The role of inflammation in the pathogenesis of lung cancer

Inhibition of the Hedgehog Signaling Pathway Depresses the Cigarette Smoke-Induced Malignant Transformation of 16HBE Cells on a Microfluidic Chip

Background

The hedgehog signaling system (HHS) plays an important role in the regulation of cell proliferation and differentiation during the embryonic phases. However, little is known about the involvement of HHS in the malignant transformation of cells. This study aimed to detect the role of HHS in the malignant transformation of human bronchial epithelial (16HBE) cells.

Methods

In this study, two microfluidic chips were designed to investigate cigarette smoke extract (CSE)-induced malignant transformation of cells. Chip A contained a concentration gradient generator, while chip B had four cell chambers with a central channel. The 16HBE cells cultured in chip A were used to determine the optimal concentration of CSE for inducing malignant transformation. The 16HBE cells in chip B were cultured with 12.25% CSE (Group A), 12.25% CSE + 5 μmol/L cyclopamine (Group B), or normal complete medium as control for 8 months (Group C), to establish the in vitro lung inflammatory-cancer transformation model. The transformed cells were inoculated into 20 nude mice as cells alone (Group 1) or cells with cyclopamine (Group 2) for tumorigenesis testing. Expression of HHS proteins was detected by Western blot. Data were expressed as mean ± standard deviation. The t-test was used for paired samples, and the difference among groups was analyzed using a one-way analysis of variance.

Results

The optimal concentration of CSE was 12.25%. Expression of HHS proteins increased during the process of malignant transformation (Group B vs. Group A, F = 7.65, P < 0.05). After CSE exposure for 8 months, there were significant changes in cellular morphology, which allowed the transformed cells to grow into tumors in 40 days after being inoculated into nude mice. Cyclopamine could effectively depress the expression of HHS proteins (Group C vs. Group B, F = 6.47, P < 0.05) and prevent tumor growth in nude mice (Group 2 vs. Group 1, t = 31.59, P < 0.01).

Conclusions

The activity of HHS is upregulated during the CSE-induced malignant transformation of 16HBE cells. Cyclopamine can effectively depress expression of HHS proteins in vitro and prevent tumor growth of the transformed cells in vivo.

Lung cancer: a new frontier for microbiome research and clinical translation

The lung microbiome has been shown to reflect a range of pulmonary diseases—for example: asthma, chronic obstructive pulmonary disease (COPD) and cystic fibrosis. Studies have now begun to show microbiological changes in the lung that correlate with lung cancer (LC) which could provide new insights into lung carcinogenesis and new biomarkers for disease screening. Clinical studies have suggested that infections with tuberculosis or pneumonia increased the risk of LC possibly through inflammatory or immunological changes. These have now been superseded by genomic-based microbiome sequencing studies based on bronchoalveolar lavage, sputum or saliva samples. Although some discrepancies exist, many have suggested changes in particular bacterial genera in LC samples particularly, Granulicatella, Streptococcus and Veillonella. Granulicatella is of particular interest, as it appeared to show LC stage-specific increases in abundance. We propose that these microbial community changes are likely to reflect biochemical changes in the LC lung, linked to an increase in anaerobic environmental niches and altered pyridoxal/polyamine/nitrogenous metabolism to which Granulicatella could be particularly responsive. These are clearly preliminary observations and many more expansive studies are required to develop our understanding of the LC microbiome.

The impact of exogenous CO releasing molecule CORM-2 on inflammation and signaling of orthotopic lung cancer

The present study aimed to evaluate the therapeutic effect of CO-releasing molecule-2 (CORM-2) in an established mouse orthotopic lung cancer model and investigate the underlying mechanism associated with inflammation pathway. A total of 80 mice were randomly divided into two groups with 20 serving as a normal control and 60 used for the orthotopic lung cancer model. The tumor group was either untreated, or administrated with DMSO or CORM-2. The mice were sacrificed at day 7 and 14 post-treatment, and the body weight, and thymus and spleen indices were determined. Pathological analysis was performed with hematoxylin and eosin (HE) staining. Serous inflammatory factors were measured using an ELISA. The expression levels of eukaryotic translation initiation factor 4E, p70S6K and toll-like receptor-4 (TLR4) were quantified by reverse transcription-polymerase chain reaction. The effects of CORM-2 on the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR), TLR4/nuclear factor (NF)-κB signaling pathways were determined by western blotting. The body weight increased over time in the control group, while it significantly declined in tumor-bearing mice (P<0.05). CORM-2 treatment significantly increased body weight in comparison with the model and DSMO treatment groups (P<0.05). The thymus and spleen indices both reduced in the model and DMSO treatment groups, which was significantly rescued with CORM-2 administration (P<0.05). The HE staining results demonstrated few nodule formations, fibrous hyperplasia and extensive necrosis, which suggested overt inhibitory effects against cancer of CORM-2. The serous contents of tumor necrosis factor-α, interleukin (IL)-1β and IL-6 in the CORM-2 group was significantly lower compared with that in the model and DMSO groups (P<0.05). The ratio of phosphorylated (p-PI3K/PI3K, p-AKT/AKT, p-mTOR/mTOR, p-NF-κB-p65/NF-κB-p65 and expression of TLR4 significantly decreased in the CORM-2 group compared with the model and DMSO groups (P<0.05). To the best of our knowledge, the data in the present study demonstrated in vivo for the first time, the therapeutic potential of the CORM complex, which is associated with suppression of inflammation and general protein synthesis.

Genome-wide MicroRNA Expression Profiles in COPD: Early Predictors for Cancer Development

Chronic obstructive pulmonary disease (COPD) significantly increases the risk of developing cancer. Biomarker studies frequently follow a case-control set-up in which patients diagnosed with a disease are compared to controls. Longitudinal cohort studies such as the COPD-centered German COPD and SYstemic consequences-COmorbidities NETwork (COSYCONET) study provide the patient and biomaterial base for discovering predictive molecular markers. We asked whether microRNA (miRNA) profiles in blood collected from COPD patients prior to a tumor diagnosis could support an early diagnosis of tumor development independent of the tumor type. From 2741 participants of COSYCONET diagnosed with COPD, we selected 534 individuals including 33 patients who developed cancer during the follow-up period of 54 months and 501 patients who did not develop cancer, but had similar age, gender and smoking history. Genome-wide miRNA profiles were generated and evaluated using machine learning techniques. For patients developing cancer we identified nine miRNAs with significantly decreased abundance (two-tailed unpaired t-test adjusted for multiple testing P < 0.05), including members of the miR-320 family. The identified miRNAs regulate different cancer-related pathways including the MAPK pathway (P = 2.3 × 10⁻⁵). We also observed the impact of confounding factors on the generated miRNA profiles, underlining the value of our matched analysis. For selected miRNAs, qRT-PCR analysis was applied to validate the results. In conclusion, we identified several miRNAs in blood of COPD patients, which could serve as candidates for biomarkers to help identify COPD patients at risk of developing cancer.

MiR-5702 suppresses proliferation and invasion in non-small-cell lung cancer cells via posttranscriptional suppression of ZEB1

MiRNAs have emerged as important players in tumorigenesis and progression. MiR-5702 is a newly identified miRNA; the exact role of which has not been reported. Here, we found that miR-5702 was significantly decreased in the carcinoma tissues of non-small cell lung cancer (NSCLC) patients and NSCLC cell lines. Then, our results showed that the miR-5702 mimic induced apoptosis and inhibited proliferation and invasion in A549 cells. In contrast, the miR-5702 inhibitor reduced apoptosis and increased proliferation and invasion in A549 cells. Furthermore, bioinformatics and 3'-UTR luciferase reporter assays identified that oncogene zinc finger E-box-binding homeobox 1 (ZEB1) is a target gene of miR-5702. Western blotting analysis showed that miR-5702 overexpression suppressed, and miR-5702 knockdown promoted the expression of ZEB1 protein. Finally, the ZEB1 siRNA exhibited a similar effect to the miR-5702 mimic on expression of ZEB1 and its downstream genes, cell apoptosis, cell proliferation, and cell invasion, and it could antagonize the alternations in ZEB1 expression and cell behaviors by the miR-5702 inhibitor. In conclusion, miR-5702 may function as a tumor suppressor in NSCLC, which suppresses proliferation and invasion NSCLC cells via posttranscriptional suppression of ZEB1.

Function of PM2.5 in the pathogenesis of lung cancer and chronic airway inflammatory diseases

Previous research has identified that air pollution is associated with various respiratory diseases, but few studies have investigated the function served by particulate matter 2.5 (PM2.5) in these diseases. PM2.5 is known to cause epigenetic and microenvironmental alterations in lung cancer, including tumor-associated signaling pathway activation mediated by microRNA dysregulation, DNA methylation, and increased levels of cytokines and inflammatory cells. Autophagy and apoptosis of tumor cells may also be detected in lung cancer associated with PM2.5 exposure. A number of mechanisms are involved in triggering and aggravating asthma and COPD, including PM2.5-induced cytokine release and oxidative stress. The present review is an overview of the underlying molecular mechanisms of PM2.5-induced pathogenesis in lung cancer and chronic airway inflammatory diseases.

Deficiency of IL-18 Aggravates Esophageal Carcinoma Through Inhibiting IFN-γ Production by CD8+T Cells and NK Cells

To investigate the potential role of interleukin-18 (IL-18) in immunomodulation during tumorigenesis of esophageal carcinoma and elucidate the underlying molecular mechanism, we employed IL-18 knockout mice for this purpose. Carcinogen 4-nitroquinoline 1-oxide (4NQO) was administrated in drinking water to induce occurrence of esophageal squamous cell carcinoma (ESCC). T cell activation as indicated by the surface CD molecules was analyzed with flow cytometry. The serous content of interferon-γ (IFN-γ) along with other cytokines was determined by inflammatory human cytokine cytometric bead array. The cytotoxicity assay was performed by co-culture of tumor cells with immune cells and relative cell viability was determined by lactate dehydrogenase (LDH) assay. Apoptotic cells were stained with Annexin-V/propidium iodide (PI) and analyzed by flow cytometry. Cell proliferation was measured with Cell Counting Kit-8 (CCK-8) assay. Our data demonstrated that deficiency of IL-18 promoted the progression and development of 4NQO-induced ESCC. Loss of IL-18 suppressed the activation of T cells in the esophagus. Deficiency of IL-18 inhibited the IFN-γ production by CD8+ T cells and natural killer (NK) cells. Absence of IL-18 inhibited the cytotoxicity of CD8+ T cells and NK cell in vitro. Moreover, deficiency of IL-18 promoted the apoptosis of CD8+ T cells and inhibited the proliferation of CD8+ T cells in vitro. Our data elucidated the immunomodulatory role of IL-18 during tumorigenesis of ESCC, whose deficiency compromised antitumor immunity and contributed to immune escape of esophageal carcinoma. Our results also indicated the therapeutic potential of exogenous IL-18 against ESCC, which warrants further investigations.

Statins dose-dependently exert a significant chemopreventive effect on colon cancer in patients with chronic obstructive pulmonary disease: A population-based cohort study

Purpose

We evaluated the chemopreventive effect of statins on colon cancer in patients with chronic obstructive pulmonary disease (COPD) and identified the statin exerting the strongest chemopreventive effect.

Methods

Using the National Health Insurance Research Database, we identified patients who received a COPD diagnosis in Taiwan between January 1, 2001, and December 31, 2012, and included them in the study cohort. Each patient was followed to assess the colon cancer risk and protective factors. A propensity score was derived using a logistic regression model to estimate the effect of statins by accounting for covariates predicted during the intervention (statins). To examine the dose–response relationship, we categorized statin doses into four groups in each cohort [<28, 28–90, 91–365, and >365 cumulative defined daily dose].

Results

Compared with the statin nonusers, the adjusted hazard ratio (aHR) for colon cancer decreased in the statin users (aHR = 0.52, 95% confidence interval = 0.44, 0.62). Hydrophilic statins exerted a stronger preventive effect against colon cancer. Regarding the statin type, lovastatin, pravastatin, and fluvastatin nonsignificantly reduced the colon cancer risk in the patients with COPD. Compared with the statin nonusers, the aHRs for colon cancer decreased in the individual statin users (rosuvastatin, simvastatin, and atorvastatin: aHRs = 0.28, 0.64, and 0.65, respectively). In the sensitivity analysis, statins dose-dependently reduced the colon cancer risk.

Conclusions

Statins dose-dependently exert significant chemopreventive effects on colon cancer in patients with COPD, with rosuvastatin exerting the largest chemopreventive effect.

Statins dose-dependently exert a chemopreventive effect against lung cancer in COPD patients: a population-based cohort study

Purpose

Chronic obstructive pulmonary disease (COPD) is associated with increased lung cancer risk. We evaluated the association of statin use with lung cancer risk in COPD patients and identified which statins possess the highest chemopreventive potential.

Results

After adjustment for age, sex, CCI, diabetes, hypertension, dyslipidemia, urbanization level, and monthly income according to propensity scores, lung cancer risk in the statin users was lower than that in the statin nonusers (adjusted hazard ratio [aHR] = 0.37). Of the individual statins, lovastatin and fluvastatin did not reduce lung cancer risk significantly. By contrast, lung cancer risk in patients using rosuvastatin, simvastatin, atorvastatin, and pravastatin was significantly lower than that in statin nonusers (aHRs = 0.41, 0.44, 0.52, and 0.58, respectively). Statins dose-dependently reduced lung cancer risk in all subgroups and the main model with additional covariates (nonstatin drug use).

MATERIALS AND METHODS

The study cohort comprised all patients diagnosed with COPD at health care facilities in Taiwan (n = 116,017) between January 1, 2001 and December 31, 2012. Our final study cohort comprised 43,802 COPD patients: 10,086 used statins, whereas 33,716 did not. Patients were followed up to assess lung cancer risk or protective factors. In addition, we also considered demographic characteristics, namely age, sex, comorbidities (diabetes, hypertension, dyslipidemia, and Charlson comorbidity index [CCI]), urbanization level, monthly income, and nonstatin drug use. The index date of statin use was the COPD confirmation date. To examine the dose–response relationship, we categorized statin use into four groups in each cohort: < 28, 28–90, 91–365, and > 365 cumulative defined daily doses (cDDDs). Patients receiving < 28 cDDDs were defined as nonstatin users.

Conclusions

Statins dose-dependently exert a significant chemopreventive effect against lung cancer in COPD patients. Rosuvastatin, simvastatin, and atorvastatin exhibited the highest chemopreventive potential.

Profile of epigenetic mechanisms in lung tumors of patients with underlying chronic respiratory conditions

Background

Chronic lung diseases such as chronic obstructive pulmonary disease (COPD) and epigenetic events underlie lung cancer (LC) development. The study objective was that lung tumor expression levels of specific microRNAs and their downstream biomarkers may be differentially regulated in patients with and without COPD.

Methods

In lung specimens (tumor and non-tumor), microRNAs known to be involved in lung tumorigenesis (miR-21, miR-200b, miR-126, miR-451, miR-210, miR-let7c, miR-30a-30p, miR-155 and miR-let7a, qRT-PCR), DNA methylation, and downstream biomarkers were determined (qRT-PCR and immunoblotting) in 40 patients with LC (prospective study, subdivided into LC-COPD and LC, N = 20/group).

Results

Expression of miR-21, miR-200b, miR-210, and miR-let7c and DNA methylation were greater in lung tumor specimens of LC-COPD than of LC patients. Expression of downstream markers PTEN, MARCKs, TPM-1, PDCD4, SPRY-2, ETS-1, ZEB-2, FGFRL-1, EFNA-3, and k-RAS together with P53 were selectively downregulated in tumor samples of LC-COPD patients. In these patients, tumor expression of miR-126 and miR-451 and that of the biomarkers PTEN, MARCKs, FGFRL-1, SNAIL-1, P63, and k-RAS were reduced.

Conclusions

Biomarkers of mechanisms involved in tumor growth, angiogenesis, migration, and apoptosis were differentially expressed in tumors of patients with underlying respiratory disease. These findings shed light into the underlying biology of the reported greater risk to develop LC seen in patients with chronic respiratory conditions. The presence of an underlying respiratory disease should be identified in all patients with LC as the differential biological profile may help determine tumor progression and the therapeutic response. Additionally, epigenetic events offer a niche for pharmacological therapeutic targets.

Occupational exposure to diesel engine exhaust and alterations in immune/inflammatory markers: a cross-sectional molecular epidemiology study in China

The relationship between diesel engine exhaust (DEE), a known lung carcinogen, and immune/inflammatory markers that have been prospectively associated with lung cancer risk is not well understood. To provide insight into these associations, we conducted a cross-sectional molecular epidemiology study of 54 males highly occupationally exposed to DEE and 55 unexposed male controls from representative workplaces in China. We measured plasma levels of 64 immune/inflammatory markers in all subjects using Luminex bead-based assays, and compared our findings to those from a nested case-control study of these markers and lung cancer risk, which had been conducted among never-smoking women in Shanghai using the same multiplex panels. Levels of nine markers that were associated with lung cancer risk in the Shanghai study were altered in DEE-exposed workers in the same direction as the lung cancer associations. Among these, associations with the levels of CRP (β= -0.53; P = 0.01) and CCL15/MIP-1D (β = 0.20; P = 0.02) were observed in workers exposed to DEE and with increasing elemental carbon exposure levels (Ptrends <0.05) in multivariable linear regression models. Levels of a third marker positively associated with an increased lung cancer risk, CCL2/MCP-1, were higher among DEE-exposed workers compared with controls in never and former smokers, but not in current smokers (Pinteraction = 0.01). The immunological differences in these markers in DEE-exposed workers are consistent with associations observed for lung cancer risk in a prospective study of Chinese women and may provide some insight into the mechanistic processes by which DEE causes lung cancer.

Cancer and Aging - the Inflammatory Connection

Aging and cancer are highly correlated biological phenomena. Various cellular processes such as DNA damage responses and cellular senescence that serve as tumor suppressing mechanisms throughout life result in degenerative changes and contribute to the aging phenotype. In turn, aging is considered a pro-tumorigenic state, and constitutes the single most important risk factor for cancer development. However, the causative relations between aging and cancer is not straight forward, as these processes carry contradictory hallmarks; While aging is characterized by tissue degeneration and organ loss of function, cancer is a state of sustained cellular proliferation and gain of new functions. Here, we review the molecular and cellular pathways that stand in the base of aging related cancer. Specifically, we deal with the inflammatory perspective that link these two processes, and suggest possible molecular targets that may be exploited to modify their courses.

The Biology of Aging and Cancer: A Brief Overview of Shared and Divergent Molecular Hallmarks

Aging is the inevitable time-dependent decline in physiological organ function and is a major risk factor for cancer development. Due to advances in health care, hygiene control and food availability, life expectancy is increasing and the population in most developed countries is shifting to an increasing proportion of people at a cancer susceptible age. Mechanisms of aging are also found to occur in carcinogenesis, albeit with shared or divergent end-results. It is now clear that aging and cancer development either share or diverge in several disease mechanisms. Such mechanisms include the role of genomic instability, telomere attrition, epigenetic changes, loss of proteostasis, decreased nutrient sensing and altered metabolism, but also cellular senescence and stem cell function. Cancer cells and aged cells are also fundamentally opposite, as cancer cells can be thought of as hyperactive cells with advantageous mutations, rapid cell division and increased energy consumption, while aged cells are hypoactive with accumulated disadvantageous mutations, cell division inability and a decreased ability for energy production and consumption. Nonetheless, aging and cancer are tightly interconnected and many of the same strategies and drugs may be used to target both, while in other cases antagonistic pleiotrophy come into effect and inhibition of one can be the activation of the other. Cancer can be considered an aging disease, though the shared mechanisms underpinning the two processes remain unclear. Better understanding of the shared and divergent pathways of aging and cancer is needed.

Muc1 knockout potentiates murine lung carcinogenesis involving an epiregulin-mediated EGFR activation feedback loop

Mucin 1 (MUC1) is a tumor antigen that is aberrantly overexpressed in various cancers, including lung cancer. Our previous in vitro studies showed that MUC1 facilitates carcinogen-induced EGFR activation and transformation in human lung bronchial epithelial cells (HBECs), which along with other reports suggests an oncogenic property for MUC1 in lung cancer. However, direct evidence for the role of MUC1 in lung carcinogenesis is lacking. In this study, we used the 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced A/J mouse lung tumor model to investigate the effect of whole-body Muc1 knockout (KO) on carcinogen-induced lung carcinogenesis. Surprisingly, lung tumor multiplicity was significantly increased in Muc1 KO compared to wild-type (WT) mice. The EGFR/AKT pathway was unexpectedly activated, and expression of the EGFR ligand epiregulin (EREG) was increased in the lung tissues of the Muc1 KO compared to the WT mice. EREG stimulated proliferation and protected against cigarette smoke extract (CSE)-induced cytotoxicity in in vitro cultured human bronchial epithelial cells. Additionally, we determined that MUC1 was expressed in human fibroblast cell lines where it suppressed CSE-induced EREG production. Further, suppression of MUC1 cellular activity with GO-201 enhanced EREG production in lung cancer cells, which in turn protected cancer cells from GO-201-induced cell death. Moreover, an inverse association between MUC1 and EREG was detected in human lung cancer, and EREG expression was inversely associated with patient survival. Together, these results support a promiscuous role of MUC1 in lung cancer development that may be related to cell-type specific functions of MUC1 in the tumor microenvironment, and MUC1 deficiency in fibroblasts and malignant cells results in increased EREG production that activates the EGFR pathway for lung carcinogenesis.

Elevated preoperative neutrophil-to-lymphocyte ratio can predict poor survival in early stage gastric cancer patients receiving radical gastrectomy: The Fujian prospective investigation of cancer (FIESTA) study

Aims: This cohort study was conducted to evaluate the prognostic impact of blood-routine parameters before radical gastrectomy on gastric cancer mortality.

Methods: Total 3012 patients with gastric cancer were consecutively enrolled from a mono-center between 2000 and 2010, and the latest follow-up was completed in 2015.

Results: The median follow-up time was 44.05 months. Finally, 1331 out of 3012 gastric cancer patients died from gastric cancer. Per standard deviation increment in neutrophil (hazard ratio or HR=1.08, P<0.001), white blood cell count (HR=1.07, P=0.001), neutrophil-to-lymphocyte ratio or NLR (HR=1.08, P<0.001) and platelet-to-lymphocyte ratio (HR=1.08, P<0.001) was significantly associated with an increased risk of gastric cancer mortality, while that in lymphocyte (HR=0.69, P<0.001), hemoglobin (HR=0.82, P<0.001) and lymphocyte-to-monocyte ratio (HR=0.68, P<0.001) was associated with a reduced risk. Survival tree analysis indicated that in patients with TNM stage I/II, the contrasts of NLR>2.61 with ≤2.61 and NLR>1.87 with ≤1.87 were respectively associated with a 5.21-fold (P=0.004) and 2.36-fold (P=0.001) increased risk of gastric cancer mortality. The effect-size magnitude of NLR was further potentiated in patients with invasion depth T1/T2 (HR=1.73, P=0.001), regional lymph node metastasis N0 (HR=1.60, P<0.001), TNM stage I/II (HR=1.36, P=0.009) and tumor size ≤ 4.5 cm (HR=1.17, P<0.001).

Conclusions: Our findings consolidated the prognostic impact of preoperative NLR on gastric mortality, and demonstrated that elevated preoperative NLR was a robust indicator of poor survival in patients at early stage.

In vitro Monocyte IL-6 Secretion Levels Following Stimulation with Autologous Spheroids Derived from Tumour or Benign Mucosa Predict Long-term Survival in Head and Neck Squamous Cell Carcinoma Patients

MCP-1/IL-6 in vitro monocyte secretion upon coculture with autologous fragment spheroids was studied in relation to patient 5- and 10-year overall survival rates in head and neck squamous cell carcinoma (HNSCC) patients (n = 65) diagnosed between 1998 and 2005, nine of whom had an human papilloma virus (HPV) tumour infection. The spheroids were harvested from malignant or benign tissue during primary surgery. Two weeks following surgery, freshly isolated autologous monocytes and benign or malignant spheroids were cocultured 24 h in vitro. The IL-6 secretion was expressed as a fraction of the lipopolysaccharide (LPS) response from the same batch of monocytes. HPV status was obtained by employing PCR analyses of primary diagnostic blocks. IL-6/MCP-1 response levels were not found to be dependent on HPV infection status. MCP-1 secretion did not predict prognosis, nor did in vitro IL-6 monocyte background or LPS-stimulated IL-6 secretion. At 5-year observation, dichotomized IL-6 levels following monocyte coculture, with both malignant and benign spheroids, showed a strong trend towards predicting survival, that is a low monocyte malignant coculture response showed a survival of 31 ± 17 versus 58 ± 17% with a high such response (P = 0.057). When studying monocyte IL-6 coculture responses evaluating benign and malignant spheroid results statistically together, a prediction of survival up to 10 years was found (hazard ratio = 0.48; confidence interval = 0.24-0.96; P < 0.05) with double low IL-6 responses. This survival prediction was also present after an adjustment for HPV tumour infection status. In conclusion, monocyte IL-6 in vitro secretion in cocultures with autologous spheroids/serum from HNSCCs predicted 5- and 10-year survivals, both with and without tumour HPV tumour adjustment.

Plausible Roles for RAGE in Conditions Exacerbated by Direct and Indirect (Secondhand) Smoke Exposure

Approximately 1 billion people smoke worldwide, and the burden placed on society by primary and secondhand smokers is expected to increase. Smoking is the leading risk factor for myriad health complications stemming from diverse pathogenic programs. First- and second-hand cigarette smoke contains thousands of constituents, including several carcinogens and cytotoxic chemicals that orchestrate chronic inflammatory responses and destructive remodeling events. In the current review, we outline details related to compromised pulmonary and systemic conditions related to smoke exposure. Specifically, data are discussed relative to impaired lung physiology, cancer mechanisms, maternal-fetal complications, cardiometabolic, and joint disorders in the context of smoke exposure exacerbations. As a general unifying mechanism, the receptor for advanced glycation end-products (RAGE) and its signaling axis is increasingly considered central to smoke-related pathogenesis. RAGE is a multi-ligand cell surface receptor whose expression increases following cigarette smoke exposure. RAGE signaling participates in the underpinning of inflammatory mechanisms mediated by requisite cytokines, chemokines, and remodeling enzymes. Understanding the biological contributions of RAGE during cigarette smoke-induced inflammation may provide critically important insight into the pathology of lung disease and systemic complications that combine during the demise of those exposed.

Systemic and Tumor Th1 and Th2 Inflammatory Profile and Macrophages in Lung Cancer: Influence of Underlying Chronic Respiratory Disease

INTRODUCTION

Chronic respiratory conditions, especially chronic obstructive pulmonary disease (COPD), and inflammatory events underlie lung cancer (LC). We hypothesized that profiles of T helper 1 and T helper 2 cytokines and type 1 and type 2 macrophages (M1 and M2) are differentially expressed in lung tumors and blood of patients with NSCLC with and without COPD and that the ratio M1/M2 specifically may influence their survival.

METHODS

In blood, inflammatory cytokines (determined by enzyme-linked immunosorbent assay) were quantified in 80 patients with LC (60 with LC and COPD [the LC-COPD group] and 20 with LC only [the LC-only group]) and lung specimens (tumor and nontumor) from those undergoing thoracotomy (20 in the LC-COPD group and 20 in the LC-only group).

RESULTS

In the LC-COPD group compared with in the LC-only group, systemic levels of tumor necrosis factor-α, interleukin-2 (IL-2), transforming growth factor-β, and IL-10 were increased, whereas vascular endothelial growth factor and IL-4 levels were decreased. In lung tumors, levels of tumor necrosis factor-α, transforming growth factor-β, and IL-10 were higher than in nontumor parenchyma in the LC-COPD group, whereas IL-2 and vascular endothelial growth factor levels were higher in tumors of both the LC-only and LC-COPD groups. Compared with in nontumor lung, M1 macrophage counts were reduced whereas M2 counts were increased in tumors of both patient groups, and the M1/M2 ratio was higher in the LC-COPD group than the LC-only group. M1 and M2 counts did not influence patients' survival.

CONCLUSIONS

The relative predominance of T helper 1 cytokines and M1 macrophages in the blood and tumors of patients with underlying COPD imply that a stronger proinflammatory pattern exists in these patients. Inflammation should not be targeted systematically in all patients with LC. Screening for the presence of underlying respiratory diseases and identification of the specific inflammatory pattern should be carried out in patients with LC, at least in early stages of their disease.

Relationships between chronic obstructive pulmonary disease and lung cancer: biological insights

Lung cancer (LC) has become one of the leading causes of preventable death in the last few decades. Cigarette smoking (CS) stays as the main etiologic factor of LC despite that many other causes such as occupational exposures, air pollution, asbestos, or radiation have also been implicated. Patients with chronic obstructive pulmonary disease (COPD), which also represents a major cause of morbidity and mortality in developed countries, exhibit a significantly greater risk of LC. The study of the underlying biological mechanisms that may predispose patients with chronic respiratory diseases to a higher incidence of LC has also gained much attention in the last few years. The present review has been divided into three major sections in which different aspects have been addressed: (I) relevant etiologic agents of LC; (II) studies confirming the hypothesis that COPD patients are exposed to a greater risk of developing LC; and (III) evidence on the most relevant underlying biological mechanisms that support the links between COPD and LC. Several carcinogenic agents have been described in the last decades but CS remains to be the leading etiologic agent in most geographical regions in which the incidence of LC is very high. Growing evidence has put the line forward the implications of COPD and especially of emphysema in LC development. Hence, COPD represents a major risk factor of LC in patients. Different avenues of research have demonstrated the presence of relevant biological mechanisms that may predispose COPD patients to develop LC. Importantly, the so far identified biological mechanisms offer targets for the design of specific therapeutic strategies that will further the current treatment options for patients with LC. Prospective screening studies, in which patients with COPD should be followed up for several years will help identify biomarkers that may predict the risk of LC among these patients.

Inflammation has a role in urethane‑induced lung cancer in C57BL/6J mice

Lung cancer is a common and highly frequent cause of cancer‑associated mortality worldwide. Several studies have indicated that chronic inflammation is associated with an increased risk of several types of human cancer. The lung is vulnerable to various chemical and biological insults, and persistent exposure to these factors may result in the release of several inflammatory cytokines from inflammatory cells, thus leading to chronic inflammation and a risk of lung cancer. Due to the extensive application of C57BL/6J mice in lipid metabolism‑related research, it appears important to establish a lung cancer model based on C57BL/6J mice. Therefore, the present study designed an experimental model, in which C57BL/6J mice received several injections of urethane. The study aimed to explore whether inflammation has a role in this model of lung cancer. The results demonstrated that 10 weekly intraperitoneal injections of urethane induced a 100% lung tumor incidence, and urethane‑treated mice possessed higher numbers of immune cells. In addition, the expression levels of cytokines and chemokines in bronchoalveolar lavage fluid were significantly different between the two groups. Activation of the transcription factor nuclear factor‑κB was increased in the lung tissues of urethane‑treated mice, and its expression was upregulated in a time‑dependent manner. These results suggested that the accumulation of lung inflammation may be associated with the occurrence of lung cancer in C57BL/6J mice.

SIRT1 in B[a]P-induced lung tumorigenesis

Benzo[a]pyrene (B[a]P) is a carcinogen in cigarette smoke. We found that B[a]P induced SIRT1 in human bronchial epithelial BEAS-2B cell. SIRT1 was overexpressed in the lung of B[a]P-exposed mice and in human lung cancer biopsies. SIRT1 up-regulated TNF-α and β-catenin and down-regulated the membrane fraction of E-cadherin. In addition, SIRT1 promoted invasion, migration and tumorigenesis of BEAS-2B cells in nude mice upon B[a]P exposure. Thus, SIRT1 is involved in B[a]P-induced transformation associated with activation of the TNF-α/β-catenin axis and is as a potential therapeutic target for lung cancer.

Executive summary of the SEPAR recommendations for the diagnosis and treatment of non-small cell lung cancer

The Thoracic Surgery and Thoracic Oncology groups of the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR) have backed the publication of a handbook on recommendations for the diagnosis and treatment of non-small cell lung cancer. Due to the high incidence and mortality of this disease, the best scientific evidence must be constantly updated and made available for consultation by healthcare professionals. To draw up these recommendations, we called on a wide-ranging group of experts from the different specialties, who have prepared a comprehensive review, divided into 4 main sections. The first addresses disease prevention and screening, including risk factors, the role of smoking cessation, and screening programs for early diagnosis. The second section analyzes clinical presentation, imaging studies, and surgical risk, including cardiological risk and the evaluation of respiratory function. The third section addresses cytohistological confirmation and staging studies, and scrutinizes the TNM and histological classifications, non-invasive and minimally invasive sampling methods, and surgical techniques for diagnosis and staging. The fourth and final section looks at different therapeutic aspects, such as the role of surgery, chemotherapy, radiation therapy, a multidisciplinary approach according to disease stage, and other specifically targeted treatments, concluding with recommendations on the follow-up of lung cancer patients and surgical and endoscopic palliative interventions in advanced stages.

Lung Malignancies in HIV Infection

Pulmonary malignancies are a major source of morbidity and mortality in HIV-infected persons. Non-AIDS-defining lung cancers (mostly non-small cell lung cancers) are now a leading cause of cancer death among HIV-infected persons. HIV-associated factors appear to affect the risk of lung cancer and may adversely impact cancer treatment and outcomes. HIV infection also may modify the potential harms and benefits of lung cancer screening with computed tomography. AIDS-defining lung malignancies include pulmonary Kaposi sarcoma and pulmonary lymphoma, both of which are less prevalent with widespread adoption of antiretroviral therapy.

Macrophages promote benzopyrene-induced tumor transformation of human bronchial epithelial cells by activation of NF-κB and STAT3 signaling in a bionic airway chip culture and in animal models

We investigated the role of macrophages in promoting benzopyrene (BaP)-induced malignant transformation of human bronchial epithelial cells using a BaP-induced tumor transformation model with a bionic airway chip in vitro and in animal models. The bionic airway chip culture data showed that macrophages promoted BaP-induced malignant transformation of human bronchial epithelial cells, which was mediated by nuclear factor (NF)-κB and STAT3 pathways to induce cell proliferation, colony formation in chip culture, and tumorigenicity in nude mice. Blockage of interleukin (IL)-6 or tumor necrosis factor (TNF)-α signaling or inhibition of NF-κB, STAT3, or cyclinD1 expression abrogated the effect of macrophages on malignant transformation in the bionic airway chip culture. In vivo, macrophages promoted lung tumorigenesis in a carcinogen-induced animal model. Similarly, blockage of NF-κB, STAT3, or cyclinD1 using siRNA transfection decreased the carcinogen-induced tumorigenesis in rats. We demonstrated that macrophages are critical in promoting lung tumorigenesis and that the macrophage-initiated TNF-α/NF-κB/cyclinD1 and IL-6/STAT3/cyclinD1 pathways are primarily responsible for promoting lung tumorigenesis.

Deletion of 5-Lipoxygenase in the Tumor Microenvironment Promotes Lung Cancer Progression and Metastasis through Regulating T Cell Recruitment

Eicosanoids, including PGs, produced by cyclooxygenases (COX), and leukotrienes, produced by 5-lipoxygenase (5-LO) have been implicated in cancer progression. These molecules are produced by both cancer cells and the tumor microenvironment (TME). We previously reported that both COX and 5-LO metabolites increase during progression in an orthotopic immunocompetent model of lung cancer. Although PGs in the TME have been well studied, less is known regarding 5-LO products produced by the TME. We examined the role of 5-LO in the TME using a model in which Lewis lung carcinoma cells are directly implanted into the lungs of syngeneic WT mice or mice globally deficient in 5-LO (5-LO-KO). Unexpectedly, primary tumor volume and liver metastases were increased in 5-LO-KO mice. This was associated with an ablation of leukotriene (LT) production, consistent with production mainly mediated by the microenvironment. Increased tumor progression was partially reproduced in global LTC4 synthase KO or mice transplanted with LTA4 hydrolase-deficient bone marrow. Tumor-bearing lungs of 5-LO-KO had decreased numbers of CD4 and CD8 T cells compared with WT controls, as well as fewer dendritic cells. This was associated with lower levels of CCL20 and CXL9, which have been implicated in dendritic and T cell recruitment. Depletion of CD8 cells increased tumor growth and eliminated the differences between WT and 5-LO mice. These data reveal an antitumorigenic role for 5-LO products in the microenvironment during lung cancer progression through regulation of T cells and suggest that caution should be used in targeting this pathway in lung cancer.

MiR-451 suppresses cell proliferation and metastasis in A549 lung cancer cells

Recent study showed that inflammation was related to lung cancer. However, the exact cause of lung inflammation leading to carcinogenesis is unknown. MicroRNAs (miRNAs) are a group of endogenous non-coding small RNAs that regulate the activity of targeted mRNAs by inflammatory response in many diseases. MiR-451 was reported to relate to the development of lung cancer and metastasis of glioma. But the effect of miR-451 on cell proliferation, migration, and invasion of lung cancer is not really clear. In order to explore the molecular mechanism of the occurrence and development of lung cancer, we investigated the effect of human miR-451 on the proliferation, invasion, and metastasis in lung cancer cell line A549. The miR-451 expression construct was generated into pGenesil-1.1 and transfected into A549 cells. Results showed that the recombinant vectors were verified by sequencing. And miR-451 was over-expressed in A549 by real-time RT PCR. Furthermore, the proliferation, invasion, and metastasis of the cells in miR-451 group were inhibited significantly compared with those in control and A549 groups by MTT assay, Transwell invasion assay, and wound-healing assay. And the lung cancer metastasis factors (MMP-2, MMP-9, VEGF, and CXCR4) were decreased in miR-451 group by Western blot. Moreover, it was proved that inflammation-related gene-PSMB8 was a target for miR-451 by bioinformatics analysis and dual-luciferase reporter assay. And the protein expressions of PSMB8 and NOS2 were decreased in miR-451 group compared with those in control and A549 groups. Therefore, our findings indicated that miR-451 related to PSMB8/NOS2 inflammatory factors may suppress the development and migration of lung cancer, providing evidence for the role of miR-451 in lung cancer.

The prognostic value of serum C-reactive protein-bound serum amyloid A in early-stage lung cancer

Background

Elevated levels of serum C-reactive protein (CRP) have been reported to have prognostic significance in lung cancer patients. This study aimed to further identify CRP-bound components as prognostic markers for lung cancer and validate their prognostic value.

Methods

CRP-bound components obtained from the serum samples from lung cancer patients or healthy controls were analyzed by differential proteomics analysis. CRP-bound serum amyloid A (CRP-SAA) was evaluated by co-immunoprecipitation (IP). Serum samples from two independent cohorts with lung cancer (retrospective cohort, 242 patients; prospective cohort, 222 patients) and healthy controls (159 subjects) were used to evaluate the prognostic value of CRP-SAA by enzyme-linked immunosorbent assay.

Results

CRP-SAA was identified specifically in serum samples from lung cancer patients by proteomic analysis. CRP binding to SAA was confirmed by co-IP in serum samples from lung cancer patients and cell culture media. The level of CRP-SAA was significantly higher in patients than in healthy controls (0.37 ± 0.58 vs. 0.03 ± 0.04, P < 0.001). Elevated CRP-SAA levels were significantly associated with severe clinical features of lung cancer. The elevation of CRP-SAA was associated with lower survival rates for both the retrospective (hazard ration [HR] = 2.181, 95% confidence interval [CI] = 1.641–2.897, P < 0.001) and the prospective cohorts (HR = 2.744, 95% CI = 1.810–4.161, P < 0.001). Multivariate Cox analysis showed that CRP-SAA was an independent prognostic marker for lung cancer. Remarkably, in stages I–II patients, only CRP-SAA, not total SAA or CRP, showed significant association with overall survival in two cohorts. Moreover, univariate and multivariate Cox analyses also showed that only CRP-SAA could be used as an independent prognostic marker for early-stage lung cancer patients.

Conclusion

CRP-SAA could be a better prognostic marker for lung cancer than total SAA or CRP, especially in early-stage patients.

Observational and genetic plasma YKL-40 and cancer in 96,099 individuals from the general population

Plasma YKL-40 is high in patients with cancer and in individuals who later develop cancer. Whether YKL-40 is only a marker or indeed a cause of cancer is presently unknown. We tested the hypothesis that observationally and genetically, high plasma YKL-40 is associated with high risk of cancer. For this purpose, we performed cohort and Mendelian randomization studies in 96,099 individuals from the Danish general population. Plasma levels of YKL-40 were measured in 21,643 and CHI3L1 rs4950928 was genotyped in 94,568 individuals. From 1943 through 2011, 2,291 individuals developed gastrointestinal cancer, 913 developed lung cancer, 2,863 women developed breast cancer, 1,557 men developed prostate cancer and 5,146 individuals developed other cancer. Follow-up was 100% complete. Multifactorially and CRP adjusted hazard ratio (HR) for gastrointestinal cancer was 1.82 (95%CI, 1.16-2.86) for 96-100% versus 0-33% YKL-40 percentile category. Corresponding HR were 1.71 (0.95-3.07) for lung cancer, but insignificant for breast cancer, prostate cancer and other cancers. CHI3L1 rs4950928 genotype was associated with plasmaYKL-40 levels, but not with risk of any cancer category. For gastrointestinal cancer, a doubling in YKL-40 was associated with a multifactorially and CRP adjusted observational HR of 1.14(1.05-1.23) for gastrointestinal cancer, but a corresponding genetic odds ratio of 1.06(0.94-1.18). For lung cancer, corresponding risk estimates were 1.11(1.00-1.22) observationally and 1.01(0.84-1.20) genetically. For other cancer categories, observational and genetic findings were insignificant. This study shows that high plasma YKL-40 levels were associated with high risk of gastrointestinal and likely of lung cancer, but genetic high levels were not.

In Vitro-Stimulated IL-6 Monocyte Secretion and In Vivo Peripheral Blood T Lymphocyte Activation Uniquely Predicted 15-Year Survival in Patients with Head and Neck Squamous Cell Carcinoma

The study was performed in order to determine whether peripheral blood monocyte in vitro function, and lymphocyte in vivo activation at diagnosis, was associated with HPV tumor infection status and 15-year survival in head and neck squamous cell carcinoma (HNSCC) patients. Sixty-five patients from a consecutive cohort of newly diagnosed HNSCCs, together with 18 control patients, were included in the study. Monocyte responsiveness was assessed by measuring monocyte in vitro interleukin (IL)-6 secretions after 24 hours of LPS stimulation in cultures with a serum-free medium. T lymphocyte activation was determined as the fraction of CD71-positive cells on CD3-positive cells by flow cytometry, whereas HPV infection was determined by PCR on formalin-fixed paraffin-embedded (FFPE) tumor tissue. Disease-specific survivals and overall survivals were determined 15 years following inclusion. HPV-positive HNSCC patients had a lower monocyte LPS-stimulated IL-6 response. A high LPS-stimulated monocyte IL-6 response predicted a decreased survival rate (P=0.019). A high percentage of CD71-positive T lymphocytes also predicted an impaired prognosis (P=0.021). The predictive power of IL-6 monocyte LPS-stimulated responses was retained when adjusted for age, gender and TNM stage of the patients. The monocyte and T lymphocyte survival predictions were independent of each other. The survival was particularly low with a combined high activated monocyte and T lymphocyte status. In a multivariate analysis, IL-6 secretion and the percentage of CD71-positive T lymphocytes both uniquely predicted survival independent of HPV infection status. It is postulated that the natural and adaptive immune systems are separately and additionally linked to the clinical aggressiveness of HNSCCs.

Peripheral blood monocyte and T-lymphocyte activation levels at diagnosis predict long-term survival in head and neck squamous cell carcinoma patients

This study was performed to determine whether peripheral blood (PB) monocyte and/or lymphocyte activation at diagnosis were associated with long-term prognosis in patients with head and neck squamous cell carcinoma (HNSCC), and to what extent such prognostic properties relate to human papilloma virus (HPV)-associated tumor infection of the included patients. This was a long-term prospective study describing patient survival in relation to PB T lymphocyte and monocyte activation in patients observed for up to 14 years following diagnosis. Sixty-four patients from a consecutive cohort of newly diagnosed HNSCC patients along with 16 non-cancer control patients were included over a period of almost 2 years. Monocyte responsiveness was assessed at diagnosis (N = 56 HNSCC/16 non-cancer controls) by measuring net levels of spontaneous vs lipopolysaccharide-induced monocyte chemotactic protein (MCP)-1 secretion in vitro. PB T lymphocyte activation was determined (N = 58 HNSCC/16 controls) by measuring the percentage of T cells expressing CD69 by flow cytometry. Whether HPV infection or not was determined by PCR analysis on formalin fixed paraffin-embedded tumor tissue. Tumor HPV-positive patients had better prognosis than HPV-negative patients. A low net MCP-1 response in monocytes predicted increased survival (Relative risk (RR) = 2.1; Confidence interval (CI): 1.1-4.0; p < 0.05). A low percentage of CD69 positive T lymphocytes also predicted better prognosis (RR = 2.6; CI: 1.3-5.0; p = 0.005). The predictive power of MCP-1 monocyte and CD69 T lymphocyte measures were retained when adjusted for age and gender of the patients and shown to be independent of each other (N = 50 HNSCC/16 controls). The results were similar in HPV tumor-positive and -negative patients. Patients with high monocyte- and/or T lymphocyte activation status had low survival with 8% 5 year overall survival (OS) compared to 65% 5 year OS for patients with dual low activation levels (RR = 0.27; CI: 0.14-0.56; p < 0.001), mostly secondary to disease-specific survival. Both tumor HPV-positive and -negative HNSCC patients with high percentage of CD69 positive T lymphocytes and/or high monocyte MCP-1 secretion had low long-term survival. The data suggest that the general inflammatory and adaptive immune systems are independently linked to the clinical aggressiveness of both tumor HPV-negative and -positive HNSCC patients.

MicroRNAs as regulators of airborne pollution-induced lung inflammation and carcinogenesis

The increasing incidence of pulmonary inflammation and lung cancer, as well as exacerbation of pre-existing chronic lung diseases by exposure to airborne pollutants, e.g., particulate matter and cigarette smoke, is becoming a major public health concern in the world. However, the exact mechanisms of pulmonary injury from exposure to these airborne insults have not been fully elucidated. Nevertheless, accumulating evidence suggests that microRNAs (miRNAs) may play a unique role in the regulation of airborne agent-induced lung inflammation and carcinogenesis. Since epigenetic modifications are heritable and reversible, this may provide a new insight into the relationship of miRNAs and environmental pollution-related lung disorders. The aim of this review was to update our existing knowledge regarding the mechanisms by which airborne pollutants altering miRNA profiles in the lung, specifically for cigarette smoke and airborne particulate matter, and the potential biological roles of miRNAs in the initiation of pulmonary inflammation and lung cancer, as well as the regulation of underlying genetic susceptibility to these environmental stressors.

Serum inflammatory factors and circulating immunosuppressive cells are predictive markers for efficacy of radiofrequency ablation in non-small-cell lung cancer

In recent years, percutaneous radiofrequency ablation (RFA) has been developed as a new tool in the treatment of non-small-cell lung cancer (NSCLC) in non-surgical patients. There is growing evidence that RFA-mediated necrosis can modulate host immune responses. Here we analysed serum inflammatory factors as well as immunosuppressive cells in the peripheral blood to discover possible prognostic indicators. Peripheral blood and serum samples were collected before RFA and within 3 months after the treatment in a total of 12 patients. Inflammatory cytokines and growth factors were measured in serum by the Bio-Plex assay. Myeloid-derived suppressor cells (MDSCs) and regulatory T cells (Tregs ) were evaluated in the peripheral blood via flow cytometry. In patients developing local or lymphogenic tumour relapse (n=4), we found an early significant increase in the concentration of tumour necrosis factor (TNF)-α as well as chemokine (C-C motif) ligand (CCL)-2 and CCL-4 compared to patients without relapse (n=4) and healthy donors (n=5). These changes were associated with an elevated activity of circulating MDSC indicated by an increased nitric oxide (NO) production in these cells. Elevated serum levels of TNF-α, CCL-2 and CCL-4 associated with an increased NO production in circulating MDSCs might be an early indicator of the incomplete RFA and subsequently a potential tumour relapse in NSCLC.

Check and mate to exosomal extracellular miRNA: new lesson from a new approach

MicroRNAs (miRNAs) are 19-24 nt single-stranded RNAs which regulate gene expression by sequence-specific targeting of corresponding mRNAs. Extracellular miRNAs have been consistently detected in all human body fluids, and were shown to be prominent non-invasive biomarkers for various diseases including cancer. Albeit biological function of cell-free miRNA remains questionable, some studies demonstrated that exosomes encapsulated extracellular miRNAs could mediate inter-cellular signaling. While others suggested that these miRNAs are mostly by-products of cellular activity and do not carry any significant biological function. This article aims to discuss the current theories of origin of extracellular miRNA, and to highlight recent application of a novel technique of micro-vesicles counting, that may challenge the existence of exosomal miRNA.

Titanium dioxide nanoparticles induce an adaptive inflammatory response and invasion and proliferation of lung epithelial cells in chorioallantoic membrane

Titanium dioxide nanoparticles (TiO2 NPs) studies have been performed using relatively high NPs concentration under acute exposure and limited studies have compared shape effects. We hypothesized that midterm exposure to low TiO2 NPs concentration in lung epithelial cells induces carcinogenic characteristics modulated partially by NPs shape. To test our hypothesis we synthesized NPs shaped as belts (TiO2-B) using TiO2 spheres (TiO2-SP) purchased from Sigma Aldrich Co. Then, lung epithelial A549 cells were low-exposed (10 µg/cm(2)) to both shapes during 7 days and internalization, cytokine release and invasive potential were determined. Results showed greater TiO2-B effect on agglomerates size, cell size and granularity than TiO2-SP. Agglomerates size in cell culture medium was 310 nm and 454 nm for TiO2-SP and TiO2-B, respectively; TiO2-SP and TiO2-B induced 23% and 70% cell size decrease, respectively, whilst TiO2-SP and TiO2-B induced 7 and 14-fold of granularity increase. NOx production was down-regulated (31%) by TiO2-SP and up-regulated (70%) by TiO2-B. Both NPs induced a transient cytokine release (IL-2, IL-6, IL-8, IL-4, IFN-γ, and TNF-α) after 4 days, but cytokines returned to basal levels in TiO2-SP exposed cells while TiO2-B induced a down-regulation after 7 days. Midterm exposure to both shapes of NPs induced capability to degrade cellular extracellular matrix components from chorioallantoic membrane and Ki-67 marker showed that TiO2-B had higher proliferative potential than TiO2-SP. We conclude that midterm exposure to low NPs concentration of NPs has an impact in the acquisition of new characteristics of exposed cells and NPs shape influences cellular outcome.

microRNA-124 negatively regulates TLR signaling in alveolar macrophages in response to mycobacterial infection

The emerging roles of microRNAs (miRNAs) in regulating immune responses have attracted increasing attention in recent years; and the alveolar macrophages (AMs) are the main targets of mycobacterial infection, which play a pivotal role in the pathogenesis of Mycobacterium tuberculosis infection. However, the immunoregulatory role of miRNAs in AMs has not been fully demonstrated. In this study, we find that miR-124 is up-regulated in the peripheral leukocytes of patients with pulmonary tuberculosis; furthermore, the expression miR-124 can be induced upon Mycobacterium bovis Bacillus Calmette-Guerin (BCG) infection in both RAW264.7 AM cells in vitro and murine AMs in vivo. Mechanistically, miR-124 is able to modulate toll-like receptor (TLR) signaling activity in RAW264.7 cells in response to BCG infection. In this regard, multiple components of TLR signaling cascade, including the TLR6, myeloid differentiation factor 88 (MyD88), TNFR-associated factor 6 and tumor necrosis factor-α are directly targeted by miR-124. In addition, both overexpression of TLR signaling adaptor MyD88 and BCG infection are able to augment miR-124 transcription, while MyD88 expression silenced by small interfering RNA dramatically suppresses miR-124 expression in AMs in vitro. Moreover, the abundance of miR-124 transcript in murine AMs of MyD88 deficient mice is significantly less than that of their wild-type or heterozygous littermates; and the BCG infection fails to induce miR-124 expression in the lung of MyD88 deficient mouse. These results indicate a negative regulatory role of miR-124 in fine-tuning inflammatory response in AMs upon mycobacterial infection, in part through a mechanism by directly targeting TLR signaling.

Potential survival markers in cancer patients undergoing chemotherapy

Due to the importance of the identification of chemotherapy outcome prognostic factors, we attempted to establish the potential of oxidative stress/DNA damage parameters such as prognostic markers. The aim of the study was to determine whether platinum derivative-based chemotherapy in cancer patients (n = 66) is responsible for systemic oxidatively damaged DNA and whether damage biomarkers, such as 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dG) and the modified base 8-oxo-7,8-dihydroguanine (8-oxo-Gua), in urine and DNA may be used as a prognostic factor for the outcome of chemotherapy. All the aforementioned modifications were analyzed using techniques involving high-performance liquid chromatography/electrochemical detection (HPLC/EC) or HPLC/gas chromatography-mass spectrometry (GC-MS). Among all the analyzed parameters, the significantly decreased levels of 8-oxo-Gua in urine collected from a subgroup of patients 24 h after the first infusion of the drug, as compared with the baseline levels, correlated with a significantly longer overall survival (OS) (60 months after therapy) than in the subgroup without any decrease of this parameter after therapy (median OS = 24 months, p = 0.007). Moreover, a significantly longer OS was also observed in a group with increased urine levels of 8-oxo-dG after chemotherapy (38.6 vs. 20.5 months, p = 0.03). The results of our study suggest that patients with decreased 8-oxo-Gua levels and increased 8-oxo-dG levels in urine 24 h after the first dose should be considered as better responders to the administered chemotherapy, with a lower risk of death. The conclusion may permit the use of these parameters as markers for predicting the clinical outcome of platinum derivative-based chemotherapy.

The effect of proinflammatory cytokines on IL-17RA expression in NSCLC

Interleukin-17 receptor (IL-17RA) is essential for proinflammatory cytokine IL-17-mediated pathogenesis of various tumors. IL-17RA is upregulated by some proinflammatory cytokines such as IL-21 and IL-15 and downregulated by IL-2, while the effect of IL-1β, IL-6, IL-8, TNF-α on IL-17RA expression in non-small cell lung caner (NSCLC) remains unknown. Our findings revealed that IL-17RA mRNA was increased in NSCLC tissues compared with the corresponding peritumor tissues (P = 0.0039) and high expression of IL-17RA protein in human NSCLC tissues was significantly associated with histological subtype, primary tumor size and clinical stages (P = 0.033, 0.033 and 0.011, respectively). IL-17RA mRNA expression was positively related to IL-1β, IL-6, IL-8, TNF-α mRNA expression (P = 0.013, 0.0001, 0.002 and 0.010 respectively) in NSCLC tissues. Furthermore, IL-1β, IL-6, IL-8, TNF-α upregulated IL-17RA mRNA and protein in A549 and H460 cells (all P < 0.05). It is suggested that IL-1β, IL-6, IL-8, TNF-α promoted IL-17RA expression in NSCLC and they may involve in IL-17RA signaling in NSCLC.

Autophagy inhibition by sustained overproduction of IL6 contributes to arsenic carcinogenesis

Chronic inflammation has been implicated as an etiologic factor in cancer, whereas autophagy may help preserve cancer cell survival but exert anti-inflammatory effects. How these phenomenas interact during carcinogenesis remains unclear. We explored this question in a human bronchial epithelial cell-based model of lung carcinogenesis that is mediated by subchronic exposure to arsenic. We found that sustained overexpression of the pro-inflammatory IL6 promoted arsenic-induced cell transformation by inhibiting autophagy. Conversely, strategies to enhance autophagy counteracted the effect of IL6 in the model. These findings were confirmed and extended in a mouse model of arsenic-induced lung cancer. Mechanistic investigations suggested that mTOR inhibition contributed to the activation of autophagy, whereas IL6 overexpression was sufficient to block autophagy by supporting Beclin-1/Mcl-1 interaction. Overall, our findings argued that chronic inflammatory states driven by IL6 could antagonize autophagic states that may help preserve cancer cell survival and promote malignant progression, suggesting a need to uncouple inflammation and autophagy controls to enable tumor progression.

Pomegranate extracts and cancer prevention: molecular and cellular activities

There is increased appreciation by the scientific community that dietary phytochemicals can be potential weapons in the fight against cancer. Emerging data has provided new insights into the molecular and cellular framework needed to establish novel mechanism-based strategies for cancer prevention by selective bioactive food components. The unique chemical composition of the pomegranate fruit, rich in antioxidant tannins and flavonoids has drawn the attention of many investigators. Polyphenol rich fractions derived from the pomegranate fruit have been studied for their potential chemopreventive and/or cancer therapeutic effects in several animal models. Although data from in vitro and in vivo studies look convincing, well designed clinical trials in humans are needed to ascertain whether pomegranate can become part of our armamentarium against cancer. This review summarizes the available literature on the effects of pomegranate against various cancers.

(5-Hydroxy-4-oxo-4H-pyran-2-yl)methyl 6-hydroxynaphthalene-2-carboxylate, a kojic acid derivative, inhibits inflammatory mediator production via the suppression of Syk/Src and NF-κB activation

Numerous derivatives of kojic acid have been synthesised to expand its immunopharmacological uses. Kojic acid is known to have anti-cancer, anti-inflammatory, and anti-melanogenesis effects. We found that (5-hydroxy-4-oxo-4H-pyran-2-yl)methyl 6-hydroxynaphthalene-2-carboxylate (MHNC) strongly suppressed the production of nitric oxide (NO) in an initial screening experiment. In this study, we explored the in vitro and in vivo anti-inflammatory activity of MHNC and its inhibitory mechanisms using lipopolysaccharide (LPS)-treated RAW264.7 cells and HCl/EtOH-treated ICR mice. MHNC dose-dependently diminished the secretion of nitric oxide (NO) and prostaglandin (PG)E2 in LPS-treated RAW264.7 cells. This compound also suppressed the upregulation of mRNA levels for the inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 genes. Additionally, the transcriptional activation of these genes was inhibited by MHNC through the suppression of the nuclear translocation of nuclear factor (NF)-κB subunits (p65 and p50), as determined by a luciferase reporter assay. Interestingly, MHNC treatment was found to suppress a series of upstream signalling cascades consisting of IκBα, AKT, PDK1, Src, and Syk for NF-κB activation. Furthermore, a direct enzyme assay with purified Src and Syk and luciferase assays using Src and Syk overexpression indicated that these enzymes were directly inhibited by MHNC. Finally, MHNC (20mg/kg) prevented inflammatory symptoms of the stomach in mice treated with HCl/EtOH by reducing phospho-IκBα levels. Taken together, our data suggest that MHNC may negatively modulate in vitro and in vivo inflammatory responses via the direct suppression of Syk/Src and NF-κB.

MUC1 in macrophage: contributions to cigarette smoke-induced lung cancer

Expression of the pro-oncogenic mucin MUC1 is elevated by inflammation in airway epithelial cells, but the contributions of MUC1 to the development of lung cancer are uncertain. In this study, we developed our finding that cigarette smoke increases Muc1 expression in mouse lung macrophages, where we hypothesized MUC1 may contribute to cigarette smoke-induced transformation of bronchial epithelial cells. In human macrophages, cigarette smoke extract (CSE) strongly induced MUC1 expression through a mechanism involving the nuclear receptor PPAR-γ. CSE-induced extracellular signal-regulated kinase (ERK) activation was also required for MUC1 expression, but it had little effect on MUC1 transcription. RNA interference-mediated attenuation of MUC1 suppressed CSE-induced secretion of TNF-α from macrophages, by suppressing the activity of the TNF-α-converting enzyme (TACE), arguing that MUC1 is required for CSE-induced and TACE-mediated TNF-α secretion. Similarly, MUC1 blockade after CSE induction through suppression of PPAR-γ or ERK inhibited TACE activity and TNF-α secretion. Conditioned media from CSE-treated macrophages induced MUC1 expression and potentiated CSE-induced transformation of human bronchial epithelial cells in a TNF-α-dependent manner. Together, our results identify a signaling pathway involving PPAR-γ, ERK, and MUC1 for TNF-α secretion induced by CSE from macrophages. Furthermore, our results show how MUC1 contributes to smoking-induced lung cancers that are driven by inflammatory signals from macrophages.