Mutation Status (mutation + status)

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Mutation Status

  • egfr mutation status


  • Selected Abstracts


    Characterization of hepatitis B virus reverse transcriptase sequences in Chinese treatment naive patients

    JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 8 2009
    Yue Han
    Abstract Background and Aims:, The hepatitis B virus (HBV) reverse transcriptase (RT) plays an important role in viral replication. The aim of the present study was to characterize profiles of the RT region and to construct a database for further studies. Methods:, Serum samples were obtained from 328 treatment naive patients chronically infected with HBV in five Chinese cities. Mutation status, genotypes and deep sequence analysis were carried out by amplifying and sequencing the RT region. Results:, The base usage in the RT region differed at the mono- and dinucleotide level and thymidine dominated. The higher the variability of the strain was, the more it replicated. No significant clustering was found between our HBV RT sequences and those isolated 10 years ago (achieved from genebank). Nucleotide analogue resistance related mutants exist. The M204V/I mutation was found in 1.8% of the strains, 1.2% had L180M+ M204V/I, 0.6% had A181T/V, and only one had all three mutations. Minor strain mutants were found in 9.3% of the samples studied. The genotype B patients made up 36.6% (88.7% B2) and were mostly found in southern China, 63.4% (92.2% C2) were genotype C, and only one was genotype D. The average age of HBeAg positive genotype B patients was 29.5 ± 10.4 years, for genotype C it was 36.1 ± 10.9 (P < 0.001). Conclusion:, Primarily antiviral resistance related mutant strains do exist in treatment naïve patients. Without antiviral pressure, HBV strains evolved at a normal speed. In depth sequence analysis implied that viral replication might be correlated with its variability, which needs to be further investigated. [source]


    Cytogenetic abnormalities in essential thrombocythemia: prevalence and prognostic significance

    EUROPEAN JOURNAL OF HAEMATOLOGY, Issue 1 2009
    Naseema Gangat
    Abstract Objectives:, In the current study we describe cytogenetic findings as well as clinical correlates and long-term prognostic relevance of abnormal cytogenetics at the time of diagnosis of essential thrombocythemia (ET). Patients and methods:, The study cohort consisted of a consecutive group of patients with ET who fulfilled the World Health Organization diagnostic criteria, and in whom cytogenetic analysis was performed at diagnosis. Results:, A total of 402 patients were studied (median age, 56 yrs; median follow-up 70 months). The prevalence of abnormal cytogenetics at diagnosis was 7% (28 of 402). The most common cytogenetic anomalies were trisomy 9 (four patients), abnormal chromosome 1 (three patients) and trisomy 8 (two patients). Parameters at diagnosis that were significantly associated with abnormal cytogenetics included palpable splenomegaly (P = 0.03), current tobacco use (P = 0.04); venous thrombosis (P = 0.02), and anemia with a hemoglobin of <10 g/dL (P = 0.02); but did not include JAK2V617F mutation status, or advanced age. During follow up, patients with abnormal cytogenetics did not have shorter survival, or increased transformation to acute leukemia or myelofibrosis. Conclusion:, Cytogenetic anomalies at diagnosis are relatively uncommon in ET, and do not predict evolution into more aggressive myeloid disorders, or inferior survival. [source]


    Association of polymorphisms in the interleukin-18 gene in patients with Crohn's disease depending on the CARD15/NOD2 genotype

    INFLAMMATORY BOWEL DISEASES, Issue 12 2005
    Jürgen Glas MD
    Abstract Background: An increased expression of interleukin-18 (IL-18), a proinflammatory cytokine inducing interferon-,, has been found in Crohn's disease (CD). In the IL-18 gene, several partly functional relevant polymorphisms are known. This study sought to investigate associations of IL-18 polymorphisms in inflammatory bowel disease and CD according to CARD15/NOD2 mutation status and clinical phenotypes. Methods: The IL-18 polymorphisms ,607, ,137, and the third position of codon 35 (c35/3) were genotyped in 210 patients with CD, 140 patients with ulcerative colitis, and 265 healthy controls using polymerase chain reaction and restriction fragment length polymorphism analysis. Results: Frequencies of alleles and genotypes of the 3 polymorphisms and of the respective haplotypes and diplotypes displayed no significant differences between the whole groups of patients with CD and ulcerative colitis, respectively, compared with the controls. After stratification of patients with CD for CARD15/NOD2 status, significant associations of genotypes ,137 CC (P = 0.018) and c35/3 CC (P = 0.010) and of the diplotype 2-2 (P = 0.018) were found in cases carrying CARD15/NOD2 mutations. Associations of genotypes ,137 GG (P = 0.015) and c35/3 AA (P = 0.030) with colonic disease only in cases positive for CARD15/NOD2 mutations and of the genotype ,607 AA (P = 0.007) with fistulas in cases negative for CARD15/NOD2 mutations were observed. Conclusions: In this study, significant differences of several genotypes and diplotypes within the IL-18 gene in CD depending on CARD15/NOD2 status have been found. In context with an increased expression of IL-18 in CD, it remains to be shown whether the expression of IL-18 is influenced by CARD15/NOD2 mutation status. [source]


    Distinct CpG island methylation profiles and BRAF mutation status in serrated and adenomatous colorectal polyps

    INTERNATIONAL JOURNAL OF CANCER, Issue 11 2008
    Yong Ho Kim
    Abstract A subset of colorectal cancers with CpG island methylator phenotype-high (CIMP-H) is frequently associated with MSI and BRAF V600E mutation. Since limited data are available on different histological types of colorectal polyps, we compared the pattern and the frequency of promoter methylation, CIMP-H, MSI, KRAS and BRAF V600E mutations and the relationship among these molecular parameters and the clinicopathologic characteristics in 110 serrated polyps (48 hyperplastic polyps, 32 sessile serrated adenomas and 30 serrated adenomas) and 32 tubular adenomas using 7 commonly used tumor-associated gene loci. No significant difference in the frequency of overall methylation frequency (86% vs. 100%) and CIMP-H (39% vs. 28%) between serrated polyps and tubular adenomas was observed, but proximally located serrated polyps showed more frequent methylation at 5 of 7 loci examined, and were more likely to be CIMP-H (62% vs. 22%). MGMT methylation was more common in tubular adenomas while MLH1 and HIC1 were more frequently methylated in serrated polyps. BRAF mutation was frequently present in all types of serrated polyps (80%), but was absent in tubular adenomas and was not associated with CIMP or MSI status. These results show comparable frequencies of promoter methylation of tumor-associated genes and CIMP-H, but distinct differences in gene-specific or colonic site-specific methylation profiles occur in serrated polyps and tubular adenomas. BRAF mutation occurs independently of CIMP and MSI in all types of serrated polyps and may serve as a marker of serrated pathway of colorectal carcinogenesis. © 2008 Wiley-Liss, Inc. [source]


    Thymidylate synthase polymorphisms and colon cancer: Associations with tumor stage, tumor characteristics and survival

    INTERNATIONAL JOURNAL OF CANCER, Issue 10 2007
    Karen Curtin
    Abstract Thymidylate synthase (TS) is a key enzyme in folate metabolism, a pathway that is important in colorectal carcinogenesis. We investigated the role of functional polymorphisms in the TS 5,-UTR promoter enhancer region (TSER, 3 or 2 repeats of a 28-bp sequence) and the 3,-UTR (1494delTTAAAG) and their association with colon tumor characteristics, including tumor stage and acquired mutations in p53, Ki- ras and microsatellite instability. Data from a population-based incident case,control colon cancer study in northern California, Utah and Minnesota (1,206 cases, 1,962 controls) was analyzed using unordered polytomous logistic regression models. In both men and women, individuals with variant TS alleles were at reduced risk of having an advanced stage tumor (metastatic disease: OR = 0.35, 95% CI: 0.2,0.6 vs. wildtype TSER and 3,-UTR). Stage-adjusted survival did not differ by genotype. Men with 1 or 2 variant alleles in both the TSER and 3,-UTR genotypes had a 50% reduced risk of a p53 -positive tumor (OR = 0.5, 95% CI: 0.3,0.9 vs. homozygous wildtype TSER and 3,-UTR). Women with 1 or 2 variant alleles for either the TSER or 3,-UTR polymorphism had reduced risk of having any colon tumor that did not vary by mutation status. This study provides some support for associations between TS genotype and colon cancer tumor characteristics. © 2007 Wiley-Liss, Inc. [source]


    Usefulness of EGFR mutation screening in pleural fluid to predict the clinical outcome of gefitinib treated patients with lung cancer

    INTERNATIONAL JOURNAL OF CANCER, Issue 10 2006
    Junichi Soh
    Abstract The importance of epidermal growth factor receptor (EGFR) gene mutation has been recognized in nonsmall cell lung cancer (NSCLC), requiring the standardization of mutation screening system including the kind of samples. Here, we examined the EGFR mutation status in 61 pleural fluid samples from NSCLC cases using direct sequencing, nonenriched PCR, mutant-enriched PCR and peptide nucleic acid-locked nucleic acid (PNA-LNA) PCR clamp assay. The mutant-enriched PCR assay detected 16 mutant cases. Among them, the nonenriched PCR assay failed to detect 3 mutant cases. Regarding the discrepancy between mutant-enriched PCR and PNA-LNA PCR clamp assays, 3 cases of exon19-deletions were detected only by mutant-enriched PCR assay and no difference at the L858R mutation. There was no difference in results between direct sequencing and nonenriched PCR assay. We also correlated the EGFR mutation with clinical outcome of gefitinib-treated 29 cases. EGFR mutations were present in 10 cases, revealing 7 partial response and 3 no change (NC). In EGFR wild-type cases, 10 revealed NC and 9 progressive disease. The responders were significantly more frequent among the EGFR mutant cases than among the wild-type (p < 0.0001). Overall survival (p = 0.0092) and progression-free survival (p = 0.018) were significantly longer among the EGFR mutant cases than among the wild-type. In summary, we evaluated the utility of EGFR mutation screening in pleural fluid using 4 assays that showed some discrepancies arising from the designs of the assays. As clinical importance, the EGFR mutation status in pleural fluid can be a biomarker for the favorable outcome of gefitinib-treated NSCLC cases. © 2006 Wiley-Liss, Inc. [source]


    Role of RFLP using TspRI for carrier detection in Glanzmann's thrombasthenia: a report on two families

    INTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 1p1 2010
    M. KANNAN
    Summary Glanzmann's thrombasthenia (GT) was diagnosed in two patients who presented with bleeding manifestations accompanied by absent platelet aggregation, secondary to adenosine-5'-diphosphate, adrenaline, arachidonic acid and collagen. Flow cytometry analysis for GPIIb/IIIa expression was done using CD61 and CD41 markers in these patients and their family members including siblings. The patients were sub typed as Type I as he had absent glycoproteins (GP) IIb/IIIa. Family studies by flow cytometry showed reduced GPII/IIIa expression in both the parents and one sibling. However, western blot showed abnormal GPIIb protein in all the family members including siblings. It is possible that abnormal GPIIb protein by western blot in family members may reflect their carrier status. Patients' DNA was analyzed for mutation in both the GPIIb and GPIIIa genes by conformational sensitive gel electrophoresis (CSGE), followed by sequencing. CSGE showed defect in exon 12 and the promoter region of GPIIb. By sequence, it was confirmed that both the mutations were homozygous one was c.1028T>C and the other one was M33320.1:g.951G>A. For one of these mutations, restriction fragment length polymorphism (RFLP) was developed to look for the same mutation in all the family members. RFLP was developed using a restriction enzyme (TspRI) against the patient's mutation, c.1028T>C in exon 12 of GPIIb gene. RFLP followed by gel electrophoresis revealed that the mutation was heterozygous in all the family members. The findings by RFLP were double confirmed by direct DNA sequencing of the exon 12 in all the family members. Thus, TspRI marker may be used as a RFLP marker to predict the carriers in GT families, if the patients' mutation status is identified. [source]


    Soluble syndecan-1 (sCD138) as a prognostic factor independent of mutation status in patients with chronic lymphocytic leukemia

    INTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 1 2009
    I. JILANI
    Summary Syndecan-1 (sCD138) is a transmembrane heparan sulfate-bearing proteoglycan expressed in epithelial cells as well as hematopoietic cells that demonstrate plasmacytoid differentiation. Higher levels of sCD138 correlate with poor outcome in myeloma. We examined the association of circulating sCD138 levels in plasma with clinical behavior in 104 patients with chronic lymphocytic leukemia. sCD138 levels were significantly higher in patients (median, 52.8 ng/ml; range, 13.4,252.7 ng/ml) than in healthy control subjects (median, 19.86; range, 14.49,33.14 ng/ml) (P < 0.01). Elevated sCD138 (>median, 52.8 ng/ml) was associated with significantly shorter survival (P = 0.0004); this association was independent of IgVH mutation status, ,2-microglobulin (,2-M) level, and treatment history. Patients with mutated IgVH but high sCD138 levels (>52.8 ng/ml) had significantly shorter survival than those with mutated IgVH and lower levels of sCD138. Similarly, patients with unmutated IgVH but high sCD138 levels had significantly shorter survival than those with lower sCD138 levels and unmutated IgVH (P = 0.007). In a multivariate Cox regression model, only Rai stage, ,2-M, and sCD138 remained predictors of survival. These data suggest that sCD138 when combined with ,2-M and Rai stage, may replace the need for testing IgVH mutation status. [source]


    Surveillance for Early Detection of Aggressive Parathyroid Disease: Carcinoma and Atypical Adenoma in Familial Isolated Hyperparathyroidism Associated With a Germline HRPT2 Mutation,,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 10 2006
    Thomas G Kelly
    Abstract Familial hyperparathyroid syndromes involving mutations of HRPT2 (also CDC73), a tumor suppressor, are important to identify because the relatively high incidence of parathyroid malignancy associated with such mutations warrants a specific surveillance strategy. However, there is a dearth of reports describing experience with surveillance and early detection informed by genetic insight into this disorder. Introduction: Familial isolated hyperparathyroidism (FIHP) is a rare cause of parathyroid (PT) tumors without other neoplasms or endocrinopathies. Germline mutations in CASR, MEN1, and rarely, HRPT2 have been identified in kindreds with FIHP. HRPT2 mutations may be enriched in FIHP families with PT carcinoma, underscoring the importance of identifying causative mutations. Materials and Methods: A 13-year-old boy, whose father had died of PT carcinoma, developed primary hyperparathyroidism. A left superior PT mass was identified by ultrasonography and removed surgically. Aggressive histological features of the boy's tumor included fibrous trabeculae, mitoses, and microscopic capsular infiltration. Two years later, under close biochemical surveillance, primary hyperparathyroidism recurred 5 months after documentation of normocalcemia and normal parathyroid status. Ultrasound and MRI identified a newly enlarged right superior PT gland but indicated no recurrent disease in the left neck. Histologic features typical of a benign adenoma were evident after surgical extirpation of the gland. Results: Leukocyte DNA analysis revealed a frameshift mutation in exon 2 of HRPT2. The initial tumor manifested the expected germline HRPT2 mutation, plus a distinct somatic frameshift mutation, consistent with the Knudson "two hit" concept of biallelic inactivation of a classic tumor suppressor gene. Genetic screening of the patient's 7 asymptomatic and previously normocalcemic siblings revealed three with the same germline HRPT2 mutation. One of the siblings newly identified as mutation-positive was noted to be hypercalcemic at the time of the genetic screening. He was found to have a PT adenoma with aggressive features. Two of the five children of another mutation-positive sibling also carry the same HRPT2 mutation. Conclusions: Despite the reported rarity of HRPT2 mutations in FIHP, a personal or family history of PT carcinoma in FIHP mandates serious consideration of germline HRPT2 mutation status. This information can be used in diagnostic and management considerations, leading to early detection and removal of potentially malignant parathyroid tumors. [source]


    Stratum corneum lipids, skin barrier function and filaggrin mutations in patients with atopic eczema

    ALLERGY, Issue 7 2010
    J. M. Jungersted
    To cite this article: Jungersted JM, Scheer H, Mempel M, Baurecht H, Cifuentes L, Høgh JK, Hellgren LI, Jemec GBE, Agner T, Weidinger S. Stratum corneum lipids, skin barrier function and filaggrin mutations in patients with atopic eczema. Allergy 2010; 65: 911,918. Abstract Background:, Prior to the discovery of filaggrin (FLG) mutations, evidence for an impaired skin barrier in atopic dermatitis (AD) has been documented, and changes in ceramide profile, altered skin pH and increased trans-epidermal water loss (TEWL) in patients with AD have been reported. Until now, no studies have analysed stratum corneum (SC) lipids combined with skin barrier parameters in subjects of known FLG genotype. Methods:, A cohort of 49 German individuals genotyped for the most common FLG mutations (R501X, 2282del4) had SC samples taken for lipid analysis by high-performance thin layer chromatography. In addition, TEWL, erythema, skin hydration and pH were measured. In 27 of the 49 individuals, a 24-h irritation patch test with sodium lauryl sulphate was performed. For the analysis, both the AD group and the control group were stratified by FLG mutation status (FLGmut/FLGwt). Results:, In the FLGmut AD group, significantly lower levels of ceramide 4 and significantly higher levels of ceramide 7 were observed when compared to both healthy control groups. However, ceramide 7 levels also significantly differed between FLGwt AD and FLGwt controls, as did ceramide 1 levels. No significant differences were observed for ceramide 2, 3, 5 and 6. FLGmut individuals had significantly higher skin pH values than individuals not carrying FLG mutations. Patients with AD with FLG mutations had significantly higher erythema compared to patients with AD without FLG mutations. Conclusion:, Our results confirm previous observations of altered ceramide levels in AD, which however appear to show no clear relationship with FLG mutations. [source]


    Prodromal myeloproliferative neoplasms: The 2008 WHO classification,

    AMERICAN JOURNAL OF HEMATOLOGY, Issue 1 2010
    Hans Michael Kvasnicka
    The concept of prodromal chronic myeloproliferative neoplasms has been endorsed by the WHO classification implicating a stepwise evolution of disease. Histology of the bone marrow (BM) and borderline to mildly expressed clinical features play a pivotal role for diagnosing prefibrotic-early primary myelofibrosis. By lowering the platelet count for essential thrombocythemia and regarding BM morphology, early manifestations are tackled. Pre-polycythemic stages of polycythemia vera with a low hemoglobin level at onset are diagnosed by positive JAK2V617F mutation status, a low erythropoietin value, and characteristic BM features. The revised WHO classification incorporates hematological, morphological, and moleculargenetic parameters to generate a consensus-based working diagnosis. Am. J. Hematol., 2010. © 2009 Wiley-Liss, Inc. [source]


    ERK-regulated differential expression of the Mitf 6a/b splicing isoforms in melanoma

    PIGMENT CELL & MELANOMA RESEARCH, Issue 1 2010
    Aline Primot
    Summary The master regulator of the melanocyte lineage Mitf is intimately involved in development as well as melanoma, controlling cell survival, differentiation, proliferation and metastasis/migration. Consistent with its central role, Mitf expression and Mitf post-translational modifications are tightly regulated. An additional potential level of regulation is afforded by differential splicing of Mitf exon-6 leading to the generation of two isoforms that differ by the presence of six amino-acids in the Mitf (+) isoform and which have differential effects on cell cycle progression. However, whether the ratio of the two isoforms is regulated and whether their expression correlates with melanoma progression is not known. Here, we show that the differential expression of the Mitf 6a/b isoforms is dependent on the MAPKinase signalling, being linked to the activation of MEK1-ERK2, but not to N-RAS/B-RAF mutation status. In addition, quantification of Mitf 6a/b splicing forms in 86 melanoma samples revealed substantially increased levels of the Mitf (,) form in a subset of metastatic melanomas. The results suggest that differential expression of the Mitf 6a/b isoforms may represent an additional mechanism for regulating Mitf function and melanoma biology. [source]


    Differentially expressed proteins in gastrointestinal stromal tumors with KIT and PDGFRA mutations

    PROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 4 2006
    Hyun Ju Kang
    Abstract Most gastrointestinal stromal tumors (GIST) have activating mutations in either KIT or PDGFRA. However, a small subset of GIST lacks either mutation. To investigate the molecular characteristics of GIST according to mutation type, protein expression profiles in 12 GIST (2 cases with PDGFRA mutations, 8 cases with KIT mutations and 2 cases lacking either mutation) were analyzed using 2-DE and MALDI-TOF-MS. Comparative analysis of the respective spot patterns using 2-DE showed that 15 proteins were differently expressed according to the mutation status. Expression levels of septin and heat shock protein (HSP) 27 were increased in GIST with KIT mutations and annexin V was overexpressed in GIST lacking either mutation. Among the 15 proteins, overexpression of 5 proteins [annexin V, high mobility group protein 1 (HMGB1), C13orf2, glutamate dehydrogenase 1 and fibrinogen beta chain] and decreased expression of RoXaN correlated with a higher tumor grade. These findings suggest that differential protein expression can be used as a diagnostic biomarker. Moreover, it may play a role in the development and progression of GIST according to activating mutation type, as these proteins have been shown to be involved in tumor metastasis, apoptosis and immune response. [source]


    Evaluation of the needs and concerns of partners of women at high risk of developing breast/ovarian cancer

    PSYCHO-ONCOLOGY, Issue 2 2006
    Shab Mireskandari
    Abstract This exploratory study investigates the experience of partners of women at high risk of developing breast/ovarian cancer and reports on the partners' views concerning their relationship, communication, future planning, children and childbearing, involvement in decision-making regarding screening and prophylactic measures, and information and support needs. In-depth interviews were conducted with 15 partners. Of these, seven were partners of women who were BRCA1/2 mutation carriers, five were partners of women with unknown mutation status, and three were partners of women who were non-carriers. None of the women had a previous diagnosis of breast or ovarian cancer. Partners of carriers and women with unknown mutation status were found to be more distressed than partners of non-carriers, with partners of mutation carriers reporting the most difficulties. Factors associated with better adjustment and coping for partners included dealing with this situation as a team with their wife, greater involvement in decision-making, satisfaction with their supportive roles and being optimistic. Decision-making difficulties in relation to prophylactic measures, concerns about their children possibly being at increased cancer risk, as well as the need to receive information directly from health professionals and the wish to meet other partners were also discussed. Copyright © 2005 John Wiley & Sons, Ltd. [source]


    FGFR3 protein expression and its relationship to mutation status and prognostic variables in bladder cancer,

    THE JOURNAL OF PATHOLOGY, Issue 1 2007
    DC Tomlinson
    Abstract FGFR3 is frequently activated by mutation in urothelial carcinoma (UC) and represents a potential target for therapy. In multiple myeloma, both over-expression and mutation of FGFR3 contribute to tumour development. To define the population of UC patients who may benefit from FGFR-targeted therapy, we assessed both mutation and receptor over-expression in primary UCs from a population of new patients. Manual or laser capture microdissection was used to isolate pure tumour cell populations. Where present, non-invasive and invasive components in the same section were microdissected. A screen of the region of the highest tumour stage in each sample yielded a mutation frequency of 42%. Mutations comprised 61 single and five double mutations, all in hotspot codons previously identified in UC. There was a significant association of mutation with low tumour grade and stage. Subsequently, non-invasive areas from the 43 tumours with both non-invasive and invasive components were analysed separately; 18 of these had mutation in at least one region, including nine with mutation in all regions examined, eight with mutation in only the non-invasive component and one with different mutations in different regions. Of the eight with mutation in only the non-invasive component, six were predicted to represent a single tumour and two showed morphological dissimilarity of fragments within the block, indicating the possible presence of distinct tumour clones. Immunohistochemistry showed over-expression of FGFR3 protein in many tumours compared to normal bladder and ureteric controls. Increased expression was associated with mutation (85% of mutant tumours showed high-level expression). Overall, 42% of tumours with no detectable mutation showed over-expression, including many muscle-invasive tumours. This may represent a non-mutant subset of tumours in which FGFR3 signalling contributes to the transformed phenotype and which may benefit from FGFR-targeted therapies. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source]


    Discriminating functional and non-functional p53 in human tumours by p53 and MDM2 immunohistochemistry

    THE JOURNAL OF PATHOLOGY, Issue 3 2005
    R Nenutil
    Abstract Mutation and/or loss of the TP53 tumour suppressor gene is the single most common genetic abnormality in human cancer. The majority of TP53 mutations lead to stabilization of the protein, so that immunohistochemical staining for p53 can suggest mutation status in many cases. However, various false-positive and false-negative situations mean that simple immunostaining for p53 is not informative in a substantial number of tumours. In the present study, a series of 119 human cancers were immunostained using a highly sensitive technique that detects the low levels of wild-type protein expressed in normal cells, such that homozygous gene deletion or non-sense TP53 mutation can be identified by an absence of staining. TP53 gene status was also assessed using FASAY as a genetic/functional screen and in selected cases by direct sequencing. A quantitative scoring system was employed to assess p53 levels, and p53 post-translational modification was evaluated using antibodies that detect specific phosphorylation sites. Phosphorylated p53 correlated with total p53 levels and did not improve the prediction of TP53 mutation status. The transcriptional activity of TP53 was determined by staining for two downstream target genes, p21WAF1 and MDM2, and statistical correlations between MDM2/p21WAF1 and p53 were found in tumours with wild-type, but not mutant TP53. Measurement of staining for p53 and MDM2 accurately identifies the TP53 status of tumours. This simple and cost-effective method, applicable to automated staining and quantitation methods, improves the identification of TP53 status over standard methods for p53 immunostaining and provides information about tumour p53 phenotype that is complementary to genotyping data. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source]


    Distinct promoter hypermethylation of p16INK4a, CDH1, and RAR-beta in intestinal, diffuse,adherent, and diffuse,scattered type gastric carcinomas

    THE JOURNAL OF PATHOLOGY, Issue 1 2002
    Naohide Oue
    Abstract Hypermethylation of CpG islands in gene promoters is associated with silencing of various tumour suppressor genes. Recent studies of colorectal and gastric carcinomas have defined a CpG island methylator phenotype (CIMP), which involves the targeting of multiple genes by promoter hypermethylation. In this study, methylation-specific polymerase chain reaction (PCR) was performed to study methylation of CpG islands in the promoters of the p16INK4a, cadherin 1 (CDH1), and retinoic acid receptor-beta (RAR-beta) genes in 45 gastric carcinomas and to investigate whether CDH1 and RAR-beta promoter hypermethylation is associated with CIMP-positive gastric carcinoma. CpG island hypermethylation of the p16INK4a, CDH1, and RAR-beta promoters was detected in 12 (27%), 26 (58%), and 24 (53%) of the 45 gastric carcinomas, respectively. Hypermethylation of the p16INK4a promoter was more common in intestinal type than in diffuse type gastric carcinomas (p = 0.0023; Fisher's exact test) and was inversely associated with p53 mutations (p = 0.0225; Fisher's exact test). However, CDH1 and RAR-beta promoter hypermethylation was observed more frequently in diffuse,scattered type gastric carcinoma than in other types (intestinal and diffuse,adherent types) (p = 0.0175 and p = 0.0335, respectively; Fisher's exact test) and was not associated with p53 mutation status. Moreover, hypermethylation of the CDH1 and RAR-beta promoters occurred concordantly (p < 0.0001; Fisher's exact test). These results suggest that at least two types of promoter methylation status are involved in the development of the intestinal (p16INK4a promoter hypermethylation) and diffuse,scattered types (CDH1 and RAR-beta promoter hypermethylation) of gastric carcinoma. Copyright © 2002 John Wiley & Sons, Ltd. [source]


    EGFR mutation testing in NSCLC: Patterns of care and outcomes in Western Australia

    ASIA-PACIFIC JOURNAL OF CLINICAL ONCOLOGY, Issue 1 2009
    Suzanne WEBB
    Abstract Aims: This study evaluated the EGFR mutation status, administration of gefitinib or erlotinib and outcomes of patients assessed for EGFR mutations since the commencement of testing in Western Australia. Methods: A retrospective study identified patients with NSCLC who undergone EGFR mutation testing in the Department of Anatomical Pathology, Royal Perth Hospital, Western Australia from March 2005 until May 2007. Patient characteristics, cancer history, treatment, outcomes and survival were collected from the medical records and pathology reports. Results: Tumor samples from 64 patients were sequenced for mutations in exons 18,21 EGFR and, of these, 53 patients with NSCLC were included in the analysis. The mean age at diagnosis was 61 years (range 19,80) and most of the tumor samples tested were from female patients (76%). Overall 36% of patients tested were mutation-positive with 95% of mutations occurring in exons 19 or 21. A total of 63% of mutation-positive and 18% of mutation-negative patients were treated with gefitinib or erlotinib. Of these, 83% of patients whose tumors had an EGFR mutation had a favorable response following treatment, compared to 17% of mutation-negative patients. The duration of treatment was longer in mutation-positive patients (mean 30 weeks vs 9 weeks). Conclusion: EGFR mutation testing is not routinely performed in NSCLC in Western Australia. Referral for testing is at the discretion of the treating physician, accounting for the high proportion of women and adenocarcinoma histology. Selection of mutation-positive tumors for treatment with gefitinib or erlotinib is associated with good responses to treatment. This study supports the use of gefitinib or erlotinib in routine clinical practice in patients with NSCLC carrying an EGFR mutation. [source]


    Filaggrin null mutations increase the risk and persistence of hand eczema in subjects with atopic dermatitis: results from a general population study

    BRITISH JOURNAL OF DERMATOLOGY, Issue 1 2010
    J.P. Thyssen
    Summary Background, Hand eczema is prevalent in the general population. It remains unclear whether or not filaggrin gene (FLG) null mutations increase the overall risk of hand eczema or only increase the risk of hand eczema in subjects with atopic dermatitis. Objectives, To investigate the association between FLG null mutations and hand eczema. Methods, A random sample of 3335 adults from the general population in Denmark was patch tested, FLG genotyped for R501X and 2282del4 null mutations and questioned about hand eczema. Results, Participants with combined presence of atopic dermatitis and FLG null mutation status had a significantly higher prevalence of hand eczema, an earlier onset of hand eczema and a higher persistence of hand eczema compared with subjects with normal FLG status and absence of atopic dermatitis. Logistic regression analyses revealed positive associations between hand eczema within the past 12 months and FLG null mutation status in participants with a history of atopic dermatitis [odds ratio (OR) 2·98; 95% confidence interval (CI) 1·27,7·01], but not in subjects without atopic dermatitis (OR 0·82; 95% CI 0·41,1·67). Conclusions,FLG null mutations were significantly associated with hand eczema (< 12 months) in subjects with atopic dermatitis. Combined atopic dermatitis and filaggrin null mutation status was strongly associated with early onset of hand eczema and hand eczema persistence. [source]


    Mutant p53 melanoma cell lines respond differently to CP-31398-induced apoptosis

    BRITISH JOURNAL OF DERMATOLOGY, Issue 5 2005
    C.K. Ho
    Summary Background, p53, a commonly mutated gene in human cancers, participates in cell cycle arrest, DNA repair and apoptosis. A small pharmacological compound, CP-31398, was found to have the ability to promote proper p53 protein folding, activate p53 transcription of downstream targets, and slow tumour growth in mice. Additionally, CP-31398 was found to be able to convert mutant p53 to wild-type conformation in several cell lines. Objectives, To examine if CP-31398 can revert all mutant p53 proteins to wild-type function. Methods, We studied a series of apoptotic responses to CP-31398 in three melanoma cell lines varying in p53 mutation status. Results, Upon a moderate dose of CP-31398 treatment (15 µg mL,1), only the wild-type p53 MMRU and the single p53 point mutation MeWo cells exhibited apoptosis. Another melanoma cell line, Sk-mel-110, containing multiple p53 mutations, did not exhibit apoptosis. Although CP-31398 enhanced overall p53 protein level, its ability to promote proper folding of p53 protein was limited to CP-31398-sensitive MMRU and MeWo cells. These sensitive cells showed an increased Bax and PUMA transcription, altered mitochondrial membrane potential, followed by the release of cytochrome c, and cleaved caspase-9 and caspase-3. We also demonstrated that Apaf-1 was not involved in CP-31398-mediated apoptosis. Conclusions, Our results suggest that the ability of CP-31398 to revert mutant p53 proteins to wild-type conformation may be correlated to p53 mutational status. More studies are necessary, to further investigate the effect of CP-31398 on mutant p53 and its potential applications as an anticancer agent. [source]


    Colon cancer screening practices and disclosure after receipt of positive or inconclusive genetic test results for hereditary nonpolyposis colorectal cancer,,§

    CANCER, Issue 18 2009
    Anne L. Ersig PhD
    Abstract BACKGROUND: Patients who receive conclusive genetic test results for hereditary nonpolyposis colorectal cancer (HNPCC) tend to adopt appropriate colorectal cancer screening behaviors and disclose their test results. However, little is known about the disclosure processes or screening behaviors of individuals who receive inconclusive genetic test results. This study compared endoscopy use and disclosure between individuals with positive and inconclusive genetic test results, within a year after results were received. METHODS: Individuals with a personal history of cancer and suspected of having HNPCC participated in genetics education and counseling, underwent HNPCC testing, and received genetic test results (GCT) within a prospective cohort study. Demographic, psychosocial, and behavioral data were obtained from questionnaires and interviews completed before and after GCT. RESULTS: Index cases with inconclusive genetic test results were less likely to screen within 12 months. Index cases who disclosed test results to children within 6 months were more likely to screen within 12 months, controlling for mutation status. Index cases with inconclusive genetic test results were less likely to share results with a healthcare provider within 6 months. Index cases who disclosed genetic test results to healthcare providers within 6 months were more likely to have endoscopy within 12 months. CONCLUSIONS: Genetic test results and disclosure significantly affected colon cancer screening at 12-month follow-up. Interventions to improve adherence to colorectal cancer screening should consider increased education of those receiving inconclusive results and encourage disclosure to healthcare providers and family members. Cancer 2009. Published 2009 by the American Cancer Society. [source]


    Accuracy of the BRCAPRO model among women with bilateral breast cancer

    CANCER, Issue 4 2009
    Kaylene J. Ready MS
    Abstract BACKGROUND: The likelihood of identifying a BRCA mutation was often calculated using the BRCAPRO model. A previous study suggested that this model may overestimate the chance of detecting a BRCA mutation among women diagnosed with bilateral breast cancer. Studies also suggested that few patients with bilateral breast cancer whose age at first diagnosis is >40 years were mutation carriers. The objectives of this study were to determine the accuracy of the BRCAPRO model among women with bilateral breast cancer and to determine whether their mutation status was dependent on their age at first diagnosis. METHODS: A retrospective chart review was performed. Women who were diagnosed with bilateral or unilateral breast cancer and who had undergone comprehensive BRCA1 and BRCA2 genetic testing at M. D. Anderson Cancer Center between 1997 and 2006 were included in the study. RESULTS: For individuals with pre-test carrier probabilities >31%, the proportion of positive tests was significantly lower than predicted by the BRCAPRO model (P < .05). In addition, the carrier rate of BRCA mutations was significantly higher (P = .002, Fisher exact test) in women with bilateral breast cancer whose age at first diagnosis was ,40 years compared with those diagnosed >40 years. CONCLUSIONS: The BRCAPRO model was overestimating the relative contribution bilateral breast cancer had on the likelihood of detecting a BRCA1 or BRCA2 mutation. Bilateral breast cancer did not appear to be a good indicator of mutation status, particularly for women whose age at first diagnosis is >40 years. Cancer 2009. © 2009 American Cancer Society. [source]


    Clinicopathologic features and BRAFV600E mutation analysis in cutaneous metastases from well-differentiated thyroid carcinomas

    CANCER, Issue 10 2007
    Lori A. Erickson MD
    Abstract BACKGROUND Cutaneous metastases from well-differentiated thyroid carcinomas are rare and are usually identified in patients with widely disseminated disease. Occasionally, thyroid carcinomas can present as cutaneous metastases for which the primary site needs to be determined. Papillary thyroid carcinomas (PTCs) commonly have BRAFV600E mutation. A series of 16 cutaneous metastases were analyzed from well-differentiated thyroid carcinomas to learn more about the clinicopathologic features and BRAFV600E mutation status. METHODS Eleven cases of PTC and 5 of follicular thyroid carcinoma (FTC) metastatic to the skin were evaluated. All cutaneous metastases were studied histologically and with thyroglobulin and thyroid transcription factor immunostains. All tumor samples were analyzed for mutations at nucleotide 1799 in exon 15 of the BRAF gene. RESULTS Two patients with FTC presented with cutaneous metastases. Fourteen of 16 patients died of disease and 2 were alive with disease at follow-up. The histologic features of the cutaneous metastases were generally characteristic of the primary tumor; however, 2 of the 11 PTC metastases demonstrated cytoplasmic clearing not typical of classic PTC. BRAFV600E mutation (T1799A) was detected in 5 of 11 cases of PTC and in none of the 5 FTCs. CONCLUSIONS Cutaneous metastases from PTC may show prominent clear cell change requiring differentiation from clear cell hidradenoma, clear cell dermatofibroma, malignant melanoma with prominent clear cell change, and cutaneous metastasis from renal cell carcinoma. BRAFV600E mutation is identified in a subset of cutaneous metastases from PTC. Cutaneous metastases from PTC and FTC are associated with a very poor prognosis. Cancer 2007. © 2007 American Cancer Society. [source]


    Clinical significance of pretreatment serum amphiregulin and transforming growth factor-,, and an epidermal growth factor receptor somatic mutation in patients with advanced non-squamous, non-small cell lung cancer

    CANCER SCIENCE, Issue 11 2008
    Katsuhiro Masago
    Circulating amphiregulin and transforming growth factor-, (TGF-,) have been found to be correlated with an unfavorable response to gefitinib based on the identification of patients with a higher probability of resistance to the drug. However, the association between an epidermal growth factor receptor (EGFR) somatic mutation and the overexpression of its ligands has not been determined. To verify the clinical significance of the two serum markers and EGFR mutation status, we determined serum amphiregulin and TGF-, levels by enzyme-linked immunosorbent assay in 93 patients with advanced non-squamous, non-small cell lung cancer and EGFR somatic mutation status using the peptic nucleic acid-locked nucleic acid clamp method in 46 cases. The relationship between each independent clinicopathological variable and the response to gefitinib therapy was examined. We also evaluated the risk factors associated with prognosis. Fourteen (41.0%) of 34 progressive disease cases were positive for amphiregulin (P = 0.007). Eleven (32.4%) of 34 progressive disease cases were positive for TGF-, (P = 0.005). The median survival time of patients with the EGFR somatic mutation was significantly longer (P = 0.01). The same was true of amphiregulin- (P = 0.046) and TGF-,-negative patients (P < 0.01). In multivariate analysis, serum TGF-, positivity (hazard ratio, 2.558; P = 0.005) and the wild type EGFR gene (hazard ratio, 1.894; P = 0.003) were significant independent prognostic factors. Our study demonstrates that the status of the serum EGFR ligand, in addition to EGFR activating mutation, is a predictive factor for response to gefitinib therapy. (Cancer Sci 2008; 99: 2295,2301) [source]


    Epidermal growth factor receptor mutation, but not sex and smoking, is independently associated with favorable prognosis of gefitinib-treated patients with lung adenocarcinoma

    CANCER SCIENCE, Issue 2 2008
    Shinichi Toyooka
    Epidermal growth factor receptor (EGFR) mutations have been reported as a predictive factor for favorable prognosis of gefitinib-treated patients with lung adenocarcinoma. However, its confounding with sex and smoking makes it unclear whether the EGFR mutation is independently associated with prolonged patient survival. In this study, we analyzed a large-scale database to discriminate the survival impact of EGFR mutations against those of sex and smoking after gefitinib therapy. EGFR mutations in exon19 and exon21 named drug-sensitive EGFR mutations were examined to investigate the impact of EGFR mutation, sex, and smoking status on survival of 362 gefitinib-treated patients with lung adenocarcinoma. Drug-sensitive EGFR mutations were detected in 169 patients (46.7%). The multivariate analysis including EGFR, sex, and smoking status showed that drug-sensitive EGFR mutations were significantly related to longer overall survival (OS) (P < 0.001) and progression-free survival (PFS) (P < 0.001). In addition, we investigated the impact of sex and smoking status according to EGFR mutation status, and the impact of EGFR mutation status according to sex and smoking status on survival. Sex and smoking status were not significantly associated with longer OS and PFS according to EGFR mutation status. Drug-sensitive EGFR mutations were significantly associated with longer OS and PFS according to sex or smoking status. Our results indicated that drug-sensitive EGFR mutations were the only independent factor for longer survival of patients treated with gefitinib, suggesting that patient selection based on EGFR mutation status for gefitinib therapy will lead to a better outcome for patients with lung adenocarcinoma. (Cancer Sci 2008; 99: 303,308) [source]


    Epidermal growth factor receptor mutation status and clinicopathological features of combined small cell carcinoma with adenocarcinoma of the lung

    CANCER SCIENCE, Issue 11 2007
    Tomoya Fukui
    In lung cancer, somatic mutations of epidermal growth factor receptor (EGFR) are concentrated in exons 18,21, especially in adenocarcinoma (Ad), but these mutations have rarely been reported in small cell lung carcinoma (SCLC). Combined SCLC is rare, and the EGFR mutation status and its relationship to the clinicopathological features of this tumor type have not yet been elucidated. We retrospectively studied six patients with combined SCLC with Ad components among 64 consecutive patients who underwent resection of SCLC. The clinicopathological features of each patient were reviewed, especially for the distribution pattern of the Ad component and lymph node metastases. EGFR mutations were screened by high-resolution melting analysis in each case, and were confirmed by sequencing of each mutation in the microdissected SCLC or Ad components. Regarding EGFR, no specific mutation was detected in five of the six patients, whereas one female patient who had never smoked had a missense mutation. In this case, both the SCLC and Ad components shared the same mutation in exon 21 (L858R). We identified a patient with combined SCLC with Ad sharing an identical EGFR mutation in both the SCLC and Ad components. In addition to the clinicopathological characteristics of this rare histological type of lung cancer, these findings provide useful information for better understanding the biology, natural history and clinical management of SCLC. (Cancer Sci 2007; 98: 1714,1719) [source]


    The role of SMAD4 in early-onset colorectal cancer

    COLORECTAL DISEASE, Issue 3 2010
    S. G. Royce
    Abstract Objective, Chromosomal loss within the region of 18q and loss of SMAD4 expression have been reported to be frequent somatic events during colorectal cancer tumour progression; however, their associations with age at onset have not been widely studied. Method, We analysed 109 tumours from a population-based case-family study based on colorectal cancers diagnosed before the age of 45 years. These patients with early-onset colorectal cancer had been previously screened for germ-line mismatch repair gene mutations, microsatellite instability (that included the mononucleotide repeat in TGF,RII) and somatic k-ras mutations. We measured SMAD4 protein expression using immunohistochemistry and SMAD4 copy number using quantitative real-time PCR. Results, Loss of SMAD4 protein expression was observed in 27/109 (25%) of cancers tested and was more commonly observed in rectal tumours (15/41, 36%) when compared with tumours arising in the colon (11/66, 17%) (P = 0.04). There was no association between SMAD4 protein expression and TGF,R11 mutation status, SMAD4 copy number, family history, MSI status, tumour stage or grade. Conclusion, Loss of SMAD4 expression is a common feature of early-onset colorectal tumours as it is in colorectal cancers diagnosed in other age-groups. Taken together, the molecular pathways (genetic and epigenetic) now known to be involved in early-onset colorectal cancer only explain a small proportion of the disease and require further exploration. [source]