Adjuvant Therapy For Lung Cancer Research Articles

Unraveling the Ferroptosis-inducing Potential of Methanol Leaves Extract of Prosopis Juliflora Via Downregulation of SLC7A11 and GPX4 mRNA Expression in A549 Lung Cancer Cells.

Prosopis juliflora has been employed in many traditional treatments. As evidenced by our earlier research, Prosopis juliflora leaf methanol extract (PJME) has a promising future in the fight against lung cancer. It may also be used in conjunction with other treatments to effectively manage lung cancer. The main objective of this study was to explore the potential of PJME to inhibit lung cancer in A549 cells, along with its underlying mechanisms of action. The antiproliferative effects were determined using MTT and LDH tests. Apoptosis- inducing capacity was evaluated using the DAPI staining, caspase-3 test, cytochrome C assay, PARP cleavage, and qRT-PCR. To investigate the mechanism of action of PJME in lung cancer, the levels of ROS, MMP, GSH, MDA, and specific ferroptosis indicators were measured. The experimental data of the current study indicated that exposure of A549 cells to PJME reduced cell viability and increased cellular cytotoxicity. The apoptosis-inducing ability of PJME in A549 cells was validated by enhanced nuclear condensation, level of the caspase- 3, cytochrome C, and PARP release. In addition, qRT-PCR investigations verified that the administration of PJME led to a decrease in the expression of anti-apoptotic gene Bcl2 while enhancing the mRNA level of pro-apoptotic genes, such as Bax and caspase-3, in A549 cells. The study also found that PJME has the ability to activate ferroptosis pathways, as evidenced by elevated reactive oxygen species (ROS) generation, changes in the levels of antioxidant markers (MDA and GSH), and decreased expression of SLC7A11 and GPX4. The results of the present study clearly showed that PJME inhibited the proliferation of A549 cells and induced ferroptosis by reducing the expression of the important targets SLC7A11 and GPX4. Further research is necessary to fully understand the clinical efficacy of PJME before it can be investigated as supplemental or adjuvant therapy for lung cancer.

NUF2 Expression in Cancer Tissues and Lymph Nodes Suggests Post-Surgery Recurrence of Non-Small Cell Lung Cancer.

In non-small cell lung cancer (NSCLC) cases, detecting potential lymph node metastases is essential to determine the indications for sublobar resection or adjuvant therapy. NUF2 is a tumor-specific antigen that is highly expressed in lung cancer tissues. However, the significance of analyzing NUF2 expression in dissected lymph nodes has not yet been studied. Thus, we investigated the association between NUF2 expression in lung cancer tissues and dissected lymph nodes and early recurrence of NSCLC to determine its usefulness as a marker of lymph node micrometastasis. This retrospective study quantified NUF2 expression in the cancer tissues of 88 patients with NSCLC who underwent complete resection using real-time polymerase chain reaction and investigated its relationship with clinicopathological features and prognosis. We also quantified NUF2 RNA expression in mediastinal lymph nodes from 255 patients with pN0 NSCLC who underwent complete resection with lymph node dissection and analyzed its association with prognosis. NUF2 expression in primary tumors was correlated with lymph node metastasis and unfavorable outcomes in terms of poor recurrence-free and cancer-specific survival. In N0 NSCLC cases, high NUF2 expression in mediastinal lymph nodes indicated poor prognosis, especially in lymph node recurrence. NUF2 emerges as a promising marker for predicting lymph node metastatic recurrence, offering potential utility in guiding post-surgical adjuvant therapy for lung cancer or assisting in intraoperative decisions for sublobar resection.

In vitro anti-cancer activity of a polyherbal preparation, VEDICINALS®9, against A549 human lung adenocarcinoma cells

PurposeNon-small cell lung cancer (NSCLC) is among the leading causes of morbidity and mortality worldwide. Despite the availability of several treatment options, the five-year survival rate of NSCLC is extremely low (<20%). This underlines the necessity of more effective therapeutic alternatives. In this context, plant-derived extracts and bioactive molecules extracted from plants, known collectively as phytoceuticals, represent an extremely variegated source of bioactive compounds with potent anticancer potential. In the present study, we tested the in vitro anticancer activity of a polyherbal preparation, VEDICINALS®9, containing nine different bioactive principles extracted by medicinal plants. MethodsThe anticancer activity of VEDICINALS®9 was investigated by measuring its impact on A549 human NSCLC cell proliferation (MTT assay and trypan blue staining), migration (wound healing assay and transwell chamber assay) and by measuring the impact on the expression of cancer-related proteins (Human XL Oncology Protein Array). ResultsWe show that VEDICINALS®9 at a concentration of 0.2% v/v has potent anticancer effect, significantly inhibiting A549 cell proliferation and migration. Mechanistically, this was achieved by downregulating the expression of proteins involved in cancer cell proliferation (Axl, FGF basic, enolase 2, progranulin, survivin) and migration (Dkk-1, cathepsins B and D, BCL-x, amphiregulin, CapG, u-plasminogen activator). Furthermore, treatment with VEDICINALS®9 resulted in increased expression of the oncosuppressor protein p53 and of the angiogenesis inhibitor endostatin. ConclusionsTaken together, our results provide proof of principle of the potent anticancer activity of the polyherbal preparation VEDICINALS®9, highlighting its enormous potential as an alternative or adjuvant therapy for lung cancer.

Amifostine attenuates bleomycin-induced pulmonary fibrosis in mice through inhibition of the PI3K/Akt/mTOR signaling pathway

Amifostine is a normal cell protection agent, not only used in the adjuvant therapy of lung cancer, ovarian cancer, breast cancer, nasopharyngeal cancer, bone tumor, digestive tract tumor, blood system tumor and other cancers in order to reduce the toxicity of chemotherapy drugs, and recent studies have reported that the drug can also reduce lung tissue damage in patients with pulmonary fibrosis, but its mechanism of action is not yet fully understood. In this study, we explored the potential therapeutic effects and molecular mechanisms of AMI on bleomycin (BLM)-induced pulmonary fibrosis in mice. A mouse model of pulmonary fibrosis was established using BLM. We then assessed histopathological changes, inflammatory factors, oxidative indicators, apoptosis, epithelial-mesenchymal transition, extracellular matrix changes, and levels of phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling pathway-related proteins in the BLM-treated mice to determine the effect of AMI treatment on these factors. BLM-treated mice had substantial lung inflammation and abnormal extracellular matrix deposition. Overall, treatment with AMI significantly improved BLM-induced lung injury and pulmonary fibrosis. More specifically, AMI alleviated BLM-induced oxidative stress, inflammation, alveolar cell apoptosis, epithelial-mesenchymal transition, and extracellular matrix deposition by regulating the PI3K/Akt/mTOR signaling pathway. This finding that AMI can alleviate pulmonary fibrosis in a mouse model by inhibiting activation of the PI3K/Akt/mTOR signaling pathway lays a foundation for potential future clinical application of this agent in patients with pulmonary fibrosis.

Natural Compound Allicin Containing Thiosulfinate Moieties as Transmembrane Protein 16A (TMEM16A) Ion Channel Inhibitor for Food Adjuvant Therapy of Lung Cancer.

Cancer is one of the most serious malignant diseases, and chemotherapy is cancer's main clinical treatment method. However, chemotherapy inevitably produces drug resistance, and side effects accompany them. Adjuvant therapy is an effective way to enhance chemotherapeutic drug sensitivity and reduce side effects. This study found allicin, garlic's active ingredient, is an inhibitor of transmembrane protein 16A (TMEM16A), a novel drug target of lung adenocarcinoma. Allicin concentration-dependently inhibited TMEM16A currents with an IC50 of 24.35 ± 4.14 μM. Allicin thiosulfinate moieties bound with R535A/E624A/E633A residues of TMEM16A blocked the ion transport function and downregulated TMEM16A protein expression affecting the mitogen-activated protein kinase signal transduction. Then, allicin reduced the viability and migration of LA795 cells, and induced cell apoptosis. Moreover, multitarget combination administration results indicated that the therapeutic effect of 3.56 mg/kg allicin and 3 mg/kg cisplatin combined administration was superior to the superposition of the two drugs alone, demonstrating that the anticancer effects of allicin and cisplatin were synergistic. In addition, low-concentration combined administration also avoided the side effects of cisplatin in mice. Based on the good tumor suppressor effect and high biosafety of allicin and cisplatin combination in vivo, allicin can be used for food adjuvant therapy of cisplatin chemotherapy.

Nuciferine Inhibits TMEM16A in Dietary Adjuvant Therapy for Lung Cancer.

Lung cancer is a malignant tumor with the highest morbidity and mortality rates. Food therapy is a common adjuvant treatment for lung cancer due to its safety and painlessness. Developing new functional food and exploring novel drug targets is important for lung cancer adjuvant therapy. This study confirmed that the active ingredient nuciferine of the lotus leaf was a novel TMEM16A inhibitor by whole-cell patch clamp experiments and site-directed mutagenesis experiments. CCK8 assay, colony formation assay, wound healing assay, and Annexin-V assay were combined to prove that nuciferine inhibited the proliferation and migration of lung cancer cells and promoted cancer cell apoptosis by targeting TMEM16A. Moreover, the combination of nuciferine and cisplatin significantly enhanced the anti-cancer effect of cisplatin. In addition, the signal transduction pathway of nuciferine regulating LA795 cell proliferation, migration, and apoptosis was confirmed by western blot experiments. In vivo experiments showed that nuciferine was a safe and effective natural anti-cancer product for lung cancer. Tissue section pathological detection and pharmacokinetic experiments verified that intragastric administration of nuciferine significantly enhanced the cancer therapy effect of cisplatin and counteracted the toxicity of high concentrations of cisplatin. Therefore, nuciferine is an ideal functional food for adjuvant lung cancer treatment.

Practical demonstration of time bias with administration of adjuvant therapy in lung cancer

Purpose/BackgroundImmortal time bias (ITB) can hinder appropriate interpretations of studies administering adjuvant therapies. Given the increase in National Cancer Data Base (NCDB) analyses evaluating postoperative radiation therapy (PORT) as an adjuvant therapy, we sought to practically demonstrate the effects of ITB by performing a series of simulated NCDB analyses. MethodsA simulated NCDB analysis was performed to examine how the reported benefit of PORT in stage III non-small cell lung cancer (NSCLC) may change with adjustment for ITB utilizing sequential land mark analysis (SLMA) and time dependent Cox (TDC) modeling. ResultsOn the simulation analysis of 6440 NSCLC patients, we found that the omission of PORT without ITB adjustment was associated with an increased risk of death (HR 1.17, p < 0.0001). After performing a sequential LMA, the detrmient of omitting PORT continued to decrease until it was no longer significant at 8 months, HR 1.05 (p = 0.09). With the TDC model, although still significant, the relative benefit of PORT decreased, to a HR of 1.07 (p = 0.02). ConclusionsImmortal time bias can alter the results of survival analyses if not carefully accounted for. Adjusting for this bias is essential for accurate data interpretation and to better quantify the impact and effect size of adjuvant therapies such as PORT.

Plasma-activated medium as adjuvant therapy for lung cancer with malignant pleural effusion

This study compared effects of plasma-activated medium (PAM) with effects of conventional clinical thermal therapy on both lung cancer cells and benign cells for management of malignant pleural effusion (MPE). For MPE treatment, chemotherapy, photodynamic therapy, and thermal therapy are used but caused systemic side effects, patient photosensitivity, and edema, respectively. Recent studies show that plasma induces apoptosis in cancer cells with minor effects on normal cells and is cost-effective. However, the effects of plasma on MPE have not been investigated previously. This study applied a nonthermal atmospheric-pressure plasma jet to treat RPMI medium to produce PAM, carefully controlled the long-life reactive oxygen and nitrogen species concentration in PAM, and treated the cells. The influence of PAM treatment on the microenvironment of cells was also checked. The results indicated that PAM selectively inhibited CL1–5 and A549 cells, exerting minor effects on benign mesothelial and fibroblast cells. In contrast to selective lethal effects of PAM, thermal therapy inhibited both CL1–5 and benign mesothelial cells. This study also found that fibroblast growth factor 1 is not the factor explaining why PAM can selectively inhibit CL1–5 cells. These results indicate that PAM is potentially a less-harmful and cost-effective adjuvant therapy for MPE.

Cellular retinol binding protein 1 transfection reduces proliferation and AKT-related gene expression in H460 non-small lung cancer cells

In recent years, new treatments with novel action mechanisms have been explored for advanced non-small cell lung cancer (NSCLC). Retinoids promote cancer cell differentiation and death and their trafficking and action is mediated from specific cytoplasmic and nuclear receptors, respectively. The purpose of this study was to investigate the effect of Cellular retinol binding protein-1 (CRBP-1) transfection in H460 human NSCLC cell line, normally not expressing CRBP-1. H460 cells were transfected by using a vector pTargeT Mammalian expression system carrying the whole sequence of CRBP-1 gene. For proliferation and apoptosis studies, cells were treated with different concentrations of all-trans Retinoic Acid (atRA) and retinol. AKT-related gene expression was analyzed by using western blot and Signosis array and results analysed by one-way analysis of variance (ANOVA) or by t-student test. CRBP-1+ showed reduced proliferation and viability in basal condition and after atRA treatment when compared to empty-transfected H460 cells. Reduced proliferation in CRBP-1+ H460 cells associated to the down-regulation of pAKT/pERK/pEGFR-related genes. In particular, gene array documented the down-regulation of AKT and Stat-3-related genes, including M-Tor, Akt1, Akt2, Akt3, Foxo1, p27, Jun. Restoration of CRBP-1 expression in H460 cells reduced proliferation and viability in both basal condition and after atRA treatment, likely by down-regulating AKT-related gene level. Further studies are needed to better clarify how those CRBP-1-related intracellular pathways contribute to counteract NSCLC progression in order to suggest a potential tool to improve efficacy of retinoid anti lung cancer adjuvant therapy.

Renin-Angiotensin System in Lung Tumor and Microenvironment Interactions.

The mechanistic involvement of the renin-angiotensin system (RAS) reaches beyond cardiovascular physiopathology. Recent knowledge pinpoints a pleiotropic role for this system, particularly in the lung, and mainly through locally regulated alternative molecules and secondary pathways. Angiotensin peptides play a role in cell proliferation, immunoinflammatory response, hypoxia and angiogenesis, which are critical biological processes in lung cancer. This manuscript reviews the literature supporting a role for the renin-angiotensin system in the lung tumor microenvironment and discusses whether blockade of this pathway in clinical settings may serve as an adjuvant therapy in lung cancer.

EGCG regulates CTR1 expression through its pro-oxidative property in non-small-cell lung cancer cells.

Copper transporter 1 (CTR1)plays an important role in increasing cisplatin intake. Our previous studies showed that CTR1 expression was upregulated by (-)-epigallocatechin-3-gallate (EGCG), a green tea polyphenol, therefore enhanced cisplatin sensitivity in ovary cancer and non-small-cell lung cancer (NSCLC) cells. In the current study in the non-small-cell lung cancer cells, we uncovered a potential mechanism of EGCG-induced CTR1 through its pro-oxidative property. We found that EGCG increased reactive oxygen species (ROS) generation, while in the presence of ROS scavenger N-acetyl-cysteine (NAC), ROS production was eliminated. Changes of CTR1 expression were consistent with the ROS level. Simultaneously, EGCG downregulated ERK1/2 while upregulated lncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) through ROS to induce CTR1 expression. Besides, in a nude mouse xenografts model, EGCG treatment raised ROS level, expression of CTR1 and NEAT1 in tumor tissue. Also, ERK1/2 and p-ERK1/2 were suppressed as well. Taken together, these results suggested a novel mechanism that EGCG mediated ROS to regulate CTR1 expression through the ERK1/2/NEAT1 signaling pathway, which provided more possibilities for EGCG as a natural agent in adjuvant therapy of lung cancer.

Antrodia cinnamomea Inhibits Growth and Migration of Lung Cancer Cells through Regulating p53-Bcl2 and MMPs Pathways.

Antrodia cinnamomea has been shown to possess antitumor activity. This study investigated the effects and mechanisms of Antrodia cinnamomea extract (ACE) on growth and migration of human non-small cell lung cancer A549 cells. The effect of ACE on cell viability was determined by MTT assay and fluorescent live-cell imaging. The apoptotic effect of ACE was determined by cell cycle distribution using flow cytometry. A P53-mediated apoptosis pathway was identified by measuring protein expression of p53 and Bcl-2 with Western blotting. Additionally, mRNA expression of p53 and Bcl-2 and Bax was detected by qRT-PCR. The effect of ACE on cancer cell migration was confirmed by a wound-healing assay. Expression of MMP-2 and MMP-9 at the protein and gene levels was determined by western blot and qRT-PCR analysis. This study demonstrates the inhibitory effect of ACE on A549 cell proliferation in a dose-response manner with an [Formula: see text]. It was determined that ACE concentration at [Formula: see text] induced cell cycle arrest at S phase in A549 cells. The apoptosis-regulating protein p53 expression was enhanced and also associated with the downregulation of Bcl-2 in ACE treatment cells. The mRNA expression of p53 and Bcl-2 associated with Bxa was consistent with protein expression. The inhibition of migration of cancer cells treated with ACE was clearly evident. At the same time, suppression of expression of MMP-2 and MMP-9 at protein and mRNA levels was observed. The findings of this study highlight ACE as a potential agent of adjuvant therapy for lung cancer.

The 100 most cited articles on thoracic surgery management of lung cancer.

Lung cancer is the leading cause of cancer-related deaths worldwide. In 2019, 228,150 new lung cancer cases and 142,670 cancer deaths are projected to occur in the United States (1), and non-small cell lung cancer (NSCLC) accounts for nearly 85% of all diagnosed cases (1,2). As the US Preventative Services Task Force has released recommendations of computed tomography lung cancer screening for long-term smokers, the incidence of newly diagnosed lung cancer will have a marked increase (3). Over the past two decades, the therapies for lung cancer have evolved into a mature subspecialty, also being the culmination of a progressive research initiative and the continued innovation of interventional techniques. For operable NSCLC, the current guideline states that VATS lobectomy is the standard operation (4,5). In recent years, a great progress in the clinical treatment and basic research of adjuvant therapy for lung cancer has been obtained, such as chemotherapy, radiotherapy, target therapy, and immunotherapy (6-8). A large amount of literature is available to thoracic medicine specialists who perform thoracic surgery management of lung cancer. It is difficult to recognize articles of significance since the quality of the literature varies substantially and includes low impact studies and open access journals. An understanding of the available literature and the most heavily cited works will allow for a better understanding of the evidence base when discussing and providing these treatments. A bibliometric analysis is a quantitative method used to examine the knowledge structure and development of a research field and its publications. Among all the bibliometric methods, the citation analysis is the most common which focuses on citation number and number of citations per year (9,10). It evaluates the impact an article has had on a specific field of medicine by measuring the number of citations an article has received. Since 1971, the global output of academic research into the management of lung cancer has increased. There has been no specific quantitative analysis on the articles which have had the most significant impact on the treatment of lung cancer been performed. The aim of this study was to perform a citation analysis on the most cited articles in the thoracic surgery management for lung cancer and analyze each article individually, collecting the article type, year of publication, topic of interest, citation index, authorship, country of origin, institution, and level of evidence.

PO-015 Potentiating anti-neoplastic effect of cisplatin by a protein arginine methyltransferase 5 selective inhibitor in lung adenocarcinoma cells

IntroductionProtein arginine methyltransferase 5 (PRMT5) is an enzyme that is greatly implicated in diverse cellular processes, including transcriptional regulation, RNA metabolism, and cell-cycle regulation. It was found in previous studies to be highly expressed in cancers including lung adenocarcinoma, Hepatocellular Carcinoma (HCC), and melanoma; in amounts much more significant as compared to benign tissues; raising evidence that PRMT5 is involved in tumorigenesis. Recent studies have proven that inhibition of PRMT5 in HCC cells through the use of AMI-1, a water soluble selective protein arginine methyltransferase inhibitor significantly reduces the proliferation and migration of HCC cells. It was also found that β-catenin is a target of PRMT5, therefore inhibiting PRMT5 resulted in the silencing of β-catenin; as well as its downstream cell-cycle regulator cyclin D1. The aim of our study is to investigate the effect of PRMT5 inhibitor (AMI-1) on the proliferation, migration and survival of lung adenocarcinoma cells.Material and methodsWe compared the effect of AMI-1 on lung adenocarcinoma (A549 cell line) suppression with the standard chemotherapeutic agent, cisplatin, by measuring cell viability using MTT assay, PMRT5/β-catenin expression via Western Blotting, the extent of cell migration through wound healing assay, and survival of cancer cells by performing cell cycle progression and Annexin-V staining assays.Results and discussionsTreating the cells with a combination of 10 µM AMI-1 and IC50 of Cisplatin (23.4 µM) significantly decreased cell viability at 24 and 48 hours. Moreover, treatment with both drugs at 48 hours led to a reduction in cell migration measured by the migration rate. AMI-1 induced G2/M arrest in A549 cells at 24 hours. This effect was enhanced in the combined treatment. Furthermore, A549 cells were unable to recycle again as they arrested at G1 after 48 hours of combination treatment. There was a minor cell death induction after 48 hours of treatment with both drugs. Neither PRTM5 nor β-catenin protein levels were affected due to the treatment. However, 48 hours treatment with AMI-1 alone or in combination with Cisplatin reduced the methylation of PRTM5- downstream target, Histone 4.ConclusionInhibition of the intracellular enzyme protein arginine methyltransferase 5 by AMI-1 potentiates the anti-cancer effect to cisplatin in the lung adenocarcinoma, with a promising potential role as an adjuvant therapy in lung cancer. The?effect is likely mediated by methylation reduction of histone-4.

Synergistic Antitumor Effect of Oligogalacturonides and Cisplatin on Human Lung Cancer A549 Cells.

Cisplatin (DPP), a clinically potent antineoplastic agent, is limited by its severe adverse effects. The aim of this study was to investigate the effect of oligogalacturonides (OGA) and DDP on human lung cancer A549 cells. The combined use of OGA and DDP had a synergistic effect on the growth inhibition of A549 cells, changed the cell cycle distribution, and enhanced apoptotic response, especially in sequential combination treatment group of DDP 12 h + OGA 12 h. Western blot analyses showed that the combination treatment of OGA and DDP upregulated Bax, p53, and Caspase-3 and downregulated Bcl-2 proteins. More importantly, DDP-induced toxicity was attenuated by OGA and DDP combination treatment in normal HEK293 cells. Our data suggests that the combined use of OGA from natural sources and DDP could be an important new adjuvant therapy for lung cancer as well as offer important insights for reducing kidney toxicity of DDP and delaying the development of DDP resistance.

Combination of carboplatin and intermittent normobaric hyperoxia synergistically suppresses benzo[a]pyrene-induced lung cancer.

Background/AimsWe explored the effects of intermittent normobaric hyperoxia alone or combined with chemotherapy on the growth, general morphology, oxidative stress, and apoptosis of benzo[a]pyrene (B[a]P)-induced lung tumors in mice.MethodsFemale A/J mice were given a single dose of B[a]P and randomized into four groups: control, carboplatin (50 mg/kg intraperitoneally), hyperoxia (95% fraction of inspired oxygen), and carboplatin and hyperoxia. Normobaric hyperoxia (95%) was applied for 3 hours each day from weeks 21 to 28. Tumor load was determined as the average total tumor numbers and volumes. Several markers of oxidative stress and apoptosis were evaluated.ResultsIntermittent normobaric hyperoxia combined with chemotherapy reduced the tumor number by 59% and the load by 72% compared with the control B[a]P group. Intermittent normobaric hyperoxia, either alone or combined with chemotherapy, decreased the levels of superoxide dismutase and glutathione and increased the levels of catalase and 8-hydroxydeoxyguanosine. The Bax/Bcl-2 mRNA ratio, caspase 3 level, and number of transferase-mediated dUTP nick end-labeling positive cells increased following treatment with hyperoxia with or without chemotherapy.ConclusionsIntermittent normobaric hyperoxia was found to be tumoricidal and thus may serve as an adjuvant therapy for lung cancer. Oxidative stress and its effects on DNA are increased following exposure to hyperoxia and even more with chemotherapy, and this may lead to apoptosis of lung tumors.

Ethanol extract of Kilkyung-baeksan, a traditional herbal formula, induces G0/G1 cell cycle arrest in human lung cancer cell lines

BackgroundDespite current advances in diagnostics and medicines, the incidence of lung cancer is increasing and effective treatment is very challenging. Traditional herbal formulae as well as many herbal plant extracts have been recognized as attractive sources for novel multi-targeted therapy of cancer with minimal side effects. MethodsThe ethanol extract of Kilkyung-baeksan (EE-KKBS) and its component herbs were tested for their ability to inhibit cancer growth in several lung cancer cell lines. The effects of EE-KKBS and ethanol extract of Croton tiglium Linné seed (EE-CT) on cell cycle progression were measured by flow cytometric analysis using propidium iodide staining. Western blot analyses were performed to measure the expression profiles of proteins regulating cell cycle checkpoints. ResultsEE-KKBS inhibited the growth of lung cancer cells after 24–72hours treatment. Lung cancer cells treated with either EE-KKBS or EE-CT showed strong G0/G1 cell cycle arrest. The expressions of p21 and p27, two key regulators of G1 cell cycle checkpoint, were significantly upregulated upon treatment with EE-KKBS and EE-CT. ConclusionEE-KKBS exerted its cytostatic activity through regulating G1 cell cycle checkpoint in lung cancer cells, and this activity is mainly mediated by one of its component herbs, seeds of Croton tiglium. Collectively, our data suggest that EE-KKBS could be a novel candidate for adjuvant therapy for lung cancer.

Abstract 1726: CRM1 is overexpressed in lung tumorigenesis and represents an adjuvant target for lung cancer treatment

Abstract In spite of extensive investigations, the molecular mechanisms of lung tumorigenesis have not been completely understood, and the effective therapy for lung cancer is in great demand. Studies have shown that chromosome region maintenance 1 (CRM1), a nuclear export receptor for various cancer-associated ‘cargo’ proteins, overexpressed in several human cancers. The objectives of the present study are to evaluate the involvement of CRM1 in lung carcinogenesis and lung cancer treatment. First, we have analyzed the importance of CRM1 overexpression in lung cancer development. We showed that CRM1 was overexpressed in lung tumor tissues from lung cancer patients and lung adenocarcinoma in mice induced by a tobacco carcinogen, as well as lung cancer cell lines. The increased CRM1 expression levels in these lung cancer tissues and cells were associated with an increased phosphorylation level at threonine residue 55 of the p53 protein. Furthermore, CRM1 overexpression in lung cancer cells seemed to be p53-dependent. Stable overexpression of CRM1 in BEAS-2B cells led to malignant cellular transformation and p53 cytoplasmic localization. Moreover, as compared to A549 cells, cancer-related genes significantly altered in A549 cells with stable CRM1 knockdown. Second, we have evaluated targeting CRM1 as an adjuvant therapy for lung cancer treatment using both in vitro and in vivo models. We found that CRM1-siRNA could inhibit A549 cell growth and A549 cells with stable CRM1 knockdown showed more pronounced cytotoxic effects to cisplatin than A549 cells. In addition, A549 cells treated with cisplatin and a low non-toxic dose of leptomycin B (a CRM1 inhibitor) had a remarkably enhanced cytotoxicity compared to cisplatin. This increased therapeutic effect from leptomycin B and cisplatin was further validated using an in vivo xenograft mouse model. The findings of this study reveal the significance of CRM1 in lung carcinogenesis and lung cancer adjuvant therapy. Citation Format: Weimin Gao, Chuanwen Lu, Lixia Chen, Phouthone Keohavong. CRM1 is overexpressed in lung tumorigenesis and represents an adjuvant target for lung cancer treatment. [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 1726. doi:10.1158/1538-7445.AM2015-1726

Overexpression of CRM1: A Characteristic Feature in a Transformed Phenotype of Lung Carcinogenesis and a Molecular Target for Lung Cancer Adjuvant Therapy

Our previous study showed that chromosome region maintenance 1 (CRM1), a nuclear export receptor for various cancer-associated "cargo" proteins, was important in regulating lung carcinogenesis in response to a tobacco carcinogen, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). The objectives of this study are to comprehensively evaluate the significance of CRM1 in lung cancer development and investigate the therapeutic potential of targeting CRM1 for lung cancer treatment using both in vitro and in vivo models. We showed that CRM1 was overexpressed not only in lung tumor tissues from both lung cancer patients and mice treated with NNK but also in NNK-transformed BEAS-2B human bronchial epithelial cells. Furthermore, stable overexpression of CRM1 in BEAS-2B cells by plasmid vector transfection led to malignant cellular transformation. Moreover, a decreased CRM1 expression level in A549 cells by short hairpin siRNA transfection led to a decreased tumorigenic activity both in vitro and in nude mice, suggesting the potential to target CRM1 for lung cancer treatment. Indeed, we showed that the cytotoxic effects of cisplatin on A549 cells with CRM1 down-regulated by short hairpin siRNA were significantly increased, compared with A549 cells, and the cytotoxic effects of cisplatin became further enhanced when the drug was used in combination with leptomycin B, a CRM1 inhibitor, in both in vitro and in vivo models. Cancer target genes were significantly involved in these processes. These data suggest that CRM1 plays an important role in lung carcinogenesis and provides a novel target for lung cancer adjuvant therapy.

Inhalation Adjuvant Therapy for Lung Cancer

Lung cancer is the leading cause of new cancer cases and also is the number one cause of cancer death in both male and females in the United States and the world. Lung cancer is histologically separated into either small-cell (SCLC) or nonsmall-cell lung cancer (NSCLC). NSCLC is much more common, and can occur in the periphery (adenocarcinomas) or central airways (squamous cell carcinomas). The literature pertaining to lung cancer adjuvant therapy and inhalation lung cancer chemoprevention was reviewed. It is argued that inhalation of chemotherapy as an adjuvant in Stage II NSCC and inhalation of chemopreventive agents in Stage I adenocarcinomas are direct paths to improve lung cancer therapy as well as demonstrate the utility of inhalation therapy. If successful, inhalation delivery may be extended to the treatment of other types of lung cancer.