Search Results (310)

Background/Objectives: The Germ Cell Theory of cancer posits that human primordial germ cells (hPGCs) are the cells of origin for malignancies. While this theory is well established for germ cell cancers, a germ cell origin for somatic cancers has been largely overlooked despite clinical observations of malignant somatic transformation (MST), wherein germ cell cancers give rise to diverse somatic cancer phenotypes, often without additional mutations. Methods: To test the Germ Cell Theory experimentally in somatic cancer, we established a virus-driven MST model linking hPGC-like cells (hPGCLCs) to Merkel cell polyomavirus (MCPyV)-positive Merkel cell carcinoma (MCC), a highly aggressive somatic cancer with a germ cell cancer-like, low-mutation epigenetic profile. The MCPyV genome was transduced into human induced pluripotent stem cells (hiPSCs) or hPGC-like cells by lentiviral transfection, followed by xenotransplantation. Results: Virus-positive MCC (VP-MCC)-like tumors were consistently induced without additional oncogenic mutations. These tumors recapitulated VP-MCC’s high-grade neuroendocrine carcinoma histology and molecular profiles. DNA methylation analysis revealed near-complete global hypomethylation in VP-MCC-like tumors, matching the unique epigenetic state of late-stage hPGCs. Notably, pluripotent intermediates were neither necessary nor sufficient for MST; transformation required acquisition of a late-hPGC-like epigenetic state. Conclusions: This is the first MST model of a somatic cancer arising through an aberrant germline-to-soma transition. Our findings unify VP-MCC and germ cell cancer biology, challenge mutation- and soma-centric paradigms, and provide a tractable platform to investigate developmental and epigenetic mechanisms of oncogenesis. This MST model supports a unifying germ cell origin for both germ cell and non-germ cell somatic malignancies. Full article

This study aims to investigate the molecular mechanisms underlying germ cell tumors (GCTs), focusing specifically on seminomas and teratomas. By analyzing gene expression profiles and miRNA interactions, the goal is to identify key regulatory miRNAs and signaling pathways that differentiate these tumor types and could serve as important regulators for therapy development. Raw data for seminomas and teratomas were extracted from the GEO database, and gene hubs were identified using STRING and Gephi. Signaling pathways and functional annotations were analyzed using miRPathDB, while miRNA–gene interactions were explored via miRWalk. Hub miRNAs were filtered and confirmed using miRDB. This study highlights significant changes in gene expression diversity between tumor and normal gonadal tissues, providing insights into the molecular dynamics of seminomas and teratomas. Distinctions between seminomas and teratomas were identified, shifting the focus toward miRNAs to discover more precise and novel therapeutic approaches. The hub genes of seminomas and teratomas were identified separately. MiRNAs targeting these hub genes were also determined and confirmed. These miRNAs collectively influence essential oncogenic pathways—confirming hsa-miR-138-5p as a regulator of pathways such as Hippo signaling, transcriptional misregulation in cancer, and microRNA cancer signaling in seminomas, and hsa-miR-200b-3p as a regulator of p53 signaling, T cell receptor signaling, and pathways including PI3K/AKT, MAPK/ERK, and Wnt/β-catenin in teratomas—confirming their potential as promising candidates for subtype-specific therapeutic intervention. MiRNAs identified through bioinformatics analyses, and their predicted regulatory roles in key oncogenic pathways, represent potential therapeutic targets or regulators of biological processes. However, further experimental validation is needed to confirm these findings. Full article

Background: Seminoma is the most common subtype of testicular germ cell tumors in young men; however, the contribution of tumor-associated macrophages (TAMs) to disease progression remains insufficiently understood. This study aimed to quantitatively and phenotypically characterize CD68⁺ and CD163⁺ TAMs in non-metastatic seminomas (pT1N0M0 and pT2N0M0). Methods: This retrospective, multicenter, cohort, observational, analytical study was conducted from 1 January 2015 to 1 January 2025 at two branches of the National Medical Research Radiological Center of the Ministry of Health of the Russian Federation: the A. Tsyb Medical Radiological Research Center and the P. Hertsen Moscow Oncology Research Institute. Archived paraffin-embedded tumor samples from 96 patients and 21 samples of normal testicular tissue were analyzed using immunohistochemistry and digital morphometric analysis with QuPath software to assess macrophage density and spatial distribution. Results: Compared to normal testicular tissue, seminomas demonstrated more than a 10-fold increase in CD68⁺ TAMs and over a 100-fold increase in CD163⁺ TAMs. CD68⁺ cells predominantly localized to peripheral tumor regions, while CD163⁺ cells formed diffuse clusters in central tumor zones and around peripheral vessels. No statistically significant differences in CD68⁺ cell density were found between pT1 and pT2 stages. However, pT2 tumors showed a trend toward higher CD163⁺ TAMs density, suggesting increased M2 polarization with advancing tumor stage. Conclusions: These findings highlight the spatial and phenotypic heterogeneity of TAMs in seminoma and indicate a shift toward an immunosuppressive tumor microenvironment during local progression. Future studies should assess macrophage polarization and progression-free survival to evaluate their potential as prognostic biomarkers and therapeutic targets in seminoma. Full article

Malignant mediastinal tumors are a group representing some of the most demanding oncological challenges for early, multi-level, and successful management. The timely identification of any suspicious clinical symptomatology is urgent in achieving an accurate, staged histological diagnosis, in order to follow up with an equally detailed medical therapeutic plan (interventional or not) and determine the principal goals regarding efficient overall treatment in these patients. We report a case of a 24-year-old male patient with an incident-free prior medical history. An initial chest X-ray was performed after the patient reported short-term, consistent moderate chest pain symptomatology, early work fatigue, and shortness of breath. The following imaging procedures (chest CT, PET-CT) indicated the presence of an anterior mediastinal mass (meas. ~11 cm × 10 cm × 13 cm, SUV: 8.7), applying additional pressure upon both right heart chambers. The Alpha-Fetoprotein (aFP) blood levels had exceeded at least 50 times their normal range. Two consecutive diagnostic attempts with non-specific histological results, a negative-for-malignancy fine-needle aspiration biopsy (FNA-biopsy), and an additional tumor biopsy, performed via mini anterior (R) thoracotomy with “suspicious” cellular gatherings, were performed elsewhere. After admission to our department, an (R) Video-Assisted Thoracic Surgery (VATS) was performed, along with multiple tumor biopsies and moderate pleural effusion drainage. The tumor’s measurements had increased to DMax: 16 cm × 9 cm × 13 cm, with a severe degree of atelectasis of the Right Lower Lobe parenchyma (RLL) and a pressure-displacement effect upon the Superior Vena Cava (SVC) and the (R) heart sinus, based on data from the preoperative chest MRA. The histological report indicated elements of a combined, non-seminomatous germ-cell mediastinal tumor, posthuberal-type teratoma, and embryonal carcinoma. The imminent chemotherapeutic plan included a “BEP” (Bleomycin^®/Cisplatin^®/Etoposide^®) scheme, which needed to be modified to a “VIP” (Cisplatin^®/Etoposide^®/Ifosfamide^®) scheme, due to an acute pulmonary embolism incident. While the aFP blood levels declined, even reaching normal measurements, the tumor’s size continued to increase significantly (DMax: 28 cm × 25 cm × 13 cm), with severe localized pressure effects, rapid weight loss, and a progressively worsening clinical status. Thus, an emergency surgical intervention took place via median sternotomy, extended with a complementary “T-Shaped” mini anterior (R) thoracotomy. A large, approx. 4 Kg mediastinal tumor was extracted, with additional RML and RUL “en-bloc” segmentectomy and partial mediastinal pleura decortication. The following histological results, apart from verifying the already-known posthuberal-type teratoma, indicated additional scattered small lesions of combined high-grade rabdomyosarcoma, chondrosarcoma, and osteosarcoma, as well as numerous high-grade glioblastoma cellular gatherings. No visible findings of the previously discovered non-seminomatous germ-cell and embryonal carcinoma elements were found. The patient’s postoperative status progressively improved, allowing therapeutic management to continue with six “TIP” (Cisplatin^®/Paclitaxel^®/Ifosfamide^®) sessions, currently under his regular “follow-up” from the oncological team. This report underlines the importance of early, accurate histological identification, combined with any necessary surgical intervention, diagnostic or therapeutic, as well as the appliance of any subsequent multimodality management plan. The diversity of mediastinal tumors, especially for young patients, leaves no place for complacency. Such rare examples may manifest, with equivalent, unpredictable evolution, obliging clinical physicians to stay constantly alert and not take anything for granted. Full article

Testicular germ cell tumors (TGCTs) are the most common malignancies affecting young men between the ages of 14 and 44, accounting for about 95% of all testicular cancers. Despite being relatively rare compared to other cancers (~3.0 cases per 100,000 population, with high worldwide variability), TGCTs’ incidence is increasing, particularly in industrialized countries. The initial phase of TGCT diagnosis is performed by detecting in the blood the presence of three proteins, i.e., alpha-fetoprotein (AFP), lactate dehydrogenase (LDH), and human chorionic gonadotropin (hCG). Despite these proteins being defined as markers of TGCTs, they present limitations in specificity. Indeed, AFP is not elevated in pure seminomas; LDH serum levels can be elevated in other conditions, such as liver disease or tissue damage, and hCG can be elevated in both seminomas and non-seminomas, reducing its ability to differentiate between tumor types. However, the existence of hCG variants, characterized by distinct glycosylation profiles that are differentially expressed in TGCT types and subtypes, may increase the diagnostic and prognostic potential of this hormone. Furthermore, emerging molecular biomarkers, including miRNAs and tumor cells-related epigenetic status, may offer new promising alternatives to improve diagnostic accuracy. Nonetheless, standardized diagnostic protocols still need to be implemented. Finally, understanding the biological roles of hCG isoforms and their “canonical” (e.g., LHCGR) and “non-canonical” (e.g., TGF-βR) receptor interactions may help in understanding tumor biology and therapeutic targeting. Full article

Background/Objectives: Germ cell tumors are the most common neoplasia in males < 50 y. In two case series, thromboembolic events (TEs) were reported in 8% and 13% of patients undergoing chemotherapy, whereas arterial thromboembolic events (ATEs) in other types of cancer treated with cisplatin had a frequency of 2% in a retrospective series and 0.67% in a meta-analysis. Recent data found a frequency of 2.4% for ATE in a large cohort of testicular cancer patients. Risk factors are not clearly identified, and given the severity of these events, further exploration is needed to determine appropriate preventive measures. Methods: We performed a retrospective cohort study of 171 patients undergoing chemotherapy for germ cell tumors in two centers in Switzerland and recorded the occurrence of ATE or venous thromboembolic events (VTEs) during chemotherapy or in the 3 months after its completion. Results: of 171 patients, 33.3% underwent adjuvant chemotherapy for stage I disease. Overall, 32 patients had a TE (18.7%, 95% CI 13.3–25.5%), 26 (15.2%, 95% CI 10.3–21.7%) had VTEs, and 11 (6.4%, 95% CI 3.4–11.5%) had ATEs. Five patients had both a VTE and ATE. VTEs were associated with disease stage (II, III, or relapse, with OR 15.6, p = 0.0002), retroperitoneal lymph nodes ≥ 3.5 cm (OR 3.2, p = 0.012), LDH > 500 UI/L (OR 5.3, p = 0.0025), and age > 35 y (OR 3.4, p = 0.005). The Khorana Score (KS) varied between 1 and 2 in 96% of the patients. ATEs were associated with active smoking (OR 6.5 p = 0.010), KS of ≥2 (OR 6.4 p = 0.004), and age > 35 y (OR 6.3, p = 0.01). Conclusions: Our findings show that ATEs are more frequent in our cohort than previous reports. We found a strong association between smoking and ATEs, which should be further assessed. Platinum-induced endothelial damage may be amplified by smoking in young patients in the absence of other risk factors and preventive medication. Full article

Ovarian tumors are rare in the pediatric population, yet they are the most common type of malignancy in tumors of the female genital tract. Both non-neoplastic and neoplastic ovarian lesions are seen in children and adolescents. Most pediatric ovarian tumors are benign. Germ cell tumors constitute the majority of ovarian tumors in the pediatric cohort, and mature teratoma is the most prevalent histologic type. However, 3–8% % of ovarian tumors in children and adolescents are malignant. Accurate characterization of ovarian masses in the pediatric population is crucial to determine the appropriate treatment, which should be minimally invasive and focused on preserving fertility. Transabdominal US is the main imaging modality for the assessment of pediatric ovarian masses. MRI represents a valuable adjunct tool for the evaluation of sonographically indeterminate ovarian lesions. This technique is also recommended for tumor staging and follow-up. CT is often used in emergency situations or when there are contraindications for MRI. Imaging findings, along with clinical features and laboratory results, play a crucial role in the characterization of ovarian masses in the pediatric population. This narrative review was based on a comprehensive literature search of articles about imaging findings of ovarian masses in the pediatric population, published between 1977 and April 2025. Data were obtained from the PubMed database, using the following keywords: “imaging”, “ovarian tumors”, ovarian masses”, and “pediatric”. This article aims to provide an overview of the role of imaging in the assessment of ovarian masses in the pediatric age group. Full article

Pluripotent stem cell (PSC)-based therapies are currently in clinical trials. However, one of the main safety concerns includes the potential for cancer formation of the PSC-derived products. Currently, the teratoma in vivo assay is accepted by regulatory agencies for identifying whether PSCs have the potential to become malignant. Yolk sac elements (YSE) are one of the elements that could arise from PSC. Whereas the other malignant element, embryonal carcinoma, is thoroughly studied, this is not the case for YSE. Therefore, more research is needed to assess the nature of YSE. We propose that it is imperative to include the formation of YSE in the safety assessment of PSC due to their close resemblance to the clinical entity of yolk sac tumor (YST), a human malignant germ cell tumor (hGCT). In this review, we extrapolate knowledge from YST to better understand YSE derived from PSC. We demonstrate that both share a similar morphology and that the same characteristic immunohistochemical markers can be used for their identification. We discuss the risk these tumors pose, thereby touching upon genetic abnormalities and gene expression that characterize them, as well as possible disease mechanisms. Integrating the molecular and immunohistochemical markers identified in this review into future research will help to better address the potential malignancy associated with PSC. Full article

Background: Lung cancer, predominantly NSCLC (80%), has a poor prognosis due to late diagnosis and limited treatment efficacy. DMRTA2 (DMRT5), a transcription factor linked to neural/germ cell development, is overexpressed in NSCLC per TCGA data, indicating its potential role in tumorigenesis and as a therapeutic target. Methods: Conduct a comprehensive search of the relevant theoretical foundations. Based on this, differential expression analysis will be performed using the DESeq2 package in R on RNA-seq data from lung adenocarcinoma and lung squamous cell carcinoma in the TCGA database. The research will then employ various methods, including CRISPR genome editing, MTS assay, flow cytometry, Western blot, co-immunoprecipitation, immunofluorescence, and qRT-PCR. Results: Through experimental validation, we found that DMRTA2 mRNA is highly expressed in non-small-cell lung cancer (NSCLC) tissues and is negatively correlated with poor prognosis. DMRTA2 binds to HSP90β, inhibiting the interaction between HSP90β and p53, thereby suppressing p53 ubiquitination and nuclear export. This activates the p53 pathway, inhibiting the proliferation and invasion of lung cancer cells. Conclusions: In NSCLC, DMRTA2 acts as a context-dependent regulator, stabilizing wild-type p53 through competitive HSP90β binding to suppress tumors, while in p53-compromised cells, potentially engaging HSP90β or alternative pathways to promote malignancy. Its dual localization and transport interactions reveal multifunctional, stress-responsive roles beyond transcription. Full article

Type II testicular germ cell tumors (TGCTs) are the most common solid malignancies in young men and are classified into seminomas and non-seminomatous subtypes. Seminomas are known for their highly pro-inflammatory tumor microenvironment (TME) with abundant immune cell infiltration. While previous work has demonstrated that the seminoma-derived cell line TCam-2 induces immune cell activation in co-culture and undergoes phenotypic changes itself, the underlying mechanisms remained unclear. To explore the role of direct cell–cell interaction and the effects mediated by soluble mediators such as cytokines, we conducted co-culture experiments of TCam-2 cells with purified human T cells or monocytes, including Transwell assays and treatments with IL-6, TNFα, or their respective blocking antibodies Tocilizumab and Adalimumab. In this way, we found that immune cell activation, indicated by enhanced secretion of pro-inflammatory cytokines and an upregulation of activation markers, strongly depended on direct physical contact between both cell types. Nonetheless, we also unveiled the role of soluble mediators in both immune cell activation and promoting a shift in TCam-2 cells from a seminoma-like phenotype to a more dedifferentiated phenotype, suggesting that cytokines critically shape the TME. These observations highlight the complexity of tumor–immune interactions in the seminoma microenvironment, offering new insight into immune-driven dynamics in TGCTs. Full article

Background/Objectives: Cowden syndrome (or PTEN hamartoma tumor syndrome) (CS/PHTS) belongs to a group of inherited disorders associated with the development of multiple hamartomas. The clinical presentation of patients may include dysmorphic facial features, macrocephaly, developmental delay, and multiple benign and malignant tumors of various localizations. At the same time, only thyroid cancer is thought to have an increased risk in childhood. Skin lesions in CS/PHTS occur in 90–100% of patients and include multiple tricholemmoma, papilloma, acral keratosis, pigmentation changes, as well as rarer forms like vascular malformations, fibromas, neuromas, melanoma, and basal cell carcinoma. Methods: Next-generation sequencing and Sanger sequencing were used to search for PTEN genetic variants. A histological and immunohistochemical examination of tumor biopsies and skin lesions was performed. Results: A total of 13 patients from six families with CS/PHTS, including 10 children, were described. Seven pediatric patients belonged to families with paternal transmission of the PTEN pathogenic variants, while three others were de novo cases. Atypical manifestations in CS/PHTS were diffuse large B-cell lymphoma in one adult, a renal cell carcinoma, three germ cell tumors, and a linear epidermal nevus in pediatric patients. A literature review of the identified pathogenic variants in the PTEN gene was performed, assessing their clinical significance and analyzing the traditional and modified diagnostic criteria as applied to the pediatric population. Conclusions: Taking into account the low incidence of CS/PHTS, the data presented significantly expand our current understanding of this disease and guide physicians to consider a wider range of possible malignant neoplasms in pediatric patients with CS/PHTS. Full article

Background/Objectives: Metastatic testicular germ cell tumor (mGCT) is a highly curable disease with first-line cisplatin-based combination chemotherapy. This study aims to evaluate the clinicopathological characteristics and survival outcomes of patients with metastatic testicular cancer in a nationwide multicenter cohort. Methods: This multicenter retrospective cohort study included 316 male patients diagnosed with mGCT who were treated with first-line cisplatin-based chemotherapy across 10 institutions in Turkey between 2011 and 2024. Clinical and pathological data, including International Germ Cell Cancer Collaborative Group (IGCCCG) risk classification, treatment details, and survival outcomes, were analyzed. Results: The median age of the cohort was 28 years, and 76.3% of patients were diagnosed with non-seminoma. According to IGCCCG risk stratification, 53.2% had good-risk, 25.3% intermediate-risk, and 21.5% poor-risk disease. Median follow-up was 38.4 months. Among patients with seminoma, the 5-year overall survival (OS) rate was 100% in the good-risk group and 87.5% in the intermediate-risk group. In patients with non-seminoma, 5-year OS rates were 96.6%, 86.9%, and 65.1% in the good-, intermediate-, and poor-risk groups, respectively. Among 125 patients who received salvage treatment, high-dose chemotherapy (HDCT) significantly improved survival in the International Prognostic Factors Study Group (IPFSG) very high-risk group (3-year OS: 55.0% vs. 16.3% with conventional-dose chemotherapy (CDCT), p = 0.007). Conclusions: This study provides the first large-scale nationwide dataset on mGCT outcomes in Turkey, demonstrating overall survival rates comparable to international cohorts. The findings emphasize the importance of a multidisciplinary approach, adherence to treatment guidelines, and optimal surgical interventions in improving patient outcomes. Full article

Background: Testicular germ cell tumors (GCTs) are highly curable malignancies, particularly when diagnosed early. However, cardiac metastases are exceedingly rare—occurring in less than 1% of cases—and pose significant diagnostic and therapeutic challenges. Intracardiac involvement is exceptionally uncommon and typically necessitates a multidisciplinary approach for optimal management. Objective: To present a rare case of metastatic testicular GCT with intracardiac extension in a young male, underscoring the diagnostic complexity and therapeutic considerations of this unusual clinical scenario. Case Report: A 23-year-old male presented with diffuse abdominal pain, dyspnea, and a palpable right testicular mass. Imaging revealed a testicular tumor with metastases to the lungs, liver, retroperitoneal lymph nodes, and a large intracardiac mass extending from the inferior vena cava into the right atrium. Histopathology confirmed a mixed-germ cell tumor consisting of 75% seminoma, 20% embryonal carcinoma, and 5% teratoma. The patient underwent radical right orchiectomy followed by chemotherapy with the BEP regimen (bleomycin, etoposide, cisplatin). Cardiac magnetic resonance imaging confirmed the intracardiac mass, which significantly decreased in size after treatment. Serum tumor markers (AFP and β-hCG) also showed substantial post-treatment declines, corresponding with clinical improvement. Conclusions: This case highlights a rare presentation of metastatic testicular GCT with intracardiac involvement, emphasizing the importance of recognizing atypical metastases. Despite its complexity, the patient responded well to chemotherapy, reinforcing the effectiveness of current treatments. Long-term follow-up and a multidisciplinary approach are essential for monitoring recurrence and complications, contributing to the understanding of rare metastatic patterns and the need for further research. Full article

Background/Objectives: Pediatric gonadal tumors are rare tumors, and germ cell tumors (GCTs) are the most common subgroup. GCTs are heterogeneous tumors and have different subtypes that can be either benign or malignant. Therefore, extensive sampling of the resected tumor is required to obtain an accurate diagnosis. Higher harmonic generation microscopy (HHGM) is an innovative imaging technique that enables rapid visualization of fresh tissue without the need for preparation or staining. This makes it particularly valuable for sample selection, as the tissue can be reused for further analysis. This study aims to evaluate the accuracy of pathologists detecting normal gonadal tissue, germ cell tumors, and other pediatric gonadal tumors in HHGM images. Methods: Twenty-eight samples of twenty-two patients with a germ cell tumor or other gonadal tumor were imaged with the HHG microscope and subsequently processed for histology. Overview images of the samples were made in 10 s per mm², and high-quality images in 1 min per mm². A multi-observer study was performed with five expert pathologists. Results: Pathologists were able to differentiate between tumor and non-tumor tissue with an accuracy of 75% (21/28) on the HHGM images versus an accuracy of 89% (25/28) on the corresponding histology. Discrepancies mainly concerned teratoma cases for HHGM as well as H&E, indicating that sampling errors of these heterogeneous tumors affected the outcomes of this study adversely. Conclusions: Although the sample size was limited by the rarity of these tumors, our data show that HHGM is a promising technique for the rapid assessment of pediatric gonadal tumor samples, particularly in evaluating their representativeness. Full article

Sertoli cell-only (SCO) tubules are a histologic pattern characterized by the absence of germ cells within seminiferous tubules, leading to infertility in both humans and dogs. While its association with testicular tumors has been documented, the role of iron metabolism in SCO tubules remains unclear. This study investigates the immunolabeling of key iron-related proteins (Transferrin Receptor 1, Transferrin Receptor 2, and Ferritin Heavy chain 1) and Proliferating Cell Nuclear Antigen (PCNA) in canine SCO tubules within distinct microenvironments: seminomas, Sertoli cell tumors, and isolated. We confirm the presence and distribution of iron-related proteins in Sertoli cells as a part of a Sertoli cell-only pattern across different microenvironments. Our findings suggest a potential increase in iron uptake in association with tumors, and the cytoplasmic PCNA immunolabeling suggests a preferential activation of cell survival rather than proliferation, potentially facilitating neoplastic transformation. In contrast, Sertoli cells in the isolated Sertoli cell-only pattern exhibit nuclear PCNA immunolabeling, possibly correlated to the state of immaturity of Sertoli cells. These findings highlight the role of iron homeostasis and apoptosis in testicular tumorigenesis. Immunohistochemistry revealed that Sertoli cells in SCO tubules actively uptake iron in all conditions, yet their capacity to utilize it for proliferation appears restricted. Interestingly, PCNA labeling exhibits a pattern dependent on the microenvironment: in tumor-associated SCO tubules, it showed cytoplasmic localization, characteristic of an anti-apoptotic function, whereas isolated SCO tubules showed nuclear PCNA labeling, suggesting a potential role in DNA synthesis and repair. These findings highlight the interplay between iron homeostasis and cellular survival mechanisms, offering novel perspectives on its pathophysiology and implications for testicular cancer development. Full article