Clinicopathological and molecular features of genome-stable colorectal cancers.

Colorectal cancers (CRCs) are traditionally divided into those with either chromosomal instability (CIN) or microsatellite instability (MSI). By utilizing TCGA data, the Laird team found a subset of CRCs, namely, genome-stable CRCs (GS CRCs), which lack both CIN and MSI. Although the molecular features of GS CRCs have been described in detail, the clinicopathological features are not well defined. A total of 437 CRCs were analyzed for copy number variation (CNV) statuses in eight genes (ARID1A, EGFR, FGFR1, KDM5B, MYBL2, MYC, SALL4, and SETDB1) using droplet-digital PCR. CRCs that showed CNV in ≤ one gene and no MSI were defined as GS-like CRCs. Clinicopathological and molecular features of GS-like CRCs were compared with those of CIN-like CRCs. GS-like CRCs comprised 4.6% of CRCs and showed a predilection toward the proximal colon, lower nuclear optical density, KRAS mutation, PIK3CA mutation, and aberrant expression of KRT7. Survival analysis showed no significant difference between the three subgroups. Through our study, the GS-like subtype was found to comprise a minor proportion of CRCs and have proclivity toward a proximal bowel location, hypochromatic tumor nuclei, aberrant KRT7 expression, and a high frequency of KRAS and PIK3CA mutations.

Transformation of t(14;18)-negative follicular lymphoma to plasmablastic lymphoma: a case report with analysis of genetic evolution.

BACKGROUND: Follicular lymphoma (FL) is characterized by t(14;18)(q32;q21) involving the IGH and BCL2 genes. However, 10-15% of FLs lack the BCL2 rearrangement. These BCL2-rearrangement-negative FLs are clinically, pathologically, and genetically heterogeneous. The biological behavior and histological transformation of such FLs are not adequately characterized. Here, we report the first case of t(14;18)-negative FL that rapidly progressed to plasmablastic lymphoma (PBL). CASE PRESENTATION: A previously healthy 51-year-old man presented with leg swelling. Computed tomography (CT) showed enlarged lymph nodes (LNs) throughout the body, including both inguinal areas. Needle biopsy of an inguinal LN suggested low-grade B-cell non-Hodgkin lymphoma. Excisional biopsy of a neck LN showed proliferation of centrocytic and centroblastic cells with follicular and diffuse growth patterns. Immunohistochemical analysis showed that the cells were positive for CD20, BCL6, CD10, and CD23. BCL2 staining was negative in the follicles and weak to moderately positive in the interfollicular areas. BCL2 fluorescence in situ hybridization result was negative. Targeted next-generation sequencing (NGS) revealed mutations in the TNFRSF14, CREBBP, STAT6, BCL6, CD79B, CD79A, and KLHL6 genes, without evidence of BCL2 or BCL6 rearrangement. The pathologic and genetic features were consistent with t(14;18)-negative FL. Two months after one cycle of bendamustine and rituximab chemotherapy, the patient developed left flank pain. Positron emission tomography/CT showed new development of a large hypermetabolic mass in the retroperitoneum. Needle biopsy of the retroperitoneal mass demonstrated diffuse proliferation of large plasmablastic cells, which were negative for the B-cell markers, BCL2, BCL6, and CD10; they were positive for MUM-1, CD138, CD38, and C-MYC. The pathologic findings were consistent with PBL. The clonal relationship between the initial FL and subsequent PBL was analyzed via targeted NGS. The tumors shared the same CREBBP, STAT6, BCL6, and CD79B mutations, strongly suggesting that the PBL had transformed from a FL clone. The PBL also harbored BRAF V600E mutation and IGH::MYC fusion in addition to IGH::IRF4 fusion. CONCLUSIONS: We propose that transformation or divergent clonal evolution of FL into PBL can occur when relevant genetic mutations are present. This study broadens the spectrum of histological transformation of t(14;18)-negative FL and emphasizes its biological and clinical heterogeneity.

Colon cancer: the 2023 Korean clinical practice guidelines for diagnosis and treatment.

Colorectal cancer is the third most common cancer in Korea and the third leading cause of death from cancer. Treatment outcomes for colon cancer are steadily improving due to national health screening programs with advances in diagnostic methods, surgical techniques, and therapeutic agents.. The Korea Colon Cancer Multidisciplinary (KCCM) Committee intends to provide professionals who treat colon cancer with the most up-to-date, evidence-based practice guidelines to improve outcomes and help them make decisions that reflect their patients' values and preferences. These guidelines have been established by consensus reached by the KCCM Guideline Committee based on a systematic literature review and evidence synthesis and by considering the national health insurance system in real clinical practice settings. Each recommendation is presented with a recommendation strength and level of evidence based on the consensus of the committee.

Concomitant expression patterns of CDX2 and SATB2 as prognostic factors in stage III colorectal cancers.

CDX2 and SATB2 are often used as biomarkers for identification of colorectal origin in primary or metastatic adenocarcinomas. Loss of CDX2 or SATB2 expression has been associated with poor prognosis in patients with colorectal cancer (CRC). However, little is known regarding clinicopathological features, including prognosis, of CRCs with concomitant loss of CDX2 and SATB2. A total of 431 stage III CRCs were analyzed for their expression status in CDX2 and SATB2 using tissue microarray-based immunohistochemistry and expression status was correlated with clinicopathological variables, molecular alterations, and survival. CDX2-negative (CDX2-) CRCs and SATB2-negative (SATB2-) CRCs were found in 8.1 % and 17.2 % of CRCs, respectively, whereas both CDX2-negative and SATB2-negative (CDX2-/SATB2-) CRCs comprised 3.2 % of the CRCs. On survival analysis, neither CDX2-/SATB2+ nor CDX2+/SABT2- CRCs but CDX2-/SATB2- CRCs were associated with poor prognosis. CDX2-/SATB2- CRCs showed significant associations with tumor subsite of right colon, poor differentiation, decreased expression of CK20, aberrant expression of CK7, CIMP-high, MSI-high, and BRAF mutation. In summary, our results suggest that concomitant loss of CDX2 and SATB2 is a prognostic biomarker but isolated loss of CDX2 or SATB2 is not a prognostic biomarker for stage III CRCs.

Protein Signatures of Parathyroid Adenoma according to Tumor Volume and Functionality.

BACKGRUOUND: Parathyroid adenoma (PA) is a common endocrine disease linked to multiple complications, but the pathophysiology of the disease remains incompletely understood. The study aimed to identify the key regulator proteins and pathways of PA according to functionality and volume through quantitative proteomic analyses. METHODS: We conducted a retrospective study of 15 formalin-fixed, paraffin-embedded PA samples from tertiary hospitals in South Korea. Proteins were extracted, digested, and the resulting peptides were analyzed using liquid chromatography-tandem mass spectrometry. Pearson correlation analysis was employed to identify proteins significantly correlated with clinical variables. Canonical pathways and transcription factors were analyzed using Ingenuity Pathway Analysis. RESULTS: The median age of the participants was 52 years, and 60.0% were female. Among the 8,153 protein groups analyzed, 496 showed significant positive correlations with adenoma volume, while 431 proteins were significantly correlated with parathyroid hormone (PTH) levels. The proteins SLC12A9, LGALS3, and CARM1 were positively correlated with adenoma volume, while HSP90AB2P, HLA-DRA, and SCD5 showed negative correlations. DCPS, IRF2BPL, and FAM98A were the main proteins that exhibited positive correlations with PTH levels, and SLITRK4, LAP3, and AP4E1 had negative correlations. Canonical pathway analysis demonstrated that the RAN and sirtuin signaling pathways were positively correlated with both PTH levels and adenoma volume, while epithelial adherence junction pathways had negative correlations. CONCLUSION: Our study identified pivotal proteins and pathways associated with PA, offering potential therapeutic targets. These findings accentuate the importance of proteomics in understanding disease pathophysiology and the need for further research.

Establishing molecular pathology curriculum for pathology trainees and continued medical education: a collaborative work from the Molecular Pathology Study Group of the Korean Society of Pathologists.

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.

Spatial and clonality-resolved 3D cancer genome alterations reveal enhancer-hijacking as a potential prognostic marker for colorectal cancer.

The regulatory effect of non-coding large-scale structural variations (SVs) on proto-oncogene activation remains unclear. This study investigated SV-mediated gene dysregulation by profiling 3D cancer genome maps from 40 patients with colorectal cancer (CRC). We developed a machine learning-based method for spatial characterization of the altered 3D cancer genome. This revealed a frequent establishment of "de novo chromatin contacts" that can span multiple topologically associating domains (TADs) in addition to the canonical TAD fusion/shuffle model. Using this information, we precisely identified super-enhancer (SE)-hijacking and its clonal characteristics. Clonal SE-hijacking genes, such as TOP2B, are recurrently associated with cell-cycle/DNA-processing functions, which can potentially be used as CRC prognostic markers. Oncogene activation and increased drug resistance due to SE-hijacking were validated by reconstructing the patient's SV using CRISPR-Cas9. Collectively, the spatial and clonality-resolved analysis of the 3D cancer genome reveals regulatory principles of large-scale SVs in oncogene activation and their clinical implications.

In-depth proteomic signature of parathyroid carcinoma.

OBJECTIVE: Diagnosing parathyroid carcinoma (PC) is complicated and controversial that early diagnosis and intervention are often difficult. Therefore, we aimed to elucidate the protein signatures of PC through quantitative proteomic analyses to aid in the early and accurate diagnosis of PC. DESIGN: We conducted a retrospective cohort study. METHODS: We performed liquid chromatography with tandem mass spectrometry using formalin-fixed paraffin-embedded samples. For the analyses, 23 PC and 15 parathyroid adenoma (PA) tissues were collected from 6 tertiary hospitals in South Korea. RESULTS: The mean age of the patients was 52 years, and 63% were women. Proteomic expression profiling revealed 304 differentially expressed proteins (DEPs) with a cut-off of P < .05 and fold change >1.5. Among DEPs, we identified a set of 5 proteins that can discriminate PC from PA: carbonic anhydrase 4 (CA4), alpha/beta hydrolase domain-containing protein 14B (ABHD14B), laminin subunit beta-2 (LAMB2), CD44 antigen (CD44), and alpha-1-acid glycoprotein 1 (ORM1) that exhibited the highest area under the curve of 0.991 in neural network model. The nuclear percentage of CA4 and LAMB2 in immunohistochemistry was significantly lower in PC tissue than in the PA (CA4: 2.77 ± 1.96%, 26.2 ± 3.45%, P < .001; LAMB2: 6.86 ± 3.46%, 38.54 ± 4.13%, P < .001). The most enriched canonical pathways in PC included glycoprotein-6 signaling and mammalian target of rapamycin (mTOR). CONCLUSIONS: We identified key proteins differentially expressed between PC and PA using proteomic analyses of parathyroid neoplasms. These findings may help to diagnose PC accurately and elucidate potential therapeutic targets.

Mutations of TP53 and genes related to homologous recombination repair in breast cancer with germline BRCA1/2 mutations.

BACKGROUND: Germline mutations of breast cancer susceptibility gene BRCA1 and BRCA2 (gBRCA1/2) are associated with elevated risk of breast cancer in young women in Asia. BRCA1 and BRCA2 proteins contribute to genomic stability through homologous recombination (HR)-mediated double-strand DNA break repair in cooperation with other HR-related proteins. In this study, we analyzed the targeted sequencing data of Korean breast cancer patients with gBRCA1/2 mutations to investigate the alterations in HR-related genes and their clinical implications. MATERIALS AND METHODS: Data of the breast cancer patients with pathogenic gBRCA1/2 mutations and qualified targeted next-generation sequencing, SNUH FiRST cancer panel, were analyzed. Single nucleotide polymorphisms, small insertions, and deletions were analyzed with functional annotations using ANNOVAR. HR-related genes were defined as ABL1, ATM, ATR, BARD1, BRCA1, BRCA2, CDKN1A, CDKN2A, CHEK1, CHEK2, FANCA, FANCD2, FANCG, FANCI, FANCL, KDR, MUTYH, PALB2, POLE, POLQ, RAD50, RAD51, RAD51D, RAD54L, and TP53. Mismatch-repair genes were MLH1, MSH2, and MSH6. Clinical data were analyzed with cox proportional hazard models and survival analyses. RESULTS: Fifty-five Korean breast cancer patients with known gBRCA1/2 mutations and qualified targeted NGS data were analyzed. Ethnically distinct mutations in gBRCA1/2 genes were noted, with higher frequencies of Val1833Ser (14.8%), Glu1210Arg (11.1%), and Tyr130Ter (11.1%) in gBRCA1 and Arg2494Ter (25.0%) and Lys467Ter (14.3%) in gBRCA2. Considering subtypes, gBRCA1 mutations were associated with triple-negative breast cancers (TNBC), while gBRCA2 mutations were more likely hormone receptor-positive breast cancers. At least one missense mutation of HR-related genes was observed in 44 cases (80.0%). The most frequently co-mutated gene was TP53 (38.1%). In patients with gBRCA1/2 mutations, however, genetic variations of TP53 occurred in locations different from the known hotspots of those with sporadic breast cancers. The patients with both gBRCA1/2 and TP53 mutations were more likely to have TNBC, high Ki-67 values, and increased genetic mutations, especially of HR-related genes. Survival benefit was observed in the TP53 mutants of patients with gBRCA2 mutations, compared to those with TP53 wild types. CONCLUSION: Our study showed genetic heterogeneity of breast cancer patients with gBRCA1 and gBRCA2 mutations in the Korean populations. Further studies on precision medicine are needed for tailored treatments of patients with genetic diversity among different ethnic groups.

Prognostic Impact of Extramural Lymphatic, Vascular, and Perineural Invasion in Stage II Colon Cancer: A Comparison With Intramural Invasion.

BACKGROUND: Lymphatic invasion, vascular invasion, and perineural invasion are prognostic factors for colon cancer. However, the prognostic significance of those factors according to the location of permeation (intramural and extramural invasion) in stage II colon cancer is still unclear. OBJECTIVE: This study aimed to clarify whether the location of lymphatic invasion, vascular invasion, and perineural invasion could affect the survival of patients with stage II colon cancer. DESIGN: This was a retrospective cohort study. SETTINGS: This study took place at a university teaching hospital. PATIENTS: A total of 1130 patients with stage II colon cancers who underwent radical surgery at the Seoul National University Hospital between July 2003 and December 2015 were included. MAIN OUTCOME MEASURES: Patients were classified according to the location of lymphatic invasion, vascular invasion, and perineural invasion. Survival outcomes were compared among those without invasion and those with intramural and extramural invasion. Primary end point is overall survival and secondary end point is disease-free survival. RESULTS: Disease-free survival and overall survival of patients with extramural invasion were worse than those of patients without invasion and those with intramural invasion. Multivariate analysis for survival outcomes confirmed that extramural invasion was a significant independent prognostic factor. However, both disease-free survival and overall survival were not significantly different between patients without invasion and those with intramural invasion. LIMITATIONS: This study was limited by its retrospective design. CONCLUSIONS: Extramural invasion was associated with worse prognosis in stage II colon cancer, but intramural invasion was not. Therefore, pathologic reports about the location of lymphatic invasion, vascular invasion, and perineural invasion might be helpful for predicting prognosis and for determining the need of adjuvant chemotherapy in stage II colon cancers. See Video Abstract at http://links.lww.com/DCR/B939 . IMPACTO PRONSTICO DE LA INVASION EXTRAMURAL LINFTICA, VASCULAR Y PERINEURAL EN EL CNCER DE COLON ESTADO II ESTUDIO COMPARATIVO CON RELACIN A LA INVASIN INTRAMURAL: ANTECEDENTES:La invasión linfática, vascular y perineural son factores pronósticos para el cáncer de colon. Sin embargo, la importancia pronóstica de estos factores de acuerdo con la ubicación de la permeabilidad (invasión intramural y extramural) del cáncer de colon en estadío II aún no está aclarada.OBJETIVO:El presente estudio tiene por objetivo, el de aclarar si la localización de la invasión linfática, vascular y perineural podría afectar la sobrevida en los pacientes con cáncer de colon en estadío II.DISEÑO:Estudio de cohortes de caracter retrospectivo.AJUSTES:Nuestro estudio se llevó a cabo en un hospital docente universitario.PACIENTES:Se incluyeron un total de 1130 pacientes diagnosticados con cáncer de colon en estadío II, los cuales fueron sometidos a cirugía radical en el Hospital Universitario Nacional de Seúl, entre julio de 2003 y diciembre de 2015.PRINCIPALES MEDIDAS DE RESULTADO:Los pacientes fueron clasificados según la localización de la invasión linfática, vascular y perineural. Los resultados de la sobrevida fueron comparados con aquellos sin invasión y los otros con invasión intramural y extramural. El objetivo final primario fué la sobrevida global, el objetivo final secundario fué la sobrevida libre de enfermedad.RESULTADOS:La sobrevida libre de enfermedad y la sobrevida global de los pacientes con invasión extramural fueron mucho peores en relacion a las de los pacientes sin invasión y aquellos con invasión intramural. El análisis multivariado de los resultados de la sobrevida confirmaron que la invasión extramural es un factor pronóstico independiente muy significativo. Sin embargo, tanto la sobrevida libre de enfermedad, como la sobrevida global no fueron significativamente diferentes entre los pacientes sin invasión y aquellos con invasión intramural.LIMITACIONES:Estudio limitado por su diseño con caracter retrospectivo.CONCLUSIONES:La invasión extramural fué asociada con un peor pronóstico en el cáncer de colon en estadío II, pero la invasión intramural no lo fué. Por tanto, los informes anatomopatológicos sobre la ubicación de la invasión linfática, vascular y perineural, podrían ser útiles para predecir el pronóstico y determinar el menester de la quimioterapia adyuvante en los cánceres de colon en estadío II. Consulte Video Resumen en http://links.lww.com/DCR/B939 . (Traducción-Dr. Xavier Delgadillo ).

Development of quality assurance program for digital pathology by the Korean Society of Pathologists.

BACKGROUND: Digital pathology (DP) using whole slide imaging is a recently emerging game changer technology that can fundamentally change the way of working in pathology. The Digital Pathology Study Group (DPSG) of the Korean Society of Pathologists (KSP) published a consensus report on the recommendations for pathologic practice using DP. Accordingly, the need for the development and implementation of a quality assurance program (QAP) for DP has been raised. METHODS: To provide a standard baseline reference for internal and external QAP for DP, the members of the Committee of Quality Assurance of the KSP developed a checklist for the Redbook and a QAP trial for DP based on the prior DPSG consensus report. Four leading institutes participated in the QAP trial in the first year, and we gathered feedback from these institutes afterwards. RESULTS: The newly developed checklists of QAP for DP contain 39 items (216 score): eight items for quality control of DP systems; three for DP personnel; nine for hardware and software requirements for DP systems; 15 for validation, operation, and management of DP systems; and four for data security and personal information protection. Most participants in the QAP trial replied that continuous education on unfamiliar terminology and more practical experience is demanding. CONCLUSIONS: The QAP for DP is essential for the safe implementation of DP in pathologic practice. Each laboratory should prepare an institutional QAP according to this checklist, and consecutive revision of the checklist with feedback from the QAP trial for DP needs to follow.

Composite scoring system and optimal tumor budding cut-off number for estimating lymph node metastasis in submucosal colorectal cancer.

BACKGROUND: Tumor budding is associated with lymph node (LN) metastasis in submucosal colorectal cancer (CRC). However, the rate of LN metastasis associated with the number of tumor buds is unknown. Here, we determined the optimal tumor budding cut-off number and developed a composite scoring system (CSS) for estimating LN metastasis of submucosal CRC. METHODS: In total, 395 patients with histologically confirmed T1N0-2M0 CRC were evaluated. The clinicopathological characteristics were subjected to univariate and multivariate analyses. The Akaike information criterion (AIC) values of the multivariate models were evaluated to identify the optimal cut-off number. A CSS for LN metastasis was developed using independent risk factors. RESULTS: The prevalence of LN metastasis was 13.2%. Histological differentiation, lymphatic or venous invasion, and tumor budding were associated with LN metastasis in univariate analyses. In multivariate models adjusted for histological differentiation and lymphatic or venous invasion, the AIC value was lowest for five tumor buds. Unfavorable differentiation (odds ratio [OR], 8.16; 95% confidence interval [CI], 1.80-36.89), lymphatic or venous invasion (OR, 5.91; 95% CI, 2.91-11.97), and five or more tumor buds (OR, 3.01; 95% CI, 1.21-7.69) were independent risk factors. In a CSS using these three risk factors, the rates of LN metastasis were 5.6%, 15.5%, 31.0%, and 52.4% for total composite scores of 0, 1, 2, and ≥ 3, respectively. CONCLUSIONS: For the estimation of LN metastasis in submucosal CRC, the optimal tumor budding cut-off number was five. Our CSS can be utilized to estimate LN metastasis.

Intratumoral spatial heterogeneity of tumor-infiltrating lymphocytes is a significant factor for precisely stratifying prognostic immune subgroups of microsatellite instability-high colorectal carcinomas.

Although the density of tumor-infiltrating lymphocytes (TILs) is known to be linked to prognosis in various cancers, the prognostic impact and immunologic significance of the spatial heterogeneity of TILs have been rarely investigated. In this study, CD3+ and CD8+ TILs were quantified in independent cohorts (discovery, n = 73; and external validation, n = 93) of colorectal carcinomas (CRCs) with microsatellite instability-high (MSI-H) utilizing whole-slide image analysis of CD3/CD8 immunohistochemistry. The Shannon and Simpson indices, which measure intratumoral patch-to-patch evenness of TIL densities, were used to quantitatively assess the spatial heterogeneity of TILs in each case. To uncover immune-related gene expression signatures of spatial heterogeneity-based TIL subgroups of MSI-H CRCs, representative cases were subjected to GeoMx digital spatial profiler (DSP) analysis. As expected, a low density of TILs was significantly associated with poor disease-free survival (DFS) in MSI-H CRCs. The TIL-low tumors were further classified into two subgroups based on the spatial heterogeneity of TILs: TIL-low/heterogeneity-high and TIL-low/heterogeneity-low subgroups. In both discovery and validation cohorts, the TIL-low/heterogeneity-high, TIL-low/heterogeneity-low, and TIL-high subgroups were significantly associated with poor, intermediate, and good DFS, respectively. In the DSP analysis, the TIL-low/heterogeneity-high subgroup showed higher spatial diversity in the expression of immune-related genes than that of the TIL-low/heterogeneity-low subgroup and exhibited upregulation of genes related to immune checkpoints, chemokine/cytokine receptors, and myeloid cells. TIL-low/heterogeneity-high tumors were also enriched with gene sets related to good response to immune checkpoint inhibitor therapy. In conclusion, TIL-low MSI-H CRCs are prognostically heterogeneous and can be divided into prognostically and immunologically distinct subgroups by considering the spatial heterogeneity of TILs. Our data suggest that intratumoral spatial heterogeneity of TILs can be used as a key element for clinically relevant immunologic subtyping of tumors.

Multifocal organoids reveal clonal associations between synchronous intestinal tumors with pervasive heterogeneous drug responses.

Multifocal colorectal cancer (CRC) comprises both clonally independent primary tumors caused by inherited predisposition and clonally related tumors mainly due to intraluminal spreading along an intact basement membrane. The distinction between these multifocal CRCs is essential because therapeutic strategies vary according to the clonal association of multiple tumor masses. Here, we report one unique case of synchronous intestinal cancer (SIC) with tumors occurring along the entire bowel tract, including the small intestine. We established six patient-derived organoids (PDOs), and patient-derived cell lines (PDCs) from each site of the SIC, which were subjected to extensive genomic, transcriptomic, and epigenomic sequencing. We also estimated the drug responses of each multifocal SIC to 25 clinically relevant therapeutic compounds to validate how the clinically actionable alternations between SICs were associated with drug sensitivity. Our data demonstrated distinct clonal associations across different organs, which were consistently supported by multi-omics analysis, as well as the accordant responses to various therapeutic compounds. Our results indicated the imminent drawback of a single tumor-based diagnosis of multifocal CRC and suggested the necessity of an in-depth molecular analysis of all tumor regions to avoid unexpected resistance to the currently available targeted therapies.

Pediatric-Type Indolent B-Cell Lymphomas With Overlapping Clinical, Pathologic, and Genetic Features.

Pediatric-type follicular lymphoma (PTFL) and pediatric nodal marginal zone lymphoma (PNMZL) are rare pediatric-type indolent B-cell lymphomas (PedIBCL) that differ clinicopathologically from their adult counterparts. Accurate diagnosis is important to avoid overtreatment but is often challenging. The mutational landscape of PTFL is known and may aid diagnosis, but the genetic features of PNMZL are not well understood. We analyzed 21 cases of PedIBCL according to their clinicopathologic findings and classified them into PTFL (n=11), PNMZL (n=2), and "mixed type" tumors (n=8) showing ambiguous histology. We also analyzed 2 cases of adult B-cell lymphomas showing features of PedIBCL. Targeted sequencing of 121 lymphoma-related genes was performed. The median age of PedIBCL patients was 16 years (range: 3 to 47), and all but 1 PTFL patient were male. All patients presented with limited-stage disease, and only 1 relapsed. There were no significant differences in clinical features among the 3 PedIBCL groups. The most frequently mutated genes were MAP2K1 , TNFRSF14 , KMT2C , IRF8 , and NOTCH2 . The genetic features of all groups were similar to the established mutational landscape of PTFL. The 2 adult B-cell lymphomas cases also had MAP2K1 , TNFRSF14 , and IRF8 mutations, but the clinical features were not typical of PedIBCL. In summary, this study demonstrated that PTFL and PNMZL are similar diseases with overlapping clinical, pathologic, and genetic features; mixed type tumors can also occur. Atypical adult cases with similar histologic features were also observed. Therefore, the disease spectrum of PedIBCL may be much broader than is currently believed.

Identification of tissue of origin in cancer of unknown primary using a targeted bisulfite sequencing panel.

Aim: To construct a targeted bisulfite sequencing panel predicting origin of cancer of unknown primary. Methods: A bisulfite sequencing panel targeting 2793 tissue-specific markers was performed in 100 clinical samples. Results: The authors' prediction model showed 0.85 accuracy for the 'first-ranked' tissue type and 0.93 accuracy for the 'second-ranked' tissue type using 2793 tissue-specific markers and 0.84 accuracy for the 'first-ranked' tissue type and 0.92 accuracy for the 'second-ranked' tissue type when the number of tissue-specific markers was reduced to 514. Conclusion: Targeted bisulfite sequencing is a useful method for predicting the tissue of origin in patients with cancer of unknown primary.

When patients with cancer present with tumors that have migrated from elsewhere in the body, it is difficult for clinicians to identify where the cancer originated. DNA methylation profiling is a promising test to help identify where the cancer originated because it reflects cell of origin and is compatible with formalin-fixed, paraffin-embedded tissues. Because next-generation sequencing has already been implemented in clinical laboratories, the authors developed a targeted bisulfite sequencing panel that could predict the tissue of origin using genomic DNA extracted from formalin-fixed, paraffin-embedded tissues. The authors found that a hybrid capture-based targeted bisulfite sequencing panel is a useful method for predicting the tissue of origin in patients with cancer of unknown primary origin in clinical practice.

Tauroursodeoxycholic Acid Inhibits Nuclear Factor Kappa B Signaling in Gastric Epithelial Cells and Ameliorates Gastric Mucosal Damage in Mice.

Background/Aims: Previous studies have reported the protective effects of tauroursodeoxycholic acid (TUDCA) on gastric epithelial cells in some animal models, but the precise mechanisms are unclear. This study examined the effects of TUDCA on NF-κB signaling in gastric epithelial cells. Moreover, the protective effects of TUDCA in experimental gastritis models induced by ethanol and NSAID were evaluated and compared with ursodeoxycholic acid (UDCA). Methods: After a pretreatment with TUDCA or UDCA, human gastric epithelial MKN-45 cells were stimulated with tumor necrosis factor (TNF)-α to activate NF-κB signaling. A real-time PCR (RT-PCR) for human interleukin (IL)-1 mRNA was performed. An electrophoretic mobility shift assay (EMSA) and immunoblot analyses were carried out. In murine models, after a pretreatment with TUDCA or UDCA, ethanol and indomethacin were administered via oral gavage. Macroscopic and microscopic assessments were performed to evaluate the preventive effects of TUDCA and UDCA on murine gastritis. Results: A pretreatment with TUDCA downregulated the IL-1α mRNA levels in MKN-45 cells stimulated with TNF-α, as assessed by RT-PCR. As determined using EMSA, a pretreatment with TUDCA reduced the TNF-α-induced NF-κB DNA binding activity. A pretreatment with TUDCA inhibited IκBα phosphorylation induced by TNF-α, as assessed by immunoblot analysis. TUDCA attenuated the ethanol-induced and NSAID-induced gastritis in murine models, as determined macroscopically and microscopically. Conclusions: TUDCA inhibited NF-κB signaling in gastric epithelial cells and ameliorated ethanol- and NSAID-induced gastritis in murine models. These results support the potential of TUDCA for the prevention of gastritis in humans.

Combinatory statuses of tumor stromal percentage and tumor infiltrating lymphocytes as prognostic factors in stage III colorectal cancers.

BACKGROUND AND AIM: Tumor stroma and tumor-infiltrating lymphocytes (TILs) are major constituents of the tumor microenvironment, although they have different effects on the prognosis of patients with colorectal cancer (CRC). Combinatory statuses of tumor-stromal percentage (TSP) and TILs are expected to provide more powerful prognostic information but have never been studied in CRCs. METHODS: Stage III CRCs from patients (n = 487) treated with adjuvant chemotherapy were assessed for their TSP and CD3-TIL or CD8-TIL densities using computer-aided methodology. With cut-off values set at median values for intraepithelial TIL (iTIL) and stromal TIL (sTIL) densities, CRCs were sorted into low and high iTIL or sTIL groups. CRCs were classified into five quintile (Q1-Q5) groups according to their TSP and divided into high TSP (Q5) and low TSP (Q1-4) groups. RESULTS: The combination of CD8 iTIL density and TSP was found to be an independent prognostic parameter in multivariate survival analysis in terms of cancer-specific survival and recurrence-free survival. CRCs with low CD8 iTIL density and high TSP showed the worst survival. The combinatory status showed more prognostic power than CD8 iTIL density or TSP alone. Multivariate survival analysis in an independent cohort of stage III CRC validated the prognostic power of the combinatory statuses. CONCLUSIONS: The findings suggest that the combinatory status might serve as a prognostic parameter in stage III CRCs. Further research in a large-scale cohort of patients with stage III CRC is needed to validate the prognostic power of the combinatory status.