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Vogt M, Classen S, Krause AK, Peter NJ, Petersen C, Rothkamm K, Borgmann K, Meyer F. USP7 Deregulation Impairs S Phase Specific DNA Repair after Irradiation in Breast Cancer Cells. Biomedicines 2024; 12:762. [PMID: 38672118 PMCID: PMC11047985 DOI: 10.3390/biomedicines12040762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 03/13/2024] [Accepted: 03/19/2024] [Indexed: 04/28/2024] Open
Abstract
The ubiquitin specific protease 7 (USP7) is a deubiquitinating enzyme with numerous substrates. Aberrant expression of USP7 is associated with tumor progression. This study aims to investigate how a deregulated USP7 expression affects chromosomal instability and prognosis of breast cancer patients in silico and radiosensitivity and DNA repair in breast cancer cells in vitro. The investigations in silico were performed using overall survival and USP7 mRNA expression data of breast cancer patients. The results showed that a high USP7 expression was associated with increased chromosomal instability and decreased overall survival. The in vitro experiments were performed in a luminal and a triple-negative breast cancer cell line. Proliferation, DNA repair, DNA replication stress, and survival after USP7 overexpression or inhibition and irradiation were analyzed. Both, USP7 inhibition and overexpression resulted in decreased cellular survival, distinct radiosensitization and an increased number of residual DNA double-strand breaks in the S phase following irradiation. RAD51 recruitment and base incorporation were decreased after USP7 inhibition plus irradiation and more single-stranded DNA was detected. The results show that deregulation of USP7 activity disrupts DNA repair in the S phase by increasing DNA replication stress and presents USP7 as a promising target to overcome the radioresistance of breast tumors.
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Affiliation(s)
| | | | | | | | | | | | | | - Felix Meyer
- Department of Radiotherapy & Radiation Oncology, Hubertus Wald Tumor Center—University Cancer Center Hamburg, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (M.V.); (S.C.); (A.K.K.); (N.-J.P.); (C.P.); (K.R.); (K.B.)
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Wojtara MS, Kang J, Zaman M. Congenital Telangiectatic Erythema: Scoping Review. JMIR DERMATOLOGY 2023; 6:e48413. [PMID: 37796556 PMCID: PMC10587801 DOI: 10.2196/48413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 08/19/2023] [Accepted: 09/15/2023] [Indexed: 10/06/2023] Open
Abstract
BACKGROUND Congenital telangiectatic erythema (CTE), also known as Bloom syndrome, is a rare autosomal recessive disorder characterized by below-average height, a narrow face, a red skin rash occurring on sun-exposed areas of the body, and an increased risk of cancer. CTE is one of many genodermatoses and photodermatoses associated with defects in DNA repair. CTE is caused by a mutation occurring in the BLM gene, which causes abnormal breaks in chromosomes. OBJECTIVE We aimed to analyze the existing literature on CTE to provide additional insight into its heredity, the spectrum of clinical presentations, and the management of this disorder. In addition, the gaps in current research and the use of artificial intelligence to streamline clinical diagnosis and the management of CTE are outlined. METHODS A literature search was conducted on PubMed, DOAJ, and Scopus using search terms such as "congenital telangiectatic erythema," "bloom syndrome," and "bloom-torre-machacek." Due to limited current literature, studies published from January 2000 to January 2023 were considered for this review. A total of 49 sources from the literature were analyzed. RESULTS Through this scoping review, the researchers were able to identify several publications focusing on Bloom syndrome. Some common subject areas included the heredity of CTE, clinical presentations of CTE, and management of CTE. In addition, the literature on rare diseases shows the potential advancements in understanding and treatment with artificial intelligence. Future studies should address the causes of heterogeneity in presentation and examine potential therapeutic candidates for CTE and similarly presenting syndromes. CONCLUSIONS This review illuminated current advances in potential molecular targets or causative pathways in the development of CTE as well as clinical features including erythema, increased cancer risk, and growth abnormalities. Future studies should continue to explore innovations in this space, especially in regard to the use of artificial intelligence, including machine learning and deep learning, for the diagnosis and clinical management of rare diseases such as CTE.
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Affiliation(s)
- Magda Sara Wojtara
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Jayne Kang
- Department of Health Sciences, Queen's University, Kingston, ON, Canada
| | - Mohammed Zaman
- Department of Biology, Stony Brook University, Stony Brook, NY, United States
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Boussios S, Rassy E, Moschetta M, Ghose A, Adeleke S, Sanchez E, Sheriff M, Chargari C, Pavlidis N. BRCA Mutations in Ovarian and Prostate Cancer: Bench to Bedside. Cancers (Basel) 2022; 14:cancers14163888. [PMID: 36010882 PMCID: PMC9405840 DOI: 10.3390/cancers14163888] [Citation(s) in RCA: 56] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 08/09/2022] [Accepted: 08/10/2022] [Indexed: 11/17/2022] Open
Abstract
Simple Summary DNA damage is one of the hallmarks of cancer. Epithelial ovarian cancer (EOC) —especially the high-grade serous subtype—harbors a defect in at least one DNA damage response (DDR) pathway. Defective DDR results from a variety of lesions affecting homologous recombination (HR) and nonhomologous end joining (NHEJ) for double strand breaks, base excision repair (BER), and nucleotide excision repair (NER) for single strand breaks and mismatch repair (MMR). Apart from the EOC, mutations in the DDR genes, such as BRCA1 and BRCA2, are common in prostate cancer as well. Among them, BRCA2 lesions are found in 12% of metastatic castration-resistant prostate cancers, but very rarely in primary prostate cancer. Better understanding of the DDR pathways is essential in order to optimize the therapeutic choices, and has led to the design of biomarker-driven clinical trials. Poly(ADP-ribose) polymerase (PARP) inhibitors are now a standard therapy for EOC patients, and more recently have been approved for the metastatic castration-resistant prostate cancer with alterations in DDR genes. They are particularly effective in tumours with HR deficiency. Abstract DNA damage repair (DDR) defects are common in different cancer types, and these alterations can be exploited therapeutically. Epithelial ovarian cancer (EOC) is among the tumours with the highest percentage of hereditary cases. BRCA1 and BRCA2 predisposing pathogenic variants (PVs) were the first to be associated with EOC, whereas additional genes comprising the homologous recombination (HR) pathway have been discovered with DNA sequencing technologies. The incidence of DDR alterations among patients with metastatic prostate cancer is much higher compared to those with localized disease. Genetic testing is playing an increasingly important role in the treatment of patients with ovarian and prostate cancer. The development of poly (ADP-ribose) polymerase (PARP) inhibitors offers a therapeutic strategy for patients with EOC. One of the mechanisms of PARP inhibitors exploits the concept of synthetic lethality. Tumours with BRCA1 or BRCA2 mutations are highly sensitive to PARP inhibitors. Moreover, the synthetic lethal interaction may be exploited beyond germline BRCA mutations in the context of HR deficiency, and this is an area of ongoing research. PARP inhibitors are in advanced stages of development as a treatment for metastatic castration-resistant prostate cancer. However, there is a major concern regarding the need to identify reliable biomarkers predictive of treatment response. In this review, we explore the mechanisms of DDR, the potential for genomic analysis of ovarian and prostate cancer, and therapeutics of PARP inhibitors, along with predictive biomarkers.
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Affiliation(s)
- Stergios Boussios
- Department of Medical Oncology, Medway NHS Foundation Trust, Windmill Road, Gillingham ME7 5NY, UK
- Faculty of Life Sciences & Medicine, School of Cancer & Pharmaceutical Sciences, King’s College London, London SE1 9RT, UK
- AELIA Organization, 9th Km Thessaloniki-Thermi, 57001 Thessaloniki, Greece
- Correspondence:
| | - Elie Rassy
- Department of Medical Oncology, Gustave Roussy Institut, 94805 Villejuif, France
| | - Michele Moschetta
- Novartis Institutes for BioMedical Research, CH 4033 Basel, Switzerland
| | - Aruni Ghose
- Department of Medical Oncology, Medway NHS Foundation Trust, Windmill Road, Gillingham ME7 5NY, UK
- Department of Medical Oncology, Barts Cancer Centre, St. Bartholomew’s Hospital, Barts Health NHS Trust, London E1 1BB, UK
- Department of Medical Oncology, Mount Vernon Cancer Centre, East and North Hertfordshire NHS Trust, London KT1 2EE, UK
- Centre for Education, Faculty of Life Sciences and Medicine, King’s College London, London SE1 9RT, UK
| | - Sola Adeleke
- High Dimensional Neurology Group, UCL Queen’s Square Institute of Neurology, London WC1N 3BG, UK
- Department of Oncology, Guy’s and St Thomas’ Hospital, London SE1 9RT, UK
- School of Cancer & Pharmaceutical Sciences, King’s College London, Strand, London WC2R 2LS, UK
| | - Elisabet Sanchez
- Department of Medical Oncology, Medway NHS Foundation Trust, Windmill Road, Gillingham ME7 5NY, UK
| | - Matin Sheriff
- Department of Urology, Medway NHS Foundation Trust, Windmill Road, Gillingham ME7 5NY, UK
| | - Cyrus Chargari
- Department of Medical Oncology, Gustave Roussy Institut, 94805 Villejuif, France
| | - Nicholas Pavlidis
- Medical School, University of Ioannina, Stavros Niarchou Avenue, 45110 Ioannina, Greece
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Zhang Y, Fang M, Li S, Xu H, Ren J, Tu L, Zuo B, Yao W, Liang G. BTApep-TAT peptide inhibits ADP-ribosylation of BORIS to induce DNA damage in cancer. Mol Cancer 2022; 21:158. [PMID: 35918747 PMCID: PMC9344678 DOI: 10.1186/s12943-022-01621-w] [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: 05/19/2022] [Accepted: 07/11/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Brother of regulator of imprinted sites (BORIS) is expressed in most cancers and often associated with short survival and poor prognosis in patients. BORIS inhibits apoptosis and promotes proliferation of cancer cells. However, its mechanism of action has not been elucidated, and there is no known inhibitor of BORIS. METHODS A phage display library was used to find the BORIS inhibitory peptides and BTApep-TAT was identified. The RNA sequencing profile of BTApep-TAT-treated H1299 cells was compared with that of BORIS-knockdown cells. Antitumor activity of BTApep-TAT was evaluated in a non-small cell lung cancer (NSCLC) xenograft mouse model. BTApep-TAT was also used to investigate the post-translational modification (PTM) of BORIS and the role of BORIS in DNA damage repair. Site-directed mutants of BORIS were constructed and used for investigating PTM and the function of BORIS. RESULTS BTApep-TAT induced DNA damage in cancer cells and suppressed NSCLC xenograft tumor progression. Investigation of the mechanism of action of BTApep-TAT demonstrated that BORIS underwent ADP ribosylation upon double- or single-strand DNA damage. Substitution of five conserved glutamic acid (E) residues with alanine residues (A) between amino acids (AAs) 198 and 228 of BORIS reduced its ADP ribosylation. Inhibition of ADP ribosylation of BORIS by a site-specific mutation or by BTApep-TAT treatment blocked its interaction with Ku70 and impaired the function of BORIS in DNA damage repair. CONCLUSIONS The present study identified an inhibitor of BORIS, highlighted the importance of ADP ribosylation of BORIS, and revealed a novel function of BORIS in DNA damage repair. The present work provides a practical method for the future screening or optimization of drugs targeting BORIS.
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Affiliation(s)
- Yanmei Zhang
- School of Laboratory Medicine and Bioengineering, Hangzhou Medical College, Hangzhou, 310013, China.
| | - Mengdie Fang
- School of Laboratory Medicine and Bioengineering, Hangzhou Medical College, Hangzhou, 310013, China.,College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014, Zhejiang, China
| | - Shouye Li
- School of Laboratory Medicine and Bioengineering, Hangzhou Medical College, Hangzhou, 310013, China.,Zhejiang Eyoung Pharmaceutical Research and Development Center, Hangzhou, 311258, Zhejiang, China
| | - Hao Xu
- School of Laboratory Medicine and Bioengineering, Hangzhou Medical College, Hangzhou, 310013, China
| | - Juan Ren
- School of Laboratory Medicine and Bioengineering, Hangzhou Medical College, Hangzhou, 310013, China
| | - Linglan Tu
- School of Laboratory Medicine and Bioengineering, Hangzhou Medical College, Hangzhou, 310013, China
| | - Bowen Zuo
- School of Laboratory Medicine and Bioengineering, Hangzhou Medical College, Hangzhou, 310013, China
| | - Wanxin Yao
- School of Laboratory Medicine and Bioengineering, Hangzhou Medical College, Hangzhou, 310013, China
| | - Guang Liang
- School of Laboratory Medicine and Bioengineering, Hangzhou Medical College, Hangzhou, 310013, China. .,College of Pharmacy, Hangzhou Medical College, Hangzhou, 311300, Zhejiang, China.
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Guo S, Li T, Xu D, Xu J, Wang H, Li J, Bi X, Cao M, Xu Z, Xia Q, Cui Y, Li K. Prognostic Implications and Immune Infiltration Characteristics of Chromosomal Instability-Related Dysregulated CeRNA in Lung Adenocarcinoma. Front Mol Biosci 2022; 9:843640. [PMID: 35419410 PMCID: PMC8995899 DOI: 10.3389/fmolb.2022.843640] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Accepted: 02/22/2022] [Indexed: 12/14/2022] Open
Abstract
An accumulating body of research indicates that long-noncoding RNAs (lncRNAs) regulate the target genes and act as competitive endogenous RNAs (ceRNAs) playing an indispensable role in lung adenocarcinoma (LUAD). LUAD is frequently accompanied by the feature of chromosomal instability (CIN); however, CIN-related ceRNAs have not been investigated yet. We systematically analyzed and integrated CIN-related dysregulated ceRNAs characteristics in LUAD samples for the first time. In TCGA LUAD cohort, CIN in tumor samples was significantly higher than that in those of adjacent, and patients with high CIN risk tended to have worse clinical outcomes. We constructed a double-weighted CIN-related dysregulated ceRNA network, in which edge weight and node weight represented the disorder extent of ceRNA and the correlation of RNA expression level and prognosis, respectively. After module mining and analysis, a potential prognostic biomarker composed of 12 RNAs (8 mRNAs and 4 lncRNAs) named CIN-related dysregulated ceRNAs (CRDC) was obtained. The CRDC risk score had a positive relation with clinical stage and CIN, and patients with high CRDC risk scores exhibited poor prognosis. Moreover, CRDC tended to be an independent risk factor with high robustness to overcome the effect of multicollinearity among other explanatory variables for disease-specific survival (DSS) in TCGA and two GEO cohorts. The result of functional analysis indicated that CRDC was involved in multiple cancer progresses, especially immune-related pathways. The patients with lower CRDC risk had higher B cell, T cell CD4+, T cell CD8+, neutrophil, macrophage, and myeloid dendritic cell infiltration than the patients with higher CRDC risk. Meanwhile, patients with lower CRDC risk could get more benefits from immunological therapy. The results suggested that the CRDC could be a potential prognostic biomarker and an immunotherapy predictor for lung adenocarcinoma.
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Affiliation(s)
- Shengnan Guo
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, College of Biomedical Information and Engineering, Institute of Nephrology Second Affiliated Hospital and Hainan General Hospital, Hainan Medical University, Haikou, China
| | - Tianhao Li
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, College of Biomedical Information and Engineering, Institute of Nephrology Second Affiliated Hospital and Hainan General Hospital, Hainan Medical University, Haikou, China
| | - Dahua Xu
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, College of Biomedical Information and Engineering, Institute of Nephrology Second Affiliated Hospital and Hainan General Hospital, Hainan Medical University, Haikou, China
| | - Jiankai Xu
- College of Bioinformatics Science and Technology, Cancer Hospital, Harbin Medical University, Harbin, China
| | - Hong Wang
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, College of Biomedical Information and Engineering, Institute of Nephrology Second Affiliated Hospital and Hainan General Hospital, Hainan Medical University, Haikou, China
| | - Jian Li
- College of Bioinformatics Science and Technology, Cancer Hospital, Harbin Medical University, Harbin, China
| | - Xiaoman Bi
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, College of Biomedical Information and Engineering, Institute of Nephrology Second Affiliated Hospital and Hainan General Hospital, Hainan Medical University, Haikou, China
| | - Meng Cao
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, College of Biomedical Information and Engineering, Institute of Nephrology Second Affiliated Hospital and Hainan General Hospital, Hainan Medical University, Haikou, China
| | - Zhizhou Xu
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, College of Biomedical Information and Engineering, Institute of Nephrology Second Affiliated Hospital and Hainan General Hospital, Hainan Medical University, Haikou, China
| | - Qianfeng Xia
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, NHC Key Laboratory of Control of Tropical Diseases, School of Tropical Medicine, The Second Affiliated Hospital, Hainan Medical University, Haikou, China
- *Correspondence: Qianfeng Xia, ; Ying Cui, ; Kongning Li,
| | - Ying Cui
- College of Bioinformatics Science and Technology, Cancer Hospital, Harbin Medical University, Harbin, China
- *Correspondence: Qianfeng Xia, ; Ying Cui, ; Kongning Li,
| | - Kongning Li
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, College of Biomedical Information and Engineering, Institute of Nephrology Second Affiliated Hospital and Hainan General Hospital, Hainan Medical University, Haikou, China
- *Correspondence: Qianfeng Xia, ; Ying Cui, ; Kongning Li,
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Zhang W, Kong Y, Li Y, Shi F, Lyu J, Sheng C, Wang S, Wang Q. Novel Molecular Determinants of Response or Resistance to Immune Checkpoint Inhibitor Therapies in Melanoma. Front Immunol 2022; 12:798474. [PMID: 35087523 PMCID: PMC8787219 DOI: 10.3389/fimmu.2021.798474] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 12/16/2021] [Indexed: 12/13/2022] Open
Abstract
Background Immune checkpoint inhibitor (ICI) therapy dramatically prolongs melanoma survival. Currently, the identified ICI markers are sometimes ineffective. The objective of this study was to identify novel determinants of ICI efficacy. Methods We comprehensively curated pretreatment somatic mutational profiles and clinical information from 631 melanoma patients who received blockade therapy of immune checkpoints (i.e., CTLA-4, PD-1/PD-L1, or a combination). Significantly mutated genes (SMGs), mutational signatures, and potential molecular subtypes were determined. Their association with ICI responses was assessed simultaneously. Results We identified 27 SMGs, including four novel SMGs (COL3A1, NRAS, NARS2, and DCC) that are associated with ICI efficacy and well-known driver genes. COL3A1 mutations were associated with improved ICI overall survival (hazard ratio (HR): 0.64, 95% CI: 0.45-0.91, p = 0.012), whereas immune resistance was observed in patients with NRAS mutations (HR: 1.42, 95% CI: 1.10-1.82, p = 0.006). The presence of the tobacco smoking-related signature was significantly correlated with inferior prognoses (HR: 1.42, 95% CI: 1.11-1.82, p = 0.005). In addition, the signature resembling that of alkylating agents and a newly discovered signature both exhibited extended prognoses (both HR < 1, p < 0.05). Based on the activities of the extracted 6 mutational signatures, we identified one immune subtype that was significantly associated with better ICI outcomes (HR: 0.44, 95% CI: 0.23-0.87, p = 0.017). Conclusion We uncovered several novel SMGs and re-annotated mutational signatures that are linked to immunotherapy response or resistance. In addition, an immune subtype was found to exhibit favorable prognoses. Further studies are required to validate these findings.
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Affiliation(s)
- Wenjing Zhang
- Department of Health Statistics, Key Laboratory of Medicine and Health in Shandong Province, School of Public Health, Weifang Medical University, Weifang, China
| | - Yujia Kong
- Department of Health Statistics, Key Laboratory of Medicine and Health in Shandong Province, School of Public Health, Weifang Medical University, Weifang, China
| | - Yuting Li
- Tianjin Cancer Institute, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy of Tianjin, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Fuyan Shi
- Department of Health Statistics, Key Laboratory of Medicine and Health in Shandong Province, School of Public Health, Weifang Medical University, Weifang, China
| | - Juncheng Lyu
- Department of Health Statistics, Key Laboratory of Medicine and Health in Shandong Province, School of Public Health, Weifang Medical University, Weifang, China
| | - Chao Sheng
- Department of Epidemiology and Biostatistics, National Clinical Research Center for Cancer, Key Laboratory of Molecular Cancer Epidemiology of Tianjin, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Suzhen Wang
- Department of Health Statistics, Key Laboratory of Medicine and Health in Shandong Province, School of Public Health, Weifang Medical University, Weifang, China
| | - Qinghua Wang
- Department of Health Statistics, Key Laboratory of Medicine and Health in Shandong Province, School of Public Health, Weifang Medical University, Weifang, China
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Zhang W, Shi F, Kong Y, Li Y, Sheng C, Wang S, Wang Q. Association of PTPRT mutations with immune checkpoint inhibitors response and outcome in melanoma and non-small cell lung cancer. Cancer Med 2021; 11:676-691. [PMID: 34862763 PMCID: PMC8817076 DOI: 10.1002/cam4.4472] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 10/13/2021] [Accepted: 11/18/2021] [Indexed: 12/18/2022] Open
Abstract
Purpose Protein tyrosine phosphatase receptor type T (PTPRT), which is a well‐known phosphatase and mutates frequently in melanoma and non‐small cell lung cancer (NSCLC). Our research aims to elucidate its mutation association with immune checkpoint inhibitors (ICI) efficacy. Methods We integrated whole‐exome sequencing (WES)‐based somatic mutation profiles and clinical characteristics of 631 melanoma samples received ICI agents from eight studies and 109 NSCLC samples from two studies. For validation, 321 melanoma and 350 NSCLC immunotherapy samples with targeted next‐generation sequencing (NGS) were employed. Besides, an independent NSCLC cohort contained 240 samples was also collected for further corroboration. Distinct immune infiltration was evaluated according to the PTPRT mutational status. Results In the WES melanoma cohort, patients with PTPRT mutations harbored a significantly elevated ICI response rate (40.5% vs. 28.6%, p = 0.036) and a prolonged survival outcome (35.3 vs. 24.9 months, p = 0.006). In the WES NSCLC cohort, the favorable response and immunotherapy survival were also observed in PTPRT‐mutated patients (p = 0.036 and 0.019, respectively). For the validation cohorts, the associations of PTRPT mutations with better prognoses were identified in melanoma, NSCLC, and pan‐cancer patients with targeted‐NGS (all p < 0.05). Moreover, immunology analyses showed the higher mutation burden, increased lymphocyte infiltration, decreased‐ activated‐stroma, and immune response pathways were detected in patients with PTPRT mutations. Conclusion Our investigation indicates that PTPRT mutations may be considered as a potential indicator for assessing ICI efficacy in melanoma and NSCLC, even across multiple cancers. Further prospective validation cohorts are warranted.
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Affiliation(s)
- Wenjing Zhang
- Department of Health Statistics, Key Laboratory of Medicine and Health of Shandong Province, School of Public Health, Weifang Medical University, Weifang, China
| | - Fuyan Shi
- Department of Health Statistics, Key Laboratory of Medicine and Health of Shandong Province, School of Public Health, Weifang Medical University, Weifang, China
| | - Yujia Kong
- Department of Health Statistics, Key Laboratory of Medicine and Health of Shandong Province, School of Public Health, Weifang Medical University, Weifang, China
| | - Yuting Li
- Tianjin Cancer Institute, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy of Tianjin, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Chao Sheng
- Department of Epidemiology and Biostatistics, National Clinical Research Center for Cancer, Key Laboratory of Molecular Cancer Epidemiology of Tianjin, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Suzhen Wang
- Department of Health Statistics, Key Laboratory of Medicine and Health of Shandong Province, School of Public Health, Weifang Medical University, Weifang, China
| | - Qinghua Wang
- Department of Health Statistics, Key Laboratory of Medicine and Health of Shandong Province, School of Public Health, Weifang Medical University, Weifang, China
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Pan-Cancer Analysis Reveals FH as a Potential Prognostic and Immunological Biomarker in Lung Adenocarcinoma. DISEASE MARKERS 2021; 2021:8554844. [PMID: 34737838 PMCID: PMC8563123 DOI: 10.1155/2021/8554844] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 10/11/2021] [Indexed: 02/07/2023]
Abstract
Fumarate hydratase (FH) is an important enzymatic component in the tricarboxylic acid cycle. Studies have reported that FH plays an important role in hereditary leiomyomatosis and renal cell cancer (HLRCC). However, the role of FH in human different cancers remains unknown. This study is aimed at analyzing the prognostic value of FH and demonstrating the correlation between FH expression and tumor immunity. Results showed that FH was mutated or copy number varied in 27 types of cancer. FH mRNA was abnormally upregulated across various cancers. Survival analysis suggested high expression of FH was associated with poor prognosis in many cancer types, including lung adenocarcinoma (LUAD). Additionally, FH expression was associated with immune infiltration, including B cells, CD4+ T cells, CD8+ T cells, neutrophils, macrophages, and dendritic cells, especially in liver hepatocellular carcinoma (LIHC), LUAD, and lung squamous cell carcinoma (LUSC). Moreover, FH expression showed a strong correlation with immune checkpoint markers in LUAD and testicular germ cell tumors (TGCT). These results indicate that FH is an immunotherapeutic target and a potential prognostic biomarker in LUAD.
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Stewart NB, Rogers RL. Chromosomal rearrangements as a source of new gene formation in Drosophila yakuba. PLoS Genet 2019; 15:e1008314. [PMID: 31545792 PMCID: PMC6776367 DOI: 10.1371/journal.pgen.1008314] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 10/03/2019] [Accepted: 07/17/2019] [Indexed: 11/19/2022] Open
Abstract
The origins of new genes are among the most fundamental questions in evolutionary biology. Our understanding of the ways that new genetic material appears and how that genetic material shapes population variation remains incomplete. De novo genes and duplicate genes are a key source of new genetic material on which selection acts. To better understand the origins of these new gene sequences, we explored the ways that structural variation might alter expression patterns and form novel transcripts. We provide evidence that chromosomal rearrangements are a source of novel genetic variation that facilitates the formation of de novo exons in Drosophila. We identify 51 cases of de novo exon formation created by chromosomal rearrangements in 14 strains of D. yakuba. These new genes inherit transcription start signals and open reading frames when the 5' end of existing genes are combined with previously untranscribed regions. Such new genes would appear with novel peptide sequences, without the necessity for secondary transitions from non-coding RNA to protein. This mechanism of new peptide formations contrasts with canonical theory of de novo gene progression requiring non-coding intermediaries that must acquire new mutations prior to loss via pseudogenization. Hence, these mutations offer a means to de novo gene creation and protein sequence formation in a single mutational step, answering a long standing open question concerning new gene formation. We further identify gene expression changes to 134 existing genes, indicating that these mutations can alter gene regulation. Population variability for chromosomal rearrangements is considerable, with 2368 rearrangements observed across 14 inbred lines. More rearrangements were identified on the X chromosome than any of the autosomes, suggesting the X is more susceptible to chromosome alterations. Together, these results suggest that chromosomal rearrangements are a source of variation in populations that is likely to be important to explain genetic and therefore phenotypic diversity.
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Affiliation(s)
- Nicholas B. Stewart
- Department of Bioinformatics and Genomics, University of North Carolina at Charlotte, Charlotte, North Carolina, United States of America
- Department of Biological Sciences, Ft Hays State University, Ft Hays, Kansas, United States of America
| | - Rebekah L. Rogers
- Department of Bioinformatics and Genomics, University of North Carolina at Charlotte, Charlotte, North Carolina, United States of America
- * E-mail:
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Niu ZS, Niu XJ, Wang WH. Genetic alterations in hepatocellular carcinoma: An update. World J Gastroenterol 2016; 22:9069-9095. [PMID: 27895396 PMCID: PMC5107590 DOI: 10.3748/wjg.v22.i41.9069] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 09/20/2016] [Accepted: 10/19/2016] [Indexed: 02/06/2023] Open
Abstract
Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide. Although recent advances in therapeutic approaches for treating HCC have improved the prognoses of patients with HCC, this cancer is still associated with a poor survival rate mainly due to late diagnosis. Therefore, a diagnosis must be made sufficiently early to perform curative and effective treatments. There is a need for a deeper understanding of the molecular mechanisms underlying the initiation and progression of HCC because these mechanisms are critical for making early diagnoses and developing novel therapeutic strategies. Over the past decade, much progress has been made in elucidating the molecular mechanisms underlying hepatocarcinogenesis. In particular, recent advances in next-generation sequencing technologies have revealed numerous genetic alterations, including recurrently mutated genes and dysregulated signaling pathways in HCC. A better understanding of the genetic alterations in HCC could contribute to identifying potential driver mutations and discovering novel therapeutic targets in the future. In this article, we summarize the current advances in research on the genetic alterations, including genomic instability, single-nucleotide polymorphisms, somatic mutations and deregulated signaling pathways, implicated in the initiation and progression of HCC. We also attempt to elucidate some of the genetic mechanisms that contribute to making early diagnoses of and developing molecularly targeted therapies for HCC.
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MESH Headings
- Animals
- Biomarkers, Tumor/genetics
- Biomarkers, Tumor/metabolism
- Carcinoma, Hepatocellular/drug therapy
- Carcinoma, Hepatocellular/genetics
- Carcinoma, Hepatocellular/metabolism
- Carcinoma, Hepatocellular/pathology
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Neoplastic/metabolism
- Cell Transformation, Neoplastic/pathology
- Gene Expression Regulation, Neoplastic
- Genetic Predisposition to Disease
- Genomic Instability
- Humans
- Liver Neoplasms/drug therapy
- Liver Neoplasms/genetics
- Liver Neoplasms/metabolism
- Liver Neoplasms/pathology
- Molecular Diagnostic Techniques
- Molecular Targeted Therapy
- Mutation
- Patient Selection
- Phenotype
- Polymorphism, Single Nucleotide
- Precision Medicine
- Predictive Value of Tests
- Signal Transduction
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11
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Stoppa-Lyonnet D. The biological effects and clinical implications of BRCA mutations: where do we go from here? Eur J Hum Genet 2016; 24 Suppl 1:S3-9. [PMID: 27514841 PMCID: PMC5141575 DOI: 10.1038/ejhg.2016.93] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
BRCA1 and BRCA2 are tumour-suppressor genes encoding proteins that are essential for the repair of DNA double-strand breaks by homologous recombination (HR). Cells that lack either BRCA1 or BRCA2 repair these lesions by alternative, more error-prone mechanisms. Individuals carrying germline pathogenic mutations in BRCA1 or BRCA2 are at highly elevated risk of developing breast and/or ovarian cancer. Genetic testing for germline pathogenic mutations in BRCA1 and BRCA2 has proved to be a valuable tool for determining eligibility for cancer screening and prevention programmes. In view of increasing evidence that the HR DNA repair pathway can also be disrupted by sequence variants in other genes, screening for other BRCA-like defects has potential implications for patient care. Additionally, there is a growing argument for directly testing tumours for pathogenic mutations in BRCA1, BRCA2 and other genes involved in HR-DNA repair as inactivation of these genes may be strictly somatic. Tumours in which HR-DNA repair is altered are most likely to respond to emerging targeted therapies, such as inhibitors of poly-ADP ribose polymerase. This review highlights the biological role of pathogenic BRCA mutations and other associated defects in DNA damage repair mechanisms in breast and ovarian cancer, with particular focus on implications for patient management strategies.
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Affiliation(s)
- Dominique Stoppa-Lyonnet
- Department of Tumour Biology, Institut Curie, Paris, France
- INSERM U830, Institut Curie, Paris, France
- Department de Génétique, Université Paris Descartes, Service de Génétique, Institut Curie, Paris, France
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12
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Figura N, Marano L, Moretti E, Ponzetto A. Helicobacter pylori infection and gastric carcinoma: Not all the strains and patients are alike. World J Gastrointest Oncol 2016; 8:40-54. [PMID: 26798436 PMCID: PMC4714145 DOI: 10.4251/wjgo.v8.i1.40] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Revised: 10/06/2015] [Accepted: 11/03/2015] [Indexed: 02/05/2023] Open
Abstract
Gastric carcinoma (GC) develops in only 1%-3% of Helicobacter pylori (H. pylori) infected people. The role in GC formation of the bacterial genotypes, gene polymorphisms and host's factors may therefore be important. The risk of GC is enhanced when individuals are infected by strains expressing the oncoprotein CagA, in particular if CagA has a high number of repeats containing the EPIYA sequence in its C'-terminal variable region or particular amino acid sequences flank the EPIYA motifs. H. pylori infection triggers an inflammatory response characterised by an increased secretion of some chemokines by immunocytes and colonised gastric epithelial cells; these molecules are especially constituted by proteins composing the interleukin-1beta (IL-1β) group and tumour necrosis factor-alpha (TNF-α). Polymorphisms in the promoter regions of genes encoding these molecules, could account for high concentrations of IL-1β and TNF-α in the gastric mucosa, which may cause hypochlorhydria and eventually GC. Inconsistent results have been attained with other haplotypes of inflammatory and anti-inflammatory cytokines. Genomic mechanisms of GC development are mainly based on chromosomal or microsatellite instability (MSI) and deregulation of signalling transduction pathways. H. pylori infection may induce DNA instability and breaks of double-strand DNA in gastric mucocytes. Different H. pylori strains seem to differently increase the risk of cancer development run by the host. Certain H. pylori genotypes (such as the cagA positive) induce high degrees of chronic inflammation and determine an increase of mutagenesis rate, oxidative-stress, mismatch repair mechanisms, down-regulation of base excision and genetic instability, as well as generation of reactive oxygen species that modulate apoptosis; these phenomena may end to trigger or concur to GC development.
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13
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Pinheiro DDR, Ferreira WAS, Barros MBL, Araújo MD, Rodrigues-Antunes S, Borges BDN. Perspectives on new biomarkers in gastric cancer: Diagnostic and prognostic applications. World J Gastroenterol 2014; 20:11574-11585. [PMID: 25206265 PMCID: PMC4155351 DOI: 10.3748/wjg.v20.i33.11574] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 03/14/2014] [Accepted: 05/05/2014] [Indexed: 02/06/2023] Open
Abstract
Gastric cancer is considered one of the most deadly tumors worldwide. Even with the decline in its incidence, the mortality rate of this disease has remained high, mainly due to its late diagnosis and to the lack of precise prognostic markers. The main purpose of this review is to present genetic, epigenetic and proteomic molecular markers that may be used in a diagnostic and prognostic manner and to discuss the pros and cons of each type of marker for improving clinical practice. In this sense, we observed that the use of genetic markers, especially mutations and polymorphisms, should be carefully considered, as they are strongly affected by ethnicity. Proteomic-based markers show promise, but the higher costs of the associated techniques continue to make this approach expensive for routine use. Alternatively, epigenetic markers appear to be very promising, as they can be detected in bodily fluids as well as tissues. However, such markers must be used carefully because epigenetic changes may occur due to environmental factors and aging. Despite the advances in technology and its access, to date, there are few defined biomarkers of prognostic and diagnostic use for gastric tumors. Therefore, the use of a panel of several approaches (genetic, epigenetic and proteomic) should be considered the best alternative for clinical practice.
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14
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Abbotts R, Thompson N, Madhusudan S. DNA repair in cancer: emerging targets for personalized therapy. Cancer Manag Res 2014; 6:77-92. [PMID: 24600246 PMCID: PMC3933425 DOI: 10.2147/cmar.s50497] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Genomic deoxyribonucleic acid (DNA) is under constant threat from endogenous and exogenous DNA damaging agents. Mammalian cells have evolved highly conserved DNA repair machinery to process DNA damage and maintain genomic integrity. Impaired DNA repair is a major driver for carcinogenesis and could promote aggressive cancer biology. Interestingly, in established tumors, DNA repair activity is required to counteract oxidative DNA damage that is prevalent in the tumor microenvironment. Emerging clinical data provide compelling evidence that overexpression of DNA repair factors may have prognostic and predictive significance in patients. More recently, DNA repair inhibition has emerged as a promising target for anticancer therapy. Synthetic lethality exploits intergene relationships where the loss of function of either of two related genes is nonlethal, but loss of both causes cell death. Exploiting this approach by targeting DNA repair has emerged as a promising strategy for personalized cancer therapy. In the current review, we focus on recent advances with a particular focus on synthetic lethality targeting in cancer.
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Affiliation(s)
- Rachel Abbotts
- University of Nottingham, Academic Unit of Oncology, Division of Oncology, School of Medicine, Nottingham University Hospitals, City Hospital Campus, Nottingham, UK
| | - Nicola Thompson
- University of Nottingham, Academic Unit of Oncology, Division of Oncology, School of Medicine, Nottingham University Hospitals, City Hospital Campus, Nottingham, UK
| | - Srinivasan Madhusudan
- University of Nottingham, Academic Unit of Oncology, Division of Oncology, School of Medicine, Nottingham University Hospitals, City Hospital Campus, Nottingham, UK
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15
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Pan Y, Yang H, Claret FX. Emerging roles of Jab1/CSN5 in DNA damage response, DNA repair, and cancer. Cancer Biol Ther 2014; 15:256-62. [PMID: 24495954 DOI: 10.4161/cbt.27823] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Jab1/CSN5 is a multifunctional protein that plays an important role in integrin signaling, cell proliferation, apoptosis, and the regulation of genomic instability and DNA repair. Dysregulation of Jab1/CSN5 activity has been shown to contribute to oncogenesis by functionally inactivating several key negative regulatory proteins and tumor suppressors. In this review, we discuss our current understanding of the relationship between Jab1/CSN5 and DNA damage and summarize recent findings regarding opportunities for and challenges to therapeutic intervention.
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Affiliation(s)
- Yunbao Pan
- Department of Systems Biology; The University of Texas MD Anderson Cancer Center; Houston, TX USA; Department of Pathophysiology; Zhongshan School of Medicine; Sun Yat-Sen University; Guangzhou, Guangdong, PR China; Breast Tumor Center; Sun Yat-Sen Memorial Hospital; Sun Yat-Sen University; Guangzhou, Guangdong, PR China
| | - Huiling Yang
- Department of Pathophysiology; Zhongshan School of Medicine; Sun Yat-Sen University; Guangzhou, Guangdong, PR China
| | - Francois X Claret
- Department of Systems Biology; The University of Texas MD Anderson Cancer Center; Houston, TX USA; Experimental Therapeutic Academic Program and Cancer Biology Program; The University of Texas Graduate School of Biomedical Sciences at Houston; Houston, TX USA
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16
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Epstein RJ. The unpluggable in pursuit of the undruggable: tackling the dark matter of the cancer therapeutics universe. Front Oncol 2013; 3:304. [PMID: 24377088 PMCID: PMC3859984 DOI: 10.3389/fonc.2013.00304] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Accepted: 11/29/2013] [Indexed: 01/19/2023] Open
Abstract
The notion that targeted drugs can unplug gain-of-function tumor pathways has revitalized pharmaceutical research, but the survival benefits of this strategy have so far proven modest. A weakness of oncogene-blocking approaches is that they do not address the problem of cancer progression as selected by the recessive phenotypes of genetic instability and apoptotic resistance which in turn arise from loss-of-function – i.e., undruggable – defects of caretaker (e.g., BRCA, MLH1) or gatekeeper (e.g., TP53, PTEN) suppressor genes. Genetic instability ensures that rapid cell kill is balanced by rapid selection for apoptotic resistance and hence for metastasis, casting doubt on the assumption that cytotoxicity (“response”) remains the best way to identify survival-enhancing drugs. In the absence of gene therapy, it is proposed here that caretaker-defective (high-instability) tumors may be best treated with low-lethality drugs inducing replicative (RAS-RAF-ERK) arrest or dormancy, causing “stable disease” rather than tumorilytic remission. Gatekeeper-defective (death-resistant) tumors, on the other hand, may be best managed by combining survival (PI3K-AKT-mTOR) pathway blockade with metronomic or sequential pro-apoptotic drugs.
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Affiliation(s)
- Richard J Epstein
- Laboratory of Genome Evolution & Informatics, The Kinghorn Cancer Centre, and Clinical Informatics & Research Centre, Department of Oncology, St Vincent's Hospital, UNSW Clinical School , Sydney, NSW , Australia
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17
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Baumbusch LO, Helland Å, Wang Y, Liestøl K, Schaner ME, Holm R, Etemadmoghadam D, Alsop K, Brown P, Mitchell G, Fereday S, DeFazio A, Bowtell DDL, Kristensen GB, Lingjærde OC, Børresen-Dale AL. High levels of genomic aberrations in serous ovarian cancers are associated with better survival. PLoS One 2013; 8:e54356. [PMID: 23372714 PMCID: PMC3553118 DOI: 10.1371/journal.pone.0054356] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Accepted: 12/11/2012] [Indexed: 01/31/2023] Open
Abstract
Genomic instability and copy number alterations in cancer are generally associated with poor prognosis; however, recent studies have suggested that extreme levels of genomic aberrations may be beneficial for the survival outcome for patients with specific tumour types. We investigated the extent of genomic instability in predominantly high-grade serous ovarian cancers (SOC) using two independent datasets, generated in Norway (n = 74) and Australia (n = 70), respectively. Genomic instability was quantified by the Total Aberration Index (TAI), a measure of the abundance and genomic size of copy number changes in a tumour. In the Norwegian cohort, patients with TAI above the median revealed significantly prolonged overall survival (p<0.001) and progression-free survival (p<0.05). In the Australian cohort, patients with above median TAI showed prolonged overall survival (p<0.05) and moderately, but not significantly, prolonged progression-free survival. Results were confirmed by univariate and multivariate Cox regression analyses with TAI as a continuous variable. Our results provide further evidence supporting an association between high level of genomic instability and prolonged survival of high-grade SOC patients, possibly as disturbed genome integrity may lead to increased sensitivity to chemotherapeutic agents.
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Affiliation(s)
- Lars O Baumbusch
- Department of Genetics, Institute for Cancer Research, Oslo University Hospital, The Norwegian Radium Hospital, Oslo, Norway.
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18
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Zhang X, Li HM, Liu Z, Zhou G, Zhang Q, Zhang T, Zhang J, Zhang C. Loss of heterozygosity and methylation of multiple tumor suppressor genes on chromosome 3 in hepatocellular carcinoma. J Gastroenterol 2013; 48:132-43. [PMID: 22766745 DOI: 10.1007/s00535-012-0621-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2011] [Accepted: 05/21/2012] [Indexed: 02/04/2023]
Abstract
BACKGROUND Genetic and epigenetic alterations are the two key mechanisms in the development of hepatocellular carcinoma (HCC). However, how they contribute to hepatocarcinogenesis and the correlation between them has not been fully elucidated. METHODS A total of 48 paired HCCs and noncancerous tissues were used to detect loss of heterozygosity (LOH) and the methylation profiles of five tumor suppressor genes (RASSF1A, BLU, FHIT, CRBP1, and HLTF) on chromosome 3 by using polymerase chain reaction (PCR) and methylation-specific PCR. Gene expression was analyzed by immunohistochemistry and reverse transcription (RT)-PCR. RESULTS Sixteen of 48 (33.3 %) HCCs had LOH on at least one locus on chromosome 3, and two smallest common deleted regions (3p22.3-24.3 and 3p12.3-14.2) were identified. RASSF1A, BLU, and FHIT showed very high frequencies of methylation in HCCs (100, 81.3, and 64.6 %, respectively) and noncancerous tissues, but not in liver tissues from control patients. Well-differentiated HCCs showed high methylation frequencies of these genes but very low frequencies of LOH. Furthermore, BLU methylation was associated with an increased level of alpha-fetoprotein, and FHIT methylation was inversely correlated with HCC recurrence. In comparison, CRBP1 showed moderate frequencies of methylation, while HLTF showed low frequencies of methylation, and CRBP1 methylation occurred mainly in elderly patients. Treatment with 5-aza-2'-deoxycytidine demethylated at least one of these genes and restored their expression in a DNA methylation-dependent or -independent manner. CONCLUSIONS Hypermethylation of RASSF1A, BLU, and FHIT is a common and very early event in hepatocarcinogenesis; CRBP1 methylation may also be involved in the later stage. Although LOH was not too frequent on chromosome 3, it may play a role as another mechanism in hepatocarcinogenesis.
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Affiliation(s)
- Xiaoying Zhang
- Institute of Pathology and Pathophysiology, Shandong University School of Medicine, Jinan, 250012, China
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19
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Nam S, Long X, Kwon C, Kim S, Nephew KP. An integrative analysis of cellular contexts, miRNAs and mRNAs reveals network clusters associated with antiestrogen-resistant breast cancer cells. BMC Genomics 2012; 13:732. [PMID: 23270413 PMCID: PMC3560207 DOI: 10.1186/1471-2164-13-732] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2012] [Accepted: 12/20/2012] [Indexed: 12/28/2022] Open
Abstract
Background A major goal of the field of systems biology is to translate genome-wide profiling data (e.g., mRNAs, miRNAs) into interpretable functional networks. However, employing a systems biology approach to better understand the complexities underlying drug resistance phenotypes in cancer continues to represent a significant challenge to the field. Previously, we derived two drug-resistant breast cancer sublines (tamoxifen- and fulvestrant-resistant cell lines) from the MCF7 breast cancer cell line and performed genome-wide mRNA and microRNA profiling to identify differential molecular pathways underlying acquired resistance to these important antiestrogens. In the current study, to further define molecular characteristics of acquired antiestrogen resistance we constructed an “integrative network”. We combined joint miRNA-mRNA expression profiles, cancer contexts, miRNA-target mRNA relationships, and miRNA upstream regulators. In particular, to reduce the probability of false positive connections in the network, experimentally validated, rather than prediction-oriented, databases were utilized to obtain connectivity. Also, to improve biological interpretation, cancer contexts were incorporated into the network connectivity. Results Based on the integrative network, we extracted “substructures” (network clusters) representing the drug resistant states (tamoxifen- or fulvestrant-resistance cells) compared to drug sensitive state (parental MCF7 cells). We identified un-described network clusters that contribute to antiestrogen resistance consisting of miR-146a, -27a, -145, -21, -155, -15a, -125b, and let-7s, in addition to the previously described miR-221/222. Conclusions By integrating miRNA-related network, gene/miRNA expression and text-mining, the current study provides a computational-based systems biology approach for further investigating the molecular mechanism underlying antiestrogen resistance in breast cancer cells. In addition, new miRNA clusters that contribute to antiestrogen resistance were identified, and they warrant further investigation.
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Affiliation(s)
- Seungyoon Nam
- Cancer Genomics Branch, National Cancer Center, Goyang-si, Gyeonggi-do, 410-769, Korea.
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20
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Bianchetti L, Kieffer D, Féderkeil R, Poch O. Increased frequency of single base substitutions in a population of transcripts expressed in cancer cells. BMC Cancer 2012; 12:509. [PMID: 23137041 PMCID: PMC3522053 DOI: 10.1186/1471-2407-12-509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Accepted: 10/09/2012] [Indexed: 12/03/2022] Open
Abstract
Background Single Base Substitutions (SBS) that alter transcripts expressed in cancer originate from somatic mutations. However, recent studies report SBS in transcripts that are not supported by the genomic DNA of tumor cells. Methods We used sequence based whole genome expression profiling, namely Long-SAGE (L-SAGE) and Tag-seq (a combination of L-SAGE and deep sequencing), and computational methods to identify transcripts with greater SBS frequencies in cancer. Millions of tags produced by 40 healthy and 47 cancer L-SAGE experiments were compared to 1,959 Reference Tags (RT), i.e. tags matching the human genome exactly once. Similarly, tens of millions of tags produced by 7 healthy and 8 cancer Tag-seq experiments were compared to 8,572 RT. For each transcript, SBS frequencies in healthy and cancer cells were statistically tested for equality. Results In the L-SAGE and Tag-seq experiments, 372 and 4,289 transcripts respectively, showed greater SBS frequencies in cancer. Increased SBS frequencies could not be attributed to known Single Nucleotide Polymorphisms (SNP), catalogued somatic mutations or RNA-editing enzymes. Hypothesizing that Single Tags (ST), i.e. tags sequenced only once, were indicators of SBS, we observed that ST proportions were heterogeneously distributed across Embryonic Stem Cells (ESC), healthy differentiated and cancer cells. ESC had the lowest ST proportions, whereas cancer cells had the greatest. Finally, in a series of experiments carried out on a single patient at 1 healthy and 3 consecutive tumor stages, we could show that SBS frequencies increased during cancer progression. Conclusion If the mechanisms generating the base substitutions could be known, increased SBS frequency in transcripts would be a new useful biomarker of cancer. With the reduction of sequencing cost, sequence based whole genome expression profiling could be used to characterize increased SBS frequency in patient’s tumor and aid diagnostic.
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Affiliation(s)
- Laurent Bianchetti
- Plate-forme Bioinformatique de Strasbourg (BIPS), Institut de Génétique et de Biologie Moléculaire et Cellulaire (CNRS/INSERM/ULP), Illkirch, Cedex, France.
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21
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Fowler AK, Hewetson A, Agrawal RG, Dagda M, Dagda R, Moaddel R, Balbo S, Sanghvi M, Chen Y, Hogue RJ, Bergeson SE, Henderson GI, Kruman II. Alcohol-induced one-carbon metabolism impairment promotes dysfunction of DNA base excision repair in adult brain. J Biol Chem 2012; 287:43533-42. [PMID: 23118224 DOI: 10.1074/jbc.m112.401497] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The brain is one of the major targets of chronic alcohol abuse. Yet the fundamental mechanisms underlying alcohol-mediated brain damage remain unclear. The products of alcohol metabolism cause DNA damage, which in conditions of DNA repair dysfunction leads to genomic instability and neural death. We propose that one-carbon metabolism (OCM) impairment associated with long term chronic ethanol intake is a key factor in ethanol-induced neurotoxicity, because OCM provides cells with DNA precursors for DNA repair and methyl groups for DNA methylation, both critical for genomic stability. Using histological (immunohistochemistry and stereological counting) and biochemical assays, we show that 3-week chronic exposure of adult mice to 5% ethanol (Lieber-Decarli diet) results in increased DNA damage, reduced DNA repair, and neuronal death in the brain. These were concomitant with compromised OCM, as evidenced by elevated homocysteine, a marker of OCM dysfunction. We conclude that OCM dysfunction plays a causal role in alcohol-induced genomic instability in the brain because OCM status determines the alcohol effect on DNA damage/repair and genomic stability. Short ethanol exposure, which did not disturb OCM, also did not affect the response to DNA damage, whereas additional OCM disturbance induced by deficiency in a key OCM enzyme, methylenetetrahydrofolate reductase (MTHFR) in Mthfr(+/-) mice, exaggerated the ethanol effect on DNA repair. Thus, the impact of long term ethanol exposure on DNA repair and genomic stability in the brain results from OCM dysfunction, and MTHFR mutations such as Mthfr 677C→T, common in human population, may exaggerate the adverse effects of ethanol on the brain.
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Affiliation(s)
- Anna-Kate Fowler
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, Texas 79430, USA
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Abstract
The advent of massively parallel sequencing technologies has allowed the characterization of cancer genomes at an unprecedented resolution. Investigation of the mutational landscape of tumours is providing new insights into cancer genome evolution, laying bare the interplay of somatic mutation, adaptation of clones to their environment and natural selection. These studies have demonstrated the extent of the heterogeneity of cancer genomes, have allowed inferences to be made about the forces that act on nascent cancer clones as they evolve and have shown insight into the mutational processes that generate genetic variation. Here we review our emerging understanding of the dynamic evolution of the cancer genome and of the implications for basic cancer biology and the development of antitumour therapy.
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Affiliation(s)
- Lucy R Yates
- Cancer Genome Project, Wellcome Trust Sanger Institute, Hinxton CB10 1SA, UK
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23
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Hudler P. Genetic aspects of gastric cancer instability. ScientificWorldJournal 2012; 2012:761909. [PMID: 22606061 PMCID: PMC3353315 DOI: 10.1100/2012/761909] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Accepted: 11/30/2011] [Indexed: 12/13/2022] Open
Abstract
Unravelling the molecular mechanisms underlying gastric carcinogenesis is one of the major challenges in cancer genomics. Gastric cancer is a very complex and heterogeneous disease, and although much has been learned about the different genetic changes that eventually lead to its development, the detailed mechanisms still remain unclear. Malignant transformation of gastric cells is the consequence of a multistep process involving different genetic and epigenetic changes in numerous genes in combination with host genetic background and environmental factors. The majority of gastric adenocarcinomas are characterized by genetic instability, either microsatellite instability (MSI) or chromosomal instability (CIN). It is believed that chromosome destabilizations occur early in tumour progression. This review summarizes the most common genetic alterations leading to instability in sporadic gastric cancers and its consequences.
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Affiliation(s)
- Petra Hudler
- Medical Centre for Molecular Biology, Institute of Biochemistry, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, Ljubljana, Slovenia.
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Kim S, Roopra A, Alexander CM. A phenotypic mouse model of basaloid breast tumors. PLoS One 2012; 7:e30979. [PMID: 22347416 PMCID: PMC3276569 DOI: 10.1371/journal.pone.0030979] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Accepted: 12/30/2011] [Indexed: 12/23/2022] Open
Abstract
Chemotherapeutic strategies that target basal-like breast tumors are difficult to design without understanding their cellular and molecular basis. Here, we induce tumors in mice by carcinogen administration, creating a phenocopy of tumors with the diagnostic and functional aspects of human triple negative disease (including EGFR expression/lack of erbB, estrogen-independent growth and co-clustering of the transcriptome with other basaloid models). These tumor strains are a complement to established mouse models that are based on mutations in Brca1 and/or p53. Tumors comprise two distinct cell subpopulations, basal and luminal epithelial cells. These cell fractions were purified by flow cytometry, and only basal cell fractions found to have tumor initiating activity (cancer stem cells). The phenotype of serially regenerated tumors was stable, and irrespective of tumor precursor cell. Tumors were passaged entirely in vivo and serial generations tested for their phenotypic stability. The relative chemo-sensitivity of basal and luminal cells were evaluated. Upon treatment with anthracycline, tumors were effectively de-bulked, but recurred; this correlated with maintenance of a high rate of basal cell division throughout the treatment period. Thus, these tumors grow as robust cell mixtures of basal bipotential tumor initiating cells alongside a luminal majority, and the cellular response to drug administration is dominated by the distinct biology of the two cell types. Given the ability to separate basal and luminal cells, and the discovery potential of this approach, we propose that this mouse model could be a convenient one for preclinical studies.
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Affiliation(s)
- Soyoung Kim
- McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Avtar Roopra
- Department of Neuroscience, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Caroline M. Alexander
- McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- * E-mail:
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The DNA damage response: making it safe to play with knives. Mol Cell 2010; 40:179-204. [PMID: 20965415 DOI: 10.1016/j.molcel.2010.09.019] [Citation(s) in RCA: 3129] [Impact Index Per Article: 223.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Revised: 09/03/2010] [Accepted: 09/17/2010] [Indexed: 12/11/2022]
Abstract
Damage to our genetic material is an ongoing threat to both our ability to faithfully transmit genetic information to our offspring as well as our own survival. To respond to these threats, eukaryotes have evolved the DNA damage response (DDR). The DDR is a complex signal transduction pathway that has the ability to sense DNA damage and transduce this information to the cell to influence cellular responses to DNA damage. Cells possess an arsenal of enzymatic tools capable of remodeling and repairing DNA; however, their activities must be tightly regulated in a temporal, spatial, and DNA lesion-appropriate fashion to optimize repair and prevent unnecessary and potentially deleterious alterations in the structure of DNA during normal cellular processes. This review will focus on how the DDR controls DNA repair and the phenotypic consequences of defects in these critical regulatory functions in mammals.
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Nosho K, Baba Y, Tanaka N, Shima K, Hayashi M, Meyerhardt JA, Giovannucci E, Dranoff G, Fuchs CS, Ogino S. Tumour-infiltrating T-cell subsets, molecular changes in colorectal cancer, and prognosis: cohort study and literature review. J Pathol 2010; 222:350-66. [PMID: 20927778 PMCID: PMC3033700 DOI: 10.1002/path.2774] [Citation(s) in RCA: 380] [Impact Index Per Article: 27.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Accepted: 08/26/2010] [Indexed: 02/06/2023]
Abstract
The abundance of tumour-infiltrating T-cells has been associated with microsatellite instability (MSI) and a favourable prognosis in colorectal cancer. However, numerous molecular alterations have been associated with clinical outcome, and potentially confounding the biological and prognostic significance of tumour-infiltrating T-cells. We utilized a database of clinically and molecularly-annotated colon and rectal carcinoma cases (N = 768; stage I-IV) in two prospective cohort studies (the Nurses' Health Study and the Health Professionals Follow-up Study) and quantified the densities of CD3(+), CD8(+), CD45RO(+) (PTPRC), and FOXP3(+) cells within neoplastic epithelial areas using an Ariol image analysis system and tissue microarray. We used Cox proportional hazard models to compute the mortality hazard ratio, adjusting for clinical and molecular features including KRAS, BRAF, and PIK3CA mutations, MSI, CIMP, and LINE-1 hypomethylation. The densities of CD8(+), CD45RO(+), and FOXP3(+) cells were significantly associated with patient survival in univariate analyses (P(trend) < 0.007). In the multivariate model, tumour-infiltrating CD45RO(+)-cell density, but not CD3(+), CD8(+) or FOXP3(+)-cell density, was significantly associated with survival (p = 0.0032). In multivariate linear regression analysis, MSI-high (p < 0.0001) and high-level tumour LINE-1 methylation (p = 0.0013) were independently associated with higher CD45RO(+)-cell density. The survival benefit associated with CD45RO(+) cells was independent of MSI and LINE-1 status. In conclusion, tumour-infiltrating CD45RO(+)-cell density is a prognostic biomarker associated with longer survival of colorectal cancer patients, independent of clinical, pathological, and molecular features. In addition, MSI-high and tumour LINE-1 methylation level are independent predictors of CD45RO(+)-cell density. Our data offer a possible mechanism by which MSI confers an improved clinical outcome and support efforts to augment the host immune response in the tumour microenvironment as a strategy of targeted immunotherapy.
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Affiliation(s)
- Katsuhiko Nosho
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA
| | - Yoshifumi Baba
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA
| | - Noriko Tanaka
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA
- Department of Biostatistics, Harvard School of Public Health, Boston, MA
| | - Kaori Shima
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA
| | - Marika Hayashi
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA
| | - Jeffrey A. Meyerhardt
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA
| | - Edward Giovannucci
- Departments of Epidemiology and Nutrition, Harvard School of Public Health, Boston, MA
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA
| | - Glenn Dranoff
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA
- Cancer Vaccine Center, Dana-Farber Cancer Institute, Boston MA
| | - Charles S. Fuchs
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA
| | - Shuji Ogino
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA
- Department of Pathology, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA
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Human RECQ helicases: roles in DNA metabolism, mutagenesis and cancer biology. Semin Cancer Biol 2010; 20:329-39. [PMID: 20934517 DOI: 10.1016/j.semcancer.2010.10.002] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Accepted: 10/01/2010] [Indexed: 12/13/2022]
Abstract
Helicases use the energy of ATP hydrolysis to separate double-stranded nucleic acids to facilitate essential processes such as replication, recombination, transcription and repair. This article focuses on the human RECQ helicase gene and protein family. Loss of function of three different members has been shown to cause Bloom syndrome (BS), Werner syndrome (WS) and Rothmund-Thomson syndrome (RTS). This article outlines clinical and cellular features of these cancer predisposition syndromes, and discusses their pathogenesis in light of our understanding of RECQ helicase biochemical activities and in vivo functions. I also discuss the emerging role for RECQ helicases as predictors of disease risk and the response to therapy.
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Hall PA, Reis-Filho JS, Tomlinson IP, Poulsom R. An introduction to genes, genomes and disease. J Pathol 2010; 220:109-13. [PMID: 19960555 DOI: 10.1002/path.2652] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The human and other genome projects and subsequent resequencing programmes have provided new perspectives on the nature of the gene and how genes function. Understanding the complexity of the eukaryotic nucleus and the diversity of genetic regulatory mechanisms, including the role of non-coding RNAs, translational control mechanisms and the extraordinary prevalence of splicing, will be central to understanding how genes function, as will the recognition of gene dosage issues. This introduction to the 2010 Annual Review Issue, Genes, Genomes and Disease, provides overviews of these areas and then considers their relevance to a range of human diseases, including cardiovascular and renal disease, neural tube defects and cancer. The p53 gene is considered as an example of a massively regulated gene and the genetic perturbations in cancer are considered in a historical perspective. High-throughput genomic and transcriptomic methods have led to a paradigm shift in the way cancers are perceived and have changed the way translational research is performed. The progress in our understanding of chromosomal rearrangements in cancer, once believed to be incredibly rare events in epithelial malignancies, is discussed. The identification of low-penetrance cancer susceptibility genes through genome-wide association studies and their implications are reviewed. The contribution and limitations of expression profiling are discussed. In the last series of reviews, future challenges are addressed: the promise of synthetic lethality strategies in cancer therapy, a case for 'systems' approaches to genetic networks and the potential of single molecule genetic technologies. Finally, the question 'Does massively parallel DNA resequencing signify the end of histopathology as we know it?' is posed. Readers should find that the 2010 Annual Review Issue is an invaluable resource on contemporary genetics and its applications to understanding disease.
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Affiliation(s)
- Peter A Hall
- Institute of Pathology, School of Medicine, Dentistry and Biomedical Science, Queen's University of Belfast, Belfast BT12 6BL, UK.
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Bell DW. Our changing view of the genomic landscape of cancer. J Pathol 2010; 220:231-43. [PMID: 19918804 PMCID: PMC3195356 DOI: 10.1002/path.2645] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Accepted: 10/05/2009] [Indexed: 12/24/2022]
Abstract
Sporadic tumours, which account for the majority of all human cancers, arise from the acquisition of somatic, genetic and epigenetic alterations leading to changes in gene sequence, structure, copy number and expression. Within the last decade, the availability of a complete sequence-based map of the human genome, coupled with significant technological advances, has revolutionized the search for somatic alterations in tumour genomes. Recent landmark studies, which resequenced all coding exons within breast, colorectal, brain and pancreatic cancers, have shed new light on the genomic landscape of cancer. Within a given tumour type there are many infrequently mutated genes and a few frequently mutated genes, resulting in incredible genetic heterogeneity. However, when the altered genes are placed into biological processes and biochemical pathways, this complexity is significantly reduced and shared pathways that are affected in significant numbers of tumours can be discerned. The advent of next-generation sequencing technologies has opened up the potential to resequence entire tumour genomes to interrogate protein-encoding genes, non-coding RNA genes, non-genic regions and the mitochondrial genome. During the next decade it is anticipated that the most common forms of human cancer will be systematically surveyed to identify the underlying somatic changes in gene copy number, sequence and expression. The resulting catalogues of somatic alterations will point to candidate cancer genes requiring further validation to determine whether they have a causal role in tumourigenesis. The hope is that this knowledge will fuel improvements in cancer diagnosis, prognosis and therapy, based on the specific molecular alterations that drive individual tumours. In this review, I will provide a historical perspective on the identification of somatic alterations in the pre- and post-genomic eras, with a particular emphasis on recent pioneering studies that have provided unprecedented insights into the genomic landscape of human cancer.
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Affiliation(s)
- Daphne W Bell
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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