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28 result(s) for "Seminoma - classification"
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MicroRNA and transcription factor co-regulatory networks and subtype classification of seminoma and non-seminoma in testicular germ cell tumors
Recent studies have revealed that feed-forward loops (FFLs) as regulatory motifs have synergistic roles in cellular systems and their disruption may cause diseases including cancer. FFLs may include two regulators such as transcription factors (TFs) and microRNAs (miRNAs). In this study, we extensively investigated TF and miRNA regulation pairs, their FFLs, and TF-miRNA mediated regulatory networks in two major types of testicular germ cell tumors (TGCT): seminoma (SE) and non-seminoma (NSE). Specifically, we identified differentially expressed mRNA genes and miRNAs in 103 tumors using the transcriptomic data from The Cancer Genome Atlas. Next, we determined significantly correlated TF-gene/miRNA and miRNA-gene/TF pairs with regulation direction. Subsequently, we determined 288 and 664 dysregulated TF-miRNA-gene FFLs in SE and NSE, respectively. By constructing dysregulated FFL networks, we found that many hub nodes (12 out of 30 for SE and 8 out of 32 for NSE) in the top ranked FFLs could predict subtype-classification (Random Forest classifier, average accuracy ≥90%). These hub molecules were validated by an independent dataset. Our network analysis pinpointed several SE-specific dysregulated miRNAs (miR-200c-3p, miR-25-3p, and miR-302a-3p) and genes ( EPHA2, JUN, KLF4, PLXDC2, RND3, SPI1 , and TIMP3 ) and NSE-specific dysregulated miRNAs (miR-367-3p, miR-519d-3p, and miR-96-5p) and genes ( NR2F1 and NR2F2 ). This study is the first systematic investigation of TF and miRNA regulation and their co-regulation in two major TGCT subtypes.
Testicular germ-cell tumours in a broader perspective
Key Points Germ-cell tumours (GCTs) of all anatomical sites can be classified into five groups, characterized by their chromosomal complement and developmental potential. The most significant recurrent chromosomal aberrations in type I yolk-sac tumours are loss of 1p, 4 and 6q, and gain of 1q, 12(p13) and 20q. In type II seminomas and non-seminomatous GCTs, the most significant recurrent chromosomal aberrations are gain of 7, 8, 12p, 21 and X, and loss of chromosomes 1p, 11, 13 and 18. Aberrations of 12p are the only recurrent structural abnormalities in type II GCTs. In type III spermatocytic seminomas, gain of chromosome 9 is most common. The originating cell is most probably a primitive germ cell of which the developmental potential differs according to its stage of maturation and pattern of genomic imprinting. Animal models are available for the different groups of GCTs, except for the type II seminomas and non-seminomatous GCTs. An activating KIT mutation in codon 816 is an early pathogenetic event in bilateral testicular seminomas and non-seminomatous GCTs. The transcription factor OCT3/4, a characteristic of primordial germ cells and pluripotent stem cells, is a new and robust diagnostic marker for type II seminomas and non-seminomatous GCTs, including their intratubular precursor. Treatment sensitivity and resistance of GCTs probably correlates with retention and loss of embryonic characteristics (in particular, DNA-repair deficiency), respectively. The germ-cell tumours are a fascinating group of neoplasms because of their unusual biology and the spectacular therapeutic results that have been obtained in these tumours. Traditionally, this group of neoplasms is presented in an organ-oriented approach. However, recent clinical and experimental data convincingly demonstrate that these neoplasms are one disease with separate entities that can manifest themselves in different anatomical sites. We propose five entities, in which the developmental potential is determined by the maturation stage and imprinting status of the originating germ cell. Recent progress begins to explain the apparent unpredictable development of germ-cell tumours and offers a basis for understanding their exquisite sensitivity to therapy.
Contemporary North-American population-based validation of the International Germ Cell Consensus Classification for metastatic germ cell tumors of the testis
BackgroundThe International Germ Cell Consensus Classification (IGCCC) is the recommended stratification scheme for newly diagnosed metastatic seminoma (mSGCT) and non-seminoma germ cell tumor (mNSGCT) patients. However, a contemporary North-American population-based validation has never been completed and represented our focus.Materials and methodsWe identified mSGCT and mNSGCT patients within the SEER database (2004–2015). The IGCCC criteria were used for stratification into prognostic groups. Kaplan–Meier (KM) derived actuarial 5-year overall survival (OS) rates were calculated. In addition, cumulative incidence plots tested cancer-specific (CSM) and other-cause mortality (OCM) rates.ResultsOf 321 mSGCT patients, 190 (59.2%) and 131 (40.8%), respectively, fulfilled good and intermediate prognosis criteria. Of 803 mNSGCT patients, 209 (26.1%), 100 (12.4%), and 494 (61.5%), respectively, fulfilled good, intermediate, and poor prognosis criteria. In mSGCT patients, actuarial KM derived 5-year OS was 87% and 78% for, respectively, good and intermediate prognosis groups (p = 0.02). In cumulative incidence analyses, statistically significant differences were recorded for CSM but not for OCM between good versus intermediate prognosis groups. In mNSGCT patients, actuarial KM derived 5-year OS was 89%, 75% and 60% for, respectively, good, intermediate, and poor prognosis groups (p < 0.001). In cumulative incidence analyses, statistically significant differences were recorded for both CSM and OCM between good, intermediate, and poor prognosis groups.ConclusionsOur findings represent the first population-based validation of the IGCCC in contemporary North-American mSGCT and mNSGCT patients. The recorded OM rates closely replicate those of the original publication, except for better survival of poor prognosis mNSGCT patients.
Canine testicular tumors: two types of seminomas can be differentiated by immunohistochemistry
Background Testicular tumors are the most common genital neoplasms in male dogs, with Leydig cell tumors (LCT), seminomas (SEM), and Sertoli cell tumors (SCT) the most common forms. Human SEM are classified as classical (CSEM) or spermatocytic (SSEM). Intratubular germ cell neoplasia of undifferentiated origin (IGCNU) is another form of human testicular tumor. The aim of this study was to verify that CSEM/SSEM classification is valid in dogs and confirm the existence of canine IGCNU. Results Testicular tumors were found in 46% of dogs at necropsy and accounted for 7% of tumors biopsied. The median age of dogs with tumors at necropsy was 10.16 years; median age at positive biopsy was 10.24 years. The most common tumors, in decreasing order, were LCT, mixed tumors, SEM and SCT at necropsy, and SEM, SCT, mixed tumors, LCT, peripheral nerve sheath tumor, and teratoma in the biopsy group. IGCNU was found in 3% of testicles at necropsy and in 3% of biopsy samples. Two dogs had testicular tumor metastasis. Expression of c-KIT was most common in SEM and seminomatous components of mixed tumors. PLAP was mostly expressed in IGCNU, SEM, teratoma, and some mixed tumors. Cytokeratin was mainly expressed in SCT. CD30 expression was low in both groups. Conclusions The high tumor incidence at necropsy can be attributed to older age. Tumor incidence in biopsy samples, dog age, and histological classification were consistent with previous studies. The higher incidence of SEM and SCT in the biopsy group probably resulted from the obvious clinical expression of these tumor types. The low incidence of metastasis confirmed the predominance of benign tumors. Low CD30 expression confirmed the low incidence of testicular embryonal carcinoma. Cytokeratin helps differentiate stromal tumors, especially SCT, from germ cell tumors. Histology and c-KIT and PLAP expression indicate that IGCNU exists in dogs. Expression of c-KIT and PLAP confirmed that CSEM and SSEM classification is valid in dogs.
Clinical implications of the American Joint Committee on Cancer (AJCC) 8th edition update in seminoma pT1 subclassification
Background Seminoma accounts for 30–50% of testicular germ cell tumors (TGCT)—the most common solid malignancy in men aged 15–35 years. The American Joint Committee on Cancer (AJCC) 8th edition (2018) created the subclassifications pT1a (tumor size < 3 cm) and pT1b (≥ 3 cm), despite not being universally recognized. Rete testis invasion (RTI) and tumor size > 4 cm are considered features associated with a higher recurrence risk, but not formally used for staging. The authors propose further understanding the subclassification’s potential impact in clinical practice, by summarizing current evidence and reviewing clinical cases in their institutions. Methods All consecutive cases of seminoma stage I, pT1 treated in two institutions between January 2005 and December 2016 were included. Clinical data were retrieved, and variables were analyzed using SPSS. Relevant literature on the topic was reviewed. Results Seminoma pT1 was identified in 58 patients. By using newly AJCC criteria, 29 (50%) would have been staged as pT1a and 29 (50%) pT1b. Median age at diagnosis was similar (33 in pT1a vs 32 in pT1b). Median follow-up time 5.8 years. Almost half (45%) of pT1b patients had a tumor size < 4 cm. The majority of either pT1a or pT1b were treated with chemotherapy or radiotherapy, reflecting more intensive approaches in the past. Three retroperitoneal recurrences were recorded (two in pT1a, one in pT1b, all under surveillance protocol); no deaths occurred. RTI and extensive necrosis (EN) were associated with pT1b ( P  <  0.0001 and P  = 0.023, respectively), known adverse biological features. Conclusions In our population, the exploratory analysis of the newly created AJCC criteria showed no significant difference in recurrence or death, although pT1b was associated with adverse biomarkers, such as RTI and EN, but its clinical relevance remains incompletely understood. Our results confirm an excellent prognosis, regardless of subcategorization, thus a larger population and a longer follow-up time are needed to understand prospectively the impact of the recently updated criteria. We would recommend using the latest AJCC staging system, although the individual risk of relapse, long-term toxicities and patient preferences should be taken into account when considering surveillance or active treatment adjuvant options.
Canine classical seminoma: a specific malignant type with human classifications is highly correlated with tumor angiogenesis
Background Human seminoma is classified as classical seminoma (SE) and spermatocytic seminoma (SS). Human SE is known to be more malignant and metastasizing more frequently than SS. Tumor angiogenesis is highly related with tumor progression and metastasis, with microvessel density (MVD) being an important parameter of metastatic potential. Canine seminoma is not yet well-established as SE or SS type including correlation with angiogenesis. We classified canine SE and SS, and then compared them to tumor associated vessels. Methods Twenty-three cases of canine seminomas (2 intratubular, 9 diffuse, and 12 intratubular/diffuse seminomas showing both intratubular and diffuse patterns) were classified as SE or SS by immunohistochemistry (IHC) using monoclonal antibody against PLAP and by PAS stain. The histopathological data were then compared to see if there was a correlation with SE or SS. Angiogenesis of seminomas were evaluated by immunohistochemical assay using polyclonal antibody against Von Willebrand factor (vWF) and by calculating the means of MVD, vessels area and perimeters using computerized image analysis. Statistical Package for Social Sciences (SPSS) program was used for various statistical analyses. Results The numbers of PLAP+/PAS+ canine SEs were 8/23 (34.8%) and PLAP-/PAS- SSs were 15/23 (61.2%). All SE cases (8/8, 100%) were intratubular/diffuse types. SS types included 2 intratubular (2/15, 13.3%), 9 diffuse (9/15, 60%), and 4 intratubular/diffuse (4/15, 26.7%) types. MVD and vascular parameters in SEs were significantly higher than in SSs, showing the highest value in the intratubular/diffuse type. Seminomas observed with neoplastic cells invasion of vessels presented higher perimeter and area values than seminomas without conformed neoplastic cells invasion. Conclusion In this study, we demonstrated a positive relationship between canine SE and tumor angiogenesis. Furthermore, we also showed that a tumor cells invasion of vessels were a correlated vascular parameter. Although metastasis of canine seminomas has rarely been reported, our results support that canine SE could have high metastatic potential similar to the human counterpart. Further studies are required to clarify the relationship between canine SE and clinical data with metastatic factors.
Laboratory markers and germ cell tumors
The International Germ Cell Consensus Classification (IGCCC) of testicular germ cell tumors (TGCT) in 1997 included three serum tumor markers, serum lactate dehydrogenase catalytic concentration (S-LD), serum alpha fetoprotein concentration (S-AFP), and serum human chorionic gonadotropin concentration (S-hCG). The recommendation should be implemented for all patients with TGCT and is also useful for patients with ovarian and extragonadal germ cell tumors. A fourth serum tumor marker for TGCT, S-LD isoenzyme 1 (S-LD-1), is also relevant for TGCT. Patients with seminoma have a raised S-LD-1 more often than a raised S-AFP and S-hCG, whereas patients with nonseminoma have a raised S-AFP more often than a raised S-LD-1 and S-hCG. A new model combining IGCCC and S-LD-1 predicts survival better than previous staging systems. LD-1 is related to a characteristic chromosomal abnormality in all types of TGCT, a high copy number of chromosome 12p. In contrast, AFP and hCG are found mainly in nonseminomatous germ cell tumors and they related to the histologic differentiation of the tumors. The different biologic background for the serum tumor markers may contribute to the difference in their clinical behavior.
Treatment of early stage testicular seminoma
Stage I and IIA/B testicular seminoma represent approximately 45% of all testicular germ cell tumours. Due to the availability of highly efficient salvage treatment, the disease-specific survival in stage I seminoma is approximately 100%, irrespective of the choice of adjuvant treatment. Radiotherapy with 26 Gy to the paraaortic/paracaval lymph nodes yields excellent cure rates of 95 98% with a favourable profile of acute and late toxicity. Likewise, phase-II trials with single-agent carboplatinum systemic treatment have demonstrated a rate of relapse of 3-4% on average. However, carboplatinum chemotherapy has to be regarded as experimental until data of phase-III trials are available. Surveillance in stage I disease is conflicted with a rate of relapse of approximately 20%. However, 80% of the patients will avoid potentially toxic overtreatment by the watch-and-wait policy. In stage IIA/B seminoma, \"dogleg\" radiotherapy with 30 Gy and 36 Gy, respectively, provides high cure rates of 90-95%. Those patients relapsing will be salvaged in almost 100% of cases. Testicular intraepithelial neoplasia (TIN) is the common precursor lesion of testicular germ cell tumours except for spermatocytic seminoma. In case of TIN in a single testis or bilateral TIN, local radiotherapy with 18 Gy is recommended as standard treatment.
Pathological complete response with cocktail chemotherapy in mediastinal seminoma
A mediastinal mass can present a diagnostic challenge, especially when symptoms necessitate urgent treatment. Mediastinal seminoma, a rare extragonadal germ cell tumour, shares clinical features with testicular seminoma, such as slow growth and high sensitivity to chemotherapy and radiotherapy. This case is of a man in his 40s presenting with cough and chest discomfort, with imaging revealing a large anterior mediastinal mass that was causing left diaphragmatic paralysis due to phrenic nerve involvement. Urgent CT of chest, abdomen and pelvis and tissue biopsy supported the diagnosis of mediastinal seminoma, prompting the immediate initiation of chemotherapy with an induction dose of etoposide and cisplatin, followed by the cisplatin, vincristine, methotrexate, bleomycin alternating with actinomycin D, cyclophosphamide, etoposide regimen. This approach led to significant tumour reduction, facilitating complete surgical resection and sparing of the right phrenic nerve. Despite early fluorodeoxyglucose-positron emission tomography suggesting residual activity, resection histopathology confirmed no malignant cells. The patient achieved a favourable outcome, underscoring the importance of rapid treatment initiation, effective chemotherapy regimens and multidisciplinary management in mediastinal seminoma cases.
DNA hypomethylation and aberrant expression of the human endogenous retrovirus ERVWE1/syncytin-1 in seminomas
Background Syncytin-1 and 2, human fusogenic glycoproteins encoded by the env genes of the endogenous retroviral loci ERVWE1 and ERVFRDE1, respectively, contribute to the differentiation of multinucleated syncytiotrophoblast in chorionic villi. In non-trophoblastic cells, however, the expression of syncytins has to be suppressed to avoid potential pathogenic effects. Previously, we have shown that the transcriptional suppression of ERVWE1 promoter is controlled epigenetically by DNA methylation and chromatin modifications. In this study, we describe the aberrant expression of syncytin-1 in biopsies of testicular germ cell tumors. Results We found efficient expression and splicing of syncytin-1 in seminomas and mixed germ cell tumors with seminoma component. Although another fusogenic gene, syncytin-2 was also derepressed in seminomas, its expression was significantly lower than that of syncytin-1. Neither the transcription factor GCM1 nor the increased copy number of ERVWE1 were sufficient for this aberrant expression of syncytin-1 in seminomas. In accordance with our recent finding of the highly increased expression of TET1 dioxygenase in most seminomas, the ERVWE1 promoter was significantly hypomethylated in comparison with the matched controls. In contrast, 5-hydroxymethylcytosine levels were not detectable at the ERVWE1 promoter. We further describe that another endogenous retroviral element adjacent to ERVWE1 remains transcriptionally suppressed and two additional HERV-W family members are only slightly upregulated in seminomas. Conclusions We conclude that DNA demethylation of the ERVWE1 promoter in seminomas is a prerequisite for syncytin-1 derepression. We propose the spliced syncytin-1 expression as a marker of seminoma and suggest that aberrant expression of endogenous retroviruses might be a correlate of the hypomethylated genome of seminomas.