1
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Fukushi G, Yamada M, Kakugawa Y, Gotoh M, Tanabe N, Ushiama M, Watanabe T, Yamazaki T, Matsumoto M, Hirata M, Nakajima T, Sugano K, Yoshida T, Matsuda T, Igarashi Y, Saito Y. Genotype-phenotype correlation of small-intestinal polyps on small-bowel capsule endoscopy in familial adenomatous polyposis. Gastrointest Endosc 2023; 97:59-68.e7. [PMID: 36084716 DOI: 10.1016/j.gie.2022.08.042] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 08/18/2022] [Accepted: 08/30/2022] [Indexed: 01/20/2023]
Abstract
BACKGROUND AND AIMS In familial adenomatous polyposis (FAP), neoplastic lesions outside the colon have become increasingly important. The genotype-phenotype correlation has been established for duodenal polyps, and regular screening is recommended. However, this correlation remains unclear for small-intestinal lesions, except for reports on the relationship between their occurrence and Spigelman stage. Here, we used small-bowel capsule endoscopy (SBCE) to investigate the genotype-phenotype correlation of small-intestinal polyps in FAP. METHODS The genotype-phenotype correlation of small-intestinal polyps was investigated in patients with FAP who underwent SBCE, Esophagogastroduodenoscopy (EGD), and adenomatous polyposis coli (APC) gene analysis. Of 64 patients with FAP who underwent SBCE, 41 were included in the final analysis, 4 did not undergo a complete small intestine examination, and 19 did not undergo genetic analysis. RESULTS The prevalence (median number) of small-intestinal polyps by Spigelman stage was 26% (1.5), 0% (0), 44% (5), 60% (4), and 73% (25.5) for stages 0 to IV, respectively. Significantly more small-intestinal polyps were found in Spigelman stage III and IV groups than in the stage 0 group (P < .05). The APC variant was negative for 6 patients (15%), and the sites associated with more than 5 small-intestinal polyps were codons 278, 1062, 1114, 1281, 1307, 1314, and 1504. CONCLUSIONS In FAP patients, SBCE surveillance is potentially recommended for patients with pathogenic variants in the APC gene at codons 278 and 1062 to 1504 or with Spigelman stage III or higher.
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Affiliation(s)
- Gozo Fukushi
- Endoscopy Division, National Cancer Center Hospital, Tokyo, Japan; Cancer Screening Division, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan; Division of Gastroenterology and Hepatology, Toho University Omori Medical Center, Tokyo, Japan
| | - Masayoshi Yamada
- Endoscopy Division, National Cancer Center Hospital, Tokyo, Japan; Department of Genetic Medicine and Services, National Cancer Center Hospital, Tokyo, Japan
| | - Yasuo Kakugawa
- Cancer Screening Division, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan
| | - Masahiro Gotoh
- Department of Clinical Genomics, National Cancer Center Research Institute, Tokyo, Japan
| | - Noriko Tanabe
- Department of Genetic Medicine and Services, National Cancer Center Hospital, Tokyo, Japan
| | - Mineko Ushiama
- Department of Genetic Medicine and Services, National Cancer Center Hospital, Tokyo, Japan; Department of Clinical Genomics, National Cancer Center Research Institute, Tokyo, Japan
| | - Tomoko Watanabe
- Department of Genetic Medicine and Services, National Cancer Center Hospital, Tokyo, Japan
| | | | - Minori Matsumoto
- Cancer Screening Division, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan
| | - Makoto Hirata
- Department of Genetic Medicine and Services, National Cancer Center Hospital, Tokyo, Japan; Department of Clinical Genomics, National Cancer Center Research Institute, Tokyo, Japan
| | - Takeshi Nakajima
- Endoscopy Division, National Cancer Center Hospital, Tokyo, Japan
| | - Kokichi Sugano
- Department of Genetic Medicine, Koundo Hospital, Sasaki Foundation, Tokyo, Japan
| | - Teruhiko Yoshida
- Department of Genetic Medicine and Services, National Cancer Center Hospital, Tokyo, Japan; Department of Clinical Genomics, National Cancer Center Research Institute, Tokyo, Japan
| | - Takahisa Matsuda
- Endoscopy Division, National Cancer Center Hospital, Tokyo, Japan; Cancer Screening Division, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan; Division of Gastroenterology and Hepatology, Toho University Omori Medical Center, Tokyo, Japan
| | - Yoshinori Igarashi
- Division of Gastroenterology and Hepatology, Toho University Omori Medical Center, Tokyo, Japan
| | - Yutaka Saito
- Endoscopy Division, National Cancer Center Hospital, Tokyo, Japan
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2
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Kaissarian NM, Meyer D, Kimchi-Sarfaty C. Synonymous Variants: Necessary Nuance in our Understanding of Cancer Drivers and Treatment Outcomes. J Natl Cancer Inst 2022; 114:1072-1094. [PMID: 35477782 PMCID: PMC9360466 DOI: 10.1093/jnci/djac090] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 03/24/2022] [Accepted: 04/18/2022] [Indexed: 11/13/2022] Open
Abstract
Once called "silent mutations" and assumed to have no effect on protein structure and function, synonymous variants are now recognized to be drivers for some cancers. There have been significant advances in our understanding of the numerous mechanisms by which synonymous single nucleotide variants (sSNVs) can affect protein structure and function by affecting pre-mRNA splicing, mRNA expression, stability, folding, miRNA binding, translation kinetics, and co-translational folding. This review highlights the need for considering sSNVs in cancer biology to gain a better understanding of the genetic determinants of human cancers and to improve their diagnosis and treatment. We surveyed the literature for reports of sSNVs in cancer and found numerous studies on the consequences of sSNVs on gene function with supporting in vitro evidence. We also found reports of sSNVs that have statistically significant associations with specific cancer types but for which in vitro studies are lacking to support the reported associations. Additionally, we found reports of germline and somatic sSNVs that were observed in numerous clinical studies and for which in silico analysis predicts possible effects on gene function. We provide a review of these investigations and discuss necessary future studies to elucidate the mechanisms by which sSNVs disrupt protein function and are play a role in tumorigeneses, cancer progression, and treatment efficacy. As splicing dysregulation is one of the most well recognized mechanisms by which sSNVs impact protein function, we also include our own in silico analysis for predicting which sSNVs may disrupt pre-mRNA splicing.
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Affiliation(s)
- Nayiri M Kaissarian
- Hemostasis Branch, Division of Plasma Protein Therapeutics, Office of Tissues and Advanced Therapies, Center for Biologics Evaluation & Research, US Food and Drug Administration, Silver Spring, MD, USA
| | - Douglas Meyer
- Hemostasis Branch, Division of Plasma Protein Therapeutics, Office of Tissues and Advanced Therapies, Center for Biologics Evaluation & Research, US Food and Drug Administration, Silver Spring, MD, USA
| | - Chava Kimchi-Sarfaty
- Hemostasis Branch, Division of Plasma Protein Therapeutics, Office of Tissues and Advanced Therapies, Center for Biologics Evaluation & Research, US Food and Drug Administration, Silver Spring, MD, USA
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3
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Cho H, Yamada M, Sekine S, Tanabe N, Ushiama M, Hirata M, Ogawa G, Gotoh M, Yoshida T, Yoshikawa T, Saito Y, Kuchiba A, Oda I, Sugano K. Gastric cancer is highly prevalent in Lynch syndrome patients with atrophic gastritis. Gastric Cancer 2021; 24:283-291. [PMID: 32794040 DOI: 10.1007/s10120-020-01113-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 08/04/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND Although gastric cancer is one of the Lynch syndrome (LS)-related tumors, the clinicopathological features of gastric cancer in patients with LS remain uncertain. To investigate the incidence risk and clinicopathological features of gastric neoplasms in LS, we conducted a retrospective cohort study in Japanese LS patients. METHODS LS patients with pathogenic mismatch repair (MMR) gene variants were extracted from the LS registry of the National Cancer Center Hospital, Japan. Cumulative risks of gastric neoplasm, including dysplasia and cancer, were estimated using the Kaplan-Meier method. Gastric atrophy was evaluated endoscopically and/or histologically. Immunohistochemical staining for MMR proteins was performed for all available specimens. RESULTS Of 118 eligible patients, 26 patients were diagnosed with 58 gastric neoplasms. The cumulative incidence of gastric neoplasm was 41.0% (95% confidence interval, 26.9-55.0) at the age of 70. Of these, 13 (50%) patients developed synchronous and/or metachronous multiple gastric neoplasms. Among the 49 gastric neoplasms available for detailed pathological evaluation, all were associated with intestinal metaplasia. Immunohistochemically, 42 (86%) were MMR-deficient. The individuals with gastric atrophy had a significantly higher risk of developing gastric neoplasms compared with those without gastric atrophy (26 cases/54 individuals vs. 0 cases/53 individuals) (P = 0.026). CONCLUSION LS patients, particularly those with atrophic gastritis, are at high risk of gastric neoplasm and often develop multiple tumors. Endoscopic surveillance for gastric cancer is recommended for LS patients, especially those with atrophic gastritis.
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Affiliation(s)
- Hourin Cho
- Endoscopy Division, National Cancer Center Hospital, 5-1-1, Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Masayoshi Yamada
- Endoscopy Division, National Cancer Center Hospital, 5-1-1, Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan.
| | - Shigeki Sekine
- Division of Pathology and Clinical Laboratories, National Cancer Center Hospital, 5-1-1, Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Noriko Tanabe
- Department of Genetic Medicine and Services, National Cancer Center Hospital, 5-1-1, Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Mineko Ushiama
- Department of Genetic Medicine and Services, National Cancer Center Hospital, 5-1-1, Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Clinical Genomics, National Cancer Center Research Institute, 5-1-1, Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Makoto Hirata
- Department of Genetic Medicine and Services, National Cancer Center Hospital, 5-1-1, Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Gakuto Ogawa
- Biostatistics Division, Center for Research Administration and Support, National Cancer Center, 5-1-1, Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Masahiro Gotoh
- Department of Clinical Genomics, National Cancer Center Research Institute, 5-1-1, Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Teruhiko Yoshida
- Department of Genetic Medicine and Services, National Cancer Center Hospital, 5-1-1, Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Takaki Yoshikawa
- Department of Gastric Surgery, National Cancer Center Hospital, 5-1-1, Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Yutaka Saito
- Endoscopy Division, National Cancer Center Hospital, 5-1-1, Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Aya Kuchiba
- Biostatistics Division, Center for Research Administration and Support, National Cancer Center, 5-1-1, Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Ichiro Oda
- Endoscopy Division, National Cancer Center Hospital, 5-1-1, Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Kokichi Sugano
- Department of Genetic Medicine and Services, National Cancer Center Hospital, 5-1-1, Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Oncogene Research Unit/Cancer Prevention Unit, Tochigi Cancer Center Research Institute, 5-1-1, Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
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4
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Yamamoto G, Miyabe I, Tanaka K, Kakuta M, Watanabe M, Kawakami S, Ishida H, Akagi K. SVA retrotransposon insertion in exon of MMR genes results in aberrant RNA splicing and causes Lynch syndrome. Eur J Hum Genet 2020; 29:680-686. [PMID: 33293698 DOI: 10.1038/s41431-020-00779-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 10/30/2020] [Accepted: 11/17/2020] [Indexed: 11/10/2022] Open
Abstract
Lynch syndrome is an autosomal dominant hereditary cancer syndrome in which many cancers develop, the main one being colorectal cancer. Germline pathogenic variants in one of four mismatch repair (MMR) genes are known to be causative of this disease. Accurate diagnosis using genetic testing can greatly benefit the health of those affected. Recently, owing to the improvement of sequence techniques, complicated variants affecting the functions of MMR genes were discovered. In this study, we analyzed insertions of a retrotransposon-like sequence in exon 5 of the MSH6 gene and exon 3 of the MSH2 gene found in Japanese families suspected of having Lynch syndrome. Both of these insertions induced aberrant splicing, and these variants were successfully identified by mRNA sequencing or visual observation of mapping results, although a standard DNA-seq analysis pipeline failed to detect them. The insertion sequences were ~2.5 kbp in length and were found to have the structure of an SVA retrotransposon (SVA). One SVA sequence was not present in the hg19 or hg38 reference genome, but was in a Japanese-specific reference sequence (JRGv2). Our study illustrates the difficulties of identifying SVA insertions in disease genes, and that the possibility of polymorphic insertions should be considered when analyzing mobile elements.
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Affiliation(s)
- Gou Yamamoto
- Department of Molecular Diagnosis and Cancer Prevention, Saitama Cancer Center, 780 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan
| | - Izumi Miyabe
- Department of Molecular Diagnosis and Cancer Prevention, Saitama Cancer Center, 780 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan
| | - Keisuke Tanaka
- Department of Molecular Diagnosis and Cancer Prevention, Saitama Cancer Center, 780 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan
| | - Miho Kakuta
- Department of Molecular Diagnosis and Cancer Prevention, Saitama Cancer Center, 780 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan
| | - Motoko Watanabe
- Department of Clinical Genetics, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Satoru Kawakami
- Department of Urology, Saitama Medical Center, Saitama Medical University, Kawagoe, Saitama, Japan
| | - Hideyuki Ishida
- Department of Digestive Tract and General Surgery, Saitama Medical Center, Saitama Medical University, Kawagoe, Saitama, Japan
| | - Kiwamu Akagi
- Department of Molecular Diagnosis and Cancer Prevention, Saitama Cancer Center, 780 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan.
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5
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Morak M, Schaefer K, Steinke-Lange V, Koehler U, Keinath S, Massdorf T, Mauracher B, Rahner N, Bailey J, Kling C, Haeusser T, Laner A, Holinski-Feder E. Full-length transcript amplification and sequencing as universal method to test mRNA integrity and biallelic expression in mismatch repair genes. Eur J Hum Genet 2019; 27:1808-1820. [PMID: 31332305 DOI: 10.1038/s41431-019-0472-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 05/13/2019] [Accepted: 07/02/2019] [Indexed: 12/13/2022] Open
Abstract
In pathogenicity assessment, RNA-based analyses are important for the correct classification of variants, and require gene-specific cut-offs for allelic representation and alternative/aberrant splicing. Beside this, the diagnostic yield of RNA-based techniques capable to detect aberrant splicing or allelic loss due to intronic/regulatory variants has to be elaborated. We established a cDNA analysis for full-length transcripts (FLT) of the four DNA mismatch repair (MMR) genes to investigate the splicing pattern and transcript integrity with active/inhibited nonsense-mediated mRNA-decay (NMD). Validation was based on results from normal controls, samples with premature termination codons (PTC), samples with splice-site defects (SSD), and samples with pathogenic putative missense variants. The method was applied to patients with variants of uncertain significance (VUS) or unexplained immunohistochemical MMR deficiency. We categorized the allelic representation into biallelic (50 ± 10%) or allelic loss (≤10%), and >10% and <40% as unclear. We defined isoforms up to 10% and exon-specific exceptions as alternative splicing, set the cut-off for SSD in cDNA + P to 30-50%, and regard >10% and <30% as unclear. FLT cDNA analyses designated 16% of all putative missense variants and 12% of VUS as SSD, detected MMR-defects in 19% of the unsolved patients, and re-classified >30% of VUS. Our method allows a standardized, systematic cDNA analysis of the MMR FLTs to assess the pathogenicity mechanism of VUS on RNA level, which will gain relevance for precision medicine and gene therapy. Diagnostic accuracy will be enhanced by detecting MMR defects in hitherto unsolved patients. The data generated will help to calibrate a high-throughput NGS-based mRNA-analysis and optimize prediction programs.
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Affiliation(s)
- Monika Morak
- Medizinische Klinik und Poliklinik IV, Campus Innenstadt, Klinikum der Universität München, Ziemssenstr. 1, 80336, Munich, Germany. .,MGZ - Medical Genetics Center, Bayerstr. 3-5, 80335, Munich, Germany.
| | - Kerstin Schaefer
- Medizinische Klinik und Poliklinik IV, Campus Innenstadt, Klinikum der Universität München, Ziemssenstr. 1, 80336, Munich, Germany
| | - Verena Steinke-Lange
- Medizinische Klinik und Poliklinik IV, Campus Innenstadt, Klinikum der Universität München, Ziemssenstr. 1, 80336, Munich, Germany.,MGZ - Medical Genetics Center, Bayerstr. 3-5, 80335, Munich, Germany
| | - Udo Koehler
- MGZ - Medical Genetics Center, Bayerstr. 3-5, 80335, Munich, Germany
| | - Susanne Keinath
- Medizinische Klinik und Poliklinik IV, Campus Innenstadt, Klinikum der Universität München, Ziemssenstr. 1, 80336, Munich, Germany
| | - Trisari Massdorf
- Medizinische Klinik und Poliklinik IV, Campus Innenstadt, Klinikum der Universität München, Ziemssenstr. 1, 80336, Munich, Germany.,MGZ - Medical Genetics Center, Bayerstr. 3-5, 80335, Munich, Germany
| | - Brigitte Mauracher
- Medizinische Klinik und Poliklinik IV, Campus Innenstadt, Klinikum der Universität München, Ziemssenstr. 1, 80336, Munich, Germany
| | - Nils Rahner
- Medical Faculty, Institute of Human Genetics, Heinrich-Heine University, Düsseldorf, Germany
| | - Jessica Bailey
- Clinical Genetics, St. George's University Hospital NHS Foundation Trust, London, UK
| | | | - Tanja Haeusser
- MGZ - Medical Genetics Center, Bayerstr. 3-5, 80335, Munich, Germany
| | - Andreas Laner
- MGZ - Medical Genetics Center, Bayerstr. 3-5, 80335, Munich, Germany
| | - Elke Holinski-Feder
- Medizinische Klinik und Poliklinik IV, Campus Innenstadt, Klinikum der Universität München, Ziemssenstr. 1, 80336, Munich, Germany. .,MGZ - Medical Genetics Center, Bayerstr. 3-5, 80335, Munich, Germany.
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6
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Zhang X, Chen S, Yu J, Zhang Y, Lv M, Zhu M. Analysis of human MutS homolog 2 missense mutations in patients with colorectal cancer. Oncol Lett 2018; 15:6275-6282. [PMID: 29731845 PMCID: PMC5920917 DOI: 10.3892/ol.2018.8161] [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: 07/28/2017] [Accepted: 02/02/2018] [Indexed: 11/18/2022] Open
Abstract
Germline mutations of DNA mismatch repair gene human MutS homolog 2 (hMSH2) are associated with hereditary nonpolyposis colorectal cancer (HNPCC). A total of one-third of these mutations are missense mutations. Several hMSH2 missense mutations have been identified in patients in East Asia, although their function has not been evaluated. In the present study, the role of ten hMSH2 missense mutations in the pathogenesis of colorectal cancer was examined. The hMSH2/hMSH6 protein interaction system was established using yeast two-hybrid screening. Next, the missense mutations were analyzed for their ability to affect the protein interaction of hMSH2 with its partner hMSH6. Additionally, the Sorting Intolerant from Tolerant tool was applied to predict the effects of different amino acid substitutions. The results demonstrated that certain hMSH2 mutations (L173R and C199R) caused a significant functional change in the human hMutSα complex and were identified to be pathological mutations. The Y408C, D603Y, P696L and S703Y mutations partially affected interaction and partly affected the function of hMSH2. The remaining four variants, T8M, I169V, A370T and Q419K, may be non-functional polymorphisms or could affect protein function through other molecular mechanisms. The present study evaluated the functional consequences of previously unknown missense mutations in hMSH2, and may contribute to improved clinical diagnosis and mutation screening of HNPCC.
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Affiliation(s)
- Xiaomei Zhang
- Department of Molecular Biology, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, Nanjing Medical University Affiliated Cancer Hospital, Nanjing, Jiangsu 210009, P.R. China
| | - Senqing Chen
- Department of Molecular Biology, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, Nanjing Medical University Affiliated Cancer Hospital, Nanjing, Jiangsu 210009, P.R. China
| | - Jun Yu
- Department of Molecular Biology, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, Nanjing Medical University Affiliated Cancer Hospital, Nanjing, Jiangsu 210009, P.R. China
| | - Yuanying Zhang
- Department of Molecular Biology, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, Nanjing Medical University Affiliated Cancer Hospital, Nanjing, Jiangsu 210009, P.R. China
| | - Min Lv
- Department of Molecular Biology, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, Nanjing Medical University Affiliated Cancer Hospital, Nanjing, Jiangsu 210009, P.R. China
| | - Ming Zhu
- Department of Molecular Biology, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, Nanjing Medical University Affiliated Cancer Hospital, Nanjing, Jiangsu 210009, P.R. China
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7
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Sugano K, Nakajima T, Sekine S, Taniguchi H, Saito S, Takahashi M, Ushiama M, Sakamoto H, Yoshida T. Germline PMS2 mutation screened by mismatch repair protein immunohistochemistry of colorectal cancer in Japan. Cancer Sci 2017; 107:1677-1686. [PMID: 27589204 PMCID: PMC5132277 DOI: 10.1111/cas.13073] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 08/29/2016] [Accepted: 08/31/2016] [Indexed: 11/29/2022] Open
Abstract
Germline PMS2 gene mutations were detected by RT‐PCR/direct sequencing of total RNA extracted from puromycin‐treated peripheral blood lymphocytes (PBL) and multiplex ligation‐dependent probe amplification (MLPA) analyses of Japanese patients with colorectal cancer (CRC) fulfilling either the revised Bethesda Guidelines or being an age at disease onset of younger than 70 years, and screened by mismatch repair protein immunohistochemistry of formalin‐fixed paraffin embedded sections. Of the 501 subjects examined, 7 (1.40%) showed the downregulated expression of the PMS2 protein alone and were referred to the genetic counseling clinic. Germline PMS2 mutations were detected in 6 (85.7%), including 3 nonsense and 1 frameshift mutations by RT‐PCR/direct sequencing and 2 genomic deletions by MLPA. No mutations were identified in the other MMR genes (i.e. MSH2,MLH1 and MSH6). The prevalence of the downregulated expression of the PMS2 protein alone was 1.40% among the subjects examined and IHC results predicted the presence of PMS2 germline mutations. RT‐PCR from puromycin‐treated PBL and MLPA may be employed as the first screening step to detect PMS2 mutations without pseudogene interference, followed by the long‐range PCR/nested PCR validation using genomic DNA.
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Affiliation(s)
- Kokichi Sugano
- Department of Genetic Medicine and Services, National Cancer Center Hospital, Tokyo, Japan.,Oncogene Research Unit/Cancer Prevention Unit, Tochigi Cancer Center Research Institute, Utsunomiya, Japan
| | - Takeshi Nakajima
- Department of Genetic Medicine and Services, National Cancer Center Hospital, Tokyo, Japan.,Department of Endoscopy, National Cancer Center Hospital, Tokyo, Japan
| | - Shigeki Sekine
- Department of Genetic Medicine and Services, National Cancer Center Hospital, Tokyo, Japan.,Molecular Pathology Division, National Cancer Center Research Institute, Tokyo, Japan
| | - Hirokazu Taniguchi
- Division of Pathology and Clinical Laboratories, National Cancer Center Research Institute, Tokyo, Japan
| | - Shinya Saito
- Oncogene Research Unit/Cancer Prevention Unit, Tochigi Cancer Center Research Institute, Utsunomiya, Japan
| | - Masahiro Takahashi
- Oncogene Research Unit/Cancer Prevention Unit, Tochigi Cancer Center Research Institute, Utsunomiya, Japan
| | - Mineko Ushiama
- Department of Genetic Medicine and Services, National Cancer Center Hospital, Tokyo, Japan.,Division of Genetics, National Cancer Center Research Institute, Tokyo, Japan
| | - Hiromi Sakamoto
- Department of Genetic Medicine and Services, National Cancer Center Hospital, Tokyo, Japan.,Division of Genetics, National Cancer Center Research Institute, Tokyo, Japan
| | - Teruhiko Yoshida
- Department of Genetic Medicine and Services, National Cancer Center Hospital, Tokyo, Japan.,Division of Genetics, National Cancer Center Research Institute, Tokyo, Japan
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8
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Taki K, Sato Y, Nomura S, Ashihara Y, Kita M, Tajima I, Sugano K, Arai M. Mutation analysis of MUTYH in Japanese colorectal adenomatous polyposis patients. Fam Cancer 2016; 15:261-5. [PMID: 26684191 DOI: 10.1007/s10689-015-9857-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Germline MUTYH mutations were investigated in 14 Japanese colorectal polyposis patients without germ line adenomatous polyposis coli (APC) gene mutations. Three patients had a heterozygous IVS10-2A>G MUTYH mutation. The onset of MUTYH-associated polyposis (MAP) occurs later than that of familial adenomatous polyposis with germline APC mutation. Thus, we compared the carrier frequency of MUTYH IVS10-2A>G heterozygote in the APC mutation negative cases with that in 115 controls over 70 years of age who showed no apparent clinical manifestations of cancer and claimed that they had no history of cancer at the time of enrollment. The frequency of IVS10-2A>G heterozygote in APC germline mutation negative polyposis patients was significantly higher than control subject (p = 0.012, Chi square test). Although the sample size is still too small to conclude, the IVS10-2A>G MUTYH heterozygote might add to the risk of developing germline APC mutation negative polyposis.
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Affiliation(s)
- Keiko Taki
- Clinical Genetic Oncology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo, 135-8550, Japan
- Division of Bioresources, Chemical Resources Laboratory, Tokyo Institute of Technology, Yokohama, Japan
| | - Yuri Sato
- Clinical Genetic Oncology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo, 135-8550, Japan
| | - Sachio Nomura
- Clinical Genetic Oncology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo, 135-8550, Japan
- Department of Clinical Research, Cancer Institute Hospital of Japanese Foundation for Cancer Research, Tokyo, Japan
| | - Yuumi Ashihara
- Clinical Genetic Oncology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo, 135-8550, Japan
| | - Mizuho Kita
- Clinical Genetic Oncology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo, 135-8550, Japan
| | | | - Kokichi Sugano
- Oncogene Research Unit/Cancer Prevention Unit, Tochigi Cancer Center Research Institute, Tochigi, Japan
| | - Masami Arai
- Clinical Genetic Oncology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo, 135-8550, Japan.
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9
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Characterization of the STK11 splicing variant as a normal splicing isomer in a patient with Peutz-Jeghers syndrome harboring genomic deletion of the STK11 gene. Hum Genome Var 2016; 3:16002. [PMID: 27081568 PMCID: PMC4775769 DOI: 10.1038/hgv.2016.2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2015] [Revised: 12/06/2015] [Accepted: 12/08/2015] [Indexed: 12/19/2022] Open
Abstract
We report a STK11 splicing variant comprising a 131-bp insertion that is derived from intron 1, which has previously been reported to possess potent pathogenicity. The same variant was detected in a Peutz–Jeghers syndrome patient harboring a genomic deletion in the vicinity of exon 1 of the STK11 gene, which indicated that this variant was derived from the wild-type allele. We also found the same variant in other normal subjects. This variant corresponds to the predicted transcript variant of STK11 (XM_011528209), which is derived from the genomic sequence of Chr19 (NT_011295.12). Therefore, we concluded that the splicing variant was not pathogenic.
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Yamaguchi J, Sato Y, Kita M, Nomura S, Yamamoto N, Kato Y, Ishikawa Y, Arai M. A novel deletion in the splice donor site of MLH1 exon 6 in a Japanese colon cancer patient with Lynch syndrome. Jpn J Clin Oncol 2015; 45:993-7. [PMID: 26185136 DOI: 10.1093/jjco/hyv103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 06/13/2015] [Indexed: 01/30/2023] Open
Abstract
Lynch syndrome is an autosomal dominantly inherited disease that is characterized by a predisposition to cancers, mainly colorectal cancer. Germline mutations of DNA mismatch repair genes such as MLH1, MSH2, MSH6 and PMS2 have been described in patients with Lynch syndrome. Here, we report deletion of 2 bp in the splice donor site of the MLH1 exon 6 (c.545+4_545+5delCA) in a 48-year-old Japanese woman with Lynch syndrome. RT-PCR direct sequencing analysis revealed that this mutation led to an increase in the level of an MLH1 transcript in which exon 6 was skipped, and may cause a frameshift (p.E153FfsX8). Therefore, this mutation appears to be pathogenic and is responsible for Lynch syndrome. Additionally, analysis of the patient's tumor cells indicated microsatellite instability high phenotype and loss of the MLH1 and PMS2 proteins. To our knowledge, this is a germline splice site mutation of MLH1 that has not been reported previously.
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Affiliation(s)
- Junya Yamaguchi
- Clinical Genetic Oncology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo
| | - Yuri Sato
- Clinical Genetic Oncology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo
| | - Mizuho Kita
- Clinical Genetic Oncology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo
| | - Sachio Nomura
- Clinical Genetic Oncology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo Department of Clinical Research, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo
| | - Noriko Yamamoto
- Division of Pathology, Cancer Institute, Japanese Foundation for Cancer Research, Tokyo, Japan
| | - Yo Kato
- Division of Pathology, Cancer Institute, Japanese Foundation for Cancer Research, Tokyo, Japan
| | - Yuichi Ishikawa
- Division of Pathology, Cancer Institute, Japanese Foundation for Cancer Research, Tokyo, Japan
| | - Masami Arai
- Clinical Genetic Oncology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo
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Challenges in assessing pathogenicity based on frequency of variants in mismatch repair genes: an extreme case of a MSH2 variant and a meta-analysis. Gene 2014; 546:421-4. [PMID: 24933000 DOI: 10.1016/j.gene.2014.06.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 04/30/2014] [Accepted: 06/13/2014] [Indexed: 11/21/2022]
Abstract
The clinical interpretation of variants in mismatch repair (MMR) genes associated with Lynch syndrome can be confusing when the functional nature of the variant is not clearly defined. We report an extreme case where a polymorphism in the MSH2 gene which had a low minor allele frequency, was misclassified as a mutation based on low evidential methods in the database and previous publications. We expanded this experience to perform a systematic meta-analysis in order to investigate other variants that have potentially been misclassified. Our results suggested that the interpretation of pathogenicity should be more cautious and emphasized the need for solid validation through multiple analyses including functional analysis for variants in MMR genes.
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Zhang M, Xiang S, Joo HY, Wang L, Williams KA, Liu W, Hu C, Tong D, Haakenson J, Wang C, Zhang S, Pavlovicz RE, Jones A, Schmidt KH, Tang J, Dong H, Shan B, Fang B, Radhakrishnan R, Glazer PM, Matthias P, Koomen J, Seto E, Bepler G, Nicosia SV, Chen J, Li C, Gu L, Li GM, Bai W, Wang H, Zhang X. HDAC6 deacetylates and ubiquitinates MSH2 to maintain proper levels of MutSα. Mol Cell 2014; 55:31-46. [PMID: 24882211 DOI: 10.1016/j.molcel.2014.04.028] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 01/21/2014] [Accepted: 04/16/2014] [Indexed: 11/28/2022]
Abstract
MutS protein homolog 2 (MSH2) is a key DNA mismatch repair protein. It forms the MSH2-MSH6 (MutSα) and MSH2-MSH3 (MutSβ) heterodimers, which help to ensure genomic integrity. MutSα not only recognizes and repairs mismatched nucleotides but also recognizes DNA adducts induced by DNA-damaging agents, and triggers cell-cycle arrest and apoptosis. Loss or depletion of MutSα from cells leads to microsatellite instability (MSI) and resistance to DNA damage. Although the level of MutSα can be reduced by the ubiquitin-proteasome pathway, the detailed mechanisms of this regulation remain elusive. Here we report that histone deacetylase 6 (HDAC6) sequentially deacetylates and ubiquitinates MSH2, leading to MSH2 degradation. In addition, HDAC6 significantly reduces cellular sensitivity to DNA-damaging agents and decreases cellular DNA mismatch repair activities by downregulation of MSH2. Overall, these findings reveal a mechanism by which proper levels of MutSα are maintained.
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Affiliation(s)
- Mu Zhang
- Department of Pathology and Cell Biology, USF Morsani College of Medicine, 12901 Bruce B. Downs Boulevard, Tampa, FL 33612, USA
| | - Shengyan Xiang
- Department of Pathology and Cell Biology, USF Morsani College of Medicine, 12901 Bruce B. Downs Boulevard, Tampa, FL 33612, USA
| | - Heui-Yun Joo
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Kaul Human Genetics Building 402A, 720 South 20th Street, Birmingham, AL 35294, USA
| | - Lei Wang
- Department of Pathology and Cell Biology, USF Morsani College of Medicine, 12901 Bruce B. Downs Boulevard, Tampa, FL 33612, USA
| | - Kendra A Williams
- Department of Pathology and Cell Biology, USF Morsani College of Medicine, 12901 Bruce B. Downs Boulevard, Tampa, FL 33612, USA
| | - Wei Liu
- Department of Pathology and Cell Biology, USF Morsani College of Medicine, 12901 Bruce B. Downs Boulevard, Tampa, FL 33612, USA
| | - Chen Hu
- Department of Pathology and Cell Biology, USF Morsani College of Medicine, 12901 Bruce B. Downs Boulevard, Tampa, FL 33612, USA
| | - Dan Tong
- Graduate Center for Toxicology, Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Joshua Haakenson
- Department of Pathology and Cell Biology, USF Morsani College of Medicine, 12901 Bruce B. Downs Boulevard, Tampa, FL 33612, USA
| | - Chuangui Wang
- Key Laboratory of Medical Cell Biology, Institute for Translational Medicine, China Medical University, Shengyang 110000, China
| | - Shengping Zhang
- Key Laboratory of Medical Cell Biology, Institute for Translational Medicine, China Medical University, Shengyang 110000, China
| | - Ryan E Pavlovicz
- Biophysics Program, The Ohio State University, Columbus, OH 43210, USA
| | - Amanda Jones
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Kaul Human Genetics Building 402A, 720 South 20th Street, Birmingham, AL 35294, USA
| | - Kristina H Schmidt
- Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, FL 33620, USA; Cancer Biology and Evolution Program, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL 33612, USA
| | - Jinfu Tang
- Department of Pathology and Cell Biology, USF Morsani College of Medicine, 12901 Bruce B. Downs Boulevard, Tampa, FL 33612, USA
| | - Huiqin Dong
- Department of Pathology and Cell Biology, USF Morsani College of Medicine, 12901 Bruce B. Downs Boulevard, Tampa, FL 33612, USA
| | - Bin Shan
- Medical Sciences, Washington State University at Spokane, 412E Spokane Falls Boulevard, Spokane, WA 99201, USA
| | - Bin Fang
- Proteomics, SRB-3, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL 33612, USA
| | - Rangasudhagar Radhakrishnan
- Cancer Biology and Evolution Program, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL 33612, USA
| | - Peter M Glazer
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Patrick Matthias
- Friedrich Miescher Institute for Biomedical Research, Novartis Research Foundation, 4058 Basel, Switzerland
| | - John Koomen
- Proteomics, SRB-3, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL 33612, USA
| | - Edward Seto
- Cancer Biology and Evolution Program, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL 33612, USA
| | - Gerold Bepler
- Molecular Therapeutics Program, Karmanos Cancer Institute, 4100 John R, Detroit, MI 48201, USA
| | - Santo V Nicosia
- Department of Pathology and Cell Biology, USF Morsani College of Medicine, 12901 Bruce B. Downs Boulevard, Tampa, FL 33612, USA; Chemical Biology and Molecular Medicine Program, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL 33612, USA
| | - Jiandong Chen
- Cancer Biology and Evolution Program, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL 33612, USA
| | - Chenglong Li
- Biophysics Program, The Ohio State University, Columbus, OH 43210, USA; Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA
| | - Liya Gu
- Graduate Center for Toxicology, Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Guo-Min Li
- Graduate Center for Toxicology, Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Wenlong Bai
- Department of Pathology and Cell Biology, USF Morsani College of Medicine, 12901 Bruce B. Downs Boulevard, Tampa, FL 33612, USA; Cancer Biology and Evolution Program, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL 33612, USA
| | - Hengbin Wang
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Kaul Human Genetics Building 402A, 720 South 20th Street, Birmingham, AL 35294, USA
| | - Xiaohong Zhang
- Department of Pathology and Cell Biology, USF Morsani College of Medicine, 12901 Bruce B. Downs Boulevard, Tampa, FL 33612, USA; Cancer Biology and Evolution Program, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL 33612, USA.
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Wimmer K, Wernstedt A. PMS2 gene mutational analysis: direct cDNA sequencing to circumvent pseudogene interference. Methods Mol Biol 2014; 1167:289-302. [PMID: 24823786 DOI: 10.1007/978-1-4939-0835-6_20] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The presence of highly homologous pseudocopies can compromise the mutation analysis of a gene of interest. In particular, when using PCR-based strategies, pseudogene co-amplification has to be effectively prevented. This is often achieved by using primers designed to be parental gene specific according to the reference sequence and by applying stringent PCR conditions. However, there are cases in which this approach is of limited utility. For example, it has been shown that the PMS2 gene exchanges sequences with one of its pseudogenes, named PMS2CL. This results in functional PMS2 alleles containing pseudogene-derived sequences at their 3'-end and in nonfunctional PMS2CL pseudogene alleles that contain gene-derived sequences. Hence, the paralogues cannot be distinguished according to the reference sequence. This shortcoming can be effectively circumvented by using direct cDNA sequencing. This approach is based on the selective amplification of PMS2 transcripts in two overlapping 1.6-kb RT-PCR products. In addition to avoiding pseudogene co-amplification and allele dropout, this method has also the advantage that it allows to effectively identify deletions, splice mutations, and de novo retrotransposon insertions that escape the detection of most DNA-based mutation analysis protocols.
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Affiliation(s)
- Katharina Wimmer
- Division of Human Genetics, Medical University Innsbruck, Peter-Mayr-Strasse 1, Innsbruck, 6020, Austria,
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Masood N, Yasmin A, Kayani MA. Genetic Deletions of GSTM1 and GSTT1 in Head and Neck Cancer: Review of the Literature from 2000 to 2012. Asian Pac J Cancer Prev 2013; 14:3535-9. [DOI: 10.7314/apjcp.2013.14.6.3535] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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15
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Shiozawa M, Miyakura Y, Tahara M, Morishima K, Kumano H, Koinuma K, Horie H, Lefor AT, Sata N, Yasuda Y, Gonda K, Takenoshita S, Tamura A, Fukushima N, Sugano K. Partial duplication of MSH2 spanning exons 7 through 14 in Lynch syndrome. J Gastroenterol 2013; 48:770-6. [PMID: 23595612 DOI: 10.1007/s00535-013-0804-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Accepted: 03/22/2013] [Indexed: 02/04/2023]
Abstract
BACKGROUND Lynch syndrome, also referred to as hereditary nonpolyposis colorectal cancer, is the most common form of hereditary colorectal cancer, and is associated with a high incidence of multiple primary neoplasms in various organs. METHODS A 79-year-old woman (patient 1) diagnosed with ascending colon cancer had a history of previous carcinomas of the uterus, stomach, uroepithelial tract, and colon. One year later, she developed a brain tumor (glioblastoma). A 54-year-old female (patient 2) was diagnosed with endometrial cancer and sigmoid colon cancer. Both patients underwent genetic evaluations independently. RESULTS No mutations were found in an exon-by-exon analysis of genomic DNA by polymerase chain reaction (PCR) and reverse transcription (RT)-PCR. However, multiplex ligation-dependent probe amplification (MLPA) identified genomic duplication spanning from exon 7 to exon 14 of the MSH2 gene in both patients. Due to the presence of this characteristic gene duplication, their pedigrees were investigated further, and these showed that they are paternal half-sisters, consistent with paternal inheritance. CONCLUSION Large genomic duplication from intron 6 through intron 14 in MSH2 is a very rare cause of Lynch syndrome and is difficult to identify with conventional methods. MLPA may be an alternative approach for detecting large-scale genomic rearrangements.
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Affiliation(s)
- Mikio Shiozawa
- Department of Surgery, Jichi Medical University, Shimotsuke, Tochigi, Japan
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Hu F, Li D, Wang Y, Yao X, Zhang W, Liang J, Lin C, Ren J, Zhu L, Wu Z, Li S, Li Y, Zhao X, Cui B, Dong X, Tian S, Zhao Y. Novel DNA variants and mutation frequencies of hMLH1 and hMSH2 genes in colorectal cancer in the Northeast China population. PLoS One 2013; 8:e60233. [PMID: 23573243 PMCID: PMC3616036 DOI: 10.1371/journal.pone.0060233] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Accepted: 02/23/2013] [Indexed: 12/31/2022] Open
Abstract
Research on hMLH1 and hMSH2 mutations tend to focus on Lynch syndrome (LS) and LS-like colorectal cancer (CRC). No studies to date have assessed the role of hMLH1 and hMSH2 genes in mass sporadic CRC (without preselection by MSI or early age of onset). We aimed to identify novel hMLH1 and hMSH2 DNA variants, to determine the mutation frequencies and sites in both sporadic and LS CRC and their relationships with clinicopathological characteristics of CRC in Northeast of China. 452 sporadic and 21 LS CRC patients were screened for germline and somatic mutations in hMLH1 and hMSH2 genes with PCR–SSCP sequencing. We identified 11 hMLH1 and seven hMSH2 DNA variants in our study cohort. Six of them were novel: four in hMLH1 gene (IVS8-16 A>T, c.644 GAT>GTT, c.1529 CAG>CGG and c.1831 ATT>TTT) and two in hMSH2 gene (−39 C>T, insertion AACAACA at c.1127 and deletion AAG at c.1129). In sporadic CRC, germline and somatic mutation frequencies of hMLH1/hMSH2 gene were 15.59% and 17.54%, respectively (p = 0.52). Germline mutations present in hMLH1 and hMSH2 genes were 5.28% and 10.78%, respectively (p<0.01). Somatic mutations in hMLH1 and hMSH2 genes were 6.73% and 11.70%, respectively (p = 0.02). In LS CRC, both germline and somatic mutation frequencies of hMLH1/hMSH2 gene were 28.57%. The most prevalent germline mutation site in hMSH2 gene was c.1168 CTT>TTT (3.90%), a polymorphism. Somatic mutation frequency of hMLH1/hMSH2 gene was significantly different in proximal, distal colon and rectal cancer (p = 0.03). Our findings elucidate the mutation spectrum and frequency of hMLH1 and hMSH2 genes in sporadic and LS CRC, and their relationships with clinicopathological characteristics of CRC.
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Affiliation(s)
- Fulan Hu
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, People’s Republic of China
| | - Dandan Li
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, People’s Republic of China
| | - Yibaina Wang
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, People’s Republic of China
| | - Xiaoping Yao
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, People’s Republic of China
| | - Wencui Zhang
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, People’s Republic of China
| | - Jing Liang
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, People’s Republic of China
| | - Chunqing Lin
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, People’s Republic of China
| | - Jiaojiao Ren
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, People’s Republic of China
| | - Lin Zhu
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, People’s Republic of China
| | - Zhiwei Wu
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, People’s Republic of China
| | - Shuying Li
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, People’s Republic of China
| | - Ye Li
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, People’s Republic of China
| | - Xiaojuan Zhao
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, People’s Republic of China
| | - Binbin Cui
- Department of Colorectal Surgery, Cancer Hospital of Harbin Medical University, Harbin, People’s Republic of China
| | - Xinshu Dong
- Department of Surgery, The Fourth Affiliated Hospital, Harbin Medical University, Harbin, People’s Republic of China
| | - Suli Tian
- Department of Surgery, The Fourth Affiliated Hospital, Harbin Medical University, Harbin, People’s Republic of China
| | - Yashuang Zhao
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, People’s Republic of China
- * E-mail:
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Li D, Hu F, Wang F, Cui B, Dong X, Zhang W, Lin C, Li X, Wang D, Zhao Y. Prevalence of pathological germline mutations of hMLH1 and hMSH2 genes in colorectal cancer. PLoS One 2013; 8:e51240. [PMID: 23526924 PMCID: PMC3602519 DOI: 10.1371/journal.pone.0051240] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Accepted: 11/05/2012] [Indexed: 02/07/2023] Open
Abstract
The prevalence of pathological germline mutations in colorectal cancer has been widely studied, as germline mutations in the DNA mismatch repair genes hMLH1 and hMSH2 confer a high risk of colorectal cancer. However, because the sample size and population of previous studies are very different from each other, the conclusions still remain controversial. In this paper, Databases such as PubMed were applied to search for related papers. The data were imported into Comprehensive Meta-Analysis V2, which was used to estimate the weighted prevalence of hMLH1 and hMSH2 pathological mutations and compare the differences of prevalence among different family histories, ethnicities and related factors. This study collected and utilized data from 102 papers. In the Amsterdam-criteria positive group, the prevalence of pathological germline mutations of the hMLH1 and hMSH2 genes was 28.55% (95%CI 26.04%–31.19%) and 19.41% (95%CI 15.88%–23.51%), respectively, and the prevalence of germline mutations in hMLH1/hMSH2 was 15.44%/10.02%, 20.43%/13.26% and 15.43%/11.70% in Asian, American multiethnic and European/Australian populations, respectively. Substitution mutations accounted for the largest proportion of germline mutations (hMLH1: 52.34%, hMSH2: 43.25%). The total prevalence of mutations of hMLH1 and hMSH2 in Amsterdam-criteria positive, Amsterdam-criteria negative and sporadic colorectal cancers was around 45%, 25% and 15%, respectively, and there were no obvious differences in the prevalence of germline mutations among different ethnicities.
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Affiliation(s)
- Dandan Li
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
| | - Fulan Hu
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
| | - Fan Wang
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
| | - Binbin Cui
- Department of Abdominal Surgery, The Tumor Hospital of Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
| | - Xinshu Dong
- Department of Abdominal Surgery, The Tumor Hospital of Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
| | - Wencui Zhang
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
| | - Chunqing Lin
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
| | - Xia Li
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
| | - Da Wang
- Department of Science and Technology Administration, Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
| | - Yashuang Zhao
- Department of Epidemiology, Public Health College, Harbin Medical University, Harbin, Heilongjiang Province, P. R. China
- * E-mail:
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Zhu M, Chen HM, Wang YP. Missense mutations of MLH1 and MSH2 genes detected in patients with gastrointestinal cancer are associated with exonic splicing enhancers and silencers. Oncol Lett 2013; 5:1710-1718. [PMID: 23760103 PMCID: PMC3678577 DOI: 10.3892/ol.2013.1243] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Accepted: 02/18/2013] [Indexed: 01/11/2023] Open
Abstract
The MLH1 and MSH2 genes in DNA mismatch repair are important in the pathogenesis of gastrointestinal cancer. Recent studies of normal and alternative splicing suggest that the deleterious effects of missense mutations may in fact be splicing-related when they are located in exonic splicing enhancers (ESEs) or exonic splicing silencers (ESSs). In this study, we used ESE-finder and FAS-ESS software to analyze the potential ESE/ESS motifs of the 114 missense mutations detected in the two genes in East Asian gastrointestinal cancer patients. In addition, we used the SIFT tool to functionally analyze these mutations. The amount of the ESE losses (68) was 51.1% higher than the ESE gains (45) of all the mutations. However, the amount of the ESS gains (27) was 107.7% higher than the ESS losses (13). In total, 56 (49.1%) mutations possessed a potential exonic splicing regulator (ESR) error. Eighty-one mutations (71.1%) were predicted to be deleterious with a lower tolerance index as detected by the Sorting Intolerant from Tolerant (SIFT) tool. Among these, 38 (33.3%) mutations were predicted to be functionally deleterious and possess one potential ESR error, while 18 (15.8%) mutations were predicted to be functionally deleterious and exhibit two potential ESR errors. These may be more likely to affect exon splicing. Our results indicated that there is a strong correlation between missense mutations in MLH1 and MSH2 genes detected in East Asian gastrointestinal cancer patients and ESR motifs. In order to correctly understand the molecular nature of mutations, splicing patterns should be compared between wild-type and mutant samples.
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Affiliation(s)
- Ming Zhu
- Jiangsu Key Laboratory of Molecular Medicine, Nanjing University School of Medicine, Nanjing 210093; ; Department of Molecular Biology, Jiangsu Institute of Cancer Research, Nanjing 210009, P.R. China
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Martín-López JV, Barrios Y, Medina-Arana V, Andújar M, Lee S, Gu L, Li GM, Rüschoff J, Salido E, Fishel R. The hMSH2(M688R) Lynch syndrome mutation may function as a dominant negative. Carcinogenesis 2012; 33:1647-54. [PMID: 22739024 DOI: 10.1093/carcin/bgs199] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The hMSH2(M688R) mismatch repair (MMR) gene mutation has been found in five large families from Tenerife, Spain, suggesting it is a Lynch syndrome or hereditary non-polyposis colorectal cancer (LS/HNPCC) founder mutation. In addition to classical LS/HNPCC tumors, these families present with a high incidence of central nervous system (CNS) tumors normally associated with Turcot or constitutional mismatch repair deficiency (CMMR-D) syndromes. Turcot and CMMR-D mutations may be biallelic, knocking out both copies of the MMR gene. The hMSH2(M688R) mutation is located in the ATP hydrolysis (ATPase) domain. We show that the hMSH2(M688R)-hMSH6 heterodimer binds to mismatched nucleotides but lacks normal ATP functions and inhibits MMR in vitro when mixed with the wild-type (WT) heterodimer. Another alteration that has been associated with LS/HNPCC, hMSH2(M688I)-hMSH6, displays no identifiable differences with the WT heterodimer. Interestingly, some extracolonic tumors from hMSH2(M688R) carriers may express hMSH2-hMSH6, yet display microsatellite instability (MSI). The functional analysis along with variability in tumor expression and the high incidence of CNS tumors suggests that hMSH2(M688R) may act as a dominant negative in some tissues, while the hMSH2(M688I) is most likely a benign polymorphism.
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Affiliation(s)
- Juana V Martín-López
- Unidad de Investigación Mixta HUC-ULL, Facultad de Medicina, Universidad de La Laguna, La Laguna, Santa Cruz de Tenerife, 38002, Spain
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Banno K, Yanokura M, Kobayashi Y, Kawaguchi M, Nomura H, Hirasawa A, Susumu N, Aoki D. Endometrial cancer as a familial tumor: pathology and molecular carcinogenesis (review). Curr Genomics 2011; 10:127-32. [PMID: 19794885 PMCID: PMC2699824 DOI: 10.2174/138920209787847069] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2009] [Revised: 01/28/2009] [Accepted: 01/29/2009] [Indexed: 11/22/2022] Open
Abstract
Some cases of endometrial cancer are associated with a familial tumor and are referred to as hereditary nonpolyposis colorectal cancer (HNPCC or Lynch syndrome). Such tumors are thought to be induced by germline mutation of the DNA mismatch repair (MMR) gene, but many aspects of the pathology of familial endometrial cancer are unclear and no effective screening method has been established. However, the pathology of endometrial cancer with familial tumor has been progressively clarified in recent studies. At present, about 0.5% of all cases of endometrial cancers meet the clinical diagnostic criteria for HNPCC. A recent analysis of the three MMR genes (hMLH1, hMSH2 and hMSH6) revealed germline mutations in 18 of 120 cases (15.0%) of endometrial cancer with familial accumulation of cancer or double cancer, with a frameshift mutation of the hMSH6 gene being the most common. Many cases with mutation did not meet the current clinical diagnostic criteria for HNPCC, indicating that familial endometrial cancer is often not diagnosed as HNPCC. The results suggest that the hMSH6 gene mutation may be important in carcinogenesis in endometrial cancer and germline mutations of the MMR gene may be more prevalent in cases associated with familial accumulation of cancer. An international large-scale muticenter study is required to obtain further information about the pathology of endometrial cancer as a familial tumor.
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Affiliation(s)
- Kouji Banno
- Department of Obstetrics and Gynecology, Keio University School of Medicine, Tokyo, Japan
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21
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Wielders EAL, Dekker RJ, Holt I, Morris GE, te Riele H. Characterization of MSH2 variants by endogenous gene modification in mouse embryonic stem cells. Hum Mutat 2011; 32:389-96. [PMID: 21309037 DOI: 10.1002/humu.21448] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Accepted: 12/21/2010] [Indexed: 12/30/2022]
Abstract
Mutations in the mismatch repair gene MSH2 underlie hereditary nonpolyposis colorectal cancer (Lynch syndrome). Whereas disruptive mutations are overtly pathogenic, the implications of missense mutations found in sporadic colorectal cancer patients or in suspected Lynch syndrome families are often unknown. Adequate genetic counseling of mutation carriers requires phenotypic characterization of the variant allele. We present a novel approach to functionally characterize MSH2 missense mutations. Our approach involves introduction of the mutation into the endogenous gene of murine embryonic stem cells (ESC) by oligonucleotide-directed gene modification, a technique we recently developed in our lab. Subsequently, the mismatch repair capacity of mutant ESC is determined using a set of validated functional assays. We have evaluated four clinically relevant MSH2 variants and found one to completely lack mismatch repair capacity while three behaved as wild-type MSH2 and can therefore be considered as polymorphisms. Our approach contributes to an adequate risk assessment of mismatch repair missense mutations. We have also shown that oligonucleotide-directed gene modification provides a straightforward approach to recreate allelic variants in the endogenous gene in murine ESC. This approach can be extended to other hereditary conditions.
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Affiliation(s)
- Eva A L Wielders
- The Netherlands Cancer Institute, Division of Molecular Biology, Amsterdam, The Netherlands
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22
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Brieger A, Adam R, Passmann S, Plotz G, Zeuzem S, Trojan J. A CRM1-dependent nuclear export pathway is involved in the regulation of MutLα subcellular localization. Genes Chromosomes Cancer 2011; 50:59-70. [PMID: 21064154 DOI: 10.1002/gcc.20832] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023] Open
Abstract
MutLα plays an essential role in DNA mismatch repair (MMR) and is additionally involved in other cellular mechanisms such as the regulation of cell cycle checkpoints and apoptosis. Therefore, not only germline MMR gene defects but also the subcellular localization of MutLα might be of importance for the development of Lynch syndrome. Recently, we showed that MutLα contains functional nuclear import sequences and is most frequently localized in the nucleus. Here, we demonstrate that MutLα can move bidirectionally towards the nuclear membrane. Using MutLα transfected HEK293T cells we observed a significant shift of MLH1 and PMS2 from the nucleus to the cytoplasm after irradiation or cisplatin treatment. We analyzed both proteins for potential nuclear export sequences (NES) and identified one functional Rev-type NES (⁵⁷⁸LFDLAMLAL) in the C-terminal part of MLH1 that facilitates export via the CRM1/exportin pathway. Moreover, an MLH1-NES mutation detected in a patient with Lynch syndrome showed normal MMR activity but led to significantly impaired cytoplasmic transport after actinomycin D treatment. These results indicate that MutLα is able to shuttle from the nucleus to the cytoplasm, probably signaling DNA damages to downstream pathways. In conclusion, not only a defective MMR but also impaired nucleo-cytoplasmic shuttling might result in the onset of Lynch syndrome.
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Affiliation(s)
- Angela Brieger
- Medical Clinic I, Biomedical Research Laboratory, Goethe-University, Frankfurt a.M., Germany.
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23
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Hirai Y, Banno K, Suzuki M, Ichikawa Y, Udagawa Y, Sugano K, Miki Y. Molecular epidemiological and mutational analysis of DNA mismatch repair (MMR) genes in endometrial cancer patients with HNPCC-associated familial predisposition to cancer. Cancer Sci 2008; 99:1715-9. [PMID: 18624996 PMCID: PMC11159862 DOI: 10.1111/j.1349-7006.2008.00886.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2024] Open
Abstract
Recently, a high rate of endometrial cancer has been reported in women with hereditary non-polyposis colorectal cancer (HNPCC), suggesting a relationship between familial endometrial cancers and HNPCC. Familial endometrial cancers constitute only about 0.5% of all endometrial carcinomas and it is essential to examine family histories in detail. A mutational analysis of three DNA mismatch repair (MMR) genes (hMLH1, hMSH2 and hMSH6) in patients with endometrial cancer who meet our criteria for familial predisposition to HNPCC-associated endometrial cancers was performed. Mutations were detected in 18 of the 120 patients (15.0%). Most HNPCC-related endometrial cancers do not meet the New Amsterdam Criteria for HNPCC. These clinical criteria may identify only some HNPCC-associated endometrial cancers. Establishing the correct family history for endometrial cancer patients is important for diagnosing familial endometrial carcinomas. An analysis of MMR genes may be useful for patients with endometrial cancer showing familial aggregation. In addition, gynecologists must be accurately informed, and it is important to perform large-scale, multicenter studies both nationwide and internationally.
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Affiliation(s)
- Y Hirai
- Department of Cytology and Gynecology, Cancer Institute Hospital of Ariake, Japanese Foundation for Cancer Research, 3-10-6 Ariake, Koto-ku, Tokyo 135-8550, Japan
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24
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Etzler J, Peyrl A, Zatkova A, Schildhaus HU, Ficek A, Merkelbach-Bruse S, Kratz C, Attarbaschi A, Hainfellner J, Yao S, Messiaen L, Slavc I, Wimmer K. RNA-based mutation analysis identifies an unusual MSH6 splicing defect and circumvents PMS2 pseudogene interference. Hum Mutat 2008; 29:299-305. [DOI: 10.1002/humu.20657] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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25
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Yanaba K, Nakagawa H, Takeda Y, Koyama N, Sugano K. Muir-Torre syndrome caused by partial duplication of MSH2 gene by Alu-mediated nonhomologous recombination. Br J Dermatol 2007; 158:150-6. [PMID: 17941949 DOI: 10.1111/j.1365-2133.2007.08233.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
We describe a 54-year-old man with a pedicled tumour on the neck. The surgical specimen revealed a sebaceous carcinoma. He belonged to a cancer-prone family susceptible to gastrointestinal cancer. Systemic evaluation for latent malignancies revealed early-stage colonic adenocarcinoma. These findings were compatible with Muir-Torre syndrome (MTS). Microsatellite instability was detected in the sebaceous carcinoma, suggesting a DNA mismatch repair gene mutation. Moreover, duplication of exon 7 generated a nonsense codon at codon 427 of the MSH2 gene causing truncation of MSH2 protein. Immunohistochemical analysis showed diminished MSH2 protein levels in the sebaceous carcinoma and colonic adenocarcinoma. To date, there have been no reports showing duplication of exon 7 of the MSH2 gene in MTS or hereditary nonpolyposis colorectal cancer kindreds. Furthermore, the present case indicates that the dermatologist plays an important role in the diagnosis of MTS and evaluation for latent malignancies.
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Affiliation(s)
- K Yanaba
- Department of Dermatology, The Jikei University School of Medicine, 3-25-8 Nishishimbashi, Minato-ku, Tokyo, Japan.
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26
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Mei Q, Yan HL, Ding FX, Xue G, Huang JJ, Wang YZ, Sun SH. Single-nucleotide polymorphisms of mismatch repair genes in healthy Chinese individuals and sporadic colorectal cancer patients. ACTA ACUST UNITED AC 2006; 171:17-23. [PMID: 17074586 DOI: 10.1016/j.cancergencyto.2006.06.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2006] [Revised: 05/25/2006] [Accepted: 06/08/2006] [Indexed: 01/02/2023]
Abstract
Mismatch repair (MMR) genes are among of the most important genes associated with colorectal cancer (CRC). Single-nucleotide polymorphisms (SNPs) are generally thought to provide important information across a wide spectrum of life sciences; however, no study of association between SNPs of MMR genes and Chinese sporadic colorectal cancer (SCRC) is available. We chose 29 reported single-nucleotide variants that have rarely been verified in a population-based study. We identified SNPs and the genotype-phenotype association in Chinese populations of 150 healthy individuals and 160 SCRC patients. We extracted the genomic DNA from the blood of these individuals and used sequencing to determine these SNPs. Three SNPs (MLH1 394G-->C, 655A-->G, 1151T-->A) occurred with a frequency of 8.8-11.2% in the Chinese population. These SNPs formed a series with combined effects. The haplotype of concurrent MLH1 655 and 1151 SNPs and the haplotype combinations of MLH1 1151, MLH1 394 occurred exclusively in SCRC. None of the other 26 variants were detected in the Chinese population.
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Affiliation(s)
- Qian Mei
- Department of Medical Genetics, The Second Military Medical University, Xiangyin Road 800, Shanghai, China
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27
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Wang XL, Yuan Y, Zhang SZ, Cai SR, Huang YQ, Jiang Q, Zheng S. Clinical and genetic characteristics of Chinese hereditary nonpolyposis colorectal cancer families. World J Gastroenterol 2006; 12:4074-7. [PMID: 16810763 PMCID: PMC4087725 DOI: 10.3748/wjg.v12.i25.4074] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To analyze the clinical characteristics of Chinese hereditary nonpolyposis colorectal cancer (HNPCC) families and to screen the germline mutations of human mismatch repair genes hMLH1 and hMSH2 in the probands.
METHODS: Thirty-one independent Chinese HNPCC families were collected in Zhejiang Province. All of them met Chinese HNPCC criteria. Clinical data about patient gender, site of colorectal cancer, age of onset, history of multiple colorectal cancer, associated extracolonic cancer were recorded. PCR and denaturing high performance liquid chromatography (DHPLC) were employed to screen the mutations. Sequencing analysis was used to find out the exact mutation site and characteristics of the samples showing abnormal DHPLC profiles.
RESULTS: One hundred and thirty-six malignant neoplasms were found in 107 patients including 14 multiple cancers.One hundred and six of the 136 neoplasms (77.9%) were diagnosed as colorectal cancer, with an average age of onset at 48.57 ± 29.00 years. Gastric cancer was the most common extracolonic cancer (10.3%) in these families. Twenty-three different sequence variations in hMLHl and hMSH2 genes were detected in these 17 families. Fifteen sequence variations were located in the exons, including 5 SNPs, 3 silent mutations, 3 missense mutations, 2 nonsense mutations and 2 frameshift mutations. The latter seven mutations seemed to be pathogenic.
CONCLUSION: Germline mutations of hMLH1 and hMSH2 genes are identified in about one-third HNPCC kindreds fulfilling Chinese HNPCC criteria. Chinese HNPCC families have some particular clinical characteristics, such as a left-sided predominance, less synchronous or metachronous colorectal cancer, and frequent occurrence of gastric cancer.
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Affiliation(s)
- Xu-Lin Wang
- Cancer Institute, the 2nd Affiliated Hospital, College of Medicine, Zhejiang University, 88 Jie-Fang Road, Hangzhou 310009, Zhejiang Province, China
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28
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Chen X, Truong TTN, Weaver J, Bove BA, Cattie K, Armstrong BA, Daly MB, Godwin AK. Intronic alterations in BRCA1 and BRCA2: effect on mRNA splicing fidelity and expression. Hum Mutat 2006; 27:427-35. [PMID: 16619214 DOI: 10.1002/humu.20319] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Germline mutations in the human breast cancer susceptibility genes BRCA1 and BRCA2 account for the majority of hereditary breast and ovarian cancer. In spite of the large number of sequence variants identified in BRCA1 and BRCA2 mutation analyses, many of these genetic alterations are still classified as variants of unknown significance (VUS). In this study, we evaluated 12 BRCA1/2 intronic variants in order to differentiate their pathogenic or polymorphic effects on the mRNA splicing process. We detected the existence of aberrant splicing in three BRCA1 variants (c.301-2delA/IVS6-2delA, c.441+1G>A/IVS7+1G>A, and c.4986+6T>G/IVS16+6T>G) and two BRCA2 variants (c.8487+1G>A/IVS19+1G>A and c.8632-2A>G/IVS20-2A>G). All but one of the aberrant transcripts arise from mutations affecting the conserved splice acceptor or donor sequences and all would be predicted to result in expression of truncated BRCA1 or BRCA2 proteins. However, we demonstrated that four of these splice-site mutations (i.e., c.301-2delA, c.441+1G>A, c.4986+6T>G, and c.8632-2A>G) with premature termination codons were highly unstable and were unlikely to encode for abundant expression of a mutant protein. Three variants of BRCA1 (c.212+3A>G/IVS5+3A>G, c.593+8A>G/IVS9+8A>G, and c.4986-20A>G/IVS16-20A>G) and four variants of BRCA2 (c.516-19C>T/IVS6-19C>T, c.7976-4_7976_3delTT/IVS17-4delTT, c.8487+19A>G/IVS19+19A>G, and c.9256- 18C>A/IVS24- 18C>A) in our studies show no effects on the normal splicing process, and they are considered to be benign polymorphic alterations. Our studies help to clarify the aberrant splicing in BRCA1 and BRCA2 as well as provide information that can be used clinically to help counsel breast/ovarian cancer prone families.
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Affiliation(s)
- Xiaowei Chen
- Department of Medical Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111, USA
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29
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Huang D, Chen C, Sun W, Strom CM, Bender RA. High-throughput gene sequencing assay development for hereditary nonpolyposis colon cancer. Clin Colorectal Cancer 2005; 4:275-9. [PMID: 15555211 DOI: 10.3816/ccc.2004.n.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Hereditary nonpolyposis colorectal cancer (HNPCC) is the most common hereditary colon cancer syndrome and is responsible for as many as 10% of all colorectal cancers. Hereditary nonpolyposis colorectal cancer is autosomally dominant with a prevalence of 1 in 200-2000 and exhibits incomplete penetrance. Affected individuals have an approximately 70% lifetime risk of colon cancer with a mean age of onset of 44 years and an approximately 40% lifetime risk of endometrial cancer. At least 5 mismatch repair genes (MLH1, MSH2, MSH6, PMS1, PMS2) have been implicated in HNPCC; however, no predominant mutations were found in these genes. Mutation detection by direct sequencing has proven to be the most sensitive method. We have developed high-throughput full-length sequencing assays of the MLH1, MSH2, and MSH6 genes. These 3 genes account for approximately 90% of all germline mutations found in HNPCC. In our assays, 19 exons of MLH1, 16 exons of MSH2, 10 exons of MSH6, and the adjacent splice sites were amplified using polymerase chain reaction and loaded onto a capillary sequencing machine. Results were analyzed using sequence analysis software and stored in a relational database. Our assay method was validated using 15 affected patients and normal controls. It is anticipated that our high-throughput assay technique will provide accurate diagnoses for patients at risk for HNPCC and thereby facilitate early curative intervention.
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Affiliation(s)
- Donghui Huang
- Nichols Institute, Quest Diagnostics, Inc., San Juan Capistrano, CA 92690-6130, USA
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30
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Banno K, Susumu N, Nozawa S, Sugano K. Met688Ile and Leu390Phe of the MSH2 gene are not functional mutations, but polymorphisms in Japanese individuals. ACTA ACUST UNITED AC 2004; 155:92. [PMID: 15527911 DOI: 10.1016/j.cancergencyto.2004.03.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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31
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Murakami Y, Isogai K, Tomita H, Sakurai-Yageta M, Maruyama T, Hidaka A, Nose K, Sugano K, Kaneko A. Detection of allelic imbalance in the gene expression of hMSH2 or RB1 in lymphocytes from pedigrees of hereditary, nonpolyposis, colorectal cancer and retinoblastoma by an RNA difference plot. J Hum Genet 2004; 49:635-641. [PMID: 15480874 DOI: 10.1007/s10038-004-0201-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2004] [Accepted: 08/24/2004] [Indexed: 10/26/2022]
Abstract
A number of phenotypes in hereditary disorders or common diseases are associated with specific genotypes. However, little is known about the molecular basis of phenotypic variation among individuals carrying the same mutation or polymorphism. Here, a highly quantitative approach was taken to examine a relative amount of mRNA from two polymorphic alleles with a coefficient of variation of less than 10% using an RNA difference plot (RDP). RDP analysis revealed that most genes examined were expressed in equal amount from the two alleles in normal lymphocytes. In contrast, the relative amounts of hMSH2 or RB1 mRNAs carrying premature termination codons were significantly reduced compared with those of wild-type mRNAs in lymphocytes from carriers of hereditary, nonpolyposis, colorectal cancer and hereditary retinoblastoma. The balance of allelic expression of the RB1 was also significantly impaired in a pedigree of retinoblastoma carrying a missense mutation in codon 661. The relative expression of the mutant to the wild-type RB1 alleles among the carriers varied from 0.40 to 2.39. The analysis of the expression diversity of a disease-associated allele by RDP could provide a novel approach to elucidating the mechanisms underlying phenotypic variation among individuals carrying an identical mutation or polymorphism at a single locus.
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Affiliation(s)
- Yoshinori Murakami
- Tumor Suppression and the Functional Genomics Project, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan.
| | - Kana Isogai
- Tumor Suppression and the Functional Genomics Project, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
- Department of Microbiology, Showa University School of Pharmacy, Tokyo, Japan
| | - Hiroyuki Tomita
- Tumor Suppression and the Functional Genomics Project, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
- Bio-system Research Department, Central Research Laboratory, Hitachi Ltd, Tokyo, Japan
| | - Mika Sakurai-Yageta
- Tumor Suppression and the Functional Genomics Project, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Tomoko Maruyama
- Tumor Suppression and the Functional Genomics Project, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Akio Hidaka
- Clinical Laboratory, National Cancer Center Hospital, Tokyo, Japan
| | - Kiyoshi Nose
- Department of Microbiology, Showa University School of Pharmacy, Tokyo, Japan
| | - Kokichi Sugano
- Clinical Laboratory, National Cancer Center Hospital, Tokyo, Japan
- Oncogene Research Unit/Cancer Prevention Unit, Tochigi Cancer Center Research Institute, Utsunomiya, Japan
| | - Akihiro Kaneko
- Department of Ophthalmology, National Cancer Center Hospital, Tokyo, Japan
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Murakami Y, Okamura H, Sugano K, Yoshida T, Kazuma K, Akechi T, Uchitomi Y. Psychologic distress after disclosure of genetic test results regarding hereditary nonpolyposis colorectal carcinoma. Cancer 2004; 101:395-403. [PMID: 15241839 DOI: 10.1002/cncr.20363] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND To the authors' knowledge, there have been few studies of the psychologic distress after disclosure of genetic test results for hereditary nonpolyposis colorectal carcinoma (HNPCC). The objectives of this study were to identify the prevalence rates and predictors of psychologic distress and to evaluate the feelings of guilt after disclosure of the test results in Japanese probands and unaffected relatives. METHODS Probands and unaffected relatives were interviewed immediately after the first genetic counseling session for HNPCC and again 1 month after disclosure of the genetic test results. The prevalence of major and minor depression, acute stress disorder (ASD), posttraumatic stress disorder (PTSD), and posttraumatic stress symptoms (PTSS) were assessed using the Structured Clinical Interview based on the Diagnostic and Statistical Manual of Mental Disorders, 3rd edition revised (DSM-III-R) or the DSM-IV; feelings of guilt were investigated using a numeric scale and a semistructured interview. RESULTS Among 47 participants who completed the baseline interview, 42 participants (89%) completed the 1-month follow-up interview. Although none of the participants met the criteria for major depression, ASD, or PTSD at the follow-up interview, 3 of 42 participants (7%) met the criteria for minor depression and 2 participants (5%) had PTSS. The only predictor of psychologic distress found was the presence of a history of major or minor depression (odds ratio, 19.41; 95% confidence interval, 1.42-264.95; P < 0.05). Five of 42 participants (12%) had feelings of guilt. CONCLUSIONS Disclosure of genetic test results for HNPCC may not cause significant psychologic distress in Japanese probands or relatives. However, healthcare providers should not neglect to assess these individuals for psychologic responses, such as minor depression and PTSS.
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Affiliation(s)
- Yoshie Murakami
- Psycho-Oncology Division, National Cancer Center Research Institute East, Chiba, Japan
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33
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Miyakura Y, Sugano K, Akasu T, Yoshida T, Maekawa M, Saitoh S, Sasaki H, Nomizu T, Konishi F, Fujita S, Moriya Y, Nagai H. Extensive but hemiallelic methylation of the hMLH1 promoter region in early-onset sporadic colon cancers with microsatellite instability. Clin Gastroenterol Hepatol 2004; 2:147-56. [PMID: 15017620 DOI: 10.1016/s1542-3565(03)00314-8] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND AND AIMS Methylation of the hMLH1 promoter region is frequently observed in microsatellite instability (MSI)-positive sporadic colorectal carcinomas. We studied hMLH1 promoter methylation in peripheral blood lymphocytes of 87 index patients representing 29 cases of hereditary nonpolyposis colorectal cancers (HNPCCs), 28 cases of atypical HNPCCs, and 30 sporadic cases of the development of early-onset colorectal carcinomas or multiple primary cancers. METHODS Methylation of the hMLH1 promoter region was analyzed by Na-bisulfite polymerase chain reaction/single-strand conformation polymorphism analysis or methylation-specific polymerase chain reaction. MSI, allelic status of the hMLH1 locus, and loss of hMLH1 protein expression were examined in cases for which tumor tissues were available. RESULTS Extensive methylation of the hMLH1 promoter was detected in peripheral blood lymphocytes of 4 of 30 patients with sporadic early-onset colon cancer, among whom multiple primary cancers (1 colon and 1 endometrial cancer) developed in 2 cases. This methylation was not detected in analyses of HNPCC or atypical HNPCC groups or healthy control subjects. MSI was positive, and extensive methylation was detected in both cancers (colon and endometrial cancer) and normal tissues (colon, gastric mucosa, endometrium, and bone marrow) in all of the examined cases (3 of 3). Analysis of a polymorphic site in the hMLH1 promoter in 2 informative cases showed that methylation was hemiallelic. In 1 case, the unmethylated allele was lost in the colon cancer but not in the metachronous endometrial cancer. CONCLUSIONS Constitutive, hemiallelic methylation of the hMLH1 promoter region was shown to be associated with carcinogenesis in sporadic, early-onset MSI-positive colon cancers.
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Affiliation(s)
- Yasuyuki Miyakura
- Oncogene Research Unit/Cancer Prevention Unit, Tochigi Cancer Center Research Institute, Tochigi, Japan
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34
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Banno K, Susumu N, Hirao T, Yanokura M, Hirasawa A, Aoki D, Udagawa Y, Sugano K, Nozawa S. Identification of germline MSH2 gene mutations in endometrial cancer not fulfilling the new clinical criteria for hereditary nonpolyposis colorectal cancer. ACTA ACUST UNITED AC 2003; 146:58-65. [PMID: 14499697 DOI: 10.1016/s0165-4608(03)00157-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Endometrial cancer is the second most common malignancy in patients with hereditary nonpolyposis colorectal cancer (HNPCC). This cancer is caused by germline mutations in one of the DNA mismatch repair (MMR) genes. The present study was undertaken to analyze the relation between microsatellite instability (MSI) and germline mutations of MMR genes. We analyzed MSI in 38 cases of endometrial cancer. MSI was present in one or more (out of 5 examined) regions in 11 (29%) cases. Furthermore, alterations in MLH1 and MSH2, two culprit genes representative of HNPCC, were examined in the 11 MSI-positive patients using polymerase chain reaction-single-strand conformation polymorphism and sequencing. Germline mutations, namely, 1) a missense mutation at codon 688 (ATG-->ATA, Met-->Ile) and 2) a missense mutation at codon 390 (CTT-->TTT, Leu-->Phe) of the MSH2 gene, were found in 2 of the 11 patients (18%). Although these two cases do not fulfill the new Amsterdam criteria, they had strong family histories of colorectal and endometrial carcinoma. Our results show that genetic testing is important in cases of endometrial cancer with a history suggestive of HNPCC even if the new Amsterdam criteria are not fulfilled.
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Affiliation(s)
- Kouji Banno
- Department of Obstetrics and Gynecology, Keio University School of Medicine, Tokyo, Japan.
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35
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Renkonen E, Zhang Y, Lohi H, Salovaara R, Abdel-Rahman WM, Nilbert M, Aittomaki K, Jarvinen HJ, Mecklin JP, Lindblom A, Peltomaki P. Altered expression of MLH1, MSH2, and MSH6 in predisposition to hereditary nonpolyposis colorectal cancer. J Clin Oncol 2003; 21:3629-37. [PMID: 14512394 DOI: 10.1200/jco.2003.03.181] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
PURPOSE A considerable fraction (30% to 70%) of families with verified or putative hereditary nonpolyposis colorectal cancer fails to show mutations in DNA mismatch repair (MMR) genes. Our purpose was to address the genetic etiology of such families. MATERIALS AND METHODS We scrutinized a population-based cohort of 26 families from Finland that had screened mutation-negative by previous techniques. Blood was tested for allelic messenger RNA (mRNA) expression of MLH1, MSH2, and MSH6 by single nucleotide primer extension (SNuPE), and tumor tissue for MMR protein expression by immunohistochemistry (IHC) as well as for microsatellite instability (MSI). Full-length cDNAs of genes implicated by SNuPE or IHC were cloned and sequenced. RESULTS Unbalanced mRNA expression of MLH1 alleles was evident in two families. An inherited nonsense mutation was subsequently identified in one family, and complete silencing of the mutated allele was identified in the other family. Extinct protein expression by IHC implicated MLH1 in these two and in four other families, MSH2 in four families, and MSH6 in one family. Although no unequivocal genomic mutations were detected in the latter families, haplotype and other findings provided support for heritable defects. With one exception, all tumors with IHC alterations showed MSI, in contrast to the remaining families, which showed neither IHC changes nor MSI. CONCLUSION Our expression-based strategy stratified the present "mutation-negative" cohort into two discrete categories: families linked to the major MMR genes MLH1, MSH2, and MSH6 (11 [42%] of 26) and those likely to be associated with other, as yet unknown susceptibility genes (15 [58%] of 26).
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Affiliation(s)
- Elise Renkonen
- Department of Medical Genetics, University of Helsinki, Helsinki, Finland
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Wei SC, Yu CY, Tsai-Wu JJ, Su YN, Sheu JC, Wu CHH, Wang CY, Wong JM. Low mutation rate of hMSH2 and hMLH1 in Taiwanese hereditary non-polyposis colorectal cancer. Clin Genet 2003; 64:243-51. [PMID: 12919140 DOI: 10.1034/j.1399-0004.2003.00123.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Hereditary non-polyposis colorectal cancer (HNPCC), the most common type of hereditary colorectal cancer, is thought to be a simple Mendelian disease involving DNA mismatch repair genes. The majority of mutations associated with HNPCC occur in the hMSH2 and hMLH1 genes. The reported incidence of mismatch repair gene mutations in HNPCC kindreds varies considerably (from 22 to 86%), and most mutations are unique. This study aimed to determine the genetic basis of Taiwanese HNPCC kindreds, focusing on the two major genes involved in this disease. A total of 15 Taiwanese HNPCC kindreds meeting the Amsterdam criteria, including 72 affected individuals among a total of 266 individuals, were analyzed using both RNA- and DNA-based methods. The mutation rate of hMSH2 and hMLH1 in these 15 kindreds was 0% and 20%, respectively, which is lower than that reported in other countries. Two novel mutations were discovered in hMLH1: one was an allelic loss of a 5.2-kb genomic fragment causing exon 16 deletion; and the other was a two-nucleotide deletion that resulted in a frameshift mutation of exon 3. We also identified one hMLH1 exon 4 mutation (a C to T transition in codon 117), which had been reported previously in western countries. This is the first genetic study of HNPCC from Taiwan.
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Affiliation(s)
- S-C Wei
- Department of Internal Medicine, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan
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Häberle J, Denecke J, Schmidt E, Koch HG. Diagnosis of N-acetylglutamate synthase deficiency by use of cultured fibroblasts and avoidance of nonsense-mediated mRNA decay. J Inherit Metab Dis 2003; 26:601-5. [PMID: 14605506 DOI: 10.1023/a:1025912417548] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Molecular diagnosis of N-acetylglutamate synthase deficiency (NAGSD) has become possible now that the corresponding gene has been identified. We describe the genetic analysis of a patient with NAGSD using low-level transcripts derived from cultured fibroblasts. One defective allele (c.1306-1307insT) was detected by PCR amplification. However, the transcript from a second mutation (IVS3 - 2A>T), causing aberrant splicing with the generation of a premature termination codon, was not detected until interference of nonsense-mediated mRNA decay was abrogated by the translation inhibitor cycloheximide. We demonstrate that low-level transcripts in cells that do not express significant enzyme activity are a valuable tool for molecular studies of genetic alterations, and suggest routine abrogation of nonsense-mediated mRNA decay using cycloheximide when transcript analysis is performed.
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MESH Headings
- Acetyltransferases/deficiency
- Alleles
- Amino Acid Metabolism, Inborn Errors/diagnosis
- Amino Acid Metabolism, Inborn Errors/enzymology
- Amino Acid Metabolism, Inborn Errors/genetics
- Amino-Acid N-Acetyltransferase
- Cells, Cultured
- Codon/genetics
- Codon, Nonsense/genetics
- Cycloheximide
- DNA, Complementary/genetics
- Female
- Fibroblasts/enzymology
- Humans
- Infant, Newborn
- Protein Synthesis Inhibitors
- RNA, Messenger/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Transcription, Genetic/drug effects
- Transcription, Genetic/genetics
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Affiliation(s)
- J Häberle
- Universitätsklinikum Münster, Klinik und Poliklinik für Kinderheilkunde, Münster, Germany.
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