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1.
Br J Surg ; 107(13): 1791-1800, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32757307

RESUMO

BACKGROUND: Active surveillance has been proposed for patients with oesophageal cancer in whom there is a complete clinical response after neoadjuvant chemoradiotherapy (nCRT). However, endoscopic biopsies have limited negative predictive value in detecting residual disease. This study determined the location of residual tumour following surgery to improve surveillance and endoscopic strategies. METHODS: The present study was based on patients who participated in the prospective preSANO trial with adenocarcinoma or squamous cell carcinoma of the oesophagus or oesophagogastric junction treated in four Dutch hospitals between 2013 and 2016. Resection specimens and endoscopic biopsies taken during clinical response evaluations after nCRT were reviewed by two expert gastrointestinal pathologists. The exact location of residual disease in the oesophageal wall was determined in resection specimens. Endoscopic biopsies were assessed for the presence of structures representing the submucosal layer of the oesophageal wall. RESULTS: In total, 119 eligible patients underwent clinical response evaluations after nCRT followed by standard surgery. Residual tumour was present in endoscopic biopsies from 70 patients, confirmed on histological analysis of the resected organ. Residual tumour was present in the resection specimen from 27 of the other 49 patients, despite endoscopic biopsies being negative. Of these 27 patients, residual tumour was located in the mucosa in 18, and in the submucosa beneath tumour-free mucosa in eight. One patient had tumour in muscle beneath tumour-free mucosa and submucosa. CONCLUSION: Most residual disease after nCRT missed by endoscopic biopsies was located in the mucosa. Active surveillance could be improved by more sampling and considering submucosal biopsies.


ANTECEDENTES: Se ha propuesto un seguimiento activo para los pacientes con cáncer de esófago en los que se logra una respuesta clínica completa tras quimiorradioterapia neoadyuvante (neoadjuvant chemoradiotherapy, nCRT). Sin embargo, las biopsias endoscópicas tienen un valor predictivo limitado para detectar la enfermedad residual. En este estudio se evaluó la localización del tumor residual tras la cirugía para poder determinar estrategias de seguimiento y endoscópicas. MÉTODOS: Este estudio se basa en pacientes que participaron en el ensayo prospectivo preSANO (adenocarcinoma o carcinoma escamoso del esófago o unión esofagogástrica en cuatro hospitales de los Países Bajos entre 2013 y 2016). Los especímenes quirúrgicos, así como las biopsias endoscópicas efectuadas durante las evaluaciones de la respuesta clínica después de nCRT fueron revisadas por dos patólogos gastrointestinales expertos. En los especímenes de resección, se determinó la localización exacta de la enfermedad residual en la pared del esófago. Se evaluaron las biopsias endoscópicas para identificar estructuras que constituyeran la capa submucosa de la pared del esófago. RESULTADOS: En total, 119 pacientes elegibles fueron sometidos a evaluaciones de la respuesta clínica tras nCRT seguida de cirugía estándar. Se detectó tumor residual en las biopsias endoscópicas de 70 pacientes, luego confirmadas en la histología de la pieza extirpada. Se identificó tumor residual en la pieza de resección de 27 de los otros 49 pacientes, a pesar de que las biopsias endoscópicas fueron negativas. En estos 27 pacientes, 18 presentaban tumor residual en la mucosa y ocho pacientes en la submucosa mas allá de una mucosa libre de tumor. Un paciente tenía tumor en el músculo más allá de una mucosa y submucosa libres de tumor. CONCLUSIÓN: La mayoría de los casos de enfermedad residual tras nCRT que no se detectaron en las biopsias endoscópicas, se localizaban en la mucosa. El seguimiento activo podría mejorar con la toma de más muestras y considerando las biopsias submucosas.


Assuntos
Adenocarcinoma/terapia , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia Adjuvante , Mucosa Esofágica/patologia , Neoplasias Esofágicas/terapia , Esofagoscopia , Terapia Neoadjuvante , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Assistência ao Convalescente , Idoso , Biópsia , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Mucosa Esofágica/diagnóstico por imagem , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Valor Preditivo dos Testes , Estudos Prospectivos
2.
BMC Cancer ; 19(1): 1124, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31744479

RESUMO

BACKGROUND: Testicular germ cell cancer (TGCC) develops from pre-malignant germ neoplasia in situ (GCNIS) cells. GCNIS originates from fetal gonocytes (POU5F1+/MAGE-A4-), which fail to differentiate to pre-spermatogonia (POU5F1-/MAGE-A4+) and undergo malignant transformation. Gankyrin is an oncogene which has been shown to prevent POU5F1 degradation and specifically interact with MAGE-A4 in hepatocellular carcinoma (HCC) cells. We aimed to investigate the role of Gankyrin in progression from gonocyte to pre-invasive GCNIS and subsequent invasive TGCC. METHODS: We determined Gankyrin expression in human fetal testicular tissue (gestational weeks 9-20; n = 38), human adult testicular tissue with active spermatogenesis (n = 9), human testicular tissue with germ cell maturation delay (n = 4), testicular tissue from patients with pre-invasive GCNIS (n = 6), and invasive TGCC including seminoma (n = 6) and teratoma (n = 7). Functional analysis was performed in-vitro by siRNA knock-down of Gankyrin in the NTera2 cells (derived from embryonal carcinoma). RESULTS: Germ cell expression of Gankyrin was restricted to a sub-population of prespermatogonia in human fetal testes. Nuclear Gankyrin was also expressed in GCNIS cells of childhood and adult pre-invasive TGCC patients, and in GCNIS from seminoma and non-seminoma patients. Cytoplasmic expression was observed in seminoma tumour cells and NTera2 cells. Gankyrin knock-down in NTera2 cells resulted in an increase in apoptosis mediated via the TP53 pathway, whilst POU5F1 expression was unaffected. Furthermore, Gankyrin knock-down in NTera2 cells increased cisplatin sensitivity with an increase in cell death (13%, p < 0.05) following Gankyrin knock-down, when compared to cisplatin treatment alone, likely via BAX and FAS. Our results demonstrate that Gankyrin expression changes in germ cells during normal transition from gonocyte to prespermatogonia. In addition, changes in Gankyrin localisation are associated with progression of pre-invasive GCNIS to invasive TGCC. Furthermore, we found that Gankyrin is involved in the regulation of NTera2 cell survival and that a reduction in Gankyrin expression can modulate cisplatin sensitivity. CONCLUSIONS: These results suggest that manipulation of Gankyrin expression may reduce the cisplatin dose required for the treatment of TGCC, with benefits in reducing dose-dependent side effects of chemotherapy. Further studies are required in order to assess the effects of modulating Gankyrin on GCNIS/TGCC using in vivo models.


Assuntos
Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Embrionárias de Células Germinativas/genética , Oncogenes , Complexo de Endopeptidases do Proteassoma/genética , Proteínas Proto-Oncogênicas/genética , Neoplasias Testiculares/genética , Apoptose/genética , Biomarcadores Tumorais , Ciclo Celular/genética , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Humanos , Imuno-Histoquímica , Masculino
3.
Hum Reprod ; 32(12): 2561-2573, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29121256

RESUMO

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.


Assuntos
Síndrome de Resistência a Andrógenos/diagnóstico , Síndrome de Resistência a Andrógenos/genética , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Neoplasias Embrionárias de Células Germinativas/genética , Polimorfismo de Nucleotídeo Único , Neoplasias Testiculares/diagnóstico , Neoplasias Testiculares/genética , Adolescente , Adulto , Alelos , Síndrome de Resistência a Andrógenos/complicações , Síndrome de Resistência a Andrógenos/epidemiologia , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Embrionárias de Células Germinativas/complicações , Neoplasias Embrionárias de Células Germinativas/epidemiologia , Fenótipo , Prevalência , Maturidade Sexual , Fator de Células-Tronco/genética , Neoplasias Testiculares/complicações , Neoplasias Testiculares/epidemiologia , Adulto Jovem
4.
Br J Surg ; 104(10): 1327-1337, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28692180

RESUMO

BACKGROUND: Oesophageal adenocarcinoma (OAC) is a highly aggressive malignancy with poor survival, which is highly variable amongst patients with comparable conventional prognosticators. Therefore molecular biomarkers are urgently needed to improve the prediction of survival in these patients. SRY (sex determining region Y)-box 2, also known as SOX2, is a transcription factor involved in embryonal development of the gastrointestinal tract as well as in carcinogenesis. The purpose of this study was to see whether SOX2 expression is associated with survival in patients with OAC. METHODS: SOX2 was studied by immunohistochemistry in patients who had undergone potentially curative oesophagectomy for adenocarcinoma. Protein expression of SOX2 was evaluated using tissue microarrays from resection specimens, and results were analysed in relation to the clinical data by Cox regression analysis. SOX2 was evaluated in two independent OAC cohorts (Rotterdam cohort and a multicentre UK cohort). RESULTS: Loss of SOX2 expression was independently predictive of adverse overall survival in the multivariable analysis, adjusted for known factors influencing survival, in both cohorts (Rotterdam cohort: hazard ratio (HR) 1·42, 95 per cent c.i. 1·07 to 1·89, P = 0·016; UK cohort: HR 1·54, 1·08 to 2·19, P = 0·017). When combined with clinicopathological staging, loss of SOX2 showed an increased effect in patients with pT1-2 tumours (P = 0·010) and node-negative OAC (P = 0·038), with an incrementally adverse effect on overall survival for stage I OAC with SOX2 loss (HR 3·18, 1·18 to 8·56; P = 0·022). CONCLUSION: SOX2 is an independent prognostic factor for long-term survival in OAC, especially in patients with stage I OAC.


Assuntos
Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/mortalidade , Expressão Gênica , Fatores de Transcrição SOXB1/genética , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Esofagectomia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico
5.
J Urol ; 193(1): 291-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25109686

RESUMO

PURPOSE: Boys with Prader-Willi syndrome often have undescended testes. Prospective studies on the treatment of cryptorchidism in these patients are lacking. We evaluated the effects of human chorionic gonadotropin administration on testis position in 16 males with Prader-Willi syndrome. In patients who subsequently underwent orchiopexy biopsy was taken and testis histology was evaluated. MATERIALS AND METHODS: A total of 16 boys (median age 1.6 years, IQR 1.2 to 1.8) with Prader-Willi syndrome and cryptorchidism underwent human chorionic gonadotropin stimulation test. After a positive test human chorionic gonadotropin treatment was initiated. Patients received 250 to 500 IU (depending on age) intramuscularly twice weekly for 6 weeks. RESULTS: We found 1 testis in a stable scrotal position, 1 vanished testis and 1 atrophic abdominal testis. Of 29 testes responding to human chorionic gonadotropin 23% reached a stable scrotal position, 62% reached a lower position and 14% did not change position. Thus, 22 testes required orchiopexy. Of 17 obtained biopsies in 12 patients 2 showed germ cells in more than 60% of seminiferous tubules, 3 in 30% to 60% and 7 in less than 30%. In addition, 4 boys had Sertoli cell only syndrome and 1 had a vanished testis. In patients undergoing orchiopexy younger age and increased inhibin B and testosterone levels after human chorionic gonadotropin stimulation were associated with a greater number of germ cell containing tubules. CONCLUSIONS: Human chorionic gonadotropin administration resulted in an anatomically lower testis position in most of our patients with Prader-Willi syndrome, and 23% of testes reached a stable scrotal position. Of the cases 76% required orchiopexy to ensure a stable position in the scrotum.


Assuntos
Gonadotropina Coriônica/uso terapêutico , Criptorquidismo/patologia , Criptorquidismo/terapia , Síndrome de Prader-Willi/complicações , Criptorquidismo/etiologia , Humanos , Lactente , Masculino , Procedimentos Cirúrgicos Urológicos Masculinos
6.
Ann Oncol ; 24(4): 878-88, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23152360

RESUMO

In November 2011, the Third European Consensus Conference on Diagnosis and Treatment of Germ-Cell Cancer (GCC) was held in Berlin, Germany. This third conference followed similar meetings in 2003 (Essen, Germany) and 2006 (Amsterdam, The Netherlands) [Schmoll H-J, Souchon R, Krege S et al. European consensus on diagnosis and treatment of germ-cell cancer: a report of the European Germ-Cell Cancer Consensus Group (EGCCCG). Ann Oncol 2004; 15: 1377-1399; Krege S, Beyer J, Souchon R et al. European consensus conference on diagnosis and treatment of germ-cell cancer: a report of the second meeting of the European Germ-Cell Cancer Consensus group (EGCCCG): part I. Eur Urol 2008; 53: 478-496; Krege S, Beyer J, Souchon R et al. European consensus conference on diagnosis and treatment of germ-cell cancer: a report of the second meeting of the European Germ-Cell Cancer Consensus group (EGCCCG): part II. Eur Urol 2008; 53: 497-513]. A panel of 56 of 60 invited GCC experts from all across Europe discussed all aspects on diagnosis and treatment of GCC, with a particular focus on acute and late toxic effects as well as on survivorship issues. The panel consisted of oncologists, urologic surgeons, radiooncologists, pathologists and basic scientists, who are all actively involved in care of GCC patients. Panelists were chosen based on the publication activity in recent years. Before the meeting, panelists were asked to review the literature published since 2006 in 20 major areas concerning all aspects of diagnosis, treatment and follow-up of GCC patients, and to prepare an updated version of the previous recommendations to be discussed at the conference. In addition, ∼50 E-vote questions were drafted and presented at the conference to address the most controversial areas for a poll of expert opinions. Here, we present the main recommendations and controversies of this meeting. The votes of the panelists are added as online supplements.


Assuntos
Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Embrionárias de Células Germinativas/terapia , Europa (Continente) , Seguimentos , Humanos , Metástase Neoplásica , Estadiamento de Neoplasias , Neoplasias Embrionárias de Células Germinativas/classificação , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Taxa de Sobrevida
7.
Br J Cancer ; 106(2): 414-23, 2012 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-22068818

RESUMO

BACKGROUND: It remains important to understand the biology and identify biomarkers for less studied cancers like testicular cancer. The purpose of this study was to determine the methylation frequency of several cancer-related genes in different histological types of testicular cancer and normal testis tissues (NT). METHODS: DNA was isolated from 43 seminomas (SEs), 14 non-SEs (NSEs) and 23 NT, and was assayed for promoter methylation status of 15 genes by quantitative methylation-specific PCR. The methylation status was evaluated for an association with cancer, and between SEs and NSEs. RESULTS: We found differential methylation pattern in SEs and NSEs. MGMT, VGF, ER-ß and FKBP4 were predominately methylated in NSEs compared with SEs. APC and hMLH1 are shown to be significantly more methylated in both subtypes in comparison with NT. When combining APC, hMLH1, ER-ß and FKBP4, it is possible to identify 86% of the NSEs, whereas only 7% of the SEs. CONCLUSIONS: Our results indicate that the methylation profile of cancer-associated genes in testicular cancer correlates with histological types and show cancer-specific pattern for certain genes. Further methylation analysis, in a larger cohort is needed to elucidate their role in testicular cancer development and potential for therapy, early detection and disease monitoring.


Assuntos
Metilação de DNA , Epigênese Genética , Heterogeneidade Genética , Seminoma/genética , Neoplasias Testiculares/genética , Adulto , Estudos de Coortes , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas
8.
Br J Cancer ; 105(6): 854-63, 2011 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-21847120

RESUMO

BACKGROUND: OCT3/4 (POU5F1) is an established diagnostic immunohistochemical marker for specific histological variants of human malignant germ cell tumours (GCTs), including the seminomatous types and the stem cell component of non-seminomas, known as embryonal carcinoma. OCT3/4 is crucial for the regulation of pluripotency and the self-renewal of normal embryonic stem- and germ cells. Detection of expression of this transcription factor is complicated by the existence of multiple pseudogenes and isoforms. Various claims have been made about OCT3/4 expression in non-GCTs, possibly related to using nonspecific detection methods. False-positive findings undermine the applicability of OCT3/4 as a specific diagnostic tool in a clinical setting. In addition, false-positive findings could result in misinterpretation of pluripotency regulation in solid somatic cancers and their stem cells. Of the three identified isoforms--OCT4A, OCT4B and OCT4B1--only OCT4A proved to regulate pluripotency. Up until now, no convincing nuclear OCT4A protein expression has been shown in somatic cancers or tissues. METHODS: This study investigates expression of the various OCT3/4 isoforms in GCTs (both differentiated and undifferentiated) and somatic (non-germ cell) cancers, including representative cell lines and xenografts. RESULTS: Using specific methods, OCT4A and OCT4B1 are shown to be preferentially expressed in undifferentiated GCTs. The OCT4B variant shows no difference in expression between GCTs (either differentiated or undifferentiated) and somatic cancers. In spite of the presence of OCT4A mRNA in somatic cancer-derived cell lines, no OCT3/4 protein is detected. Significant positive correlations between all isoforms of OCT3/4 were identified in both tumours with and without a known stem cell component, possibly indicating synergistic roles of these isoforms. CONCLUSION: This study confirms that OCT4A protein only appears in seminomatous GCTs, embryonal carcinoma and representative cell lines. Furthermore, it emphasises that in order to correctly assess the presence of functional OCT3/4, both isoform specific mRNA and protein detection are required.


Assuntos
Biomarcadores Tumorais/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Carcinoma Embrionário/metabolismo , Linhagem Celular Tumoral , Humanos , Masculino , Neoplasias Embrionárias de Células Germinativas , Fator 3 de Transcrição de Octâmero/genética , Isoformas de Proteínas/metabolismo , Pseudogenes , RNA Mensageiro/metabolismo , Seminoma/metabolismo , Sensibilidade e Especificidade
9.
Int J Androl ; 34(4 Pt 2): e234-51, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21564133

RESUMO

Human type II germ cell tumours (GCTs) originate from an embryonic germ cell, either as a primordial germ cell or gonocyte. This start determines the biological as well as clinical characteristics of this type of cancer, amongst others their totipotency as well as their overall (exceptional) sensitivity to DNA damaging agents. The histology of the precursor lesion, either carcinoma in situ or gonadoblastoma, depends on the level of testicularization (i.e. testis formation) of the gonad. The impact of either intrinsic (genetic) - and environmental factors involved in the pathogenesis is demonstrated by disorders of sex development as well as testicular dysgenesis syndrome as risk factors, including cryptorchidism, hypospadias and disturbed fertility as parameters. This knowledge allows identification of individuals at risk for development of this type of cancer, being a population of interest for screening. Factors known to regulate pluripotency during embryogenesis are proven to be of diagnostic value for type II GCTs, including OCT3/4, even applicable for non-invasive screening. In addition, presence of stem cell factor, also known as KITLG, allows distinction between delayed matured germ cells and the earliest stages of malignant transformation. This is of special interest because of the identified association between development of type II GCTs of the testis and a limited number of single nucleotide polymorphisms, including some likely related to KITL. Transition from the precursor lesion to an invasive cancer is associated with gain of the short arm of chromosome 12, in which multiple genes might be involved, including KRAS2 and possibly NANOG (pseudogenes). While most precursor lesions will progress to an invasive cancer, only a limited number of cancers will develop treatment resistance. Putative explanatory mechanisms are identified, including presence of microsatellite instability, BRAF mutations, apoptosis suppression and p21 sub-cellular localization. It remains to be investigated how these different pathways integrate to each other and how informative they are at the patient-individual level. Further understanding will allow development of more targeted treatment, which will benefit quality of life of these young cancer patients.


Assuntos
Neoplasias Embrionárias de Células Germinativas/metabolismo , Transdução de Sinais , Neoplasias Testiculares/metabolismo , Biomarcadores Tumorais/genética , Carcinoma in Situ/genética , Carcinoma in Situ/terapia , Humanos , Masculino , Neoplasias Embrionárias de Células Germinativas/genética , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Embrionárias de Células Germinativas/terapia , Fatores de Risco , Neoplasias Testiculares/genética , Neoplasias Testiculares/patologia , Neoplasias Testiculares/terapia
10.
Int J Androl ; 34(4 Pt 2): e189-203, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21649665

RESUMO

Malignant germ-cell tumours arise from a neoplastic precursor, the carcinoma in situ, and develop into seminomas and/or non-seminomas (embryonal carcinomas, teratomas, yolk-sac tumours and choriocarcinomas). Based on histological and clinical findings, it has been postulated that seminomas can eventually transform into non-seminomas. Here, we used the cell line TCam-2 as model for seminomas and interrogated their differentiation potential. We demonstrate that TCam-2 cells are able to differentiate into mixed non-seminomatous lineages after supplementing the media with TGF-ß1, EGF and FGF4. On a molecular level, the differentiation is initiated by repression of BMP/SMAD signalling. As a consequence, BLIMP1, a molecule known to inhibit the differentiation of murine primordial germ cells, is down-regulated and differentiation-inhibiting histone modifications are lost. The appearance of multinucleated giant cells and the expression of marker genes indicate that cells differentiate predominantly into extra-embryonic choriocarcinoma-like cells. This is most likely due to the presence of components of the Hippo pathway, TEAD4 and YAP1. These molecules have been described to trigger extra-embryonic fate determination in the murine system. This study supports the model that seminomas indeed have an intrinsic ability to transform into a non-seminoma. In addition, the data suggest that the transformation does not require an additional mutation, but can be triggered by changes in the tumour microenvironment.


Assuntos
Fator de Crescimento Epidérmico/farmacologia , Fator 4 de Crescimento de Fibroblastos/farmacologia , Neoplasias Embrionárias de Células Germinativas/patologia , Seminoma/patologia , Fator de Crescimento Transformador beta1/farmacologia , Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Biomarcadores/metabolismo , Receptores de Proteínas Morfogenéticas Ósseas/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Coriocarcinoma/embriologia , Proteínas de Ligação a DNA/biossíntese , Fator de Crescimento Epidérmico/metabolismo , Fator 4 de Crescimento de Fibroblastos/metabolismo , Células Gigantes , Histonas/metabolismo , Humanos , Masculino , Proteínas Musculares/biossíntese , Reação em Cadeia da Polimerase , Fator 1 de Ligação ao Domínio I Regulador Positivo , Proteínas Repressoras/biossíntese , Proteínas Repressoras/genética , Transdução de Sinais , Proteínas Smad/metabolismo , Fatores de Transcrição de Domínio TEA , Neoplasias Testiculares , Fatores de Transcrição/biossíntese , Fator de Crescimento Transformador beta1/metabolismo , Microambiente Tumoral
11.
Int J Androl ; 34(4 Pt 2): e204-17, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21668453

RESUMO

Germ cell testicular cancer is understood to arise during embryogenesis, based on the persistence of embryonic germ cell markers in carcinoma in situ and seminoma. In this study, we examine the potential of the seminoma-derived TCam-2 cell line to be used as representative in functional analyses of seminoma. We demonstrate expression of several early germ cell markers, including BLIMP1, OCT3/4, AP2γ, NANOG and KIT. Many TGF-beta superfamily receptors and downstream transcription factors are also present in these cells including the normally foetal ACTRIIA receptor, indicating potential responsiveness to TGF-beta superfamily ligands. Treatment with BMP4 or RA induces a significant increase in ACTRIA, ACTRIIA and ACTRIIB transcripts, whereas activin A decreases ACTRIB. BMP4 and RA each support TCam-2 survival and/or proliferation. In addition, despite increased KIT mRNA levels induced by BMP4, RA and activin A, activin A does not improve survival or proliferation. The capacity for BMP4 and retinoic acid to enhance foetal germ cell survival and proliferation/self-renewal has been demonstrated in mice, but not previously tested in humans. This study is the first to demonstrate a functional response in seminoma cells, using a well-characterized cell line, consistent with their foetal germ cell-like identity.


Assuntos
Células Germinativas/efeitos dos fármacos , Seminoma/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Tretinoína/farmacologia , Receptores de Activinas Tipo II/metabolismo , Ativinas/farmacologia , Complexo 2 de Proteínas Adaptadoras/biossíntese , Biomarcadores , Proteína Morfogenética Óssea 4 , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Proteínas de Homeodomínio/biossíntese , Humanos , Ligantes , Masculino , Proteína Homeobox Nanog , Neoplasias Embrionárias de Células Germinativas/genética , Neoplasias Embrionárias de Células Germinativas/metabolismo , Neoplasias Embrionárias de Células Germinativas/patologia , Fator 3 de Transcrição de Octâmero/biossíntese , Fator 1 de Ligação ao Domínio I Regulador Positivo , Proteínas Proto-Oncogênicas c-kit/biossíntese , Proteínas Repressoras/biossíntese , Seminoma/genética , Seminoma/patologia , Transdução de Sinais , Neoplasias Testiculares/genética , Neoplasias Testiculares/metabolismo , Neoplasias Testiculares/patologia
12.
Int J Androl ; 34(4 Pt 2): e14-9; discussion e20, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21790650

RESUMO

Aspects of the biopsy of the testis from the pathologist's point of view are discussed. Direct enzyme-histochemical staining for alkaline phosphatase (dAP) on frozen sections of biopsies taken during operation is a useful diagnostic tool to aid surgeons in testis-sparing surgery. Biopsy of the contralateral testis for the diagnosis of carcinoma in situ (CIS) in patients with a testicular germ cell tumour is not standard of care in most countries because of the high rate of negative biopsies. Based on risk factors for germ cell tumours, i.p. microlithiasis, a patient population is defined in which the rate of CIS in the contralateral biopsy is about 25%. It is reiterated that the diagnosis of CIS in testicular biopsies requires expertise, and should not be carried out without immunohistochemistry for markers for CIS. As OCT3/4 is increasingly used as marker, it is important to be aware that it may be false-negative in biopsies fixed in Bouin's or Stieve's fixative. Preliminary results are presented on a series of biopsies from cryptorchid testes in infants and children allowing the definition of morphological and immunohistochemical criteria for delayed maturation of gonocytes and pre-CIS.


Assuntos
Biópsia/métodos , Carcinoma in Situ/patologia , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Testiculares/patologia , Adulto , Biomarcadores Tumorais/análise , Carcinoma in Situ/química , Pré-Escolar , Detecção Precoce de Câncer/métodos , Humanos , Masculino , Neoplasias Embrionárias de Células Germinativas/química , Neoplasias Testiculares/química
13.
Int J Androl ; 34(4 Pt 2): e160-74, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21631526

RESUMO

OCT3/4, NANOG, SOX2 and, most recently, LIN28 have been identified as key regulators of pluripotency in mammalian embryonic and induced stem cells, and are proven to be crucial for generation of the mouse germ-cell lineage. These factors are a hallmark of certain histological types of germ-cell tumours (GCTs). Here, we report novel information on the temporal and spatial expression pattern of LIN28 during normal human male germ-cell development as well as various types of GCTs. To investigate LIN28 expression, immunohistochemical analyses and quantitative proximity ligation assay-based TaqMan protein assays were applied on snap-frozen and formalin-fixed, paraffin-embedded samples as well as representative cell lines. LIN28 was found in primordial germ cells, gonocytes and pre-spermatogonia, in contrast to OCT3/4 and NANOG, which were found only in the first two stages. LIN28 was also found in all precursor lesions (carcinoma in situ and gonadoblastoma) of type II GCTs, as well as the invasive components seminoma and the non-seminomatous elements embryonal carcinoma and yolk sac tumour. Choriocarcinoma showed a heterogeneous pattern, while teratomas and spermatocytic seminomas (type III GCTs) were negative. This expression pattern suggests that LIN28 is associated with malignant behaviour of type II GCTs. Cell line experiments involving siRNA knockdown of LIN28, OCT3/4 and SOX2 showed that LIN28 plays a role in the maintenance of the undifferentiated state of both seminoma and embryonal carcinoma, closely linked to, and likely upstream of OCT3/4 and NANOG. In conclusion, LIN28 regulates the differentiation status of seminoma and embryonal carcinoma and is likely to play a related role in normal human germ-cell development.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Células Germinativas/metabolismo , Neoplasias Embrionárias de Células Germinativas/metabolismo , Neoplasias Testiculares/patologia , Biomarcadores Tumorais/análise , Carcinoma in Situ/patologia , Carcinoma Embrionário/patologia , Diferenciação Celular , Células Cultivadas , Coriocarcinoma/patologia , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Tumor do Seio Endodérmico/patologia , Células Germinativas/química , Gonadoblastoma , Proteínas de Homeodomínio/biossíntese , Humanos , Masculino , Proteína Homeobox Nanog , Neoplasias Embrionárias de Células Germinativas/patologia , Fator 3 de Transcrição de Octâmero/biossíntese , Proteínas de Transporte de Cátions Orgânicos/biossíntese , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Interferência de RNA , RNA Interferente Pequeno , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição SOXB1/biossíntese , Seminoma/patologia , Espermatogônias , Testículo/química , Testículo/metabolismo , Testículo/patologia
14.
BMC Med Genet ; 11: 131, 2010 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-20849656

RESUMO

BACKGROUND: Sex determining factor (SRY) located on the short arm of the Y chromosome, plays an important role in initiating male sex determination, resulting in development of testicular tissue. Presence of the SRY gene in females results in XY sex reversal and increased risk of gonadal germ cell tumours if the karyotype also includes the so-called GonadoBlastoma on the Y chromosome (GBY) region. The majority of mutations within the SRY gene are de novo affecting only a single individual in the family. The mutations within the high-mobility group (HMG) region have the potential to affect its DNA binding activity. CASE PRESENTATION: We performed G- and R-banding cytogenetic analysis of the patient and her family members including her father. We also performed molecular genetic analysis of SRY gene. Cytogenetic analysis in the patient (Turner Syndrome) revealed the mosaic karyotype as 45, X/46, XY (79%/21% respectively) while her father (milder features with testicular dysgenesis syndrome) has a normal male karyotype (46, XY). Using molecular approach, we screened the patient and her father for mutations in the SRY gene. Both patient and her father showed the same deletion of cytosine within HMG box resulting in frame shift mutation (L94fsX180), the father in a mosaic pattern. Histological examination of the gonads from the patient revealed the presence of gonadoblastoma formation, while the father presented with oligoasthenozoospermia and a testicular seminoma. The frameshift mutation at this codon is novel, and may result in a mutated SRY protein. CONCLUSION: Our results suggest that lack of a second sex chromosome in majority cells of the patient may have triggered the short stature and primary infertility, and the mutated SRY protein may be associated with the development of gonadoblastoma. It is of importance to note that mosaic patients without a SRY mutation also have a risk for malignant germ cell tumors.


Assuntos
Mosaicismo , Linhagem , Proteína da Região Y Determinante do Sexo/genética , Síndrome de Turner/genética , Adulto , Feminino , Mutação da Fase de Leitura , Humanos , Masculino , Pessoa de Meia-Idade
15.
Int J Androl ; 33(4): 597-603, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-19845800

RESUMO

Testicular microlithiasis (TM) is sometimes observed during scrotal ultrasound examinations in men. It has been suggested that TM is more prevalent in testes of men at risk for testicular carcinoma in situ (CIS), the precursor cells of all testicular germ cell tumours (TGCT). We have performed a retrospective analysis of ultrasound images and additional clinical data of a selected cohort of men and have determined the risk factor of TM and other ultrasound abnormalities for testicular CIS. Between 2002 and 2007, 176 testicular biopsies were performed in men with abnormalities found on the scrotal ultrasound. TM was found in 76/176 men (43.2%) and CIS was diagnosed in 20 of these men (26.3%). Here, we focused on the group of 76 men with TM to determine additional risk factors, besides TM, for CIS. In both groups, those with and without CIS, reproductive hormones, scrotal ultrasound images and patient history were compared. Predictive ultrasound findings for CIS were TM (sensitivity 100%, 95% CI: 0.8-1.0; specificity 64.1%, 95% CI: 0.6-0.7; PPV 26.3%, 95% CI: 0.2-0.4) and within this group an inhomogeneous testicular parenchyma (OR 16.1, 95% CI 2.4-106.8; sensitivity 75.0%, 95% CI: 0.5-0.9; specificity 79.0%, 95% CI: 0.7-0.9; PPV 50.0%, 95% CI: 0.3-0.7). Other significantly ultrasound characteristics for CIS in this population with TM were clusters of TM (p = 0.02) and intra-testicular lesions (p = 0.01). Men with CIS were found to have significantly lower values of inhibin-B (p = 0.02). Clusters of TM, intra-testicular lesions and lower values of inhibin-B were not significantly different in logistic regression analysis. TM on scrotal ultrasound of men with risk factors for TGCT and men with clinical signs of testicular maldevelopment has a high predictive value for CIS. However, the predictive value of an inhomogeneous testicular parenchyma, besides TM, for CIS is much higher.


Assuntos
Carcinoma in Situ/diagnóstico por imagem , Litíase/diagnóstico por imagem , Doenças Testiculares/diagnóstico por imagem , Neoplasias Testiculares/diagnóstico por imagem , Testículo/diagnóstico por imagem , Adulto , Humanos , Inibinas/sangue , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Risco , Escroto/diagnóstico por imagem , Neoplasias Testiculares/etiologia , Ultrassonografia
16.
Int J Androl ; 32(4): 279-87, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19207616

RESUMO

Testicular microlithiasis (TM) has been associated with testicular germ cell tumours (TGCTs) in adolescents and adults and with its precursor carcinoma in situ (CIS). A clear definition of TM and the need for further diagnostics and follow-up is lacking. We reviewed the literature of TM and its association with TGCT/CIS and current follow-up advises and propose a management approach based on associated risk factors for TGCT. In the literature, a wide variance of TM incidence is reported in different patient populations. A consensus concerning the malignant potential of TM has not been reached. In addition, a clear definition on TM is lacking. Although a correlation between TM and TGCT or CIS is found, precise management and follow-up schedules are absent. We suggest that all hyperechogenic foci smaller than 3 mm without shadowing should be named TM irrespective of their number. In addition, we suggest a management scheme for physicians encountering TM in daily practice. Our algorithm suggests taking a testicular biopsy in a selected patient population with at least one additional risk factor for TGCT. A long-term active follow-up schedule, including ultrasonography and physical examinations, is not indicated in the remaining patients with TM.


Assuntos
Carcinoma in Situ/diagnóstico , Litíase/diagnóstico , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Doenças Testiculares/diagnóstico , Neoplasias Testiculares/diagnóstico , Testículo/patologia , Adolescente , Adulto , Biópsia , Carcinoma in Situ/etiologia , Carcinoma in Situ/terapia , Progressão da Doença , Humanos , Imuno-Histoquímica , Incidência , Litíase/complicações , Litíase/terapia , Masculino , Neoplasias Embrionárias de Células Germinativas/etiologia , Neoplasias Embrionárias de Células Germinativas/terapia , Guias de Prática Clínica como Assunto , Valor Preditivo dos Testes , Prognóstico , Fatores de Risco , Doenças Testiculares/complicações , Doenças Testiculares/terapia , Neoplasias Testiculares/etiologia , Neoplasias Testiculares/terapia , Testículo/diagnóstico por imagem , Ultrassonografia
17.
Int J Androl ; 32(6): 666-74, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18798762

RESUMO

Carcinoma in situ (CIS) is the common precursor of all type II testicular germ cell tumors (TGCTs), i.e. seminomas and non-seminomas, which can be diagnosed using a surgical biopsy. The objective of this study was to investigate the additional value of immunohistochemistry for the diagnosis of CIS in assessing testicular biopsies taken in the context of infertility. A series of 21 infertile patients were retrieved from the Dutch pathological database (PALGA), being diagnosed with an invasive TGCT, while a matched previously obtained testicular biopsy was diagnosed as non-malignant. From 20 patients, both the invasive tumors as well as the biopsies were revised using morphology and immunohistochemistry for OCT3/4, placental-like alkaline phosphatase and c-KIT, all known established markers for CIS. The presence of CIS or invasive malignancies was scored. There are no interventions. Morphological criteria alone allowed an experienced pathologist in TGCTs to diagnose CIS in five and an invasive tumor in two cases (total n = 7, 35%). Application of immunohistochemistry resulted in the identification of an additional four cases of CIS (total n = 11, 55%, additional value of 20%). The initial correct diagnosis of CIS could have prevented a second gonadectomy in four patients (20%). This study, for the first time, really shows that time of progression from CIS to seminoma is longer than to non-seminoma. Our study demonstrates that immunohistochemistry should be performed for the diagnosis of CIS of the testis on single biopsies obtained because of infertility, resulting in an extra diagnostic yield of at least 20%. Application of this protocol will allow early diagnosis, and therefore prevent any adverse anti-cancer treatment sequelae including gonadectomy, and requiring life long androgen supplementation in some patients.


Assuntos
Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Testiculares/diagnóstico , Neoplasias Testiculares/patologia , Adolescente , Adulto , Fosfatase Alcalina , Biópsia , Carcinoma/patologia , Humanos , Imuno-Histoquímica , Isoenzimas , Masculino , Seminoma/patologia , Testículo/patologia
18.
Andrology ; 7(4): 463-468, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30786164

RESUMO

BACKGROUND: The microRNA-371a-3p (miR-371a-3p) has been reported to be an informative liquid biopsy (serum and plasma) molecular biomarker for both diagnosis and follow-up of patients with a malignant (testicular) germ cell tumor ((T)GCT). It is expressed in all histological cancer elements, with the exception of mature teratoma. However, normal testis, semen, and serum of males with a disrupted testicular integrity without a TGCT may contain miR-371a-3p levels above threshold, of which the cellular origin is unknown. OBJECTIVES: Therefore, a series of relevant tissues (frozen and formalin-fixed paraffin-embedded (FFPE), when available) from the complete male urogenital tract (i.e., kidney to urethra and testis to urethra) and semen was investigated for miR-371a-3p levels using targeted quantitative RT-PCR (qRT-PCR). MATERIALS AND METHODS: In total, semen of males with normospermia (n = 11) and oligospermia (n = 3) was investigated, as well as 88 samples derived from 32 different patients. The samples represented one set of tissues related to the entire male urogenital tract (11 anatomical locations), three sets for 10 locations, and four sets for six locations. RESULTS: All testis parenchyma (n = 17) cases showed low miR-371a-3p levels. Eight out of 14 (57%) semen samples showed detectable miR-371a-3p levels, irrespective of the amount of motile spermatozoa, but related to sperm concentration and matched Johnsen score (Spearman's rho correlation coefficient 0.849 and 0.871, p = 0.000, respectively). In all other tissues investigated, miR-371a-3p could not be detected. DISCUSSION: This study demonstrates that the miR-371a-3p in healthy adult males is solely derived from the germ cell compartment. CONCLUSIONS: The observation is important in the context of applying miR-371a-3p as molecular liquid biopsy biomarker for diagnosis and follow-up of patients with malignant (T)GCT. Moreover, miR-371a-3p might be an informative seminal biomarker for testicular germ cell composition.


Assuntos
Genitália Masculina/metabolismo , MicroRNAs/metabolismo , Sêmen/metabolismo , Sistema Urinário/metabolismo , Humanos , Masculino , Oligospermia/metabolismo , Valores de Referência
19.
Eur J Endocrinol ; 177(5): K13-K20, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28819015

RESUMO

Cushing syndrome (CS) during pregnancy is a rare condition with only a few cases reported in the literature. Misdiagnosis of CS is common because of overlapping features like fatigue, weight gain, striae and emotional changes that can occur during normal pregnancy. Changes in maternal hormones and their binding proteins complicate assessment of glucocorticoid hormone levels during gestation. CS during pregnancy is most frequently due to an adrenal adenoma and to a lesser degree to adrenocorticotropic hormone (ACTH) hypersecretion by a pituitary adenoma. Furthermore, aberrant expression of luteinizing hormone (LH) receptors in the adrenal cortex has been suggested to be involved in the pathogenesis of adrenal CS during pregnancy. We report three pregnant women with ACTH-independent Cushing's syndrome and an adrenal tumor. After uncomplicated delivery, patient 1 underwent in vivo testing for aberrant hormone receptor expression by the adenoma. Cortisol responses were found after administration of luteinizing hormone-releasing hormone (LHRH), human chorionic gonadotropin (hCG), glucagon, vasopressin and a standard mixed meal. All patients were treated with laparoscopic adrenalectomy. Adrenal tumor tissue of two patients showed positive immunohistochemical staining of LH receptors. Considering the cortisol responses to LHRH and hCG, and the development of CS during pregnancy in these patients, it is likely that ACTH-independent hypercortisolism was induced by the pregnancy-associated rise in hCG levels that activated aberrantly expressed LH receptors in the adrenal adenoma. Remarkably, adrenal adenomas may simultaneously express multiple aberrant receptors and individual ligands may play a role in the regulation of cortisol production in CS during pregnancy.


Assuntos
Síndrome de Cushing/sangue , Síndrome de Cushing/diagnóstico por imagem , Complicações na Gravidez/sangue , Complicações na Gravidez/diagnóstico por imagem , Adulto , Síndrome de Cushing/complicações , Feminino , Humanos , Recém-Nascido , Gravidez , Ultrassonografia Pré-Natal/métodos
20.
J Natl Cancer Inst ; 86(14): 1070-5, 1994 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-8021956

RESUMO

BACKGROUND: Genomic imprinting, resulting in the nonequivalence of expression of homologue genes depending on their parental origin, is an important determinant of the developmental potential of embryonic cells. The expression of two genes, one termed H19 and the other IGF2, has been found to be necessary for proper embryonal development in humans. Both the murine and human H19 and IGF2 genes are normally characterized by monoallelic expression. PURPOSE: Because testicular germ cell tumors of adults originate from an early germ cell and, to a certain extent, mimic normal embryonal development, we investigated the patterns of allelic expression of the H19 and IGF2 genes in these tumors to determine if genomic imprinting, or a disturbance of it, is involved in their pathogenesis. METHODS: Specimens of normal tissue and tumor tissue were obtained from 20 patients with testicular germ cell tumors; 10 of the patients had seminomas and 10 had nonseminomatous germ cell tumors. To determine if there was heterozygosity of the Alu I and Apa I restriction site polymorphism in the H19 and IGF2 genes, respectively, DNA was isolated from cells of the peripheral blood of these patients, then subjected to polymerase chain reaction (PCR) amplification, restriction enzyme digestion, and electrophoresis in agarose gels. If heterozygosity was determined, a similar analysis was performed on complementary DNA (cDNA) obtained from matched tumor RNA by reverse transcription and subsequent PCR amplification (RT-PCR). If monoallelic expression was found, matched tumor DNA was studied for possible deletions. RESULTS: Tumor samples from 14 of 20 and 11 of 20 patients were informative for allelic expression patterns of the H19 and IGF2 genes, respectively. Analysis of the products of RT-PCR showed biallelic expression of the H19 gene in 12 testicular germ cell tumors (patients numbered 6, 8-13, 15, 16, and 18-20) and of the IGF2 gene in 10 testicular germ cell tumors (patients numbered 1, 3, 6, 8-13, and 15-20). The three remaining tumors (patients numbered 2, 4, and 5) had lost the nonexpressed allele. CONCLUSIONS: In contrast to normally developing embryos, testicular germ cell tumors show a consistent expression of both parental alleles of the H19 and IGF2 genes. IMPLICATIONS: Testicular germ cell tumors of adults may develop from precursor cells in which the imprinting has been either erased or subjected to a consistent relaxation of its effect.


Assuntos
Alelos , Regulação Neoplásica da Expressão Gênica/genética , Germinoma/genética , Neoplasias Testiculares/genética , Sequência de Bases , DNA de Neoplasias/genética , Humanos , Masculino , Dados de Sequência Molecular , Seminoma/genética
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