Metformin exposure is associated with improved progression-free survival in diabetic patients after resection for early-stage non-small cell lung cancer.

OBJECTIVE: There are little clinical data assessing the antineoplastic effect of metformin in patients with non-small cell lung cancer. We hypothesized that in diabetic patients undergoing pulmonary resection for early-stage non-small cell lung cancer, metformin exposure is associated with improved survival. METHODS: An institutional database was used to identify patients with stage I or II non-small cell lung cancer who underwent pulmonary resection between 2004 and 2013. Patients were divided into 3 cohorts: type II diabetic patients with metformin exposure (cohort A, n = 81), type II diabetic patients without metformin exposure (cohort B, n = 57), and nondiabetic individuals (cohort C, n = 77). Univariate, multivariate, and propensity-matched analyses were performed to assess progression-free and overall survivals between groups. RESULTS: A total of 215 patients with stage I and II non-small cell lung cancer treated with surgical resection were identified for analysis with a median follow-up of 19.5 months. Patients in cohort A had lower T- and N-stage tumors than those in cohorts B or C. However, on multivariate analysis adjusting for age, gender, and T and N stage, progression-free survival was greater for cohort A than cohort B (hazard ratio [HR], 0.410; 95% confidence interval, 0.199-0.874; P = .022) or cohort C (HR, 0.415; 95% confidence interval, 0.201-0.887; P = .017). Likewise, when propensity-matched analyses were performed, cohort A demonstrated a trend toward improved progression-free survival compared with cohort B (P = .057; HR, 0.44; c-statistic = 0.832) and improved progression-free survival compared with cohort C (P = .02; HR, 0.41; c-statistic = 0.843). No differences were observed in overall survival. CONCLUSIONS: Metformin exposure in diabetic patients with early-stage non-small cell lung cancer may be associated with improved progression-free survival, but no effect was seen on overall survival. Further studies are warranted to evaluate if there is a therapeutic role for metformin in the treatment of non-small cell lung cancer.

Angiogenesis Biomarkers May Be Useful in the Management of Patients With Indeterminate Pulmonary Nodules.

BACKGROUND: Low-dose computed tomography (CT) lung cancer screening is known to have a high false positive rate. This study aims to survey biomarkers of angiogenesis for those capable of assigning clinical significance to indeterminate pulmonary nodules detected through CT imaging studies. METHODS: An institutional database and specimen repository was used to identify 193 patients with stage I non-small cell lung cancer (T1N0M0) and 110 patients with benign solitary pulmonary nodules detected by CT imaging studies. All specimens were evaluated in a blinded manner for 17 biomarkers of angiogenesis using multiplex immunoassays. Biomarker performance was calculated through the Mann-Whitney rank sum U test and a receiver operator characteristic analysis. These data were used to refine our previously reported multi-analyte classification panel, which was then externally validated against an independent patient cohort (n = 80). RESULTS: A total of 303 patients were screened for 17 biomarkers of angiogenesis. Median nodule size was 1.2 cm for benign cases and 1.8 cm for non-small cell lung cancer, whereas median smoking histories were 25 and 40 pack-years, respectively. Differences in serum concentrations of heparin-binding epidermal growth factor (HB-EGF), epidermal growth factor (EGF), vascular (V)EGF-A, VEGF-C, and VEGF-D were strongly significant (p ≤ 0.001) while follistatin, placental growth factor (PLGF), and bone morphogenic protein (BMP)-9 were significant (p ≤ 0.05) between patients with benign and malignant nodules. Our previously reported multi-analyte classification panel was refined to include interleukin (IL)-6, IL-10, IL-1 receptor antagonist (RA), tumor necrosis factor (TNF)-α, insulin-like growth factor binding protein (IGFBP)-5, IGFBP-4, IGF-2, stromal cell-derived factor (SDF)-1(α+ß), HB-EGF, and HGF resulting in improved accuracy and a validated negative predictive value of 96.4%. CONCLUSIONS: Angiogenesis biomarkers may be useful in discriminating stage I NSCLC from benign pulmonary nodules.

Value of circulating insulin-like growth factor-associated proteins for the detection of stage I non-small cell lung cancer.

OBJECTIVE: Circulating biomarkers related to insulin-like growth factor (IGF) signaling are associated with disease progression in multiple carcinomas, but their potential diagnostic value for lung cancer screening has been inadequately examined. We evaluated 9 circulating IGF-related factors for their ability to assign clinical significance to indeterminate pulmonary nodules identified via computed tomography-based radiologic studies. METHODS: Patients (n = 224 stage I non-small cell lung cancer; n = 123 benign) were enrolled by Rush University and the Mayo Clinic and had pretreatment serum evaluated for levels of IGF-1, IGF-2, and insulin-like growth factor binding proteins (IGFBPs) 1-7. The Mann-Whitney rank-sum test and receiver-operator characteristics curves were used to assess differences in biomarker concentrations relevant to malignant versus benign pathology. These targets were used to help refine our companion blood test for assigning clinical significance to computed tomography-detected solitary nodules (discovery cohort, n = 94) and were validated against an independent cohort from the Mayo Clinic (n = 81). RESULTS: Patients with benign pulmonary nodules were found to have serum concentrations of IGFBP-3, IGFBP-5, IGF-1, and IGF-2 that were higher (P = .001, P < .001, P = .002, and P = .011, respectively) than those with non-small cell lung cancer, with distinct associations with histologic subtypes observed. Refinement of our multianalyte classification algorithm using IGF-related factors provided a new panel consisting of interleukin-6, interleukin-1 receptor antagonist, interleukin-10, stromal cell-derived factor-1(α + ß), IGFBP-4, IGFBP-5, and IGF-2 with improved assay performance-achieving a (validated) negative predictive value of 100%. CONCLUSIONS: Our findings suggest a divergent role for IGF signaling in the biology of benign and malignant pulmonary nodules. Upon further validation, these observations may help identify cases of false positives resulting from computed tomography-based screening studies.

Circulating angiogenesis biomarkers are associated with disease progression in lung adenocarcinoma.

BACKGROUND: Dysregulation of angiogenesis is known to be associated with tumorigenesis and metastatic progression in multiple carcinomas. The aim of this study was to evaluate the prognostic value of circulating angiogenesis biomarkers in lung adenocarcinoma progression. For that, we hypothesize that circulating levels of biomarkers characteristic for discrete processes within angiogenesis are associated with specific phases of disease progression. Appreciation of these profiles may have important implications for disease detection and prognostication. METHODS: Patients with lung adenocarcinoma enrolled in the study were grouped as follows: node negative (T1a-3N0M0; n = 69), node positive (T1a-4N1-2M0; n = 60), and disseminated disease (TxNxM1; n = 68). All serum specimens were assayed for 17 angiogenesis biomarkers on the Luminex platform and statistically evaluated by analysis of variance for median differences in biomarker concentration at distinct phases of disease progression and by log rank methods for associations with clinical outcome. RESULTS: We found circulating hepatocyte growth factor, heparin-binding epidermal growth factor, epidermal growth factor, and vascular endothelial growth factor-C levels significantly elevated (p < 0.05) in patients with node positive versus node negative disease. Similarly, median serum concentrations of bone morphogenic protein-9, endoglin, fibroblast growth factor-1, fibroblast growth factor-2, interleukin-8, placental growth factor, vascular endothelial growth factor-C, and vascular endothelial growth factor-D were significantly (p < 0.05) higher in patients with disseminated disease than in patients with node positive disease. Five biomarkers total were strongly prognostic (p < 0.05) for overall survival in the node negative cohort. CONCLUSIONS: Angiogenesis is a process central to lung adenocarcinoma progression. We describe the modulation in serum angiogenesis biomarker concentrations through the various phases of non-small cell lung cancer progression. Additional refinement efforts are under way to enhance test performance, followed by additional validation studies.

Chronic alcohol exposure renders epithelial cells vulnerable to bacterial infection.

Despite two centuries of reports linking alcohol consumption with enhanced susceptibility to bacterial infections and in particular gut-derived bacteria, there have been no studies or model systems to assess the impact of long-term alcohol exposure on the ability of the epithelial barrier to withstand bacterial infection. It is well established that acute alcohol exposure leads to reduction in tight and adherens junctions, which in turn leads to increases in epithelial cellular permeability to bacterial products, leading to endotoxemia and a variety of deleterious effects in both rodents and human. We hypothesized that reduced fortification at junctional structures should also reduce the epithelial barrier's capacity to maintain its integrity in the face of bacterial challenge thus rendering epithelial cells more vulnerable to infection. In this study, we established a cell-culture based model system for long-term alcohol exposure to assess the impact of chronic alcohol exposure on the ability of Caco-2 intestinal epithelial cells to withstand infection when facing pathogenic bacteria under the intact or wounded conditions. We report that daily treatment with 0.2% ethanol for two months rendered Caco-2 cells far more susceptible to wound damage and cytotoxicity caused by most but not all bacterial pathogens tested in our studies. Consistent with acute alcohol exposure, long-term ethanol exposure also adversely impacted tight junction structures, but in contrast, it did not affect the adherens junction. Finally, alcohol-treated cells partially regained their ability to withstand infection when ethanol treatment was ceased for two weeks, indicating that alcohol's deleterious effects on cells may be reversible.