6-Gingerol Alleviates NNK-Induced Lung Carcinogenesis by Boosting Antioxidation and Reducing Inflammation

Licochalcone A reverses NNK-induced ectopic miRNA expression to elicit in vitro and in vivo chemopreventive effects

Lung cancer remains the leading cause of cancer-related mortality worldwide, with tobacco carcinogens such as 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) playing a central role in its pathogenesis. Chemoprevention through dietary or natural compounds offers a promising strategy to mitigate cancer risk. Published studies have indicated that ginger oil (GIO), a bioactive extract from ginger, possesses various bioactivities, suggesting its potential for cancer chemopreventive. In this study, we aimed to investigate the lung cancer chemopreventive potential of GIO. An NNK-induced lung cancer model in A/J mice was utilized to evaluate the preventive effect of GIO against lung cancer. Additionally, the potential mechanisms by which GIO might prevent NNK-induced lung cancer were assessed using molecular biology techniques combined with multi-omics. The results demonstrated that GIO decreased the number of lung tumors in the lungs of mice. Mechanistically, GIO exerts chemopreventive effects by modulating both the TLR4/NF-κB and PPARγ/NF-κB signaling axes, thereby suppressing downstream pro-inflammatory mediators. Furthermore, GIO modulates gut microbiota composition and its metabolites. Critically, its lung chemopreventive efficacy against NNK-induced lung carcinogenesis is partially dependent on microbiota-mediated regulation. Overall, these findings underscore the nutritional value of GIO as a diet-derived chemopreventive agent against lung cancer caused by tobacco carcinogens.

More than 90% of lung cancers are caused by cigarette smoke and air pollution, with polycyclic aromatic hydrocarbons (PAHs) as key carcinogens. In Xuanwei City of Yunnan Province, the lung cancer incidence is among the highest in China, attributed to smoky coal combustion-generated PAH pollution. Here, we screened for abnormal inflammatory factors in non-small cell lung cancers (NSCLCs) from Xuanwei and control regions (CR) where smoky coal was not used, and found that a chemokine CXCL13 was overexpressed in 63/70 (90%) of Xuanwei NSCLCs and 44/71 (62%) of smoker and 27/60 (45%) of non-smoker CR patients. CXCL13 overexpression was associated with the region Xuanwei and cigarette smoke. The key carcinogen benzo(a)pyrene (BaP) induced CXCL13 production in lung epithelial cells and in mice prior to development of detectable lung cancer. Deficiency in Cxcl13 or its receptor, Cxcr5, significantly attenuated BaP-induced lung cancer in mice, demonstrating CXCL13’s critical role in PAH-induced lung carcinogenesis.DOI: http://dx.doi.org/10.7554/eLife.09419.001

Present and Past Smoking History and Other Predisposing Factors in 100 Lung Cancer Patients

Lung cancer is a prevalent and very aggressive sickness that will likely claim 1.8 million lives by 2022, with an estimated 2.2 million additional cases expected worldwide. The goal of the current investigation was to determine whether petroleum ether extract of purslane leaf could be used to treat lung cancer induced by 4-(Methylnitrosamino)-1-(3-pyridyl)-1-buta-4 none (NNK) in rats. In the in vitro extract recorded, promising anticancer effects in A540 cell lines with IC50 were close to the reference drug, doxorubicin (14.3 and 13.8 μg/mL, respectively). A dose of 500 mg/kg/day orally for 20 weeks exhibited recovery effects on NNK-induced lung cancer with a good safety margin, where Intercellular Adhesion Molecule-1 (ICAM-1), the lung cancer biomarker, was significantly reduced by about 18.75% compared to cancer control. Purslane exhibited many anticancer mechanisms, including (i) anti-proliferation as a significant reduction in Ki67 level (20.42%), (ii) anti-angiogenesis as evident by a considerable decrease in Matrix metalloproteinase-9 (MMP-9) expression (79%), (iii) anti-inflammation as a remarked decline in Insulin-like growth factor 1 (IGF-1) expression (62%), (iv) pro-apoptotic effect as a significant activation in Forkhead box protein O1 (FOXO1) expression (262%), and (v) anti-oxidation as remarkable activation on antioxidant biomarkers either non-enzymatic or enzymatic concurrent with considerable depletion on oxidative stress biomarker, in comparison to cancer control. The histopathological examination revealed that Purslane extract showed markedly improved tissue structure and reduced pathological changes across all examined organs caused by NNK. The anti-lung cancer effect exhibited by the extract may be linked to the active ingredients of the extract that were characterized by LC-MS, such as α-linolenic acid, linoleic acid, palmitic acid, β-sitosterol, and alkaloids (berberine and magnoflorine).

Smoking is a major cause of lung cancer, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is one of the most important carcinogens in cigarette smoke. NNK modulates the expression of peroxiredoxin (Prdx) I in lung cancer. Prdx1 is upregulated in lung squamous cell carcinoma and lung adenocarcinoma, and considered a potential biomarker for lung cancer. The current article reviewed the role and regulatory mechanisms of Prdx1 in NNK-induced lung cancer cells. Prdx1 protects erythrocytes and DNA from NNK-induced oxidative damage, prevents malignant transformation of cells and promotes cytotoxicity of natural killer cells, hence suppressing tumor formation. In addition, Prdx1 has the ability to prevent NNK-induced lung tumor metabolic activity and generation of large amount of reactive oxygen species (ROS) and ROS-induced apoptosis, thus promoting tumor cell survival. In contrast to this, Prdx1, together with NNK, can promote the epithelial-mesenchymal transition and migration of lung tumor cells. The signaling pathways associated with NNK and Prdx1 in lung cancer cells have been discussed in present review; however, numerous potential pathways are yet to be studied. To develop novel methods for treating NNK-induced lung cancer, and improve the survival rate of patients with lung cancer, further research is needed to understand the complete mechanism associated with NNK.

Sec62 Bridges the Gap from 3q Amplification to Molecular Cell Biology in Non–Small Cell Lung Cancer

Lung cancer is a common malignant tumor of the lung. To explore the molecular mechanism of the occurrence and development of lung cancer is a hot topic in current research. Cyclic RNA D1 (CircCCND1) is highly expressed in lung cancer and may be a potential target for the treatment of lung cancer. The aim of this study was to investigate the effect of CircCCND1 on the malignant biological behaviors of lung cancer cells by regulating the miR-340-5p/transforming growth factor β-induced factor homeobox 1 (TGIF1) axis. The expression of CircCCND1, miR-340-5p, and TGIF1 mRNA in human normal lung epithelial cells BEAS-2B and human lung cancer H446 cells were detected. H446 cells cultured in vitro were randomly divided into control group, CircCCND1 siRNA group, miR-340-5p mimics group, negative control group, and CircCCND1 siRNA+miR-340-5p inhibitor group. Cell proliferation, mitochondrial membrane potential, apoptosis, migration, and invasion were detected, and the expressions of CircCCND1, miR-340-5p, TGIF1 mRNA, BCL2-associated X protein (Bax), cleaved Caspase-3, N-cadherin, E-cadherin, and TGIF1 proteins in each group were detected. The targeting relationship of miR-340-5p with CircCCND1 and TGIF1 was verified. Compared with BEAS-2B cells, CircCCND1 and TGIF1 mRNA were increased in H446 cells, and miR-340-5p expression was decreased (P<0.05). Knocking down CircCCND1 or up-regulating the expression of miR-340-5p inhibited the proliferation, migration and invasion of H446 cells, decreased the expression of TGIF1 mRNA and TGIF1 protein, and promoted cell apoptosis. Down-regulation of miR-340-5p could antagonize the inhibitory effect of CircCCND1 knockdown on the malignant biological behavior of H446 lung cancer cells. CircCCND1 may target the down-regulation of miR-340-5p, and miR-340-5p may target the down-regulation of TGIF1. Knocking down CircCCND1 can inhibit the malignant behaviors of lung cancer H446 cells, which may be achieved through the regulation of miR-340-5p/TGIF1 axis.

High-risk human papillomavirus (HPV)16/18 infection in the development of lung cancer has previously been identified, and fragile histidine triad (FHIT) loss and p53 mutation are frequently observed in the disease. However, the association between these factors has not been well studied. The present study aimed to further investigate the significance of HPV infection, FHIT loss and p53 mutations in the development of lung cancer and their possible associations. DNA was extracted from paraffin-embedded specimens from 88 cases of squamous cell carcinoma (SCC), 56 of adenocarcinoma (AC), 36 of small cell lung carcinoma (SCLC) and 110 non-cancer control cases of lung neoplasms. The prevalence of HPV infection was determined by polymerase chain reaction analysis, and FHIT loss and p53 mutations were detected by immunohistochemistry. The χ2, Fisher's exact and Pearson correlation tests were applied for statistical analysis. The results of the present study demonstrated that HPVL1 (the major capsid protein of HPV), HPV16 and HPV18 infection were more prevalent in the lung cancer samples compared with the non-cancer controls (all P<0.001). FHIT loss occurred more frequently in the lung cancer samples (44.44%) compared with the non-cancer controls (7.25%) (P<0.001). FHIT loss in the HPVL1-positive group was significantly increased compared with the HPVL1-negative group in the lung cancer cases and the non-cancer controls (P<0.05). In the lung cancer cases, the p53 mutation rates in the HPVL1- and HPV16/18-positive groups were significantly increased compared with the HPVL1- and HPV16/18-negative groups (P<0.05). In the 180 lung cancer cases, the coexistence rate of FHIT loss and a history of smoking was 38.33% (69/180; Pearson contingency coefficient of r=0.318; P<0.001). FHIT loss and p53 mutation exhibited a synergistic effect on HPV-associated lung cancer (Pearson contingency coefficient r=0.357, P<0.001). The present study demonstrated that FHIT loss may be important in the occurrence of lung cancer, particularly in lung SCCs. FHIT loss may therefore be used as an early indicator for lung cancer, particularly for patients with a history of smoking. HPV infection in lung tumorigenesis may, at least in part, be mediated through FHIT loss. FHIT loss and p53 mutation may coordinate together in the development of HPV-associated lung cancer, and accelerate the occurrence and development of lung cancer.

Despite the identification of several preventive agents and strategies, prevention of lung cancer, especially in smokers who are at high risk, is still largely unattained. 1,4-Phenylenebis(methylene)selenocyanate (p-XSC) has been shown to inhibit tobacco carcinogen NNK induced lung cancer development in several animal models. It metabolizes through the formation of active bis-selenol (p-XSeH) along with the release of poisonous hydrogen cyanide (HCN). Nevertheless, the HCN released upon metabolism of p-XSC to form active metabolite p-XSeH, pose a serious challenge its clinical use in a chemopreventive set up where a continuous intake is required for healthy individuals over a longer period of time. Recently, we developed a hybrid agent, p-XS-Asp, linking p-XSe- to commonly used non-steroidal anti-inflammatory drug, aspirin (Asp), which has been shown to be preventive of lung, and colorectal cancer. We hypothesized that p-XS-Asp would cleave in vivo to release the active p-XSeH, not releasing undesired HCN but the aspirin, thus making the compound less toxic and more potent than p-XSC or aspirin alone. Our studies have shown p-XS-Asp to be orally bioavailable and a highly effective lung cancer chemopreventive agent both in vitro and in animal studies. Elemental selenium (Se) analysis of plasma, lung, and liver tissue in orally fed mice showed that the level of Se significantly higher for p-XS-Asp than p-XSC, denoting a better bioavailability profile for p-XS-Asp. Dietary p-XS-Asp inhibited both O-6 methyl guanine and pyridoxobutyl (pob) DNA adducts, in lung and liver of A/J mice, more effectively than p-XSC. Particularly, in the lung, the inhibition of O-6 methyl guanine adducts, which are critical for A/J mouse lung tumor development, were more than 2 times higher than p-XSC. In a NNK-induced lung cancer A/J mouse model, p-XS-Asp at doses of 15 ppm and 7.5 ppm Se, showed a significantly marked decrease in percentage of lung tumor incidence of 50% and 87%, as compared to p-XSC (79% and 100%), respectively; NNK-control showed an 100% tumor incidence. In addition, the multiplicity for p-XS-Asp was 0.87 and 1.93 tumors/mouse as compared with NNK-control (11.53 tumors/mouse) and p-XSC (1.66 and 4.10 tumors/mouse, respectively) at the two doses tested. Notably, blood and tissue analyses showed no signs of systemic toxicity for the p-XS-Asp fed group. In conclusion, p-XS-Asp, is less toxic and more effective chemopreventive agent than p-XSC and is a promising candidate to future clinical evaluation. Citation Format: Daniel Plano, Cesar Aliaga, Manoj K. Pandey, Arunangshu Das, Timothy K. Cooper, Shantu Amin, Arun K. Sharma. Pre-clinical chemopreventive efficacy of a novel hybrid p-XSC-aspirin compound in a NNK-induced A/J mouse lung cancer model. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2139. doi:10.1158/1538-7445.AM2014-2139

Elevated blood levels of low-density lipoprotein cholesterol are a major cardiovascular risk factor, and cholesterol-lowering drugs are among the most prescribed drugs worldwide. Cancer is the second leading cause of death after cardiovascular diseases. The relationship between cancer development and statins intake is controversial, and there are no clear studies in Lebanon and the Middle East concerning this topic. Hence, our study aimed to search for any possible association of statin intake as well as other medications (proton pump inhibitors [PPI], metformin, Aspirin, Angiotensin-Converting Enzyme inhibitors, and fenofibrate) with lung, colorectal cancer (CRC), and bladder cancer development in the Lebanese population. A retrospective study was performed on 709 subjects divided into 2 main groups: control (no cancer ± statin intake), and cases (either lung, or colorectal, or bladder cancer ± statin intake). Collected data included the age and gender of the patient, socioeconomic status, presence of cardiovascular disease and comorbidities, cancer risk factors, and the intake type, dose, and duration of statins. Bivariate, multivariate, and binary logistic analyses were enrolled. Out of 709 participants, 63.2% were males and 75% were cancer-positive (24.1%: lung cancer, 26.7%: CRC, 24.1%: bladder cancer). The overall intake of statins was not shown to significantly affect cancer development. However, a duration-response relationship was established between Simvastatin and lung cancer (odds ratio [OR]=1.208) as well as bladder cancer (OR=1.189). No significant association was found between each statin and CRC. Although PPIs intake was associated with a possibly harmful effect on lung cancer development (OR=3.42), it revealed a protective association with CRC development (OR=0.38). Other risk factors such as smoking and age were strongly associated (harmful) with lung and bladder cancer development. Physical inactivity and a family history of CRC were each associated with a harmful effect on CRC development. A harmful association with the development of lung and bladder cancer was found with the increasing duration of intake of Simvastatin. Other drugs such as PPIs and specific risk factors were also associated negatively or positively with the development of these 3 cancers. These findings should be validated by further investigations to guide clinicians on optimal treatment options for their patients.

Lung cancer is the most frequent cancer type and the leading cause of tumor-associated deaths worldwide. TP53 is an important tumor suppressor gene and is frequently inactivated in lung cancer. E3 ligases targeting p53, such as MDM2, are involved in the development of lung cancer. The E3 ligase HUWE1, which targets many tumor-associated proteins including p53, has been reported to be highly expressed in lung cancer; however, its role in lung tumorigenesis is unclear.Methods: The expression of HUWE1 and p53 in lung cancer cells was modulated and the phenotypes were assessed by performing soft agar colony forming assays, cell cycle analysis, BrdU incorporation assays, and xenograft tumor growth assays. The effect on tumorigenesis in genetically-engineered mice was also analyzed. The mechanism through which HUWE1 sustained lung cancer cell malignancy was confirmed by western blotting. HUWE1 expression in clinical lung cancer was identified by immunohistochemistry and validated by analyzing lung adenocarcinoma and lung squamous carcinoma samples from the Cancer Genome Atlas (TCGA) database. Finally, we assessed the association between HUWE1 expression and patient outcome using online survival analysis software including survival information from the caBIG, GEO, and TCGA database.Results: Inactivation of HUWE1 in a human lung cancer cell line inhibited proliferation, colony-forming capacity, and tumorigenicity. Mechanistically, this phenotype was driven by increased p53, which was due to attenuated proteasomal degradation by HUWE1. Up-regulation of p53 inhibited cancer cell malignancy, mainly through the induction of p21 expression and the down-regulation of HIF1α. Huwe1 deletion completely abolished the development of EGFRVIII-induced lung cancer in Huwe1 conditional knockout mice. Furthermore, survival analysis of lung cancer patients showed that increased HUWE1 expression is significantly associated with worse prognosis.Conclusion: Our data suggest that HUWE1 plays a critical role in lung cancer and that the HUWE1-p53 axis might be a potential target for lung cancer therapy.

BackgroundThe cancer death rate escalated during 20th century. In South Korea, lung cancer is expected to contribute 12,736 deaths in men, the highest amount among all cancers. Several risk factors may increase the chance to acquiring lung cancer, with mostly related to exogenous compounds found in cigarette smoke and synthetic manufacturing materials. As the mortality rate of lung cancer increases, deeper understanding is necessary to explore risk factors that may lead to this malignancy. In this regard, this study aims to apply high resolution metabolomics (HRM) using LC-MS to detect significant compounds that might contribute in inducing lung cancer and find the correlation of these compounds to the subjects’ smoking habit.MethodsThe comparison was made between healthy control and lung cancer groups for metabolic differences. Further analyses to determine if these differences are related to tobacco-induced lung cancer (past-smoker control vs. past-smoker lung cancer patients (LCPs) and non-smoker control vs. current-smoker LCPs) were selected. The univariate analysis was performed, including a false discovery rate (FDR) of q = 0.05, to determine the significant metabolites between the analyses. Hierarchical clustering analysis (HCA) was done to discriminate metabolites between the control and case subjects. Selected compounds based on significant m/z features of human serum then experienced MS/MS examination, showing that for many m/z, the patterns of ion dissociation matched with standards. Then, the significant metabolites were identified using Metlin database and features were mapped on the human metabolic pathway mapping tool of the Kyoto Encyclopedia of Genes and Genomes (KEGG).ResultsUsing metabolomics-wide association studies, metabolic changes were observed among control group and lung cancer patients. Bisphenol A (211.11, [M + H-H2O]+), retinol (287.23, [M + H]+) and L-proline (116.07, [M + H]+) were among the significant compounds found to have contributed in the discrimination between these groups, suggesting that these compounds might be related in the development of lung cancer. Retinol has been seen to have a correlation with smoking while both bisphenol A and L-proline were found to be unrelated.ConclusionsTwo potential biomarkers, retinol and L-proline, were identified and these findings may create opportunities for the development of new lung cancer diagnostic tools.Electronic supplementary materialThe online version of this article (doi:10.1186/s12931-016-0419-3) contains supplementary material, which is available to authorized users.

Incorporating genomic data into multivariate risk models for lung cancer

Critical to mechanisms of chemical carcinogenesis and the design of chemopreventive strategies is whether procarcinogen bioactivation in an extrahepatic target tissue (e.g., the lung) is essential for tumor formation. This study aims to develop a mouse model capable of revealing the role of pulmonary microsomal cytochrome P450 (P450)-mediated metabolic activation in xenobiotic-induced lung cancer. A novel triple transgenic mouse model, with the NADPH-P450 reductase (Cpr) gene deleted in a lung-specific and doxycycline-inducible fashion (lung-Cpr-null), was generated. CPR, the obligate electron donor for microsomal P450 enzymes, is essential for the bioactivation of many procarcinogens. The lung-Cpr-null mouse was studied to resolve whether pulmonary P450 plays a major role in 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced lung cancer by producing carcinogenic metabolites in the target tissue. A liver-Cpr-null mouse was also studied to test whether hepatic P450 contributes predominantly to systemic clearance of NNK, thereby decreasing NNK-induced lung cancer. The numbers of NNK-induced lung tumors were reduced in the lung-Cpr-null mice but were increased in the liver-Cpr-null mice, relative to wild-type control mice. Decreased lung tumor multiplicity in the lung-Cpr-null mice correlated with reduced lung O6-methylguanine adduct levels, without decreases in NNK bioavailability, consistent with decreased NNK bioactivation in the lung. Moreover, lung tumors in lung-Cpr-null mice were positive for CPR expression, indicating that the tumors did not originate from Cpr-null cells. Thus, we have confirmed the essential role of pulmonary P450-mediated metabolic activation in NNK-induced lung cancer, and our mouse models should be applicable to studies on other procarcinogens that require P450-mediated metabolic activation.