Induced Lung Cancer Research Articles

Label-free quantitative proteomic analysis of benzo(a)pyrene-transformed 16HBE cells serum-free culture supernatant and xenografted nude mice sera

To screen potential biomarkers of benzo(a)pyrene (BaP)-induced lung cancer, the proteomic profiles of BaP-transformed 16HBE cell line T-16HBE-C1 cells serum-free culture supernatant and xenografted nude mice sera were compared with those of 16HBE group by utilizing label-free quantitative proteomic strategy. By employing nano-LC−MS/MS technology followed by MaxQuant and Perseus processing, 489 differentially expressed proteins were identified between T-16HBE-C1 and 16HBE cells serum-free culture supernatant, and 49 significantly up-regulated proteins were identified in T-16HBE-C1 xenografted nude mice sera. Three proteins neuropilin-2 (NRP2), clusterin (CLU) and A-kinase anchor protein 12 (AKAP12) were up-regulated in the serum-free culture supernatant of T-16HBE-C1 cells. These 3 human proteins were present in the sera of nude mice xenografted with T-16HBE-C1 cells, but were undetectable in mice xenografted with 16HBE cells. The proteomic results of NRP2 and AKAP12 were confirmed by Western blotting and enzyme-linked immunosorbent assays, respectively. Moreover, the serum NRP2 levels were significantly elevated at the 4th day after tumor cell implantation and showed good positive correlation with tumor growth characterized by tumor volume. In conclusion, serum NRP2, CLU and AKAP12 could be potential biomarkers of BaP-induced lung cancer. The proteomic results will gain deeper insights into the mechanisms of BaP-induced carcinogenesis.

Inhalation cancer risk assessment of hexavalent chromium based on updated mortality for Painesville chromate production workers.

The exposure-response for hexavalent chromium (Cr(VI))-induced lung cancer among workers of the Painesville Ohio chromate production facility has been used internationally for quantitative risk assessment of environmental and occupational exposures to airborne Cr(VI). We updated the mortality of 714 Painesville workers (including 198 short-term workers) through December 2011, reconstructed exposures, and conducted exposure-response modeling using Poisson and Cox regressions to provide quantitative lung cancer risk estimates. The average length of follow-up was 34.4 years with 24,535 person-years at risk. Lung cancer was significantly increased for the cohort (standardized mortality ratio (SMR)=186; 95% confidence interval (CI) 145–228), for those hired before 1959, those with >30-year tenure, and those with cumulative exposure >1.41 mg/m3-years or highest monthly exposures >0.26 mg/m3. Of the models assessed, the linear Cox model with unlagged cumulative exposure provided the best fit and was preferred. Smoking and age at hire were also significant predictors of lung cancer mortality. Adjusting for these variables, the occupational unit risk was 0.00166 (95% CI 0.000713–0.00349), and the environmental unit risk was 0.00832 (95% CI 0.00359–0.0174), which are 20% and 15% lower, respectively, than values developed in a previous study of this cohort.

PIK3CA(H1047R) Accelerates and Enhances KRAS(G12D)-Driven Lung Tumorigenesis.

KRAS-activating mutations drive human non-small cell lung cancer and initiate lung tumorigenesis in genetically engineered mouse (GEM) models. However, in a GEM model of KRAS(G12D)-induced lung cancer, tumors arise stochastically following a latency period, suggesting that additional events are required to promote early-stage tumorigenic expansion of KRAS(G12D)-mutated cells. PI3Kα (PIK3CA) is a direct effector of KRAS, but additional activation of PI3'-lipid signaling may be required to potentiate KRAS-driven lung tumorigenesis. Using GEM models, we tested whether PI3'-lipid signaling was limiting for the promotion of KRAS(G12D)-driven lung tumors by inducing the expression of KRAS(G12D) in the absence and presence of the activating PIK3CA(H1047R) mutation. PIK3CA(H1047R) expression alone failed to promote tumor formation, but dramatically enhanced tumorigenesis initiated by KRAS(G12D). We further observed that oncogenic cooperation between KRAS(G12D) and PIK3CA(H1047R) was accompanied by PI3Kα-mediated regulation of c-MYC, GSK3β, p27(KIP1), survivin, and components of the RB pathway, resulting in accelerated cell division of human or mouse lung cancer-derived cell lines. These data suggest that, although KRAS(G12D) may activate PI3Kα by direct biochemical mechanisms, PI3'-lipid signaling remains rate-limiting for the cell-cycle progression and expansion of early-stage KRAS(G12D)-initiated lung cells. Therefore, we provide a potential mechanistic rationale for the selection of KRAS and PIK3CA coactivating mutations in a number of human malignancies, with implications for the clinical deployment of PI3' kinase-targeted therapies.

Naringenin ameliorates inflammation and cell proliferation in benzo(a)pyrene induced pulmonary carcinogenesis by modulating CYP1A1, NFκB and PCNA expression

Lung cancer is the major cause of cancer-related mortality and is a growing economic burden worldwide. Chemoprevention has emerged as a very effective preventive measure against carcinogenesis and several bioactive compounds in diet have shown their cancer curative potential on lung cancer. Naringenin (NRG), a predominant flavanone found in citrus fruits has been reported to possess anti-oxidative, anti-inflammatory and anti-proliferative activity in a wide variety of cancer. The aim of the present study is to divulge the chemopreventive nature of NRG against benzo(a)pyrene (B[a]P) induced lung carcinogenesis in Swiss albino mice. Administration of B[a]P (50mg/kg, p.o.) to mice resulted in increased lipid peroxidation (LPO), proinflammatory cytokines (TNF-α, IL-6 and IL-1β) with subsequent decrease in activities of tissue enzymic antioxidants (SOD, CAT, GPx, GR, GST) and non-enzymic antioxidants (GSH and Vit-C). Treatment with NRG (50mg/kg body weight) significantly counteracted all these alterations thereby showing potent anti-cancer effect in lung cancer. Moreover, assessment of protein expression by immunoblotting and mRNA expression by RT-PCR revealed that NRG treatment effectively negates B[a]P-induced upregulated expression of CYP1A1, PCNA and NF-κB. Further, the antiproliferative effect of NRG was confirmed by histopathological analysis and PCNA immunostaining in B[a]P induced mice which showed increased PCNA expression that was restored upon NRG administration. Overall, these findings substantiate the chemopreventive potential of NRG against chemically induced lung cancer in mice.

Toxins Secreted by Bacillus Isolated from Lung Adenocarcinomas Favor the Penetration of Toxic Substances.

The aim was to explore the eventual role of bacteria in the induction of lung cancer by smoking habits. Viable bacteria closely related to the genus Bacillus were detected at high frequencies in lung-cancer biopsies. Similar, if not identical, microbes were isolated from cigarettes and in smog. Bacteria present in cigarettes could be transferred to a physiological solution via a “smoker” device that mimicked their potential transfer during smoking those bacteria produce exotoxins able to open transmembrane pores. These channels can be used as a way to penetrate cells of benzopyrenes and other toxic substances present in tobacco products. We hypothesize that Bacillaceae present in tobacco play a key role in the development of lung cancer.

Antiproliferative and antioxidant potential of hesperetin against benzo(a)pyrene-induced lung carcinogenesis in Swiss albino mice

Lung cancer is the foremost cause of cancer mortality and is a growing economic burden worldwide. Chemoprevention, employing the use of natural, dietary or synthetic agents has become an appealing strategy to combat the increasing cases of cancers worldwide. The present study was designed to investigate the mechanism-based chemopreventive nature of hesperetin (HSP) against B[a]P induced lung carcinogenesis in Swiss albino mice. We analyzed the chemopreventive potential of HSP by estimating the status of lipid peroxidation (LPO), enzymic (SOD, CAT, GPx, GR, and GST), nonenzymic antioxidants (GSH, Vit C and Vit E), proinflammatory cytokine (TNF-α), western blotting (CYP1A1, PCNA, Nrf2 and NF-κB expression) and histopathology of lung tissues of control and experimental mice. Administration of B[a]P (50 mg/kg, p.o.) resulted in an increase in lung weight, LPO with concomitant decrease in body weight, enzymic (SOD, CAT, GPx, GR, and GST) and non-enzymic (GSH, Vit C and Vit E) antioxidants. Histological examination of lungs revealed severe alveolar and bronchiolar damages in B[a]P-induced mice. Further, elevated levels of TNF-α along with activated expression of NF-κB, PCNA and CYP1A1, and downregulation of Nrf2 was observed in B[a]P intoxicated animals. Pre- and post-treatment with HSP effectively suppressed B[a]P induced lung carcinoma and the associated preneoplastic lesions by alleviating LPO, modulating antioxidants and decreasing the expression of NF-κB, PCNA and CYP1A1. These findings demonstrate that HSP possesses a potential chemopreventive activity against B[a]P induced lung cancer and this is attributed to its free radical scavenging, antioxidant, anti-inflammatory and antiproliferative properties.

Antiproliferative and Chemopreventive effect of Annona muricata Linn. on Ehrlich ascites carcinoma and Benzo[a]pyrene induced lung carcinoma

Annona muricata Linn. also called “Soursop” or “Sharp Sharp” is traditionally used in treatment of cancer. There are many claims that Annona muricata L. can kill cancer cells, since its leaves, seeds and fruits contain active compound called annonaceous acetogenins. This research was aimed to evaluate the antiproliferative and chemopreventive effect of Annona muricata L. leaf extract against Ehrlich ascites carcinoma and benzo[a]pyrene induced lung carcinoma. In Ehrlich ascites carcinoma model, the tumor bearing mice treated with methanol extract of Annona muricata leaves 200 mg/kg and 400 mg/kg once daily orally started 24 h after inoculation significantly reduced the viable cell count. The dose level of 400 mg/kg showed a significant increase in non-viable count with a significant decrease in body weight of animals compared to EAC control animals. The haematological parameters were reverted to more or less normal levels in animals treated with extract 400 mg/kg. In benzo[a]pyrene induced lung cancer model, treatment with extract started 1 week before benzo[a]pyrene induction and continued once daily for 16 weeks, effectively suppressed lung cancer. There was a significant increase in weight gain during experimental period with a significant decrease in relative lung weight and serum cancer marker - carcinoembryonic antigen at the end of experimental period. Gross morphology of lung also appeared near normal to lung of normal animals. Moreover, with reference to lipid peroxidation and antioxidant system, Annona muricata leaf extract decreased the extent of lipid peroxidation with concomitant increase in activities of superoxide dismutase, catalase and reduced glutathione compared to lung cancer bearing untreated animals. It was observed that extract 400 mg/kg showed a significant protection against benzo[a]pyrene induced carcinogenesis. Histological examination of lung tissue too correlated with morphological and biochemical observations. Our data suggest that, the potential anti-proliferative and chemopreventive action of Annona muricata leaves might be due to cytotoxic mechanism against cancer cells in the pathway of apoptosis and inhibition of cell cycle. Furthermore, our in-vitro investigation on extract showed a potent free radical scavenging activity. An additional antioxidant property of Annona muricata leaves might be responsible for chemoprevention by stabilizing all the components of antioxidant defense which were disturbed during benzo[a]pyrene induced oxidative damage.

Chemopreventive effect of chrysin, a dietary flavone against benzo(a)pyrene induced lung carcinogenesis in Swiss albino mice

Chemoprevention is considered as one of the most promising and realistic approaches in the prevention of lung cancer. Chrysin, a naturally occurring dietary flavone widely found in Passiflora family of plants and honey, has been studied extensively for its chemopreventive properties. The objective of present study is to divulge the chemopreventive role of chrysin against benzo(a)pyrene [B(a)P] induced lung carcinogenesis in Swiss albino mice. B(a)P was administered orally (50mg/kg body weight) twice a week for four weeks to induce lung cancer in mice. The body weight, lung weight, tumor incidence, lipid peroxidation, carcinoembryonic antigen, enzymatic antioxidants (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase) and non-enzymatic antioxidants (reduced glutathione, vitamin E and vitamin C) were estimated. Further, histopathological analysis of lung tissue and western blotting analysis of PCNA, COX-2 and NF-κB were also carried out. Administration of B(a)P resulted in increased lipid peroxides and carcinoembryonic antigen with concomitant decrease in the levels of both enzymatic antioxidants and non-enzymatic antioxidants. Chrysin treatment (250mg/kg body weight) significantly attenuated all these changes thereby showing potent anti lung cancer effect. Further, the anticancer effect of chrysin was confirmed by histopathology of lungs, and immunoblotting analysis of PCNA, COX-2 and NF-κB, where chrysin supplementation downregulated the expression of these proteins and maintained cellular homeostasis. Overall, these findings confirm the chemopreventive potential of chrysin against B(a)P induced lung cancer in Swiss albino mice.

Effects of Physalis peruviana L on Toxicity and Lung Cancer Induction by Nicotine Derived Nitrosamine Ketone in Rats.

Nicotine-derived nitrosamine ketone (NNK) is considered a key tobacco smoke carcinogen inducing lung tumors. Physalis peruviana L (harankash) is considered one plant with marked health benefits. This study aimed to evaluate Physalis peruviana L effect on the toxic effect of NNK induced lung cancer in the rats by using pulmonary histopathological, immunohistochemical and DNA flow cytometric analyses. Sixty adult male rats were divided into four groups, each consisting of fifteen animals. The first group received saline, the second received two successive toxic doses of NNK only while the third received two successive toxic doses of NNK with a single daily dose of Physalis peruviana L. The fourth group received a single daily dose of Physalis peruviana L only. Toxic doses of NNK induced hyperplasia and adenocarcinoma in the lung and positive immunoreactivity for Ki-67 and p53 staining with disturbance of the lung DNA content. Administration of Physalis peruviana L with NNK led to a mild pulmonary hyperplasia and weak expression of Ki-67 and p53 with an improvement in the lung DNA content. Physalis peruviana L may protect against NNK induced lung carcinogenesis due to its antioxidant and anti-proliferative effects.

Late radiation toxicity in Hodgkin lymphoma patients: proton therapy's potential.

In 2010, all young patients treated for intrathoracic Hodgkin lymphoma (HL) at one of 10 radiotherapy centers in the province of Quebec received 3D conformal photon therapy. These patients may now be at risk for late effects of their treatment, notably secondary malignancies and cardiac toxicity. We hypothesized that more complex radiotherapy, including intensity‐modulated proton therapy (IMPT) and possibly IMRT (in the form of helical tomotherapy (HT)), could benefit these patients. With institutional review board approval at 10 institutions, all treatment plans for patients under the age of 30 treated for HL during a six‐month consecutive period of 2010 were retrieved. Twenty‐six patients were identified, and after excluding patients with extrathoracic radiation or treatment of recurrence, 20 patients were replanned for HT and IMPT. Neutron dose for IMPT plans was estimated from published measurements. The relative seriality model was used to predict excess risk of cardiac mortality. A modified linear quadratic model was used to predict the excess absolute risk for induction of lung cancer and, in female patients, breast cancer. Model parameters were derived from published data. Predicted risk for cardiac mortality was similar among the three treatment techniques (absolute excess risk of cardiac mortality was not reduced for HT or IMPT (p>0.05,p>0.05) as compared to 3D CRT). Predicted risks were increased for HT and reduced for IMPT for secondary lung cancer (p<0.001,p<0.001) and breast cancers (p<0.001,p<0.001) as compared to 3D CRT.PACS numbers: 87.55.dh, 87.55.dk

17-Allylamino-17-Demethoxygeldanamycin and the Enhancement of PS-341-Induced Lung Cancer Cell Death by Blocking the NF-κB and PI3K/Akt Pathways.

PS-341 is a highly selective and potent proteasome inhibitor that is cytotoxic to various types of cancer. However, no objective response was seen in a clinical trial with PS-341 as a single agent in non-small cell lung cancer. Its antitumor activity is limited by the simultaneously activated antiapoptosis pathway. Recently, PS-341-induced NF-κB activation via IκBα degradation has been suggested to be one of its antiapoptotic effects. In this study, we investigated the effects of a combined application of the heat shock protein (Hsp) 90 inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG) with PS-341 in lung cancer cells. Hsp90 inhibition with 17-AAG was effective in enhancing PS-341-induced lung cancer cell death in vitro and in vivo. 17-AAG pretreatment induced the degradation of upstream regulators of IκB, IL-1R-associated kinase-1 (IRAK-1), and IκB kinases (IKKs), dose and time dependently, which resulted in blocking of PS-341-induced IκBα degradation, p65 nuclear translocation, transcriptional activity, and NF-κB-regulated antiapoptotic gene expressions such as COX-2. The concentrations of 17-AAG used for combinatorial treatment with PS-341 did not change cell viability or the activity of proteasome complex. Moreover, 17-AAG pretreatment decreased the level of phsophorylated Akt at serine 473 residue and suppressed active Akt-dependent inactivation of glycogen synthase kinase 3β. 17-AAG mediated the dissociation of its client proteins (IRAK-1, IKKs, and Akt) from the Hsp90 complex. As a result, it induced degradation of target proteins. Our results suggest that the combination of 17-AAG and PS-341 could be an effective anticancer therapy that overcomes the limited effects of PS-341.

Alpha-1 Antitrypsin Deficiency and Lung Cancer Risk: A Case-Control Study in Never-Smokers

Never-smokers comprise up to 25% of all lung cancer cases. They could have different molecular pathways for lung cancer induction compared with smokers. Alpha-1 antitrypsin (AAT) deficiency is a hereditary trait whose main characteristic is early onset of lung emphysema. Our aim is to know if AAT-deficient carriers have a higher risk of lung cancer in a study performed exclusively in never-smokers. We designed a multicentre hospital-based case-control study, which included incident never-smoking lung cancer cases. Controls were never-smokers attending nonmajor surgery at the participating hospitals. Controls were frequency matched on age and gender with cases. We determined AAT variants (alleles S and Z) through polymerase chain reaction. Two hundred and twelve cases and 318 controls were included. PiSS individuals showed a lung cancer risk of 4.64 (95% confidence interval: 1.08-19.92) compared with those with normal genotype (PiMM). When the analysis was restricted to women, the risk for PiSS increased to 7.58 (95% confidence interval: 1.40-40.87). This risk for homozygous SS was even higher for individuals exposed to environmental tobacco smoke (greater than 20 years). The presence of other alleles did not show any effect on lung cancer risk. Never smoking SS homozygous individuals pose an increased risk of lung cancer. The risk is higher for individuals exposed to environmental tobacco smoke.

Exposure To Radon And The Risk Of Lung Cancer By Histologic Group Among Canadian Uranium Miners

Background: Underground uranium mining and milling was conducted in Ontario from 1954 to 1996. This study is an updated analysis of cancer incidence among male members of the Ontario Uranium Miner's Cohort exposed to radon daughters. Methods: The cohort was created using radon exposure and work history data collected during a government mandated chest x-rays program and by Canada's National Dose Registry. It consists of mine and mill workers who worked at least one week, with national mortality (1954-2007) and tumor registry (1969-2005) follow-up. Histologic groups were based on ICD-O-3; squamous cell carcinoma (SqCC), adenocarcinomas (ADC), small cell carcinoma (SmCC), large cell carcinoma (LCC), and other. Poisson regression was used to estimate relative risks (RRs) and their 95% confidence intervals (CIs) with levels of cumulative radon exposure. Results: Overall, 1,291 lung cancers were observed among 28,546 male cohort members with a mean of 21 WLM (range 0-875) of cumulative exposure. For histology-specific analysis there were 391 SqCC, 249 ADC, 225 LCC, and 181 SmCC lung cancers. For all lung cancers combined, an increasing risk was observed with cumulative radon exposures measured in Working Levels Months (WLM). The strongest associations were observed for SqCC and SmCC. In the highest exposure category (&gt;60 Working Level Months) much stronger excess risks were observed for SqCC (RR=2.0, 95% CI=1.4-2.9) and SmCC (RR=2.1, 95% CI=1.3-3.5) than for ADC (RR=1.2, 95% CI=0.8-1.9) and LCC (RR=1.6, 95% CI=1.0-2.4), allowing for a 5-year lag of exposures. Conclusions: This study found higher relative risks for squamous and small cell carcinomas than for other histologic types and supports the limited evidence from other studies for histology-specific effects in radon induced lung cancer. Although limited by a lack of smoking data, the study has significant strengths including its quantitative exposure assessment, access to national tumor registry data, and large size.

Study of the Changes on Tree Shrew Bronchial Epithelium Induced by Xuanwei Bituminous Coal Dust

背景与目的肺癌在许多国家和地区已成为发病率和死亡率最高的恶性肿瘤，建立科学合适的肺癌动物模型，用以模拟出与人类肺癌的病因、发病机制、发展过程相似的动物模型是亟待解决的问题。通过宣威烟煤粉尘PM10（particulate matter with diameters of 10 μm or less, PM10）对树鼩支气管上皮的影响，探索建立宣威烟煤粉尘致肺癌模型的可行性。方法健康成年树鼩，切开颈部皮肤，充分暴露甲状软骨，于甲状软骨上方薄弱处，采用特制灌注针行穿刺的方法进行气管内试剂灌注。定期行X线检查，观察肺部影像学改变，处死动物行肺组织病理检查，观察灌注后支气管上皮改变情况。结果烟尘处理组树鼩灌注药物后1周内开始死亡，空白对照组、溶剂对照组树鼩灌注后至实验结束无异常死亡。定期处死树鼩行肺组织HE染色切片病理检查，空白对照组及溶剂对照组无明显病理改变，烟尘处理组树鼩肺组织可见支气管粘膜上皮过度增生-鳞状化生-不典型增生-早期浸润癌的病理变化过程。结论宣威烟煤粉尘可以导致树鼩支气管上皮出现支气管粘膜上皮过度增生-鳞状化生-不典型增生-早期浸润癌的病理变化，应用宣威烟煤粉尘PM10行气管内灌注可以诱发树鼩肺癌。可以建立肺癌模型。

Interleukin-6 Prevents the Initiation but Enhances the Progression of Lung Cancer.

Recent studies suggest that high expression of the proinflammatory cytokine IL6 is associated with poor survival of lung cancer patients. Accordingly, IL6 has been a target of great interest for lung cancer therapy. However, the role of IL6 in lung cancer has not been determined yet. Here, we demonstrate that IL6 plays opposite roles in the initiation and growth of lung cancer in a mouse model of lung cancer induced by the K-Ras oncogene. We find that compared with wild-type mice, IL6-deficient mice developed much more lung tumors after an activating mutant of K-Ras was induced in the lungs. However, lung tumors developed in IL6-deficient mice were significantly smaller. Notably, both the lung tumor-suppressing and -promoting functions of IL6 involve its ability in activating the transcription factor STAT3. IL6/STAT3 signaling suppressed lung cancer initiation through maintaining lung homeostasis, regulating lung macrophages, and activating cytotoxic CD8 T cells under K-Ras oncogenic stress, whereas it promoted lung cancer cell growth through inducing the cell proliferation regulator cyclin D1. These studies reveal a previously unexplored role of IL6/STAT3 signaling in maintaining lung homeostasis and suppressing lung cancer induction. These studies also significantly improve our understanding of lung cancer and provide a molecular basis for designing IL6/STAT3-targeted therapies for this deadliest human cancer.

Abstract 1541: Secreted serglycin in tumor microenvironment promotes tumor malignancies in a CD44-dependent manner

Abstract Tumor microenvironment (TME) plays an important role in cancer progression; however, the communication between TME and cancer cells remains largely unclear. CD44, a type I cell surface receptor functioning in cell-cell and cell-extracellular matrix interactions, has been implicated in tumor formation and progression. Using gain-of-function and loss-of-function approaches, we report in this study that serglycin (SRGN), a glycoprotein secreted from cancer-associated fibroblasts (CAFs) as well as aggressive cancer cells, works to promote the malignant behaviors of non-small cell lung cancer cells through its interaction with CD44. We showed that SRGN promotes cell transformation and tumor formation and metastasis using in vitro and in vivo tumorigenic assays. Furthermore, we showed that SRGN induced lung cancer cell stemness in a CD44-dependent manner. SRGN enhanced cancer cells sphere formation via Nanog induction, accompanied with increased drug resistance and resistance to anoikis. We also demonstrated that SRGN promotes cell migratory activity through promoting epithelial-mesenchymal transition (EMT) and enhancing adhesions turnover by upregulating vimentin expression and SRC activity via CD44/NF-KB/Claudin-1 axis. In support, Claudin-1 expression was tightly associated with SRGN expression in primary lung cancer tissues (p &amp;lt; 0.0001). In summary, we demonstrate that the crosstalk between tumor cells and TME promotes malignant phenotypes through the interaction of tumor-borne CD44 and CAF- or tumor-derived SRGN, suggesting that targeting CD44 or its ligands may represent an attractive strategy for development of cancer therapy. Citation Format: Jing-You Guo, Shiaw-Wei Tyan, Han-Shui Hsu, Fen-Yau Li, Jeou-Yuan Chen. Secreted serglycin in tumor microenvironment promotes tumor malignancies in a CD44-dependent manner. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1541. doi:10.1158/1538-7445.AM2015-1541

Abstract 2729: Chronic stress promotes lung cancer development via IGF-1R pathway

Abstract Lung cancer is a leading cause of cancer death worldwide. Although smoking is a main cause, approximately 25% of lung cancer cases are not attributable to tobacco use. Epidemiological studies strongly suggest that chronic stress influences cancer development and progression. Recent mechanistic studies showed that biological signaling pathways could contribute to such effects. But the underlying mechanisms for the association between chronic stress and lung cancer development are poorly understood. The purpose of this study is to investigate whether chronic stress can induce lung cancer development and, if so, what is the mechanism underlying the chronic stress-induced lung cancer development. We observed that stress hormone, norepinephrine (NE) increased cell viability in the absence of growth factors, foci formation, and colony formation in human bronchial epithelial cells and activated the type 1 insulin-like growth factor receptor (IGF-1R) pathway. We found that chronic stress resulted in high levels of NE in serum, activation of IGF-1R in lung tissue and promoted urethane-induced lung tumor formation in vivo. Moreover, inhibition of the IGF-1R pathway suppressed NE-induced transformed phenotypes in vitro. We further confirmed that chronic stress-induced lung tumor formation was greater in mice carrying lung-specific human IGF-1R transgene (Tg) than in wild type mice. Our results indicate that chronic stress may promote lung cancer development via the IGF-1R pathway, suggesting that IGF-1R is an effective target for the chemoprevention of stress-induced lung cancer. Citation Format: Hyun-Ji Jang, Hye-Jin Boo, Yujin Jung, Hye-Young Min, Ho-Young Lee. Chronic stress promotes lung cancer development via IGF-1R pathway. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2729. doi:10.1158/1538-7445.AM2015-2729

Abstract LB-265: Comparison of oleanane triterpenoids and dimethyl fumarate in lung cancer

Abstract Lung cancer accounts for the highest number of cancer-related deaths in the United States, highlighting the need for better therapies. Nrf2 is an important therapeutic target as activation of this pathway detoxifies harmful insults and reduces oxidative stress. However, the role of Nrf2 in cancer biology is controversial. Protection against oxidative stress and inflammation can confer a survival advantage to tumor cells, leading to a poor prognosis, and constitutive activation of Nrf2 has been detected in numerous tumors. In our study, we examined the role of two clinically relevant classes of Nrf2 activators, the synthetic triterpenoids (CDDO-Im and CDDO-Me) and dimethyl fumarate (DMF) in mouse macrophages (Raw 264.7) and in VC1 lung cancer cells. Although both triterpenoids and DMF activated Nrf2, CDDO-Im and CDDO-Me were more potent than DMF. Specifically, 25-50 nM CDDO-Im or CDDO-Me increased NQO1 and HO-1 expression 100-fold. Conversely, 10 μM of DMF was necessary to elicit the same effect. Additionally, 100 nM of CDDO-Im significantly (p&amp;lt;0.05) reduced ROS production induced by tert-butyl hydroperoxide by 69%, while 10 μM of DMF reduced ROS production by 44%. Moreover, nitric oxide production was significantly decreased by triterpenoids at nanomolar concentrations while DMF had a similar effect at micromolar concentrations (p&amp;lt;0.05). Using microarray analysis, we examined whether these Nrf2 activators target the same genes. Only 52 of 99 Nrf2 genes were targeted by all three compounds, and each drug targeted a unique subset of Nrf2 genes. Notably, CDDO-Im, CDDO-Me and DMF induced HO-1 expression by 9.1, 5.3 and 1.6 fold respectively. We then utilized Nrf2 knockout fibroblasts to confirm that induction of HO-1 expression was regulated via both Nrf2-dependent and Nrf2-independent pathways. To examine the effect of these Nrf2 activators in vivo, A/J mice were injected with vinyl carbamate to induce lung cancer. Beginning one week after initiation, mice were fed drugs in diet for 15 weeks. CDDO-Me was the most effective drug in this model; it reduced the average number and size of tumors by 32% (2.2 ± 0.3) and 76% (0.09 ± 0.01), respectively, compared to controls (3.2 ± 0.2 and 0.4 ± 0.04; p&amp;lt;0.05). Average tumor burden was also reduced by 83% (0.2 ± 0.03), compared to the controls (1.2 ± 0.1; p&amp;lt;0.05). Additionally, the percentage of high-grade tumors significantly decreased from 52% in the controls to 31% in the CDDO-Me group (p&amp;lt;0.05). Though less potent, CDDO-Im had similar effects as CDDO-Me. In contrast, when mice were fed DMF in diet, the average number of tumors increased by 29% (4.1 ± 0.4) compared to controls (3.2± 0.2; p&amp;lt;0.05). The percentage of high-grade tumors in mice fed DMF diet also increased to 63% vs. 52% in the controls (p&amp;lt;0.05). These data indicate that DMF increased the severity of lung carcinogenesis in these mice. Collectively, our study suggests that although CDDO-Im, CDDO-Me and DMF all activate Nrf2, they target distinct genes, resulting in different effects for the prevention of lung cancer. Citation Format: Ciric To, Darlene B. Royce, Charlotte R. Williams, Renee Risingsong, Michael B. Sporn, Karen T. Liby. Comparison of oleanane triterpenoids and dimethyl fumarate in lung cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-265. doi:10.1158/1538-7445.AM2015-LB-265

Abstract 413: Targeting IL-6 as a preventive and therapeutic strategy for K-ras mutant lung cancer

Abstract Worldwide, lung cancer (LC) leads in cancer mortality and cigarette smoking (CS) is its principal cause. Activating mutations of K-ras are one of the most common alterations in LC and are associated with CS exposure. However, several studies have shown that smokers with chronic obstructive pulmonary disease (COPD), an inflammatory disease of the lung, have a higher risk of developing LC when compared to smokers without COPD. These facts suggest a strong link between COPD-type inflammatory lung microenvironment and K-ras mutant lung cancer. Unfortunately, attempts to directly target K-ras have thus far failed, clearly stating the need for new approaches to bring clinical benefits to patients with this undrugabble profile. Using a conditional K-ras induced lung cancer mouse model (CC-LR) we showed that K-ras mutant lung tumors have intrinsic inflammatory characteristics, and a bacterial lysate-induced COPD-like airway inflammation promotes lung cancer in this model. This was associated with release of the cytokine IL-6 and activation of the IL-6-responsive transcription factor STAT3. We showed that genetic ablation of IL-6 in this model results in a significant tumor reduction indicating an essential role for IL-6/STAT3 pathway in lung cancer promotion and introducing IL-6 as a druggable target for K-ras mutant lung tumor. Therefore, we blocked IL-6 using a monoclonal anti-IL-6 immunotherapy in our K-ras mutant model. Six week old CC-LR mice were injected intraperitoneally with 20 mg/kg dose of an anti-IL-6 monoclonal IgG1 antibody twice a week for eight weeks, while been exposed to the aerosolized bacterial lysate once weekly for 8 weeks. Anti-IL-6 therapy not only inhibited intrinsic lung cancer development by ∼78%, but also inhibited the tumor promoting effect of the COPD-like airway inflammation. It also decreased the expression of P-STAT3, proliferation marker, Ki67, and pro-angiogenic factors: VEGF, MMP-9 and CD31 in lung tissue. qPCR analysis of lung tissues from anti-IL-6 treated mice showed a decrease in Arginase1, FIZZ1, FOXP3, and IL-17 expression, with increased expression of Th1 markers, IFNγ and TBx21. Flow cytometry analysis of total lung inflammatory cells in CC-LR mouse showed a significant increase in the population of tumor associated macrophages (TAMs) during tumor progression from age 6 to 14 weeks, and COPD-like inflammation induced an increase in myeloid derived suppressor cell (MDSCs) population. Interestingly, we found a significant decrease in TAMs and MDSCs population after anti-IL-6 treatment. Taken together, we conclude that IL-6 blockade not only has cell intrinsic effect in K-ras mutant tumors but also edit the lung microenvironment toward an anti-tumor phenotype. Therefore, we propose pharmacological targeting of IL-6 alone or in combination with conventional cytotoxic therapy, or other targeted therapies for prevention and treatment of lung cancer patients with K-ras mutation. Citation Format: Mauricio S. Caetano, Amber M. Cumpian, Lei Gong, Seon H. Chang, Huiyuan Zhang, Humam N. Kadara, Cinthya Sternberg, Carlos G. Ferreira, Stephanie S. Watowich, Seyed J. Moghaddam. Targeting IL-6 as a preventive and therapeutic strategy for K-ras mutant lung cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 413. doi:10.1158/1538-7445.AM2015-413

Single nucleotide polymorphisms in VTI1A gene contribute to the susceptibility of Chinese population to non-small cell lung cancer.

Genome-wide association studies (GWAS) have determined a new single nucleotide polymorphism (SNP) called VTI1A (rs7086803) that induces lung cancer susceptibility in nonsmoking women in Asia. This study aimed to evaluate the association between the VTI1A gene and the susceptibility of Chinese patients to lung cancer; it was also conducted to investigate the relationship between VTI1A SNP and adiponectin receptor 1 expression. A total of 887 subjects were enrolled in this study. VTI1A (rs7086803) genotypes were determined by genotyping. Overall survival (OS) was evaluated using Kaplan-Meier analysis with a log-rank test. Multivariate regression analysis results indicated that the AA genotype of VTI1A (rs7086803) polymorphism was associated with an increased risk of developing non-small cell lung carcinoma (NSCLC) compared with the GG genotype (AA vs. GG: odds ratio [OR] = 2.020; 95% confidence interval [95% CI], 1.033-3.949, p = 0.037). The AA genotype of VTI1A (rs7086803) in smokers predicted significantly shorter OS (median survival time [MST]: AA 9.8 months, AG 19.3 months, GG 12.2 months, p = 0.017). Adiponectin receptor 1 expression in tumor tissues with the AA genotype was significantly lower than that for other genotypes (mean rank: AA 18.55, AG 25, GG 45.76, p = 0.001). The presence of the allele A of VTI1A (rs7086803) may be the allele contributing to the risk of lung cancer susceptibility in Chinese population. Smoking lung cancer patients with the AA genotype of VTI1A gene (rs7086803) had a poor survival rate. Adiponectin receptor 1 expression may be correlated with the susceptibility of the allele A of VTI1A.