DNA copy number loss and allelic imbalance at 2p16 in lung cancer associated with asbestos exposure.

Five to seven percent of lung tumours are estimated to occur because of occupational asbestos exposure. Using cDNA microarrays, we have earlier detected asbestos exposure-related genomic regions in lung cancer. The region at 2p was one of those that differed most between asbestos-exposed and non-exposed patients. Now, we evaluated genomic alterations at 2p22.1-p16.1 as a possible marker for asbestos exposure. Lung tumours from 205 patients with pulmonary asbestos fibre counts from 0 to 570 million fibres per gram of dry lung, were studied by fluorescence in situ hybridisation (FISH) for DNA copy number alterations (CNA). The prevalence of loss at 2p16, shown by three different FISH probes, was significantly increased in lung tumours of asbestos-exposed patients compared with non-exposed (P=0.05). In addition, a low copy number loss at 2p16 associated significantly with high-level asbestos exposure (P=0.02). Furthermore, 27 of the tumours were studied for allelic imbalances (AI) at 2p22.1-p16.1 using 14 microsatellite markers and also AI at 2p16 was related to asbestos exposure (P=0.003). Our results suggest that alterations at 2p16 combined with other markers could be useful in diagnosing asbestos-related lung cancer.

Gene copy number analysis in malignant pleural mesothelioma using oligonucleotide array CGH.

Conventional cytogenetic analyses and comparative genomic hybridization have revealed a complex and even chaotic nature of chromosomal aberrations in pleural malignant mesothelioma (MM). We set out to describe the complex gene copy number changes and screen for novel genetic aberrations using a high-density oligonucleotide microarray platform for comparative genomic hybridization (aCGH) of a series of 26 well-characterized MM tumor samples. The number of copy number changes varied from zero to 40 per sample. Gene copy number losses predominated over gains, and the most frequent region of loss was 9p21.3 (17/26 cases), the locus of CDKN2A and CDKN2B, both known to be commonly lost in MM. The most recurrent minimal regions of losses were 1p31.1--> p13.2, 3p22.1-->p14.2, 6q22.1, 9p21.3, 13cen-->q14.12, 14q22.1-->qter, and 22qcen-->q12.3. Previously unreported gains included 9p13.3, 7p22.3-->p22.2, 12q13.3, and 17q21.32-->qter. The results suggest that gene copy number losses are a major mechanism of MM carcinogenesis and reveal a recurrent pattern of copy number changes in MM.

Interaction between 5-HT1A and BDNF genotypes increases the risk of treatment-resistant depression.

Several studies have linked 5-HT1A C1019G and BDNF G196A (Val66Met) gene polymorphisms to major depressive disorder (MDD) and the actions of antidepressants. We attempt to show that the interaction between 5-HT1A and BDNF polymorphism predicts the risk of treatment-resistant depression. The sample consists of 119 patients with treatment-resistant MDD and 392 controls. 5-HT1A C1019G and BDNF G196A (Val66Met) polymorphisms were studied. The combination of 5-HT1A GG and BDNF GA + AA genotypes is associated with an increased risk of depression.

Gene expression and copy number profiling suggests the importance of allelic imbalance in 19p in asbestos-associated lung cancer.

Asbestos is a pulmonary carcinogen known to give rise to DNA and chromosomal damage, but the exact carcinogenic mechanisms are still largely unknown. In this study, gene expression arrays were performed on lung tumor samples from 14 heavily asbestos-exposed and 14 non-exposed patients matched for other characteristics. Using a two-step statistical analysis, 47 genes were revealed that could differentiate the tumors of asbestos-exposed from those of non-exposed patients. To identify asbestos-associated regions with DNA copy number and expressional changes, the gene expression data were combined with comparative genomic hybridization microarray data. As a result, a combinatory profile of DNA copy number aberrations and expressional changes significantly associated with asbestos exposure was obtained. Asbestos-related areas were detected in 2p21-p16.3, 3p21.31, 5q35.2-q35.3, 16p13.3, 19p13.3-p13.1 and 22q12.3-q13.1. The most prominent of these, 19p13, was further characterized by microsatellite analysis in 62 patients for the differences in allelic imbalance (AI) between the two groups of lung tumors. 79% of the exposed and 45% of the non-exposed patients (P=0.008) were found to be carriers of AI in their lung tumors. In the exposed group, AI in 19p was prevalent regardless of the histological tumor type. In adenocarcinomas, AI in 19p appeared to occur independently of the asbestos exposure.

Interaction between TPH1 and GNB3 genotypes and electroconvulsive therapy in major depression.

We studied the association between tryptophan hydroxylase 1 (TPH1) A218C and G-protein beta-3 subunit (GNB3) C825T polymorphisms and treatment response in electroconvulsive therapy (ECT). The sample consisted of 119 patients with major depressive disorder (MDD) and 398 controls. Neither TPH1 nor GNB3 polymorphisms are associated with treatment response. However, subjects carrying TPH1 CC genotype are more likely to belong to the patient sample than to the controls. In female subjects, T-allele of GNB3 polymorphism increases the risk of being a treatment-resistant patient with MDD. Moreover, in females the combination of TPH1 CC and GNB3 CT + TT genotype is associated with an increased risk of belonging to the patient group.

RGS4 genotype is not associated with antipsychotic medication response in schizophrenia.

The aims of the present study were to compare the allele frequencies of a common single nucleotide polymorphism located upstream of the regulator of G-protein signaling 4 (RGS4) gene (T > G, Rs 951436) in 219 Finnish patients with schizophrenia and in 389 control subjects, to analyze corresponding frequencies between two different subtypes of 93 schizophrenia patients according to their medication response, and to study the effect of this SNP on age at onset in schizophrenia. The RGS4 (T > G, Rs 951436) genotype was not associated with incidence or age at onset in schizophrenia. Neither was the RGS4 genotype associated with medication response with two different subpopulations with schizophrenia.

Increased expression of high mobility group A proteins in lung cancer.

High mobility group A (HMGA) proteins play an important role in the regulation of transcription, differentiation, and neoplastic transformation. In this work, the expression of HMGA 1 and 2 in 152 lung carcinomas of mainly non-small-cell histological type has been studied by immunohistochemistry in order to evaluate their feasibility as lung cancer markers. In 17 lung cancer cases, the related bronchial epithelial changes were also studied for HMGA1 and 2 expression. RNA expression of HMGA1a and b isoforms and of HMGA2 was determined by real-time semi-quantitative RT-PCR in 23 lung carcinomas. High expression of HMGA1 and HMGA2 at both mRNA and protein levels was detected in lung carcinomas, compared with normal lung tissue. Nuclear immunostaining for HMGA1 and 2 proteins also occurred in hyperplastic, metaplastic, and dysplastic bronchial epithelium. Increased nuclear expression of HMGA1 and 2 correlated with poor survival (for adenocarcinomas, HMGA1, p=0.006; HMGA2, p=0.05). While the expression of HMGA2 was significantly associated with cell proliferation (p=0.008), HMGA1 expression did not show any association with proliferation or apoptotic index. Sequencing of HMGA2 transcripts from tumours with very high expression showed a normal full-length transcript. As HMGA proteins were expressed in about 90% of lung carcinomas and their expression was inversely associated with survival, they may provide useful markers for lung cancer diagnosis and prognosis.

Radiofrequency ablation in the liver close to the bile ducts: can intraductal cooling offer protection?

BACKGROUND: One complication of radiofrequency ablation (RFA) of the liver is biliary duct damage. Intraductal cooling (IDC) has been proposed as a means of protection. METHODS: In the first experiment, designed to evaluate the influence of IDC on the RFA procedure per se and on lesion formation, lesions were created in vivo in pig liver with and without IDC. The RFA needle was placed with a 1.5-cm safety margin from the bile ducts. In the second experiment, designed to evaluate the potential protective effects of IDC, lesions were created close to a bile duct with and without IDC. RESULTS: With the safety margin, the RFA parameters and lesion size were not negatively affected by IDC. Microscopic examination revealed that IDC had a protective effect in most of the lesions created close to a bile duct. CONCLUSIONS: The IDC procedure was feasible and had no negative effect on the RFA procedure or the lesions. However, the protective effect of IDC was not statistically significant (p = 0.12).

L1CAM, INP10, P-cadherin, tPA and ITGB4 over-expression in malignant pleural mesotheliomas revealed by combined use of cDNA and tissue microarray.

Malignant pleural mesothelioma (MM) is a rare tumour with high mortality, which can exhibit various morphologies classified as epithelioid, biphasic and sarcomatoid subtypes. To investigate the molecular changes in these tumours, we studied gene expression patterns by combined use of cDNA arrays and tumour tissue microarrays (TMA). Deregulation of the expression of 588 cancer-related genes was screened in 16 MM comprising all three subtypes and compared with references, i.e. normal mesothelial cell lines and pleural mesothelium. Array data were analysed using three statistical methods; principal component analysis (PCA), permutation test and receiver operating characteristic (ROC) curves. Eleven genes were verified by real-time RT-PCR. Genes encoding two adhesion molecules [COL1A2 and integrin beta4 (ITGB4)] and a chemokine (INP10) were up-regulated in MM compared with both the cell lines and pleural mesothelium. There was a type-specific up-regulation of semaphorin E, ITGB4 and P-cadherin in epithelioid MM, matrix metalloproteinase 9 (MMP9) and tissue-type plasminogen activator (tPA) in sarcomatoid MM and neural cell adhesion molecule L1 (L1CAM) and INP10 in biphasic MM. Immunohistochemistry on TMA containing 47 MM (26 epithelioid, 15 sarcomatoid and six biphasic) was performed for five proteins, ITGB4, P-cadherin, tPA, INP10 and L1CAM. INP10 expression was increased in MM in general compared with normal mesothelium, while increased expression of P-cadherin, L1CAM and ITGB4 was more specific in MMs exhibiting an epithelioid growth pattern. The over-expression of tPA was more frequent in epithelioid MM despite higher mRNA levels in sarcomatoid and biphasic MM. We conclude that several proteins, associated with cell adhesion either directly (ITGB4, L1CAM, P-cadherin) or as a regulatory factor (INP10), are differentially expressed in MM. In particular, INP10, ITGB4 and COL1A2 were up-regulated in MM compared with both reference sample types, suggesting a relationship with development of these tumours.

Lack of association between two polymorphisms of brain-derived neurotrophic factor and response to typical neuroleptics.

Several studies have connected brain-derived neurotrophic factor (BDNF) with treatment response to neuroleptics. In recent studies, the BDNF expression was reduced by typical neuroleptics. We conducted a retrospective study on 94 patients with schizophrenia and 98 controls. The BDNF G196A and C270T polymorphisms are not associated with treatment response to typical neuroleptics or with age at first hospitalization. Moreover, these polymorphisms of the BDNF gene are not associated with the risk of schizophrenia.

A review of the pharmacological and clinical profile of mirtazapine.

The novel antidepressant mirtazapine has a dual mode of action. It is a noradrenergic and specific serotonergic antidepressant (NaSSA) that acts by antagonizing the adrenergic alpha2-autoreceptors and alpha2-heteroreceptors as well as by blocking 5-HT2 and 5-HT3 receptors. It enhances, therefore, the release of norepinephrine and 5-HT1A-mediated serotonergic transmission. This dual mode of action may conceivably be responsible for mirtazapine's rapid onset of action. Mirtazapine is extensively metabolized in the liver. The cytochrome (CYP) P450 isoenzymes CYP1A2, CYP2D6, and CYP3A4 are mainly responsible for its metabolism. Using once daily dosing, steady-state concentrations are reached after 4 days in adults and 6 days in the elderly. In vitro studies suggest that mirtazapine is unlikely to cause clinically significant drug-drug interactions. Dry mouth, sedation, and increases in appetite and body weight are the most common adverse effects. In contrast to selective serotonin reuptake inhibitors (SSRIs), mirtazapine has no sexual side effects. The antidepressant efficacy of mirtazapine was established in several placebo-controlled trials. In major depression, its efficacy is comparable to that of amitriptyline, clomipramine, doxepin, fluoxetine, paroxetine, citalopram, or venlafaxine. Mirtazapine also appears to be useful in patients suffering from depression comorbid with anxiety symptoms and sleep disturbance. It seems to be safe and effective during long-term use.

CYP1A1 levels in lung tissue of tobacco smokers and polymorphisms of CYP1A1 and aromatic hydrocarbon receptor.

Induction of a polycyclic aromatic hydrocarbon-metabolizing cytochrome P450 isoform CYP1A1 is regulated by aromatic hydrocarbon receptor (AHR). High inducibility of CYP1A1, possibly due to genetic polymorphisms, has been considered to be a risk factor for lung cancer in tobacco smokers. The relationship between low or high pulmonary expression of CYP1A1 and polymorphic genotypes of CYP1A1 and AHR was investigated in 73 active smokers. CYP1A1 expression was determined in surgical lung samples by measuring ethoxyresorufin O-deethylase (EROD) activity and by immunostaining for CYP1A1 protein. The most common allelic variants of CYP1A1 and AHR in Finns, i.e. the MspI variant (CYP1A1*2A), I462V variant (CYP1A1*2B), and -459C to T variant of CYP1A1 and the R554K variant (AHR*2) of AHR were studied using polymerase chain reaction based methods. EROD activity correlated positively with the daily cigarette consumption (r = 0.45). There was additional variation in EROD activity independent of the amount of smoking e.g. among those who smoked one pack per day until the day of operation, EROD activity ranged from 4-142 (median 48) pmol/min/mg. The frequencies of the MspI, 462V, and -459T variant alleles of CYP1A1 and 554K variant allele of AHR were 0.158, 0.055, 0.055 and 0.075, respectively. No differences were observed in the frequencies of polymorphic genotypes between the smokers with low and those with high expression, when the relationship was studied using a regression analysis adjusted for cigarette consumption. Our results thus indicate that the interindividual variation of CYP1A1 levels in smokers' lung tissue is not attributable to genetic polymorphisms of CYP1A1 or AHR tested in this study.

Relationship of depressive symptoms to edentulousness, dental health, and dental health behavior.

We investigated the relationship of edentulousness, dental health, and dental health behavior to depressive symptoms in the 55-year-old population of Oulu (a medium-sized Finnish town), 780 of whom (78%) participated. The dental examination included an assessment of oral health status. Depressive symptoms were determined with the Zung Self-Rating Depression Scale (ZSDS). The participants were also asked about their dental health behavior, smoking habits, health, life satisfaction, and factors related to their work. Depressive symptoms were associated with edentulousness among non-smoker men. When further evaluated by logistic regression analysis, edentulousness was independently associated with depressive symptoms in this subpopulation (odds ratio = 6.4, confidence interval = 1.4-29.2) after adjusting for confounding factors. Depressive symptoms were not associated with dental caries, periodontal status, or number of teeth. The dentate women with high rates of depressive symptoms had a more negative attitude towards preserving their natural teeth, used sugary products more frequently, reported a longer time since their last dental visit, and tended to have a lower percentage of filled tooth surfaces than the non-depressed dentate women. The aspect of depression should be borne in mind by dentists when treating edentulous patients. On the other hand, certain subgroups of depressed patients might benefit from dental implant therapy. Thus, the importance of teamwork between clinicians, psychiatrists, and dentists is emphasized.

Cost-effectiveness of an innovative four-year post-discharge programme for elderly patients--prospective follow-up of hospital and nursing home use in project elderly and randomized controls.

The cost-effectiveness of a post-discharge programme on the use of hospital care and the continuity of care was assessed in an elderly cohort (n = 204) discharged from the city hospital. The participation rate was 97.6%, and the patients were aged 75 years or over and lived alone. The randomized controls (n = 204) received standard aftercare. During the follow-up the costs of university hospital care decreased by 52% in the intervention group and by 24% in the control group per patient year, compared with the costs in the year preceding the project. This happened despite the higher morbidity in the intervention group in terms of fractures and the use of university hospital care in the year preceding the project. There was also a tendency in the intervention group for the previous non-users of university hospital care to remain non-users during the follow-up. The costs of city hospital care increased by 16% and 5%, and of all hospital care by 1.3% and 0.2%, respectively. There were no differences in admissions to permanent care in the nursing homes. The intervention group did not make their first contact with the hospitals or permanent care in nursing homes earlier than the control group during the follow-up. The co-operation between hospital and domiciliary care and voluntary workers was well-suited to the innovative care of the elderly people.

Survival in operable non-small-cell lung cancer: role of p53 mutations, tobacco smoking and asbestos exposure.

Validated markers are needed to identify operable lung cancer patients with poor prognosis. About one-half of non-small-cell lung cancers (NSCLCs) carry a mutation in the p53 tumor-suppressor gene. We examined 101 NSCLC patients for surgical stage, completeness of resection, tobacco smoking, asbestos exposure, age, gender and p53 gene mutations as prognostic factors after a follow-up period of 4 years. Cox's multivariate regression model was applied to quantify the associations with overall and cancer-related survival. Patients with a wild-type p53 gene had an overall 4-year survival of 43% and those with a mutated p53 gene, 35%. In squamous-cell carcinoma, stage and heavy smoking, defined as the median of pack-years smoked, had prognostic significance for overall survival. Only stage was associated with poor cancer-related survival. Asbestos exposure was not associated with overall survival or cancer-related survival in squamous-cell carcinoma or adenocarcinoma. In adenocarcinoma, p53 mutation, in addition to stage, emerged as a significant predictor of poor cancer-related survival.

Expression of CYP1A1, CYP1B1 and CYP3A, and polycyclic aromatic hydrocarbon-DNA adduct formation in bronchoalveolar macrophages of smokers and non-smokers.

Variability in the expression of enzymes metabolizing carcinogens derived from cigarette smoke may contribute to individual susceptibility to pulmonary carcinogenesis. This study was designed to determine the effects of smoking and 3 major cytochrome P450 (CYP) enzymes, i.e., CYP1A1, CYP1B1 and CYP3A, which metabolize polycyclic aromatic hydrocarbons (PAH) on PAH-DNA adduct formation in the bronchoalveolar macrophages (BAM) of 31 smokers and 16 non-smokers. CYP protein levels were determined by immunoblotting and PAH-DNA adduct levels by the nuclease P1 enhanced (32)P-postlabeling method. The expression of specific CYP forms was confirmed by reverse transcriptase-polymerase chain reaction (RT-PCR) from 10 additional samples. CYP3A protein, CYP3A5 by RT-PCR, was detected in the majority of samples from smokers and non-smokers. The levels of CYP3A appeared to be lower in active smokers than in ex-smokers (p = 0.10) or never smokers (p = 0.02). CYP1A1 was not detectable by either immunoblotting or RT-PCR. The expression of CYP1B1 was low or undetectable in most samples. The PAH-DNA adduct levels were higher (mean 1.57/10(8) nucleotides) in samples from smokers compared with non-smokers (mean 0.42/10(8) nucleotides, p < 0.001) and the number of adducts correlated with the number of cigarettes smoked daily (regression analysis, p < 0. 001). Higher levels of adducts were detected in samples from smokers with a high level of CYP3A compared with those with a low level (regression analysis, p = 0.002). As CYP3A5 is abundant in both lung epithelial cells and BAM, its association with adduct formation suggests that this CYP form may be important in the activation of cigarette smoke procarcinogens.

A broad amplification pattern at 3q in squamous cell lung cancer--a fluorescence in situ hybridization study.

Frequent DNA copy number gain at 3q, with minimal overlapping area at 3q24-qter, has previously been reported in squamous cell carcinoma of the lung (SQCC), implicating the importance of genes at 3q in the tumorigenesis of SQCC. To further characterize the gain of DNA sequences at 3q, we performed interphase fluorescence in situ hybridization (FISH) analysis on 16 paraffin-embedded SQCC tumor samples that had previously been studied by comparative genomic hybridization (CGH). Eleven yeast artificial chromosome (YAC) probes located at 3q25-q27 and a chromosome 3-specific centromeric probe were used in the analysis. All SQCC tumors showed increase in DNA sequence copy number with 9-11 probes. In 5 tumors (31%) the number of centromeric signals varied from 3 to 5 and the YAC/centromeric signal ratio was 1.0, suggesting that the increase in DNA sequence copy number at 3q in these cases resulted from polysomy of chromosome 3. In 11 tumors (69%), the YAC/centromeric signal ratio varied between 1.5 and 4.7, indicating that the increase in DNA sequence copy number was due to intrachromosomal gain of DNA sequences at 3q. In each case, several YACs showed increased number of signals, demonstrating that the gained area was relatively large. Our findings therefore suggest that multiple genes located at 3q25-q27 are involved in the tumorigenesis of SQCC.

An uncommon phenotype of poor inducibility of CYP1A1 in human lung is not ascribable to polymorphisms in the AHR, ARNT, or CYP1A1 genes.

Cigarette smoking can induce CYP1A1 in the lung. Induction requires the aryl hydrocarbon receptor (AHR) and aryl hydrocarbon receptor nuclear translocator (ARNT) proteins. Lung samples from seven of 75 Finnish patients who smoked until the time of surgery exhibited absent or low levels of CYP1A1 protein, mRNA and enzymatic activity, suggesting that these individuals might be genetically non or poorly inducible for CYP1A1. All seven lung samples expressed normal levels of AHR mRNA and ARNT mRNA, indicating that they did not carry inactivating polymorphisms in the 5' upstream regulatory regions of these genes. Sequencing of cDNAs encompassing the complete coding regions of AHR and ARNT identified a previously known codon 554 polymorphism in AHR, which was present in the homozygous state in one individual. This polymorphism, which leads to an amino acid substitution, has previously been reported either to have no effect or to enhance CYP1A1 induction. Previously unreported silent single nucleotide polymorphisms were identified in codon 44 of AHR and codon 189 of ARNT. 1500 bp of genomic sequence from the 5' upstream regulatory sequence of the CYP1A1 gene was also sequenced in the non-inducible individuals. A nucleotide substitution polymorphism at position -459 was detected in the heterozygous state in two individuals. This polymorphic site does not reside in any known regulatory sequence. The complete CYP1A1 coding sequence and intron/exon boundaries were then sequenced. None of the non or poorly inducible individuals exhibited any polymorphisms, either homozygous or heterozygous compared to representative inducible individuals or the previously published CYP1A1 sequence. Thus, no polymorphisms in the AHR, ARNT or CYP1A1 genes were identified that could be responsible for the non/low inducibility phenotype observed.

Depressive symptoms favor abundant growth of salivary lactobacilli.

OBJECTIVE: The purpose was to study the growth of lactobacilli in subjects with depressive symptoms in the total 55-year-old population of Oulu (a medium-sized town in Finland); 780 people participated. METHODS: The dental examination included measurements of salivary lactobacillus growth with the Dentocult-LB method; measurements of salivary flow rate, pH, and buffering capacity; and assessment of oral health status. Depressive symptoms were determined with the Zung Self-Rating Depression Scale (ZSDS). Participants were also asked about their health, medication, smoking, and dietary habits. RESULTS: The prevalence of high lactobacillus counts (> or =100,000 CFU/ml) was 22% among women and 31% among men (p = .02). Thirty-seven percent of the subjects with a high rate of depressive symptoms (ZSDS score of > or = 40) and 23% of those with an ZSDS score of < or = 39 had high counts of lactobacilli (p = .003). A logistic regression analysis with improvement of goodness of fit was made to confirm the relation between abundant lactobacilli and a high rate of depressive symptoms. After the confounding factors had been added stepwise into the logistic regression model, depressive symptoms were still significantly associated with abundant lactobacillus growth. CONCLUSIONS: The association between high lactobacillus counts and depressive symptoms suggests that depressed subjects are at risk of having caries and possibly other dental diseases that should be recognized in the treatment of these patients.