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Hung TH, Wu ETY, Zeltiņš P, Jansons Ā, Ullah A, Erbilgin N, Bohlmann J, Bousquet J, Birol I, Clegg SM, MacKay JJ. Long-insert sequence capture detects high copy numbers in a defence-related beta-glucosidase gene βglu-1 with large variations in white spruce but not Norway spruce. BMC Genomics 2024; 25:118. [PMID: 38281030 PMCID: PMC10821269 DOI: 10.1186/s12864-024-09978-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 01/05/2024] [Indexed: 01/29/2024] Open
Abstract
Conifers are long-lived and slow-evolving, thus requiring effective defences against their fast-evolving insect natural enemies. The copy number variation (CNV) of two key acetophenone biosynthesis genes Ugt5/Ugt5b and βglu-1 may provide a plausible mechanism underlying the constitutively variable defence in white spruce (Picea glauca) against its primary defoliator, spruce budworm. This study develops a long-insert sequence capture probe set (Picea_hung_p1.0) for quantifying copy number of βglu-1-like, Ugt5-like genes and single-copy genes on 38 Norway spruce (Picea abies) and 40 P. glauca individuals from eight and nine provenances across Europe and North America respectively. We developed local assemblies (Piabi_c1.0 and Pigla_c.1.0), full-length transcriptomes (PIAB_v1 and PIGL_v1), and gene models to characterise the diversity of βglu-1 and Ugt5 genes. We observed very large copy numbers of βglu-1, with up to 381 copies in a single P. glauca individual. We observed among-provenance CNV of βglu-1 in P. glauca but not P. abies. Ugt5b was predominantly single-copy in both species. This study generates critical hypotheses for testing the emergence and mechanism of extreme CNV, the dosage effect on phenotype, and the varying copy number of genes with the same pathway. We demonstrate new approaches to overcome experimental challenges in genomic research in conifer defences.
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Affiliation(s)
- Tin Hang Hung
- Department of Biology, University of Oxford, Oxford, OX1 3RB, UK.
| | - Ernest T Y Wu
- Department of Biology, University of Oxford, Oxford, OX1 3RB, UK
| | - Pauls Zeltiņš
- Latvian State Forest Research Institute "Silava", Salaspils, 2169, Latvia
| | - Āris Jansons
- Latvian State Forest Research Institute "Silava", Salaspils, 2169, Latvia
| | - Aziz Ullah
- Department of Renewable Resources, University of Alberta, Edmonton, AB, T6G 2E3, Canada
| | - Nadir Erbilgin
- Department of Renewable Resources, University of Alberta, Edmonton, AB, T6G 2E3, Canada
| | - Joerg Bohlmann
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Jean Bousquet
- Canada Research Chair in Forest Genomics, Forest Research Centre, Université Laval, Québec, QC, G1V 0A6, Canada
| | - Inanc Birol
- Canada's Michael Smith Genome Sciences Centre, BC Cancer Agency, Vancouver, BC, V5Z 4S6, Canada
| | - Sonya M Clegg
- Department of Biology, University of Oxford, Oxford, OX1 3RB, UK
| | - John J MacKay
- Department of Biology, University of Oxford, Oxford, OX1 3RB, UK.
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Su WC, Mao XM, Li SY, Luo CY, Fan R, Jiang HF, Zhang LJ, Wang YT, Su GQ, Shen DY. DPY30 Promotes Proliferation and Cell Cycle Progression of Colorectal Cancer Cells via Mediating H3K4 Trimethylation. Int J Med Sci 2023; 20:901-917. [PMID: 37324189 PMCID: PMC10266052 DOI: 10.7150/ijms.80073] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 03/25/2023] [Indexed: 06/17/2023] Open
Abstract
DPY30, a core subunit of the SET1/MLL histone H3K4 methyltransferase complexes, plays an important role in diverse biological functions through the epigenetic regulation of gene transcription, especially in cancer development. However, its involvement in human colorectal carcinoma (CRC) has not been elucidated yet. Here we demonstrated that DPY30 was overexpressed in CRC tissues, and significantly associated with pathological grading, tumor size, TNM stage, and tumor location. Furthermore, DPY30 knockdown remarkably suppressed the CRC cell proliferation through downregulation of PCNA and Ki67 in vitro and in vivo, simultaneously induced cell cycle arrest at S phase by downregulating Cyclin A2. In the mechanistic study, RNA-Seq analysis revealed that enriched gene ontology of cell proliferation and cell growth was significantly affected. And ChIP result indicated that DPY30 knockdown inhibited H3 lysine 4 trimethylation (H3K4me3) and attenuated interactions between H3K4me3 with PCNA, Ki67 and cyclin A2 respectively, which led to the decrease of H3K4me3 establishment on their promoter regions. Taken together, our results demonstrate overexpression of DPY30 promotes CRC cell proliferation and cell cycle progression by facilitating the transcription of PCNA, Ki67 and cyclin A2 via mediating H3K4me3. It suggests that DPY30 may serve as a potential therapeutic molecular target for CRC.
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Affiliation(s)
- Wei-Chao Su
- Department of Colorectal Tumor Surgery, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361003, Fujian Province, P.R. China
| | - Xiao-Mei Mao
- School of Pharmaceutical Science and Technology, Suzhou Chien-Shiung Institute of Technology, Suzhou 215411, Jiangsu Province, P.R. China
| | - Si-Yang Li
- Xiamen Cell Therapy Research Center, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361003, Fujian Province, P.R. China
| | - Chun-Ying Luo
- Department of Pathology, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise 533000, Guangxi Province, P.R. China
- Medical College, Guangxi University, Nanning 530004, Guangxi Province, P.R. China
| | - Rui Fan
- Xiamen Cell Therapy Research Center, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361003, Fujian Province, P.R. China
| | - Hai-Feng Jiang
- Department of Colorectal Tumor Surgery, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361003, Fujian Province, P.R. China
| | - Lin-Jun Zhang
- Xiamen Cell Therapy Research Center, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361003, Fujian Province, P.R. China
| | - Ya-Tao Wang
- Department of Colorectal Tumor Surgery, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361003, Fujian Province, P.R. China
| | - Guo-Qiang Su
- Department of Colorectal Tumor Surgery, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361003, Fujian Province, P.R. China
- Medical College, Guangxi University, Nanning 530004, Guangxi Province, P.R. China
| | - Dong-Yan Shen
- Xiamen Cell Therapy Research Center, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361003, Fujian Province, P.R. China
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Qian SH, Chen L, Xiong YL, Chen ZX. Evolution and function of developmentally dynamic pseudogenes in mammals. Genome Biol 2022; 23:235. [PMID: 36348461 PMCID: PMC9641868 DOI: 10.1186/s13059-022-02802-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 10/23/2022] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Pseudogenes are excellent markers for genome evolution, which are emerging as crucial regulators of development and disease, especially cancer. However, systematic functional characterization and evolution of pseudogenes remain largely unexplored. RESULTS To systematically characterize pseudogenes, we date the origin of human and mouse pseudogenes across vertebrates and observe a burst of pseudogene gain in these two lineages. Based on a hybrid sequencing dataset combining full-length PacBio sequencing, sample-matched Illumina sequencing, and public time-course transcriptome data, we observe that abundant mammalian pseudogenes could be transcribed, which contribute to the establishment of organ identity. Our analyses reveal that developmentally dynamic pseudogenes are evolutionarily conserved and show an increasing weight during development. Besides, they are involved in complex transcriptional and post-transcriptional modulation, exhibiting the signatures of functional enrichment. Coding potential evaluation suggests that 19% of human pseudogenes could be translated, thus serving as a new way for protein innovation. Moreover, pseudogenes carry disease-associated SNPs and conduce to cancer transcriptome perturbation. CONCLUSIONS Our discovery reveals an unexpectedly high abundance of mammalian pseudogenes that can be transcribed and translated, and these pseudogenes represent a novel regulatory layer. Our study also prioritizes developmentally dynamic pseudogenes with signatures of functional enrichment and provides a hybrid sequencing dataset for further unraveling their biological mechanisms in organ development and carcinogenesis in the future.
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Affiliation(s)
- Sheng Hu Qian
- grid.35155.370000 0004 1790 4137Hubei Hongshan Laboratory, College of Biomedicine and Health, Huazhong Agricultural University, Wuhan, 430070 PR China ,grid.35155.370000 0004 1790 4137Hubei Key Laboratory of Agricultural Bioinformatics, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070 PR China
| | - Lu Chen
- grid.35155.370000 0004 1790 4137Hubei Hongshan Laboratory, College of Biomedicine and Health, Huazhong Agricultural University, Wuhan, 430070 PR China ,grid.35155.370000 0004 1790 4137Hubei Key Laboratory of Agricultural Bioinformatics, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070 PR China
| | - Yu-Li Xiong
- grid.35155.370000 0004 1790 4137Hubei Hongshan Laboratory, College of Biomedicine and Health, Huazhong Agricultural University, Wuhan, 430070 PR China ,grid.35155.370000 0004 1790 4137Hubei Key Laboratory of Agricultural Bioinformatics, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070 PR China
| | - Zhen-Xia Chen
- grid.35155.370000 0004 1790 4137Hubei Hongshan Laboratory, College of Biomedicine and Health, Huazhong Agricultural University, Wuhan, 430070 PR China ,grid.35155.370000 0004 1790 4137Hubei Key Laboratory of Agricultural Bioinformatics, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070 PR China ,grid.35155.370000 0004 1790 4137Interdisciplinary Sciences Institute, Huazhong Agricultural University, Wuhan, 430070 PR China ,grid.35155.370000 0004 1790 4137Shenzhen Institute of Nutrition and Health, Huazhong Agricultural University, Shenzhen, 518124 PR China ,grid.488316.00000 0004 4912 1102Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518124 PR China
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Zeng Z, Gao Y, Li J, Zhang G, Sun S, Wu Q, Gong Y, Xie C. Violations of proportional hazard assumption in Cox regression model of transcriptomic data in TCGA pan-cancer cohorts. Comput Struct Biotechnol J 2022; 20:496-507. [PMID: 35070171 PMCID: PMC8762368 DOI: 10.1016/j.csbj.2022.01.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 01/03/2022] [Accepted: 01/03/2022] [Indexed: 11/29/2022] Open
Abstract
Background Cox proportional hazard regression (CPH) model relies on the proportional hazard (PH) assumption: the hazard of variables is independent of time. CPH has been widely used to identify prognostic markers of the transcriptome. However, the comprehensive investigation on PH assumption in transcriptomic data has lacked. Results The whole transcriptomic data of the 9,056 patients from 32 cohorts of The Cancer Genome Atlas and the 3 lung cancer cohorts from Gene Expression Omnibus were collected to construct CPH model for each gene separately for fitting the overall survival. An average of 8.5% gene CPH models violated the PH assumption in TCGA pan-cancer cohorts. In the gene interaction networks, both hub and non-hub genes in CPH models were likely to have non-proportional hazards. Violations of PH assumption for the same gene models were not consistent in 5 non-small cell lung cancer datasets (all kappa coefficients < 0.2), indicating that the non-proportionality of gene CPH models depended on the datasets. Furthermore, the introduction of log(t) or sqrt(t) time-functions into CPH improved the performance of gene models on overall survival fitting in most tumors. The time-dependent CPH changed the significance of log hazard ratio of the 31.9% gene variables. Conclusions Our analysis resulted that non-proportional hazards should not be ignored in transcriptomic data. Introducing time interaction term ameliorated performance and interpretability of non-proportional hazards of transcriptome data in CPH.
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Key Words
- ACC, Adrenocortical carcinoma
- AIC, Akaike information criterion
- BLCA, Bladder Urothelial Carcinoma
- BRCA, Breast invasive carcinoma
- CESC, Cervical squamous cell carcinoma and endocervical adenocarcinoma
- CHOL, Cholangiocarcinoma
- COAD, Colon adenocarcinoma
- CON, Concordance regression
- CPH, Cox proportional hazard regression
- Cox regression
- DLBC, Lymphoid Neoplasm Diffuse Large B-cell Lymphoma
- ESCA, Esophageal carcinoma
- GBM, Glioblastoma multiforme
- GEO, Gene Expression Omnibus
- GO, Gene Ontology
- HNSC, Head and Neck squamous cell carcinoma
- KICH, Kidney Chromophobe
- KIRC, Kidney renal clear cell carcinoma
- KIRP, Kidney renal papillary cell carcinoma
- LGG, Brain Lower Grade Glioma
- LIHC, Liver hepatocellular carcinoma
- LUAD, Lung adenocarcinoma
- LUSC, Lung squamous cell carcinoma
- MESO, Mesothelioma
- OS, overall survival
- OV, Ovarian serous cystadenocarcinoma
- PAAD, Pancreatic adenocarcinoma
- PCPG, Pheochromocytoma and Paraganglioma
- PH, proportional hazard
- PRAD, Prostate adenocarcinoma
- Pan-cancer
- Proportional hazard assumption
- READ, Rectum adenocarcinoma
- SARC, Sarcoma
- SKCM, Skin Cutaneous Melanoma
- STAD, Stomach adenocarcinoma
- TCGA
- TCGA, The Cancer Genome Atlas
- TCGA, tumor abbreviations
- TGCT, Testicular Germ Cell Tumors
- THCA, Thyroid carcinoma
- THYM, Thymoma
- Transcriptome
- UCEC, Uterine Corpus Endometrial Carcinoma
- UCS, Uterine Carcinosarcoma
- UVM, Uveal Melanoma
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Affiliation(s)
- Zihang Zeng
- Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Yanping Gao
- Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Jiali Li
- Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Gong Zhang
- Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Shaoxing Sun
- Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Qiuji Wu
- Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Yan Gong
- Department of Biological Repositories, Zhongnan Hospital of Wuhan University, Wuhan, China.,Tumor Precision Diagnosis and Treatment Technology and Translational Medicine, Hubei Engineering Research Center, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Conghua Xie
- Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan, China.,Hubei Key Laboratory of Tumor Biological Behaviors, Zhongnan Hospital of Wuhan University, Wuhan, China.,Hubei Cancer Clinical Study Center, Zhongnan Hospital of Wuhan University, Wuhan, China
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Yu Y, Werdyani S, Carey M, Parfrey P, Yilmaz YE, Savas S. A comprehensive analysis of SNPs and CNVs identifies novel markers associated with disease outcomes in colorectal cancer. Mol Oncol 2021; 15:3329-3347. [PMID: 34309201 PMCID: PMC8637572 DOI: 10.1002/1878-0261.13067] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 05/29/2021] [Accepted: 07/24/2021] [Indexed: 12/15/2022] Open
Abstract
We aimed to examine the associations of a genome-wide set of single nucleotide polymorphisms (SNPs) and 254 copy number variations (CNVs) and/or insertion/deletions (INDELs) with clinical outcomes in colorectal cancer patients (n = 505). We also aimed to investigate whether their associations changed (e.g., appeared, diminished) over time. Multivariable Cox proportional hazards and piece-wise Cox regression models were used to examine the associations. The Cancer Genome Atlas (TCGA) datasets were used for replication purposes and to examine the gene expression differences between tumor and nontumor tissue samples. A common SNP (WBP11-rs7314075) was associated with disease-specific survival with P-value of 3.2 × 10-8 . Association of this region with disease-specific survival was also detected in the TCGA patient cohort. Two expression quantitative trait loci (eQTLs) were identified in this locus that were implicated in the regulation of ERP27 expression. Interestingly, expression levels of ERP27 and WBP11 were significantly different between colorectal tumors and nontumor tissues. Three SNPs predicted the risk of recurrent disease only after 5 years postdiagnosis. Overall, our study identified novel variants, one of which also showed an association in the TCGA dataset, but no CNVs/INDELs, that associated with outcomes in colorectal cancer. Three SNPs were candidate predictors of long-term recurrence/metastasis risk.
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Affiliation(s)
- Yajun Yu
- Discipline of GeneticsFaculty of MedicineMemorial UniversitySt. John’sNLCanada
- Present address:
Division of Biomedical SciencesFaculty of MedicineMemorial UniversitySt. John’sNLCanada
| | - Salem Werdyani
- Discipline of GeneticsFaculty of MedicineMemorial UniversitySt. John’sNLCanada
- Present address:
Division of Biomedical SciencesFaculty of MedicineMemorial UniversitySt. John’sNLCanada
| | - Megan Carey
- Discipline of GeneticsFaculty of MedicineMemorial UniversitySt. John’sNLCanada
| | - Patrick Parfrey
- Discipline of MedicineFaculty of MedicineMemorial UniversitySt. John’sNLCanada
| | - Yildiz E. Yilmaz
- Discipline of GeneticsFaculty of MedicineMemorial UniversitySt. John’sNLCanada
- Discipline of MedicineFaculty of MedicineMemorial UniversitySt. John’sNLCanada
- Department of Mathematics and StatisticsFaculty of ScienceMemorial UniversitySt. John’sNLCanada
| | - Sevtap Savas
- Discipline of GeneticsFaculty of MedicineMemorial UniversitySt. John’sNLCanada
- Discipline of OncologyFaculty of MedicineMemorial UniversitySt. John’sNLCanada
- Present address:
Division of Biomedical SciencesFaculty of MedicineMemorial UniversitySt. John’sNLCanada
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Rafter P, Gormley IC, Parnell AC, Naderi S, Berry DP. The Contribution of Copy Number Variants and Single Nucleotide Polymorphisms to the Additive Genetic Variance of Carcass Traits in Cattle. Front Genet 2021; 12:761503. [PMID: 34795696 PMCID: PMC8593468 DOI: 10.3389/fgene.2021.761503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 10/04/2021] [Indexed: 11/13/2022] Open
Abstract
The relative contributions of both copy number variants (CNVs) and single nucleotide polymorphisms (SNPs) to the additive genetic variance of carcass traits in cattle is not well understood. A detailed understanding of the relative importance of CNVs in cattle may have implications for study design of both genomic predictions and genome-wide association studies. The first objective of the present study was to quantify the relative contributions of CNV data and SNP genotype data to the additive genetic variance of carcass weight, fat, and conformation for 945 Charolais, 923 Holstein-Friesian, and 974 Limousin sires. The second objective was to jointly consider SNP and CNV data in a least absolute selection and shrinkage operator (LASSO) regression model to identify genomic regions associated with carcass weight, fat, and conformation within each of the three breeds separately. A genomic relationship matrix (GRM) based on just CNV data did not capture any variance in the three carcass traits when jointly evaluated with a SNP-derived GRM. In the LASSO regression analysis, a total of 987 SNPs and 18 CNVs were associated with at least one of the three carcass traits in at least one of the three breeds. The quantitative trait loci (QTLs) corresponding to the associated SNPs and CNVs overlapped with several candidate genes including previously reported candidate genes such as MSTN and RSAD2, and several potential novel candidate genes such as ACTN2 and THOC1. The results of the LASSO regression analysis demonstrated that CNVs can be used to detect associations with carcass traits which were not detected using the set of SNPs available in the present study. Therefore, the CNVs and SNPs available in the present study were not redundant forms of genomic data.
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Affiliation(s)
- Pierce Rafter
- Animal & Grassland Research and Innovation Centre, Fermoy, Ireland.,School of Mathematics and Statistics, University College Dublin, Dublin, Ireland
| | | | | | - Saeid Naderi
- Irish Cattle Breeding Federation, Bandon, Ireland
| | - Donagh P Berry
- Animal & Grassland Research and Innovation Centre, Fermoy, Ireland
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Chen S, Lu L, Xian J, Shi C, Chen J, Rao B, Qiu F, Lu J, Yang L. Prognostic Value of Germline Copy Number Variants and Environmental Exposures in Non-small Cell Lung Cancer. Front Genet 2021; 12:681857. [PMID: 34178039 PMCID: PMC8226327 DOI: 10.3389/fgene.2021.681857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 05/18/2021] [Indexed: 11/13/2022] Open
Abstract
Germline copy number variant (gCNV) has been studied as a genetic determinant for prognosis of several types of cancer, but little is known about how it affects non-small cell lung cancer (NSCLC) prognosis. We aimed to develop a prognostic nomogram for NSCLC based on gCNVs. Promising gCNVs that are associated with overall survival (OS) of NSCLC were sorted by analyzing the TCGA data and were validated in a small Chinese population. Then the successfully verified gCNVs were determined in a training cohort (n = 570) to develop a prognostic nomogram, and in a validation cohort (n = 465) to validate the nomogram. Thirty-five OS-related gCNVs were sorted and were reduced to 15 predictors by the Lasso regression analysis. Of them, only CNVR395.1 and CNVR2239.1 were confirmed to be associated with OS of NSCLC in the Chinese population. High polygenic risk score (PRS), which was calculated by the hazard effects of CNVR395.1 and CNVR2239.1, exerted a significantly higher death rate in the training cohort (HR = 1.41, 95%CI: 1.16-1.74) and validation cohort (HR = 1.42, 95%CI: 1.13-1.77) than low PRS. The nomogram incorporating PRS and surrounding factors, achieved admissible concordance indexes of 0.678 (95%CI: 0.664-0.693) and 0.686 (95%CI: 0.670-0.702) in predicting OS in the training and validation cohorts, respectively, and had well-fitted calibration curves. Moreover, an interaction between PRS and asbestos exposure was observed on affecting OS (P interaction = 0.042). Our analysis developed a nomogram that achieved an admissible prediction of NSCLC survival, which would be beneficial to the personalized intervention of NSCLC.
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Affiliation(s)
- Shizhen Chen
- The State Key Laboratory of Respiratory Disease, Institute of Public Health, Guangzhou Medical University, Guangzhou, China
| | - Liming Lu
- The State Key Laboratory of Respiratory Disease, Institute of Public Health, Guangzhou Medical University, Guangzhou, China
| | - Jianfeng Xian
- The State Key Laboratory of Respiratory Disease, Institute of Public Health, Guangzhou Medical University, Guangzhou, China
| | - Changhong Shi
- The State Key Laboratory of Respiratory Disease, Institute of Public Health, Guangzhou Medical University, Guangzhou, China
| | - Jinbin Chen
- The State Key Laboratory of Respiratory Disease, Institute of Public Health, Guangzhou Medical University, Guangzhou, China
| | - Boqi Rao
- The State Key Laboratory of Respiratory Disease, Institute of Public Health, Guangzhou Medical University, Guangzhou, China
| | - Fuman Qiu
- The State Key Laboratory of Respiratory Disease, Institute of Public Health, Guangzhou Medical University, Guangzhou, China
| | - Jiachun Lu
- The State Key Laboratory of Respiratory Disease, Institute of Public Health, Guangzhou Medical University, Guangzhou, China
- The State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Lei Yang
- The State Key Laboratory of Respiratory Disease, Institute of Public Health, Guangzhou Medical University, Guangzhou, China
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8
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Copy number variation: Characteristics, evolutionary and pathological aspects. Biomed J 2021; 44:548-559. [PMID: 34649833 PMCID: PMC8640565 DOI: 10.1016/j.bj.2021.02.003] [Citation(s) in RCA: 73] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 02/01/2021] [Accepted: 02/05/2021] [Indexed: 12/12/2022] Open
Abstract
Copy number variants (CNVs) were the subject of extensive research in the past years. They are common features of the human genome that play an important role in evolution, contribute to population diversity, development of certain diseases, and influence host–microbiome interactions. CNVs have found application in the molecular diagnosis of many diseases and in non-invasive prenatal care, but their full potential is only emerging. CNVs are expected to have a tremendous impact on screening, diagnosis, prognosis, and monitoring of several disorders, including cancer and cardiovascular disease. Here, we comprehensively review basic definitions of the term CNV, outline mechanisms and factors involved in CNV formation, and discuss their evolutionary and pathological aspects. We suggest a need for better defined distinguishing criteria and boundaries between known types of CNVs.
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Concordance rate between copy number variants detected using either high- or medium-density single nucleotide polymorphism genotype panels and the potential of imputing copy number variants from flanking high density single nucleotide polymorphism haplotypes in cattle. BMC Genomics 2020; 21:205. [PMID: 32131735 PMCID: PMC7057620 DOI: 10.1186/s12864-020-6627-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 02/26/2020] [Indexed: 12/01/2022] Open
Abstract
Background The trading of individual animal genotype information often involves only the exchange of the called genotypes and not necessarily the additional information required to effectively call structural variants. The main aim here was to determine if it is possible to impute copy number variants (CNVs) using the flanking single nucleotide polymorphism (SNP) haplotype structure in cattle. While this objective was achieved using high-density genotype panels (i.e., 713,162 SNPs), a secondary objective investigated the concordance of CNVs called with this high-density genotype panel compared to CNVs called from a medium-density panel (i.e., 45,677 SNPs in the present study). This is the first study to compare CNVs called from high-density and medium-density SNP genotypes from the same animals. High (and medium-density) genotypes were available on 991 Holstein-Friesian, 1015 Charolais, and 1394 Limousin bulls. The concordance between CNVs called from the medium-density and high-density genotypes were calculated separately for each animal. A subset of CNVs which were called from the high-density genotypes was selected for imputation. Imputation was carried out separately for each breed using a set of high-density SNPs flanking the midpoint of each CNV. A CNV was deemed to be imputed correctly when the called copy number matched the imputed copy number. Results For 97.0% of CNVs called from the high-density genotypes, the corresponding genomic position on the medium-density of the animal did not contain a called CNV. The average accuracy of imputation for CNV deletions was 0.281, with a standard deviation of 0.286. The average accuracy of imputation of the CNV normal state, i.e. the absence of a CNV, was 0.982 with a standard deviation of 0.022. Two CNV duplications were imputed in the Charolais, a single CNV duplication in the Limousins, and a single CNV duplication in the Holstein-Friesians; in all cases the CNV duplications were incorrectly imputed. Conclusion The vast majority of CNVs called from the high-density genotypes were not detected using the medium-density genotypes. Furthermore, CNVs cannot be accurately predicted from flanking SNP haplotypes, at least based on the imputation algorithms routinely used in cattle, and using the SNPs currently available on the high-density genotype panel.
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Hayes IP, Milanzi E, Gibbs P, Reece JC. Neoadjuvant Chemoradiotherapy and Tumor Recurrence in Patients with Early T-Stage Cancer of the Lower Rectum. Ann Surg Oncol 2019; 27:1570-1579. [PMID: 31773520 DOI: 10.1245/s10434-019-08105-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND The role neoadjuvant chemoradiotherapy (nCRT) plays in oncological outcomes in early T-stage rectal cancer is uncertain. The present work aims to clarify prognostic outcomes by estimating the effect of nCRT on tumor recurrence prior to major surgery compared with major surgery alone. PATIENTS AND METHODS Prospectively collected data were retrospectively analyzed for patients diagnosed with localized rectal adenocarcinoma ≤ 8 cm from the anal verge, with final histopathology ≤ T2 (≤ ypT2/≤ pT2), regardless of magnetic resonance imaging staging, between 1990 and 2017. As the effect of nCRT on recurrence varied over time, thereby violating the Cox proportional hazards assumption, the effect of nCRT on recurrence hazards was estimated using a time-varying multivariate Cox model over two separate time intervals (≤ 1 year and > 1 year postsurgery) by nCRT. RESULTS Long-course nCRT was associated with a 5.6-fold increase in the hazard of recurrence ≤ 1 year postsurgery [hazard ratio (HR) 5.6; 95% confidence interval (CI) 1.2-24.9; P = 0.02], but there was no increase in recurrence hazards > 1 year (HR 0.84; 95% CI 0.4-2.0; P = 0.70). In subgroup analysis restricted to ≤ mrT2/≤ ypT2 and ≤ pT2 tumors (omitting > mrT2 tumors), the effect of nCRT on recurrence no longer varied over time, indicating that tumor heterogeneity was responsible for the observed increased recurrence hazards ≤ 1 year postsurgery; That is, > mrT2 tumors that were downstaged to ≤ ypT2 after nCRT were responsible for the time-varying effects of nCRT and increased recurrence hazards ≤ 1 year postsurgery. Subsequently, no difference was found in prognostic outcomes either with or without nCRT before surgery in the homogeneous population of ≤ mrT2/≤ ypT2 and ≤ pT2 tumors. CONCLUSIONS No evidence was found to indicate that nCRT prior to surgery reduces tumor recurrence in early T-stage lower rectal cancer compared with surgery alone.
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Affiliation(s)
- Ian P Hayes
- Colorectal Surgery Unit, Suite 2, Private Medical Centre, Royal Melbourne Hospital, Parkville, VIC, Australia. .,Department of Surgery, The University of Melbourne, Parkville, VIC, Australia.
| | - Elasma Milanzi
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, VIC, Australia.,Victorian Centre for Biostatistics, Melbourne, VIC, Australia
| | - Peter Gibbs
- Personalised Oncology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, VIC, Australia.,Department of Medical Oncology, Western Health, Melbourne, VIC, Australia
| | - Jeanette C Reece
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, VIC, Australia.,The University of Melbourne Centre for Cancer Research, The University of Melbourne, Parkville, VIC, Australia
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11
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Yu Y, Carey M, Pollett W, Green J, Dicks E, Parfrey P, Yilmaz YE, Savas S. The long-term survival characteristics of a cohort of colorectal cancer patients and baseline variables associated with survival outcomes with or without time-varying effects. BMC Med 2019; 17:150. [PMID: 31352904 PMCID: PMC6661748 DOI: 10.1186/s12916-019-1379-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 06/27/2019] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Colorectal cancer is the third most common cancer in the world. In this study, we assessed the long-term survival characteristics and prognostic associations and potential time-varying effects of clinico-demographic variables and two molecular markers (microsatellite instability (MSI) and BRAF Val600Glu mutation) in a population-based patient cohort followed up to ~ 19 years. METHODS The patient cohort included 738 incident cases diagnosed between 1999 and 2003. Cox models were used to analyze the association between the variables and a set of survival outcome measures (overall survival (OS), disease-specific survival (DSS), recurrence-free survival (RFS), metastasis-free survival (MFS), recurrence/metastasis-free survival (RMFS), and event-free survival (EFS)). Cox proportional hazard (PH) assumption was tested for all variables, and Cox models with time-varying effects were used if any departure from the PH assumption was detected. RESULTS During the follow-up, ~ 61% patients died from any cause, ~ 26% died from colorectal cancer, and ~ 10% and ~ 20% experienced recurrences and distant metastases, respectively. Stage IV disease and post-diagnostic recurrence or metastasis were strongly linked to risk of death from colorectal cancer. If a patient had survived the first 6 years without any disease-related event (i.e., recurrence, metastasis, or death from colorectal cancer), their risks became very minimal after this time period. Distinct sets of markers were associated with different outcome measures. In some cases, the effects by variables were constant throughout the follow-up. For example, MSI-high tumor phenotype and older age at diagnosis predicted longer MFS times consistently over the follow-up. However, in some other cases, the effects of the variables varied with time. For example, adjuvant radiotherapy treatment was associated with increased risk of metastasis in patients who received this treatment after 5.5 years post-diagnosis, but not before that. CONCLUSIONS This study describes the long-term survival characteristics of a prospective cohort of colorectal cancer patients, relationships between baseline variables and a detailed set of patient outcomes over a long time, and time-varying effects of a group of variables. The results presented advance our understanding of the long-term prognostic characteristics in colorectal cancer and are expected to inspire future studies and clinical care strategies.
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Affiliation(s)
- Yajun Yu
- Discipline of Genetics, Faculty of Medicine, Memorial University, 300 Prince Philip Drive, New Medical Education Building, St. John's, NL, A1B 3V6, Canada
| | - Megan Carey
- Discipline of Genetics, Faculty of Medicine, Memorial University, 300 Prince Philip Drive, New Medical Education Building, St. John's, NL, A1B 3V6, Canada
| | - William Pollett
- Discipline of Surgery, Faculty of Medicine, Memorial University, St. John's, NL, Canada
| | - Jane Green
- Discipline of Genetics, Faculty of Medicine, Memorial University, 300 Prince Philip Drive, New Medical Education Building, St. John's, NL, A1B 3V6, Canada
| | - Elizabeth Dicks
- Discipline of Medicine, Faculty of Medicine, Memorial University, St. John's, NL, Canada
| | - Patrick Parfrey
- Discipline of Medicine, Faculty of Medicine, Memorial University, St. John's, NL, Canada
| | - Yildiz E Yilmaz
- Discipline of Genetics, Faculty of Medicine, Memorial University, 300 Prince Philip Drive, New Medical Education Building, St. John's, NL, A1B 3V6, Canada.,Discipline of Medicine, Faculty of Medicine, Memorial University, St. John's, NL, Canada.,Department of Mathematics and Statistics, Faculty of Science, Memorial University, St. John's, NL, Canada
| | - Sevtap Savas
- Discipline of Genetics, Faculty of Medicine, Memorial University, 300 Prince Philip Drive, New Medical Education Building, St. John's, NL, A1B 3V6, Canada. .,Discipline of Oncology, Faculty of Medicine, Memorial University, St. John's, NL, Canada.
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12
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Rafter P, Purfield DC, Berry DP, Parnell AC, Gormley IC, Kearney JF, Coffey MP, Carthy TR. Characterization of copy number variants in a large multibreed population of beef and dairy cattle using high-density single nucleotide polymorphism genotype data. J Anim Sci 2018; 96:4112-4124. [PMID: 30239746 DOI: 10.1093/jas/sky302] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 08/07/2018] [Indexed: 02/07/2023] Open
Abstract
Copy number variants (CNVs) are a form of genomic variation that changes the structure of the genome through deletion or duplication of stretches of DNA. The objective of the present study was to characterize CNVs in a large multibreed population of beef and dairy bulls. The CNVs were called on the autosomes of 5,551 cattle from 22 different beef and dairy breeds, using 2 freely available software suites, QuantiSNP and PennCNV. All CNVs were classified into either deletions or duplications. The median concordance between PennCNV and QuantiSNP, per animal, was 18.5% for deletions and 0% for duplications. The low concordance rate between PennCNV and QuantiSNP indicated that neither algorithm, by itself, could identify all CNVs in the population. In total, PennCNV and QuantiSNP collectively identified 747,129 deletions and 432,523 duplications; 80.2% of all duplications and 69.1% of all deletions were present only once in the population. Only 0.154% of all CNVs identified were present in more than 50 animals in the population. The distribution of the percentage of the autosomes that were composed of deletions, per animal, was positively skewed, as was the distribution for the percentage of the autosomes that were composed of duplications, per animal. The first quartile, median, and third quartile of the distribution of the percentage of the autosomes that were composed of deletions were 0.019%, 0.037%, and 0.201%, respectively. The first quartile, median, and third quartile of the distribution of the percentage of the autosomes that were composed of duplications were 0.013%, 0.028%, and 0.076%, respectively. The distributions of the number of deletions and duplications per animal were both positively skewed. The interquartile range for the number of deletions per animal in the population was between 16 and 117, whereas for duplications it was between 8 and 23. Per animal, there tended to be twice as many deletions as duplications. The distribution of the length of deletions was positively skewed, as was the distribution of the length of duplications. The interquartile range for the length of deletions in the population was between 25 and 101 kb, and for duplications the interquartile range was between 46 and 235 kb. Per animal, duplications tended to be twice as long as deletions. This study provides a description of the characteristics and distribution of CNVs in a large multibreed population of beef and dairy cattle.
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Affiliation(s)
- Pierce Rafter
- Teagasc, Animal and Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland.,UCD School of Mathematics and Statistics, Insight Centre for Data Analytics, University College Dublin, Belfield, Dublin 4, Ireland
| | - Deirdre C Purfield
- Teagasc, Animal and Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland
| | - Donagh P Berry
- Teagasc, Animal and Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland
| | - Andrew C Parnell
- UCD School of Mathematics and Statistics, Insight Centre for Data Analytics, University College Dublin, Belfield, Dublin 4, Ireland
| | - I Claire Gormley
- UCD School of Mathematics and Statistics, Insight Centre for Data Analytics, University College Dublin, Belfield, Dublin 4, Ireland
| | | | - Mike P Coffey
- Animal and Veterinary Sciences, SRUC, Roslin Institute Building, Easter Bush, Midlothian EH25 9RG
| | - Tara R Carthy
- Teagasc, Animal and Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland
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13
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Hereditary Nonpolyposis Colorectal Cancer and Cancer Syndromes: Recent Basic and Clinical Discoveries. JOURNAL OF ONCOLOGY 2018; 2018:3979135. [PMID: 29849630 PMCID: PMC5937448 DOI: 10.1155/2018/3979135] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 03/12/2018] [Accepted: 03/20/2018] [Indexed: 12/14/2022]
Abstract
Approximately one-third of individuals diagnosed with colorectal cancer have a family history of cancer, suggesting that CRCs may result from a heritable component. Despite the availability of current gene-identification techniques, only 5% of all CRCs emerge from well-identifiable inherited causes for predisposition, including polyposis and nonpolyposis syndromes. Hereditary nonpolyposis colorectal cancer represents a large proportion of cases, and robustly affected patients are at increased risk for early onset, synchronous, and metachronous colorectal malignancies and extracolonic malignancies. HNPCC encompasses several cancer syndromes, such as Lynch syndrome, Lynch-like syndrome, and familial colorectal cancer type X, which have remarkable clinical presentations and overlapping genetic profiles that make clinical diagnosis a challenging task. Therefore, distinguishing between the HNPCC disorders is crucial for physicians as an approach to tailor different recommendations for patients and their at-risk family members according to the risks for colonic and extracolonic cancer associated with each syndrome. Identification of these potential patients through epidemiological characteristics and new genetic testing can estimate the individual risk, which informs appropriate cancer screening, surveillance, and/or treatment strategies. In the past three years, many appealing and important advances have been made in our understanding of the relationship between HNPCC and CRC-associated syndromes. The knowledge from the genetic profile of cancer syndromes and unique genotype-phenotype profiles in the different syndromes has changed our cognition. Therefore, this review presents and discusses HNPCC and several common nonpolyposis syndromes with respect to molecular phenotype, histopathologic features, and clinical presentation.
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14
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Werdyani S, Yu Y, Skardasi G, Xu J, Shestopaloff K, Xu W, Dicks E, Green J, Parfrey P, Yilmaz YE, Savas S. Germline INDELs and CNVs in a cohort of colorectal cancer patients: their characteristics, associations with relapse-free survival time, and potential time-varying effects on the risk of relapse. Cancer Med 2017; 6:1220-1232. [PMID: 28544645 PMCID: PMC5463068 DOI: 10.1002/cam4.1074] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 03/13/2017] [Accepted: 03/16/2017] [Indexed: 12/24/2022] Open
Abstract
INDELs and CNVs are structural variations that may play roles in cancer susceptibility and patient outcomes. Our objectives were a) to computationally detect and examine the genome‐wide INDEL/CNV profiles in a cohort of colorectal cancer patients, and b) to examine the associations of frequent INDELs/CNVs with relapse‐free survival time. We also identified unique variants in 13 Familial Colorectal Cancer Type X (FCCX) cases. The study cohort consisted of 495 colorectal cancer patients. QuantiSNP and PennCNV algorithms were utilized to predict the INDELs/CNVs using genome‐wide signal intensity data. Duplex PCR was used to validate predictions for 10 variants. Multivariable Cox regression models were used to test the associations of 106 common variants with relapse‐free survival time. Score test and the multivariable Cox proportional hazards models with time‐varying coefficients were applied to identify the variants with time‐varying effects on the relapse‐free survival time. A total of 3486 distinct INDELs/CNVs were identified in the patient cohort. The majority of these variants were rare (83%) and deletion variants (81%). The results of the computational predictions and duplex PCR results were highly concordant (93–100%). We identified four promising variants significantly associated with relapse‐free survival time (P < 0.05) in the multivariable Cox proportional hazards regression models after adjustment for clinical factors. More importantly, two additional variants were identified to have time‐varying effects on the risk of relapse. Finally, 58 rare variants were identified unique to the FCCX cases; none of them were detected in more than one patient. This is one of the first genome‐wide analyses that identified the germline INDEL/CNV profiles in colorectal cancer patients. Our analyses identified novel variants and genes that can biologically affect the risk of relapse in colorectal cancer patients. Additionally, for the first time, we identified germline variants that can potentially be early‐relapse markers in colorectal cancer.
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Affiliation(s)
- Salem Werdyani
- Discipline of Genetics, Faculty of Medicine, Memorial University, St. John's, Newfoundland and Labrador, Canada
| | - Yajun Yu
- Discipline of Genetics, Faculty of Medicine, Memorial University, St. John's, Newfoundland and Labrador, Canada
| | - Georgia Skardasi
- Discipline of Genetics, Faculty of Medicine, Memorial University, St. John's, Newfoundland and Labrador, Canada
| | - Jingxiong Xu
- Department of Biostatistics, Princess Margaret Hospital, University of Toronto, Toronto, Ontario, Canada
| | | | - Wei Xu
- Department of Biostatistics, Princess Margaret Hospital, University of Toronto, Toronto, Ontario, Canada.,Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
| | - Elizabeth Dicks
- Clinical Epidemiology Unit, Faculty of Medicine, Memorial University, St. John's, Newfoundland and Labrador, Canada
| | - Jane Green
- Discipline of Genetics, Faculty of Medicine, Memorial University, St. John's, Newfoundland and Labrador, Canada.,Discipline of Oncology, Faculty of Medicine, Memorial University, St. John's, Newfoundland and Labrador, Canada
| | - Patrick Parfrey
- Clinical Epidemiology Unit, Faculty of Medicine, Memorial University, St. John's, Newfoundland and Labrador, Canada
| | - Yildiz E Yilmaz
- Discipline of Genetics, Faculty of Medicine, Memorial University, St. John's, Newfoundland and Labrador, Canada.,Clinical Epidemiology Unit, Faculty of Medicine, Memorial University, St. John's, Newfoundland and Labrador, Canada.,Department of Mathematics and Statistics, Faculty of Science, Memorial University, St. John's, Newfoundland and Labrador, Canada
| | - Sevtap Savas
- Discipline of Genetics, Faculty of Medicine, Memorial University, St. John's, Newfoundland and Labrador, Canada.,Discipline of Oncology, Faculty of Medicine, Memorial University, St. John's, Newfoundland and Labrador, Canada
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