BACKGROUND: The molecular pathogenesis of gastric carcinoma is not yet well characterized. The purpose of this study is to assess the role of beta-catenin in gastric carcinogenesis. METHODS: We analyzed beta-catenin expression using immunohistochemistry on 68 gastric adenomas and 34 gastric adenocarcinomas, and compared the result with pathological and molecular types of tumors and E-cadherin expression. RESULTS: Nuclear expression of beta-catenin was noted more frequently in gastric adenomas than in carcinomas (40% vs. 21%, 0.05< or = P<1). There was no significant relationship between nuclear beta-catenin expression and histologic degree of adenoma, histologic type of carcinoma or microsatellite instability. E-cadherin expression showed significantly more frequent decrease in the membrane stainability of carcinomas compared to adenomas (P<0.01). CONCLUSIONS: The frequent nuclear beta-catenin expression in gastric adenomas suggests that the beta-catenin alteration might play an early role in gastric carcinogenesis.
Adenocarcinoma ; Adenoma ; beta Catenin* ; Cadherins ; Carcinogenesis* ; Immunohistochemistry ; Membranes ; Microsatellite Instability ; Microsatellite Repeats ; Stomach Neoplasms

Human leukocyte antigen (HLA) is a group of glycoproteins encoded by the major his-tocompatibility complex (MHC) that plays a pivotal role in the host's immune defense.Given that the MHC represents the most polymorphic region in the human genome, HLA typing is crucial in organ transplantation. It significantly influences graft rejection, graft-versus-host disease, and the overall patient outcome by mediating the discrimination between self and nonself. HLA typing technology began with serological methods and has evolved rapidly alongside advances in molecular technologies, progressing from DNA-based typing to next- or third-generation sequencing. These advancements have increased the accuracy of HLA typing and reduced ambiguities, leading to marked improvements in transplantation outcomes. Additionally, numerous novel HLA alleles have been identified. In this review, we explore the developmental history and future prospects of HLA typing technology, which promises to further benefit the field of transplantation.

Human leukocyte antigen (HLA) is a group of glycoproteins encoded by the major his-tocompatibility complex (MHC) that plays a pivotal role in the host's immune defense.Given that the MHC represents the most polymorphic region in the human genome, HLA typing is crucial in organ transplantation. It significantly influences graft rejection, graft-versus-host disease, and the overall patient outcome by mediating the discrimination between self and nonself. HLA typing technology began with serological methods and has evolved rapidly alongside advances in molecular technologies, progressing from DNA-based typing to next- or third-generation sequencing. These advancements have increased the accuracy of HLA typing and reduced ambiguities, leading to marked improvements in transplantation outcomes. Additionally, numerous novel HLA alleles have been identified. In this review, we explore the developmental history and future prospects of HLA typing technology, which promises to further benefit the field of transplantation.

Human leukocyte antigen (HLA) is a group of glycoproteins encoded by the major his-tocompatibility complex (MHC) that plays a pivotal role in the host's immune defense.Given that the MHC represents the most polymorphic region in the human genome, HLA typing is crucial in organ transplantation. It significantly influences graft rejection, graft-versus-host disease, and the overall patient outcome by mediating the discrimination between self and nonself. HLA typing technology began with serological methods and has evolved rapidly alongside advances in molecular technologies, progressing from DNA-based typing to next- or third-generation sequencing. These advancements have increased the accuracy of HLA typing and reduced ambiguities, leading to marked improvements in transplantation outcomes. Additionally, numerous novel HLA alleles have been identified. In this review, we explore the developmental history and future prospects of HLA typing technology, which promises to further benefit the field of transplantation.

Human leukocyte antigen (HLA) is a group of glycoproteins encoded by the major his-tocompatibility complex (MHC) that plays a pivotal role in the host's immune defense.Given that the MHC represents the most polymorphic region in the human genome, HLA typing is crucial in organ transplantation. It significantly influences graft rejection, graft-versus-host disease, and the overall patient outcome by mediating the discrimination between self and nonself. HLA typing technology began with serological methods and has evolved rapidly alongside advances in molecular technologies, progressing from DNA-based typing to next- or third-generation sequencing. These advancements have increased the accuracy of HLA typing and reduced ambiguities, leading to marked improvements in transplantation outcomes. Additionally, numerous novel HLA alleles have been identified. In this review, we explore the developmental history and future prospects of HLA typing technology, which promises to further benefit the field of transplantation.

BACKGROUND: APC and E-cadherin are the key molecules in the Wnt/beta-catenin pathway. We attempted to define the epigenetic alteration of APC and CDH1 (the E-cadherin gene) and the expression of Wnt-related molecules in human mammary carcinomas. METHODS: Sixty-four mammary carcinomas, including 52 invasive ductal carcinomas (IDCs) and 12 invasive lobular carcinomas (ILCs), were evaluated using methylation-specific PCR and immunohistochemistry. We performed immunohistochemistry for E-cadherin, beta-catenin, APC, Wnt1, cyclin D1, ER, PR and C-erb B2. RESULTS: Hypermethylation of APC and CDH1 was observed in 38 (59%) and 28 (44%) cases, respectively. CDH1 hypermethylation in ILCs was increased compared to that in IDCs (p=0.002) and it was associated with the loss of E-cadherin (p=0.02) and beta-catenin (p=0.042). APC methylation was positively correlated with the ER expression (p=0.021). Abnormal cytoplasmic localization of beta-catenin was found in 10 cases and any expression was not detected in six cases. In ILCs, the E-cadherin or beta-catenin expression was markedly decreased compared to that in IDCs (p<0.001 in both). CONCLUSIONS: Methylation of APC or CDH1 was relatively frequent in mammary carcinomas. The loss of E-cadherin in mammary carcinoma was associated with CDH1 methylation, and abnormal beta-catenin expression was related to the loss of E-cadherin in ILC.
beta Catenin ; Breast ; Breast Neoplasms ; Cadherins ; Carcinoma, Ductal ; Carcinoma, Lobular ; Cyclin D1 ; Cytoplasm ; DNA Methylation ; Epigenomics ; Immunohistochemistry ; Methylation ; Polymerase Chain Reaction ; Wnt1 Protein

Purpose: In this study, we investigated the frequencies of mutations in DNA damage repair genesincluding BRCA1, BRCA2, homologous recombination genes and TP53 gene in ovarian highgradeserous carcinoma, alongside those of germline and somatic BRCA mutations, withthe aim of improving the identification of patients suitable for treatment with poly(ADPribose)polymerase inhibitors. Materials and Methods: Tissue samples from 77 Korean patients with ovarian high-grade serous carcinoma weresubjected to next-generation sequencing. Pathogenic alterations of 38 DNA damage repairgenes and TP53 gene and their relationships with patient survival were examined. Additionally,we analyzed BRCA germline variants in blood samples from 47 of the patients forcomparison. Results: BRCA1, BRCA2, and TP53 mutations were detected in 28.6%, 5.2%, and 80.5% of the 77patients, respectively. Alterations in RAD50, ATR, MSH6, MSH2, and FANCA were also identified.At least one mutation in a DNA damage repair gene was detected in 40.3% of patients(31/77). Germline and somatic BRCA mutations were found in 20 of 47 patients (42.6%),and four patients had only somatic mutations without germline mutations (8.5%, 4/47).Patients with DNA damage repair gene alterations with or without TP53mutation, exhibitedbetter disease-free survival than those with TP53 mutation alone. Conclusion DNA damage repair genes were mutated in 40.3% of patients with high-grade serous carcinoma,with somatic BRCAmutations in the absence of germline mutation in 8.5%. Somaticvariant examination, along with germline testing of DNA damage repair genes, has potentialto detect additional candidates for PARP inhibitor treatment.

Background: The importance of molecular pathology tests has increased during the last decade, and there is a great need for efficient training of molecular pathology for pathology trainees and as continued medical education. Methods: The Molecular Pathology Study Group of the Korean Society of Pathologists appointed a task force composed of experienced molecular pathologists to develop a refined educational curriculum of molecular pathology. A 3-day online educational session was held based on the newly established structure of learning objectives; the audience were asked to score their understanding of 22 selected learning objectives before and after the session to assess the effect of structured education. Results: The structured objectives and goals of molecular pathology was established and posted as a web-based interface which can serve as a knowledge bank of molecular pathology. A total of 201 pathologists participated in the educational session. For all 22 learning objectives, the scores of self-reported understanding increased after educational session by 9.9 points on average (range, 6.6 to 17.0). The most effectively improved items were objectives from next-generation sequencing (NGS) section: ‘NGS library preparation and quality control’ (score increased from 51.8 to 68.8), ‘NGS interpretation of variants and reference database’ (score increased from 54.1 to 68.0), and ‘whole genome, whole exome, and targeted gene sequencing’ (score increased from 58.2 to 71.2). Qualitative responses regarding the adequacy of refined educational curriculum were collected, where favorable comments dominated. Conclusions Approach toward the education of molecular pathology was refined, which would greatly benefit the future trainees.