molecular processes underlying TGCTs may help improve patient outcomes, and fuel further investigation and clinical research in childhood and adult TGCTs.

Diagnosis and treatment of the intra-abdominal gonad in the pediatric population: Testes, ovaries, dysgenetic gonads, streaks, and ovotestes

BACKGROUND/PURPOSE

Pediatric surgical specialists are often confronted with the difficult task of identifying, diagnosing and managing intra-abdominal gonads in children. Ranging from the intra-abdominal cryptorchid testis to normal or pathologic ovaries and gonads in disorders of sexual development, all intra-abdominal gonads in the pediatric population pose different diagnosis and management challenges. Understanding the hormonal and fertility potential of the gonad and knowing its potential cancer risk is essential when deciding how to manage these patients. In addition, the ideal surgical management for each one of these patients is often debated.

METHODS

Descriptive literature review.

RESULTS/CONCLUSION

Herein, we reviewed gonadal formation, common etiologies, diagnosis and management of intra-abdominal testes, pathologic ovaries and gonads in disorders of sexual development. Fertility potential and cancer risk for each were also reviewed and how both affect surgical management of the gonad.

TYPE OF STUDY/LEVEL OF EVIDENCE

Review Article, Level V.

Function and transcriptomic dynamics of Sertoli cells during prospermatogonia development in mouse testis

In mammals, spermatogonial stem cells (SSCs) arise from a subpopulation of prospermatogonia during neonatal testis development. Currently, molecular mechanisms directing the prospermatogonia to spermatogonial transition are not well understood. In the study, we found that reducing Sertoli cells number by Amh-cre mediated expression of diphtheria toxin (AC;DTA) in murine fetal testis caused defects in prospermatogonia fate decisions. Histological and immunohistochemical analyses confirmed that Sertoli cells loss occurred at embryonic day (E) 14.5. Prospermatogonia maintained mitotic arrest at E16.5 in control animals, in contrast, 13.4% of germ cells in AC;DTA testis reentered cell cycle and expressed gH2A.X and Sycp3, indicating the commitment to meiosis. After birth, the number of prospermatogonia resuming mitosis was significantly affected by Sertoli cell loss in AC;DTA animals. Lastly, we isolated primary Sertoli cells using a Sertoli cell specific GFP reporter line and showed dynamics of Sertoli cell transcriptomes at E12.5, E13.5, E16.5 and P1. By further analysis, we revealed unique gene expression patterns and potential candidate genes regulating Sertoli cell development and likely mediating interactions between Sertoli cells, prospermatogonia and other testicular cells.

Predicting Gonadal Germ Cell Cancer in People with Disorders of Sex Development; Insights from Developmental Biology

The risk of gonadal germ cell cancer (GGCC) is increased in selective subgroups, amongst others, defined patients with disorders of sex development (DSD). The increased risk is due to the presence of part of the Y chromosome, i.e., GonadoBlastoma on Y chromosome GBY region, as well as anatomical localization and degree of testicularization and maturation of the gonad. The latter specifically relates to the germ cells present being at risk when blocked in an embryonic stage of development. GGCC originates from either germ cell neoplasia in situ (testicular environment) or gonadoblastoma (ovarian-like environment). These precursors are characterized by presence of the markers OCT3/4 (POU5F1), SOX17, NANOG, as well as TSPY, and cKIT and its ligand KITLG. One of the aims is to stratify individuals with an increased risk based on other parameters than histological investigation of a gonadal biopsy. These might include evaluation of defined susceptibility alleles, as identified by Genome Wide Association Studies, and detailed evaluation of the molecular mechanism underlying the DSD in the individual patient, combined with DNA, mRNA, and microRNA profiling of liquid biopsies. This review will discuss the current opportunities as well as limitations of available knowledge in the context of predicting the risk of GGCC in individual patients.

Clinical management in mixed gonadal dysgenesis with chromosomal mosaicism: Considerations in newborns and adolescents

Individuals born on the spectrum of genetic abnormalities known as mixed gonadal dysgenesis (MGD) have a wide range of anatomical findings and management can be challenging in the newborn and adolescent. Historically, many individuals with MGD have undergone gonadectomy to avert the risk of gonadal malignancy. However, gonadectomy deprives patients of the benefits of their endogenous hormones, potential fertility, and in the case with MGD, has historically been done prior to addressing gender identity. Some patient advocates have proposed a delayed approach to surgical reconstructions and/or gonadectomy in other differences/disorders of sex development (DSD), particularly in patients with congenital adrenal hyperplasia and androgen insensitivity syndrome. In many areas of the world, there continues to be a shift toward delayed reconstructions and hesitancy regarding irreversible gonadectomy. To date, no clinical management protocol addressing these issues from a patient-centered approach has been described. We review what is known about malignancy risk and propose a management protocol for those with MGD that involves shared decision making regarding the gonads and addresses the long-term challenges with regard to gender and anatomy.

Human germ cell tumours from a developmental perspective

Human germ cell tumours (GCTs) are derived from stem cells of the early embryo and the germ line. They occur in the gonads (ovaries and testes) and also in extragonadal sites, where migrating primordial germ cells are located during embryogenesis. This group of heterogeneous neoplasms is unique in that their developmental potential is in effect determined by the latent potency state of their cells of origin, which are reprogrammed to omnipotent, totipotent or pluripotent stem cells. Seven GCT types, defined according to their developmental potential, have been identified, each with distinct epidemiological and (epi)genomic features. Heritable predisposition factors affecting the cells of origin and their niches likely explain bilateral, multiple and familial occurrences of the different types of GCTs. Unlike most other tumour types, GCTs are rarely caused by somatic driver mutations, but arise through failure to control the latent developmental potential of their cells of origin, resulting in their reprogramming. Consistent with their non-mutational origin, even the malignant tumours of the group are characterized by wild-type TP53 and high sensitivity for DNA damage. However, tumour progression and the rare occurrence of treatment resistance are driven by embryonic epigenetic state, specific (sub)chromosomal imbalances and somatic mutations. Thus, recent progress in understanding GCT biology supports a comprehensive developmental pathogenetic model for the origin of all GCTs, and provides new biomarkers, as well as potential targets for treatment of resistant disease.

Mechanisms of extramedullary relapse in acute lymphoblastic leukemia: Reconciling biological concepts and clinical issues

Long-term survival rates in childhood acute lymphoblastic leukemia (ALL) are currently above 85% due to huge improvements in treatment. However, 15-20% of children still experience relapses. Relapses can either occur in the bone marrow or at extramedullary sites, such as gonads or the central nervous system (CNS), formerly referred to as ALL-blast sanctuaries. The reason why ALL cells migrate to and stay in these sites is still unclear. In this review, we have attempted to assemble the evidence concerning the microenvironmental factors that could explain why ALL cells reside in such sites. We present criteria that make extramedullary leukemia niches and solid tumor metastatic niches comparable. Indeed, considering extramedullary leukemias as metastases could be a useful approach for proposing more effective treatments. In this context, we conclude with several examples of potential niche-based therapies which could be successfully added to current treatments of ALL.

Different Clinical Presentations and Management in Complete Androgen Insensitivity Syndrome (CAIS)

Complete androgen insensitivity syndrome (CAIS) is an X-linked recessive genetic disorder resulting from maternally inherited or de novo mutations involving the androgen receptor gene, situated in the Xq11-q12 region. The diagnosis is based on the presence of female external genitalia in a 46, XY human individual, with normally developed but undescended testes and complete unresponsiveness of target tissues to androgens. Subsequently, pelvic ultrasound or magnetic resonance imaging (MRI) could be helpful in confirming the absence of Mullerian structures, revealing the presence of a blind-ending vagina and identifying testes. CAIS management still represents a unique challenge throughout childhood and adolescence, particularly regarding timing of gonadectomy, type of hormonal therapy, and psychological concerns. Indeed this condition is associated with an increased risk of testicular germ cell tumour (TGCT), although TGCT results less frequently than in other disorders of sex development (DSD). Furthermore, the majority of detected tumoral lesions are non-invasive and with a low probability of progression into aggressive forms. Therefore, histological, epidemiological, and prognostic features of testicular cancer in CAIS allow postponing of the gonadectomy until after pubertal age in order to guarantee the initial spontaneous pubertal development and avoid the necessity of hormonal replacement therapy (HRT) induction. However, HRT is necessary after gonadectomy in order to prevent symptoms of hypoestrogenism and to maintain secondary sexual features. This article presents differential clinical presentations and management in patients with CAIS to emphasize the continued importance of standardizing the clinical and surgical approach to this disorder.

Malignant testicular germ cell tumors in postpubertal individuals with androgen insensitivity: prevalence, pathology and relevance of single nucleotide polymorphism-based susceptibility profiling

STUDY QUESTION

What is the prevalence of malignant testicular germ cell tumors (TGCT) and its precursors, (pre-) germ cell neoplasia in situ (GCNIS), in late teenagers and adults who have androgen insensitivity syndrome (AIS) and the impact of an individual's genetic susceptibility to development of TGCT?

SUMMARY ANSWER

No GCNIS or TGCT was diagnosed, but pre-GCNIS was identified in 14 and 10% of complete and partial AIS patients, respectively, and was associated with a higher genetic susceptibility score (GSS), with special attention for KITLG (rs995030) and ATFZIP (rs2900333).

WHAT IS KNOWN ALREADY

Many adult women with AIS decline prophylactic gonadectomy, while data regarding the incidence, pathophysiology and outcomes of TGCT in postpubertal individuals with AIS are lacking. The relevance of genetic factors, such as single nucleotide polymorphisms (SNPs), in predisposing AIS individuals to TGCT is unknown.

STUDY DESIGN, SIZE, DURATION

This multicenter collaborative study on prophylactically removed gonadal tissue was conducted in a pathology lab specialized in germ cell tumor biology.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Material from 52 postpubertal individuals with molecularly confirmed AIS (97 gonadal samples) was included; the median age at surgery was 17.5 (14-54) years. Immunohistochemical studies and high-throughput profiling of 14 TGCT-associated SNPs were performed. The main outcome measures were the prevalence of pre-GCNIS, GCNIS and TGCT, and its correlation with a GSS, developed based on the results of recent genome-wide association studies.

MAIN RESULTS AND ROLE OF CHANCE

The earliest recognizable change preceding GCNIS, referred to as pre-GCNIS, was present in 14% of individuals with complete and 10% of those with partial AIS at a median age of 16 years. No GCNIS or invasive TGCT were found. The median GSS was significantly greater for those with, compared to those without, pre-GCNIS (P = 0.01), with an overlap between groups. Our data suggest important roles for risk alleles G at KITLG (rs995030) and C at ATFZIP (rs2900333), among the 14 studied TGCT-associated SNPs.

LARGE SCALE DATA

N/A.

LIMITATIONS REASONS FOR CAUTION

A limited number of cases were included.

WIDER IMPLICATIONS OF THE FINDINGS

Our data suggest that the prevalence of pre-GCNIS in individuals with AIS beyond puberty is around 15%. Genetic susceptibility likely contributes to pre-GCNIS development in AIS but factors related to malignant progression remain unclear. Although data in older patients remain scarce, malignant progression appears to be a rare event, although the natural history of the premalignant lesion remains unknown. Therefore, the practice of routine prophylactic gonadectomy in adults with AIS appears questionable and the patient's preference, after having been fully informed, should be decisive in this matter.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by research grants from the Research Foundation Flanders (FWO) (to M.C.), the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq G0D6713N) (to B.B.M. and M.C.) and the European Society for Pediatric Endocrinology (ESPE), granted by Novo Nordisk AB (to J.K.). There are no competing interests.

Recently Described and Clinically Important Entities in Testis Tumors: A Selective Review of Changes Incorporated Into the 2016 Classification of the World Health Organization

Context.—

In 2016 the World Health Organization published a revised classification of testicular neoplasms based upon advances in understanding their pathogenesis and molecular biology. The rationale for this revision and additional clinically relevant observations were the topics of a talk given to the Houston Society of Clinical Pathologists in April 2017. This paper summarizes that talk.

Objective.—

To summarize and explain the most important changes to the classification of testicular neoplasms in the World Health Organization 2016 revision.

Data Sources.—

Peer-reviewed published literature and contributions by individuals with expertise in this area that were also reviewed by genitourinary pathologists.

Conclusions.—

Most changes occurred in the germ cell tumor classification, including replacement of the terms intratubular germ cell neoplasia unclassified and carcinoma in situ by germ cell neoplasia in situ; subdivision of the tumors into 2 main categories, those derived from germ cell neoplasia in situ and those not derived from germ cell neoplasia in situ; distinction of germ cell neoplasia in situ from germ cells with delayed maturation and pre–germ cell neoplasia in situ; expansion of the trophoblastic tumor category to include epithelioid trophoblastic tumor and cystic trophoblastic tumor; and substitution of spermatocytic tumor for spermatocytic seminoma and its placement in the non–germ cell neoplasia in situ group. Other revisions included eliminating sclerosing Sertoli cell tumor as a distinct entity; the recognition of intratubular hyalinizing Sertoli cell tumor; and acceptance of the role of undifferentiated gonadal tissue in the pathogenesis of gonadoblastoma.

Pediatric Germ Cell Tumors: A Developmental Perspective

Germ cell tumors (GCTs) arising in infants, children, and adolescents present a set of special challenges. GCTs make up about 3% of malignancies in children aged 0–18 and nearly 15% of cancers in adolescents. Epidemiologic and molecular evidence suggests that GCTs in young children likely represent a distinct biologic group as compared to GCTs of older adolescents and adults. Despite this difference, pediatric GCTs are typically treated with cisplatin-based multiagent regimens similar to those used in adults. There is evidence that children are particularly vulnerable to late effects of conventional therapy, including ototoxicity, pulmonary abnormalities, and secondary malignancies, motivating the search for molecular targets for novel therapies. Evidence is accumulating that the genes and mechanisms controlling normal germ cell development are particularly relevant to the understanding of germ cell tumorigenesis. Perturbations in the epigenetic program of germ cell differentiation, with resulting effects on the regulation of pluripotency, may contribute to the marked histologic variability of GCTs. Perturbations in the KIT receptor signaling pathway have been identified via next-generation sequencing studies and in genome-wide association studies of testicular cancer susceptibility. Here, we review these and other biological insights that may fuel further translational and clinical research in childhood GCTs.

Fatal haemorrhage and neoplastic thrombosis in a captive African lion (Panthera leo) with metastatic testicular sex cord-stromal tumour

BACKGROUND

The study of neoplasia in wildlife species contributes to the understanding of cancer biology, management practices, and comparative pathology. Higher frequencies of neoplasms among captive non-domestic felids have been reported most commonly in aging individuals. However, testicular tumours have rarely been reported. This report describes a metastatic testicular sex cord-stromal tumour leading to fatal haemorrhage and thrombosis in a captive African lion (Panthera leo).

CASE PRESENTATION

During necropsy of a 16-year-old male African lion, the left testicle and spermatic cord were found to be intra-abdominal (cryptorchid), semi-hard and grossly enlarged with multiple pale-yellow masses. Encapsulated haemorrhage was present in the retroperitoneum around the kidneys. Neoplastic thrombosis was found at the renal veins opening into the caudal vena cava. Metastases were observed in the lungs and mediastinal lymph nodes. Histology revealed a poorly differentiated pleomorphic neoplasm comprised of round to polygonal cells and scattered spindle cells with eosinophilic cytoplasm. An immunohistochemistry panel of inhibin-α, Ki-67, human placental alkaline phosphatase, cytokeratin AE1/AE3, cKit, vimentin and S100 was conducted. Positive cytoplasmic immunolabeling was obtained for vimentin and S100.

CONCLUSIONS

The gross, microscopic and immunohistochemical findings of the neoplasm were compatible with a poorly differentiated pleomorphic sex cord-stromal tumour. Cause of death was hypovolemic shock from extensive retroperitoneal haemorrhage and neoplastic thrombosis may have contributed to the fatal outcome. To our knowledge, this is the first report of sex cord-stromal tumour in non-domestic felids.

Frequency and Markers of Precursor Lesions and Implications for the Pathogenesis of Testicular Germ Cell Tumors

BACKGROUND

The World Health Organization classification of urologic cancer 2016 describes 3 noninvasive precursor lesions for testicular germ cell tumor type II (TGCT) of young adults. Germ cell neoplasia in situ is the initial precursor lesion. Intratubular seminoma (ITSE), and intratubular embryonal carcinoma (ITEC) are 2 intermediate precursor lesions. Microinvasive testicular germ cell tumor (MGCT) is an invasive precursor lesion.

MATERIALS AND METHODS

We undertook a retrospective study of testes obtained using orchiectomy for TGCT and examined precursor lesions. The examinations included immunohistochemical staining of the precursor lesions for octamer-binding transcription factor 4 (OCT4), CD117, and CD30. We examined 63 consecutive and evaluable patients.

RESULTS

Of the patients, 44 had seminoma and 19 had a nonseminomatous TGCT. MGCT was more frequent than ITSE (P = .002; χ2 test). None of the testes had ITEC. Immunohistochemistry showed that 72 of 77 precursor lesions (93%) stained positive for OCT4 and CD117 and negative for CD30. The pattern represents a seminomatous immunophenotype. A meta-analysis of the published studies regarding precursor lesions included 1007 patients. Overall, the pooled rate of ITSE was 29% (95% confidence interval [CI], 18%-40%) and the pooled rate of MGCT was 21% (95% CI, 15%-27%).

CONCLUSION

MGCT is a frequent intermediate precursor lesion.

Precursor Lesions of Urologic Malignancies

CONTEXT

- Precursor lesions of urologic malignancies are established histopathologic entities, which are important not only to recognize for clinical purposes, but also to further investigate at the molecular level in order to gain a better understanding of the pathogenesis of these malignancies.

OBJECTIVE

- To provide a brief overview of precursor lesions to the most common malignancies that develop within the genitourinary tract with a focus on their clinical implications, histologic features, and molecular characteristics.

DATA SOURCES

- Literature review from PubMed, urologic pathology textbooks, and the 4th edition of the World Health Organization Classification of Tumours of the Urinary System and Male Genital Organs. All photomicrographs were taken from cases seen at Weill Cornell Medicine or from the authors' personal slide collections.

CONCLUSIONS

- The clinical importance and histologic criteria are well established for the known precursor lesions of the most common malignancies throughout the genitourinary tract, but further investigation is warranted at the molecular level to better understand the pathogenesis of these lesions. Such investigation may lead to better risk stratification of patients and potentially novel treatments.

Primordial germ cell differentiation of nuclear transfer embryonic stem cells using surface modified electroconductive scaffolds

A combination of nanotopographical cues and surface modification of collagen and fibronectin is a potential platform in primordial germ cells (PGCs) differentiation. In the present study, the synergistic effect of nanotopography and surface modification on differentiation of nuclear transfer embryonic stem cells (nt-ESCs) toward PGC lineage was investigated. In order to achieve this goal, poly-anyline (PANi) was mix within poly-L-lactic acid (PLLA). Afterward, the random composite mats were fabricated using PLLA and PANi mix solution. The nanofiber topography notably upregulated the expressions of prdm14, mvh and c-kit compared with tissue culture polystyrene (TCP). Moreover, the combination of nanofiber topography and surface modification resulted in more enhancement of PGCs differentiation compared with non-modified nanofibrous scaffold. Additionally, gene expression results showed that mvh and c-kit were expressed at higher intensity in cells exposed to collagen and fibronectin rather than collagen or fibronectin solitary. These results demonstrated the importance of combined effect of collagen and fibronectin in order to develop a functional extracellular matrix (ECM) mimic in directing stem cell fate and the potential of such biofunctional scaffolds for treatment of infertility.

Gonadal dysgenesis in disorders of sex development: Diagnosis and surgical management

Recent studies on gonadal histology have improved the understanding of germ cell malignancy risk in patients with disorders of sex development (DSD), and evidence-based gonadal management strategies are gradually emerging. Especially in 46,XY DSD and 45,X/46,XY DSD, which are characterized by gonadal dysgenesis, the risk of germ cell malignancy is significantly increased. This paper summarized the progress over the past 10 years in malignancy risk assessment in patients with DSD, and its implications for optimal surgical handling of the involved gonads.

The biology of germ cell tumors in disorders of sex development

Development of a malignant germ cell tumor, i.e., germ cell cancer (GCC) in individuals with disorders of sex development (DSD) depends on a number of (epi-)genetic factors related to early gonadal- and germ cell development, possibly related to genetic susceptibility. Fetal development of germ cells is orchestrated by strict processes involving specification, migration and the development of a proper gonadal niche. In this review we will discuss the early (epi-)genetic events in normal and aberrant germ cell and gonadal development. Focus will be on the formation of the precursor lesions of GCC in individuals who have DSD. In our view, expression of the different embryonic markers in, and epigenetic profile of the precursor lesions reflects the developmental stage in which these cells are blocked in their maturation. Therefore, these are not a primary pathogenetic driving force. Progression later in life towards a full blown cancer likely depends on additional factors such as a changed endocrine environment in a susceptible individual. Genetic susceptibility is, as evidenced by the presence of specific risk genetic variants (SNPs) in patients with a testicular GCC, related to genes involved in early germ cell and gonadal development.

Spermatogonial Nature of the Germ Cell Component of Canine Testicular Mixed Germ Cell-Sex Cord Stromal Tumours

The present study has characterized the germ cell component of canine testicular mixed germ cell-sex cord stromal tumours (MGSCTs) by examining the histological nature and histochemical and immunohistochemical features using gonocytic and spermatogonial cellular markers, c-Kit, placental alkaline phosphatase (PLAP), protein gene product 9.5 (PGP9.5), Sal-like protein 4 (SALL4), and the periodic acid-Schiff (PAS) reaction. Histologically, all 45 examples of MGSCTs were classified as spermatocytic seminomas (SSs) and Sertoli cell tumours in combination. The germ cell component of all MGSCTs was negative by PAS staining. Immunohistochemically, PLAP immunoreactivity was lacking in the germ cell component of all MGSCTs, which is not consistent with a gonocytic origin. The germ cell component was positive for PGP9.5 and SALL4 in all MGSCTs and positive for c-Kit in 53% of MGSCTs, which is consistent with the phenotype of spermatogonia. Furthermore, the germ cell component in 71% of MGSCTs had moderate immunoreactivity for SALL4, which is suggestive of a spermatogonial phenotype. Conversely, 29% of cases had a minor population of germ cells showing strong SALL4 immunoreactivity, suggesting a phenotype similar to prespermatogonia. The results suggest that the germ cell component of canine MGSCTs is morphologically classified as SS, with the majority of cases showing the spermatogonial phenotype and some cases containing a small population of prespermatogonia.

The 2016 WHO Classification of Tumours of the Urinary System and Male Genital Organs-Part A: Renal, Penile, and Testicular Tumours

The fourth edition of the World Health Organization (WHO) classification of urogenital tumours (WHO "blue book"), published in 2016, contains significant revisions. These revisions were performed after consideration by a large international group of pathologists with special expertise in this area. A subgroup of these persons met at the WHO Consensus Conference in Zurich, Switzerland, in 2015 to finalize the revisions. This review summarizes the most significant differences between the newly published classification and the prior version for renal, penile, and testicular tumours. Newly recognized epithelial renal tumours are hereditary leiomyomatosis and renal cell carcinoma (RCC) syndrome-associated RCC, succinate dehydrogenase-deficient RCC, tubulocystic RCC, acquired cystic disease-associated RCC, and clear cell papillary RCC. The WHO/International Society of Urological Pathology renal tumour grading system was recommended, and the definition of renal papillary adenoma was modified. The new WHO classification of penile squamous cell carcinomas is based on the presence of human papillomavirus and defines histologic subtypes accordingly. Germ cell neoplasia in situ (GCNIS) of the testis is the WHO-recommended term for precursor lesions of invasive germ cell tumours, and testicular germ cell tumours are now separated into two fundamentally different groups: those derived from GCNIS and those unrelated to GCNIS. Spermatocytic seminoma has been designated as a spermatocytic tumour and placed within the group of non-GCNIS-related tumours in the 2016 WHO classification.

PATIENT SUMMARY

The 2016 World Health Organization (WHO) classification contains new renal tumour entities. The classification of penile squamous cell carcinomas is based on the presence of human papillomavirus. Germ cell neoplasia in situ of the testis is the WHO-recommended term for precursor lesions of invasive germ cell tumours.

Male Reproductive Disorders and Fertility Trends: Influences of Environment and Genetic Susceptibility

It is predicted that Japan and European Union will soon experience appreciable decreases in their populations due to persistently low total fertility rates (TFR) below replacement level (2.1 child per woman). In the United States, where TFR has also declined, there are ethnic differences. Caucasians have rates below replacement, while TFRs among African-Americans and Hispanics are higher. We review possible links between TFR and trends in a range of male reproductive problems, including testicular cancer, disorders of sex development, cryptorchidism, hypospadias, low testosterone levels, poor semen quality, childlessness, changed sex ratio, and increasing demand for assisted reproductive techniques. We present evidence that several adult male reproductive problems arise in utero and are signs of testicular dysgenesis syndrome (TDS). Although TDS might result from genetic mutations, recent evidence suggests that it most often is related to environmental exposures of the fetal testis. However, environmental factors can also affect the adult endocrine system. Based on our review of genetic and environmental factors, we conclude that environmental exposures arising from modern lifestyle, rather than genetics, are the most important factors in the observed trends. These environmental factors might act either directly or via epigenetic mechanisms. In the latter case, the effects of exposures might have an impact for several generations post-exposure. In conclusion, there is an urgent need to prioritize research in reproductive physiology and pathophysiology, particularly in highly industrialized countries facing decreasing populations. We highlight a number of topics that need attention by researchers in human physiology, pathophysiology, environmental health sciences, and demography.

Cross platform analysis of methylation, miRNA and stem cell gene expression data in germ cell tumors highlights characteristic differences by tumor histology

Background

Alterations in methylation patterns, miRNA expression, and stem cell protein expression occur in germ cell tumors (GCTs). Our goal is to integrate molecular data across platforms to identify molecular signatures in the three main histologic subtypes of Type I and Type II GCTs (yolk sac tumor (YST), germinoma, and teratoma).

Methods

We included 39 GCTs and 7 paired adjacent tissue samples in the current analysis. Molecular data available for analysis include DNA methylation data (Illumina GoldenGate Cancer Methylation Panel I), miRNA expression (NanoString nCounter miRNA platform), and stem cell factor expression (SABiosciences Human Embryonic Stem Cell Array). We evaluated the cross platform correlations of the data features using the Maximum Information Coefficient (MIC).

Results

In analyses of individual datasets, differences were observed by tumor histology. Germinomas had higher expression of transcription factors maintaining stemness, while YSTs had higher expression of cytokines, endoderm and endothelial markers. We also observed differences in miRNA expression, with miR-371-5p, miR-122, miR-302a, miR-302d, and miR-373 showing elevated expression in one or more histologic subtypes. Using the MIC, we identified correlations across the data features, including six major hubs with higher expression in YST (LEFTY1, LEFTY2, miR302b, miR302a, miR 126, and miR 122) compared with other GCT.

Conclusions

While prognosis for GCTs is overall favorable, many patients experience resistance to chemotherapy, relapse and/or long term adverse health effects following treatment. Targeted therapies, based on integrated analyses of molecular tumor data such as that presented here, may provide a way to secure high cure rates while reducing unintended health consequences.

Analysis of POU5F1, c-Kit, PLAP, AP2γ and SALL4 in gonocytes of patients with cryptorchidism

Cryptorchidism is a risk factor for the development of testicular germ cell tumors (TGCTs). The most common type of TGCT in cryptorchidism is seminoma. The intratubular germ cell neoplasia unclassified (ITGCNU) is a histological pattern preceding the development of seminomas and non-seminomas. It was suggested that in patients with cryptorchidism, the gonocytes remained undifferentiated with pluripotent abilities expressing proteins like POU domain class 5 transcription factor 1 (POU5F1), tyrosine kinase receptor c-Kit, placental-like alkaline phosphatase (PLAP), the transcription factor AP2γ and sal-like protein 4 (SALL4) that confer to the gonocytes this ability and therefore make them susceptible to develop ITGCNU. The aim of the present study was to determine if the gonocytes of patients with cryptorchidism express POU5F1, c-Kit, PLAP, AP2γ and SALL4 proteins after their differentiation period. Based on this, we evaluated samples of testicular tissue from newborns to 16-year old subjects with or without cryptorchidism in search of POU5F1, c-Kit, PLAP, AP2γ and SALL4 using immunocytochemical method, the results of which were validated by RT-PCR. The results showed that control subjects witnessed a down-regulation in the expression of these five proteins in the first year of life, which eventually disappeared. On the other hand, it was determined that 21.6% (8/37) of the patients with cryptorchidism continued to express, at least, one of the proteins analyzed in this study after the second year of life. And only 5.4% (2/37) of the patients were positive to the five markers. These data sustain the proposed hypothesis that in cryptorchid patients, ITGCNU arises from gonocytes that fail in their differentiation process to spermatogonia with conservation of the proteins (POU5F1, c-Kit, PLAP, AP2γ and SALL4) that maintain pluripotency and undifferentiated characteristics and which are responsible for making the gonocytes susceptible to malignancy. However, we cannot guarantee that these patients present neoplastic transformation.

Pathogenesis of germ cell neoplasia in testicular dysgenesis and disorders of sex development

Development of human gonads is a sex-dimorphic process which evolved to produce sex-specific types of germ cells. The process of gonadal sex differentiation is directed by the action of the somatic cells and ultimately results in germ cells differentiating to become functional gametes through spermatogenesis or oogenesis. This tightly controlled process depends on the proper sequential expression of many genes and signalling pathways. Disturbances of this process can be manifested as a large spectrum of disorders, ranging from severe disorders of sex development (DSD) to - in the genetic male - mild reproductive problems within the testicular dysgenesis syndrome (TDS), with large overlap between the syndromes. These disorders carry an increased but variable risk of germ cell neoplasia. In this review, we discuss the pathogenesis of germ cell neoplasia associated with gonadal dysgenesis, especially in individuals with 46,XY DSD. We summarise knowledge concerning development and sex differentiation of human gonads, with focus on sex-dimorphic steps of germ cell maturation, including meiosis. We also briefly outline the histopathology of germ cell neoplasia in situ (GCNIS) and gonadoblastoma (GDB), which are essentially the same precursor lesion but with different morphological structure dependent upon the masculinisation of the somatic niche. To assess the risk of germ cell neoplasia in different types of DSD, we have performed a PubMed search and provide here a synthesis of the evidence from studies published since 2006. We present a model for pathogenesis of GCNIS/GDB in TDS/DSD, with the risk of malignancy determined by the presence of the testis-inducing Y chromosome and the degree of masculinisation. The associations between phenotype and the risk of neoplasia are likely further modulated in each individual by the constellation of the gene polymorphisms and environmental factors.

An oncofetal and developmental perspective on testicular germ cell cancer

Germ cell tumors (GCTs) represent a diverse group of tumors presumably originating from (early fetal) developing germ cells. Most frequent are the testicular germ cell cancers (TGCC). Overall, TGCC is the most frequent malignancy in Caucasian males (20-40 years) and remains an important cause of (treatment related) mortality in these young men. The strong association between the phenotype of TGCC stem cell components and their totipotent ancestor (fetal primordial germ cell or gonocyte) makes these tumors highly relevant from an onco-fetal point of view. This review subsequently discusses the evidence for the early embryonic origin of TGCCs, followed by an overview of the crucial association between TGCC pathogenesis, genetics, environmental exposure and the (fetal) testicular micro-environment (genvironment). This culminates in an evaluation of three genvironmentally modulated hallmarks of TGCC directly related to the oncofetal pathogenesis of TGCC: (1) maintenance of pluripotency, (2) cell cycle control/cisplatin sensitivity and (3) regulation of proliferation/migration/apoptosis by KIT-KITL mediated receptor tyrosine kinase signaling. Briefly, TGCC exhibit identifiable stem cell components (seminoma and embryonal carcinoma) and progenitors that show large and consistent similarities to primordial/embryonic germ cells, their presumed totipotent cells of origin. TGCC pathogenesis depends crucially on a complex interaction of genetic and (micro-)environmental, i.e. genvironmental risk factors that have only been partly elucidated despite significant effort. TGCC stem cell components also show a high degree of similarity with embryonic stem/germ cells (ES) in the regulation of pluripotency and cell cycle control, directly related to their exquisite sensitivity to DNA damaging agents (e.g. cisplatin). Of note, (ES specific) micro-RNAs play a pivotal role in the crossover between cell cycle control, pluripotency and chemosensitivity. Moreover, multiple consistent observations reported TGCC to be associated with KIT-KITL mediated receptor tyrosine kinase signaling, a pathway crucially implicated in proliferation, migration and survival during embryogenesis including germ cell development. In conclusion, TGCCs are a fascinating model for onco-fetal developmental processes especially with regard to studying cell cycle control, pluripotency maintenance and KIT-KITL signaling. The knowledge presented here contributes to better understanding of the molecular characteristics of TGCC pathogenesis, translating to identification of at risk individuals and enhanced quality of care for TGCC patients (diagnosis, treatment and follow-up).

Complete androgen insensitivity syndrome: factors influencing gonadal histology including germ cell pathology

Patients with complete androgen insensitivity syndrome are at an increased risk for the development of gonadal germ cell cancer. Residual androgen receptor (AR) activity and abnormal gonadal location may influence the survival of atypical germ cells and the development of other histopathological features. To assess this, we evaluated 37 gonads from 19 patients with complete androgen insensitivity (ranging in age from 3 months to 18 years). Histological abnormalities were examined using hematoxylin and eosin-stained sections and sections stained for POU5F1 and KITLG, markers of early changes in germ cells at risk for malignant transformation. Hamartomatous nodules (HNs), Leydig cell hyperplasia (LCH), decreased germ cells, tubular atrophy and stromal fibrosis were more pronounced as age increased (P<0.001). Expected residual AR activity acted as a positive predictor only for non-malignant germ cell survival in (post)pubertal patients (P<0.05). Immunohistochemical studies indicated that delayed maturation of germ cells was present in three patients, whereas intermediate changes that occurred between delayed maturation and intratubular germ cell neoplasia, designated pre-intratubular germ cell neoplasia, were identified in four cases. Intratubular germ cell neoplasia was observed in one patient. Neither POU5F1 nor KITLG expression was dependent on expected residual AR activity. An independent effect of inguinal versus abdominal position of the gonads was difficult to assess because inguinal gonads were present primarily in the youngest individuals. In conclusion, many histological changes occur increasingly with age. Expected residual AR activity contributes to better survival of the general germ cell population in (post)pubertal age; however, it did not seem to have an important role in the survival of the germ cells at risk for malignant transformation (defined by POU5F1 positivity and KITLG overexpression) in complete androgen insensitivity. Comparison of the high percentage of patients in our study that were carrying germ cells with delayed maturation or pre-intratubular germ cell neoplasia with previously reported cumulative risk of tumor development in adult patients indicates that not all such precursor lesions in complete androgen insensitivity will progress to invasive germ cell cancer.

Expression of protein gene product 9.5 and Sal-like protein 4 in canine seminomas

The aim of the present study was to characterize canine classical seminoma (SE) and spermatocytic seminoma (SS) by immunohistochemical expression of gonocytic and spermatogonial cellular markers (c-Kit, placental alkaline phosphatase [PLAP], protein gene product 9.5 [PGP9.5] and Sal-like protein 4 [Sall4]) and histochemically by the periodic acid-Schiff (PAS) reaction. Twenty-five cases of SE and 23 cases of SS were investigated. Two cases of dysgerminoma were also examined. c-Kit was expressed on the cell membrane of 13 of 25 cases of SE (52%) and four of 23 cases of SS (16%). This marker was not expressed in dysgerminoma. PLAP immunoreactivity was observed in the cytoplasm of neoplastic cells of six of 25 cases of SE (24%). PLAP was not expressed in cases of SS and dysgerminoma. All samples of SE, SS and dysgerminoma showed cytoplasmic expression of PGP9.5 and nuclear immunoreactivity for Sall4. There was fine granular cytoplasmic PAS staining in neoplastic cells in five of 25 cases of SE (20%), while all samples of SS and dysgerminoma cases were PAS negative. These findings suggest that it is not possible to differentiate canine SE and SS using these markers. This may be because canine SS may be derived from spermatogonia that can differentiate to spermatocytes and also because cases of canine SE might consist of neoplastic cells that have lost their gonocytic nature. This study was the first to show positive immunoreactivity for Sall4 in canine seminomas and dysgerminomas and expression of PGP9.5 in canine dysgerminomas.

45,X/46,X,psu dic(Y) gonadal dysgenesis: influence of the two cell lines on the clinical phenotype, including gonadal histology

A child born with ambiguous genitalia (Prader III) was found to have a 45,X[92.2%]/46,X,psu dic(Y)(p12)[7.8%] karyotype in peripheral blood lymphocytes. The testosterone level was consistent with that of a normal male; however, gonadotropins were elevated. Ultrasound and endoscopy of the urogenital sinus revealed well-developed Müllerian structures. At 3.5 months, the child was operated for right-sided incarcerated hernia, and the gonad situated at the inguinal region was biopsied and classified as primitive testis. Based on the presence of Müllerian structures, anatomy of external genitalia and wish of the parents, the child was assigned female gender. She underwent removal of the left gonad at 4 months during another acute surgery; histology was similar to the right gonad. The rest of the right gonad was removed at 16 months, and feminizing genitoplasty took place at 3 years. The right and left gonad contained 28 and 22% of cells with a Y chromosome, respectively. During further histological examination, dysgenetic features of the gonads were discovered. Some germ cells displayed abnormal development based on the specific expression of immunohistochemical markers (OCT3/4, TSPY, KITLG), indicating a possible risk for future malignant germ cell tumor development. Contribution of the 45,X cell line to the phenotype was also observed: the patient developed celiac disease, and her growth pattern resembled that of Turner syndrome responding to growth hormone treatment.

Raman microspectroscopic discrimination of TCam-2 cultures reveals the presence of two sub-populations of cells

TCam-2 cells are the main in vitro model for investigations into seminomatous tumors. However, despite their widespread use, questions remain regarding the cells' homogeneity and consequently how representative they are of seminomas. We assess the TCam-2 cell line using routine and novel authentication methods to determine its homogeneity, identify any cellular sub-populations and resolve whether any changes could be due to generational differentiation. TCam-2, embryonal carcinoma cells (2102EP) and breast cancer cell (MCF7) lines were assessed using qRT-PCR, immunocytochemistry, flow cytometry and short tandem repeat analyses. Raman maps of individual cells (minimum of 10) and single scan spectra from 200 cells per culture were obtained. TCam-2s displayed the characteristic marker gene expression pattern for seminoma, were uniform in size and granularity and short tandem repeat analysis showed no contamination. However, based only on physical parameters, flowcytometry was unable to differentiate between TCam-2 and 2102EPs. Raman maps of TCam-2s comprised three equally distributed, distinct spectral patterns displaying large intercellular single spectral variation. All other cells showed little variation. Principal component, cluster and local spectral angle analyses indicated that the TCam-2s contained two different types of cells, one of which comprised two subgroups and was similar to some 2102EP cells. Protein expression corroborated the presence of different cells and generational differences. The detailed characterization provided by the Raman spectra, augmented by the routine methods, provide substantiation to the long-held suspicion that TCam-2 are not homogeneous but comprise differing cell populations, one of which may be embryonal carcinoma in origin.