Cancers often arise as the end stage of inflammation in adults, but not in children. As such there is a complex interplay between host immune cells during neoplastic development, with both an ability to promote cancer as well as limit or eliminate it, most often complicit with the host. In humans, defining inflammation and the presence of inflammatory cells within or surrounding the tumor is a critical aspect of modern pathology. Groups defining staging for neoplasms are strongly encouraged to assess and incorporate measures of the presence of apoptosis, autophagy, and necrosis as well as the nature and quality of the immune infiltrate. Both environmental as well as genetic factors enhance the risk of cigarette smoking, H. pylori, hepatitis B/C, human papilloma virus, solar irradiation, asbestos, pancreatitis, or other causes of chronic inflammation. Identifying suitable genetic polymorphisms in cytokines, cytokine receptors, and Toll-like receptors among other immune response genes is also seen as high value as genomic sequencing becomes less expensive. Animal models which incorporate and assess not only the genetic anlagen but also the inflammatory cells and the presence of microbial pathogen [PAMPs] and damage associated molecular pattern molecules [DAMPs] are necessary. Identifying micro-RNAs involved in regulating the response to damage or injury are seen as highly promising. Although no therapeutic strategies to prevent or treat cancers based on insights into inflammatory pathways are currently approved for the common epithelial malignancies, there remains substantial interest in agents targeting COX2 or PPARγ, ethyl pyruvate, as well as steroids and several novel agents on the horizon.

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There are no established chemopreventive agents for lung cancer, the leading cause of cancer death in the United States. Prostacyclin levels are low in lung cancer and supplementation prevents lung cancer in preclinical models. We carried out a multicenter double-blind, randomized, phase II placebo-controlled trial of oral iloprost in current or former smokers with sputum cytologic atypia or endobronchial dysplasia. Bronchoscopy was performed at study entry and after completion of six months of therapy. Within each subject, the results were calculated by using the average score of all biopsies (Avg), the worst biopsy score (Max), and the dysplasia index (DI). Change in Avg was the primary end point, evaluated in all subjects, as well as in current and former smokers. The accrual goal of 152 subjects was reached and 125 completed both bronchoscopies (60/75 iloprost, 65/77 placebo). Treatment groups were well matched for age, tobacco exposure, and baseline histology. Baseline histology was significantly worse for current smokers (Avg 3.0) than former smokers (Avg 2.1). When compared with placebo, former smokers receiving oral iloprost exhibited a significantly greater improvement in Avg (0.41 units better, P = 0.010), in Max (1.10 units better, P = 0.002), and in DI (12.45%, P = 0.006). No histologic improvement occurred in current smokers. Oral iloprost significantly improves endobronchial histology in former smokers and deserves further study to determine if it can prevent the development of lung cancer.

Elevated tumor cyclooxygenase (COX)-2 activity plays a multifaceted role in non-small cell lung cancer (NSCLC). To elucidate the role of COX-2 in the in vitro and in vivo expression of two known NSCLC angiogenic peptides, CXC ligand (CXCL) 8 and CXCL5, we studied two COX-2 gene-modified NSCLC cell lines, A549 and H157. COX-2 overexpression enhanced the in vitro expression of both CXCL8 and CXCL5. In contrast, specific COX-2 inhibition decreased the production of both peptides as well as nuclear translocation of nuclear factor B. In a severe combined immunodeficient mouse model of human NSCLC, the enhanced tumor growth of COX-2-overexpressing tumors was inhibited by neutralizing anti-CXCL5 and anti-CXCL8 antisera. We conclude that COX-2 contributes to the progression of NSCLC tumorigenesis by enhancing the expression of angiogenic chemokines CXCL8 and CXCL5.

Lung carcinogenesis is a complex process involving the acquisition of genetic mutations that confer cancer development and the malignant phenotype, and is critically linked to apoptosis resistance, unregulated proliferation, invasion, metastasis, and angiogenesis. Epithelial mesenchymal transition (EMT) in cancer is an unregulated process in a host environment with deregulated inflammatory response that impairs cell-mediated immunity and permits cancer progression. Given the immunosuppressive tumor environment, strategies to reverse these events by stimulating host immune responses are an important area of investigation. Cyclooxygenase 2 (COX-2) and its downstream signaling pathways are potential targets for lung cancer chemoprevention and therapy. Clinical trials are underway to evaluate COX-2 inhibitors as adjuvants to chemotherapy in patients with lung cancer and to determine efficacy in prevention of bronchogenic carcinoma. The understanding of molecular mechanisms involved in inflammation and lung carcinogenesis provide insight for new drug development that target reversible, non-mutational events in the chemoprevention and treatment of lung cancer.

Emphysema results from progressive destruction of alveolar septae and was considered irreversible until all-trans-retinoic acid (ATRA) was shown to reverse anatomic and physiologic signs of emphysema in a rat model. To evaluate the feasibility of ATRA as a clinical therapy, 20 patients with severe emphysema were enrolled into a randomized, double-blind, placebo-controlled pilot study. Participants included 16 male and 4 female former smokers, two with alpha(1)-antitrypsin deficiency. Patients were treated with either 3 mo of ATRA (50 mg/m(2)/d) or 3 mo of placebo, followed by a 3-mo crossover phase. Plasma drug levels were followed and outcome measures included serial pulmonary function tests, blood gases, lung compliance, computed tomography (CT) imaging, and quality of life questionnaires. In general, treatment was well tolerated and associated with only mild side effects including skin changes, transient headache, hyperlipidemia, transaminites, and musculoskeletal pains. Plasma drug levels varied considerably between subjects and decreased significantly over time in 35% of the participants. Physiologic and CT measurements did not change appreciably in response to therapy. We conclude that ATRA is well tolerated in patients with emphysema, and trials evaluating higher doses, longer treatment, or different dosing schedules are feasible.

BACKGROUND Laboratory studies suggest that flavonoids are antimutagenic and anticarcinogenic. To investigate the associations between commonly consumed flavonoid compounds and lung cancer, the authors conducted a population‐based case–control study of 558 lung cancer cases and a group of 837 controls. METHODS Dietary intakes of flavonoids were estimated by combining the intake frequency (collected by a food frequency questionnaire), portion size, and food composition data. Unconditional logistic regression analysis was used to estimate odds ratios (ORs) and 95% confidence limits (95% CLs) with an adjustment for potential confounders, including age, sex, race‐ethnicity, years of schooling, smoking status, pack‐years of tobacco smoking, and daily energy intake. RESULTS Lung cancer was associated inversely with the consumption of epicatechin (in 10 mg per day increment: OR, 0.64; 95% CL, 0.46–0.88), catechin (4 mg per day increment: OR, 0.49; 95% CL, 0.35–0.70), quercetin (9 mg per day increment: OR, 0.65; 95% CL, 0.44–0.95), and kaempferol (2 mg per day increment: OR, 0.68; 95% CL, 0.51–0.90) among tobacco smokers. There was little association between lung cancer and the flavonoid compounds mentioned above among nonsmokers. Regardless of smoking status, there was little association with total flavonoids: thearubigins, hesperetin, naringenin, and myricetin. In addition, consumption of vegetables, tea, and wine, all of which are rich sources of flavonoids, was associated inversely with lung cancer among tobacco smokers. CONCLUSIONS Certain flavonoid compounds, including epicatechin, catechin, quercetin, and kaempferol, were associated inversely with lung cancer among tobacco smokers, but not among nonsmokers. Further studies of these associations may be warranted. Cancer 2008. © 2008 American Cancer Society.

We investigated the effects of XPG His1104Asp polymorphism (rs17655) on the risk of lung cancer and squamous cell carcinomas of the oropharynx, larynx and esophagus (SCCOLE). This population-based case-control study involves 611 new cases of lung cancer, 601 new cases of oropharyngeal, laryngeal and esophageal cancers, and 1,040 cancer-free controls. The XPG polymorphism was assayed by PCR-RFLP method for 497 lung cancer cases, 443 cases of oropharyngeal, laryngeal and esophageal cancers and 912 controls. Binary and polytomous unconditional logistic regression models were fitted to assess the main effects and the effect modifications between the polymorphism and environmental exposures. With the adjustment for potential confounders, the XPG Asp1104Asp genotype was inversely associated with lung cancer (odds ratio [OR] 5 0.62, 95% confidence limits [CL] 5 0.38, 1.0) and SCCOLE (OR 5 0.47, 95% CL 5 0.27, 0.82), with the combined His1104His and His1104Asp genotypes as the referent. With subjects having genotype Asp1104Asp and no tobacco smoking exposure as the common referent, the ORs on lung cancer were 13 (95% CL 5 4.4, 37) for heavy tobacco smoking (>20 pack-years), 1.9 (95% CL 5 0.78, 4.5) for having at least one copy of 1104His, and 23 (95% CL 5 9.5, 56) for the joint effect, respectively. Compared to non-smokers with the Asp1104Asp genotype, the adjusted OR on SCCOLE for heavy smokers (>20 pack-years) having at least one copy of 1104His was 8.0 (95% CL 5 2.7, 24). Similarly, compared to non-drinkers with the Asp1104Asp genotype, the adjusted OR on SCCOLE for heavy drinkers (3 drinks/ day) with at least one copy of 1104His was 10 (95% CL 5 2.7, 38). In conclusion, our study suggests that the XPG Asp1104Asp genotype may be associated with decreased susceptibility to lung cancer and SCCOLE. ' 2005 Wiley-Liss, Inc.