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result(s) for
"Chee Leong Cheng"
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Genetic risk of extranodal natural killer T-cell lymphoma: a genome-wide association study in multiple populations
2020
Extranodal natural killer T-cell lymphoma (NKTCL; nasal type) is an aggressive malignancy with a particularly high prevalence in Asian and Latin American populations. Epstein-Barr virus infection has a role in the pathogenesis of NKTCL, and HLA-DPB1 variants are risk factors for the disease. We aimed to identify additional novel genetic variants affecting risk of NKTCL.
We did a genome-wide association study of NKTCL in multiple populations from east Asia. We recruited a discovery cohort of 700 cases with NKTCL and 7752 controls without NKTCL of Han Chinese ancestry from 19 centres in southern, central, and northern regions of China, and four independent replication samples including 717 cases and 12 650 controls. Three of these independent samples (451 cases and 5301 controls) were from eight centres in the same regions of southern, central, and northern China, and the fourth (266 cases and 7349 controls) was from 11 centres in Hong Kong, Taiwan, Singapore, and South Korea. All cases had primary NKTCL that was confirmed histopathologically, and matching with controls was based on geographical region and self-reported ancestry. Logistic regression analysis was done independently by geographical regions, followed by fixed-effect meta-analyses, to identify susceptibility loci. Bioinformatic approaches, including expression quantitative trait loci, binding motif and transcriptome analyses, and biological experiments were done to fine-map and explore the functional relevance of genome-wide association loci to the development of NKTCL.
Genetic data were gathered between Jan 1, 2008, and Jan 23, 2019. Meta-analysis of all samples (a total of 1417 cases and 20 402 controls) identified two novel loci significantly associated with NKTCL: IL18RAP on 2q12.1 (rs13015714; p=2·83 × 10−16; odds ratio 1·39 [95% CI 1·28–1·50]) and HLA-DRB1 on 6p21.3 (rs9271588; 9·35 × 10−26 1·53 [1·41–1·65]). Fine-mapping and experimental analyses showed that rs1420106 at the promoter of IL18RAP was highly correlated with rs13015714, and the rs1420106-A risk variant had an upregulatory effect on IL18RAP expression. Cell growth assays in two NKTCL cell lines (YT and SNK-6 cells) showed that knockdown of IL18RAP inhibited cell proliferation by cell cycle arrest in NKTCL cells. Haplotype association analysis showed that haplotype 47F-67I was associated with reduced risk of NKTCL, whereas 47Y-67L was associated with increased risk of NKTCL. These two positions are component parts of the peptide-binding pocket 7 (P7) of the HLA-DR heterodimer, suggesting that these alterations might account for the association at HLA-DRB1, independent of the previously reported HLA-DPB1 variants.
Our findings provide new insights into the development of NKTCL by showing the importance of inflammation and immune regulation through the IL18–IL18RAP axis and antigen presentation involving HLA-DRB1, which might help to identify potential therapeutic targets. Taken in combination with additional genetic and other risk factors, our results could potentially be used to stratify people at high risk of NKTCL for targeted prevention.
Guangdong Innovative and Entrepreneurial Research Team Program, National Natural Science Foundation of China, National Program for Support of Top-Notch Young Professionals, Chang Jiang Scholars Program, Singapore Ministry of Health's National Medical Research Council, Tanoto Foundation, National Research Foundation Singapore, Chang Gung Memorial Hospital, Recruitment Program for Young Professionals of China, First Affiliated Hospital and Army Medical University, US National Institutes of Health, and US National Cancer Institute.
Journal Article
A Clinico-Genotypic Prognostic Index for De Novo Composite Diffuse Large B-Cell Lymphoma Arising from Follicular Lymphoma in Asian patients treated in the Rituximab Era
by
Farid, Mohamad
,
Tao, Miriam
,
Somasundaram, Nagavalli
in
692/4028/67/1857
,
692/4028/67/1990/291/1621
,
692/4028/67/69
2020
Composite follicular lymphoma with diffuse large B-cell lymphoma (FL/DLBCL) is uncommonly found on lymph node biopsy and represents a rare haematological malignancy. We aim to examine clinico-pathological features of patients with FL/DLBCL and investigate predictors of survival outcome. We included in our retrospective study patients with histologically-proven FL/DLBCL at diagnosis (n = 106) and who were subsequently treated with rituximab-based chemoimmunotherapy from 2002–2017 at the National Cancer Centre. The cohort consisted of 34 women and 72 men with a median age of 59 years (range, 24–82). In a multivariate model inclusive of known clinico-pathological parameters at diagnosis, advanced stage (
p
= 0.0136), presence of
MYC
and/or
BCL6
rearrangement (
p
= 0.0376) and presence of B symptoms (
p
= 0.0405) were independently prognostic for worse overall survival (OS). The only remaining independent prognostic variables for worse OS after including first-line treatment data in the model were use of chemotherapy regimens other than R-CHOP (
p
= 0.0360) and lack of complete response to chemotherapy (
p
< 0.0001) besides the presence of B symptoms (
p
= 0.0022). We generated a Clinico-Genotypic Index by point-wise addition of all five adverse parameters (score of 0–1, 2, 3, 4–5) which revealed four prognostic risk groups with a predicted 5-year OS of 100%, 62%, 40% and 0% (
p
< 0.0001) accounting for 50.0%, 24.5%, 18.9% and 6.6% of the cohort respectively. We propose that R-CHOP should be the recommended first-line regimen for composite FL/DLBCL.
Journal Article
Intravascular Large B-cell Lymphoma in a Young Southeast Asian Male With Recurrent Strokes and Pulmonary Ground Glass Opacities With a Normal Chest Radiograph
2024
Intravascular large B-cell lymphoma (IVLBCL) is a rare form of extranodal large B-cell lymphoma characterized by the growth of lymphoma cells within lumina of blood vessels, especially capillaries, which aggregate to form clots, resulting in organ ischemia. In Caucasians, it predominantly involves the central nervous system (CNS) and the skin, with the cutaneous variant carrying a better prognosis. Whereas in Asians it preferentially involves the bone marrow, liver, and spleen and is associated with hemophagocytic syndrome. We report a case of a young Asian male with neurological, pulmonary, and hepatosplenic involvement. He presented with recurrent strokes, chronic cough, and unintentional weight loss. The chest radiograph (CXR) on admission was clear. Magnetic resonance imaging (MRI) of the brain showed acute multifocal infarcts, and a whole-body computed tomography (CT) scan revealed upper-lobe predominant pulmonary ground glass opacities (GGOs) with mediastinal lymphadenopathy. Interestingly, a CXR performed one week after the CT scan remained clear. The positron emission tomography-computed tomography (PET-CT) showed hepatosplenic and adrenal involvement. The diagnosis was confirmed via a bronchoscopic approach. The patient received chemotherapy consisting of MR-CHOP (methotrexate, rituximab, cyclophosphamide, adriamycin, vincristine, and prednisolone), high-dose methotrexate, and intrathecal cytarabine, which led to complete remission. Subsequently, he underwent an autologous peripheral blood stem cell transplant. At the time of writing this case report, the patient is still in complete remission for three years after the initial diagnosis. As IVLBCL has a non-specific clinicoradiological presentation, it is important to suspect IVLBCL in patients with an atypical neurological and pulmonary presentation in the presence of raised serum lactate dehydrogenase (LDH) and to consider a CT scan of the thorax if CXR is normal.
Journal Article
Artificial intelligence modelling in differentiating core biopsies of fibroadenoma from phyllodes tumor
2022
Breast fibroepithelial lesions (FEL) are biphasic tumors which consist of benign fibroadenomas (FAs) and the rarer phyllodes tumors (PTs). FAs and PTs have overlapping features, but have different clinical management, which makes correct core biopsy diagnosis important. This study used whole-slide images (WSIs) of 187 FA and 100 PT core biopsies, to investigate the potential role of artificial intelligence (AI) in FEL diagnosis. A total of 9228 FA patches and 6443 PT patches was generated from WSIs of the training subset, with each patch being 224 × 224 pixel in size. Our model employed a two-stage architecture comprising a convolutional neural network (CNN) component for feature extraction from the patches, and a recurrent neural network (RNN) component for whole-slide classification using activation values from the global average pooling layer in the CNN model. It achieved an overall slide-level accuracy of 87.5%, with accuracies of 80% and 95% for FA and PT slides respectively. This affirms the potential role of AI in diagnostic discrimination between FA and PT on core biopsies which may be further refined for use in routine practice.
An artificial intelligence (AI) model was developed to discriminate between fibroadenomas and phyllodes tumors on core biopsy images. It employed a two-stage architecture comprising a convolutional neural network (CNN) component for feature extraction, and a recurrent neural network (RNN) component for whole-slide classification, with an overall slide-level accuracy of 87.5%.
Journal Article
Expression of FGFR1 is an independent prognostic factor in triple-negative breast cancer
2015
Triple-negative breast cancers (TNBCs) are clinically aggressive tumors with limited treatment options. We examined the clinicopathological associations and prognostic implications of FGFR1 and FGFR2 expression in TNBCs. Tissue microarrays constructed from TNBCs were immunostained with FGFR1 and FGFR2, and scored by intensity and percentage of tumor cells stained per intensity for each subcellular compartment, which were correlated with clinicopathological parameters and survival. Cell migration following siRNA-mediated silencing of the
FGFR1
gene in TNBC cell lines was also performed. 714 cases were informative for FGFR1 and FGFR2 immunostaining. Thresholds were defined as at least 1 % of cells stained and H-score of 100 or more. Proportions positive by each threshold were, respectively, 89.9 %, 7.1 % for FGFR1 (cytoplasm); 36.8 %, 7.8 % for FGFR2 (cytoplasm); and 33.5 %, 5.2 % for FGFR2 (membrane). Significant associations included FGFR1 and FGFR2 immunostaining for lobular subtype, FGFR2 immunostaining with lower grade, and more basal-like cancers with H-scores of 100 or more FGFR1 immunostaining. Multivariate Cox regression analysis showed FGFR1 expression in TNBCs to be independently prognostic for overall survival (OS) at both thresholds. Cases completely negative (less than 1 % staining) for FGFR1 immunostaining showed improved OS, while those with H-score of 100 or more immunostaining had the worst OS. Cell line studies revealed up-regulation of the
FGFR1
gene in the MDA-MB-231 and Hs578T TNBC cells, and specific knockdown of FGFR1 expression significantly reduced cell migration in MDA-MB-231 cell line. In conclusion, FGFR1 expression in TNBCs is independently prognostic of OS, and H-score of 100 or more FGFR1 immunostaining may define tumors that have treatment potential via FGFR signaling inhibition.
Journal Article
A clinicohaematological prognostic model for nasal-type natural killer/T-cell lymphoma: A multicenter study
by
Huang, Dachuan
,
Kim, Seok Jin
,
Tan, Jing
in
38/39
,
631/67/1990/291/1621/1916
,
692/4028/67/1990/291/1621/1916
2019
Extranodal NK/T-cell lymphoma, nasal type (NKTL) is an aggressive type of non-Hodgkin lymphoma closely associated with Epstein-Barr virus and characterized by varying degrees of systemic inflammation. We aim to examine the prognostic significance of peripheral blood neutrophil-lymphocyte ratio (NLR) in patients with NKTL. Therefore, we conducted a retrospective review of 178 patients with biopsy-proven NKTL from the National Cancer Centre Singapore and Samsung Medical Center, South Korea. Using receiver operating curve analysis, an optimal cut-off for high NLR (>3.5) in predicting overall survival (OS) was derived. Survival analysis was performed using the Kaplan-Meier method and multivariable Cox proportional regression. In patients with high NLR, estimated 5-year OS was 25% compared to 53% in those with low NLR. In multivariable analysis, high NLR, in addition to age ≥60 years, presence of B-symptoms and stage III/IV at diagnosis, was independently correlated with worse OS (HR 2.08; 95% CI 1.36 to 3.18;
p
= 0.0008) and progression-free survival (HR 1.66; 95% CI 1.11 to 2.46;
p
= 0.0128). A new prognostic index (NABS score) derived from these factors stratified patients into low (0), low-intermediate (1), high-intermediate (2) and high (3–4) risk subgroups, which were associated with 5-year OS of 76.5%, 55.7%, 29.2% and 0% respectively. In conclusion, high NLR is an independent prognostic marker and the NABS model can be used to risk-stratify NKTL patients.
Journal Article
T-Cell Lymphoma Clonality by Copy Number Variation Analysis of T-Cell Receptor Genes
2021
T-cell lymphomas arise from a single neoplastic clone and exhibit identical patterns of deletions in T-cell receptor (TCR) genes. Whole genome sequencing (WGS) data represent a treasure trove of information for the development of novel clinical applications. However, the use of WGS to identify clonal T-cell proliferations has not been systematically studied. In this study, based on WGS data, we identified monoclonal rearrangements (MRs) of T-cell receptors (TCR) genes using a novel segmentation algorithm and copy number computation. We evaluated the feasibility of this technique as a marker of T-cell clonality using T-cell lymphomas (TCL, n = 44) and extranodal NK/T-cell lymphomas (ENKTLs, n = 20), and identified 98% of TCLs with one or more TCR gene MRs, against 91% detected using PCR. TCR MRs were absent in all ENKTLs and NK cell lines. Sensitivity-wise, this platform is sufficiently competent, with MRs detected in the majority of samples with tumor content under 25% and it can also distinguish monoallelic from biallelic MRs. Understanding the copy number landscape of TCR using WGS data may engender new diagnostic applications in hematolymphoid pathology, which can be readily adapted to the analysis of B-cell receptor loci for B-cell clonality determination.
Journal Article
Digital pathology in the diagnostic setting: beyond technology into best practice and service management
by
Tan, Puay Hoon
,
Cheng, Chee Leong
in
Humans
,
Image Interpretation, Computer-Assisted - methods
,
Laboratories - organization & administration
2017
Digital pathology (DP) and whole-slide imaging (WSI) technology have matured substantially over the last few years and there is growing evidence from validation studies that WSI is comparable to glass slides for histopathology diagnosis, although with some limitations, which can be appropriately minimised. Whether the controlled environment of validation studies translates to the same level of robustness when WSI is used in the actual diagnostic setting depends on the technical quality of WSI acquisition and on factors that influence the pre-image acquisition variables including the quality of glass slide inputs, and postimage acquisition variables such as access and use of WSI. The concept of ‘DP service management’ is introduced to fulfil the holistic needs of a laboratory intending to use the DP solution incorporating WSI for diagnostic purposes. The DP service management team should be an integral part of the diagnostic laboratory as it plays a central role undertaking responsibility to address an extensive range of issues from technical and training to governance and accreditation, hence ensuring a viable and sustainable diagnostic DP integration and usage. The pathologist as a specialist in the field and key decision maker of histopathology diagnoses has the duty and responsibility to acquaint and familiarise with DP and WSI when using the technology, especially on their indications and limitations, so as to take full advantage of these tools to enhance diagnostic quality.
Journal Article