Nonsteroidal Antiinflammatory Drug Use and Lung Cancer

Transcriptomic analysis reveals particulate hexavalent chromium regulates key inflammatory pathways in human lung fibroblasts as a possible mechanism of carcinogenesis

Hexavalent chromium [Cr(VI)] is considered a major environmental health concern and lung carcinogen. However, the exact mechanism by which Cr(VI) causes lung cancer in humans remains unclear. Since several reports have demonstrated a role for inflammation in Cr(VI) toxicity, the present study aimed to apply transcriptomics to examine the global mRNA expression in human lung fibroblasts after acute (24 h) or prolonged (72 and 120 h) exposure to 0.1, 0.2 and 0.3 μg/cm2 zinc chromate, with a particular emphasis on inflammatory pathways. The results showed Cr(VI) affected the expression of multiple genes and these effects varied according to Cr(VI) concentration and exposure time. Bioinformatic analysis of RNA-Seq data based on the Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and MetaCore databases revealed multiple inflammatory pathways were affected by Cr(VI) treatment. qRT-PCR data corroborated RNA-Seq findings. This study showed for the first time that Cr(VI) regulates key inflammatory pathways in human lung fibroblasts, providing novel insights into the mechanisms by which Cr(VI) causes lung cancer.

Stromal inflammation, fibrosis and cancer: An old intuition with promising potential

It is now well established that the biology of cancer is influenced by not only malignant cells but also other components of the tumour microenvironment. Chronic inflammation and fibrosis have long been postulated to be involved in carcinogenesis. Chronic inflammation can promote tumorigenesis via growth factor/cytokine-mediated cellular proliferation, apoptotic resistance, immunosuppression; and free-radical-induced oxidative deoxyribonucleic acid damage. Fibrosis could cause a perturbation in the dynamics of the tumour microenvironment, potentially damaging the genome surveillance machinery of normal epithelial cells. In this review, we will provide an in-depth discussion of various diseases characterised by inflammation and fibrosis that have been associated with an increased risk of malignancy. In particular, we will present a comprehensive overview of the impact of alterations in stromal composition on tumorigenesis, induced as a consequence of inflammation and/or fibrosis. Strategies including the application of various therapeutic agents with stromal manipulation potential and targeted cancer screening for certain inflammatory diseases which can reduce the risk of cancer will also be discussed.

The association of aspirin use with overall survival of patients with inoperable non-small cell lung cancer: a retrospective study

Background

Studies have indicated that individuals taking aspirin have a reduced risk of cancers and have also established chemo-preventive benefit of aspirin in colorectal cancer. However, research on the association between aspirin use and the survival in patients with lung cancer has revealed inconsistent results. In this study, we investigated the effect of aspirin use on the survival of inoperable non-small cell lung cancer (NSCLC) patients.

Methods

We identified a cohort of 38,842 patients diagnosed with NSCLC between 2000 and 2012 using the Taiwan’s National Health Insurance Research Database and used propensity score matching to reduce possible confounding factors. In total, 9864 patients (4932 matched pairs) were included in the matched cohort. Aspirin exposure was analyzed to identify a possible association with mortality in patients with inoperable NSCLC. Time-dependent Cox regression models were used to calculate the hazard ratios (HRs) and the 95% confidence intervals (95% CIs) that corresponded with aspirin exposure.

Results

A total of 4979 patients used aspirin at the time of diagnosis of NSCLC. The median overall survival (OS) of the aspirin users was 1.73 (interquartile range, 0.94–3.53) years compared with the 1.30 (interquartile range, 0.69–2.62) years of the non-aspirin users. The Cox proportional hazard model with the time-dependent covariate revealed that aspirin use was associated with a significantly longer OS (HR: 0.83, 95.0% CI: 0.80–0.86). After controlling the sociodemographic characteristics (age, sex, income, and level of urbanization) and lung cancer treatments by propensity score matching, the aspirin users still had a significantly longer OS than the non-aspirin users (HR: 0.79, 95.0% CI: 0.75–0.83).

Conclusion

Aspirin use is associated with a longer OS in patients with inoperable NSCLC, suggesting that aspirin has a potential anticancer effect. These results warrant further randomized clinical trials to evaluate the actual role of aspirin in the treatment of NSCLC patients.

Association between aspirin use and lung cancer incidence depends on high-frequency use, bodyweight, and age in U.S. adults

Background

Chemoprevention of cancer with aspirin is controversial as a primary prevention strategy. We sought to investigate the association between aspirin frequency and risk of lung cancer in The Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial.

Methods

Using data from 101,722 participants in PLCO, we used a Cox regression model coupling with propensity score to detect the association between aspirin frequency and lung cancer risk.

Results

High-frequency aspirin use significantly increased risk of lung cancer by 28% compared to no use (HR =1.28; 95% CI, 1.14–1.45; P=3.37×10⁻⁵), especially for current smoker (HR =1.30; 95% CI, 1.07–1.57; P=6.82×10⁻³). However, the increased lung cancer risk due to high-frequency aspirin use significantly decreased with increasing bodyweight (HR_interaction =0.96; 95% CI, 0.94–0.99; P=1.26×10⁻²). Further, for participants with bodyweight <80 kg, high-frequency aspirin use showed an elevated risk at <76 years of age (HR_age<76 =1.47; 95% CI, 1.25–1.73; P=3.81×10⁻⁶). Our study used propensity score under various confounding and stratification analyses by cardio-cerebrovascular status, which all presented similar evidences.

Conclusions

High-frequency aspirin use is associated with the increased risk of lung cancer. Current smoker or people with age <76 years and bodyweight <80 kg should be more cautious to high-frequency aspirin use for lung cancer chemoprevention. This study provides a new insight for lung cancer chemoprevention.

Association between the use of aspirin and risk of lung cancer: results from pooled cohorts and Mendelian randomization analyses

PURPOSE

We aimed to elucidate the associations between aspirin use with risk of lung cancer, by conducting a meta-analysis and Mendelian randomization (MR) analyses from published Genome-Wide Association Studies (GWAS).

METHODS

Cohort studies, nested case-control studies, and randomized controlled trials (RCTs) investigating the impact of aspirin exposure and lung cancer incidence were included. Relative risk (RR) and its 95% confidence interval (CI) were evaluated in eligible studies. Subgroup analyses regarding gender, pathologic subtypes and smoking status were also executed. MR analyses were conducted using summary statistics obtained from two large consortia [Neale Lab and International Lung Cancer Consortium (ILCCO)] to assess the possible causal relationship of aspirin on lung cancer incidence.

RESULTS

Sixteen eligible studies involving 1,522,687 patients were included. The combined RR of aspirin use for the incidence of lung cancer was 0.95 (95% confidence interval (CI) 0.91-0.98). In subgroup meta-analyses, a significant protective effect was observed in squamous cell lung cancer (RR = 0.80; 95% CI 0.65-0.98). In terms of gender, the chemopreventive value was only observed among men (RR = 0.87; 95% CI 0.77-0.97). The MR risk analysis suggested a causal effect of aspirin on lung cancer incidence, with evidence of a decreased risk for overall lung cancer (OR = 0.042; 95% CI 0.003-0.564) and squamous cell lung cancer (OR = 0.002; 95% CI 1.21 × 10^-5-0.301).

CONCLUSION

Our study provided evidence for a causal protective effect of aspirin on the risk of lung cancer incidence among men, particularly on the squamous cell lung cancer risk.

Reconsidering the Role of Cyclooxygenase Inhibition in the Chemotherapeutic Value of NO-Releasing Aspirins for Lung Cancer

Nitric oxide-releasing aspirins (NO-aspirins) are aspirin derivatives that are safer than the parent drug in the gastrointestinal context and have shown superior cytotoxic effects in several cancer models. Despite the rationale for their design, the influence of nitric oxide (NO^•) on the effects of NO-aspirins has been queried. Moreover, different isomers exhibit varying antitumor activity, apparently related to their ability to release NO^•. Here, we investigated the effects and mode of action of NO-aspirins in non-small-cell lung cancer (NSCLC) cells, comparing two isomers, NCX4016 and NCX4040 (-meta and -para isomers, respectively). NCX4040 was more potent in decreasing NSCLC cell viability and migration and exhibited significant synergistic effects in combination with erlotinib (an epidermal growth factor receptor inhibitor) in erlotinib-resistant cells. We also studied the relationship among the effects of NO-aspirins, NO^• release, and PGE₂ levels. NCX4040 released more NO^• and significantly decreased PGE₂ synthesis relative to NCX4016; however, NO^• scavenger treatment reversed the antiproliferative effects of NCX4016, but not those of NCX4040. By contrast, misoprostol (a PGE₂ receptor agonist) significantly reversed the antiproliferative effect of NCX4040, but not those of NCX4016. Furthermore, misoprostol reversed the antimigratory effects of NCX4040. Overall, these results indicate that PGE₂ inhibition is important in the mode of action of NO-aspirins.

Nitric oxide-donating aspirin (NO-Aspirin) suppresses lung tumorigenesis in vitro and in vivo and these effects are associated with modulation of the EGFR signaling pathway

Although regular aspirin use has been shown to lower the risk of colorectal cancer, its efficacy against lung cancer is weak or inconsistent. Moreover, aspirin use increases the risk of ulcers and stomach bleeding. In this study, we determined the efficacy of nitric oxide-donating aspirin (NO-Aspirin), a safer form of aspirin in which the parent drug is linked to a nitric oxide-releasing moiety through a spacer, to suppress lung tumorigenesis. Under in vitro conditions, NO-Aspirin significantly reduced the proliferation and survival of tumorigenic bronchial cell line (1170) and non-small cell lung cancer (NSCLC) cell lines (A549, H1650, H1975 and HCC827) and colony formation by NSCLC cells at sub- or low micromolar concentrations (≤1 µM for 1170 cells and ≤6 µM for NSCLC cells) in a COX-2 independent manner. These effects were paralleled by suppression of phospho-epidermal growth factor receptor (EGFR), -STAT3, -Akt and -ERK and enhanced caspase 3 and PARP cleavage. Among NSCLC cells, EGFR mutant cells (H1650, H1975 and HCC827) were more sensitive than cells expressing wild-type EGFR (A549) and H1650 cells were the most sensitive. Moreover, NO-Aspirin sensitized H1650 and H1975 cells to the antiproliferative effects of erlotinib, a tyrosine kinase inhibitor. In in vivo studies using 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) + lipopolysaccharide (LPS)-induced model of lung tumorigenesis, NO-Aspirin significantly reduced the number and size of lung tumors, expression of phospho-EGFR and -Akt as well as the pro-inflammatory molecules TNF-α and interferon-gamma. Overall, these results indicate the potential of NO-Aspirin for the chemoprevention of lung cancer in high risk populations.

Racial and Ethnic Differences in the Relationship between Aspirin Use and Non-Small Cell Lung Cancer Risk and Survival

BACKGROUND

African Americans (AA) experience higher incidence and mortality of lung cancer as compared with European Americans (EA). Inflammation is associated with lung cancer, many aspects of which differ between AA and EA. We investigated whether use, frequency, and duration of the anti-inflammatory drug aspirin were associated with lung cancer risk and survival, separately among AA and EA populations.

METHODS

Using data from the Maryland Non-Small Cell Lung Cancer (NSCLC) Case-Control Study (1,220 cases [404 AA and 816 EA] and 1,634 controls [1,004 EA and 630 AA]), we estimated the adjusted odds ratios (OR) and hazard ratios (HR) with 95% confidence intervals (CI) of the associations between aspirin use and NSCLC risk and survival, respectively.

RESULTS

Any aspirin use (OR: 0.66; 95% CI, 0.49-0.89), daily use of ≥ 1 tablet (OR: 0.68; 95% CI, 0.50-0.90), and use for ≥ 3 years (OR: 0.61; 95% CI, 0.44-0.85) was associated with lower NSCLC risk only among men, even after adjustment for covariates including body mass index and global genetic ancestry. These variables were also associated with improved survival, but only among AA (HR: 0.64; 95% CI, 0.46-0.91; HR: 0.61; 95% CI, 0.42-0.90; and HR: 0.60; 95% CI, 0.39-0.92, respectively). Tylenol and other NSAIDs were either associated with elevated or no NSCLC risk.

CONCLUSIONS

Aspirin use is associated with lower risk of NSCLC among men and improved survival among AA.

IMPACT

Preventive regular aspirin use could be considered among men and AA.

Factors associated with lung cancer in COPD patients

Background

The risk of dying of lung cancer is up to eightfold higher in patients with COPD than in age- and gender-matched controls. The aim of this study was to investigate the factors associated with lung cancer in a large cohort of COPD patients from primary care centers.

Methods

To analyze whether age, gender, socioeconomic factors, comorbidity, and medication affect the risk of lung cancer in COPD, we used a COPD cohort of primary care patients. Data from primary care medical records and mandatory Swedish national registers were collected and linked in this population-based, retrospective observational registry study (NCT01146392).

Results

Of the total cohort, 19,894 patients were included in the study. Five hundred and ninety-four lung cancer cases were diagnosed, corresponding to 3.0% of the studied population. In a multivariate analysis, the risk of lung cancer was lower if the COPD patients had a concurrent asthma diagnosis (HR: 0.54, CI: 0.41–0.71), while the risk of lung cancer increased with increasing age. A decreased lung cancer risk was observed in an exposure-dependent manner in patients who were prescribed inhaled corticosteroids (HR: 0.52, CI: 0.37–0.73), while the opposite was found for the use of acetylsalicylic acid (HR: 1.58, CI: 1.15–2.16).

Conclusion

In this large population-based cohort, a concurrent asthma diagnosis and use of inhaled corticosteroids were independently related to decreased risk of lung cancer in COPD patients, while the use of acetylsalicylic acid was associated with an increased risk. The findings of the present study should be seen as hypothesis generating and need to be confirmed in prospective studies.

Meta-analysis of aspirin use and risk of lung cancer shows notable results

Aspirin is a promising agent for chemoprevention of lung cancer. We assessed the association of aspirin use and the development of lung cancer, with a focus on heterogeneity between studies. Databases were searched for relevant studies until September 2014. Studies evaluating the relationship of aspirin use and incidence of lung cancer were considered. Relative risks (RR) were extracted and a pooled estimate was calculated. Heterogeneity was assessed by the I measure, random-effects models, and finite-mixture models. Sources of heterogeneity were investigated using a meta-regression. A decreased risk of lung cancer was found including 20 studies [RR=0.87, 95% confidence interval (CI): 0.79-0.95] on the basis of a random-effects model. Strong heterogeneity was observed (τ=0.0258, I=74.4%). As a result, two subpopulations of studies were identified on the basis of a mixture model. The first subpopulation (42%) has an average RR of 0.64. The remaining subpopulation (58%) shows an RR of 1.04. Different results were found for case-control (RR=0.74, 95% CI: 0.60-0.90) and cohort studies (RR=0.99, 95% CI: 0.93-1.06) in a stratified analysis. In a subgroup analysis, use of aspirin was associated with a decreased risk of non-small-cell lung cancer in case-control studies (RR=0.74; 95% CI: 0.58-0.94). At first glance, our meta-analysis shows an average protective effect. A second glance indicates that there is strong heterogeneity. This leads to a subpopulation with considerable benefit and another subpopulation with no benefit. For further investigations, it is important to identify populations that benefit from aspirin use.

Cyclooxygenase 2: protein-protein interactions and posttranslational modifications

Numerous studies implicate the cyclooxygenase 2 (COX2) enzyme and COX2-derived prostanoids in various human diseases, and thus, much effort has been made to uncover the regulatory mechanisms of this enzyme. COX2 has been shown to be regulated at both the transcriptional and posttranscriptional levels, leading to the development of nonsteroidal anti-inflammatory drugs (NSAIDs) and selective COX2 inhibitors (COXIBs), which inhibit the COX2 enzyme through direct targeting. Recently, evidence of posttranslational regulation of COX2 enzymatic activity by s-nitrosylation, glycosylation, and phosphorylation has also been presented. Additionally, posttranslational regulators that actively downregulate COX2 expression by facilitating increased proteasome degradation of this enzyme have also been reported. Moreover, recent data identified proteins, located in close proximity to COX2 enzyme, that serve as posttranslational modulators of COX2 function, upregulating its enzymatic activity. While the precise mechanisms of the protein-protein interaction between COX2 and these regulatory proteins still need to be addressed, it is likely these interactions could regulate COX2 activity either as a result of conformational changes of the enzyme or by impacting subcellular localization of COX2 and thus affecting its interactions with regulatory proteins, which further modulate its activity. It is possible that posttranslational regulation of COX2 enzyme by such proteins could contribute to manifestation of different diseases. The uncovering of posttranslational regulation of COX2 enzyme will promote the development of more efficient therapeutic strategies of indirectly targeting the COX2 enzyme, as well as provide the basis for the generation of novel diagnostic tools as biomarkers of disease.

Phosphodiesterase 10A is overexpressed in lung tumor cells and inhibitors selectively suppress growth by blocking β-catenin and MAPK signaling

Phosphodiesterase 10A (PDE10) is a cyclic nucleotide (e.g. cGMP) degrading enzyme highly expressed in the brain striatum where it plays an important role in dopaminergic neurotransmission, but has limited expression and no known physiological function outside the central nervous system. Here we report that PDE10 mRNA and protein levels are strongly elevated in human non-small cell lung cancer cells and lung tumors compared with normal human airway epithelial cells and lung tissue, respectively. Genetic silencing of PDE10 or inhibition by small molecules such as PQ10 was found to selectively inhibit the growth and colony formation of lung tumor cells. PQ10 treatment of lung tumor cells rapidly increased intracellular cGMP levels and activated cGMP-dependent protein kinase (PKG) at concentrations that inhibit lung tumor cell growth. PQ10 also increased the phosphorylation of β-catenin and reduced its levels, which paralleled the suppression of cyclin D1 and survivin but preceded the activation of PARP and caspase cleavage. PQ10 also suppressed RAS-activated RAF/MAPK signaling within the same concentration range and treatment period as required for cGMP elevation and PKG activation. These results show that PDE10 is overexpressed during lung cancer development and essential for lung tumor cell growth in which inhibitors can selectively induce apoptosis by increasing intracellular cGMP levels and activating PKG to suppress oncogenic β-catenin and MAPK signaling.

Ibuprofen and fatal lung cancer: A brief report of the prospective results from the Third National Health and Nutrition Examination Survey (NHANES III)

Chronic inflammation appears to increase the risk of lung cancer and, reciprocally, agents that reduce inflammation have been found to reduce this risk. However, few prospective studies have assessed whether there exists an association between lung cancer and the use of non-steroidal anti-inflammatory drugs (NSAIDs). In the present study, the association between fatal lung cancer and NSAIDs was investigated using cohort data from the Third National Health and Nutrition Examination Study (NHANES III). Baseline data were collected on smoking, NSAID use and other lifestyle factors for 10,735 participants during 1988-1994, with cause-specific mortality status ascertained through probabilistic record matching based on the National Death Index until 2006. Cox proportional hazards regression models were conducted to estimate hazard ratios (HRs) and confidence intervals (CIs) for NSAID use and death from lung cancer, controlling for current smoking and other covariates. During the 18 years of follow-up, 269 participants succumbed to lung cancer, of whom 252 (93.6%) reported a history of cigarette smoking. Since all but 17 of the 269 fatal lung cancer cases occurred among current or former smokers, estimates of NSAID effects were ascertained from a sub-cohort of 5,882 individuals who reported a history of past or current cigarette smoking. Multivariate regression models revealed that regular use of ibuprofen resulted in a 48% reduced risk of lung cancer mortality (HR=0.52, 95% CI: 0.33-0.82, P<0.01). The main effects of other compounds tested, such as aspirin or acetaminophen, were not statistically significant. Our results suggest that high-risk subgroups of smokers may benefit from the regular use of specific NSAIDs, which may prove to be a useful strategy for lung cancer prevention.

Prognostic significance of cyclooxygenase-2 expression in patients with hepatocellular carcinoma: a meta-analysis

INTRODUCTION

Cyclooxygenase-2 (COX-2) is believed to be an important enzyme in the carcinogenesis of hepatocellular carcinoma (HCC). However, it is still controversial whether COX-2 expression can be regarded as a prognostic factor for HCC patients. We performed a systematic review and meta-analysis of studies assessing the clinical and prognostic significance of COX-2 expression in HCC.

MATERIAL AND METHODS

Identification and review of publications assessing clinical or prognostic significance of COX-2 expression in HCC until November 1, 2014. A meta-analysis was performed to clarify the association between COX-2 expression and clinical outcomes.

RESULTS

A total of 11 publications met the criteria and included 943 cases. Analysis of these data showed that COX-2 expression was not significantly correlated with capsular formation (OR = 0.84, 95% confidence interval (CI): 0.46-1.55, p = 0.58), tumor TNM stage (OR = 0.73, 95% CI: 0.23-2.33, p = 0.59), vascular invasion (OR = 1.04, 95% CI: 0.25-4.35, p = 0.96), tumor size (OR = 0.78, 95% CI: 0.21-2.86, p = 0.71), or tumor differentiation degree (OR = 1.08, 95% CI: 0.42-2.79, p = 0.87). However, in the identified studies, COX-2 expression was strongly associated with high alpha-fetoprotein level (OR = 1.83, 95% CI: 1.01-3.33, p = 0.05), HBsAg status (OR = 1.85, 95% CI: 1.13-3.03, p = 0.01), decreased overall survival (relative risk (RR): 1.54, 95% CI: 1.18-2.02, p = 0.001) and decreased disease-free survival (RR = 1.49, 95% CI: 1.22-1.81, p < 0.001).

CONCLUSIONS

This meta-analysis shows that COX-2 expression in HCC is associated with decreased overall and disease-free survival and thus marks a worse prognosis. Nevertheless, more large sample and well-designed studies are warranted to confirm this finding.

Platelets and cancer: a casual or causal relationship: revisited

Human platelets arise as subcellular fragments of megakaryocytes in bone marrow. The physiologic demand, presence of disease such as cancer, or drug effects can regulate the production circulating platelets. Platelet biology is essential to hemostasis, vascular integrity, angiogenesis, inflammation, innate immunity, wound healing, and cancer biology. The most critical biological platelet response is serving as "First Responders" during the wounding process. The exposure of extracellular matrix proteins and intracellular components occurs after wounding. Numerous platelet receptors recognize matrix proteins that trigger platelet activation, adhesion, aggregation, and stabilization. Once activated, platelets change shape and degranulate to release growth factors and bioactive lipids into the blood stream. This cyclic process recruits and aggregates platelets along with thrombogenesis. This process facilitates wound closure or can recognize circulating pathologic bodies. Cancer cell entry into the blood stream triggers platelet-mediated recognition and is amplified by cell surface receptors, cellular products, extracellular factors, and immune cells. In some cases, these interactions suppress immune recognition and elimination of cancer cells or promote arrest at the endothelium, or entrapment in the microvasculature, and survival. This supports survival and spread of cancer cells and the establishment of secondary lesions to serve as important targets for prevention and therapy.

The impact of comorbidity on cancer survival: a review

Background

A number of studies have shown poorer survival among cancer patients with comorbidity. Several mechanisms may underlie this finding. In this review we summarize the current literature on the association between patient comorbidity and cancer prognosis. Prognostic factors examined include tumor biology, diagnosis, treatment, clinical quality, and adherence.

Methods

All English-language articles published during 2002–2012 on the association between comorbidity and survival among patients with colon cancer, breast cancer, and lung cancer were identified from PubMed, MEDLINE and Embase. Titles and abstracts were reviewed to identify eligible studies and their main results were then extracted.

Results

Our search yielded more than 2,500 articles related to comorbidity and cancer, but few investigated the prognostic impact of comorbidity as a primary aim. Most studies found that cancer patients with comorbidity had poorer survival than those without comorbidity, with 5-year mortality hazard ratios ranging from 1.1 to 5.8. Few studies examined the influence of specific chronic conditions. In general, comorbidity does not appear to be associated with more aggressive types of cancer or other differences in tumor biology. Presence of specific severe comorbidities or psychiatric disorders were found to be associated with delayed cancer diagnosis in some studies, while chronic diseases requiring regular medical visits were associated with earlier cancer detection in others. Another finding was that patients with comorbidity do not receive standard cancer treatments such as surgery, chemotherapy, and radiation therapy as often as patients without comorbidity, and their chance of completing a course of cancer treatment is lower. Postoperative complications and mortality are higher in patients with comorbidity. It is unclear from the literature whether the apparent undertreatment reflects appropriate consideration of greater toxicity risk, poorer clinical quality, patient preferences, or poor adherence among patients with comorbidity.

Conclusion

Despite increasing recognition of the importance of comorbid illnesses among cancer patients, major challenges remain. Both treatment effectiveness and compliance appear compromised among cancer patients with comorbidity. Data on clinical quality is limited.

Inhaled corticosteroid use and risks of lung cancer and laryngeal cancer

BACKGROUND

Chronic inflammation has been implicated in the pathogenesis of several cancers, including lung and laryngeal cancer. The objective of the study is to elucidate the association between ICS use and diagnosis of lung and laryngeal cancer.

METHODS

A nested case-control study based on the Korean national claims database included new adult users of inhaled medications between January 1, 2007, and December 31, 2010. Patients diagnosed with lung cancer or laryngeal cancer after enrollment were identified as cases and up to five control individuals matched for age, sex, diagnosis of asthma or COPD, Charlson Comorbidity Index scores, number of health care visits, and initiation date were selected.

RESULTS

From the 792,687 eligible cohort, 9177 individuals diagnosed with lung cancer were matched with 37,048 controls. Additionally, 408 laryngeal cancer patients and 1651 controls were matched. ICS use was associated with a decreased rate of lung cancer diagnosis [adjusted odds ratio (aOR), 0.79; 95% confidence interval (CI), 0.69-0.90]. The inverse association between ICS use and lung cancer risk was dose dependent (P < 0.0001 for the trend). However, no reduction in the risk of laryngeal cancer among ICS users was identified (aOR, 1.06; 95% CI, 0.62-1.18).

CONCLUSION

The use of ICS is associated with a reduced risk of lung cancer but not of laryngeal cancer.

A novel sulindac derivative inhibits lung adenocarcinoma cell growth through suppression of Akt/mTOR signaling and induction of autophagy

Nonsteroidal anti-inflammatory drugs such as sulindac sulfide have shown promising antineoplastic activity in multiple tumor types, but toxicities resulting from COX inhibition limit their use in cancer therapy. We recently described a N,N-dimethylethyl amine derivative of sulindac sulfide, sulindac sulfide amide (SSA), that does not inhibit COX-1 or -2, yet displays potent tumor cell growth-inhibitory activity. Here, we studied the basis for the growth-inhibitory effects of SSA on human lung adenocarcinoma cell lines. SSA potently inhibited the growth of lung tumor cells with IC50 values of 2 to 5 μmol/L compared with 44 to 52 μmol/L for sulindac sulfide. SSA also suppressed DNA synthesis and caused a G0-G1 cell-cycle arrest. SSA-induced cell death was associated with characteristics of autophagy, but significant caspase activation or PARP cleavage was not observed after treatment at its IC50 value. siRNA knockdown of Atg7 attenuated SSA-induced autophagy and cell death, whereas pan-caspase inhibitor ZVAD was not able to rescue viability. SSA treatment also inhibited Akt/mTOR signaling and the expression of downstream proteins that are regulated by this pathway. Overexpression of a constitutively active form of Akt was able to reduce autophagy markers and confer resistance to SSA-induced cell death. Our findings provide evidence that SSA inhibits lung tumor cell growth by a mechanism involving autophagy induction through the suppression of Akt/mTOR signaling. This unique mechanism of action, along with its increased potency and lack of COX inhibition, supports the development of SSA or related analogs for the prevention and/or treatment of lung cancer.

Prediagnostic nonsteroidal anti-inflammatory drug use and lung cancer survival in the VITAL study

INTRODUCTION

Inflammation is important for lung oncogenesis. Use of nonsteroidal anti-inflammatory drugs (NSAIDs) has been shown to improve colorectal cancer survival. However, few studies have examined the association in lung cancer patients.

METHODS

The VITamins And Lifestyle (VITAL) cohort includes Washington State residents, aged 50 to 76 years, who completed a baseline questionnaire between 2000 and 2002. Participants responded on the frequency and duration of use of individual NSAIDs in the previous 10 years. Subjects of this study were 785 members of the cohort, who were identified with incident lung cancer from baseline through 2007 through linkage to a population-based cancer registry. Participants were followed for lung cancer death through linkage to state records of death through 2009. Adjusted proportional hazards models estimated hazard ratios (HR) and 95% confidence intervals (CI) for the association between NSAIDs and lung cancer death.

RESULTS

Five hundred and twenty-two participants (66%) died from lung cancer. Relative to nonuse, high (≥ 4 days/week and ≥ 4 years) prediagnostic use of regular-strength or low-dose aspirin (HR 0.99, 95% CI: 0.74-1.33 and HR 0.89, 95% CI: 0.67-1.17, respectively) or total nonaspirin NSAIDs (HR 1.20, 95% CI: 0.79-1.83) did not reduce lung cancer death. However, high use of ibuprofen was associated with a 62% increased risk of lung cancer death (HR 1.62, 95% CI: 1.01-2.58).

CONCLUSIONS

Long-term, prediagnostic NSAID use does not improve lung cancer survival overall. Use of ibuprofen may reduce survival from lung cancer. Our results underscore the need for further study of the mechanisms of action for individual NSAIDs with regard to cancer survival.

Celecoxib enhances the efficacy of 15-hydroxyprostaglandin dehydrogenase gene therapy in treating murine breast cancer

PURPOSE

The overexpression of 15-hydroxyprostaglandin dehydrogenase (15-PGDH) has been proved to inhibit tumor growth and metastasis through degradation of prostaglandin E2 (PGE2), which is often overexpressed in various cancers and accelerates tumor progression. Cyclooxygenase-2 (COX-2), a synthase of PGE2, actively produces much PGE2 to counteract the 15-PGDH-induced antitumor efficacy. Here, we investigated the combinational effect by using pcDNA3.1(+) encoding mouse 15-PGDH gene therapy and celecoxib, a COX-2 inhibitor, in mouse breast cancers.

METHODS

Mice bearing 4T1 were treated with short-term administration of the COX-2 inhibitor celecoxib (40 mg/kg/day) plus liposome-encapsulated mouse 15-PGDH in order to determine their synergistic antitumor activity in vivo. And the possible mechanisms were investigated.

RESULTS

We observed that the combination treatment of 15-PGDH and celecoxib significantly inhibited tumor growth and lung metastases than monotherapy or controls. Moreover, the effect of combination treatment was associated with significant reduction of PGE2 in serum, which resulted from increased 15-PDGH and decreased COX-2 in tumor tissues. The tumor tissues in combination treatment presented more apoptotic cells and less microvessel density. Notably, the number of myeloid-derived suppressor cells in the spleen was also significantly decreased in the combination treatment than others.

CONCLUSIONS

Our findings suggested that celecoxib increased the antitumor activity of 15-PGDH by synergistically blocking PGE2 pathway, which might be a new feasible way for cancer therapy.

Non-steroidal anti-inflammatory drugs and small cell lung cancer risk in the VITAL study

Few studies have examined the association between non-steroidal anti-inflammatory drug (NSAID) use and risk of small cell lung cancer (SCLC); among them, findings are mixed. Recently, we found that use of NSAIDs was differentially associated with lung cancer risk by histology. Here, we examine, more comprehensively, the association between individual NSAIDs and SCLC risk. 75,546 residents of western Washington State, ages 50-76, completed a baseline questionnaire in 2000-2002 and reported on their use of individual NSAIDs over the past 10 years. NSAID use was categorized as non-users, low (<4 days/week or <4 years), and high (≥4 days/week and ≥4 years). 111 SCLC were identified through linkage to a population-based cancer registry. Multivariable-adjusted Cox proportional hazards models including strong adjustment for smoking were used to estimate hazard ratios (HR) and 95% confidence intervals (95% CI). Compared to non-use, high use of regular-strength aspirin was associated with an elevated risk of SCLC (HR 1.78, 95% CI: 1.05-3.02; P-trend=0.03). Findings for low-dose aspirin were elevated but did not reach statistical significance. Use of non-aspirin NSAIDs was not associated with SCLC risk. Our findings provide further indication of heterogeneity in the association between aspirin and lung cancer morphologies. Large, prospective studies with comprehensive assessments of NSAID use and smoking history and data on both men and women, are needed in order to better understand the association between use of aspirin and SCLC.

Aspirin and non-aspirin non-steroidal anti-inflammatory drug use and risk of lung cancer

There is evidence that aspirin and non-aspirin non-steroidal anti-inflammatory drug (NSAID) have anti-carcinogenic properties, but their effect on lung cancer, in particular in never-smokers, is unclear. Information on past or current use of anti-inflammatory medication was obtained in 398 Chinese female primary lung cancer cases and 814 controls in a hospital-based study in Singapore. 65% of cases and 88% of controls were never-smokers. Controls were excluded if they had been admitted for conditions associated with aspirin or NSAID use (n=174). Regular aspirin use (twice a week or more, for a month or more) was associated with a reduced risk of lung cancer (adjusted odds ratio [OR] 0.50, 95% confidence intervals [95%CI] 0.31-0.81 in non-smokers; OR 0.38, 95%CI 0.16-0.93 in smokers). Regular use of non-aspirin NSAID, paracetamol, steroid creams and steroid pills was uncommon and no association with lung cancer was detected. Our results suggest that aspirin consumption may reduce lung cancer risk in Asian women and are consistent with current understanding of the role of cyclooxygenase in lung carcinogenesis.

Non-steroidal anti-inflammatory drugs and cancer incidence by sex in the VITamins And Lifestyle (VITAL) cohort

PURPOSE

Use of non-steroidal anti-inflammatory drugs (NSAIDs) may reduce the incidence of several cancers. A recent meta-analysis of randomized trials of aspirin reported a reduction in cancer mortality; however, few studies have investigated whether aspirin or other NSAIDs reduce overall cancer risk.

METHODS

64,847 residents of western Washington State, aged 50-76, completed a baseline questionnaire in 2000-2002 and reported on their use of individual NSAIDs over the past 10 years. Behavior was categorized as non-use, low (<4 days/week or <4 years), and high (≥4 days/week and ≥4 years). Over 7 years of follow-up, 5,946 incident invasive cancer cases were identified. Multivariable proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI).

RESULTS

Relative to non-use, high 10-year use of regular-strength NSAIDs was inversely associated with total cancer risk in men (HR 0.88, 95% CI: 0.79-0.97) and not associated with risk in women (HR 1.10, 95% CI: 0.96-1.25; p interaction <0.01). Use of regular-strength NSAIDs was strongly and inversely associated with colorectal cancer risk in men and women, but differentially associated with sex-specific risk of shared cancer sites other than colorectal cancer (men: HR 0.83, 95% CI: 0.71-0.97; women: HR 1.18, 95% CI: 0.97-1.44; p interaction < 0.01).

CONCLUSIONS

Long-term use of NSAIDs was associated with a reduced risk of total cancer among men and colorectal cancer among both sexes. Our findings do not support NSAID use for overall cancer prevention among women. Additional high-quality studies with long-term follow-up for cancer among women are needed before a public health recommendation can be made.

Aspirin and NSAID use and lung cancer risk: a pooled analysis in the International Lung Cancer Consortium (ILCCO)

PURPOSE

To investigate the hypothesis that non-steroidal anti-inflammatory drugs (NSAIDs) lower lung cancer risk.

METHODS

We analysed pooled individual-level data from seven case-control and one cohort study in the International Lung Cancer Consortium (ILCCO). Relative risks for lung cancer associated with self-reported history of aspirin and other NSAID use were estimated within individual studies using logistic regression or proportional hazards models, adjusted for packyears of smoking, age, calendar period, ethnicity and education and were combined using random effects meta-analysis.

RESULTS

A total of 4,309 lung cancer cases (mean age at diagnosis 65 years, 45% adenocarcinoma and 22% squamous-cell carcinoma) and 58,301 non-cases/controls were included. Amongst controls, 34% had used NSAIDs in the past (81% of them used aspirin). After adjustment for negative confounding by smoking, ever-NSAID use (affirmative answer to the study-specific question on NSAID use) was associated with a 26% reduction (95% confidence interval 8 to 41%) in lung cancer risk in men, but not in women (3% increase (-11% to 30%)). In men, the association was stronger in current and former smokers, and for squamous-cell carcinoma than for adenocarcinomas, but there was no trend with duration of use. No differences were found in the effects on lung cancer risk of aspirin and non-aspirin NSAIDs.

CONCLUSIONS

Evidence from ILCCO suggests that NSAID use in men confers a modest protection for lung cancer, especially amongst ever-smokers. Additional investigation is needed regarding the possible effects of age, duration, dose and type of NSAID and whether effect modification by smoking status or sex exists.

Variants in inflammation genes are implicated in risk of lung cancer in never smokers exposed to second-hand smoke

Lung cancer in lifetime never smokers is distinct from that in smokers, but the role of separate or overlapping carcinogenic pathways has not been explored. We therefore evaluated a comprehensive panel of 11,737 single-nucleotide polymorphisms (SNP) in inflammatory-pathway genes in a discovery phase (451 lung cancer cases, 508 controls from Texas). SNPs that were significant were evaluated in a second external population (303 cases, 311 controls from the Mayo Clinic). An intronic SNP in the ACVR1B gene, rs12809597, was replicated with significance and restricted to those reporting adult exposure to environmental tobacco smoke. Another promising candidate was an SNP in NR4A1, although the replication OR did not achieve statistical significance. ACVR1B belongs to the TGFR-β superfamily, contributing to resolution of inflammation and initiation of airway remodeling. An inflammatory microenvironment (second-hand smoking, asthma, or hay fever) is necessary for risk from these gene variants to be expressed. These findings require further replication, followed by targeted resequencing, and functional validation.

Meta-analysis on the association between nonsteroidal anti-inflammatory drug use and lung cancer risk

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs), especially aspirin, have emerged as the most potential chemopreventive agents. However, epidemiologic studies reported a controversial association between NSAID use and lung cancer risk. We conducted a meta-analysis to summarize the evidence for such relationship.

METHODS

Eligible studies were identified by searching the electronic literature PubMed, Medline, Embase, and ScienceDirect databases for relevant reports and bibliographies. Studies were included if they designed as cohort study, case-control study, or clinical trial on the NSAID exposure and lung cancer with sufficient raw data to analyzes. Relative risk (RR) or odds ratio (OR) was used to evaluate the association between NSAIDs and lung cancer. Stratified analysis was also performed.

RESULTS

A total of 19 studies including 20,266 lung cancer cases met the inclusion criteria. To the effect of aspirin on lung cancer, the combined RR for cohort studies was 0.96 (95%confidence interval [CI]: 0.78-1.19) and OR for case-control studies was 0.87 (95%CI: 0.69-1.09). When restricted in exposure of aspirin use to 7 tablets per week, the OR was 0.80 (95%CI: 0.67-0.95). The summary risk estimates showed no significant association between non-aspirin NSAID or overall NSAID use and lung cancer risk.

CONCLUSIONS

Aspirin use with a dose of 7 tablets per week can significantly reduce lung cancer risk, whereas non-aspirin NSAIDs showed no chemopreventive value. Greater attention should be paid to identifying appropriate individuals for this new indication of aspirin and the optimal dose and duration as a chemopreventive agent.

Nonsteroidal anti-inflammatory drug and acetaminophen use and risk of adult myeloid leukemia

BACKGROUND

Little is known about the causes of adult leukemia. A few small studies have reported a reduced risk associated with regular use of nonsteroidal anti-inflammatory drugs (NSAID).

METHODS

In a population-based case-control study, we evaluated analgesic use among 670 newly diagnosed myeloid leukemia cases [including 420 acute myeloid leukemias (AML) and 186 chronic myeloid leukemias (CML)] and 701 controls aged 20 to 79 years. Prior use of aspirin, ibuprofen, acetaminophen, other NSAIDs, and COX-2 inhibitors was assessed and included frequency, duration, and quantity. ORs and 95% CIs were calculated using unconditional logistic regression adjusting for potential confounders.

RESULTS

Regular/extra strength aspirin use was inversely associated with myeloid leukemia in women (OR = 0.59, 95% CI = 0.37-0.93) but not in men (OR = 0.85, 95% CI = 0.58-1.24). In contrast, acetaminophen use was associated with an increased risk of myeloid leukemia in women only (OR = 1.60, 95% CI = 1.04-2.47). These relationships were stronger with increasing dose and duration. When stratified by leukemia type, aspirin use was inversely associated with AML and CML in women. No significant overall associations were found with ibuprofen or COX-2 inhibitors for either sex; however, a decreased risk was observed with other anti-inflammatory analgesic use for women with AML or CML (OR = 0.47, 95% CI = 0.22-0.99; OR = 0.31, 95% CI = 0.10-0.92, respectively).

CONCLUSIONS

Our results provide additional support for the chemopreventive benefits of NSAIDs, at least in women. Because leukemia ranks fifth in person-years of life lost due to malignancy, further investigation is warranted.

IMPACT

NSAIDs may reduce, whereas acetaminophen may increase, myeloid leukemia risk in women.

Use of glucosamine and chondroitin and lung cancer risk in the VITamins And Lifestyle (VITAL) cohort

OBJECTIVE

Inflammation plays an important role in lung carcinogenesis. Epidemiologic studies have reported inverse associations of non-steroidal anti-inflammatory drug (NSAID) use and lung cancer risk. Previously, we found that ever use of glucosamine and chondroitin, which have anti-inflammatory properties, were inversely associated with lung cancer risk. After an additional year of follow-up, we further examined the association including frequency/duration of use, interaction with factors associated with inflammation, and lung cancer histology.

METHODS

Participants were members of the VITamins And Lifestyle cohort. Adults, aged 50-76 years, who were residents of western Washington State, completed a baseline questionnaire in 2000-2002 (n = 76,904). Participants were queried on their use of glucosamine and chondroitin, over the 10 years prior to baseline, and categorized as nonuser, low use < 4 days/week or < 3 years, or high use ≥ 4 days/week and ≥ 3 years. Lung cancer cases (n = 808) were ascertained through linkage to the Surveillance, Epidemiology, and End Results cancer registry.

RESULTS

High 10-year use of glucosamine [hazard ratio (HR), 0.77; 95% CI: 0.56-1.07; p trend = 0.04] but not chondroitin was associated with a reduction in lung cancer risk. The association with glucosamine was limited to adenocarcinoma (HR, 0.49; 95% CI: 0.27-0.90; p trend <0.01) and was not modified by NSAID use or smoking status.

CONCLUSIONS

Our results for glucosamine use are similar to the prior human studies of NSAID use and lung cancer, both in magnitude and the limitation of the association to adenocarcinoma. Unlike NSAIDs, glucosamine has no known adverse effects. Although confirmatory studies are needed, glucosamine is an attractive candidate for lung cancer chemoprevention.

Aspirin use and risk for lung cancer: a meta-analysis

BACKGROUND

Aspirin has received increasing attention owing to its potential as a chemopreventive agent against lung cancer. Previous observational studies have reported inconsistent findings on this issue. We investigated the association between aspirin use and risk for lung cancer by conducting a meta-analysis.

PATIENTS AND METHODS

Relevant studies were identified by searching Medline, EMBASE, and Cochrane Library to December 2009. We also reviewed relevant bibliographies from the retrieved articles. Two authors independently extracted data and assessed study quality. Disagreements were resolved by consensus.

RESULTS

Fifteen studies (six case-control studies and nine prospective cohort studies) were included in the final meta-analysis. When all studies were pooled, the odds ratio (OR) of aspirin use for lung cancer risk was 0.86 [95% confidence interval (CI) 0.76-0.98]. In subgroup meta-analyses, there was no association between aspirin use and lung cancer risk among cohort studies (relative risk, 0.97; 95% CI 0.87-1.08), while there was a significant association among case-control studies (OR, 0.74; 95% CI 0.57-0.99). In a subgroup meta-analysis by quality of study methodology, a significant protective effect of aspirin use on lung cancer was observed only among eight low-quality studies (OR, 0.82; 95% CI 0.68-0.99), but not among seven high-quality studies (OR, 0.90; 95% CI 0.76-1.07).

CONCLUSIONS

Overall, the findings of this meta-analysis support that there was no association between aspirin use and lung cancer risk. Our findings should be confirmed in future prospective cohort studies or randomized, controlled trials.

Meta-analysis on the relationship between nonsteroidal anti-inflammatory drug use and gastric cancer

Although nonsteroidal anti-inflammatory drugs (NSAIDs), including aspirin, show chemopreventive effects on several types of cancer, their role in the development of gastric cancer remains controversial. The objective of this study is to assess the quantitative association between NSAIDs and gastric cancer by meta-analysis using both crude data and adjusted data. A search of Medline, Embase, Web of science, and citations from relevant articles was conducted for eligible articles published up to March 2009. A meta-analysis was developed. Pooled risk ratio and odds ratio with 95% confidence intervals were calculated, based on both crude and adjusted data from the selected studies and using random or fixed effects models based on heterogeneity analysis. Overall, 21 individual epidemiological studies (13 case-control studies with 29 560 participants and 8 cohort studies with 2 199 227 participants) were examined. The summary crude and adjusted risk ratios were 0.89 (0.83-0.97) and 0.81 (0.73-0.89) when the case-control and cohort studies were pooled, respectively. Significant protective effects of NSAIDs against gastric cancer appeared in all subgroups (study design, type of drug, site of cancer, and sample source), but only the site of cancer and sample source can substantially influence the estimate of effect. The chemopreventive effect of NSAIDs in gastric cancer was stronger based on the adjusted data than that based on crude data. Therefore, we conclude that NSAID use is associated with a decrease in the development of gastric cancer. The associations were more obvious after we adjusted for several risk factors that are known to contribute to the development of gastric cancer.

Methylation status and overexpression of COX-2 in Tunisian patients with ductal invasive breast carcinoma

Inflammation and hormonal signalling induce the cyclooxygenase-2 (COX-2) expression in solid tumours including breast cancer, which in turn affects cell proliferation, apoptosis and metastasis. The aim of this study was to investigate the expression of COX-2 and its association with clinical parameters, patient's survival, hormones receptors (oestrogen, progesterone), ERBB2 and TP53 expression in 83 cases of infiltrating ductal breast carcinomas. Moreover, the methylation status at the CpG islands of the COX-2 gene promoter was also explored in 70 specimens. We showed that tumours exhibiting moderate to intense COX-2 immunostaining were significantly more frequent in patients over 45 years old (p = 0.027). Moreover, a high level of COX-2 expression correlated with a shorter survival time (p log-rank = 0.04) and was an independent prognostic factor (p = 0.022; HR 6.4; 95% CI = 1.3-31.4). On the other hand, hypermethylation of the COX-2 gene promoter was observed in 27% of cases and strongly associated with smaller tumours (<5 cm, p = 0.011). Furthermore, patients with methylated COX-2 pattern have a better 4-year disease-free survival (p = 0.022) as well as a prolonged overall survival (p log-rank test = 0.034). In conclusion, we showed that high COX-2 expression was associated with reduced survival and was an independent prognostic factor. However, hypermethylation of the COX-2 promoter correlated with a better overall survival in Tunisian patients with breast carcinoma.

Cyclooxygenase-2 and cancer treatment: understanding the risk should be worth the reward

Targeting the prostaglandin (PG) pathway is potentially a critical intervention for the prevention and treatment of cancer. Central to PG biosynthesis are two isoforms of cyclooxygenase (COX 1 and 2), which produce prostaglandin H(2) (PGH(2)) from plasma membrane stores of fatty acids. COX-1 is constitutively expressed, whereas COX-2 is an inducible isoform upregulated in many cancers. Differences between COX-1 and COX-2 catalytic sites enabled development of selective inhibitors. Downstream of the COX enzymes, prostaglandin E(2) synthase converts available PGH(2) to prostaglandin E(2) (PGE(2)), which can stimulate cancer progression. Significant research efforts are helping identify more selective targets and fully elucidate the downstream targets of prostaglandin E(2)-mediated oncogenesis. Nonetheless, as a key rate-limiting control point of PG biosynthesis, COX-2 continues to be an important anticancer target. As we embark upon a new era of individualized medicine, a better understanding of the individual risk and/or benefit involved in COX-2 selective targeting is rapidly evolving. This review endeavors to summarize developments in our understanding of COX-2 and its downstream targets as vital areas of anticancer research and to provide the current status of an exciting aspect of molecular medicine.

Association between nonsteroidal anti-inflammatory drug use and cutaneous squamous cell carcinoma

OBJECTIVE

To examine the association between nonsteroidal anti-inflammatory drug (NSAID) use and cutaneous squamous cell carcinoma (SCC).

DESIGN

Retrospective case-control study.

SETTING

Kaiser Permanente Northern California (KPNC), a large population based-health maintenance organization.

PATIENTS

Random sample of 415 KPNC members diagnosed as having a pathologically verified SCC in 2004 and 415 age-, sex-, and race-matched controls with no history of skin cancer.

MAIN EXPOSURE MEASURE

Self-reported NSAID use in the 10 years prior to baseline. Use of NSAIDs was categorized based on type (any NSAIDs, aspirin, ibuprofen, and nonaspirin NSAIDs). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using conditional logistic regression to estimate the association of SCC with regular use, dose, and duration of exposure to the different NSAID types. Information on pharmacy-dispensed NSAIDs was also examined to assess its association with SCC risk. Models were adjusted for all ascertained SCC risk factors (fully adjusted model) and only those variables associated with both SCC risk and NSAID use (parsimonious model).

RESULTS

Fully adjusted analyses showed no statistically significant reduction in SCC risk with self-reported regular use of any NSAID (OR, 1.32; 95% CI, 0.92-1.89), aspirin (OR, 1.38; 95% CI, 0.96-1.97), ibuprofen (OR, 0.74; 95% CI, 0.46-1.19), or nonaspirin NSAIDs (OR, 0.84; 95% CI, 0.56-1.26). Analyses examining duration, dose, and variables combining duration and dose of NSAID exposure did not appreciably change results. An analysis using the parsimonious model showed similar results. The data on pharmacy-dispensed NSAIDs also showed no association with SCC risk.

CONCLUSION

Neither self-reported nor pharmacy-dispensed NSAID exposure was associated with cutaneous SCC risk.

Lung inflammation, injury, and proliferative response after repetitive particulate hexavalent chromium exposure

BACKGROUND

Chronic inflammation is implicated in the development of several human cancers, including lung cancer. Certain particulate hexavalent chromium [Cr(VI)] compounds are well-documented human respiratory carcinogens that release genotoxic soluble chromate and are associated with fibrosis, fibrosarcomas, adenocarcinomas, and squamous cell carcinomas of the lung. Despite this, little is known about the pathologic injury and immune responses after repetitive exposure to particulate chromates.

OBJECTIVES

In this study we investigated the lung injury, inflammation, proliferation, and survival signaling responses after repetitive exposure to particulate chromate.

METHODS

BALB/c mice were repetitively treated with particulate basic zinc chromate or saline using an intranasal exposure regimen. We assessed lungs for Cr(VI)-induced changes by bronchoalveolar lavage, histologic examination, and immunohistochemistry.

RESULTS

Single exposure to Cr(VI) resulted in inflammation of lung tissue that persists for up to 21 days. Repetitive Cr(VI) exposure induced a neutrophilic inflammatory airway response 24 hr after each treatment. Neutrophils were subsequently replaced by increasing numbers of macrophages by 5 days after treatment. Repetitive Cr(VI) exposure induced chronic peribronchial inflammation with alveolar and interstitial pneumonitis dominated by lymphocytes and macrophages. Moreover, chronic toxic mucosal injury was observed and accompanied by increased airway pro-matrix metalloprotease-9. Injury and inflammation correlated with airways becoming immunoreactive for phosphorylation of the survival signaling protein Akt and the proliferation marker Ki-67. We observed a reactive proliferative response in epithelial cells lining airways of chromate-exposed animals.

CONCLUSIONS

These data illustrate that repetitive exposure to particulate chromate induces chronic injury and an inflammatory microenvironment that may promote Cr(VI) carcinogenesis.

NSAID use and risk of leukaemia: a population-based case-control study

PURPOSE

The use of non-steroidal anti-inflammatory drugs (NSAIDs) is associated with a reduced risk of developing colorectal and lung cancer. Studies suggesting similar associations in leukaemia have been small and underpowered. We have conducted a large population-based case-control study to determine whether the use of NSAIDs is associated with a reduced risk of acute and chronic leukaemias, and whether their use has any impact on survival in these patients.

METHODS

We identified all the incident cases of leukaemia in 'The Health Improvement Network' (THIN) general practice dataset, along with at least four matched controls per case. We used conditional logistic regression to determine odds ratios for NSAID prescription rates and the risk of developing several leukaemia sub-types. We then used Cox regression to determine the association between NSAID prescription rate and risk of death in leukaemia. Hazard ratios were adjusted for gender, age at diagnosis, smoking status and Townsend Score.

RESULTS

The risk of leukaemia overall appears to increase marginally with increased use of NSAIDs prior to diagnosis. This is not seen when individual leukaemia sub-types are examined, however, except perhaps in CLL where patients who had received 2-5 prescriptions/year are 34% more likely to be diagnosed with CLL than those who had not had any NSAID prescriptions (O.R. 1.34, p = 0.03, 95% C.I. 1.02-1.74). There was no statistically significant association between exposure to NSAIDs prior to leukaemia diagnosis and survival.

CONCLUSION

The use of NSAIDs does not reduce the risk of developing leukaemia, nor do they improve survival.

Cytokine and cytokine receptor single-nucleotide polymorphisms predict risk for non-small cell lung cancer among women

Studies on the relationships between inflammatory pathway genes and lung cancer risk have not included African-Americans and have only included a handful of genes. In a population-based case-control study on 198 African-American and 744 Caucasian women, we examined the association between 70 cytokine and cytokine receptor single-nucleotide polymorphisms (SNPs) and risk of non-small cell lung cancer (NSCLC). Unconditional logistic regression was used to estimate odds ratios and 95% confidence intervals in a dominant model adjusting for major risk factors for lung cancer. Separate analyses were conducted by race and by smoking history and history of chronic obstructive pulmonary disease among Caucasians. Random forest analysis was conducted by race. On logistic regression analysis, IL6 (interleukin 6), IL7R, IL15, TNF (tumor necrosis factor), and IL10 SNP were associated with risk of non-small cell lung cancer among African-Americans; IL7R and IL10 SNPs were also associated with risk of lung cancer among Caucasians. Although random forest analysis showed IL7R and IL10 SNPs as being associated with risk for lung cancer among African-Americans, it also identified TNFRSF10A SNP as an important predictor. On random forest analysis, an IL1A SNP was identified as an important predictor of lung cancer among Caucasian women. Inflammatory SNPs differentially predicted risk for NSCLC according to race, as well as based on smoking history and history of chronic obstructive pulmonary disease among Caucasian women. Pathway analysis results are presented. Inflammatory pathway genotypes may serve to define a high risk group; further exploration of these genes in minority populations is warranted.

Association of nonsteroidal anti-inflammatory drugs with lung cancer: results from a large cohort study

BACKGROUND

Lung cancer is the most common cause of cancer-related mortality. Smoking cessation is crucial to decrease risk, but additional prevention modalities are needed. The use of nonsteroidal anti-inflammatory drugs (NSAID) may be promising.

METHODS

The study was a prospective cohort of 77,125 men and women, ages 50 to 76 years, from Washington state recruited in 2000 to 2002 (the VITamin And Lifestyle study). Lung cancer cases were identified through the Seattle-Puget Sound Surveillance, Epidemiology and End Results cancer registry during 5 years of follow-up. Hazard ratios (HR) associated with 10-year average use of total NSAIDs (excluding low-dose aspirin) and specific categories of NSAIDs were calculated for total incident lung cancer and specific morphologies.

RESULTS

A total of 665 lung cancer cases were identified. After adjusting for smoking, age, gender, and acetaminophen use, there was a borderline-significant inverse trend with total NSAID use [>4.2 d/wk for >10 years versus none: HR, 0.82; 95% confidence interval (95% CI), 0.64-1.04; P for trend = 0.05]. The association was strongest for adenocarcinoma (HR, 0.59; 95% CI, 0.37-0.94; P for trend = 0.01) and seemed to be limited to men (HR, 0.66; 95% CI, 0.47-0.92; P for trend = 0.01) and to long-term (> or =10 years) former smokers (HR, 0.65; 95% CI, 0.44-0.96; P for trend = 0.04). There were no appreciable differences by NSAID type.

CONCLUSIONS

Total NSAID use was associated with a small reduced risk of lung cancer, which was strongest for adenocarcinoma, men, and long-term former smokers. These findings are supported by known lung carcinogenesis mechanisms and suggest that NSAIDS may be useful for chemoprevention.

Lung injury, inflammation and Akt signaling following inhalation of particulate hexavalent chromium

Certain particulate hexavalent chromium [Cr(VI)] compounds are human respiratory carcinogens that release genotoxic soluble chromate, and are associated with fibrosis, fibrosarcomas, adenocarcinomas and squamous cell carcinomas of the lung. We postulate that inflammatory processes and mediators may contribute to the etiology of Cr(VI) carcinogenesis, however the immediate (0-24 h) pathologic injury and immune responses after exposure to particulate chromates have not been adequately investigated. Our aim was to determine the nature of the lung injury, inflammatory response, and survival signaling responses following intranasal exposure of BALB/c mice to particulate basic zinc chromate. Factors associated with lung injury, inflammation and survival signaling were measured in airway lavage fluid and in lung tissue. A single chromate exposure induced an acute immune response in the lung, characterized by a rapid and significant increase in IL-6 and GRO-alpha levels, an influx of neutrophils, and a decline in macrophages in lung airways. Histological examination of lung tissue in animals challenged with a single chromate exposure revealed an increase in bronchiolar cell apoptosis and mucosal injury. Furthermore, chromate exposure induced injury and inflammation that progressed to alveolar and interstitial pneumonitis. Finally, a single Cr(VI) challenge resulted in a rapid and persistent increase in the number of airways immunoreactive for phosphorylation of the survival signaling protein Akt, on serine 473. These data illustrate that chromate induces both survival signaling and an inflammatory response in the lung, which we postulate may contribute to early oncogenesis.

Review paper: the role of inflammation in mouse pulmonary neoplasia

Inflammation is a risk factor for the development of many types of neoplasia, including skin, colon, gastric, and mammary cancers, among others. Chronic pulmonary diseases, such as chronic bronchitis and asthma, predispose to lung neoplasia. We will review the mouse literature examining the role of inflammation in lung neoplasia, focusing specifically on genetic susceptibility, pharmacologic modulation of inflammatory pathways, and both transgenic and knockout mouse models used to assess pro- and anti-inflammatory pathways involved in lung neoplasia. Identification of molecular mechanisms that govern the association between inflammation and pulmonary neoplasia could provide novel preventive, diagnostic, and therapeutic strategies for a disease in which few biomarkers currently exist.

Inflammation in the development of lung cancer: epidemiological evidence

The lung is a site for repeated or chronic inflammatory insults. Epidemiologic research has provided evidence to support the hypothesis that tissue damage caused by inflammation can initiate or promote the development of lung cancer, possibly in conjunction with tobacco use. For example, some studies suggest an increased risk of lung cancer among persons with lung infections, such as tuberculosis, bacterial pneumonia, or inflammatory lung diseases. Elevated serum levels of C-reactive protein, an inflammation marker, are associated with heightened lung cancer risk. Recent studies also demonstrate increased lung cancer risk among immunosuppressed individuals infected with HIV. Other research indicates an association between genetic polymorphisms in the inflammation pathway, which might modulate the inflammatory response and lung cancer risk.

Regular adult aspirin use decreases the risk of non-small cell lung cancer among women

BACKGROUND

Prior studies indicate that use of aspirin or other nonsteroidal anti-inflammatory drugs (NSAID) is associated with a decreased risk of non-small cell lung cancer (NSCLC); however, results have been contradictory in part because of variation in study design. Few studies have examined the use of aspirin or other NSAIDs on risk of NSCLC in women.

METHODS

Through a case-control study of African American and Caucasian women with and without NSCLC, we examined the relationship between use of aspirin, NSAIDs, and acetaminophen and risk of NSCLC. Risk was estimated by calculating odds ratios and 95% confidence intervals for ever/never use, duration of use, and duration of use category (never, 1-5 years, >5 years) after adjusting for major risk factors for lung cancer. Risk estimates were stratified by race, age, smoking history, and body mass index.

RESULTS

Every use of adult-strength aspirin was associated with a significant reduction in risk of NSCLC (odds ratio, 0.66; 95% confidence interval, 0.46-0.94). Additionally, there was a significant trend toward a reduced risk of NSCLC in adult-strength aspirin users with increasing duration of use (P(trend) = 0.02). In stratified analyses, aspirin use was associated with a significantly reduced risk of lung cancer among Caucasians and 55- to 64-year-olds. Baby aspirin and NSAID use was associated with a significant reduction in risk of NSCLC only among 65- to 74-year-olds.

CONCLUSION

Our results suggest that long-term use of adult-strength aspirin may reduce the risk of NSCLC in women.

Polymorphisms in genes involved in the inflammatory response and interaction with NSAID use or smoking in relation to lung cancer risk in a prospective study

Lung cancer risk was investigated in relation to single nucleotide polymorphisms in genes involved in the inflammatory response. The aim was to see if polymorphisms modifying the inflammatory response are associated with risk of lung cancer and if there were interactions between the same polymorphism and factors, which modify an inflammatory response, such as smoking status, duration, and intensity, and use of NSAID. The functional SNPs IL-1B T-31C, IL6 G-174C, IL8 T-251A, IL10 C-592T, COX2 C8473T, COX2 A-1195G and PPARgamma2 Pro(12)Ala were included. A case-cohort study including 428 lung cancer cases and a sub-cohort of 800 persons was nested within a population-based prospective study of 57,053 individuals. Variant allele carriers of IL-1B T-31C were at increased risk of lung cancer (IRR=1.51, 95% CI=1.08-2.12). There was interaction between the polymorphism COX-2 T8473C and smoking status. Thus, non-smoking variant allele carriers were at 5.75-fold (95% CI=1.25-26.43) higher risk of lung cancer than for homozygous wild type allele carriers. Lung cancer risk was similar for all genotype carriers among past and current smokers. There were, however, very few non-smoking lung cancer cases. There was interaction between IL-1B T-31C, COX-2 A-1195G and PPARgamma2 Pro(12)Ala and NSAID use in relation to lung cancer risk. For the two latter, NSAID use was only associated with a lower cancer risk among homozygous wild type allele carriers. p for interaction was 3 x 10(-6) for COX-2 A-1195G and 9 x 10(-5) for PPARgamma2 Pro(12)Ala. The results suggest that NSAID use may modify risk of lung cancer differently depending on the genotype.

Aspirin and lung cancer risk in a cohort study of women: dosage, duration and latency

Aspirin may reduce the risk of cancer at some sites but its effect at the lung is unclear. We prospectively examined associations between aspirin use and risk of lung cancer in 109,348 women in the Nurses' Health study from 1980 to 2004. During this time, 1,360 lung cancers were documented in participants 36-82 years of age. Aspirin use and smoking were assessed every 2 years. Risk of lung cancer was a non-significant 16% lower for regular aspirin users of one or two tablets per week and a significant 55% higher for users of 15 or more tablets per week compared with women who never regularly used aspirin. Results were similar when limited to never smokers. For both the low and high quantity aspirin users, risk of lung cancer did not decline or increase with longer durations of use, and associations attenuated as the latency period between aspirin assessment and lung cancer diagnosis was lengthened. Our findings, together with those from previous clinical trials and prospective studies, do not provide consistent evidence that aspirin influences the development of lung cancer and further investigation is required with adjustment for smoking.

Elevated expression of cyclooxygenase-2 is a negative prognostic factor for overall survival in intrahepatic cholangiocarcinoma

The production of prostaglandins is regulated by cyclooxygenases (COXs), which also have a role in tumour development and progression in various human malignancies, including cholangiocarcinoma. Limited information is available of the correlation of COX-2 protein expression and prognosis in intrahepatic cholangiocarcinoma (ICC). The aim of the present study was to determine the clinical significance of COX-2 expression in ICC. In addition the correlation of COX-2 expression and apoptosis/proliferation was analysed. COX-2 expression was determined immunohistochemically in 62 resected ICCs. Proliferation was assessed using Ki67-immunohistochemistry, and apoptosis was measured with the TdT-mediated dUTP nick-end-labelling technique. COX-2 was identified as an independent prognostic factor (P = 0.028) in resected ICC by survival analysis. High levels of COX-2 expression were found to be associated both with reduced apoptosis and increased proliferation of tumour cells. This study demonstrates the independent prognostic value of the COX-2 expression in resected ICC, thus, offering a potential additional adjuvant therapeutic approach with COX-2 inhibitors.

Systematic Evaluation of Genetic Variants in the Inflammation Pathway and Risk of Lung Cancer

Inflammatory responses to environmental exposures, such as tobacco smoke, may play a role in lung carcinogenesis. To test this hypothesis, we studied genetic polymorphisms in the inflammation pathway in relation to lung cancer risk. We evaluated a panel of 59 single nucleotide polymorphisms (SNP) in 37 inflammation-related genes among non-Hispanic Caucasian lung cancer cases (N=1,553) and controls (N=1,730) from Houston, Texas. Logistic regression was used to assess associations with lung cancer under a dominant genetic model adjusted for sex, age, and smoking. Haplotypes were estimated with the expectation-maximization algorithm. False-positive report probabilities (FPRP) were calculated for significant associations. Interleukin 1 beta (IL1B) C3954T was associated with lung cancer [odds ratio (OR), 1.27; 95% confidence interval (95% CI), 1.10-1.47; FPRP 0.148]. Two IL1A SNPs (C-889T and Ala(114)Ser) were also related to lung cancer (OR, 1.18-1.22), although FPRPs were higher. One IL1A-IL1B haplotype, containing only the IL1B 3954T allele, was associated with elevated lung cancer risk (OR, 1.80; 95% CI, 1.24-2.61). These associations were stronger in heavy smokers, particularly for IL1B C3954T (OR, 1.59; 95% CI, 1.28-1.97; FPRP 0.004). Lung cancer risk was unrelated to polymorphisms in IL1 receptor or antagonist genes. Associations with lung cancer were also seen for SNPs in granulocyte macrophage colony stimulating factor and peroxisome proliferator-activated factor-delta, but FPRPs were high. IL1A and IL1B polymorphisms are associated with increased lung cancer risk, especially among heavy smokers. IL1A and IL1B are critical signals in initiating inflammation. Our results suggest that a dysregulated inflammatory response to tobacco-induced lung damage promotes carcinogenesis.

A large cohort study of long-term daily use of adult-strength aspirin and cancer incidence

BACKGROUND

Epidemiologic evidence indicates that aspirin use is associated with reduced risks of colon cancer and possibly several other cancers, including prostate and breast cancers. Recent results from the Women's Health Study randomized trial indicate that long-term use of low-dose aspirin (100 mg every other day) does not substantially reduce cancer risk. However, the potential effect of long-term daily use of higher doses of aspirin on cancer incidence remains uncertain.

METHODS

We examined associations between long-term daily use of adult-strength aspirin (> or = 325 mg/day) and both overall cancer incidence and incidence of 10 types of cancer among 69,810 men and 76,303 women participating in the Cancer Prevention Study II Nutrition Cohort, a relatively elderly population. Aspirin use was reported at enrollment in 1992-1993 and updated in 1997, 1999, and 2001. Multivariable Cox proportional hazards regression was used to calculate rate ratios (RRs).

RESULTS

During follow-up through June 2003, 10,931 men and 7196 women were diagnosed with cancer. Long-term (> or = 5 years) daily use of adult-strength aspirin, compared with no use, was associated with lower overall cancer incidence in men (multivariable-adjusted RR = 0.84, 95% confidence interval [CI] = 0.76 to 0.93) and non-statistically significantly lower overall cancer incidence in women (multivariable-adjusted RR = 0.86, 95% CI = 0.73 to 1.03). Overall cancer incidence per 100,000 person-years (standardized to the age distributions of men and women in the study) with long-term daily aspirin use and no aspirin use was 1858 and 2163, respectively, among men and 1083 and 1169, respectively, among women. Long-term daily aspirin use was associated with lower incidence of colorectal cancer (RR = 0.68, 95% CI = 0.52 to 0.90 among men and women combined) and prostate cancer (RR = 0.81, 95% CI = 0.70 to 0.94) and a non-statistically significant lower risk of female breast cancer (RR = 0.83, 95% CI = 0.63 to 1.10).

CONCLUSIONS

Long-term daily use of adult-strength aspirin may be associated with modestly reduced overall cancer incidence in populations among whom colorectal, prostate, and breast cancers are common.

Nonsteroidal anti-inflammatory drugs and lung cancer risk: a population-based case control study

BACKGROUND

It remains unknown whether nonsteroidal anti-inflammatory drugs (NSAIDs) confer a protective effect against lung cancer development. We examined the relationship between NSAID exposure and subsequent lung cancer development in a large statewide, population-based cohort.

DESIGN

Nested case-control study in the Tennessee Medicaid population from 1990 to 2000.

METHODS

Lung cancer cases were identified using a statewide computerized claims database. Each time a case was identified, age- and sex-matched controls were randomly selected from the available source population. A detailed pharmacy database quantified nonsteroidal anti-inflammatory drug (NSAID) exposure during the 5 years before cancer diagnosis, and conditional logistic regression was used to examine the relationship between NSAID exposure and lung cancer development. Identical analyses were repeated in a subpopulation of high-risk individuals with chronic obstructive pulmonary disease (COPD).

RESULTS

303,399 persons were enrolled in the study population. During 1.9 million person-years of follow-up (median 6.3 years per person), 3,370 lung cancer cases were identified. Among those ever using NSAIDs, the adjusted odds ratio of developing lung cancer was 1.03 (95% confidence interval: 0.94-1.12). Among those using >24 months of NSAIDs in the 5 years before lung cancer diagnosis, the adjusted odds ratio for lung cancer was 0.96 (95% confidence interval: 0.82-1.11), and no protective effect was demonstrated in any NSAID exposure stratum. Similarly, among the 2519 high-risk individuals with chronic obstructive pulmonary disease, no significant protective effect from NSAIDs was noted.

CONCLUSION

This large statewide, population-based study did not demonstrate a protective effect of NSAIDs on lung cancer development in either the general or high-risk chronic obstructive pulmonary disease populations.