Circulating markers of cellular immune activation in prediagnostic blood sample and lung cancer risk in the Lung Cancer Cohort Consortium (LC3).

Cell-mediated immune suppression may play an important role in lung carcinogenesis. We investigated the associations for circulating levels of tryptophan, kynurenine, kynurenine:tryptophan ratio (KTR), quinolinic acid (QA) and neopterin as markers of immune regulation and inflammation with lung cancer risk in 5,364 smoking-matched case-control pairs from 20 prospective cohorts included in the international Lung Cancer Cohort Consortium. All biomarkers were quantified by mass spectrometry-based methods in serum/plasma samples collected on average 6 years before lung cancer diagnosis. Odds ratios (ORs) and 95% confidence intervals (CIs) for lung cancer associated with individual biomarkers were calculated using conditional logistic regression with adjustment for circulating cotinine. Compared to the lowest quintile, the highest quintiles of kynurenine, KTR, QA and neopterin were associated with a 20-30% higher risk, and tryptophan with a 15% lower risk of lung cancer (all ptrend < 0.05). The strongest associations were seen for current smokers, where the adjusted ORs (95% CIs) of lung cancer for the highest quintile of KTR, QA and neopterin were 1.42 (1.15-1.75), 1.42 (1.14-1.76) and 1.45 (1.13-1.86), respectively. A stronger association was also seen for KTR and QA with risk of lung squamous cell carcinoma followed by adenocarcinoma, and for lung cancer diagnosed within the first 2 years after blood draw. This study demonstrated that components of the tryptophan-kynurenine pathway with immunomodulatory effects are associated with risk of lung cancer overall, especially for current smokers. Further research is needed to evaluate the role of these biomarkers in lung carcinogenesis and progression.

Reproductive and hormonal factors and the risk of lung cancer: the EAGLE study.

Evidence about the role for reproductive and hormonal factors in the etiology of lung cancer in women is conflicting. To clarify this question, we examined 407 female cases and 499 female controls from the Environment And Genetics in Lung cancer Etiology population-based case-control study. Subjects were interviewed in person using a computer-assisted personal interview to assess demographics, education, smoking history, medical history, occupational history, reproductive and hormonal factors. Associations of interest were investigated using logistic regression models, adjusted for catchment area and age (matching variables), cigarette smoking (status, pack-years and time since quitting). Additional confounding variables were investigated but did not substantially affect the results. We observed a reduced risk of lung cancer among women with later age at first live birth [≥31 years: odds ratio (OR) = 0.57, 95% confidence interval (CI) = 0.31-1.06, p-trend = 0.05], later age at menopause (≥51 years: OR = 0.49, 95%CI = 0.31-0.79, p-trend = 0.003) and longer reproductive periods (≥41 years: OR = 0.44, 95%CI = 0.25-0.79, p-trend = 0.01). A reduced risk was also observed for hormone replacement therapy (OR = 0.63, 95%CI = 0.42-0.95, p = 0.03) and oral contraceptive use (OR = 0.67, 95%CI = 0.45-1.00, p = 0.05) but no trend with duration of use was detected. Menopausal status (both natural and induced) was associated with an augmented risk. No additional associations were identified for other reproductive variables. This study suggests that women who continue to produce estrogens have a lower lung cancer risk. Large studies with great number of never smoking women, biomarkers of estrogen and molecular classification of lung cancer are needed for a more comprehensive view of the association between reproductive factors and lung cancer risk.

Detection of Merkel cell polyomavirus with a tumour-specific signature in non-small cell lung cancer.

BACKGROUND: We searched for a viral aetiology for non-small cell lung cancer (NSCLC), focusing on Merkel cell polyomavirus (MCPyV). METHODS: We analysed 112 Japanese cases of NSCLC for the presence of the MCPyV genome and the expressions of RNA transcripts and MCPyV-encoded antigen. We also conducted the first analysis of the molecular features of MCPyV in lung cancers. RESULTS: PCR revealed that 9 out of 32 squamous cell carcinomas (SCCs), 9 out of 45 adenocarcinomas (ACs), 1 out of 32 large-cell carcinomas, and 1 out of 3 pleomorphic carcinomas were positive for MCPyV DNA. Some MCPyV DNA-positive cancers expressed large T antigen (LT) RNA transcripts. Immunohistochemistry showed that MCPyV LT antigen was expressed in the tumour cells. The viral integration sites were identified in one SCC and one AC. One had both episomal and integrated/truncated forms. The other carried an integrated MCPyV genome with frameshift mutations in the LT gene. CONCLUSION: We have demonstrated the expression of a viral oncoprotein, the presence of integrated MCPyV, and a truncated LT gene with a preserved retinoblastoma tumour-suppressor protein-binding domain in NSCLCs. Although the viral prevalence was low, the tumour-specific molecular signatures support the possibility that MCPyV is partly associated with the pathogenesis of NSCLC in a subset of patients.

The polymorphisms and haplotypes of WWOX gene are associated with the risk of lung cancer in southern and eastern Chinese populations.

The WW domain-containing oxidoreductase (WWOX) gene is an identified tumor suppressor gene, of which several single nucleotide polymorphisms have been reported to contribute to cancer susceptibility. We hypothesized that genetic variations in WWOX are associated with lung cancer risk. In two independent case-control studies conducted in southern and eastern Chinese, we genotyped five tagSNPs of WWOX gene (rs10220974C > T, rs3764340C > G, rs12918952G > A, rs383362G > T, and rs12828G > A) in 1,559 lung cancer cases and 1,679 controls. Logistic regression analysis showed that two tagSNPs (rs3764340C > G; rs383362G > T) were significantly associated with lung cancer risk in dominant model (rs3764340C > G, GC/GG vs. CC: adjust OR = 1.35, 95% CI = 1.11-1.65; rs383362G > T, TG + TT vs. GG: adjust OR = 1.33, 95% CI = 1.14-1.55). The haplotype analysis further shown that the haplotype "G-T" was associated with the highest increased risk of lung cancer (OR = 2.20; 95% CI = 1.43-3.37). After combined these two loci, the number of the risk genotypes was associated with increased cancer risk in a dose-response manner (Ptrend = 3.16 × 10(-6) ). In addition, a gene-based association analysis by using VEGAS software suggested the WWOX as a susceptible gene for lung cancer (P = 0.009). However, for rs10220974C > T, rs12918952G > A, and rs12828G > A, no significant association was observed for lung cancer risk. Taken together, our data suggested that genetic variants in WWOX may be genetic biomarkers for susceptibility to lung cancer.

A functional trinucleotide repeat polymorphism in the 5'-untranslated region of the glutathione biosynthetic gene GCLC is associated with increased risk for lung and aerodigestive tract cancers.

Glutathione (GSH), the major intracellular antioxidant, protects against cancer development by detoxifying carcinogens and free radicals and strengthening the immune system. Recently, a GAG-trinucleotide repeat polymorphism in the 5'-untranslated region of the gene for the rate-limiting enzyme for GSH biosynthesis, γ-glutamine cysteine ligase (GCL), was shown to be associated with lowered GCL activity and GSH levels in vitro and in vivo. We tested the hypothesis that this functional polymorphism in GCL is associated with the risk for lung and aerodigestive tract cancers. To this end, we conducted a case-control study that included 375 lung cancer cases, 200 aerodigestive tract cancer cases, and 537 controls. GAG repeat genotype (4, 7, 8, 9, and 10 repeat alleles) was determined by capillary electrophoresis of PCR products from the repeat region of the GCL catalytic subunit (GCLC). Odds ratios (OR) were calculated by logistic regression and adjusted for risk factors, including age, sex, body mass index, and smoking history. The GAG-7/7 genotype was associated with a 1.9-fold increased risk of lung cancer and 2.6-fold increased risk of aerodigestive tract cancer compared to the wild-type GAG-9/9 (P < 0.05). Similarly, the GAG-7 allele was associated with an increased risk of lung cancer (OR = 1.5, P = 0.01) and aerodigestive tract cancer (OR = 2.3, P < 0.001) compared to subjects without GAG-7 allele. These findings suggest that GSH synthesis affects the risk of lung and aerodigestive tract cancers, and further implicates a role for oxidative stress in the development of these cancers.

Sipa1 promoter polymorphism predicts risk and metastasis of lung cancer in Chinese.

Signal-induced proliferation associated gene 1 (Sipa1) is a signal transducer to activate the Ras-related proteins and modulate cell progression, differentiation, adhesion and cancer metastasis. In this study, we tested the hypothesis that single nucleotide polymorphisms (SNPs) in Sipa1 are associated with lung cancer risk and metastasis. Three common SNPs (rs931127A > G, rs2448490G > A, and rs3741379G > T) were genotyped in a discovery set of southern Chinese population and then validated the promising SNPs in a validation set of an eastern Chinese population in a total of 1559 lung cancer patients and 1679 cancer-free controls. The results from the two sets were consistent, the rs931127GG variant genotype had an increased risk of lung cancer compared to the rs931127AA/GA genotypes (OR = 1.27; 95% CI = 1.09-1.49) after combination of the two populations, and the rs931127GG interacted with pack-year smoked on increasing lung cancer risk (P = 0.037); this SNP also had an effect on patients' clinical stages (P = 0.012) that those patients with the rs931127GG genotype had a significant higher metastasis rate and been advanced N, M stages at diagnosis. However, these associations were not observed for rs2448490G > A and rs3741379G > T in the discovery set. Our data suggest that the SNP rs931127A > G in the promoter of Sipa1 was significantly associated with lung cancer risk and metastasis, which may be a biomarker to predict the risk and metastasis of lung cancer.

Functional genetic variants of c-Jun and their interaction with smoking and drinking increase the susceptibility to lung cancer in southern and eastern Chinese.

Human proto-oncogene c-Jun and c-Fos assemble the activator protein-1 complex which is a crucial transcription factor responding to environmental factors and promotes tumorgenesis. We hypothesized that genetic variants in these two genes may alter the carriers' susceptibility to lung cancer. In two independent case-control studies, we genotyped three putative functional polymorphisms (-1318T>G and -673T>C of c-Jun; -60C>T of c-Fos) in southern Chinese and then validated the association in eastern Chinese. We found that compared to -1318TT genotype, the -1318GT/GG variant genotypes had an increased lung cancer risk (OR=1.46, 95% CI=1.26-1.69), and the -673CC genotype had an increased lung cancer risk compared to -673TT/CT genotypes (OR=1.35, 95% CI=1.17-1.56) in the total 1,559 cases versus 1,679 controls. After combining these two loci, the number of the risk genotypes was associated with increased cancer risk in a dose-response manner (ptrend=2.21×10(-11)); moreover, the risk genotypes interacted with smoking or drinking status on increasing cancer risk (p values of interaction were 0.009 and 0.007, respectively). Further, we found that those with -1318GT/GG genotypes, -673CC genotypes or both genotypes in c-Jun had higher mRNA and protein expression levels in vivo, and those variants had higher transcription activities in reporter genes in vitro, especially under the stimuli with tobacco extract or alcohol mixture as luciferase assay shown. However, for -60C>T of c-Fos, no significant association was observed for lung cancer risk. Our data suggested that the genetic variants in c-Jun (-1318T>G and -673T>C) increase the carriers' susceptibility to lung cancer via interaction with smoking or drinking on increasing the c-Jun's expression.

Urinary Tract Large Cell Neuroendocrine Carcinoma: Diagnostic, Prognostic and Therapeutic Issues.

Large cell neuroendocrine carcinoma (LCNEC) of the urinary tract is a high-grade neuroendocrine tumor with distinct pathological features, usually portending an aggressive clinical behavior in comparison to conventional urothelial carcinoma. Due to its low prevalence, little is known about its clinical management and there is no current standard of care. The aim of this review was to summarize the current knowledge about LCNEC of the bladder, ureter and kidney, with relevance to diagnostic, prognostic and therapeutic issues, through a systematic analysis of clinical, pathological and outcome data retrieved from the literature.

Characteristics of menstruation and pregnancy and the risk of lung cancer in women.

Lung tissue, both normal and cancerous, has been found to express estrogen receptors and patterns of expression have differed between men and women, suggesting a possible role for hormone-related factors in lung carcinogenesis in women. Few epidemiological studies have examined hormone-related variables and lung cancer risk and the findings have not been consistent. We investigated the association between characteristics of menstruation and pregnancy in relation to lung cancer risk in a population-based case-control study carried out in Montreal, Canada, including 422 women with lung cancer and 577 controls. For each variable, odds ratios (OR) and 95% confidence intervals (CI) were estimated using unconditional logistic regression modeling. Associations were also examined according to level of smoking and by lung cancer histology. All statistical tests were two-sided. Most characteristics of menstruation and pregnancy were not associated with lung cancer risk. However, an increased risk was observed for women who had had a non-natural menopause, which predominantly included women who had had a bilateral oophorectomy, compared with women who had had a natural menopause (OR = 1.92, 95% CI: 1.22-3.01). An inverse association with age at menopause was suggested. These results did not vary by level of smoking and they were similar for adenocarcinomas compared with other histological types. Our results suggest that hormonal factors, related to early menopause and/or ovary removal, may play a role in the risk of lung cancer. Further studies are needed to confirm these findings, and to assess the possible contribution of hormone replacement therapy.

Environmental tobacco smoke and lung cancer among Chinese nonsmoking males: might adenocarcinoma be the culprit?

No studies have specifically reported the association of lung adenocarcinoma with environmental tobacco smoke (ETS) exposure among nonsmoking males. The objective of this study was to examine the exposure-response relation between ETS exposure and lung cancer among nonsmoking males. In particular, the association with adenocarcinoma of the lung was studied. This is a population-based, case-referent study in Hong Kong during 2004-2006. A total of 132 Chinese male nonsmokers with newly diagnosed primary lung cancer and 536 nonsmoking community referents were interviewed about ETS exposures from the household and/or workplace, including ever ETS exposure, sources of exposure, number of smoking cohabitants/coworkers, and smoker-years. Univariate logistic regression analyses showed a weak association between all lung cancers and ever ETS exposure from the household and/or workplace (odds ratio (OR) = 1.11, 95% confidence interval (CI): 0.74, 1.67), but an increased risk was restricted to adenocarcinoma (OR = 1.68, 95% CI: 1.00, 2.38). After adjustment for family cancer history and other confounders, excess risk (OR = 1.62, 95% CI: 0.91, 2.88) still persisted for adenocarcinoma, although it was no longer statistically significant. Exposure-response relations for adenocarcinoma were found with increasing levels of all ETS indices when exposures from the household and workplaces were combined. The consistent exposure-response relations between ETS exposures and adenocarcinoma suggested a probable causal link, which would have to be confirmed by future larger studies.

Marijuana use and the risk of lung and upper aerodigestive tract cancers: results of a population-based case-control study.

BACKGROUND: Despite several lines of evidence suggesting the biological plausibility of marijuana being carcinogenic, epidemiologic findings are inconsistent. We conducted a population-based case-control study of the association between marijuana use and the risk of lung and upper aerodigestive tract cancers in Los Angeles. METHODS: Our study included 1,212 incident cancer cases and 1,040 cancer-free controls matched to cases on age, gender, and neighborhood. Subjects were interviewed with a standardized questionnaire. The cumulative use of marijuana was expressed in joint-years, where 1 joint-year is equivalent to smoking one joint per day for 1 year. RESULTS: Although using marijuana for > or =30 joint-years was positively associated in the crude analyses with each cancer type (except pharyngeal cancer), no positive associations were observed when adjusting for several confounders including cigarette smoking. The adjusted odds ratio estimate (and 95% confidence limits) for > or =60 versus 0 joint-years was 1.1 (0.56, 2.1) for oral cancer, 0.84 (0.28, 2.5) for laryngeal cancer, and 0.62 (0.32, 1.2) for lung cancer; the adjusted odds ratio estimate for > or =30 versus 0 joint-years was 0.57 (0.20, 1.6) for pharyngeal cancer, and 0.53 (0.22, 1.3) for esophageal cancer. No association was consistently monotonic across exposure categories, and restriction to subjects who never smoked cigarettes yielded similar findings. CONCLUSIONS: Our results may have been affected by selection bias or error in measuring lifetime exposure and confounder histories; but they suggest that the association of these cancers with marijuana, even long-term or heavy use, is not strong and may be below practically detectable limits.

Metabolic phenotypes of retinoic acid and the risk of lung cancer.

The metabolic activity of cytochrome P-450 enzymes has been associated with an increased risk of developing lung cancer. We found previously that all-trans retinoic acid is catabolized by these oxidative enzymes, and that an inhibitor of this system discriminated between two populations of lung cancer patients. We examined the association between this metabolic phenotype and the risk of lung cancer in 85 subjects. The area under the plasma concentration x time curve (AUC) was calculated after a single oral dose of all-trans retinoic acid (45 mg/m2). The mean AUC for patients who had either squamous or large cell carcinomas was significantly lower than that of patients with adenocarcinomas (P = 0.0001) or control subjects (P = 0.01). Individuals with an AUC < 250 ng x h/ml had a greater likelihood of having squamous or large cell carcinoma (odds ratio = 5.93). This study suggests that the "rapid" catabolism of all-trans retinoic acid is linked to an increased risk of squamous or large cell cancers of the lung.

k-ras mutation and occupational asbestos exposure in lung adenocarcinoma: asbestos-related cancer without asbestosis.

Environmental carcinogen exposure is requisite for the development of nearly all lung cancer, and it is well known that asbestos exposure interacts synergistically with tobacco smoke to induce lung cancer. However, the precise molecular lesions induced by asbestos are unknown. Furthermore, it is also unknown whether asbestos carcinogenesis proceeds in a fashion independent of or dependent upon the induction of fibrosis in workers with high asbestos exposures. Previous studies have suggested that asbestos is associated with the presence of a k-ras mutation in adenocarcinoma of the lung. We aimed to test whether occupational asbestos exposure was associated with k-ras codon 12 mutations in lung adenocarcinoma tumors and to determine whether this was conditional on the presence of asbestosis. All newly diagnosed, resectable lung cancer patients receiving treatment at the Massachusetts General Hospital between November 1992 and December 1996 were eligible to participate. Because k-ras mutation is very strongly associated with adenocarcinoma, and men were more likely to be occupationally exposed to asbestos, the study was restricted to males with this histological diagnosis. There were 84 male patients with available questionnaire-derived work history data and paraffin-embedded tumor tissue for determination of k-ras mutation status. Chest radiographic evaluation was done for all of the patients who reported occupational exposure to asbestos. The prevalence of k-ras mutation was higher among those with a history of occupational asbestos exposure (crude odds ratio, 4.8; 95% confidence interval, 1.5-15.4) compared to those without asbestos exposure, and this association remained after adjustment for age and pack-years smoked (adjusted odds ratio, 6.9; 95% confidence interval, 1.7-28.6). An index score that weights both the dates of exposure and the estimated intensity of exposure indicated that those with k-ras mutations had significantly greater asbestos exposures than those without mutations (P < 0.01). Analysis of the descriptive components of exposure indicated that the duration of exposure was not associated with k-ras mutation, but that the time since initial exposure was significantly associated with mutation status. The association of k-ras mutation and reported asbestos exposure was not dependent on the presence of radiographic evidence of asbestos-related disease. These data suggest that asbestos exposure increases the likelihood of mutation at k-ras codon 12 and that this process occurs independently of the induction of interstitial fibrosis.

XRCC1 polymorphism and lung cancer risk in relation to tobacco smoking.

DNA repair plays a critical role in protecting the genome of the cell from carcinogens or ionising radiation. Reduced DNA-repair capacity can increase susceptibility to occupational-induced cancer. Three coding polymorphisms at codons 194, 280, and 399 in X-ray cross complementing group 1 (XRCC1) DNA-repair gene have been identified, and it is possible that these polymorphisms may affect DNA- repair capacity and thus modulate cancer susceptibility. In the current German study, we investigated the role of XRCC1-polymorphisms as a genetic modifier of risk for individuals with lung cancer as susceptible genotypes, especially in relation to tobacco smoking. Three polymorphisms; XRCC1 Arg194Trp, XRCC1 Arg280His and XRCC1 Arg399Gln, were determined by real-time PCR analysis in 446 lung cancer patients and 622 controls. The observed allele frequencies in the population were within the range described for Caucasians. Multivariate analyses of lung cancer patients who carried at least one mutant variant allele of XRCC1 Arg194Trp (OR=1.03; 95%-CI: 0.66-1.61), XRCC1 Arg280His (OR=0.95; 95%-CI: 0.57-1.60), or XRCC1 Arg399Gln (OR=0.99 CI: 0.73-1.34), did not show any elevated risks. When analysed by histology, no individual subtype of lung cancer was significantly associated with the polymorphisms. Lung cancer risk rose significantly with higher cumulative cigarette consumption. Stratified analysis between tobacco smoking and variant genotypes revealed increasing risks for heavy smokers (>60 pack-years), with the presence of at least one copy of the XRCC1 Arg194Trp variant allele (OR=79.29; 95%-CI: 8.53-737.04) and the XRCC1 Arg399Gln (OR=61.87; 95%-CI: 15.65-244.67). By analysing the interaction between tobacco smoking and the genotypes, combined smoking and having the susceptible genotypes did not show a joint effect. In this study, the XRCC1 Arg194Trp, XRCC1 Arg280His, and XRCC1 Arg399Gln-polymorphisms, had no relevant modifying effect on lung cancer risk and cumulative smoking dose.

Lung cancer histopathology in the Thrace region of Turkey and comparison with national data.

Following the trends in lung cancer (LC) morbidity and mortality rates can show past trends of cigarette smoking and can give clues on some geographical factors. The demographics of LC patients and the histopathologic distribution of their disease in the Thrace region of Turkey have yet to be defined. A retrospective chart review of primary LC patients admitted to the pulmonology department of Trakya University Hospital between 1992 and 2001 was performed. Charts were available for review in 521 of 567 patients. The mean age was 61 +/- 10 years (30-86 years) and 497 (95.4%) patients were male (male/female ratio= 20.7). When compared with national and international data, male/female ratio for the LC patients from Thrace region was higher than the ratio found from Turkey in general and also from other countries. Adenocarcinoma (ADC) was present in seven of the 24 (29.2%) of the females and prevalence of ADC was more than 2.5 times in females than males (p< 0.05). Squamous cell types were more common in males. Histopathological type did not vary with age in females, but small cell carcinoma was more prevalent in males under the age of 45 (44.7% if . 45 years old vs. 29.1% if > 45 years old, p< 0.05). These data may support that the LC associated with smoking is in the earlier phase of the epidemic in Thrace region. Monitoring the LC trend in our region can give clues on evolving cigarette design and smoking attitudes and geographic factors.

Large cell carcinoma of the lung: a tumor in search of an author. A clinically oriented critical reappraisal.

Large cell carcinoma (LCC) is a merely descriptive term indicating a subtype of lung cancer with no specific features of small-cell lung cancer (SCLC), adenocarcinoma (ADC) or squamous cell carcinoma (SQC). This diagnosis is allowed on surgical specimens only, whereas its counterpart in biopsy/cytology samples is non-small-cell lung carcinoma (NSCLC), not otherwise specified (NOS). Although these two terms do not fulfill the same concept, they can be interchangeable synonyms at the clinical level, reflecting, in different ways, the inability to define a specific subtype. Immunohistochemistry (IHC), next generation sequencing (NGS) analysis and, historically, electron microscopy have been unveiling diverse cell differentiation lineages in LCC, resulting in LCC-favor ADC, LCC-favor SQC and LCC-favor large-cell neuroendocrine carcinoma (LCNEC), the latter hopefully to be included into the neuroendocrine tumor (NET) group in the future. Paradoxically, however, the interpretation issues of LCC/NSCLC-NOS are not diminishing, but even increasing albeight an accurate diagnosis is oncologically required and crucial. Also, rare LCC/NSCLC-NOS cases exhibiting null/unclear phenotype, are difficult to classify, and this terminology could be maintained for the sake of classification (basically these tumors are serendipitous ADC, as also confirmed by the lack of p40). In this review article, seven relevant issues to LCC have been addressed by using a question-answer methodology, with final key points discussing major interpretation issues. In conclusion, most LCC/NSCLC-NOS may be eventually re-classified and addressed by exploiting IHC and/or molecular testing to satisfy the criteria of precision medicine (the right drug, to the right patient, at the right time).

Cigarette smoking and large cell carcinoma of the lung.

Large cell carcinoma is the fourth most common histological type of lung cancer in the United States. Cigarette smoking causes large cell lung cancer, but it is uncertain whether the effect varies with the amount and duration of smoking. This uncertainty stems from ambiguity in the histopathological classification of large cell cancer, especially before 1971, and the relatively infrequent occurrence of large cell cancer in epidemiological studies. The present case-control investigation demonstrates that the risk of large cell cancer increases with both the frequency and number of years of cigarette smoking. The odds ratio associated with smoking two or more packs/day was 37.0 (95% confidence interval, 16.4-83.2) in men and 72.9 (35.4-150.2) in women. It is concluded that cigarette smoking is the predominant cause of large cell lung cancer.

GSTM1, GSTT1, and GSTP1 polymorphism and lung cancer risk in relation to tobacco smoking.

The impact of genetic polymorphisms in GSTM1, GSTP1 or GSTT1 on susceptibility to lung cancer has received particular interest since these enzymes play a central role in detoxification of major classes of tobacco carcinogens. In the current German study we investigated the role of GSTM1, GSTT1 and GSTP1 polymorphisms as a genetic modifier of risk for individuals with lung cancer as susceptible genotypes especially in relation to tobacco smoking. The GSTM1, the GSTP1 as well as GSTT1-polymorphism were determined by real time PCR analysis in 446 lung cancer patients and 622 controls. The observed allele frequencies of the GSTP1 polymorphism in the population were within the range described for Caucasians. Multivariate analyses of lung cancer patients, who carried at least one mutant variant allele of GSTP1 (OR=1.03; 95%-CI: 0.76-1.39) did not show any elevated risks. GSTM1 or GSTT1 null-genotypes were found in 47.3% resp. 18.5% of the controls and in 52.5% resp. 16.8% of the cancer patients. The estimated risk of the GSTM1 null genotype for lung cancer was OR=1.34 (95%-CI: 0.99-1.81) and for the GSTT1 null genotype OR=0.88 (95%-CI: 0.59-1.32). When analyzed by histology no individual subtype of lung cancer was strongly associated with the polymorphisms. Lung cancer risk rose significantly with higher cumulative cigarette consumption confirming the association with smoking-related lung cancer risk. Stratified analysis between tobacco smoking and variant genotypes revealed for heavy smokers (>60 pack-years) increasing risks at the presence for at least one copy of the GSTP1 variant allele OR=50.56 (95%-CI: 15.52-164.79). The corresponding risks for GSTM1 null genotypes were OR=112.08 (95%-CI: 23.02-545.71) and for the GSTT1 null-genotype OR=158.49 (95%-CI: 17.75-1415.06) in smokers >60 pack-years. Analysing the interaction between tobacco smoking and the genotypes, combined smoking and having the susceptible genotypes did not show a joint effect. In this study polymorphisms of the GSTM1, GSTT1 or GSTP1 had no relevant modifying effect on lung cancer risk and cumulative smoking dose.

Frequent cyclin D1 expression in chromate-induced lung cancers.

Ex-chromate workers are frequently afflicted with lung cancers, especially central-type squamous cell carcinomas (SCCs) of the lung. However, little is known about the molecular and cellular biologic characteristics of chromate-induced lung cancers. We investigated expression of cyclin D1, bcl-2, and p53 proteins in chromate-induced lung cancers by immunohistochemistry, compared with those in lung cancers from nonexposed individuals and those in individuals with pneumoconiosis. Of 19 chromate-induced lung cancers, 16 tumors were SCCs, including 11 central and 5 peripheral types. Eleven (69%) of 16 chromate SCCs showed cyclin D1 expression. In contrast, cyclin D1 expression was observed in only 3 (12%) of 26 SCCs from nonexposed individuals and 6 (16%) of 37 SCCs that developed in patients with pneumoconiosis, respectively. The frequency of cyclin D1 expression proved to be significantly higher in chromate-induced SCCs than in SCCs from nonexposed individuals and from those with pneumoconiosis (P < .001). When comparisons were extended to all histologic types of lung cancer, cyclin D1 expression was observed significantly more often in chromate-induced lung cancers than in lung cancers from nonexposed subjects and those from patients with pneumoconiosis (11 [58%] of 19 v 5 [10%] of 52, P < .001, and 7 [11%] of 63, P < .001, respectively). Frequencies of bcl-2 and p53 expression were not significantly different among lung cancers from ex-chromate workers, nonexposed individuals and those with pneumoconiosis. The current study suggests that cyclin D1 expression may be involved in the development of chromate-induced lung cancers, although its underlying mechanism remains to be determined.

Bronchogenic carcinoma in patients seropositive for human immunodeficiency virus.

The purpose of this report is to describe an association between bronchogenic carcinoma and HIV. Three HIV-seropositive patients are described who developed bronchogenic cancer (two large cell, one adenocarcinoma) before developing an AIDS-defining illness. A critical review of the literature revealed 22 other patients in which the association of HIV infection and lung cancer is reported. These patients are characterized by a relatively young age at diagnosis (median, 43 years) and prevalence of the adenocarcinoma subtype (13 of 25 patients). Twenty of 21 patients had a history of smoking. Among 21 patients for whom data were available, 6 patients (28 percent) had AIDS at time of diagnosis of lung cancer while 11 patients (55 percent) did not have AIDS or AIDS-related complex at diagnosis.