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BACKGROUND: The unmet challenge in prostate cancer (PCa) management is to discriminate it from benign prostate hyperplasia (BPH) due to the lack of specific diagnostic biomarkers. Contemporary research on potential PCa biomarkers is directed toward methylated cell-free DNA (cfDNA) from liquid biopsies since epigenetic mechanisms are strongly involved in PCa development. METHODS: In the present research, cfDNA methylation of the LGALS3 gene in blood and seminal plasma of PCa and BPH patients was assessed using pyrosequencing, as well as LGALS3 DNA methylation in tissue biopsies. Liquid biopsy samples were taken from patients with clinical suspicion of PCa, who were subsequently divided into two groups, that is, 42 with PCa and 55 with BPH, according to the histopathological analysis. RESULTS: Statistically significant higher cfDNA methylation of LGALS3 in seminal plasma of BPH than in PCa patients was detected by pyrosequencing. ROC curve analysis showed that it could distinguish PCa and BPH patients with 56.4% sensitivity and 70.4% specificity, while PSA did not differ between the two patient groups. In contrast, there was no statistically significant difference in LGALS3 cfDNA methylation in blood plasma between the two patient groups. In prostate tumor tissue, there was a statistically significant DNA hypermethylation of LGALS3 compared to surrounding nontumor tissue and BPH tissue. CONCLUSIONS: The DNA hypermethylation of the LGALS3 gene represents an event specific to PCa development. In conclusion, LGALS3 cfDNA methylation in seminal fluid discriminates early PCa and BPH presenting itself as a powerful novel PCa biomarker highly outperforming PSA.
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Biomarcadores Tumorais , Metilação de DNA , Antígeno Prostático Específico , Hiperplasia Prostática , Neoplasias da Próstata , Sêmen , Humanos , Masculino , Neoplasias da Próstata/genética , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/sangue , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/sangue , Idoso , Antígeno Prostático Específico/sangue , Antígeno Prostático Específico/genética , Hiperplasia Prostática/genética , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/metabolismo , Hiperplasia Prostática/sangue , Hiperplasia Prostática/patologia , Sêmen/metabolismo , Sêmen/química , Pessoa de Meia-Idade , Ácidos Nucleicos Livres/genética , Ácidos Nucleicos Livres/sangue , Galectina 3/genética , Galectina 3/metabolismo , Galectina 3/sangue , Sensibilidade e Especificidade , Proteínas Sanguíneas , GalectinasRESUMO
Mast cells (MCs) are an evolutionary well-conserved type of cells, mediating and modulating allergic responses in innate immunity and tissue remodeling after chronic inflammation. Among other tissues, they inhabit both the testis and epididymis. In the testis, MCs usually appear in the interstitial compartment in humans, but not in other standard experimental models, like rats and mice. MCs seem to be responsible for testicular tissue fibrosis in different causes of infertility. Although experimental animal models follow the effect on MC activation or penetration to the interstitial tissue like in humans to some extent, there is an inconsistency in the available literature regarding experimental design, animal strain, and detection methods used. This comprehensive review offers an insight into the literature on MCs in mammalian testes and epididymides. We aimed to find the most suitable model for research on MC and offer recommendations for future experimental designs. When using in vivo animal models, tunica albuginea incorporation and standard histological assessment need to be included. Domesticated boar strains kept in modified controlled conditions exhibit the highest similarity to the MC distribution in the human testis. 3D testicular models are promising but need further fine-tuning to become a valid model for MC investigation.
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Epididimo , Testículo , Animais , Humanos , Masculino , Mamíferos , Mastócitos , Camundongos , Modelos Animais , Ratos , SuínosRESUMO
The teratogenic activity of valproate (VPA), an antiepileptic and an inhibitor of histone deacetylase (HDACi), is dose-dependent in humans. Previous results showed that VPA impairs in vitro development and neural differentiation of the gastrulating embryo proper. We aimed to investigate the impact of a lower VPA dose in vitro and whether this effect is retained in transplants in vivo. Rat embryos proper (E9.5) and ectoplacental cones were separately cultivated at the air-liquid interface with or without 1 mM VPA. Embryos were additionally cultivated with HDACi Trichostatin A (TSA), while some cultures were syngeneically transplanted under the kidney capsule for 14 days. Embryos were subjected to routine histology, immunohistochemistry, Western blotting and pyrosequencing. The overall growth of VPA-treated embryos in vitro was significantly impaired. However, no differences in the apoptosis or proliferation index were found. Incidence of the neural tissue was lower in VPA-treated embryos than in controls. TSA also impaired growth and neural differentiation in vitro. VPA-treated embryos and their subsequent transplants expressed a marker of undifferentiated neural cells compared to controls where neural differentiation markers were expressed. VPA increased the acetylation of histones. Our results point to gastrulation as a sensitive period for neurodevelopmental impairment caused by VPA.
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Inibidores de Histona Desacetilases , Ácido Valproico , Acetilação , Animais , Feminino , Gastrulação , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Humanos , Mamíferos/metabolismo , Placenta/metabolismo , Gravidez , Ratos , Ácido Valproico/farmacologiaRESUMO
Antioxidant N-tert-Butyl-α-phenylnitron (PBN) partly protected embryos from the negative effects of a DNA demethylating drug 5-azacytidine during pregnancy. Our aim was to investigate PBN's impact on the placenta. Fischer rat dams were treated on gestation days (GD) 12 and 13 by PBN (40 mg/kg), followed by 5azaC (5 mg/kg) after one hour. Global methylation was assessed by pyrosequencing. Numerical density was calculated from immunohistochemical expression in single cells for proliferating (PCNA), oxidative (oxoguanosine) and nitrosative (nitrotyrosine) activity. Results were compared with the PBN-treated and control rats. PBN-pretreatment significantly increased placental weight at GD15 and GD20, diminished by 5azaC, and diminished apoptosis in GD 20 placentas caused by 5azaC. Oxoguanosine expression in placentas of 5azaC-treated dams was especially high in the placental labyrinth on GD 15, while PBN-pretreatment lowered its expression on GD 15 and GD 20 in both the labyrinth and basal layer. 5azaC enhanced nitrotyrosine level in the labyrinth of both gestational stages, while PBN-pretreatment lowered it. We conclude that PBN exerted its prophylactic activity against DNA hypomethylating agent 5azaC in the placenta through free radical scavenging, especially in the labyrinthine part of the placenta until the last day of pregnancy.
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Azacitidina/toxicidade , Óxidos N-Cíclicos/farmacologia , Metilação de DNA/efeitos dos fármacos , Estresse Oxidativo , Placenta/patologia , 8-Hidroxi-2'-Desoxiguanosina/metabolismo , Animais , Biomarcadores/metabolismo , Proliferação de Células/efeitos dos fármacos , Feminino , Nitrosação/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Placenta/efeitos dos fármacos , Gravidez , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos Endogâmicos F344 , Tirosina/análogos & derivados , Tirosina/metabolismoRESUMO
We screened for the impact of hyperthermal regimes varying in the cumulative equivalent minutes at 43°C (CEM43°C) and media composition on tumour development using an original teratoma in vitro model. Rat embryos (three germ layers) were microsurgically isolated and cultivated at the air-liquid interface. During a two week period, ectodermal, mesodermal and endodermal derivatives developed within trilaminar teratomas. Controls were grown at 37°C. Overall growth was measured, and teratoma survival and differentiation were histologically assessed. Cell proliferation was stereologically quantified by the volume density of Proliferating Cell Nuclear Antigen. Hyperthermia of 42°C, applied for 15 minutes after plating (CEM43°C 3.75 minutes), diminished cell proliferation (P Ë .0001) and enhanced differentiation of both myotubes (P Ë .01) and cylindrical epithelium (P Ë .05). Hyperthermia of 43°C applied each day for 30 minutes during the first week (CEM43°C 210 minutes) impaired overall growth (P Ë .01) and diminished cell proliferation (P Ë .0001). Long-term hyperthermia of 40.5°C applied for two weeks (CEM43°C 630 minutes) significantly impaired survival (P Ë .005). Long-term hyperthermia of 40.5°C applied from the second day when differentiation of tissues begins (CEM43°C 585 minutes) impaired survival (P Ë .0001), overall growth (P Ë .01) and cartilage differentiation (P Ë .05). No teratomas survived extreme regimes: 43°C for 24 hours (CEM43°C 1440 minutes), hyperthermia in the scant serum-free medium (CEM43°C 630 minutes) or treatment with an anti-HSP70 antibody before long-term hyperthermia 40.5°C from the second day (CEM43°C 585 minutes). This in vitro research provided novel insights into the impact of hyperthermia on the development of experimental teratomas from their undifferentiated sources and are thus of potential interest for future therapeutic strategies in corresponding in vivo models.
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Embrião de Mamíferos/patologia , Hipertermia Induzida/métodos , Teratoma/patologia , Teratoma/prevenção & controle , Animais , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Técnicas de Cultura Embrionária , Embrião de Mamíferos/metabolismo , Feminino , Gravidez , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos Endogâmicos F344 , Teratoma/metabolismo , Fatores de TempoRESUMO
BACKGROUND: Among malignant diseases which develop during childhood, hematological cancers, such as leukemias and lymphomas, are the most common. Outcomes have greatly improved due to the refinement of multiagent chemotherapy regimens that include enhanced asparaginase therapy. In this study, we aimed to evaluate our experiences related to the analytical and clinical significance of determining l-Asparaginase activity. METHODS: Since 2016, the Laboratory of the Children's Hospital Zagreb has routinely measured l-Asparaginase activity and to date, has measured more than 280 examples of activity in a total of 57 children with hematological malignancy treated at the Pediatric Oncology Department of the Children's Hospital Zagreb. Three asparaginase products were available: native E. colil-Asparaginase; a pegylated form of this enzyme; and a native product from Erwinia chrysanthemi. A retrospective data analysis was performed. RESULTS: Out of the fifty-seven children, seven had an allergic reaction (12.3%), five (8.8%) had silent inactivation, and seven (12.3%) developed acute pancreatitis. Allergic reactions and silent inactivation were more common in children treated with native E. colil-Asparaginase, while pancreatitis was more common in children treated with the pegylated form. CONCLUSIONS: The monitoring of l-Asparaginase activity may help to optimize therapy by identifying patients with 'silent inactivation', and/or by dose correction when l-Asparaginase activity is too high (slow elimination).
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Introduction: Androgens play a pivotal role in shaping male sexual characteristics, with testosterone being an essential hormone in orchestrating various developmental processes. Testosterone biosynthesis involves a series of enzymatic reactions, among which the 17ß-hydroxysteroid dehydrogenase type 3 (HSD17B3) holds significance. While its role in adult Leydig cells is well established, its localization and importance during the fetal period remain less known, especially in humans. This study aims to delineate the dynamics of HSD17B3 expression in human fetal testes to clarify the contribution of specific cell types to testosterone biosynthesis. Methods: Using immunofluorescence staining, we investigated the expression pattern of HSD17B3 in human fetal and adult testicular tissues. Results and discussion: The findings of this study revealed a distinct temporal and cellular expression pattern of HSD17B3 protein in the fetal period. We detected its expression exclusively in Sertoli cells, the highest during the second trimester. This unique localization suggests the inclusion of fetal Sertoli cells in testosterone production during the critical masculinization-programming window. Furthermore, we demonstrated a shift in HSD17B3 expression from Sertoli cells to Leydig cells in adulthood, corroborating findings from rodent studies. This study sheds light on the intricate, still underexplored regulation of steroidogenesis during fetal development, whose disturbance might lead to testicular dysgenesis. Further research is warranted to elucidate the regulatory pathways governing the expression of HSD17B3 and its transition between Sertoli and Leydig cells, potentially paving the way for novel therapeutic interventions in disorders of sexual development.
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The increase in cancer survival rates has put a focus on ensuring fertility preservation procedures for cancer patients. Ovarian tissue cryopreservation presents the only option for prepubertal girls and patients who require immediate start of treatment and, therefore, cannot undergo controlled ovarian stimulation. We aimed to provide an assessment of stem cells' impact on cryopreserved ovarian tissue grafts in regard to the expression of growth factors, angiogenesis promotion, tissue oxygenation, ovarian follicle survival and restoration of endocrine function. For this systematic review, we searched the Scopus and PubMed databases and included reports of trials using murine and/or human cryopreserved ovarian tissue for transplantation or in vitro culture in combination with mesenchymal stem cell administration to the grafting site. Of the 1201 articles identified, 10 met the criteria. The application of stem cells to the grafting site has been proven to support vascular promotion and thereby shorten the period of tissue hypoxia, which is reflected in the increased number of remaining viable follicles and faster recovery of ovarian endocrine function. Further research is needed before implementing the use of stem cells in OT cryopreservation and transplantation procedures in clinical practice. Complex ethical dilemmas make this process more difficult.
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Azoospermia is a form of male infertility characterized by a complete lack of spermatozoa in the ejaculate. Sertoli cell-only syndrome (SCOS) is the most severe form of azoospermia, where no germ cells are found in the tubules. Recently, FANCM gene variants were reported as novel genetic causes of spermatogenic failure. At the same time, FANCM variants are known to be associated with cancer predisposition. We performed whole-exome sequencing on a male patient diagnosed with SCOS and a healthy father. Two compound heterozygous missense mutations in the FANCM gene were found in the patient, both being inherited from his parents. After the infertility assessment, the patient was diagnosed with diffuse astrocytoma. Immunohistochemical analyses in the testicular and tumor tissues of the patient and adequate controls showed, for the first time, not only the existence of a cytoplasmic and not nuclear pattern of FANCM in astrocytoma but also in non-mitotic neurons. In the testicular tissue of the SCOS patient, cytoplasmic anti-FANCM staining intensity appeared lower than in the control. Our case report raises a novel possibility that the infertile carriers of FANCM gene missense variants could also be prone to cancer development.
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Astrocitoma , Mutação de Sentido Incorreto , Síndrome de Células de Sertoli , Humanos , Masculino , Astrocitoma/genética , Astrocitoma/patologia , Astrocitoma/diagnóstico , Síndrome de Células de Sertoli/genética , Síndrome de Células de Sertoli/patologia , Adulto , Sequenciamento do Exoma , DNA Helicases/genética , Azoospermia/genética , Azoospermia/patologia , Azoospermia/diagnósticoRESUMO
AIM: To establish an organotypic in vitro model of limb bud development to verify whether epigenetic drug and teratogen 5-azacytidine (5azaC) has an effect on limb buds independent of its effects on the placenta. METHODS: Fischer strain rat fore- and hindlimb buds were microsurgically isolated from 13 days old embryos and cultivated in vitro for two weeks at the air-liquid interface in Eagle's minimum essential medium (MEM) with 50% rat serum. 30 µmol of 5azaC was added to the fresh medium. Overall growth was measured by an ocular micrometer. Routine histology, immunohistochemical detection of the proliferating cell nuclear antigen (PCNA), and stereological quantification of PCNA expression were performed. RESULTS: At four time points, significantly lower overall growth was detected for fore- and hindlimb bud explants cultivated with 5azaC in comparison to controls. After the culture period, numerical density of the PCNA signal for both types of limb buds was lower than for controls (P<0.001). Limb buds were initially covered by immature epithelium and contained mesenchyme, myotubes, single hemangioblasts, hemangioblast aggregates, blood islands, and capillaries. Regardless of the treatment, cartilage and epidermis differentiated, but cells and structures typical for vasculogenesis disappeared. CONCLUSION: Our findings, obtained outside of the maternal organism, stress the importance of compromised cell proliferation for 5azaC impact on limb buds. This investigation points to the necessity to establish alternatives to in vivo research on animals using teratogenic agents.
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Azacitidina/farmacologia , Proliferação de Células/efeitos dos fármacos , Epigenômica , Botões de Extremidades/crescimento & desenvolvimento , Teratogênicos/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Feminino , Humanos , Botões de Extremidades/citologia , Botões de Extremidades/efeitos dos fármacos , Técnicas de Cultura de Órgãos , Gravidez , Antígeno Nuclear de Célula em Proliferação/análise , Ratos , Ratos Endogâmicos F344RESUMO
BACKGROUND: Methodological advancements, such as relative haplotype and relative mutation dosage analyses, have enabled non-invasive prenatal diagnosis of autosomal recessive and X-linked diseases. Duchenne muscular dystrophy (DMD) is an X-linked recessive disease characterized by progressive proximal muscular dystrophy and a high mortality rate before the age of twenty. We aimed to systematically present obtainable data regarding a non-invasive prenatal diagnosis of DMD and provide a comprehensive resume on the topic. The emphasis was given to the comparison of different available protocols and molecular methods used for fetal inheritance deduction, as well as their correlation with prognostic accuracy. METHODS: We searched the Scopus and PubMed databases on 11 November 2022 and included articles reporting a non-invasive prenatal diagnosis of DMD in families at risk using relative dosage analysis methods. RESULTS: Of the 342 articles identified, 7 met the criteria. The reported accuracy of NIPT for DMD was 100% in all of the studies except one, which demonstrated an accuracy of 86.67%. The combined accuracy for studies applying indirect RHDO, direct RHDO, and RMD approaches were 94.74%, 100%, and 100%, respectively. Confirmatory results by invasive testing were available in all the cases. Regardless of the technological complexity and low prevalence of the disease that reduces the opportunity for systematic research, the presented work demonstrates substantial accuracy of NIPT for DMD. CONCLUSIONS: Attempts for its implementation into everyday clinical practice raise many ethical and social concerns. It is essential to provide detailed guidelines and arrange genetic counseling in order to ensure the proper indications for testing and obtain informed parental consent.
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The utility of cell-free tumor deoxyribonucleic acid analysis is currently being evaluated in a wide range of clinical studies. The validity of cell-free tumor deoxyribonucleic acid analysis methods used for screening and detecting malignant diseases, monitoring the effectiveness of treatment and disease progression, and identifying potential relapse is tested. Molecular technologies used for cell-free tumor deoxyribonucleic acid analysis include targeted polymerase chain reaction assays and next-generation sequencing approaches along with newly introduced epigenetic analysis methods such as methylation-specific polymerase chain reaction. The aim of this review was to compare the methods, pitfalls, and advantages of tests developed for the analysis of cell-free tumor deoxyribonucleic acid in the diagnosis and treatment of pediatric solid tumors. For this purpose, the PubMed database was searched for articles published in the last 10 years, in English, that investigated a human cohort aged 0 to 18 years. A total of 272 references were analyzed. A total of 33 studies were included in the review. Cell-free tumor deoxyribonucleic acid analysis has emerged as a promising novel approach that could potentially bring a significant improvement in the field of pediatric oncology, but the implementation of cell-free tumor deoxyribonucleic acid in clinical practice is largely hindered by the lack of standardized methods for processing and analysis.
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Valid data on prenatal cell-free DNA-based screening tests for copy number variations and microdeletions are still insufficient. We aimed to compare different methodological approaches concerning the achieved diagnostic accuracy measurements and positive predictive values. For this systematic review, we searched the Scopus and PubMed databases and backward citations for studies published between 2013 and 4 February 2022 and included articles reporting the analytical and clinical performance of cfDNA screening tests for CNVs and microdeletions. Of the 1810 articles identified, 32 met the criteria. The reported sensitivity of the applied tests ranged from 20% to 100%, the specificity from 81.62% to 100%, and the PPV from 3% to 100% for cases with diagnostic or clinical follow-up information. No confirmatory analysis was available in the majority of cases with negative screening results, and, therefore, the NPVs could not be determined. NIPT for CNVs and microdeletions should be used with caution and any developments regarding new technologies should undergo strict evaluation before their implementation into clinical practice. Indications for testing should be in correlation with the application guidelines issued by international organizations in the field of prenatal diagnostics.
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Objective: Undescended testes (UDT) is the most common anomaly of the male genitourinary tract. The guidelines suggest that orchidopexy in congenitally UDT should be performed between 6 months and 18 months of age, while in acquired UDT, orchidopexy should be performed before puberty. Delay in treatment increases the risk of cancer and infertility. The main aim of this study was to determine whether we meet international standards in the treatment of UDT. Methods: The present study included all boys who underwent orchidopexy either due to congenital or acquired UDT in 2019 (from January 1 to December 31). For each group, laterality, location, associated anomalies, premature birth and in how many cases ultrasound was applied were determined. Additionally, for each group, the types of surgery, the number of necessary reoperations, and in how many cases atrophy occurred were determined. Finally, ages of referral, of clinical examination, and of orchidopexy were determined. Results: During this period, 198 patients with 263 UDT underwent orchidopexy. The median time of orchidopexy for the congenital group was 30 months, while that for the acquired group was 99 months. In the congenital group up to 18 months of age, orchidopexy was performed in 16 (16%) boys, while in the acquired group up to 13 years of age, orchidopexy was performed in 95 (96.94%) boys. Conclusion: Given the well-known risks of late treatment of UDT, orchidopexy needs to be performed much earlier, especially in the congenital group.
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BACKGROUND: Male infertility is caused by genetic anomalies in 15-30% of cases. This study aimed to determine stereological properties of seminiferous tubules in infertile men with genetic anomalies, including Klinefelter Syndrome (KS), Y chromosome microdeletions (MYC) and CFTR gene mutations (CFTR); and to compare them to seminiferous tubules of men with obstructive azoospermia of non-genetic origin (control group). METHODS: The study was conducted on 28 human testis biopsy specimens obtained from 14 patients with MYC, 18 samples from 9 patients with KS, and 6 samples from 3 patients with CFTR. Whenever possible, a bilateral biopsy was included in the study. The control group had 33 samples from 18 patients (3 of them with a solitary testis). Qualitative and quantitative (stereological) analysis of seminiferous tubules (including the status of spermatogenesis, volume, surface area, length and number of tubules) were performed in all groups. RESULTS: Qualitative histological analysis revealed significant impairment of spermatogenesis in KS and MYC, whereas testicular parenchyma was fully maintained in CFTR and control groups. Spermatogenesis was most seriously impaired in KS. All stereological parameters were significantly lower in KS and MYC, compared to the CFTR and control groups. The total volume, surface and length of seminiferous tubules were significantly lower in KS compared with MYC. CONCLUSIONS: Stereological analysis is valuable in evaluating male infertility, whereas qualitative histological analysis can be helpful in assessing sperm presence in testicular tissue of patients with KS or MYK undergoing TESE.
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Azoospermia , Infertilidade Masculina , Síndrome de Klinefelter , Azoospermia/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Humanos , Infertilidade Masculina/genética , Síndrome de Klinefelter/genética , Masculino , Túbulos Seminíferos/patologia , Testículo/patologiaRESUMO
Testicular torsion potentially leads to acute scrotum and testicle loss, and requires prompt surgical intervention to restore testicular blood flow, despite the paradoxical negative effect of reperfusion. While no drug is yet approved for this condition, antioxidants are promising candidates. This study aimed to determine astaxanthin's (ASX), a potent antioxidant, effect on rat testicular torsion-detorsion injury. Thirty-two prepubertal male Fischer rats were divided into four groups. Group 1 underwent sham surgery. In group 2, the right testis was twisted at 720° for 90 min. After 90 min of reperfusion, the testis was removed. ASX was administered intraperitoneally at the time of detorsion (group 3) and 45 min after detorsion (group 4). Quantification of caspase-3 positive cells and oxidative stress markers detection were determined immunohistochemically, while the malondialdehyde (MDA) value, superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities were determined by colorimetric assays. The number of apoptotic caspase-3 positive cells and the MDA value were lower in group 4 compared to group 2. A significant increase in the SOD and GPx activity was observed in group 4 compared to groups 2 and 3. We conclude that ASX has a favorable effect on testicular ischemia-reperfusion injury in rats.
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Cartilage differentiates in rat limb buds cultivated in a chemically defined protein-free medium in the same manner as in the richer serum-supplemented medium. We aimed to investigate the remaining differentiation potential of pre-cultivated limb buds by subsequent transplantation in vivo. Rat front (FLBs) and hind-limb buds (HLBs) were isolated from Fischer rat dams at the 14th gestation day (GD 14) and cultivated at the air-liquid interface in Eagle's Minimum Essential Medium (MEM) alone; with 5 µM of 5-azacytidine (5azaC) or with rat serum (1:1). Overall growth was measured seven times during the culture by an ocular micrometre. After 14 days, explants were transplanted under the kidney capsule of adult males. Growth of limb buds was significantly lower in all limb buds cultivated in MEM than in those cultivated with serum. In MEM with 5azaC, growth of LBs was significantly lower only on day 3 of culture. Afterwards, it was higher throughout the culture period, although a statistically significant difference was assessed only for HLBs. In transplants, mixed structures developed with the differentiated transmembranous bone, cartilage with enchondral ossification, bone-marrow, sebaceous gland, and hair that have never been found in vitro. Nerves differentiated only in transplants precultivated in the serum-supplemented medium. We conclude that pre-cultivation of LBs in a chemically defined protein-free medium does not restrict osteogenesis and formation of epidermal appendages but is restrictive for neural tissue. These results are important for understanding limb development and regenerative medicine strategies.
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Botões de Extremidades , Osteogênese , Animais , Azacitidina , Epiderme , Masculino , Ratos , Ratos Endogâmicos F344RESUMO
Although DNA methylation epigenetically regulates development, data on global DNA methylation during development of limb buds (LBs) are scarce. We aimed to investigate the global DNA methylation developmental dynamics in rat LBs cultivated in a serum-supplemented (SS) and in chemically defined serum- and protein-free (SF) three-dimensional organ culture. Fischer rat front- and hind-LBs at 13th and 14th gestation days (GD) were cultivated at the air-liquid interface in Eagle's Minimal Essential Medium (MEM) or MEM with 50% rat serum for 14 days, as SF and SS conditions, respectively. The methylation of repetitive DNA sequences (SINE rat ID elements) was assessed by pyrosequencing. Development was evaluated by light microscopy and extracellular matrix glycosaminoglycans staining by Safranin O. Upon isolation, weak Safranin O staining was present only in more developed GD14 front-LBs. Chondrogenesis proceeded well in all cultures towards day 14, except in the SF-cultivated GD13 hind-LBs, where Safranin O staining was almost absent on day 3. That was associated with a higher percentage of DNA methylation than in SF-cultivated GD13 front-LBs on day three. In SF-cultivated front-LBs, a significant methylation increase between the 3rd and 14th day was detected. In SS-cultivated GD13 front-LBs, methylation increased significantly on day three and then decreased. In older GD14 SS-cultivated LBs, there was no increase of DNA methylation, but they were significantly hypomethylated relative to the SS-cultivated GD13 at days 3 and 14. We confirmed that the global DNA methylation increase is associated with less developed limb organ primordia that strive towards differentiation in vitro, which is of importance for regenerative medicine strategies.
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Condrogênese , Botões de Extremidades , Animais , Diferenciação Celular , Metilação de DNA , Matriz Extracelular , Técnicas de Cultura de Órgãos , RatosRESUMO
RASSF1A, one of the eight isoforms of the RASSF1 gene, is a tumor suppressor gene that influences tumor initiation and development. In cancer, RASSF1A is frequently inactivated by mutations, loss of heterozygosity, and, most commonly, by promoter hypermethylation. Epigenetic inactivation of RASSF1A was detected in various cancer types and led to significant interest; current research on RASSF1A promoter methylation focuses on its roles as an epigenetic tumor biomarker. Typically, researchers analyzed genomic DNA (gDNA) to measure the amount of RASSF1A promoter methylation. Cell-free DNA (cfDNA) from liquid biopsies is a recent development showing promise as an early cancer diagnostic tool using biomarkers, such as RASSF1A. This review discusses the evidence on aberrantly methylated RASSF1A in gDNA and cfDNA from different cancer types and its utility for early cancer diagnosis, prognosis, and surveillance. We compared methylation frequencies of RASSF1A in gDNA and cfDNA in various cancer types. The weaknesses and strengths of these analyses are discussed. In conclusion, although the importance of RASSSF1A methylation to cancer has been established is included in several diagnostic panels, its diagnostic utility is still experimental.
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Biomarcadores Tumorais/genética , Neoplasias/genética , Proteínas Supressoras de Tumor/genética , Metilação de DNA , Epigenômica , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , HumanosRESUMO
Seminoma (SE) is the most frequent type of testicular tumour, affecting predominantly young men. Early detection and diagnosis of SE could significantly improve life quality and reproductive health after diagnosis and treatment. Copy number variation (CNV) has already been associated with various cancers as well as SE. In this study, we selected four genes (MAGEC2, NANOG, RASSF1A, and KITLG) for CNV analysis in genomic DNA (gDNA), which are located on chromosomes susceptible to gains, and whose aberrant expression was already detected in SE. Furthermore, CNV was analysed in cell-free DNA (cfDNA) from seminal plasma. Analysis was performed by droplet digital polymerase chain reaction (ddPCR) on gDNA from SE and nonmalignant testicular tissue. Seminal plasma cfDNA from SE patients before and after surgery was analysed, as well as from healthy volunteers. The CNV hotspot in gDNA from SE tissue was detected for the first time in all analysed genes, and for two genes, NANOG and KITLG it was reflected in cfDNA from seminal plasma. Although clinical value is yet to be determined, presented data emphasize a potential use of CNV as a potential SE biomarker from a liquid biopsy.