Epithelial dysplasia of gall bladder is an important precancerous lesion of gall bladder carcinogenesis. To investigate the frequency of K-ras gene mutation in gall bladder carcinoma and dysplasia, K-ras codon 12 mutations were investigated by the polymerase chain reaction/restriction enzyme based method following direct sequencing. Mutation was detected in 59% (30 of 51) of gall bladder carcinomas, in 73% (8 of 11) of gall bladder dysplasia in gall stone cases, and in 0% of the normal gall bladder epithelium. There was, however, no correlation between K-ras mutation and clinicopathological factors of gall bladder carcinoma. K-ras gene mutation occurs even in gall bladder dysplasia at an incidence similar to that in carcinomas, suggesting that testing for K-ras gene mutation may prove useful as an adjunct to bile cytological or biopsy analysis.
The colorectal cancer paradigm explains how genetic and histological changes lead normal epithelial cell to transform into pre-malignant adenomas then progress to malignant carcinomas. Using the Genetic Alterations in Cancer Knowledge System intragenic allele loss and gene mutation data from approximately 9000 colorectal tumors were compared to the model of colorectal tumor development. The distribution of mutations along the TP53 codons as a function of tumorigenesis also was analyzed. Alterations of APC, KRAS and TP53 were observed in a higher percentage of adenocarcinomas compared to adenomas (P<0.05) indicating that the alterations accumulated with malignancy. Alterations in BRAF, CTNNB, HRAS and NRAS were infrequent regardless of morphology. Differences were observed in the distribution of TP53 mutations with tumorigenesis. Mutations (single base substitutions) occurred most frequently at codons 175 and 273 in both tumor types; however, in adenocarcinomas the mutation incidence at codon 248 was approximately three times that reported in adenomas. It is proposed that the higher incidence of mutation at codon 248 is a later event in colorectal tumorigenesis that occurs as the tumors become malignant.
Bladder carcinoma, which has the ninth highest incidence among malignant tumors in the world, is a complex, multifactorial disease. The malignant transformation of bladder cells results from DNA mutations and alterations in gene expression levels. In this work, we used a bioinformatics approach to investigate the molecular mechanisms of bladder carcinoma. Biochips downloaded from the Gene Expression Omnibus (GEO) were used to analyze the gene expression profile in urinary bladder cells from individuals with carcinoma. The gene expression profile of normal genomes was used as a control. The analysis of gene expression revealed important alterations in genes involved in biological processes and metabolic pathways. We also identified some small molecules capable of reversing the altered gene expression in bladder carcinoma; these molecules could provide a basis for future therapies for the treatment of this disease.
Bladder carcinoma; differential expression; expression profile; small molecular mimic; susceptibility forecast
The diagnosis and follow-up of patients with bladder cancer rely on invasive procedures (cystoscopy with biopsy). Polymerase chain reaction (PCR)-based technologies may allow the sensitive detection of cancer-related genetic mutations in exfoliated tumour material, potentially allowing the development of less invasive techniques. This pilot study investigated the feasibility of detecting mutations in exons 5–8 of the p53 gene using single-stranded conformational polymorphism (SSCP) analysis in bladder-washing specimens from patients with bladder cancer. Bladder-washing samples (31) were collected from patients (27) with bladder cancer. An abnormal additional SSCP band was detected in five samples from five different patients suggesting the presence of a p53 mutation. In all five cases the same abnormal SSCP pattern was demonstrated in samples of the corresponding bladder tumour. In one case bladder washings were available from the same patient on two separate occasions with one washing demonstrating a mutation and the other not. In two further cases a mutation was demonstrated in the bladder tumour but not in the corresponding washing. It is concluded that it is possible to detect and characterize p53 mutations in bladder-washing samples from patients with bladder cancer. Improved sensitivity in detecting mutations in a sample containing a mixture of normal and malignant cells may lead to the clinical applicability of molecular methods of disease monitoring. © 2000 Cancer Research Campaign
p53; mutations; bladder cancer; bladder washings
Although Iraqis sustained the gravest exposure conditions during the 1991 Gulf War (GW), little is known about the possible relationship between environmental exposures during the GW and long-term health in Iraqis.
To study the relationship between distance from Kuwait during the GW and somatic health among Iraqi Soldiers vs civilians.
A survey questionnaire was distributed to a sample of 742 GW veterans and 413 civilians in Iraq. The odds ratios were calculated for somatic disorders as a function of distance from Kuwait during the GW, as well as a self-reported environmental exposure index.
Soldiers reported a significantly higher prevalence of somatic disorders as compared to civilians. Soldiers closest to Kuwait reported significantly more somatic disorders as compared to Soldiers deployed further away from Kuwait.
Iraqi GW veterans are at an increased risk of numerous somatic disorders. Soldiers are at an increased risk compared to civilians, suggesting that war-associated exposures are of etiologic relevance.
Analysis of human tumour-derived cell lines has previously resulted in the identification of novel transformation-related elements and provided a useful tool for functional studies of different genes. To establish the utility of such cell lines as indicators of change relevant to urothelial cancer, we have characterised the expression of five genes (p53, MDM2, Rb, E-cadherin, APC) within a panel of human bladder carcinoma cell lines. Using single-strand conformation polymorphism (SSCP) and direct sequencing, p53 mutations were identified in 7/15 (47%) cell lines reflecting events reported in bladder tumours. Immunohistochemical analysis of p53 in cultured cells and in paraffin-embedded sections of xenografts from the cell line panel revealed discordant results. An absence of p53 nuclear staining was associated with an exon 5 mutation in EJ and with multiple p53 mutations found in J82. Two cell lines positive for p53 staining in the absence of detectable mutation displayed overexpression of MDM2 (PSI, HT1197) in Western blot analysis. Loss or aberrant Rb expression was recorded in 5/15 (TCCSUP, SCaBER, 5637, HT1376, J82) cell lines. Absence of E-cadherin was recorded in 5/15 cell lines (TCCSUP, EJ, KK47, UM-UC-3, J82) with loss of alpha-catenin in immunoprecipitated E-cadherin complexes of CUBIII. Western blot analysis of APC revealed a truncated protein in 1/15 (CUBIII) cell lines. The characterisation of oncogenic events within this panel of human bladder carcinoma cell lines establishes a representation of change observed in bladder tumours and better defines the genotypic background in these experimental human cell models of neoplastic progression.
Growing evidence indicates that Rab GTPases, key regulators of intracellular transport in eukaryotic cells, play an important role in cancer. We analysed the deregulation at the transcriptional level of the genes encoding Rab proteins and Rab-interacting proteins in bladder cancer pathogenesis, distinguishing between the two main progression pathways so far identified in bladder cancer: the Ta pathway characterized by a high frequency of FGFR3 mutation and the carcinoma in situ pathway where no or infrequent FGFR3 mutations have been identified. A systematic literature search identified 61 genes encoding Rab proteins and 223 genes encoding Rab-interacting proteins. Transcriptomic data were obtained for normal urothelium samples and for two independent bladder cancer data sets corresponding to 152 and 75 tumors. Gene deregulation was analysed with the SAM (significant analysis of microarray) test or the binomial test. Overall, 30 genes were down-regulated, and 13 were up-regulated in the tumor samples. Five of these deregulated genes (LEPRE1, MICAL2, RAB23, STXBP1, SYTL1) were specifically deregulated in FGFR3-non-mutated muscle-invasive tumors. No gene encoding a Rab or Rab-interacting protein was found to be specifically deregulated in FGFR3-mutated tumors. Cluster analysis showed that the RAB27 gene cluster (comprising the genes encoding RAB27 and its interacting partners) was deregulated and that this deregulation was associated with both pathways of bladder cancer pathogenesis. Finally, we found that the expression of KIF20A and ZWINT was associated with that of proliferation markers and that the expression of MLPH, MYO5B, RAB11A, RAB11FIP1, RAB20 and SYTL2 was associated with that of urothelial cell differentiation markers. This systematic analysis of Rab and Rab effector gene deregulation in bladder cancer, taking relevant tumor subgroups into account, provides insight into the possible roles of Rab proteins and their effectors in bladder cancer pathogenesis. This approach is applicable to other group of genes and types of cancer.
The population military veterans attending college is rapidly growing as veterans return from Operations Enduring Freedom and Iraqi Freedom (OEF/OIF). We sought to describe patterns of student veterans’ health-related behaviors and how they might differ from their non-veteran peers.
We analyzed data from the 2008 Boynton College Student Health Survey (CSHS).
CSHS participants completed an anonymous online survey.
The CSHS sampled students (n=8,651) attending public, private, two-, and four-year postsecondary educational institutions in Minnesota.
The CSHS included items on substance use (including alcohol and tobacco), safety, nutrition, and physical activity.
We described demographics of OEF/OIF veteran, non-OEF/OIF veteran, and non-veteran students and used poisson regression to compute adjusted relative risks (ARR) with 95% confidence intervals to characterize associations between veteran status and health behaviors.
After controlling for demographics, veteran students reported more safety-, tobacco-, and alcohol-related risk behaviors compared to non-veteran students. For instance, compared to the non-veteran reference group, the ARR for past year smokeless tobacco use and physical fighting among for OEF/OIF veterans was 1.76 [CI: 1.31–2.35] and 1.48 [CI: 1.22–1.79] respectively. Veteran and non-veteran students display similar weight-related behaviors, though OEF/OIF veteran students were more likely to engage in strengthening exercises.
There are specific health risk behaviors which are particularly relevant for veterans attending postsecondary institutions. As veterans enroll in postsecondary education there is a unique window of opportunity for health promotion in this population.
Veterans; Young Adult; Tobacco; Substance Abuse; Obesity; Safety
Evidence is accumulating that the tumour-suppressor gene p53 is involved in the development of bladder cancer. Therefore we studied p53 mutations in 47 bladder cancers obtained from 45 patients using polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) analysis. Eight out of 24 invasive tumours appeared to have a p53 mutation, while no p53 mutations were found in the superficial tumours. All the p53 mutations were found in grade 3 tumours. The tumours with altered p53 showed a higher frequency of allelic loss (FAL) than the tumours without a mutation (55.8% vs 21.1%, P < 0.05, chi 2 test). This increase in FAL suggests a correlation between p53 mutations and genetic instability. A significant correlation between mutated p53 and poor survival in the whole group studied was found (P < 0.001, log-rank test). However, within the group of muscle-invasive tumours the occurrence of p53 mutations had no additional prognostic value. Therefore, even though p53 mutations were found in aggressive tumours, the clinical usefulness of its detection seems limited. Nevertheless, these results imply that p53 is involved in the clinical behaviour of bladder cancer; its role in the progression of superficial cancer to invasive disease merits further attention.
Inactivation of the retinoblastoma (RB) gene is known to be implicated in the pathogenesis of several types of human cancers. Since structural alterations of the RB gene have not been well examined in human bladder cancer, we looked for mutations in the entire coding region of this gene using polymerase chain reaction (PCR) and single-strand conformational polymorphism analysis of RNA. We also examined allelic loss of the RB gene using PCR-based restriction fragment length polymorphism analysis. Of 30 samples obtained from patients with bladder cancer, eight (27%) were found to have RB gene mutations. DNA sequencing of the PCR products revealed five cases with single point mutations and three cases with small deletions. These mutations included one (10%) of ten low-grade (grade 1) tumours, four (50%) of eight intermediate-grade (grade 2) tumours and three (25%) of 12 high-grade (grade 3) tumours. Likewise, mutations were found in four (21%) of 19 superficial (pTa and pT1) tumours and four (36%) of 11 invasive (pT2 or greater) tumours. In 15 informative cases, loss of heterozygosity at the RB locus was shown in five cases (33%), three cases with RB mutations and two without them. These results suggest that RB gene mutations are involved in low-grade and superficial bladder cancers as well as in high-grade and invasive cancers.
Epigenetic alterations are a hallmark of human cancer. In this study, we aimed to investigate whether aberrant DNA methylation of cancer-associated genes is related to urinary bladder cancer recurrence.
A set of 4 genes, including CDH1 (E-cadherin), SFN (stratifin), RARB (retinoic acid receptor, beta) and RASSF1A (Ras association (RalGDS/AF-6) domain family 1), had their methylation patterns evaluated by MSP (Methylation-Specific Polymerase Chain Reaction) analysis in 49 fresh urinary bladder carcinoma tissues (including 14 cases paired with adjacent normal bladder epithelium, 3 squamous cell carcinomas and 2 adenocarcinomas) and 24 cell sediment samples from bladder washings of patients classified as cancer-free by cytological analysis (control group). A third set of samples included 39 archived tumor fragments and 23 matched washouts from 20 urinary bladder cancer patients in post-surgical monitoring. After genomic DNA isolation and sodium bisulfite modification, methylation patterns were determined and correlated with standard clinic-histopathological parameters.
CDH1 and SFN genes were methylated at high frequencies in bladder cancer as well as in paired normal adjacent tissue and exfoliated cells from cancer-free patients. Although no statistically significant differences were found between RARB and RASSF1A methylation and the clinical and histopathological parameters in bladder cancer, a sensitivity of 95% and a specificity of 71% were observed for RARB methylation (Fisher's Exact test (p < 0.0001; OR = 48.89) and, 58% and 17% (p < 0.05; OR = 0.29) for RASSF1A gene, respectively, in relation to the control group.
Indistinct DNA hypermethylation of CDH1 and SFN genes between tumoral and normal urinary bladder samples suggests that these epigenetic features are not suitable biomarkers for urinary bladder cancer. However, RARB and RASSF1A gene methylation appears to be an initial event in urinary bladder carcinogenesis and should be considered as defining a panel of differentially methylated genes in this neoplasia in order to maximize the diagnostic coverage of epigenetic markers, especially in studies aiming at early recurrence detection.
The fibroblast growth factor receptor 3 (FGFR3) gene is known to be frequently mutated in noninvasive urothelial carcinomas of the bladder. In this study, we investigated the expression of FGFR3, Ki-67, and p53 in bladder cancers and the effects of expression on tumor recurrence.
Materials and Methods
Fifty-five cases of primary bladder cancer were examined by immunohistochemistry. The relationship of these markers with various clinicopathological factors, including recurrence, was assessed.
Positivity for cytoplasmic FGFR3 (FGFR3-c) was associated with a lower cancer grade (p=0.022) and stage (p=0.011). Recurrence was more frequent in patients with a higher stage, negative FGFR3-c, and high Ki-67 expression. According to univariate analysis, predictors of recurrence-free survival included the following: age, stage, FGFR-c, Ki-67, and p53. However, none of these was independent from the other parameters in multivariate studies.
The immunohistochemical expression of FGFR3 is not only one of the characteristic features of lower-grade and lower-stage urothelial carcinoma but also a possible marker in predicting disease recurrence.
Carcinoma, transitional cell; Fibroblast growth factor receptor 3; p53 genes; Recurrence
To discover whether post-combat syndromes have existed after modern wars and what relation they bear to each other.
Review of medical and military records of servicemen and cluster analysis of symptoms.
Records for 1856 veterans randomly selected from war pension files awarded from 1872 and from the Medical Assessment Programme for Gulf war veterans.
Main outcome measures
Characteristic patterns of symptom clusters and their relation to dependent variables including war, diagnosis, predisposing physical illness, and exposure to combat; and servicemen's changing attributions for post-combat disorders.
Three varieties of post-combat disorder were identified—a debility syndrome (associated with the 19th and early 20th centuries), somatic syndrome (related primarily to the first world war), and a neuropsychiatric syndrome (associated with the second world war and the Gulf conflict). The era in which the war occurred was overwhelmingly the best predictor of cluster membership.
All modern wars have been associated with a syndrome characterised by unexplained medical symptoms. The form that these assume, the terms used to describe them, and the explanations offered by servicemen and doctors seem to be influenced by advances in medical science, changes in the nature of warfare, and underlying cultural forces.
What is already known on this topicService in the Gulf war is associated with an increased rate of reported symptoms and worsening subjective healthPost-combat syndromes have been described after most modern conflicts from the US civil war onwardsWhat this study addsThere seems to be no single post-combat syndrome but a number of variations on a themeThe ever changing form of post-combat syndromes seems to be related to advances in medical understanding, the developing nature of warfare, and cultural undercurrentsBecause reported symptoms are subject to bias and changing emphasis related to advances in medical science or the discovery of new diseases, the characterisation of individual syndromes has to be treated with cautionAttributions by servicemen are generally consistent with symptom characteristics, though there seems to be a growing reluctance to consider the stress of military service as a cause
The activation of the cHa-ras oncogene in the EJ/T24 bladder carcinoma cell line was compared with the activation of the same gene in the rat-derived Harvey murine sarcoma virus. The results indicate that, like the human oncogene, the Harvey murine sarcoma virus-borne ras gene owes its oncogenic capacity to point mutations in coding sequences rather than to the alteration in transcriptional control that occurred when the formerly cellular ras sequences were acquired by the virus. The viral gene retained its transforming ability when its transcription was removed from the influence of the retroviral long terminal repeat promoter and was placed under the regulation of the cHa-ras promoter. Conversely, the viral long terminal repeat was insufficient to activate the normal cHa-ras allele when a single copy of such a construct was delivered to a cell by viral infection. In addition to their mode of activation, the biological properties of the EJ/T24 and Harvey murine sarcoma virus oncogenes were compared by infecting newborn mice with chimeric retroviruses bearing each form. The two alleles acted equivalently, causing erythroleukemias and sarcomas with similar kinetics.
Chemicals from occupational exposure and components of cigarette smoke can cause DNA damage in bladder urothelium. Failure to repair DNA damage by DNA repair proteins may result in mutations leading to genetic instability and the development of bladder cancer. Immunohistochemistry studies have shown DNA damage signal activation in precancerous bladder lesions which is lost on progression, suggesting that the damage signalling mechanism acts as a brake to further tumorigenesis. Single nucleotide polymorphisms (SNPs) in DSB signalling genes may alter protein function. We hypothesized that SNPs in DSB signalling genes may modulate predisposition to bladder cancer and influence the effects of environmental exposures.
We recruited 771 cases and 800 controls (573 hospital-based and 227 population-based from a previous case-control study) and interviewed them regarding their smoking habits and occupational history. DNA was extracted from a peripheral blood sample and genotyping of 24 SNPs in MRE11, NBS1, RAD50, H2AX and ATM was undertaken using an allelic discrimination method (Taqman).
Smoking and occupational dye exposure were strongly associated with bladder cancer risk. Using logistic regression adjusting for age, sex, smoking and occupational dye exposure, there was a marginal increase in risk of bladder cancer for an MRE11 3'UTR SNP (rs2155209, adjusted odds ratio 1.54 95% CI (1.13–2.08, p = 0.01) for individuals homozygous for the rare allele compared to those carrying the common homozygous or heterozygous genotype). However, in the hospital-based controls, the genotype distribution for this SNP deviated from Hardy-Weinberg equilibrium. None of the other SNPs showed an association with bladder cancer and we did not find any significant interaction between any of these polymorphisms and exposure to smoking or dye exposure.
Apart from a possible effect for one MRE11 3'UTR SNP, our study does not support the hypothesis that SNPs in DSB signaling genes modulate predisposition to bladder cancer.
Colorectal, endometrial and upper urinary tract tumours are characteristic for Lynch syndrome (hereditary non-polyposis colon carcinoma, HNPCC). The aim of the present study was to establish whether carriers of mutations in mismatch repair genes MLH1, MSH2 or MSH6 are at increased risk of urinary bladder cancer.
Carriers and first degree relatives of 95 families with a germline mutation in the MLH1 (n=26), MSH2 (n=43), or MSH6 (n=26) gene were systematically questioned about the occurrence of carcinoma. The cumulative risk of cancer occurring before the age of 70 years (CR70) was compared to the CR70 of the general Dutch population. Microsatellite instability (MSI) testing and/or immunohistochemistry (IHC) for mismatch repair proteins was performed on bladder tumour tissue.
Bladder cancer was diagnosed in 21 patients (90% men) from 19 Lynch syndrome families (2 MLH1, 15 MSH2, and 4 MSH6). CR70 for bladder cancer was 7.5% (95% CI 3.1% to 11.9%) for men and 1.0% (95% CI 0% to 2.4%) for women, resulting in relative risks for mutation carriers and first degree relatives of 4.2 (95% CI 2.2 to 7.2) for men and 2.2 (95% CI 0.3 to 8.0) for women. Men carrying an MSH2 mutation and their first degree relatives were at highest risks: CR70 for bladder and upper urinary tract cancer being 12.3% (95% CI 4.3% to 20.3%) and 5.9% (95% CI 0.7% to 11.1%). Bladder cancer tissue was MSI positive in 6/7 tumours and loss of IHC staining was found in 14/17 tumours, indicating Lynch syndrome aetiology.
Patients with Lynch syndrome carrying an MSH2 mutation are at increased risk of urinary tract cancer including bladder cancer. In these cases surveillance should be considered.
Lynch syndrome; HNPCC; urothelial cancer; bladder cancer; MSI; gastroenterology; clinical genetics; genetic screening/counselling; cancer: urological
The frequency of point mutations at codons 12 and 13 of the c-K-ras gene has been determined in a panel of more than 400 human tumors. Mutant c-K-ras genes were detected in about 75% of adenocarcinomas of the pancreas (n = 84); 40% of adenomas (n = 72) and carcinomas (n = 244) of the colon end rectum; 30% of carcinomas of the bile duct (n = 19); 25% of carcinomas of the lung (n = 92), and in lower frequency in other carcinomas, including liver, stomach, and kidney. No mutations were found in carcinomas of the breast, prostate, esophagus, and gall bladder, among others. Comparative analysis of the spectrum of mutations show that while G to A transitions were the most frequent mutations in pancreatic and colo-rectal tumors, G to T transversions were more prevalent in lung carcinomas. The aspartic acid mutation at codon 13 (GGC----GAC) was relatively frequent in colo-rectal tumors but rare in pancreatic and lung carcinomas. The differences in the mutation spectrum of the c-K-ras gene in cancers of the gastrointestinal and respiratory tracts are suggestive of differential exposure to genotoxic agents.
The aromatic amine 4-aminobiphenyl (4-ABP) is an environmental and occupational contaminant known to be a major etiological agent of human bladder cancer. 4-ABP metabolites are able to form DNA adducts that may induce mutations and initiate bladder carcinogenesis. Cells exposed to 4-ABP may develop resistance to the carcinogen. The aim of the present study was to detect and identify proteins whose expression is altered in the bladder carcinoma RT112 sub-lines selected for acquired resistance to 4-ABP, in order to disentangle the mechanisms.
Differential proteome analysis of cell lysates showed an overall perturbation in cell metabolism and energy pathways in the 4-ABP-resistant human urothelial clones, with over-expression of membrane trafficking proteins such as annexin 2. The resistant clones had altered expression of many proteins linked directly (i.e. lamin A/C, programmed cell death 6 interacting protein) or indirectly (i.e. 94 kDa glucose-regulated protein, fatty acid-binding protein) to decreased apoptosis, suggesting that resistance to 4-ABP might be associated with low apoptotic activity.
Our data provide evidence that deregulation of apoptosis and membrane trafficking proteins might be strongly implicated in the selection of carcinogen resistant cells. Some of these proteins might have potential as biomarkers of resistance and cancer risk.
Perivascular epithelioid cell neoplasms (PEComas) of the urinary bladder are extremely rare and the published cases were comprised predominantly of middle-aged patients. Herein, the authors present the first urinary bladder PEComa occurring in an adolescent. This 16-year-old Chinese girl present with a 3-year history of abdominal discomfort and a solid mass was documented in the urinary bladder by ultrasonography. Two years later, at the age of 18, the patient underwent transurethral resection of the bladder tumor. Microscopically, the tumor was composed of spindled cells mixed with epithelioid cells. Immunohistochemically, the tumor were strongly positive for HMB45, smooth muscle actin, muscle-specific actin, and H-caldesmon. Fluorescence in situ hybridization analysis revealed no evidence of EWSR1 gene rearrangement. The patient had been in a good status without evidence of recurrence 13 months after surgery. Urinary bladder PEComa is an extremely rare neoplasm and seems occur predominantly in middle-aged patients. However, this peculiar lesion can develop in pediatric population and therefore it should be rigorously distinguished from their mimickers.
The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1870004378817301
Perivascular epithelioid cell neoplasms; Urinary bladder; Adolescent
The aim of this study was to analyze the distribution of FGFR3 mutations in bladder tumors of different grade and stage and determine the relation of mutations to chromosomal alterations detected by comparative genomic hybridization (CGH). One hundred bladder cancer samples served as templates for manual microdissection. DNA was isolated from dissected samples containing at least 80% tumor cells. Mutations in FGFR3 were analyzed by SNaPshot analysis. CGH was carried out according to standard protocols. FGFR3 mutations were detected in 45 of 92 samples (48.9%). Concerning T-category, the following mutation frequencies occurred: pTa, 69%; pT1, 38%; and pT2-3, 0%. The mutation frequency was significantly associated with tumor grade: G1, 72%; G2, 56%; and G3, 4%. In pTaG1 tumors, mutations were found in 74%. A significantly lower number of genetic alterations per tumor detected by CGH was associated with FGFR3 mutations (2 vs 8). This association was also seen in pTaG1 tumors: 2.5 (with mutation) vs 7.5 (without mutation). FGFR3 mutations characterize noninvasive low-risk tumors of low malignancy. The low malignant potential of these tumors is underlined by a low number of genetic alterations per tumor. Therefore, FGFR3 represents a valuable prognostic marker of tumors with low malignant potential and can be used as surrogate marker for the detection of genetically stable bladder tumors.
Mutations in the TP53 gene are the most common alterations in human tumours. TP53 mutational patterns have sometimes been linked to carcinogen exposure. In hepatocellular carcinoma, a specific G>T transversion on codon 249 is classically described as a fingerprint of aflatoxin B1 exposure. Likewise G>T transversions in codons 157 and 158 have been related to tobacco exposure in human lung cancers. However, controversies remain about the interpretation of TP53 mutational pattern in tumours as the fingerprint of genotoxin exposure. By using a functional assay, the Functional Analysis of Separated Alleles in Yeast (FASAY), the present study depicts the mutational pattern of TP53 in normal human fibroblasts after in vitro exposure to well-known carcinogens: benzo[a]pyrene, aflatoxin B1 and acetaldehyde. These in vitro patterns of mutations were then compared to those found in human tumours by using the IARC database of TP53 mutations. The results show that the TP53 mutational patterns found in human tumours can be only partly ascribed to genotoxin exposure. A complex interplay between the functional impact of the mutations on p53 phenotype and the cancer natural history may affect these patterns. However, our results strongly support that genotoxins exposure plays a major role in the aetiology of the considered cancers.
Environmental health concerns in the Persian Gulf are peculiar to the geography of the region. Prevention of heat and solar injury deserves primary consideration, but cold injury also may occur in the desert. Immunizations are recommended against a number of diseases, while malarial chemoprophylaxis is necessary in Iraq and Kuwait. In addition to malaria, other parasitic diseases deserve consideration. Diarrheal diseases, diseases from the desert dust, and products of infected desert animals are of concern. Additional natural hazards are venomous bites from scorpions and desert snakes. Finally, threats of enemy action necessitated protection from nuclear biological and chemical weapons and LASER eye/skin injury. Unexploded ordinance will constitute a continuing hazard into the future.
The tumor suppressor gene, PTEN, has previously been demonstrated to be involved in breast tumorigenesis and tumor progression. The aim of the present study was to investigate the expression and significance of PTEN in breast carcinomas, to detect the mutation frequency of PTEN in sporadic breast carcinoma tissues and to determine the association between PTEN promoter methylation and gene expression. Immunohistochemical methods were used to analyze the expression of the PTEN gene in 146 cases of breast carcinoma and 10 cases of normal breast tissue closely adjacent to the carcinoma. Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis was used to analyze conformation polymorphisms in 45 breast carcinoma and 10 normal breast tissues. Point mutations of abnormal single stranded conformation were detected by DNA sequencing. The methylation of the PTEN promoter was analyzed by methylation-specific PCR. Expression of PTEN was detected in 57.5% (84/146) of patients with breast carcinoma. By contrast, PTEN expression was detected in 100% of normal samples. Expression of PTEN was found to negatively correlate with the tumor size, the pathological stage and the expression of the estrogen receptor (ER) and the progesterone receptor (PR) in breast cancer. The 2-year disease-free survival of patients with a high expression of PTEN was higher compared with those with low PTEN expression (P<0.05). Missense mutations in exon 2 of PTEN were identified in 1/45 breast cancer cases. PTEN promoter methylation was detected in 31.1% (14/45) of breast carcinomas, of which 64.3% (9/14) were associated with a loss of PTEN expression. The tumor suppressor gene, PTEN, was abnormally expressed in the breast carcinomas. The number of PTEN mutations were low (1/45) in the sporadic breast cancer cases analyzed in the present study and PTEN promoter methylation may have been the main mechanism leading to the decreased expression of PTEN. These results indicate that PTEN is important for the tumorigenesis, development and prognosis of breast cancer.
PTEN gene; breast cancer; gene mutation; promoter methylation
In February, 2007, the Associated Press (AP) conducted a poll of 1,002 adults in the United States about their attitudes towards the war in Iraq. Respondents were remarkably accurate estimating the current death toll of US soldiers, yet were grossly inaccurate in estimating the current death toll of Iraqi civilians. We conducted a search of newspapers reports to determine the extent of the discrepancy between reporting Coalition and Iraqi civilian deaths, hypothesizing that there would be an over-representation of Coalition deaths compared to Iraqi civilian deaths.
We examined 11 U.S. newspapers and 5 non-U.S. newspapers using electronic databases or newspaper web-archives, to record any reports between March 2003 and March 2008 of Coalition and Iraqi deaths that included a numeric indicator. Reports were described as "events" where they described a specific occurrence involving fatalities and "tallies" when they mentioned the number of deaths over a period of time. We recorded the number of events and tallies related to Coalition deaths, Iraqi civilian deaths, and Iraqi combatant deaths
U.S. newspapers report more events and tallies related to Coalition deaths than Iraqi civilian deaths, although there are substantially different proportions amongst the different U.S. newspapers. In four of the five non-US newspapers, the pattern was reversed.
This difference in reporting trends may partly explain the discrepancy in how well people are informed about U.S. and Iraqi civilian fatalities in Iraq. Furthermore, this calls into question the role of the media in reporting and sustaining armed conflict, and the extent to which newspaper and other media reports can be used as data to assess fatalities or trends in the time of war.
In Iraq, the time-consuming, phenotypic drug susceptibility testing (DST) on agar is the sole method available for detecting drug resistance in Myobacterium tuberculosis (TB). Furthermore, only single laboratory across Iraq is performing it on wide scale.
To explore utility of rapid, polymerase chain reaction (PCR)-based systems in detection of drug resistance in under the Iraqi settings.
Settings and Design:
Cross-sectional study. A total of 79 nonduplicated isolates were included in this study. Multiplex allele-specific PCR was used to detect mutations at positions 531, 526, and 516 of the rpoB gene. Two simplex PCR systems were used to detect mutations in katG3 15 gene and inhAP-15.
Statistical Analysis Used:
Chi-square and crosstabs by SPSS v. 20.
On DST, out of 69 isolates, 55 isolates were found multidrug-resistant (MDR)-TB; six isolates were susceptible to both rifampin (RIF) and isoniazid (INH); two isolates were resistant to RIF but not to INH; and six isolates were resistant to INH but not RIF. RIF and INH resistance mutations were detected in 50 (90.9%), and 43 (78.2%) MDR cases, respectively. Combine resistance mutations to RIF and INH were detected in 40 MDR cases (72.7%). The most frequently mutated codon was the codon 531 in rpoB gene, mutated in 42 isolates. inhAP-15 and katG315 codons were found mutated in 23 and 25 MDR cases (54.8% and 58.1%), respectively. Among 57 RIF-resistant isolates, 52 (91.2%) were harboring mutations resistance to RIF.
These PCR-based methods are potential diagnostic and/or screening tools to detect drug-resistance TB in Iraqi settings.
Drug resistance; isoniazid; multidrug-resistant; mutations; polymerase chain reaction; rifampin; tuberculosis