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71.
Two regions of homozygous deletion clusters at chromosome band 9p21 in human lung cancer 总被引:5,自引:0,他引:5
Hamada K Kohno T Takahashi M Yamazaki M Yamazaki M Tashiro H Sugawara C Ohwada S Sekido Y Minna JD Yokota J 《Genes, chromosomes & cancer》2000,27(3):308-318
We examined 149 lung cancer cell lines for homozygous deletions using 24 DNA markers, which were mapped and ordered in chromosome band 9p21, to define the target regions for 9p21 deletions in human lung cancer. Homozygous deletions were detected in 39 (26%) cell lines and clustered at 2 independent regions. One was the region containing the p16/CDKN2A tumor suppressor gene, and this region was deleted in 32 (21%) cell lines. The other was the region containing D9S171, which is the locus approximately 3 Mb proximal to the CDKN2A locus. This region, designated as the D9S171 region, was deleted in 18 (12%) cell lines. Seven of the 18 cell lines had identical minimum deletions of a 17,036 bp sequence located 20 kb distal to the D9S171 locus. However, such a deletion was also observed in the corresponding B-lymphoblastoid cell line from 1 of the 7 cell lines and in 5 (16%) of 32 noncancerous tissues, suggesting that the deletion was a genetic polymorphism. By considering this polymorphism, 11 (7%) cell lines still had deletions at the D9S171 region. Two NSCLC cell lines showed deletions at the D9S171 region and retentions of the CDKN2A locus. Furthermore, an NSCLC cell line showed discontinuous deletions including either the CDKN2A or D9S171 locus. Therefore, the region surrounding the D9S171 locus was defined as another target region for the 9p21 deletions. It is possible that unknown tumor suppressor gene(s) are present in this chromosomal region. Genes Chromosomes Cancer 27:308-318, 2000. 相似文献
72.
Saana Mnkre Liina Kuuluvainen Celia Kun-Rodrigues Susana Carmona Johanna Schleutker Jose Bras Minna Pyhnen Rita Guerreiro Liisa Myllykangas 《European journal of human genetics : EJHG》2021,29(4):663
Cerebral small vessel disease (CSVD) is the most important cause of vascular cognitive impairment (VCI). Most CSVD cases are sporadic but familial monogenic forms of the disorder have also been described. Despite the variants identified, many CSVD cases remain unexplained genetically. We used whole-exome sequencing in an attempt to identify novel gene variants underlying CSVD. A cohort of 35 Finnish patients with suspected CSVD was analyzed. Patients were screened negative for the most common variants affecting function in NOTCH3 in Finland (p.Arg133Cys and p.Arg182Cys). Whole-exome sequencing was performed to search for a genetic cause of CSVD. Our study resulted in the detection of possibly pathogenic variants or variants of unknown significance in genes known to associate with CSVD in six patients, accounting for 17% of cases. Those genes included NOTCH3, HTRA1, COL4A1, and COL4A2. We also identified variants with predicted pathogenic effect in genes associated with other neurological or stroke-related conditions in seven patients, accounting for 20% of cases. This study supports pathogenic roles of variants in COL4A1, COL4A2, and HTRA1 in CSVD and VCI. Our results also suggest that vascular pathogenic mechanisms are linked to neurodegenerative conditions and provide novel insights into the molecular basis of VCI.Subject terms: Stroke, Sequencing, Genetics research, Dementia 相似文献
73.
Kaisa Pyrhönen Simo Näyhä Minna Kaila Liisa Hiltunen Esa Läärä 《Pediatric allergy and immunology》2009,20(4):328-338
Food allergies (FAs) and hypersensitivities (FHSs) have rarely been studied in large unselected child populations. This population-based cross-sectional survey estimated the occurrence of FHS as perceived by parents and that of FA diagnosed by a physician among children aged 1–4 yr in south-eastern Finland. Before the scheduled annual follow-up visit to the local child health clinic, the parents of children who were born between 1 April, 2001 and 31 March, 2005, and living in the Province of South Karelia (data from Finnish Population Register) were mailed a questionnaire containing items on the child's background, physician-diagnosed FAs and FHSs perceived by the parents. The questionnaires were returned during the visit. Three thousand three hundred and eight (69%) out of the 4779 questionnaires were returned. The lifetime prevalence of physician-diagnosed FAs was 9%. In an additional 21%, FHSs were perceived by the parents only. In a further 19% at least one food item had been eliminated from the diet without any perception of symptoms, this proportion having a downward trend by age. Physician-diagnosed FAs were more common in boys than in girls. Cow's milk was the most commonly reported cause of food-associated symptoms (13% of all children). One-third of the children aged 1–4 yr suffered from food-associated symptoms, and in an additional fifth at least one food item had been eliminated from their diet, implying that every other child had possibly been subjected to some form of elimination diet. 相似文献
74.
Seija Alanen Maritta Välimäki Minna Kaila for the ECCE Study Group 《Journal of clinical nursing》2009,18(18):2613-2621
Aims. The aim of the study was to address the following questions: What kind of experiences do primary care nurses have of guideline implementation? What do nurses think are the most important factors affecting the adoption of guidelines? Background. The implementation of clinical guidelines seems to be dependent on multiple context‐specific factors. This study sets out to explore the experiences of primary care nurses concerning guideline implementation. Design. Qualitative interview. Methods. Data were generated by four focus group interviews involving nurses working in out‐patient services in primary health centres in Finland. Purposive sampling was used to select health centres. Inductive content analysis was used to identify themes emerging from the data. Results. Four main groups of factors were identified from the analysis of data: (i) factors related to the organisation, (ii) factors related to nurses, (iii) factors related to the anticipated consequences and (iv) factors related to the patient group. Nurses’ awareness and acceptance of guidelines and the anticipated positive consequences facilitate the implementation of guidelines. Organisational support, especially the adapting of guidelines to local circumstances, seems to be crucial for successful implementation. Conclusions. Clinical guidelines can be promising tools in enhancing evidence‐based nursing practice, as nurses see them as practical work tools in patient care and so are willing to adopt them. However, support from management and physicians is needed to ensure the successful implementation of guidelines into nursing practices. Relevance to clinical practice. Based on the findings of this study and previous knowledge of guideline implementation some practical recommendations are suggested. Select the most relevant guidelines to clinical practice, organise the adaptation of guidelines to local circumstances, inform all practitioners involved in treatment and give clear instructions for the adoption of the guidelines. 相似文献
75.
Genetic risk determines the emergence of diabetes-associated autoantibodies in young children 总被引:5,自引:0,他引:5
Kupila A Keskinen P Simell T Erkkilä S Arvilommi P Korhonen S Kimpimäki T Sjöroos M Ronkainen M Ilonen J Knip M Simell O 《Diabetes》2002,51(3):646-651
Timing of onset of autoimmunity is a prerequisite for unmasking triggers and pathogenesis of type 1 diabetes. We followed 4,590 consecutive newborns with 8 or 3% HLA-DQB1 conferred risk for type 1 diabetes at 3-, 6-, or 12-month intervals up to 5.5 years of age. Islet cell autoantibodies (ICAs) and, in the 137 children with ICAs, insulin autoantibodies (IAAs), GAD65 autoantibodies (GADAs), and IA-2 protein autoantibodies (IA-2As) were measured. Children with high genetic risk developed ICAs more often than those with moderate risk (log-rank P = 0.0015); 85 and 91% remained ICA negative by 5 years of age, respectively. The time of appearance of biochemical autoantibodies was then compared with the appearance of ICAs. IAAs and GADAs emerged usually before ICAs (means -1.8 and -1.5 months, respectively) and IA-2As after ICAs (mean 2.0 months). Ninety-five percent of all IAAs, GADAs, and IA-2As seroconversions occurred in a cluster (-12 to 8 months) around the ICA seroconversion. We conclude that diabetes-associated autoantibodies emerged in children with predisposing HLA-DQB1 alleles after 3 months of age at a constant tempo, determined by the genetic risk level, usually in the order of IAA, GADA, ICA, and IA-2A. Seroconversion to multiple autoantibody positivity usually occurred tightly clustered in time. 相似文献
76.
Partanen T Johansson M Ahrens W Sala M Wesseling C Boffetta P Brenes F Font C Frentzel-Beyme R Garau I Janer G Kallas-Tarpila T Kogevinas M Loponen M Østergren L Peltomäki P Solér MD Svanström L Tempel J Neuvonen K 《Preventive medicine》2002,35(3):232-240
BACKGROUND: A simple empirically based method for assessment of the feasibility of workplace health promotion programs is described, focusing on cancer hazards (lifestyles, workplace hazards, deficient early detection). The basic components of feasibility are addressed: extent of hazards; needs of employees for hazard reduction and acceptability of WHP; and social context. METHODS: The procedure consists of six modules: guidelines on feasibility assessment; employee questionnaire; interview checklists for probing attitudes of management and partners (social context); data form; debriefing; and assessment of feasibility. Pretesting was completed in 16 workplace communities representing industry, construction, transport, telecommunications, health care, lodging and catering, teaching, and municipality jobs in five countries; a total of 1,085 subjects completed the employee questionnaire on health hazards, needs, and acceptability. RESULTS: The method demonstrated its utility in obtaining and summarizing the necessary data. Feasibility was assessed for the 16 test communities. CONCLUSION: The procedure can be customized; it has a high degree of face validity or understandability, and it is applicable in a wide variety of settings. 相似文献
77.
The RASSF1A tumor suppressor gene is inactivated in prostate tumors and suppresses growth of prostate carcinoma cells 总被引:13,自引:0,他引:13
78.
Zhu Y Spitz MR Strom S Tomlinson GE Amos CI Minna JD Wu X 《International journal of cancer. Journal international du cancer》2002,102(5):536-540
Cytogenetic aberrations on chromosome 9 have been reported to be one of the most frequent genetic changes in lung tumorigenesis. Although many of these changes have been detected in lung carcinoma specimens, there is growing evidence showing the concordance between chromosomal alterations in primary lung tumors and peripheral blood lymphocytes (PBLs). We investigated whether spontaneous aberrations on chromosome 9 in PBLs are associated with the presence of lung cancer and with a family history of cancer. A personal interview, to construct a detailed epidemiologic profile including family history of cancer, was conducted on 174 lung cancer cases and 162 matched controls. One hundred metaphases from PBLs of each subject were analyzed for chromosome 9 aberrations using the whole chromosome painting technique. Overall, the mean proportion of individuals with chromosome 9 abnormalities in their PBLs was significantly higher in cases (96.0%) than in controls (60.5%) (p < 0.05). After adjustment by age, gender, ethnicity, family size, and pack-years, there was a 16.63-fold significantly elevated odds ratio (OR) for lung cancer associated with chromosome 9 aberrations. When subjects were categorized by frequencies of the chromosome 9 lesions, we observed significantly increased odds ratios of 11.13 (4.66, 26.58) and 27.45 (11.15, 67.54) for individuals with 1 chromosome 9 aberration and >/=2 chromosome 9 aberrations, respectively. By performing family history analyses, we further observed that control individuals with chromosome 9 aberrations were more likely to report a family history of any cancer (OR = 1.67 [0.84, 3.32]) and lung cancer (OR = 2.49 [0.81, 7.67]). Our findings suggest that chromosome 9 aberrations in PBLs might be considered a marker of lung cancer predisposition and may be associated with familial aggregation of cancer. 相似文献
79.
Dallol A Forgacs E Martinez A Sekido Y Walker R Kishida T Rabbitts P Maher ER Minna JD Latif F 《Oncogene》2002,21(19):3020-3028
The human homologue of the Drosophila Roundabout gene DUTT1 (Deleted in U Twenty Twenty) or ROBO1 (Locus Link ID 6091), a member of the NCAM family of receptors, was recently cloned from the lung cancer tumour suppressor gene region 2 (LCTSGR2 or U2020 region) at 3p12. DUTT1 maps within a region of overlapping homozygous deletions characterized in both small cell lung cancer lines (SCLC) and in a breast cancer line. In this report we (a) defined the genomic organization of the DUTT1 gene, (b) performed mutation and expression analysis of DUTT1 in lung, breast and kidney cancers, (c) identified tumour specific promoter region methylation of DUTT1 in human cancers. The gene was found to contain 29 exons and spans at least 240 kb of genomic sequence. The 5' region contains a CpG island, and the poly(A)(+) tail has an atypical 5'-GATAAA-3' signal. We analysed DUTT1 for mutations in lung, breast and kidney cancers, no inactivating mutations were detected by PCR-SSCP. However, seven germline missense changes were found and characterized. DUTT1 expression was not detectable in one out of 18 breast tumour lines analysed by RT-PCR. Bisulfite sequencing of the promoter region of DUTT1 gene in the HTB-19 breast tumour cell line (not expressing DUTT1) showed complete hypermethylation of CpG sites within the promoter region of the DUTT1 gene (-244 to +27 relative to the translation start site). The expression of DUTT1 gene was reactivated in HTB-19 after treatment with the demethylating agent 5-aza-2'-deoxycytidine. The same region was also found to be hypermethylated in six out of 32 (19%) primary invasive breast carcinomas and eight out of 44 (18%) primary clear cell renal cell carcinomas (CC-RCC) and in one out of 26 (4%) primary NSCLC tumours. Furthermore 80% of breast and 75% of CC-RCC tumours showing DUTT1 methylation had allelic losses for 3p12 markers hence obeying Knudson's two hit hypothesis. Our findings suggest that DUTT1 warrants further analysis as a candidate for the tumour suppressor gene (TSG) at 3p12, a region defined by hemi and homozygous deletions and functional analysis. 相似文献
80.
BRAF and RAS mutations in human lung cancer and melanoma 总被引:22,自引:0,他引:22
Brose MS Volpe P Feldman M Kumar M Rishi I Gerrero R Einhorn E Herlyn M Minna J Nicholson A Roth JA Albelda SM Davies H Cox C Brignell G Stephens P Futreal PA Wooster R Stratton MR Weber BL 《Cancer research》2002,62(23):6997-7000
BRAF encodes a RAS-regulated kinase that mediates cell growth and malignant transformation kinase pathway activation. Recently, we have identified activating BRAF mutations in 66% of melanomas and a smaller percentage of many other human cancers. To determine whether BRAF mutations account for the MAP kinase pathway activation common in non-small cell lung carcinomas (NSCLCs) and to extend the initial findings in melanoma, we screened DNA from 179 NSCLCs and 35 melanomas for BRAF mutations (exons 11 and 15). We identified BRAF mutations in 5 NSCLCs (3%; one V599 and four non-V599) and 22 melanomas (63%; 21 V599 and 1 non-V599). Three BRAF mutations identified in this study are novel, altering residues important in AKT-mediated BRAF phosphorylation and suggesting that disruption of AKT-induced BRAF inhibition can play a role in malignant transformation. To our knowledge, this is the first report of mutations documenting this interaction in human cancers. Although >90% of BRAF mutations in melanoma involve codon 599 (57 of 60), 8 of 9 BRAF mutations reported to date in NSCLC are non-V599 (89%; P < 10(-7)), strongly suggesting that BRAF mutations in NSCLC are qualitatively different from those in melanoma; thus, there may be therapeutic differences between lung cancer and melanoma in response to RAF inhibitors. Although uncommon, BRAF mutations in human lung cancers may identify a subset of tumors sensitive to targeted therapy. 相似文献