Adjuvant Chemotherapy of Lung Cancer: Methodologic Issues and Therapeutic Advances

En bloc chest wall resection in locally advanced cT3N2 (stage IIIB) lung cancer involving the chest wall: Revisiting guidelines

Objectives

Current National Comprehensive Cancer Network guidelines recommend definitive chemoradiation rather than surgery for patients with locally advanced clinical stage T3 and N2 (stage IIIB) lung cancer involving the chest wall. The data supporting this recommendation are controversial. We studied whether surgery confers a survival advantage over definitive chemoradiation in the National Cancer Database.

Methods

We identified all patients with clinical stage T3 and N2 lung cancer in the National Cancer Database from 2004 to 2017 who underwent a lobectomy with en bloc chest wall resection and compared them with patients with clinical stage T3 and N2 lung cancer who had definitive chemoradiation. We used propensity score matching to minimize confounding by indication while excluding patients with tumors in the upper lobes to exclude Pancoast tumors. We used 1:1 propensity score matching and Kaplan-Meir survival analyses to estimate associations.

Results

Of 4467 patients meeting all inclusion/exclusion criteria, 210 (4.49%) had an en bloc chest wall resection. Patients undergoing surgical resection were younger (mean age = 60.3 ± 10.3 years vs 67.5 ± 10.4 years; P < .001) and had more adenocarcinoma (59.0% vs 44.5%; P < .001) but were otherwise similar in terms of sex (37.1% female vs 42.0%; P = .167) and race (Whites 84.3% vs 84.0%; P = .276) compared with the definitive chemoradiation group. After resection, there was an unadjusted 30- and 90-day mortality rate of 3.3% and 9.5%, respectively. A substantial survival benefit with surgical resection persisted after propensity score matching (log-rank P < .001).

Conclusions

In this large observational study, we found that in select patients, en bloc chest wall resection for locally advanced clinical stage T3 and N2 lung cancer was associated with improved survival compared with definitive chemoradiation. National Comprehensive Cancer Network guidelines should be revisited.

Fibronectin promotes tumor progression through integrin αvβ3/PI3K/AKT/SOX2 signaling in non-small cell lung cancer

The tumor microenvironment, especially the extracellular matrix (ECM), is strongly associated with tumor cell proliferation and metastasis. Numerous studies have provided evidence suggesting that fibronectin (FN) in ECM supports cancer cell escape and contributes to cell migration, resulting in distant cancer metastasis and poor outcomes in patients. In our study, it was demonstrated that FN expression was elevated in tumor tissues from highly malignant NSCLC patients, compared to those with low malignancy (p = 0.0076). Importantly, FN promoted proliferative phenotypes and strengthened tumorigenesis capabilities in NSCLC cells, including A549 and Lewis cells, leading to sustained tumor growth in vivo. Mechanistically, it was identified that FN facilitated the activation of the integrin αvβ3/PI3K/AKT signaling pathway, which subsequently upregulated tumor stemness through the downstream transcription factor SOX2. Blockade of integrin αvβ3 signal efficiently suppressed NSCLC proliferation and tumorigenesis both in vitro and in vivo. In conclusion, our study demonstrated that extracellular FN could facilitate NSCLC development through the integrin αvβ3/PI3K/AKT/SOX2 signaling pathway. Blockade of integrin αvβ3 could efficiently enhance the anticancer effects of chemotherapy, offering an innovative approach for clinical NSCLC therapy.

Deep Learning with Multimodal Integration for Predicting Recurrence in Patients with Non-Small Cell Lung Cancer

Due to high recurrence rates in patients with non-small cell lung cancer (NSCLC), medical professionals need extremely accurate diagnostic methods to prevent bleak prognoses. However, even the most commonly used diagnostic method, the TNM staging system, which describes the tumor-size, nodal-involvement, and presence of metastasis, is often inaccurate in predicting NSCLC recurrence. These limitations make it difficult for clinicians to tailor treatments to individual patients. Here, we propose a novel approach, which applies deep learning to an ensemble-based method that exploits patient-derived, multi-modal data. This will aid clinicians in successfully identifying patients at high risk of recurrence and improve treatment planning.

Using Machine Learning Modeling to Explore New Immune-Related Prognostic Markers in Non-Small Cell Lung Cancer

OBJECTIVE

To find new immune-related prognostic markers for non-small cell lung cancer (NSCLC).

METHODS

We found GSE14814 is related to NSCLC in GEO database. The non-small cell lung cancer observation (NSCLC-OBS) group was evaluated for immunity and divided into high and low groups for differential gene screening according to the score of immune evaluation. A single factor COX regression analysis was performed to select the genes related to prognosis. A prognostic model was constructed by machine learning, and test whether the model has a test efficacy for prognosis. A chip-in-chip non-small cell lung cancer chemotherapy (NSCLC-ACT) sample was used as a validation dataset for the same validation and prognostic analysis of the model. The coexpression genes of hub genes were obtained by pearson analysis and gene enrichment, function enrichment and protein interaction analysis. The tumor samples of patients with different clinical stages were detected by immunohistochemistry and the expression difference of prognostic genes in tumor tissues of patients with different stages was compared.

RESULTS

By screening, we found that LYN, C3, COPG2IT1, HLA.DQA1, and TNFRSF17 is closely related to prognosis. After machine learning, we constructed the immune prognosis model from these 5 genes, and the model AUC values were greater than 0.9 at three time periods of 1, 3, and 5 years; the total survival period of the low-risk group was significantly better than that of the high-risk group. The results of prognosis analysis in ACT samples were consistent with OBS groups. The coexpression genes are mainly involved B cell receptor signaling pathway and are mainly enriched in apoptotic cell clearance. Prognostic key genes are highly correlated with PDCD1, PDCD1LG2, LAG3, and CTLA4 immune checkpoints. The immunohistochemical results showed that the expression of COPG2IT1 and HLA.DQA1 in stage III increased significantly and the expression of LYN, C3, and TNFRSF17 in stage III decreased significantly compared with that of stage I. The experimental results are consistent with the previous analysis.

CONCLUSION

LYN, C3, COPG2IT1, LA.DQA1, and NFRSF17 may be new immune markers to judge the prognosis of patients with non-small cell lung cancer.

Upregulation of phosphoserine phosphatase contributes to tumor progression and predicts poor prognosis in non-small cell lung cancer patients

Background

Growing evidence indicates that high phosphoserine phosphatase (PSPH) expression is associated with tumor prognosis in many types of cancers. However, the role of PSPH in non‐small cell lung cancer (NSCLC) is unclear. The purpose of this study was to investigate the clinical significance of PSPH in NSCLC.

Methods

One hundred forty‐three patients with histologically confirmed NSCLC who underwent surgery were included. Quantitative real‐time PCR and Western blot were used to assess PSPH expression in paired tumor and corresponding adjacent non‐tumorous tissues. The role of PSPH in invasion and cell growth was investigated in vitro.

Results

Compared to adjacent normal lung tissues, PSPH messenger RNA and protein levels were significantly higher in NSCLC tissues, and the PSPH expression level was positively related to clinical stage, metastasis, and recurrence. High PSPH expression was predictive of poor overall survival. A549 cells transfected with small interfering‐PSPH showed inhibited cell migration, invasion, and proliferation. We further demonstrated that PSPH might promote the invasive capabilities of NSCLC cells through the AKT/AMPK signaling pathway.

Conclusion

Our results indicate that PSPH may act as a putative oncogene in NSCLC, and may be a vital molecular marker for the metastasis and proliferation of NSCLC cells by regulating the AKT/AMPK signaling pathway.

Aberrant Expression of miR-362 Promotes Lung Cancer Metastasis through Downregulation of Sema3A

miR-362 is a recently discovered member of the microRNA family, and it modulates a variety of physical activities and plays an important role in the occurrence and development of many tumors. However, the biological functions of hsa-miR-362-5p in non-small-cell lung carcinoma (NSCLC) are unknown. Transwell assay and colony formation were used to determine the migration, invasion, and proliferation of NSCLC cells in vitro. A subcutaneous tumor model in nude mice was established to detect NSCLC tumor growth in vivo. The direct binding of miR-362 to the 3'UTR of Semaphorin 3A (Sema3A) was confirmed by luciferase reporter assay. In this study, we found that the level of miR-362 was higher in NSCLC tissues than in adjacent normal tissues and that the level of miR-362 expression was also elevated in five NSCLC cell lines (A549, 95-D, H1299, H292, and H460) relative to a human normal lung epithelial cell line (BEAS2B). Furthermore, miR-362 promoted NSCLC cell invasion, migration, and colony formation in vitro and tumor formation in vivo. Next, we identified the miR-362 target gene Sema3A, which is significantly correlated with metastasis. Sema3A expression was increased in normal tissues relative to NSCLC tissues. This result is consistent with the fact that miR-362 expression is negatively correlated with Sema3A expression in clinical tissue samples and indicated that miR-362 can regulate Sema3A expression in NSCLC cells and consequently affect NSCLC invasion, migration, and colony formation. Taken together, these findings on the newly identified miR-362/Sema3A axis elucidate the molecular mechanism of NSCLC invasion and migration and could lead to a potential therapeutic target in NSCLC treatment.

TBX21 predicts prognosis of patients and drives cancer stem cell maintenance via the TBX21-IL-4 pathway in lung adenocarcinoma

Background

The Th1 cell-specific transcription factor TBX21 functions as a regulator of expression of a Th1 cytokine, interferon gamma (IFN-γ). However, the specific function of TBX21 correlated with cancer stemness remains unclear.

Methods

Using univariate and multivariate survival analysis, TBX21was identified as an independent predictive factor and was associated with poor prognosis in 1389 patients with lung adenocarcinoma (LUAD). Its mechanism in the prognosis was explored by functional enrichment analysis and validated in bioexperiments.

Results

In the training and test sets, TBX21 could classify 1389 LUAD patients into high and low-risk groups with significantly different prognosis (P < 0.01). Its prognostic power was independent of other clinical factors including stage, age, gender and smoking status. Functional studies indicated that downregulating TBX21 in lung cancer cells decreased the fraction of cancer stem cells and their sphere and tumor initiation frequency. Furthermore, the study showed that TBX21 activation transduced a TBX21–IL-4 signaling cascade to promote tumor initiation, tumor growth and expression of stemness markers.

Conclusions

These data demonstrated a key role of TBX21 in the maintenance of cancer stemness and that the TBX21–IL-4 pathway is a crucial factor contributing to lung carcinogenesis.

Graphical abstract

TBX21 prognostic model correlated with cancer stemness via TBX21-IL-4 pathway in LUAD patients

Electronic supplementary material

The online version of this article (10.1186/s13287-018-0820-6) contains supplementary material, which is available to authorized users.

In vitro study of FUZ as a novel potential therapeutic target in non-small-cell lung cancer

FUZ is regarded as a planar cell polarity effector that controls multiple cellular processes during vertebrate development. However, the role of FUZ in tumor biology remains poorly studied. Our purpose of this study is to discover the physiological effects and mechanism of FUZ in non-small-cell lung cancer (NSCLC) in vitro. With the help of bioinformatics analysis, we noticed that the expression level of FUZ negatively correlates with prognosis of NSCLC patients. Exogenous FUZ expression markedly promoted cell proliferation of NSCLC cells. The phosphorylation of Erk1/2, STAT3 and related signaling molecules were induced activated after FUZ over-expression. FUZ also plays an important role in cell motility by regulating cell signaling pathways and inducing epithelial to mesenchymal transition (EMT). FUZ promotes EMT along with the up-regulation of N-cadherin, vimentin, Zeb1, Twist1 and decreased level of E-cadherin. Furthermore, we also carried out FUZ directed siRNA treatments to prove the above observations. Knockdown of FUZ resulted in delayed cell growth as well as impaired cell migration and reversed EMT phonotype. Importantly, we reported for the first time that FUZ is a BNIP3-interacting protein. Loss of FUZ resulted in decreased BNIP3 protein level, but no influence on BNIP3 mRNA level, suggesting weakened stability of BNIP3 protein. Overall, our results in vitro show that FUZ is responsible for NSCLC progression and metastasis, suggesting that FUZ can be a potential therapeutic target for NSCLC.

Role of chemotherapy and targeted therapy in early-stage non-small cell lung cancer

INTRODUCTION

Adjuvant platinum based chemotherapy is accepted as standard of care in stage II and III non-small cell lung cancer (NSCLC) patients and is often considered in patients with stage IB disease who have tumors ≥ 4 cm. The survival advantage is modest with approximately 5% at 5 years. Areas covered: This review article presents relevant data regarding chemotherapy use in the perioperative setting for early stage NSCLC. A literature search was performed utilizing PubMed as well as clinical trial.gov. Randomized phase III studies in this setting including adjuvant and neoadjuvant use of chemotherapy as well as ongoing trials on targeted therapy and immunotherapy are also discussed. Expert commentary: With increasing utilization of screening computed tomography scans, it is possible that the percentage of early stage NSCLC patients will increase in the coming years. Benefits of adjuvant chemotherapy in early stage NSCLC patients remain modest. There is a need to better define patients most likely to derive survival benefit from adjuvant therapy and spare patients who do not need adjuvant chemotherapy due to the toxicity of such therapy. Trials for adjuvant targeted therapy, including adjuvant EGFR-TKI trials and trials of immunotherapy drugs are ongoing and will define the role of these agents as adjuvant therapy.

A novel seven-long non-coding RNA signature predicts survival in early stage lung adenocarcinoma

Increasing evidence has revealed the significant association between dysregulated lncRNA expression and cancers. The prognostic value of lncRNAs in predicting the risk of disease recurrence and identifying high-risk subgroup of early stage lung adenocarcinoma (LUAD) is still unclear. In this study, we analyzed lncRNA expression profiles of 415 early-stage LUAD patients from Gene Expression Omnibus and identified a novel seven-lncRNA signature that was significantly associated with survival in patients with early-stage LUAD (HR = 2.718, CI = 2.054–3.597, p < 0.001). Based on the seven-lncRNA signature, we constructed a risk score model which is able to classify patients of training dataset into the high-risk group and the low-risk group with significantly different clinical outcome (p < 0.001). The robustness of the seven-lncRNA signature was successfully validated through application in other two independent patient datasets. Furthermore, the prognostic value of seven-lncRNA signature was independent of other clinicopathological factors including age, gender, stage and smoking status. Functional analysis suggested that the seven-lncRNA signature may be involved in a variety of biological pathways including cell cycle, ECM-receptor interaction, Focal adhesion and p53 signaling pathway. Taken together, our study not only provides insights into the lncRNA association with LUAD, but also provide alternative molecular markers in prognosis prediction for early-stage LUAD patients.

Combined detection of dickkopf-1 subtype classification autoantibodies as biomarkers for the diagnosis and prognosis of non-small cell lung cancer

Purpose

This study aims to identify the clinical significance of serum autoantibodies against dickkopf-1 (DKK1) and evaluate their feasibility in the immunodiagnosis and prognosis of non-small cell lung cancer (NSCLC).

Experimental design

Epitope mapping by peptide microarray-based serum screening of NSCLC patients (n=72) and healthy controls (n=16) was performed. Indirect ELISA with peptides was used to measure the serum levels of autoantibodies in 206 NSCLC patients and 99 healthy controls. A 3-year follow-up was monitored to evaluate the correlation between serological levels of autoantibodies and overall survival (OS) and progression-free survival (PFS).

Results

Four highly reactive epitopes were identified, which included peptides 67–84 (Pep A), 37–54 (Pep B), 145–156 (Pep C) and 247–261 (Pep D). The autoantibodies levels were considerably higher in sera of NSCLC patients compared with controls (P<0.001), and a highly significant correlation with distant metastases was observed (Pep A: P=0.09, Pep B: P<0.01, Pep C: P<0.01 and Pep D: P<0.01). High levels of antibody subtype to Pep B were remarkably associated with better OS (P=0.004) and PFS (P=0.006). Subsequent Cox regression analysis disclosed that antibody to Pep B was an independent prognostic factor for NSCLC (OS: P=0.008, HR =0.435, 95% CI 0.236–0.802; PFS: P=0.032, HR =0.533, 95% CI 0.322–0.950).

Conclusion

Identified linear epitopes of antigens by peptide microarray are easily available, and subtype classification of DKK1 autoantibodies as novel biomarkers for the diagnosis and prognosis of NSCLC. Our results also highlight the antibody subtype to Pep B as the most valuable biomarker for favorable prognosis of NSCLC.

Phenotypic heterogeneity of potentially curable non-small-cell lung cancer: cohort study with cluster analysis

INTRODUCTION

Significant differences in outcome are observed among lung cancer patients belonging to the same tumor node metastasis stage, suggesting phenotypic heterogeneity beyond this staging algorithm. We used a cluster analysis approach to classify patients into distinct phenotypes, and we attempted to validate the clinical relevance of these phenotypes by comparing outcome.

METHODS

We formed a cohort of all stage I to III non-small-cell lung cancer patients seen between January 2004 and October 2010 in a cancer center and followed until death or last follow-up appointment, with prospectively collected data on clinical and tumor characteristics. Multiple correspondence analysis was followed by hierarchical clustering to form homogenous clusters of patients. Overall survival and disease-free survival estimates were compared among clusters.

RESULTS

The cohort included 367 patients (mean follow-up of 2.5 years), 173 of whom died during that period (191 deaths per 1000 person-years). A four-cluster model was identified, revealing distinct phenotypes with respect to baseline characteristics. Hazard ratios for mortality were 8.1, 5.0, and 3.7 (all statistically significant) for clusters 2, 1, and 3, respectively, when compared with cluster 4-with the most favorable outcome.

CONCLUSION

Staging of patients with non-small-cell lung cancer for prognostic purposes may be improved by considering phenotypes that exhibit significant differences in clinical course and outcome.

miR-99a suppresses the metastasis of human non-small cell lung cancer cells by targeting AKT1 signaling pathway

MicroRNAs (miRNAs) play an important role in the development and progression of non-small cell lung cancer (NSCLC). Recently, several studies have shown that miR-99a is downregulated in various cancers, which can affect tumor initiation and maintenance. Herein, we found that miR-99a was downregulated in NSCLC tissues and suppressed tumor metastasis of NSCLC cells. Down-regulation of miR-99a is significantly associated with last-stage and tumor metastasis in NSCLC patients. Further functional experiments found that overexpression of miR-99a inhibit cell proliferation, migration, and invasion of NSCLC cells in vitro and tumor metastasis of NSCLC in vivo. In addition, we also found that AKT1 is directly involved in miR-99a-mediated tumor suppression. Restored the expression of AKT1 partially abolished the suppressive effects miR-99a on proliferation and invasion of NSCLC cells. Collectively, our data suggest that miR-99a plays an important role in the tumorigenesis and metastasis of NSCLC and may serve as a therapeutic target to avoid dissemination of NSCLC cells.

Decreased expression of miR216a contributes to non-small-cell lung cancer progression

PURPOSE

The aim of the present study is to investigate the role and mechanism of miR216a in non-small-cell lung cancer (NSCLC).

EXPERIMENTAL DESIGN

The expression of miR216a in NSCLC cell lines and from NSCLC patient specimens was measured by real-time qRT-PCR. The correlation between gene expression and patient survival was analyzed using Kaplan-Meier methods. The effects of miR216a on NSCLC cell growth and metastasis were examined both in vitro and in vivo by overexpressing or inhibiting miR216a. Finally, the effect of miR216a on chemoresistance was investigated by MTT assay and flow cytometry.

RESULTS

miR216a expression was downregulated in specimens from patients with NSCLC compared with corresponding nontumor lung tissues. Clinical data indicate that decreased miR216a expression is inversely correlated with cancer stage, metastasis, and poor survival in patients with NSCLC. Our data also show that overexpression of miR216a suppresses NSCLC cell growth and metastasis, and enhances cisplatin-induced cell growth inhibition and apoptosis. In contrast, inhibition of miR216a stimulates NSCLC cell growth and metastasis, and suppresses cisplatin-induced cell growth inhibition and apoptosis. Furthermore, we demonstrate that miR216a exerts its role by directly targeting eIF4B and ZEB1.

CONCLUSION

Our findings suggest that miR216a is a cancer suppressor miRNA and that overexpression of miR216a is a novel NSCLC treatment strategy. In addition, our clinical data indicate that miR216a may be a useful biomarker for predicting NSCLC progression.

miR-137 impairs the proliferative and migratory capacity of human non-small cell lung cancer cells by targeting paxillin

Human lung cancer is the leading cause of cancer motility worldwide, with nearly 1.4 million deaths each year, among which non-small cell lung cancer (NSCLC) accounts for almost 85% of this disease. The discovery of microRNAs (miRNAs) provides a new avenue for NSCLC diagnostic and treatment regiments. Currently, a large number of miRNAs have been reported to be associated with the progression of NSCLC, among which serum miR-137 has been examined to be down-regulated in NSCLC patients. However, the function of miR-137 on NSCLC cells migration and invasion and the relative mechanisms were less known. Here, we found that ectopic expression of miR-137 could inhibit cell proliferation, induce cell apoptosis, and suppress cell migration and invasion in NSCLC cell line A549. Moreover, we found that paxillin (PXN) was a target gene of miR-137 in NSCLC cells and restored expression of PXN abolished the miR-137-mediated suppression of cell migration and invasion. Taken together, our results showed that miR-137 acted as a tumor suppressor in NSCLC by targeting PXN, and it may provide novel diagnostic and therapeutic options for human NSCLC clinical operation in future.

MicroRNA let-7c inhibits migration and invasion of human non-small cell lung cancer by targeting ITGB3 and MAP4K3

MicroRNAs play an important regulatory role in carcinogenesis and cancer metastasis. Different members of let-7 family have been reported to be decreased in human lung tumors. However, the effect of specific let-7 member on metastasis of NSCLC remains undefined. Our current study detected the expression of let-7 members in 94 cases of NSCLC and a significant association was noticed between low levels of let-7c expression and metastasis, venous invasion, advanced TNM stages and poor survival of NSCLC patients. Consistently, ectopic expression of let-7c in relatively highly metastatic cells remarkably suppressed their migration and invasion. Inhibition of let-7c in cells with relatively low metastatic potential promoted their motility and invasion. We then analyzed the potential targets of let-7c and found that ITGB3 and MAP4K3 were directly repressed by let-7c. Upon restoring the expression of ITGB3 and MAP4K3, the effects of let-7c on tumor metastasis were partially reversed, and more importantly, the expression levels of ITGB3 and MAP4K3 were inversely correlated with let-7c in 64 NSCLC tissues. Collectively, our results suggest that let-7c, by degrading ITGB3 and MAP4K3, prevents NSCLC metastasis.

Integrative genomics analysis identifies candidate drivers at 3q26-29 amplicon in squamous cell carcinoma of the lung

PURPOSE

Chromosome 3q26-29 is a critical region of genomic amplification in lung squamous cell carcinomas (SCC). Identification of candidate drivers in this region could help uncover new mechanisms in the pathogenesis and potentially new targets in SCC of the lung.

EXPERIMENTAL DESIGN

We conducted a meta-analysis of seven independent datasets containing a total of 593 human primary SCC samples to identify consensus candidate drivers in 3q26-29 amplicon. Through integrating protein-protein interaction network information, we further filtered for candidates that may function together in a network. Computationally predicted candidates were validated using RNA interference (RNAi) knockdown and cell viability assays. Clinical relevance of the experimentally supported drivers was evaluated in an independent cohort of 52 lung SCC patients using survival analysis.

RESULTS

The meta-analysis identified 20 consensus candidates, among which four (SENP2, DCUN1D1, DVL3, and UBXN7) are involved in a small protein-protein interaction network. Knocking down any of the four proteins led to cell growth inhibition of the 3q26-29-amplified SCC. Moreover, knocking down of SENP2 resulted in the most significant cell growth inhibition and downregulation of DCUN1D1 and DVL3. Importantly, a gene expression signature composed of SENP2, DCUN1D1, and DVL3 stratified patients into subgroups with different response to adjuvant chemotherapy.

CONCLUSION

Together, our findings show that SENP2, DCUN1D1, and DVL3 are candidate driver genes in the 3q26-29 amplicon of SCC, providing novel insights into the molecular mechanisms of disease progression and may have significant implication in the management of SCC of the lung.

Predicting response to chemotherapy with early-stage lung cancer

A recent meta-analysis of 11,107 patients with non-small cell lung cancer who had undergone surgical resection showed that the 5-year survival benefit of adjuvant chemotherapy was 4%, and that of adjuvant chemoradiotherapy was 5%. Two trials have shown a trend toward improved survival with adjuvant paclitaxel plus carboplatin. However, the benefit of adjuvant treatment remains suboptimal. We must distinguish between patients who will not relapse-and who can thus be spared adjuvant treatment-and those who will-for whom adjuvant treatment must be personalized. Several gene expression signatures, generally containing nonoverlapping genes, provide similar predictive information on clinical outcome, and a model combining several signatures did not perform better than did each of the signatures separately. The invasiveness gene signature, containing 186 genes, includes genes involved in the nuclear factor κB pathway, the RAS-mitogen-activated protein kinase pathway, and epigenetic control of gene expression. A 15-gene signature has identified JBR.10 patients who are more sensitive to adjuvant chemotherapy.

Preoperative circulating tumor cell detection using the isolation by size of epithelial tumor cell method for patients with lung cancer is a new prognostic biomarker

PURPOSE

Pathologic TNM staging is currently the best prognostic factor for non-small cell lung carcinoma (NSCLC). However, even in early-stage NSCLC, the recurrence rates after surgery range from 25% to 50%. The preoperative detection of circulating tumor cells (CTC) could be useful to tailor new therapeutic strategies in NSCLC. We assessed the presence of CTC in NSCLC patients undergoing surgery, using cytologic analyses, after their isolation by size of epithelial tumor cells (ISET method). The presence and the number of CTCs were considered and correlated with clinicopathologic parameters including patient follow-up.

EXPERIMENTAL DESIGN

Of the 247 blood samples tested, 208 samples were from patients with resectable NSCLC and 39 from healthy subjects. The mean follow-up was 24 months. An image of detected cells with presumably nonhematologic features [initially defined as "circulating nonhematologic cells" (CNHC)] was recorded. The presence of CNHC was assessed blindly and independently by 10 cytopathologists, using cytologic criteria of malignancy on stained filters. The count of detected CNHCs was made for each filter.

RESULTS

One hundred two of 208 (49%) patients showed CNHCs corresponding to CNHC with malignant cytopathologic features in 76 of 208 (36%) cases. CNHCs were not detected in the control group. A level of 50 or more CNHCs corresponding to the third quartile was associated with shorter overall and disease-free-survival, independently of disease staging, and with a high risk of recurrence and death in early-stage I + II-resectable NSCLC.

CONCLUSION

A high percentage of NSCLC patients show preoperative detection of CNHC by the ISET method. The presence and level of 50 or more CNHCs are associated with worse survival of patients with resectable NSCLC.

Targeted reduction of KLF6-SV1 restores chemotherapy sensitivity in resistant lung adenocarcinoma

Kruppel-like factor 6 splice variant 1 (KLF6-SV1) is an oncogenic splice variant of the KLF6 tumor suppressor gene that is specifically overexpressed in a number of human cancers. Previously, we have demonstrated that increased expression of KLF6-SV1 is associated with decreased survival in lung adenocarcinoma patient samples and that targeted reduction of KLF6-SV1 using siRNA induced apoptosis both alone and in combination with the chemotherapeutic drug cisplatin. Here, we demonstrate that chemoresistant lung cancer cells express increased levels of KLF6-SV1. Furthermore, targeted reduction of KLF6-SV1 using RNA interference restores chemotherapy sensitivity to lung cancer cells both in culture and in vivo through induction of apoptosis. Conversely, overexpression of KLF6-SV1 resulted in a marked reduction in chemotherapy sensitivity in a tumor xenograft model. Combined, these findings highlight a functional role for the KLF6-SV1 splice variant in the regulation of chemotherapy response in lung cancer and could provide novel insight into lung cancer therapy.

A functional role for KLF6-SV1 in lung adenocarcinoma prognosis and chemotherapy response

Kruppel-like factor 6 (KLF6) is a tumor suppressor gene that is functionally inactivated in human cancer by loss of heterozygosity, somatic mutation, decreased expression, and increased alternative splicing into an oncogenic splice variant, KLF6-SV1. Here we show that increased expression of KLF6-SV1 is associated with decreased survival in patients with lung adenocarcinoma. In addition, KLF6-SV1 is a novel antiapoptotic protein in lung cancer cell lines, and targeted reduction of KLF6-SV1 using siRNA induces apoptosis both alone and in combination with the chemotherapeutic drug cisplatin. Together, these findings highlight a critical role for KLF6-SV1 in lung cancer, and show a potential novel therapeutic strategy for the treatment of lung cancer.

BRCA1: a novel prognostic factor in resected non-small-cell lung cancer

BACKGROUND

Although early-stage non-small-cell lung cancer (NSCLC) is considered a potentially curable disease following complete resection, patients have a wide spectrum of survival according to stage (IB, II, IIIA). Within each stage, gene expression profiles can identify patients with a higher risk of recurrence. We hypothesized that altered mRNA expression in nine genes could help to predict disease outcome: excision repair cross-complementing 1 (ERCC1), myeloid zinc finger 1 (MZF1) and Twist1 (which regulate N-cadherin expression), ribonucleotide reductase subunit M1 (RRM1), thioredoxin-1 (TRX1), tyrosyl-DNA phosphodiesterase (Tdp1), nuclear factor of activated T cells (NFAT), BRCA1, and the human homolog of yeast budding uninhibited by benzimidazole (BubR1).

METHODOLOGY AND PRINCIPAL FINDINGS

We performed real-time quantitative polymerase chain reaction (RT-QPCR) in frozen lung cancer tissue specimens from 126 chemonaive NSCLC patients who had undergone surgical resection and evaluated the association between gene expression levels and survival. For validation, we used paraffin-embedded specimens from 58 other NSCLC patients. A strong inter-gene correlation was observed between expression levels of all genes except NFAT. A Cox proportional hazards model indicated that along with disease stage, BRCA1 mRNA expression significantly correlated with overall survival (hazard ratio [HR], 1.98 [95% confidence interval (CI), 1.11-6]; P = 0.02). In the independent cohort of 58 patients, BRCA1 mRNA expression also significantly correlated with survival (HR, 2.4 [95%CI, 1.01-5.92]; P = 0.04).

CONCLUSIONS

Overexpression of BRCA1 mRNA was strongly associated with poor survival in NSCLC patients, and the validation of this finding in an independent data set further strengthened this association. Since BRCA1 mRNA expression has previously been linked to differential sensitivity to cisplatin and antimicrotubule drugs, BRCA1 mRNA expression may provide additional information for customizing adjuvant antimicrotubule-based chemotherapy, especially in stage IB, where the role of adjuvant chemotherapy has not been clearly demonstrated.

Adjuvant vinorelbine plus cisplatin versus observation in patients with completely resected stage IB-IIIA non-small-cell lung cancer (Adjuvant Navelbine International Trialist Association [ANITA]): a randomised controlled trial

BACKGROUND

Whether adjuvant chemotherapy improves survival of patients with non-small-cell lung cancer (NSCLC) is not known. We aimed to compare the effect of adjuvant vinorelbine plus cisplatin versus observation on survival in patients with completely resected NSCLC.

METHODS

840 patients with stage IB-IIIA NSCLC from 101 centres in 14 countries were randomly assigned to observation (n=433) or to 30 mg/m(2) vinorelbine plus 100 mg/m(2) cisplatin (n=407). Postoperative radiotherapy was not mandatory and was undertaken according to every centre's policy. The primary endpoint was overall survival. Analysis was by intention to treat. This trial is registered as an International Standard Randomised Controlled Trial, number ISRCTN95053737.

FINDINGS

367 patients in the chemotherapy group and 431 in the control group received their assigned treatment. 301 (36%) patients had stage IB disease, 203 (24%) had stage II disease, and 325 (39%) had stage IIIA disease. Tolerance to chemotherapy mainly included neutropenia in 335 (92%) patients and febrile neutropenia in 34 (9%); seven (2%) toxic deaths were also recorded. Compliance was greater with cisplatin than with vinorelbine (median dose intensity 89% [range 17-108] vs 59% [17-100]). After a median follow-up of 76 months (range 43-116), median survival was 65.7 months (95% CI 47.9-88.5) in the chemotherapy group and 43.7 (35.7-52.3) months in the observation group. Adjusted risk for death was significantly reduced in patients assigned chemotherapy compared with controls (hazard ratio 0.80 [95% CI 0.66-0.96]; p=0.017). Overall survival at 5 years with chemotherapy improved by 8.6%, which was maintained at 7 years (8.4%).

INTERPRETATION

Adjuvant vinorelbine plus cisplatin extends survival in patients with completely resected NSCLC, better defining indication of adjuvant chemotherapy.