Adjuvant Therapy in Non–Small Cell Lung Cancer: Future Treatment Prospects and Paradigms

Monoclonal Antibodies in Oncology: A Decade of Novel Options

Several decades of research and clinical trials have conclusively provided proof of concept on the usefulness of monoclonal antibodies in the armamentarium against cancer. There are numerous mAbs approved for both, the treatment of solid tumors as well as hematological malignancies. These have ranked in the top ten best-selling drugs in recent years and one such mAb, pembrolizumab, is slated to be the highest revenue-generating drug by 2024. A large proportion of the mAbs in oncology have been approved by regulatory agencies in just the past decade and many professionals working in the field have been unable to keep abreast with the latest mAbs available and their mechanism of action. In this review, we aim to provide a systematic compilation of the various mAbs in oncology, approved by the US FDA in the past decade. It also elaborates on the mechanism of action of the newly approved mAbs to provide an overall update of the same. For this purpose, we have referred to the Drugs at FDA and relevant articles from PubMed from the year 2010 to date.

circSNX6 (hsa_circ_0031608) enhances drug resistance of non-small cell lung cancer (NSCLC) via miR-137

circRNAs have been suggested to modulate NSCLC tumorigenesis and drug resistance. Whether circSNX6 affects NSCLC remains unclear. In this study, we aim to investigate the role of circSNX6 in drug resistance of NSCLC exposed to cisplatin. RT-qPCR method was used to investigate expression levels of circSNX6, miR-137 and CXCL12. MTT, cell colony formation and TUNEL assays were utilized to assess cell viability, proliferation, apoptosis, respectively. Xenograft assay was conducted to examinein vivotumor growth. circSNX6 overexpression caused enhanced cell viability and proliferation of H1299 and Calu-1, while it inhibited apoptosis under cisplatin treatment. miR-137 inhibitor greatly rescued cell viability, proliferation and apoptosis of circSNX6 knockdown H1299 cells. miR-137 mimic increased ROS generation, as well as reduced GSH and SOD levels, whereas miR-137 inhibitor exerted opposing effect. circSNX6 knockdown also enhanced ROS generation, as well as decreased GSH and SOD levels. CXCL12 partially restored miR-137 mimic-modulated cell viability, proliferation and apoptosis. Herein, our group proposes circSNX6 as key regulator for drug resistance of NSCLC. The findings provide solid groundings for understanding of NSCLC pathogenesis and development of therapeutics.

RBBP4 Enhances Platinum Chemo Resistance in Lung Adenocarcinoma

Background

The majority of lung cancers are adenocarcinomas, with the proportion being 40%. The patients are mostly diagnosed in the middle and late stages with metastasis and easy recurrence, which poses great challenge to the treatment and prognosis. Platinum-based chemotherapy is a primary treatment for adenocarcinoma, which frequently causes drug resistance. As a result, it is important to uncover the mechanisms of the chemoresponse of adenocarcinoma to platinum-based chemotherapy.

Methods

The genes from the dataset GSE7880 were gathered into gene modules with the assistance of weighted gene coexpression network analysis (WGCNA), the gene trait significance absolute value (|GS|), and gene module memberships (MM). The genes from hub gene modules were calculated with a protein-protein interaction (PPI) network analysis in order to obtain a screening map of hub genes. The hub genes with both a high |GS| and MM and a high degree were selected. Furthermore, genes in the hub gene modules also went through a Gene Ontology (GO) functional enrichment analysis.

Results

11 hub genes in four hub gene modules (LY86, ACTR2, CDK2, CKAP4, KPNB1, RBBP4, SMAD4, MYL6, RPS27, TSPAN2, and VAMP2) were chosen as the significant hub genes. Through the GO function enrichment analysis, it was indicated that four modules were abundant in immune system functions (floralwhite), amino acid biosynthetic process (lightpink4), cell chemotaxis (navajowhite2), and targeting protein (paleturquoise). Four hub genes with the highest |GS| were verified by prognostic analysis.

Development and validation of nomograms for predicting survival probability of patients with advanced adenocarcinoma in different EGFR mutation status

INTRODUCTION

Molecular markers are important variables in the selection of treatment for cancer patients and highly associated with their survival. Therefore, a nomogram that can predict survival probability by incorporating epidermal growth factor receptor mutation status and treatments for patients with advanced adenocarcinoma would be highly valuable. The aim of the study is to develop and validate a novel nomogram, incorporating epidermal growth factor receptor mutation status and treatments, for predicting 1-year and 2-year survival probability of patients with advanced adenocarcinoma.

MATERIAL AND METHODS

Data on 13,043 patients between June 1, 2011, and December 31, 2014 were collected. Seventy percent of them were randomly assigned to the training cohort for nomogram development, and the remaining 30% assigned to the validation cohort. The most important factors for constructing the nomogram were identified using multivariable Cox regression analysis. The discriminative ability and calibration of the nomograms were tested using C-statistics, calibration plots, and Kaplan-Meier curves.

RESULTS

In the training cohort, 1-year and 2-year OS were 52.8% and 28.5% in EGFR(-) patients, and 73.9% and 44.1% in EGFR(+) patients, respectively. In EGFR(+) group, factors selected were age, gender, congestive heart failure, renal disease, number of lymph node examined, tumor stage, surgical intervention, radiotherapy, first-line chemotherapy, ECOG performance status, malignant pleural effusion, and smoking. In EGFR(-) group, factors selected were age, gender, myocardial infarction, cerebrovascular disease, chronic pulmonary disease, number of lymph node examined, tumor stage, surgical intervention, radiotherapy, ECOG performance status, malignant pleural effusion, and a history of smoking. Two nomograms show good accuracy in predicting OS, with a concordance index of 0.83 in EGFR(+) and of 0.88 in EGFR(-).

CONCLUSIONS

The survival prediction models can be used to make individualized predictions with different EGFR mutation status and a useful tool for selecting regimens for treating advanced adenocarcinoma.

Long noncoding RNA Sox2 overlapping transcript (SOX2OT) promotes non-small-cell lung cancer migration and invasion via sponging microRNA 132 (miR-132)

Background

Long noncoding RNA (lncRNA) Sox2 overlapping transcript (SOX2OT) has been reported to be upregulated in various types of cancers, including non-small-cell lung cancer (NSCLC). However, the biological role and underlying mechanism of SOX2OT activity in NSCLC remain largely unknown. This study aims to investigate the function and possible molecular mechanisms of SOX2OT in NSCLC.

Materials and methods

Quantitative real-time polymerase chain reaction was used to detect SOX2OT expression, and cellular proliferation, migration, and invasion were measured using cell counting kit-8, wound healing, and Transwell invasion assays, respectively. Western blotting was used to determine protein expression. Starbase 2.0 and luciferase reporter assay were utilized to identify the molecular target of SOX2OT.

Results

Here, we discovered that SOX2OT was markedly upregulated in NSCLC tissues and cell lines. Knockdown of SOX2OT inhibited the proliferation, migration, invasion, and epithelial–mesenchymal transition (EMT) process in NSCLC cells. Moreover, we explored the regulatory mechanism of SOX2OT and found that SOX2OT directly bound microRNA 132 (miR-132) in NSCLC cells. Importantly, miR-132 inhibition partially reversed the SOX2OT knockdown-mediated inhibitory effect on cell proliferation, migration, invasion, and EMT process. We also found that SOX2OT could regulate zinc finger E-box-binding homeobox 2 (a target of miR-132) expression, which played crucial roles in tumor cell proliferation and invasion.

Conclusion

These findings indicated that SOX2OT was a noncoding oncogene that exerted important regulatory functions in NSCLC via sponging miR-132 and might represent a novel strategy for overcoming this disease.

The molecular and clinical verification of therapeutic resistance via the p38 MAPK-Hsp27 axis in lung cancer

Treatment failure followed by relapse and metastasis in patients with non-small cell lung cancer is often the result of acquired resistance to cisplatin-based chemotherapy. A cancer stem cell (CSC)-mediated anti-apoptotic phenomenon is responsible for the development of drug resistance. The underlying molecular mechanism related to cisplatin resistance is still controversial, and a new strategy is needed to counteract cisplatin resistance. We used a nonadhesive culture system to generate drug-resistant spheres (DRSPs) derived from cisplatin-resistant H23 lung cancer cells. The expressions of drug-resistance genes, properties of CSCs, and markers of anti-apoptotic proteins were compared between control cells and DRSPs. DRSPs exhibited upregulation of cisplatin resistance-related genes. Gradual morphological alterations showing epithelial-to-mesenchymal transition phenomenon and increased invasion and migration abilities were seen during induction of DRSPs. Compared with control cells, DRSPs displayed increased CSC and anti-apoptotic properties, greater resistance to cisplatin, and overexpression of p-Hsp27 via activation of p38 MAPK signaling. Knockdown of Hsp27 or p38 decreased cisplatin resistance and increased apoptosis in DRSPs. Clinical studies confirmed that the expression of p-Hsp27 was closely associated with prognosis. Overexpression of p-Hsp27 was usually detected in advanced-stage patients with lung cancer and indicated short survival.

MALAT1/miR-101-3p/MCL1 axis mediates cisplatin resistance in lung cancer

In this study, we investigated the mechanism by which lncRNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) mediates cisplatin resistance in lung cancer. Lung cancer patients with high MALAT1 levels were associated with cisplatin resistance and low overall survival. Moreover, cisplatin-resistant A549/DDP cells showed higher MALAT1 expression than cisplatin-sensitive lung cancer cells (A549, H460, H1299 and SPC-A1). Dual luciferase reporter and RNA immunoprecipitation assays showed direct binding of miR-101-3p to MALAT1. MALAT1 knockdown in lung cancer cells resulted in miR-101-3p upregulation and increased cisplatin sensitivity. In addition, miR-101-3p decreased myeloid cell leukemia 1 (MCL1) expression by binding to the 3’-untranslated region (3’-UTR) of its mRNA. These results demonstrate that MALAT1/miR-101-3p/MCL1 signaling underlies cisplatin resistance in lung cancer.

Development of an inhalable, stimuli-responsive particulate system for delivery to deep lung tissue

Lung cancer, the deadliest solid tumor among all types of cancer, remains difficult to treat. This is a result of unavoidable exposure to carcinogens, poor diagnosis, the lack of targeted drug delivery platforms and limitations associated with delivery of drug to deep lung tissues. Development of a non-invasive, patient-convenient formula for the targeted delivery of chemotherapeutics to cancer in deep lung tissue is the aim of this study. The formulation consisted of inhalable polyvinylpyrrolidone (PVP)/maltodextrin (MD)-based microparticles (MPs) encapsulating chitosan (CS) nanoparticles (NPs) loaded with either drug only or drug and magnetic nanoparticles (MNPs). Drug release from CS NPs was enhanced with the aid of MNPs by a factor of 1.7 in response to external magnetic field. Preferential toxicity by CS NPs was shown towards tumor cells (A549) in comparison to cultured fibroblasts (L929). The prepared spray freeze dried (SFD) powders for CS NPs and CS MNPs were of the same size at ∼6μm. They had a fine particle fraction (FPF≤5.2μm) of 40-42% w/w and mass median aerodynamic diameter (MMAD) of 5-6μm as determined by the Next Generation Impactor (NGI). SFD-MPs of CS MNPs possess higher MMAD due to the high density associated with encapsulated MNPs. The developed formulation demonstrates several capabilities including tissue targeting, controlled drug release, and the possible imaging and diagnostic values (due to its MNPs content) and therefore represents an improved therapeutic platform for drug delivery to cancer in deep lung tissue.

Cost-Utility of a Prognostic Test Guiding Adjuvant Chemotherapy Decisions in Early-Stage Non-Small Cell Lung Cancer

BACKGROUND

A prognostic test was developed to guide adjuvant chemotherapy (ACT) decisions in early-stage non-small cell lung cancer (NSCLC) adenocarcinomas. The objective of this study was to compare the cost-utility of the prognostic test to the current standard of care (SoC) in patients with early-stage NSCLC.

MATERIALS AND METHODS

Lifetime costs (2014 U.S. dollars) and effectiveness (quality-adjusted life-years [QALYs]) of ACT treatment decisions were examined using a Markov microsimulation model from a U.S. third-party payer perspective. Cancer stage distribution and probability of receiving ACT with the SoC were based on data from an academic cancer center. The probability of receiving ACT with the prognostic test was estimated from a physician survey. Risk classification was based on the 5-year predicted NSCLC-related mortality. Treatment benefit with ACT was based on the prognostic score. Discounting at a 3% annual rate was applied to costs and QALYs. Deterministic one-way and probabilistic sensitivity analyses examined parameter uncertainty.

RESULTS

Lifetime costs and effectiveness were $137,403 and 5.45 QALYs with the prognostic test and $127,359 and 5.17 QALYs with the SoC. The resulting incremental cost-effectiveness ratio for the prognostic test versus the SoC was $35,867/QALY gained. One-way sensitivity analyses indicated the model was most sensitive to the utility of patients without recurrence after ACT and the ACT treatment benefit. Probabilistic sensitivity analysis indicated the prognostic test was cost-effective in 65.5% of simulations at a willingness to pay of $50,000/QALY.

CONCLUSION

The study suggests using a prognostic test to guide ACT decisions in early-stage NSCLC is potentially cost-effective compared with using the SoC based on globally accepted willingness-to-pay thresholds.

IMPLICATIONS FOR PRACTICE

Providing prognostic information to decision makers may help some patients with high-risk early stage non-small cell lung cancer receive appropriate adjuvant chemotherapy while avoiding the associated toxicities and costs in patients with low-risk disease. This study used an economic model to assess the effectiveness and costs associated with using a prognostic test to guide adjuvant chemotherapy decisions compared with the current standard of care in patients with non-small cell lung cancer. When compared with current standard care, the prognostic test was potentially cost effective at commonly accepted thresholds in the U.S. This study can be used to help inform decision makers who are considering using prognostic tests.

Adjuvant chemotherapy after resection of N1 non-small cell lung cancer: differential impact of new evidence on physician and patient decisions

BACKGROUND

Adjuvant cisplatin-based chemotherapy (ACT) after resection of stages II-IIIA non-small cell lung cancer (NSCLC) modestly increased survival in several clinical trials. This study evaluated the subsequent impact of those trials on ACT use in clinical practice.

METHODS

Patients who underwent lobectomy or more extensive lung resection without induction chemotherapy for pathologically confirmed N1 positive NSCLC between 2000 and 2012 were reviewed. Referrals to medical oncology, oncologist recommendations for ACT, and initiation of ACT were evaluated. Because major trials supporting ACT were published in 2004 and 2005, analysis was stratified into two eras: 2000-2005 and 2006-2012.

RESULTS

During the study period, 272 patients met inclusion criteria (110 in the 2000-2005 cohort, 162 in the 2006-2012 cohort). Referrals to medical oncology increased from 74.5% (n=82) in the 2000-2005 cohort to 90.1% (n=146) in the 2006-2012 cohort (P=0.002). Due to lack of referral or missed appointments, 35.5% (n=39) of the 2000-2005 patients and 17.9% (n=32) of the 2006-2012 patients did not have a documented conversation with an oncologist regarding ACT. The proportion of patients recommended for ACT increased from 61% (n=50) to 81.5% (n=119) between the eras (P<0.001). Of patients recommended for chemotherapy, 14% (7/50) in 2000-2005 and 13.4% (16/119) in 2006-2012 declined ACT (P=0.666).

CONCLUSIONS

Publication of supporting evidence increased recommendations for ACT but did not change the percentage of patients who ultimately agreed to receive ACT. Additional research is needed to better understand patient decision-making in this situation.

Development and validation of a nomogram for predicting survival in patients with resected non-small-cell lung cancer

PURPOSE

A nomogram is a useful and convenient tool for individualized cancer prognoses. We sought to develop a clinical nomogram for predicting survival of patients with resected non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

On the basis of data from a multi-institutional registry of 6,111 patients with resected NSCLC in China, we identified and integrated significant prognostic factors for survival to build a nomogram. The model was subjected to bootstrap internal validation and to external validation with a separate cohort of 2,148 patients from the International Association for the Study of Lung Cancer (IASLC) database. The predictive accuracy and discriminative ability were measured by concordance index (C-index) and risk group stratification.

RESULTS

A total of 5,261 patients were included for analysis. Six independent prognostic factors were identified and entered into the nomogram. The calibration curves for probability of 1-, 3-, and 5-year overall survival (OS) showed optimal agreement between nomogram prediction and actual observation. The C-index of the nomogram was higher than that of the seventh edition American Joint Committee on Cancer TNM staging system for predicting OS (primary cohort, 0.71 v 0.68, respectively; P < .01; IASLC cohort, 0.67 v 0.64, respectively; P = .06). The stratification into different risk groups allowed significant distinction between survival curves within respective TNM categories.

CONCLUSION

We established and validated a novel nomogram that can provide individual prediction of OS for patients with resected NSCLC. This practical prognostic model may help clinicians in decision making and design of clinical studies.

Fisetin induces apoptosis in human nonsmall lung cancer cells via a mitochondria-mediated pathway

The present study investigated the apoptotic effects of fisetin, a phenolic compound, against the human nonsmall cell lung cancer cell line, NCI-H460. Fisetin showed dose-dependent cytotoxic activity against NCI-H460 cells, with 50% inhibition of cell viability occurring at a concentration of 75 μg/mL. Fisetin induced both the production of intracellular reactive oxygen species and apoptosis, as evidenced by apoptotic body formation, DNA fragmentation, an increase in the number of sub-G1 phase cells, and mitochondrial membrane depolarization. Moreover, fisetin significantly modulated the expression of apoptosis-associated proteins, resulting in reduced expression of B cell lymphoma-2, increased expression of Bcl-2-associated X protein, and activation of caspase-9 and caspase-3. In addition, pretreatment with a caspase inhibitor blocked fisetin-induced cell death.

Decreased ERCC1 Expression After Platinum-Based Neoadjuvant Chemotherapy in non-Small Cell Lung Cancer

We have already demonstrated in a small cohort of 17 non-small cell lung cancer patients that ERCC1 (excision repair cross-complementation group 1) protein expression decreased after platinum-based treatment, however, certain clinicopathological parameters, such as histologic subtypes, ERCC1 expression scores, chemotherapeutic combinations, response rate, gender and smoking history were not analyzed. The aim of our present study was to extend the studied cohort and analyze those parameters. ERCC1 protein expression was examined in 46 patients treated with neoadjuvant chemotherapy. 46 bronchoscopic biopsy samples (27 squamous cell carcinomas /SCC/ and 19 adenocarcinomas /ADC/) together with their corresponding surgical biopsies were studied. ERCC1 immunohistochemistry was performed on formalin-fixed, paraffin-embedded tissues. Staining scores were calculated by multiplying the percentage of positive tumor cells (0-100) by the staining intensity (0-3). 24/27 bronchoscopic SCC tissues expressed ERCC1. Thirteen of these cases became negative after neoadjuvant therapy and the expression differences between pre- and postchemotherapy samples were highly significant (p < 0.001). 11/19 bronchoscopic ADC tissues expressed ERCC1. Six of these cases became negative after neoadjuvant therapy and the expression differences were significant (p < 0.010). There was no newly expressed ERCC1 postoperatively. Comparison of staining score changes revealed more pronounced decrease in SCC (p = 0.032). We observed no correlation between initial ERCC1 level or ERCC1 decrease and overall survival, but we demonstrated correlations between decrease in ERCC1 expression and histologic subtypes of tumors and gender. We could confirm our previous data in a larger cohort that platinum-based chemotherapy affects the ERCC1 expression probably referring to an induction of tumor cell selection.

Transferrin-modified nanostructured lipid carriers as multifunctional nanomedicine for codelivery of DNA and doxorubicin

BACKGROUND

Nanostructured lipid carriers (NLC), composed of solid and liquid lipids, and surfactants are potentially good colloidal drug carriers. The aim of this study was to develop surface-modified NLC as multifunctional nanomedicine for codelivery of enhanced green fluorescence protein plasmid (pEGFP) and doxorubicin (DOX).

METHODS

TWO DIFFERENT NANOCARRIERS: pEGFP- and DOX-loaded NLC, and solid lipid nanoparticles (SLN) were prepared. Transferrin-containing ligands were used for the surface coating of the vectors. Their average size, zeta potential, and drug encapsulation capacity were evaluated. In vitro transfection efficiency of the modified vectors was evaluated in human alveolar adenocarcinoma cell line (A549 cells), and in vivo transfection efficiency of the modified vectors was evaluated in a mouse bearing A549 cells model.

RESULTS

Transferrin-modified DOX and pEGFP coencapsulated NLC (T-NLC) has a particle size of 198 nm and a +19 mV surface charge. The in vitro cell viabilities of the T-NLC formulations were over 80% compared with the control. T-NLC displayed remarkably greater gene transfection efficiency and enhanced antitumor activity than DOX- and pEGFP-coencapsulated SLN in vivo.

CONCLUSION

The results demonstrate that T-NLC noticeably enhanced antitumor activity through the combination of gene therapy with chemotherapy. Also coating of active transferrin improved the lung cancer cell-targeting of the carriers. In summary, the novel gene and drug delivery system offers a promising strategy for the treatment of lung cancer.

TREM-1 is induced in tumor associated macrophages by cyclo-oxygenase pathway in human non-small cell lung cancer

It is increasingly recognized that the tumor microenvironment plays a critical role in the initiation and progression of lung cancer. In particular interaction of cancer cells, macrophages, and inflammatory response in the tumor microenvironment has been shown to facilitate cancer cell invasion and metastasis. The specific molecular pathways in macrophages that immunoedit tumor growth are not well defined. Triggering receptor expressed on myeloid cells 1 (TREM-1) is a member of the super immunoglobulin family expressed on a select group of myeloid cells mainly monocyte/macrophages. Recent studies suggest that expression of TREM-1 in tumors may predict cancer aggressiveness and disease outcomes in liver and lung cancer however the mechanism of TREM-1 expression in the setting of cancer is not defined. In this study we demonstrate that tumor tissue from patients with non-small cell lung cancer show an increased expression of TREM-1 and PGE₂. Immunohistochemistry and immunofluorescence confirmed that the expression of TREM-1 was selectively seen in CD68 positive macrophages. By employing an in vitro model we confirmed that expression of TREM-1 is increased in macrophages that are co-cultured with human lung cancer cells. Studies with COX-2 inhibitors and siCOX-2 showed that expression of TREM-1 in macrophages in tumor microenvironment is dependent on COX-2 signaling. These studies for the first time define a link between tumor COX-2 induction, PGE₂ production and expression of TREM-1 in macrophages in tumor microenvironment and suggest that TREM-1 might be a novel target for tumor immunomodulation.

Effects of postoperative epidural analgesia on recurrence-free and overall survival in patients with nonsmall cell lung cancer

STUDY OBJECTIVE

To determine whether postoperative epidural analgesia is associated with better recurrence-free survival and overall survival after lung cancer surgery.

DESIGN

Retrospective study.

SETTING

Academic hospital.

MEASUREMENTS

Data of patients with stage 1, stage 2, and stage 3 nonsmall cell lung cancer, who underwent tumor resection surgery, were studied. Patient data were grouped into three different postoperative pain management interventions: intravenous patient-controlled analgesia, patient-controlled epidural analgesia, and their combination. Univariate and multicovariate Cox proportional hazards models were applied to assess the effects of covariates of interest on overall survival and recurrence-free survival.

MAIN RESULTS

The type of postoperative analgesia used for patients who underwent surgery for nonsmall cell lung cancer did not affect recurrence-free survival or overall survival. However, certain variables, including age ≥ 65 years, male gender, body mass index ≥ 25 kg/m(2), ASA physical status 4, and the need for preoperative blood transfusions, pneumonectomy, and postoperative radiation, were associated with decreased recurrence-free survival and overall survival.

CONCLUSIONS

The type of postoperative analgesia used after surgery for nonsmall cell lung cancer is not associated with better 2-year or 5-year recurrence-free survival or overall survival rates.

Vessel co-option in primary human tumors and metastases: an obstacle to effective anti-angiogenic treatment?

Angiogenesis has been regarded as essential for tumor growth and progression. Studies of many human tumors, however, suggest that their microcirculation may be provided by nonsprouting vessels and that a variety of tumors can grow and metastasize without angiogenesis. Vessel co-option, where tumor cells migrate along the preexisting vessels of the host organ, is regarded as an alternative tumor blood supply. Vessel co-option may occur in many malignancies, but so far mostly reported in highly vascularized tissues such as brain, lung, and liver. In primary and metastatic lung cancer and liver metastasis from different primary origins, as much as 10–30% of the tumors are reported to use this alternative blood supply. In addition, vessel co-option is introduced as a potential explanation of antiangiogenic drug resistance, although the impact of vessel co-option in this clinical setting is still to be further explored. In this review we discuss tumor vessel co-option with specific examples of vessel co-option in primary and secondary tumors and a consideration of the clinical implications of this alternative tumor blood supply.

Both primary and metastatic tumors use preexisting host tissue vessels as their blood supply. Tumors may grow to a clinically detectable size without angiogenesis and makes them less likely to respond to drugs designed to target the abnormal vasculature produced by angiogenesis, but further studies to explore the biological and clinical implication of these co-opted vessels is needed.

Nanostructured lipid carriers as multifunctional nanomedicine platform for pulmonary co-delivery of anticancer drugs and siRNA

We developed, synthesized, and tested a multifunctional nanostructured lipid nanocarrier-based system (NLCS) for efficient delivery of an anticancer drug and siRNA directly into the lungs by inhalation. The system contains: (1) nanostructured lipid carriers (NLC); (2) anticancer drug (doxorubicin or paclitaxel); (3) siRNA targeted to MRP1 mRNA as a suppressor of pump drug resistance; (4) siRNA targeted to BCL2 mRNA as a suppressor of nonpump cellular resistance and (5) a modified synthetic analog of luteinizing hormone-releasing hormone (LHRH) as a targeting moiety specific to the receptors that are overexpressed in the plasma membrane of lung cancer cells. The NLCS was tested in vitro using human lung cancer cells and in vivo utilizing mouse orthotopic model of human lung cancer. After inhalation, the proposed NLCS effectively delivered its payload into lung cancer cells leaving healthy lung tissues intact and also significantly decreasing the exposure of healthy organs when compared with intravenous injection. The NLCS showed enhanced antitumor activity when compared with intravenous treatment. The data obtained demonstrated high efficiency of proposed NLCS for tumor-targeted local delivery by inhalation of anticancer drugs and mixture of siRNAs specifically to lung cancer cells and, as a result, efficient suppression of tumor growth and prevention of adverse side effects on healthy organs.

Chemotherapeutic sensitization of leptomycin B resistant lung cancer cells by pretreatment with doxorubicin

The development of novel targeted therapies has become an important research focus for lung cancer treatment. Our previous study has shown leptomycin B (LMB) significantly inhibited proliferation of lung cancer cells; however, p53 wild type lung cancer cells were resistant to LMB. Therefore, the objective of this study was to develop and evaluate a novel therapeutic strategy to sensitize LMB-resistant lung cancer cells by combining LMB and doxorubicin (DOX). Among the different treatment regimens, pretreatment with DOX (pre-DOX) and subsequent treatment with LMB to A549 cells significantly decreased the 50% inhibitory concentration (IC50) as compared to that of LMB alone (4.4 nM vs. 10.6 nM, P<0.05). Analysis of cell cycle and apoptosis by flow cytometry further confirmed the cytotoxic data. To investigate molecular mechanisms for this drug combination effects, p53 pathways were analyzed by Western blot, and nuclear proteome was evaluated by two dimensional-difference gel electrophoresis (2D-DIGE) and mass spectrometry. In comparison with control groups, the levels of p53, phospho-p53 (ser15), and p21 proteins were significantly increased while phospho-p53 (Thr55) and survivin were significantly decreased after treatments of pre-DOX and LMB (P<0.05). The 2D-DIGE/MS analysis identified that sequestosome 1 (SQSTM1/p62) had a significant increase in pre-DOX and LMB-treated cells (P<0.05). In conclusion, our results suggest that drug-resistant lung cancer cells with p53 wild type could be sensitized to cell death by scheduled combination treatment of DOX and LMB through activating and restoring p53 as well as potentially other signaling pathway(s) involving sequestosome 1.

[Advances of treatment about elderly clinical stage I non-small cell lung cancer]

随着人口的老龄化, 高龄肺癌患者的比例在增大。近十几年来肺叶切除加纵隔淋巴结清扫一直是Ⅰ期非小细胞肺癌(non small cell lung cancer, NSCLC)患者的标准术式。近年研究发现Ⅰ期高龄NSCLC亚肺叶切除术可以取得和肺叶切除术相当的远期疗效而且可以保留更多的正常肺组织, 有关Ⅰ期NSCLC的标准术式再次引起争议。Ⅰ期高龄NSCLC患者是一个特殊的群体, 常因机体功能减退或合并有基础疾病而无法耐受开胸手术, 胸腔镜的问世以及立体定向放射治疗技术的发展使患者有了更多的选择。Ⅰ期高龄NSCLC的治疗在朝着个体化和多样化方向发展。