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1.
Clin Neurol Neurosurg ; 244: 108408, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38954867

RESUMO

BACKGROUND: Pure germinoma typically originates from the midline and is usually found in the pineal and suprasellar regions in 76-90 % of cases. When it is in both regions, it is considered bifocal (10 % at diagnosis). If pure germinoma is located outside of the midline, it is considered ectopic, with a global incidence of about 0.7 %. The study aims to describe the clinical and surgical approach to patients with atypical intracranial ectopic germinoma (IEG) and bifocal germinoma (BG) through a literature review with the goal to delineate the correct diagnostic and therapeutic pathway, to reduce the diagnostic delay and improve the prognosis of these patients. METHODS: A systematic review of the literature in most common electronic database (PubMed, Ovid MEDLINE and Ovid EMBASE) on IEG and BG, in according with the "PRISMA statement" criteria, from January 1990 to September 2022 was done. In addition, two rare cases of IEG and BG were reported. RESULTS: This systematic review included 16 papers (20 patients) with a final diagnosis of IEG and 30 papers (121 patients) with a final diagnosis of BG. IEGs seems to involve primary basal ganglia (40 %) and corpus callosum (40 %). For IEGs, biopsy (70 %, 14 cases out of 20) was the most common surgical approach: open approach (35 %), stereotactic minimally invasive approach (30 %) or endoscopic trans-sphenoidal approach (5 %). Partial resection was performed in 10 % of cases, whereas a total resection was performed in 20 % of cases. Also for BGs, biopsy was the most common surgical approach in 80 % of patients, whereas surgical resection (partial or total) was performed in 5.3 % of patients. CONCLUSION: IEG and BG are rare type of primary intracranial germ cell tumor, whose unusual location often can cause delays in diagnosis, which can have a significant impact on the patient's prognosis and requiring a multidisciplinary and timely approach.

2.
Front Endocrinol (Lausanne) ; 15: 1408065, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38957439

RESUMO

Purpose: The impact of delayed diagnosis on tumor-related prognosis appears to be minimal in individuals with intracranial germ cell tumors (iGCTs). However, its effect on neuroendocrine functions remains unclear. We aimed to assess the effects of delayed diagnosis on neuroendocrine function in individuals with suprasellar GCTs. Methods: We conducted a retrospective cohort study of 459 individuals with suprasellar GCTs and categorized them into two groups based on disease duration: delayed diagnosis (> 6 months) and non-delayed diagnosis (≤ 6 months). We compared endocrinological symptoms, neuroendocrine dysfunction and its grading (categorized into 0-3 grades based on severity), and recovery from neuroendocrine dysfunction in both groups. Results: Patients with delayed diagnosis exhibited higher incidences of amenorrhea, slow growth, fatigue, and polyuria/polydipsia. Neuroendocrine dysfunction, including central adrenal insufficiency (CAI), central hypothyroidism (CHT), arginine vasopressin deficiency (AVP-D), growth hormone deficiency, hypogonadism, and hyperprolactinemia, was more pronounced in the delayed diagnosis group at diagnosis, the end of treatment, and the last follow-up. Furthermore, individuals with delayed diagnosis showed higher grades of neuroendocrine dysfunction at diagnosis (OR=3.005, 95% CI 1.929-4.845, p<0.001), end of oncologic treatment (OR=4.802, 95% CI 2.878-8.004, p<0.001), and last follow-up(OR=2.335, 95% CI 1.307-4.170, p=0.005) after adjusting for confounders. Finally, less recovery, particularly in CAI, CHT, and AVP-D, was seen among the group with delayed diagnosis after treatment. Conclusion: Among individuals with suprasellar GCTs, delayed diagnosis is associated with increased, more severe, and less recovered neuroendocrine dysfunction, emphasizing the importance of early diagnosis and treatment to reduce neuroendocrine dysfunction.


Assuntos
Diagnóstico Tardio , Neoplasias Embrionárias de Células Germinativas , Humanos , Masculino , Feminino , Estudos Retrospectivos , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Adulto , Adulto Jovem , Adolescente , Prognóstico , Sistemas Neurossecretores/fisiopatologia , Pessoa de Meia-Idade , Seguimentos
3.
Clin Transl Oncol ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958901

RESUMO

Testicular germ cell tumors are the most common tumors in adolescent and young men. They are curable malignancies that should be treated with curative intent, minimizing acute and long-term side effects. Inguinal orchiectomy is the main diagnostic procedure, and is also curative for most localized tumors, while patients with unfavorable risk factors for recurrence, or those who are unable or unwilling to undergo close follow-up, may require adjuvant treatment. Patients with persistent markers after orchiectomy or advanced disease at diagnosis should be staged and classified according to the IGCCCG prognostic classification. BEP is the most recommended chemotherapy, but other schedules such as EP or VIP may be used to avoid bleomycin in some patients. Efforts should be made to avoid unnecessary delays and dose reductions wherever possible. Insufficient marker decline after each cycle is associated with poor prognosis. Management of residual masses after chemotherapy differs between patients with seminoma and non-seminoma tumors. Patients at high risk of relapse, those with refractory tumors, or those who relapse after chemotherapy should be managed by multidisciplinary teams in experienced centers. Salvage treatment for these patients includes conventional-dose chemotherapy (TIP) and/or high-dose chemotherapy, although the best regimen and strategy for each subgroup of patients is not yet well established. In late recurrences, early complete surgical resection should be performed when feasible. Given the high cure rate of TGCT, oncologists should work with patients to prevent and identify potential long-term side effects of the treatment. The above recommendations also apply to extragonadal retroperitoneal and mediastinal tumors.

4.
Diagn Pathol ; 19(1): 91, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961474

RESUMO

BACKGROUND: Chordoma, a rare malignant tumor arising from notochordal tissue, usually occurs along the spinal axis. Only a few published reports of primary lung chordomas exist. Herein, we present a case of primary lung chordoma and discuss important considerations for diagnosing rare chordomas. CASE PRESENTATION: We report a case of primary lung chordoma in a 39-year-old male with a history of testicular mixed germ-cell tumor of yolk sac and teratoma. Computed tomography revealed slow-growing solid lesions in the left lower lobe. We performed wedge resection for suspected germ-cell tumor lung metastasis. Histologically, large round or oval cells with eosinophilic cytoplasm were surrounded by large cells with granular, lightly eosinophilic cytoplasm. Tumor cells were physaliphorous. Immunohistochemistry was positive for brachyury, S-100 protein, epithelial membrane antigen, vimentin, and cytokeratin AE1/AE3, suggesting pulmonary chordoma. Re-examination of the testicular mixed germ-cell tumor revealed no notochordal elements. Although some areas were positive for brachyury staining, hematoxylin and eosin (HE) staining did not show morphological features typical of chordoma. Complementary fluorescence in situ hybridization (FISH) of the lung tumor confirmed the absence of isochromosome 12p and 12p amplification. Thus, a final diagnosis of primary lung chordoma was established. CONCLUSIONS: In patients with a history of testicular mixed germ cell tumors, comparison of histomorphology using HE and Brachyury staining of lung and testicular tumors, and analyzing isochromosome 12p and 12p amplification in lung tumors using FISH is pivotal for the diagnosis of rare lung chordomas.


Assuntos
Biomarcadores Tumorais , Cordoma , Neoplasias Pulmonares , Neoplasias Embrionárias de Células Germinativas , Neoplasias Testiculares , Humanos , Masculino , Cordoma/patologia , Cordoma/diagnóstico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/diagnóstico , Adulto , Biomarcadores Tumorais/análise , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Embrionárias de Células Germinativas/química , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Neoplasias Testiculares/patologia , Neoplasias Testiculares/diagnóstico , Neoplasias Testiculares/química , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Teratoma/patologia , Teratoma/química , Teratoma/diagnóstico
5.
Front Oncol ; 14: 1417761, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38966065

RESUMO

Objectives: Yolk sac tumors (YSTs) are rare and highly malignant ovarian malignancies that have a very poor prognosis. The aim of this study is to delineate the ultrasound and clinicopathological features of female pelvic YSTs to better understand the disease. Methods: This study was a retrospective analysis of the clinicopathological and ultrasound imaging data from 16 YST patients who received treatment at our hospital between January 2012 and August 2023. Then, the ultrasound imaging characteristics were compared with pathological findings. Results: Among the 16 patients, various degrees of serum AFP increase were observed, and CA125 levels increased in 58.33% (7 out of 12) of patients. Thirteen patients (81.25%) had tumors located in ovary, two patients (12.5%) had tumors located in the sacrococcygeal region, and one patient (6.25%) had tumors located in the mesentery. Pathologically, nine patients presented with simple yolk sac tumors and seven with mixed germ cell tumors. According to the ultrasound manifestations, YST lesions can be classified into three types. (1) the cystic type, was diagnosed in two patients who presented with a large cystic mass with regular morphology and clear boundary and dense liquid within the cyst; and (2) the cystic-solid mixed type, was diagnosed in 4 patients. On 2D ultrasound, the lesions showed a cystic-solid mixed echo, and color Doppler showed a rich blood flow signal in the solid region and cystic separation. made up of four cases. (3) In ten patients with the solid type, 2D ultrasound showed solid uniform echoes with clear boundaries. The "fissure sign" was observed in the lesion. Color Doppler displayed rich blood flow in the solid part, and PW showed low to moderate resistance index of artery (RI:0.21-0.63). On contrast-enhanced ultrasound (CEUS), rapid and high enhancement in the solid part and cystic separation was observed in 2 patients. Conclusions: Combining ultrasound features with clinical information and tumor markers provides reliable clues for the diagnosis of YST. The application of two-dimensional ultrasound and CEUS combined with patient tumor marker levels can provide a robust reference for determining the necessity of fertility-preserving surgery and postoperative chemotherapy, which can improve clinical decision-making and patient consultation.

6.
Eur Urol Open Sci ; 65: 13-19, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38966804

RESUMO

Background and objective: There is an unmet need to avoid long-term morbidity associated with standard cytotoxic treatment for low-volume metastatic seminoma. Our aim was to assess the oncological efficacy and surgical safety of retroperitoneal lymph node dissection (RPLND) as treatment in a population-based cohort of metastatic seminoma patients with limited retroperitoneal lymphadenopathy. Methods: Sixty-two seminoma patients in Norway and Sweden were included in the cohort from 2019 to 2022. Patients with lymphadenopathy ≤3 cm, having primary clinical stage (CS) IIA/B or CS I with a relapse, were operated with uni- or bilateral template RPLND, open or robot assisted. The outcome measures included surgical complications as per Clavien-Dindo, and Kaplan-Meier survival estimates for 24-mo progression-free survival (PFS) and overall survival (OS). Key findings and limitations: In the cohort, 33 (53%) had CS I with a relapse during surveillance, six (10%) CS I with a relapse following adjuvant chemotherapy, and 23 (37%) initial CS IIA/B. Metastatic seminoma was verified in 58 patients (94%) with a median largest diameter of 18 mm (interquartile range [IQR] 13-24). Robot-assisted RPLND was performed in 40 patients (65%). Clavien-Dindo III complications were observed in three patients (5%); no grade ≥IV complications occurred. Eighteen patients (29%) received adjuvant chemotherapy after surgery. The median follow-up was 23 mo (IQR 16-30), and recurrence occurred in six patients (10%) after a median of 8 mo (IQR 4-14). PFS was 90% (95% confidence interval: 0.86-1) and OS was 100% at 24 mo. Conclusions and clinical implications: RPLND as primary treatment is an option for selected low-stage seminomas with a limited burden of disease, showing low complications and low relapse rates, with the potential to reduce long-term morbidity. Patient summary: In seminoma patients with limited metastatic spread, surgery is a treatment option offering an alternative to chemotherapy or radiation. This paper covers the first 62 patients operated in Norway and Sweden.

7.
J Genet Genomics ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38969260

RESUMO

The specification of germ cells in zebrafish mostly relies on an inherited mechanism by which localized maternal determinants, called germ plasm, confer germline fate in the early embryo. Extensive studies have partially allowed the identification of key regulators governing germ plasm formation and subsequent germ cell development. RNA-binding proteins, acting in concert with other germ plasm components, play essential roles in the organization of the germ plasm and the specification, migration, maintenance, and differentiation of primordial germ cells. The loss of their functions impairs germ cell formation and causes sterility or sexual conversion. Evidence is emerging that they instruct germline development through differential regulation of mRNA fates in somatic and germ cells. However, the challenge remains to decipher the complex interplay of maternal germ plasm components in germ plasm compartmentalization and germ cell specification. Since failure to control the developmental outcome of germ cells disrupts the formation of gametes, it is important to gain a complete picture of regulatory mechanisms operating in the germ cell lineage. This review sheds light on the contributions of RNA-binding proteins to germ cell development in zebrafish and highlights intriguing questions that remain open for future investigation.

8.
Poult Sci ; 103(9): 103977, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38970845

RESUMO

Chicken embryos serve as an important model for investigating germ cells due to their ease of accessibility and manipulation within the egg. Understanding the development of germ cells is particularly crucial, as they are the only cell types capable of transmitting genetic information to the next generation. Therefore, gene expression regulation in germ cells is important for genomic function. Epigenetic programming is a crucial biological process for the regulation of gene expression without altering the genome sequence. Although epigenetic programming is evolutionarily conserved, several differences between chickens and mammals have been revealed. In this review, we compared the epigenetic regulation of germ cells in chickens and mammals (mainly mice as a representative species). In mammals, migrating primordial germ cells (precursors for germ cells [PGCs]) undergo global DNA demethylation and persist until sexual differentiation, while in chickens, DNA is demethylated until reaching the gonad but remethylated when sexually differentiated. Prospermatogonia is methylated at the onset of mitotic arrest in mammals, while DNA is demethylated at mitotic arrest in chickens. Furthermore, genomic imprinting and inactivation of sex chromosomes are differentially regulated through DNA methylation in chickens and mammals. Chickens and mammals exhibit different patterns of histone modifications during germ cell development, and non-coding RNA, which is not involved in PGC differentiation in mice, plays an important role in chicken PGC development. Additionally, several chicken-specific non-coding RNAs have been identified. In conclusion, we summarized current knowledge of epigenetic gene regulation of chicken germ cells, comparing that of mammals, and highlighted notable differences between them.

9.
Cell Regen ; 13(1): 13, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38918264

RESUMO

F-box proteins play essential roles in various cellular processes of spermatogenesis by means of ubiquitylation and subsequent target protein degradation. They are the substrate-recognition subunits of SKP1-cullin 1-F-box protein (SCF) E3 ligase complexes. Dysregulation of F­box protein­mediated proteolysis could lead to male infertility in humans and mice. The emerging studies revealed the physiological function, pathological evidence, and biochemical substrates of F-box proteins in the development of male germ cells, which urging us to review the current understanding of how F­box proteins contribute to spermatogenesis. More functional and mechanistic study will be helpful to define the roles of F-box protein in spermatogenesis, which will pave the way for the logical design of F-box protein-targeted diagnosis and therapies for male infertility, as the spermatogenic role of many F-box proteins remains elusive.

10.
J Med Microbiol ; 73(6)2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38922673

RESUMO

Introduction. Fluoroquinolone prophylaxis during haematopoietic cell transplantation (HCT) can lead to antimicrobial resistance (AMR). Identifying the groups of patients that have the highest likelihood of benefiting from prophylactic antimicrobials is important for antimicrobial stewardship (AMS).Hypothesis. We aimed to identify groups of HCT recipients that have the highest likelihood of benefiting from prophylactic fluroquinolones.Methods. All admissions for HCT in a tertiary centre between January 2020 and December 2022 (N = 400) were retrospectively studied. Allogeneic HCT (allo-HCT) recipients had prophylaxis with ciprofloxacin during the chemotherapy-induced neutropenia, while autologous HCT (auto-HCT) recipients did not. Bacteraemias were recorded when non-contaminant bacterial pathogens were isolated in blood cultures.Results. Allo-HCT was performed for 43.3 % (173/400) of patients and auto-HCT was performed for 56.7 % (227/400). A bacteraemia was documented in 28.3 % (113/400) of cases. Allo-HCT recipients were more likely to have a Gram-positive bacteraemia (20.8%, 36/173, vs 10.1%, 23/227, P = 0.03), while a difference was not observed for Gram-negative bacteraemias (18.5%, 32/173 vs 18.1%, 41/227, P = 0.91). Among auto-HCT recipients not receiving ciprofloxacin prophylaxis, patients with germ cell tumours had the highest probability (P for trend 0.09) of recording any bacteraemia (43.5%, 10/23) followed by patients with lymphomas (32.5%, 13/40), other auto-HCT indications (22.2%, 2/9), multiple myeloma (22.1%, 29/131) and multiple sclerosis (12.5%, 3/24). The higher number of bacteraemias in patients with germ cell tumours was primarily driven by Gram-negative pathogens.Conclusions. Ciprofloxacin prophylaxis was associated with a reduced incidence of Gram-negative bacteraemias in allo-HCT recipients. Auto-HCT recipients due to germ cell tumours, not receiving ciprofloxacin prophylaxis, recorded the highest incidence of bacteraemias and represent a possible target group for this intervention.


Assuntos
Antibacterianos , Antibioticoprofilaxia , Bacteriemia , Ciprofloxacina , Transplante de Células-Tronco Hematopoéticas , Neoplasias Embrionárias de Células Germinativas , Humanos , Ciprofloxacina/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Masculino , Estudos Retrospectivos , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Pessoa de Meia-Idade , Feminino , Adulto , Antibioticoprofilaxia/métodos , Antibacterianos/uso terapêutico , Bacteriemia/prevenção & controle , Bacteriemia/microbiologia , Idoso , Adulto Jovem , Neutropenia/complicações , Gestão de Antimicrobianos , Adolescente
11.
Pediatr Blood Cancer ; 71(8): e31126, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38837659

RESUMO

INTRODUCTION: Patients affected by metastatic germ cell tumors may occasionally experience enlargement of masses with concurrent normalization of tumor markers during or after chemotherapy. This phenomenon is described as growing teratoma syndrome (GTS). The aim of the pre sent study is to assess the prevalence of GTS in the pediatric population and its implications in terms of surgical outcome. PATIENTS AND METHODS: The clinical notes of patients diagnosed with stage III and IV malignant germ cell tumors from January 2010 until December 2020 at our Institution were retrospectively reviewed. The prevalence of GTS, treatment strategies, survival, and outcome were analyzed. RESULTS: Thirty-three patients with high-stage malignant germ cell tumors were diagnosed in our institution in the analyzed period. Nine patients (28%) had radiologic evidence of enlargement of persistent masses with normal markers after chemotherapy; these patients were classified as GTS patients. All nine patients underwent resection of metastatic lymph nodes, and six had surgery on visceral metastases. In six patients, radical excision of all metastatic sites was achieved; five patients are alive and in complete remission, while one died because of peri-operative complications. Out of the three patients who could not achieve radical excision of the metastases, two died of progressive disease, and one is alive with progressive disease. CONCLUSIONS: Patients affected by GTS have a risk of progression of chemotherapy-resistant disease and death. Radical surgical excision is essential to achieve disease control and long-term survival.


Assuntos
Teratoma , Humanos , Teratoma/cirurgia , Teratoma/patologia , Teratoma/epidemiologia , Teratoma/mortalidade , Teratoma/tratamento farmacológico , Masculino , Adolescente , Criança , Estudos Retrospectivos , Prevalência , Feminino , Prognóstico , Taxa de Sobrevida , Pré-Escolar , Seguimentos , Síndrome , Neoplasias Testiculares/cirurgia , Neoplasias Testiculares/patologia , Neoplasias Testiculares/epidemiologia , Neoplasias Testiculares/mortalidade
12.
Front Cell Dev Biol ; 12: 1410177, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38911025

RESUMO

Mammalian germ cells are derived from primordial germ cells (PGCs) and ensure species continuity through generations. Unlike irreversible committed mature germ cells, migratory PGCs exhibit a latent pluripotency characterized by the ability to derive embryonic germ cells (EGCs) and form teratoma. Here, we show that inhibition of p38 mitogen-activated protein kinase (MAPK) by chemical compounds in mouse migratory PGCs enables derivation of chemically induced Embryonic Germ-like Cells (cEGLCs) that do not require conventional growth factors like LIF and FGF2/Activin-A, and possess unique naïve pluripotent-like characteristics with epiblast features and chimera formation potential. Furthermore, cEGLCs are regulated by a unique PI3K-Akt signaling pathway, distinct from conventional naïve pluripotent stem cells described previously. Consistent with this notion, we show by performing ex vivo analysis that inhibition of p38 MAPK in organ culture supports the survival and proliferation of PGCs and also potentially reprograms PGCs to acquire indefinite proliferative capabilities, marking these cells as putative teratoma-producing cells. These findings highlight the utility of our ex vivo model in mimicking in vivo teratoma formation, thereby providing valuable insights into the cellular mechanisms underlying tumorigenesis. Taken together, our research underscores a key role of p38 MAPK in germ cell development, maintaining proper cell fate by preventing unscheduled pluripotency and teratoma formation with a balance between proliferation and differentiation.

13.
Gen Comp Endocrinol ; 356: 114576, 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38917936

RESUMO

Recombinant gonadotropins, follicle stimulating (rFsh) and luteinizing hormone (rLh), offer the potential to induce gametogenesis in prepubertal fish. This study aimed to determine the in vivo effect of the administration of Argyrosomus regius rFsh and rLh on the reproductive development of prepubertal meagre juveniles at the initial stages of sexual differentiation. Juvenile meagre, 9-months old with mean weight of 219 ± 3.9 g (mean ± SEM) were randomly distributed into nine groups (n = 8 per group). Experimental groups were treated weekly with an acute injection of either rFsh or rLh. Control groups were injected with saline solution. In a 3-week experiment, different groups were administered with different doses 6, 12 or 18 µg kg-1 of rFsh or rLh or saline solution. In a 6-week experiment a group was administered with 12 µg kg-1 of rFsh and a second group with saline solution. The fish were held in a single 10 m3 tank with natural photoperiod (Feb. - March) and temperature 16.1 ± 0.4 °C. At the start of the experiment (n = 8) and at the end of the 3-week experiment, fish were blood sampled and sacrificed. Blood was analysed for 17ß-estradiol (E2) and 11-ketotestosterone (11-KT). Gonads and liver were dissected and weighed. Gonads were fixed in Bouins solution and processed for histological analysis. Juvenile meagre at the start of the experiment were in the initial stages of sexual differentiation, indicated by the presence of the ovarian cavity or testes duct that was surrounded by undifferentiated embryonic germ stem cells and somatic cells. At the end of the 3-week experiment, there was no significant difference in gonadosomatic index (GSI) amongst control (initial and saline treated) and the experimental groups. After three weeks of application of rFsh, rLh or saline all fish presented a similar gonadal structure as at the start of the experiment. However, the incidence of sporadic developing germ cells (principally spermatogonia, spermatocytes, spermatids, but also perinucleolar stage oocytes) generally increased in rGth treated meagre. A mean of 44 % of meagre treated with rFsh or rLh presented sporadic isolated developing germ cells, mainly male cells. Plasma steroid levels of E2 decreased significantly from the start of the experiments to the end. At the end of the experiments there were no differences in plasma E2 amongst Control fish and rGth treated fish. Plasma 11-KT showed no change from the start of the experiment to week 3. However, a significant increase was observed in a proportion of the rFsh group after six weeks of treatment compared to the start of the experiment and the saline control group on week 6. The application of rFsh or rLh to meagre at the initial stages of sex differentiation did not stimulate steroid production until week six (11-KT) and had a limited, but evident effect on the development of sporadic isolated germ cells. However, we conclude that rGth, rFsh or rLh did not stimulate large developmental changes in sexually undifferentiated meagre gonads.

14.
Development ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884383

RESUMO

The specialized cell cycle of meiosis transforms diploid germ cells into haploid gametes. In mammals, diploid spermatogenic cells acquire the competence to initiate meiosis in response to retinoic acid. Previous mouse studies revealed that MEIOC interacts with RNA-binding proteins YTHDC2 and RBM46 to repress mitotic genes and promote robust meiotic gene expression in spermatogenic cells that have initiated meiosis. Here, we used the enhanced resolution of scRNA-seq, and bulk RNA-seq of developmentally synchronized spermatogenesis, to define how MEIOC molecularly supports early meiosis in spermatogenic cells. We demonstrate that MEIOC mediates transcriptomic changes before meiotic initiation, earlier than previously appreciated. MEIOC, acting with YTHDC2 and RBM46, destabilizes its mRNA targets, including transcriptional repressors E2f6 and Mga, in mitotic spermatogonia. MEIOC thereby derepresses E2F6- and MGA-repressed genes, including Meiosin and other meiosis-associated genes. This confers on spermatogenic cells the molecular competence to, in response to retinoic acid, fully activate transcriptional regulator STRA8-MEIOSIN, required for the meiotic G1/S phase transition and meiotic gene expression. We conclude that in mice, mRNA decay mediated by MEIOC-YTHDC2-RBM46 enhances the competence of spermatogenic cells to initiate meiosis.

15.
Proc Natl Acad Sci U S A ; 121(26): e2321349121, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38889152

RESUMO

Germ cells are regulated by local microenvironments (niches), which secrete instructive cues. Conserved developmental signaling molecules act as niche-derived regulatory factors, yet other types of niche signals remain to be identified. Single-cell RNA-sequencing of sexual planarians revealed niche cells expressing a nonribosomal peptide synthetase (nrps). Inhibiting nrps led to loss of female reproductive organs and testis hyperplasia. Mass spectrometry detected the dipeptide ß-alanyl-tryptamine (BATT), which is associated with reproductive system development and requires nrps and a monoamine-transmitter-synthetic enzyme Aromatic L-amino acid decarboxylase (AADC) for its production. Exogenous BATT rescued the reproductive defects after nrps or aadc inhibition, restoring fertility. Thus, a nonribosomal, monoamine-derived peptide provided by niche cells acts as a critical signal to trigger planarian reproductive development. These findings reveal an unexpected function for monoamines in niche-germ cell signaling. Furthermore, given the recently reported role for BATT as a male-derived factor required for reproductive maturation of female schistosomes, these results have important implications for the evolution of parasitic flatworms and suggest a potential role for nonribosomal peptides as signaling molecules in other organisms.


Assuntos
Planárias , Animais , Planárias/metabolismo , Feminino , Masculino , Peptídeo Sintases/metabolismo , Peptídeo Sintases/genética , Desenvolvimento Sexual , Peptídeos/metabolismo , Reprodução/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
16.
Front Oncol ; 14: 1360158, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38835384

RESUMO

Mixed germ cell tumors (mGCTs) involving both the ovaries and sellar region have been rarely reported; thus, they pose significant challenges in clinical management. Our report of a case of a 26-year-old female with left ovarian mGCTs (dysgerminoma + yolk sac tumor) who presented with postoperative headaches and blurred vision contributes new information to the literature on treating mGCTs, which can lead to standardized regimens and sequencing guidelines. A physical examination revealed right temporal hemianopia, and elevated levels of alpha-fetoprotein were detected in serum and cerebrospinal fluid. Magnetic resonance imaging (MRI) of the sellar region revealed a space-occupying lesion. Pathological examination of the tumor after endoscopic transnasal resection confirmed the diagnosis of mGCTs (germinomas + yolk sac tumor). The patient received adjuvant chemotherapy and radiotherapy at reduced dosages. During follow-up, tumor markers remained within normal limits, and there was no evidence of tumor recurrence on sellar region MRI. This case highlights the rarity of the simultaneous occurrence of ovarian and sellar region mGCTs and emphasizes the importance of accurate diagnosis and multidisciplinary management.

17.
Zygote ; : 1-6, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38828560

RESUMO

Spermatogenesis is a highly complex process through which mature sperms are produced, and it requires three important stages; mitosis, meiosis and sperm formation. The expression of genes regulated by transcription factors at specific stages exerts important regulatory effects on the development process of germ cells. Male mice with overexpressed programmed death ligand 1 (PD-L1) (B7 homolog1) in the testis have infertility and abnormal sperm development, thereby exhibiting severe malformation and sloughing throughout spermatid maturation and collapsed and disorganized seminiferous epithelium structure. Furthermore, PD-L1 overexpression causes overexpression of cysteine-rich secretory protein 1 (CRISP1) in the epididymis and adversely affects or precludes sperm energization, sperm-pellucida binding and sperm-oocyte fusion. These findings suggest that CRISP1 and PD-L1 can interact with each other to induce male infertility and germ-cell dissociation.

18.
Urol Case Rep ; 55: 102760, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38841430

RESUMO

Although germ cell tumours can appear in childhood, they are most common around the age of 30. These tumours are highly responsive to chemotherapy, and even cases of relapse have relatively high cure rates. There is limited literature on patients diagnosed after the age of 50, and no specific trials have been carried out in this context. These patients, considered 'elderly', are treated with the same cisplatin-containing combinations as younger patients, despite the higher toxicity. This report presents an observation of a giant testicular mixed germ cell tumour discovered in a 75-year-old patient.

19.
Toxicol Res (Camb) ; 13(2): tfae082, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38841432

RESUMO

Introduction: Cadmium (Cd) has been shown to disrupt the reproductive system. In this study, we evaluated the protective effects of Curcumin (Cur) against Cd-induced reproductive toxicity. Methods: Exploring the role of Cur in Cd-treated rat models. Results: The study demonstrated that Cd treatment impaired the seminiferous epithelium, leading to increased apoptosis of germ cells. Interestingly, pretreatment with Cur ameliorated the histological damage and decreased the germ cell apoptosis induced by Cd. Furthermore, after Cd exposure, B-cell lymphoma-2 expression was significantly decreased while Bax expression was increased. Pretreatment of rats with Cur protected against germ cell apoptosis by improving the expression of B-cell lymphoma-2 and reducing Bax. Additionally, Cd treatment increased reactive oxygen species, resulting in a decrease in antioxidant enzymes. However, pretreatment of rats with Cur followed by Cd administration led to a substantial decrease in reactive oxygen species levels and increased activities of antioxidant enzymes. Ultrastructural investigations revealed that damage to the mitochondrial structure was significantly ameliorated by Cur pretreatment in Cd-treated rats. Notably, Cur significantly activated the peroxisome proliferator-activated receptor gamma coactivator 1a/Sirtuins-3 signaling pathway. Conclusions: Overall, our data suggest that Cd induces germ cell apoptosis through mitochondrial-induced oxidative stress, but Cur pretreatment offers strong protection against Cd-induced reproductive toxicity.

20.
Neuroradiology ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38844695

RESUMO

PURPOSE: Malignant intracranial germ cell tumors (GCTs) are rare diseases in Western countries. They arise in midline structures and diagnosis is often delayed. We evaluated imaging characteristics and early tumor signs of suprasellar and bifocal GCT on MRI. METHODS: Patients with the diagnosis of a germinoma or non-germinomatous GCT (NGGCT) who received non-contrast sagittal T1WI on MRI pre-therapy were included. Loss of the posterior pituitary bright spot (PPBS), the expansion and size of the tumor, and the expansion and infiltration of surrounding structures were evaluated. Group comparison for histologies and localizations was performed. RESULTS: A total of 102 GCT patients (median age at diagnosis 12.3 years, range 4.4-33.8; 57 males; 67 in suprasellar localization) were enrolled in the study. In the suprasellar cohort, NGGCTs (n = 20) were noticeably larger than germinomas (n = 47; p < .001). Each tumor showed involvement of the posterior lobe or pituitary stalk. A PPBS loss (total n = 98) was observed for each localization and entity in more than 90% and was related to diabetes insipidus. Osseous infiltration was observed exclusively in suprasellar GCT (significantly more frequent in NGGCT; p = .004). Time between the first MRI and therapy start was significantly longer in the suprasellar cohort (p = .005), with an even greater delay in germinoma compared to NGGCT (p = .002). The longest interval to treatment had circumscribed suprasellar germinomas (median 312 days). CONCLUSION: A loss of the PPBS is a hint of tumor origin revealing small tumors in the neurohypophysis. Using this sign in children with diabetes insipidus avoids a delay in diagnosis.

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