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Fluorescence in situ hybridization (FISH) has revolutionized molecular cytogenetic analysis since the 1980s, enabling precise localization of DNA sequences in cells and tissues. Despite its relevance, applying FISH to formalin-fixed paraffin-embedded (FFPE) tissue samples encounters significant technical challenges. This review addresses the main issues encountered in this context, such as inadequate fixation, contamination, block and slide age, inadequate pretreatment, and FISH technique. Proposed solutions include optimized pretreatment protocols, monitoring of blockage, careful selection of probes, and thorough analysis of results. Implementing good laboratory practices and quality control strategies are essential to ensure reliable results. Additionally, the use of emerging technologies such as artificial intelligence and digital pathology offers new perspectives for improving the efficiency and accuracy of FISH in FFPE samples. This review highlights the importance of a careful and personalized approach to overcome the technical challenges associated with FISH in FFPE samples, strengthening its role in research and clinical diagnosis. RESEARCH HIGHLIGHTS: Few FISH studies on FFPE: The scarcity of studies specifically addressing FISH applications in FFPE tissues highlights a critical gap in the literature. Troubleshooting FISH in FFPE tissues: Identifying and addressing common challenges in FISH techniques when applied to FFPE samples, such as signal quality and hybridization efficiency. Critical aspects of FISH technique: Discuss the main technical considerations crucial for successful FISH in FFPE tissues, including sample preparation, probe selection, and protocol optimization., (© 2024 Wiley Periodicals LLC.)

The beginning of post-mortem evaluation studies through minimally invasive procedures began between 1800 and 1930. It started with Dr. Howard Kelly and was later followed by Décio Parreiras and Werneck Genofre, due to the yellow fever outbreak in Brazil. However, despite its early beginnings, the intensification of the research on this field occurred around 2010, when the publications about this subject became three times more frequent than before. There are basically two classifications for this procedure. The first one is virtual non-invasive autopsy, which is based only on imaging exams; the second is the minimally invasive autopsy, in which imaging exams are associated with other techniques such as biopsy and angiography. The main objective of the present study is to evaluate the existent data published about virtual autopsy from 2010, and highlight the key concepts related to this theme. A search was conducted in PUBMED, MEDLINE, and LILACS databases using the descriptors "virtual autopsy" and "minimally invasive autopsy", the review protocol has been registered on Open Science Framework (OSF), the total number of studies included were 28, and the data was presented through the PRISMA-ScR flowchart. Although, it is well known that this theme is recent in research fields and, because of that, there is still a lot to explore., Competing Interests: Declaration of Competing Interest The authors declare no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (Copyright © 2024. Published by Elsevier GmbH.)

Purpose: To determine molecular events involved in the tumorigenesis of phyllodes tumors (PT) and the role of each stromal (SC) and epithelial (EC) cell., Methods: Frozen breast samples enriched with epithelial and stromal cells from three fibroadenomas and 14 PT were retrieved and laser microdissected. Sanger and polymerase chain reaction-based sequencing of exon 2 MED12 and TERT promoter hotspot mutations were performed; 44K microarray platform was used to analyze gene expression., Results: All three fibroadenomas (FAs) presented mutations in MED12, but not in TERT, whose mutation was observed in five of the 14 PTs. EC and SC of each affected tumor displayed identical alterations. Of the total differentially expressed genes (DEG) (EC = 1,543 and SC = 850), 984 were EC-eDEGs and 291 were SC-eDEGs. We found a high similarity of diseases and functions enriched by both cell types, but dissimilarity in the number of enriched canonical pathways. Three signaling canonical pathways overlapping with EC and SC were predicted to be activated in one cell type and inactivated in the other, while no overlap in eDEGs was assigned to them. We also identified 13 EC-eDEGs and five SC-eDEGs enriched networks, in which the SC-eDEGs were able to segregate FA from PT samples., Conclusions: Identical TERT mutations from both SC and ES origins might affect the PTs tumorigenesis. Gene expression differences suggest coordinated molecular processes between these components with determinant differences acquired by SC, able to fully distinguish PTs from FAs lesions.

Purpose: We evaluated the immunoexpression of potential markers involved in the HER2 pathway in invasive breast carcinoma with HER2 amplification treated with trastuzumab., Methods: Samples of ninety patients diagnosed and treated at two public Brazilian hospitals with overexpressed invasive carcinoma between 2009 and 2018 were included. Several markers (Bcl-2, CDK4, cyclin D1, EGFR, IGF1, IGF-1R, MDM2, MUC4, p16, p21, p27, p53, PTEN, RA, TNFα, and VEGF) were immune analyzed in the tumor by immunohistochemistry and then correlated with clinicopathological variables., Results: Tumor sample expression results determined potential markers of good prognosis with statistically significant values: cyclin D1 with a nuclear grade, and recurrence; IGF-1 with tumor size, and death; p16 with a response after treatment; PTEN with a response after treatment, and death. Markers of poor prognosis: p53 with histological, and nuclear grade; IGF-1R with a compromised lymph node. The treatment resistance rate after trastuzumab was 40%; the overall survival was 4.13 years (95% CI 5.1-12.5) and the disease-free survival was 3.6 years (95% CI 5.1-13.1)., Conclusions: The tumor samples profile demonstrated that cyclin D1, IGF-1, p16, and PTEN presented the potential for a good prognosis and p53 and IGF-1R for worse., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier GmbH. All rights reserved.)

Pilocytic astrocytoma is the most common primary CNS neoplasm in children and adolescents, rare after the first two decades of life. While some authors report a favorable prognosis in the adult age group with the tumor, others have associated it with higher mortality. The molecular alteration most observed in cases of pilocytic astrocytoma in the pediatric group is the BRAF-KIAA1549 gene fusion, and there are still few studies confirming the presence of this fusion in the adult population. This work investigated genetic alterations involving the 7q34 region in BRAF gene in 21 adult individuals with pilocytic astrocytoma, by FISH. In addition, was identified the immunohistochemical expression of BRAFV600E, correlating these findings with histopathological and clinical ones. BRAF-KIAA1549 fusion appeared in only one case, while in two other cases were found deletions related to the FAM131B-BRAF fusion, suggesting that maybe the latter is more frequently in this population. Through the evaluation of immunoreactivity, 71% of the cases were considered positive and 29% negative. Cases considered positive for BRAFV600E immunoreactivity can potentially be treated through drug therapy with BRAF inhibitors; however, it is always recommended to carry out a molecular study for diagnostic confirmation. This is the first Brazilian study that aimed to investigate possible genetic alterations in the BRAF gene in pilocytic astrocytomas, specifically in adults. Only 1 patient died, but due to operative complications and not the disease itself, suggesting a good evolution of these individuals., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Andrea Cristina de Moraes Malinverni reports financial support was provided by Coordination for the Improvement of Higher Education Personnel (CAPES) and São Paulo Research Foundation (FAPESP)., (Copyright © 2023 Elsevier GmbH. All rights reserved.)

Pilocytic astrocytoma is a central nervous system tumor of slow growth, which represents 5 % of all gliomas and most often develops in the cerebellum (42-60 %), but can also arise in other neural areas, such as the optic pathway or hypothalamus (9-30 %); brainstem (9 %); spinal cord (2 %). In the pediatric population, this tumor is the second most common cause of neoplasms and, on the other hand, in adults, it is often rare, probably due to its aggressiveness in these individuals. Studies reveal that the origin of pilocytic astrocytoma is characterized by a fusion between the BRAF gene and the KIAA1549 locus, and the application of the immunohistochemistry technique for the analysis of BRAF protein expression can be a valuable tool for diagnostic purposes. Due to the relative rarity of this disease in adults, there are few publications on the most effective diagnostic and treatment strategies for this tumor. The general objective of this study was to analyze the histopathological and immunohistochemical characteristics of pilocytic astrocytoma in these patients. For this, a retrospective study of patients aged over 17 years with a diagnosis of pilocytic astrocytoma was carried out at the Department of Pathology of UNIFESP/EPM, from 1991 to 2015. In order to define BRAF positivity in the immunohistochemical analysis, at least three consecutive fields with more than 50 % immunostaining were used as criteria and, thus, it was inferred that the 7 cases analyzed were considered positive for the cytoplasmic marker BRAF V600E. Histopathological analysis associated with BRAF immunostaining is of paramount importance as a diagnostic method in these cases. However, future molecular studies will be necessary both for a better understanding of the aggressiveness and prognostic of this tumor and for research involving specific therapies for pilocytic astrocytoma in adults., Competing Interests: Declaration of Competing Interest The authors declare no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (Copyright © 2023 Elsevier GmbH. All rights reserved.)

In the last decades, the micronucleus assay has been recognized as a suitable biomarker for monitoring populations exposed to many different occupational factors, lifestyle, environmental conditions, radiation exposure, and deleterious effects of pesticides. The objective of this work is to direct the design of future field studies in the assessment of the risk of children exposed to environmental mutagens, radiation, and pesticides. This review sought available information on the analysis of micronuclei in oral cells in children. A literature search for papers investigating DNA damage, genetic damage, oral cells, buccal cells, genotoxicity, mutagenicity and micronucleus was begun in 2000 and is scheduled to be concluded in May, 2022. Briefly, a search of PubMed, MEDLINE, and Google Scholar for a variety of articles was performed. The results showed that there are still few studies that addressed micronuclei of oral cells in children exposed to the most diverse environmental conditions. Only environmental pollution was associated with damage to the genome of oral cells in children. Therefore, researchers need to be calibrated in cell analysis, standardization of field study protocols and the development of new research in the evaluation of children using the micronucleus test as a tool in child biomonitoring., (© 2022 Walter de Gruyter GmbH, Berlin/Boston.)

Hydatidiform mole is an abnormal pregnancy in which two copies of paternal genetic material are present. Molar gestation is divided into complete and partial hydatidiform moles. Clinical, morphological, and cytogenetic characteristics are usually sufficient to distinguish them, but and the rare cases that are necessary to know the paternal origin to establish the diagnosis and segment? Mutations in the Gene for Factor V Leiden and G20210A prothrombin polymorphism in women with recurrent spontaneous abortion: a retrospective study in a Brazilian population., Competing Interests: Declaration of Conflicting Interest The authors declared no potential conflicts of interest concerning the research, authorship, and/or publication of this article., (Copyright © 2022 Elsevier GmbH. All rights reserved.)

Background/aim: The aim of this study was to investigate cytotoxicity, inflammatory response, and angiogenesis induced by silicone gel breast implants with different textured surfaces in vitro and in vivo., Materials and Methods: In the in vitro study, murine fibroblast cells (L929) were cultured for 1, 3, and 5 days with silicone membranes of three different textures: nanotextured, microtextured, and silicone foam. In the in vivo study, a total of 30 male rats (Rattus, norvegicus, albinos, Wistar) were distributed into three groups (10 animals per group), with 2 implants in each rat: nanotextured silicone gel breast implants group, microtextured silicone gel breast implants group, and silicone gel breast foam implants group., Results: The Alamar Blue assay detected higher viability of cells cultured in the presence of nanotextured silicone surface for 1 and 3 days. The MTT assay showed higher cytotoxicity of silicone foam after 1 and 3 days of exposure. Nanotextured silicone breast implants induced a more prolonged inflammatory response, denoting a delay in the healing process and subsequent organization of the fibrous capsule as depicted by the collagen fiber types found. VEGF expression did not differ between experimental groups., Conclusion: Gel foam breast implants are more biocompatible when compared to micro- or nano-textured silicone breast implants., (Copyright © 2022, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Pilocytic astrocytomas are the primary tumors most found in the first two decades of life, accounting for around 15% of all brain tumors. Research at the molecular level of pilocytic astrocytoma makes possible to compose an overview of what is known about the origin and development of the tumor. It is known that there are alterations in the Mitogen Activated Protein Kinase (MAPK) signaling pathway that are important auxiliary markers in diagnosis. This study seeks to list the main points about the involvement of this pathway in tumor formation in pilocytic astrocytoma. A review was conducted in search of published studies available in NCBI, PubMed, MEDLINE, Scielo and Google Scholar. The most frequent alteration is the gene fusion between BRAF and KIAA1549 genes, found in approximately 90% of pediatric cases. The second most common event is the BRAFV600E mutation, also often found in children than in adult cases. The molecular origin of pilocytic astrocytomas is related to alterations in the MAPK pathway, which acts with several functions in the brain such as memory formation, pain perception, induction of cortical neurogenesis, and midbrain and cerebellum development. Alterations in this pathway can be therapeutic targets in the treatment of patients with pilocytic astrocytoma. The MAPK pathway is extremely important and knowledge about its involvement in astrocytic tumors is essential for a better approach to the patient., (Copyright © 2022 Elsevier GmbH. All rights reserved.)

Background: Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system (CNS), which usually affects young adults between 20 and 40 years old. In chronic neurodegenerative diseases such as multiple sclerosis, CNS cells take on several adaptations during neuroinflammation. The main cells involved in this inflammatory process are the glial cells, in which the astrocytes stand out. These cells play a complex role, and several studies report that reactive astrocytes lose their supporting role and gain toxic function in the progression of these diseases., Results: The beneficial and injurious effects of this group of cells in MS are addressed in this work, as well as some drugs that are already used in the treatment of patients with multiple sclerosis, aiming to regulate astrocytic activities., Conclusions: The knowledge about the functions of astrocytes is essential for the expansion of scientific research in this area, since these cells are so important and involved in different mechanisms of action, especially in neurodegenerative and autoimmune diseases., (Copyright © 2022. Published by Elsevier B.V.)

Dimethoate ([O,O-dimethyl S-(N-methylcarbamoylmethyl) phosphorodithioate]) is an organophosphate insecticide and acaricide widely used for agricultural purposes. Genotoxicity refers to the ability of a chemical agent interact directly to DNA or act indirectly leading to DNA damage by affecting spindle apparatus or enzymes involved in DNA replication, thereby causing mutations. Taking into consideration the importance of genotoxicity induced by dimethoate, the purpose of this manuscript was to provide a mini review regarding genotoxicity induced by dimethoate as a result of oxidative stress. The present study was conducted on studies available in MEDLINE, PUBMED, EMBASE, and Google scholar for all kind of articles (all publications published until May, 2020) using the following key words: dimethoate, omethoate, DNA damage, genetic damage, oxidative stress, genotoxicity, mutation, and mutagenicity. The results showed that many studies were published in the scientific literature; the approach was clearly demonstrated in multiple tissues and organs, but few papers were designed in humans. In summary, new studies within the field are important for better understanding the pathobiological events of genotoxicity on human cells, particularly to explain what cells and/or tissues are more sensitive to genotoxic insult induced by dimethoate., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objectives: In this review, the main histological and molecular characteristics of meningiomas will be addressed, as well as the aspects most related to clinical conditions, treatment, and survival of patients, enabling a better understanding of these tumors behavior., Methods: This study was conducted with the search for published studies available on NCBI, PubMed, MEDLINE, Scielo and Google Scholar. Relevant documents have been identified and 50 articles were selected., Results: The main points about meningiomas were characterized, as well as the histological presence of spontaneous necrosis in grade I and brain invasion as diagnostic criteria, their molecular origin related to deletion of chromosome 22 and mutations in theNF2 and TERT genes, in addition to their clinical characteristics. The preferential treatment remains the total resection of the tumor., Conclusion: The information about meningiomas is well known and necessary, but it is expected that more work will emerge related to the behavior of these tumors, and that the scientific community will obtain more clarity about the best ways to conduct the patients treatment., (Copyright © 2021 Elsevier GmbH. All rights reserved.)

Pilocytic astrocytomas are the primary tumors most frequently found in children and adolescents, accounting for approximately 15.6% of all brain tumors and 5.4% of all gliomas. They are mostly found in infratentorial structures such as the cerebellum and in midline cerebral structures such as the optic nerve, hypothalamus, and brain stem. The present study aimed to list the main characteristics about this tumor, to better understand the diagnosis and treatment of these patients, and was conducted on search of the published studies available in NCBI, PubMed, MEDLINE, Scielo, and Google Scholar. It was possible to define the main histologic findings observed in these cases, such as mitoses, necrosis, and Rosenthal fibers. We described the locations usually most affected by tumor development, and this was associated with the most frequent clinical features. The comparison between the molecular diagnostic methods showed great use of fluorescent in situ hybridization, polymerase chain reaction (PCR), and reverse transcriptase-PCR, important techniques for the detection of BRAF V600E mutation and BRAF-KIAA1549 fusion, characteristic molecular alterations in pilocytic astrocytomas.

Background: It is believed that the Wnt pathway is one of the most important signaling involved in gastric carcinogenesis., Aim: To analyze the protein expression of canonical and non-canonical Wnt pathways in gastric carcinoma., Method: The immunohistochemistry was performed in 72 specimens of gastric carcinomas for evaluating the expression of Wnt-5a, FZD5, GSK3β, axin, CK1, ubiquitin, cyclin D1 and c-myc., Results: There were significant differences for cytoplasm and nucleus ubiquitin for moderately and well differentiated tumors (p=0.03) and for those of the intestinal type of the Lauren classification (p=0.03). The absence of c-myc was related to Lauren's intestinal tumors (p=0.03). Expression of CK1 in the cytoplasm was related to compromised margin (p=0.03). Expression of cyclin D1 protein was more intense in male patients (p=0.03) There was no relation of the positive or negative expression of the Wnt-5a, FZD5, GSK3 and Axin with any clinicopathological variables., Conclusion: The canonical WNT pathway is involved in gastric carcinoma.

Miller-Dieker syndrome (MDS) is a contiguous gene deletion syndrome in which almost all patients present de novo 17p13.3 deletions. We report on a male infant with MDS and an unusual unbalanced translocation involving chromosomes Y and 17 that resulted in a large 5.5-Mb 17pterp13.2 deletion and a karyotype with 45 chromosomes. Apart from the deletion of the MDS critical region, the deletion of additional distal genes seemed to have no major influence on the patient's phenotype, since he did not show any unusual clinical findings that are not commonly described in MDS patients., (© 2017 S. Karger AG, Basel.)

Partial monosomy 21 results in a great variability of clinical features that may be associated with the size and location of the deletion. In this study, we report a 22-month-old girl who showed a 45,XX,add(12)(p13)dn,-21 karyotype. The final cytogenomic result was 45,XX,der(12)t(12;21)(p13;q22.11) dn,-21.arr[hg19] 21q11.2q22.11(14824453_33868129)×1 revealing a deletion from 21pter to 21q22.11. Clinical manifestation of the patient included hypertonia, a long philtrum, epicanthic folds, low-set ears, and café-au-lait macules - a phenotype considered as mild despite the relatively large size of the deletion compared to patients from the literature., (© 2017 S. Karger AG, Basel.)