Myelin is an essential structure that facilitates rapid saltatory conduction in the nervous system. Discrepancies in myelin microstructure are a hallmark of numerous neurological disorders, rendering the assessment of myelin integrity and content an indispensable tool in clinical diagnostics and neuroscience research. Extensive research has been dedicated to scrutinizing its biochemical makeup and morphology under normal, pathological, and experimental conditions over the years. In this review, we present an updated summary of the myelin sheath's structure, composition, and developmental trajectory. We systematically enumerate and contrast eight prevalent myelin staining techniques across dimensions of sensitivity, specificity, and resolution, delving into their underlying staining principles. With an initial application of myelin histology on the mouse demyelination model, our review accentuates the accurate delineation of myelination and the microstructural analysis of the myelin sheath. Such insights are anticipated to significantly contribute to the evaluation and understanding of white matter pathologies.
Myelin Sheath/metabolism* ; Animals ; Humans ; Demyelinating Diseases/pathology* ; Staining and Labeling/methods*

Objective To summarize the clinicopathological features,immunohistochemical characteristics,HOX transcript antisense RNA(HOTAIR)in situ hybridization status,treatment,and prognosis of myxopapillary ependymoma(MPE). Methods A total of 17 patients diagnosed with MPE based on pathological evidence in the Department of Pathology of Peking Union Medical College Hospital from November 2006 to July 2023 were selected,and the clinicopathological data of these patients were collected.Immunohistochemical staining for trimethylation at lysine 27 of histone H3 (H3K27me3),glial fibrillary acidic protein(GFAP),and epithelial membrane antigen(EMA)and alcian blue-periodic acid Schiff(AB-PAS)staining were performed in all the patients.Sixteen patients with spinal ependymomas were selected as the control group.Tissue microarrays were prepared from 17 MPE patients and the control group.HOTAIR ISH was performed and semi-quantitatively scored,and the scores of the two groups were compared by the Wilcoxon rank-sum test. Results The 17 MPE patients aged 14-64 years,with the mean age of(37.48±16.10)years and the male-to-female ratio of 0.7∶1.Their clinical manifestations mainly included lumbosacral and lower limb pains.Microscopically,tumor cells were arranged in a papillary pattern around fibrovascular axis,with abundant myxoid materials,and tumor cells were arranged in a loose meshwork in some patients.The immunohistochemical staining results showed that 17(100%),10(58.82%),and 8(47.06%)patients expressed GFAP,EMA,and D2-40,respectively,and 2(11.76%)patients lacked expression of H3K27me3.AB-PAS staining showed blue myxoid materials in all the 17(100%)patients.HOTAIR was expressed in both MPE and control groups,with higher semi-quantitative score in the MPE group than in the control group(P=0.004).Twelve patients were followed up,with a median follow-up period of 65.50 months,during which three patients showed recurrence.Conclusions MPE exhibits typical pathological features,and the combination with immunohistochemical staining for GFAP and EMA as well as AB-PAS staining facilitates diagnosis of this disease.A small number of patients loss the expression of H3K27me3.HOTAIR is highly expressed in MPE but lacks specificity,which limits its auxiliary diagnostic value.The overall prognosis of MPE is favorable,with a few patients experiencing recurrence.
Humans ; Ependymoma/metabolism* ; Male ; Adult ; Female ; Adolescent ; Middle Aged ; In Situ Hybridization ; Young Adult ; RNA, Antisense/genetics* ; Immunohistochemistry ; Prognosis

Background and Objective: Retinoblastoma is one of the most common intraocular cancers among children usually caused by the loss of retinoblastoma protein function. Despite being a highly heritable disease, conventional diagnostic and prognostic methods depend on clinical examination, with limited consideration of cancer genetics in the standard of care. CD133, KRT19, and MUC1 are commonly explored genes for their utility in liquid biopsies of cancer including lung adenocarcinoma. To date, there are few extensive molecular studies on retinoblastoma in Filipino patients. To this end, the study aimed to describe the copy number of CD133, KRT19, and MUC1 in retinoblastoma samples from a Filipino patient and quantitate the respective expression level of these genes. Methods: Hematoxylin & Eosin (H&E) staining was utilized to characterize the retinoblastoma tissue while fluorescence in situ hybridization (FISH) using probes specific to CD133, KRT19, and MUC1 was performed to determine the copy number of genes in retinoblastoma samples from a Filipino patient (n = 1). The gene expression of CD133, MUC1, and KRT19 was quantitated using RT-qPCR. Results: The H&E staining in the retinoblastoma tissue shows poorly differentiated cells with prominent basophilic nuclei. CD133 was approximately 1.5-fold overexpressed in the retinoblastoma tissue with respect to the normal tissue, while MUC1 and KRT19 are only slightly expressed. Multiple intense signals of each probe were localized in the same nuclear areas throughout the retinoblastoma tissue, with high background noise. Conclusion These findings suggest that CD133 is a potential biomarker for the staging and diagnosis of retinoblastoma in Filipino cancer patients. However, further optimization of the hybridization procedures is recommended.
Retinoblastoma ; Biomarkers ; In Situ Hybridization

Objective: To investigate the clinicopathological features, immunophenotypes and molecular genetics of fibroma of tendon sheath (FTS). Methods: One hundred and thirty-four cases of FTS or tenosynovial fibroma diagnosed in the Department of Pathology, West China Hospital, Sichuan University, Chengdu, China from January 2008 to April 2019 were selected. The clinical and histologic features of these cases were retrospectively reviewed. Immunohistochemistry, fluorescence in situ hybridization (FISH) and reverse transcription-polymerase chain reaction (RT-PCR) were performed on the above cases. Results: There were a total of 134 cases of FTS, including 67 males and 67 females. The patients' median age was 38 years (ranged from 2 to 85 years). The median tumor size was 1.8 cm (ranged from 0.1 to 6.8 cm). The most common site was the upper extremity (76/134, 57%). Follow-up data was available in 28 cases and there was no detectable recurrence. Classic FTS (114 cases) were well-defined and hypocellular. A few spindle-shaped fibroblasts were scattered in the dense collagenous sclerotic stroma. Characteristically elongated slit-like spaces or thin-walled vessels were observed. Most of cellular FTSs (20 cases) were well-defined and the area with increased cellularity of the spindle cells coexisted with classic FTS. There were occasional mitotic figures, but no atypical mitotic figures. Immunohistochemistry was performed in 8 cases of classic FTS and most cases were positive for SMA (5/8). Immunohistochemistry was also performed in 13 cases of cellular FTS and showed 100% positive rate for SMA. FISH was conducted on 20 cases of cellular FTS and 32 cases of classical FTS. USP6 gene rearrangement was found in 11/20 of cellular FTS. Among 12 cases of CFTS with nodular fasciitis (NF)-like morphological feature, 7 cases showed USP6 gene rearrangement. The rearrangement proportion of USP6 gene in cellular FTS without NF-like morphological features was 4/8. By contrast, 3% (1/32) of the classic FTS showed USP6 gene rearrangement. RT-PCR was performed in those cases with detected USP6 gene rearrangement and sufficient tissue samples for RT-PCR. The MYH9-USP6 fusion gene was detected in 1 case (1/8) of the cellular FTSs, while no target fusion partner was detected in the classic FTS. Conclusions: FTS is a relatively rare benign fibroblastic or myofibroblastic tumor. Our study and recent literature find that some of the classic FTS also show USP6 gene rearrangements, suggesting that classical FTS and cellular FTS are likely to be at different stages of the same disease (spectrum). FISH for USP6 gene rearrangement may be used as an important auxiliary diagnostic tool in distinguishing FTS from other tumors.
Male ; Female ; Humans ; Gene Rearrangement ; In Situ Hybridization, Fluorescence ; Retrospective Studies ; Fibroma/pathology* ; Fasciitis/genetics* ; Ubiquitin Thiolesterase ; Tendons/pathology*

Objective: To investigate the clinicopathological, immunohistochemical and molecular genetic characteristics of gastric carcinoma with NTRK-rearrangement/amplification. Methods: The clinicopathological data of gastric carcinoma cases with NTRK-rearrangement/amplification diagnosed from January 2011 to September 2020 at the Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, China, were collected. The clinicopathological, immunophenotypic and molecular pathological features were analyzed. The relevant literature was reviewed. Results: There were 4 cases of gastric carcinoma with NTRK-rearrangement/amplification. All 4 patients were male, aged 57-67 years (average, 63 years). Tumor sizes ranged from 3.5 to 5.2 cm (average, 4.8 cm). All tumors were in the antrum. All 4 patients underwent radical gastrectomy and were followed up after the surgery. Morphologically, all tumors showed histological features with enteroblastic-differentiated gastric carcinoma. Tumor cells showed predominantly tubular/papillary architecture, with conspicuous vesicular nuclei and pale staining or transparent cytoplasm. Immunohistochemistry showed pan-TRK expression in all cases, with various degrees of positivity in the cytoplasm. All cases were subject to NTRK1/2/3 detection using fluorescence in situ hybridization. There were NTRK translocations in 2 cases and NTRK amplifications in 2 cases. These cases were further verified by RNAseq next generation sequencing which confirmed that NTRK1 gene translocation (TPM3-NTRK1) and NTRK2 gene translocation (NTRK2-SMCHD1) occurred in two cases, respectively. Conclusions: NTRK mutation occurs less frequently in gastric cancer. In this study, the cases mainly occur in the antrum. The morphology has the characteristics of enteroblastic differentiation. The tumors have unique histological, immunophenotypic and molecular characteristics, which require much attention from pathologists to effectively guide clinicians to choose the best treatment.
Humans ; Male ; Female ; Receptor, trkA/genetics* ; Stomach Neoplasms/surgery* ; In Situ Hybridization, Fluorescence ; Biomarkers, Tumor/genetics* ; Translocation, Genetic ; Carcinoma ; Oncogene Proteins, Fusion/genetics* ; Chromosomal Proteins, Non-Histone/genetics*

Objective: To investigate the clinical, pathological and immunophenotypic features, molecular biology and prognosis of fibrin-associated large B-cell lymphoma (LBCL-FA) in various sites. Methods: Six cases of LBCL-FA diagnosed from April 2016 to November 2021 at the Beijing Friendship Hospital, Capital Medical University, Beijing, China and the First Affiliated Hospital, Wenzhou Medical University, Wenzhou, China were collected. The cases were divided into atrial myxoma and cyst-related groups. Clinical characteristics, pathological morphology, immunophenotype, Epstein Barr virus infection status, B-cell gene rearrangement and fluorescence in situ hybridization of MYC, bcl-2, bcl-6 were summarized. Results: The patients' mean age was 60 years. All of them were male. Three cases occurred in atrial myxoma background, while the others were in cyst-related background, including adrenal gland, abdominal cavity and subdura. All cases showed tumor cells located in pink fibrin clot. However, three cyst-related cases showed the cyst wall with obviously fibrosis and inflammatory cells. All cases tested were non germinal center B cell origin, positive for PD-L1, EBER and EBNA2, and were negative for MYC, bcl-2 and bcl-6 rearrangements, except one case with MYC, bcl-2 and bcl-6 amplification. All of the 5 cases showed monoclonal rearrangement of the Ig gene using PCR based analysis. The patients had detailed follow-ups of 9-120 months, were treated surgically without radiotherapy or chemotherapy, and had long-term disease-free survivals. Conclusions: LBCL-FA is a group of rare diseases occurring in various sites, with predilection in the context of atrial myxoma and cyst-related lesions. Cyst-related lesions with obvious chronic inflammatory background show more scarcity of lymphoid cells and obvious degeneration, which are easy to be missed or misdiagnosed. LBCL-FA overall has a good prognosis with the potential for cure by surgery alone and postoperative chemotherapy may not be necessary.
Humans ; Male ; Middle Aged ; Atrial Fibrillation ; Epstein-Barr Virus Infections ; Fibrin/genetics* ; Herpesvirus 4, Human/genetics* ; In Situ Hybridization, Fluorescence ; Lymphoma, Large B-Cell, Diffuse/pathology* ; Myxoma ; Proto-Oncogene Proteins c-bcl-2/genetics* ; Proto-Oncogene Proteins c-bcl-6/genetics*

Objective: To investigate the clinical phenotype and genetic characteristics of disorders of sex development (DSD) caused by Y chromosome copy number variant (CNV). Methods: A retrospective analysis was performed on 3 patients diagnosed with DSD caused by Y chromosome CNV admitted to the First Affiliated Hospital of Zhengzhou University from January, 2018 to September, 2022. Clinical data were collected. Clinical study and genetic test were performed by karyotyping, whole exome sequencing (WES), low coverage whole genome copy number variant sequencing (CNV-seq), fluorescence in situ hybridization (FISH) and gonadal biopsy. Results: The 3 children, aged 12, 9, 9 years, the social gender were all female, presented with short stature, gonadal dysplasia and normal female external genital. No other phenotypic abnormality was found except for case 1 with scoliosis. The karyotype of all cases were identified as 46, XY. No pathogenic vraiants were found by WES. CNV-seq determined that case 1 was 47, XYY,+Y(2.12) and case 2 was 46, XY,+Y(1.6). FISH concluded that the long arm of Y chromosome was broken and recombined near Yq11.2, and then produced a pseudodicentric chromosome idic(Y). The karyotype was reinterpreted as mos 47, X, idic(Y)(q11.23)×2(10)/46, X, idic(Y)(q11.23)(50) in case 1. The karyotype was redefined as 45, XO(6)/46, X, idic(Y)(q11.22)(23)/46, X, del(Y)(q11.22)(1) in case 2. 46, XY, -Y(mos) was found by CNV-seq in case 3, and the karyotype of 45, XO/46, XY was speculated. Conclusions: The clinical manifestations of children with DSD caused by Y chromosome CNV are short stature and gonadal dysgenesis. If there is an increase of Y chromosome CNV detected by CNV-seq, FISH is recommended to classify the structural variation of Y chromosome.
Humans ; Female ; DNA Copy Number Variations ; In Situ Hybridization, Fluorescence ; Retrospective Studies ; Chromosomes, Human, Y ; Turner Syndrome

Objective To explore the clinicopathological features and prognosis of the patients newly diagnosed with lung adenocarcinoma with both EGFR mutation and C-MET amplification.Methods The pathological sections were reviewed.EGFR mutation was detected by amplification refractory mutation system-quantitative real-time polymerase chain reaction,and C-MET amplification by fluorescence in situ hybridization.The clinicopathological features and survival data of the patients newly diagnosed with lung adenocarcinoma with both EGFR mutation and C-MET amplification were analyzed retrospectively.Results In 11 cases of EGFR mutation combined with C-MET amplification,complex glands and solid high-grade components were observed under a microscope in 10 cases except for one case with a cell block,the tissue structure of which was difficult to be evaluated.The incidence of lung adenocarcinoma in the patients with EGFR mutation combined with C-MET amplification at clinical stage Ⅳ was higher than that in the EGFR mutation or C-MET amplification group (all P<0.001),whereas the difference was not statistically significant between the EGFR mutation group and C-MET amplification group at each clinical stage (all P>0.05).There was no significant difference in the trend of survival rate between EGFR gene group and C-MET amplification group (χ²=0.042,P=0.838),while the survival of the patients with EGFR mutation combined with C-MET amplification was worse than that of the patients with EGFR mutation (χ²=246.72,P<0.001) or C-MET amplification (χ²=236.41,P<0.001).Conclusions The patients newly diagnosed with lung adenocarcinoma with EGFR mutation plus C-MET amplification demonstrate poor histological differentiation,rapid progress,and poor prognosis.The patients are often in the advanced stage when being diagnosed with cancer.Attention should be paid to this concurrent adverse driving molecular event in clinical work.With increasing availability,the inhibitors targeting C-MET may serve as an option to benefit these patients in the near future.
Humans ; In Situ Hybridization, Fluorescence ; Retrospective Studies ; Prognosis ; Adenocarcinoma of Lung/genetics* ; Mutation ; Lung Neoplasms/genetics* ; ErbB Receptors/genetics*

OBJECTIVE: To explore and verify the genes related to female peak bone mass(PBM) and osteoporosis (OP) based on bioinformatics. METHODS: Using GEO data, DNA microarray technology to conduct genome-wide analysis of adult female monocytes with high and low PBM. Cluster analysis, GO enrichment and KEGG analysis were used to analyze the differential genes, and the interaction network of differential genes was further analyzed. OP rat model was established and femur neck tissue staining was performed to further verify the expression of differential genes. RESULTS: A total of 283 genes were obtained by differential gene screening. Compared with the high PBM samples, 135 genes were up-regulated and 148 genes were down-regulated in the low PBM samples. A total of 7 pathways and 12 differential genes were enriched, and there were differences in the expression of several genes involved in mineral absorption and transport, cellular immunity and other aspects. Among them, voltage-gated Ca²⁺ channel 1.3(CaV1.3) encoded by CACNA1D gene was significantly enhanced in the femoral neck tissue of OP rat model. CONCLUSION The above results suggest that the difference in the expression level of CaV1.3 gene may lead to the occurrence of OP in women with low PBM, which provides us with a potential target for the prevention and treatment of OP.
Adult ; Female ; Humans ; Animals ; Rats ; Osteoporosis/genetics* ; Bone Density ; Computational Biology ; Femur Neck ; Staining and Labeling

OBJECTIVE: To validate a fetus with high risk for trisomy 13 suggested by non-invasive prenatal testing (NIPT). METHODS: The fetus was selected as the study subject after the NIPT detection at Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences on February 18, 2019. Clinical data of the pregnant woman was collected. Fluorescence in situ hybridization (FISH), chromosomal karyotyping analysis and chromosomal microarray analysis (CMA) were carried out on amniotic fluid and umbilical cord blood and the couple's peripheral blood samples. Copy number variation sequencing (CNV-seq) was also performed on the placental and amniotic fluid samples following induced labor. RESULTS: The pregnant woman, a 38-year-old G4P1 gravida, was found to have abnormal fetal development by prenatal ultrasonography. NIPT test suggested that the fetus has a high risk for trisomy 13. Chromosomal karyotyping analysis of fetal amniotic fluid and umbilical cord blood were 46,XN,add(13)(p10). The result of CMA was arr[hg19]1q41q44(223937972_249224684)×3, with the size of the repeat fragment being approximately 25.29 Mb, the fetal karyotype was thereby revised as 46,XN,der(13)t(1;13)(q41;p10). Chromosomal karyotyping analysis and CMA of the parents' peripheral blood samples showed no obvious abnormality. The CNV-seq analysis of induced placenta revealed mosaicisms of normal karyotype and trisomy 13. The CNV-seq test of induced amniotic fluid confirmed a duplication of chr1:22446001_249220000 region spanning approximately 24.75 Mb, which was in keeping with the CMA results of amniotic fluid and umbilical cord blood samples. CONCLUSION NIPT may yield false positive result due to placenta mosaicism. Invasive prenatal diagnosis should be recommended to women with a high risk by NIPT test. And analysis of placenta can explain the inconsistency between the results of NIPT and invasive prenatal diagnosis.
Humans ; Female ; Pregnancy ; Trisomy 13 Syndrome/genetics* ; DNA Copy Number Variations ; Placenta ; Chromosomes, Human, Pair 1 ; In Situ Hybridization, Fluorescence ; Prenatal Diagnosis/methods* ; Fetus ; Amniotic Fluid ; Chromosome Aberrations ; Trisomy/genetics*