The role of RAS oncogene in survival of patients with lung cancer: a systematic review of the literature with meta-analysis

High expression of Bcl-2 protein predicts favorable outcome in non-small cell lung cancer: evidence from a systematic review and meta-analysis

BACKGROUND

The prognostic value of Bcl-2 protein expression in non-small cell lung cancer (NSCLC) is under debate. We therefore systematically reviewed the evidence for Bcl-2 protein effects on NSCLC survival to elucidate this issue.

MATERIALS AND METHODS

An electronic search in Pubmed and Embase complemented by manual searches in article references were conducted to identify eligible studies to evaluate the association between Bcl-2 protein expression and overall survival (OS) as well as disease free survival (DFS) of NSCLC patients. Combined hazard ratios (HRs) with corresponding 95% confidence intervals (95%CIs) were pooled using the random-effects model.

RESULTS

A total of 50 trials (including 52 cohorts) encompassing 7,765 patients were pooled in the meta-analysis regarding Bcl-2 expression and OS of NSCLC patients. High expression of Bcl-2 protein had a favorable impact (HR=0.76, 95%CI=0.67-0.86). In the group of Bcl-2 expression and DFS, 11 studies including 2,634 patients were included. The synthesized result indicated high expression of Bcl-2 protein might predict good DFS (HR=0.85, 95%CI=0.75-0.95).

CONCLUSIONS

Our present meta-analysis demonstrated favorable prognostic values of Bcl-2 expression in patients with NSCLC. Further prospective trails are welcomed to validate the utility of assessing Bcl-2 in NSCLC patient management.

Impact of KRAS codon subtypes from a randomised phase II trial of selumetinib plus docetaxel in KRAS mutant advanced non-small-cell lung cancer

BACKGROUND

Selumetinib (AZD6244, ARRY-142886)+docetaxel increases median overall survival (OS) and significantly improves progression-free survival (PFS) and objective response rate (ORR) compared with docetaxel alone in patients with KRAS mutant, stage IIIB/IV non-small-cell lung cancer (NSCLC; NCT00890825).

METHODS

Retrospective analysis of OS, PFS, ORR and change in tumour size at week 6 for different sub-populations of KRAS codon mutations.

RESULTS

In patients receiving selumetinib+docetaxel and harbouring KRAS G12C or G12V mutations there were trends towards greater improvement in OS, PFS and ORR compared with other KRAS mutations.

CONCLUSION

Different KRAS mutations in NSCLC may influence selumetinib/docetaxel sensitivity.

The comparison between dual inhibition of mTOR with MAPK and PI3K signaling pathways in KRAS mutant NSCLC cell lines

KRAS mutations are found in 15-25 % of patients with lung adenocarcinoma, and they lead to constitutive activation of KRAS signaling pathway that results in sustained cell proliferation. Currently, there are no direct anti-KRAS therapies available. Therefore, it is rational to target the downstream molecules of KRAS signaling pathway, which are mitogen-activated protein kinase (MAPK) signaling pathway (RAF-MEK-ERK) and PI3K pathway (PI3K-AKT-mTOR). Here, we examined the inhibition of both these pathways alone and in combination and analyzed the anti-proliferative and apoptotic events in KRAS mutant NSCLC cell lines, A549 and Calu-1. Cytotoxicity was determined by MTT assay after the cells were treated with LY294002 (PI3K inhibitor), U0126 (MEK inhibitor), and RAD001 (mTOR inhibitor) for 24 and 48 h. The expression levels of p-ERK, ERK, AKT, p-AKT, p53, cyclinD1, c-myc, p27(kip1), BAX, BIM, and GAPDH were detected by western blot after 6 and 24 h treatment. Although PI3K/mTOR inhibition is more effective in cytotoxicity in A549 and Calu-1 cells, MEK/mTOR inhibition markedly decreases cell proliferation protein marker expressions. Our data show that combined targeting of MEK and PI3K-AKT with mTOR is a better option than single agents alone for KRAS mutant NSCLC, thus opening the possibility of a beneficial treatment strategy in the future.

Targeted Therapies in Non-Small Cell Lung Cancer-Beyond EGFR and ALK

Systemic therapy for non-small cell lung cancer (NSCLC) has undergone a dramatic paradigm shift over the past decade. Advances in our understanding of the underlying biology of NSCLC have revealed distinct molecular subtypes. A substantial proportion of NSCLC depends on oncogenic molecular aberrations (so-called "driver mutations") for their malignant phenotype. Personalized therapy encompasses the strategy of matching these subtypes with effective targeted therapies. EGFR mutations and ALK translocation are the most effectively targeted oncogenes in NSCLC. EGFR mutations and ALK gene rearrangements are successfully being targeted with specific tyrosine kinase inhibitors. The number of molecular subgroups of NSCLC continues to grow. The scope of this review is to discuss recent data on novel molecular targets as ROS1, BRAF, KRAS, HER2, c-MET, RET, PIK3CA, FGFR1 and DDR2. Thereby the review will focus on therapeutic strategies targeting these aberrations. Moreover, the emerging challenge of acquired resistance to initially effective therapies will be discussed.

Enhanced MET Translation and Signaling Sustains K-Ras-Driven Proliferation under Anchorage-Independent Growth Conditions

Oncogenic K-Ras mutation occurs frequently in several types of cancers, including pancreatic and lung cancers. Tumors with K-Ras mutation are resistant to chemotherapeutic drugs as well as molecular targeting agents. Although numerous approaches are ongoing to find effective ways to treat these tumors, there are still no effective therapies for K-Ras mutant cancer patients. Here we report that K-Ras mutant cancers are more dependent on K-Ras in anchorage-independent culture conditions than in monolayer culture conditions. In seeking to determine mechanisms that contribute to the K-Ras dependency in anchorage-independent culture conditions, we discovered the involvement of Met in K-Ras-dependent, anchorage-independent cell growth. The Met signaling pathway is enhanced and plays an indispensable role in anchorage-independent growth even in cells in which Met is not amplified. Indeed, Met expression is elevated under anchorage-independent growth conditions and is regulated by K-Ras in a MAPK/ERK kinase (MEK)-dependent manner. Remarkably, in spite of a global downregulation of mRNA translation during anchorage-independent growth, we find that Met mRNA translation is specifically enhanced under these conditions. Importantly, ectopic expression of an active Met mutant rescues K-Ras ablation-derived growth suppression, indicating that K-Ras-mediated Met expression drives "K-Ras addiction" in anchorage-independent conditions. Our results indicate that enhanced Met expression and signaling is essential for anchorage-independent growth of K-Ras mutant cancer cells and suggests that pharmacological inhibitors of Met could be effective for K-Ras mutant tumor patients.

The prognostic impact of KRAS, its codon and amino acid specific mutations, on survival in resected stage I lung adenocarcinoma

BACKGROUND

Despite complete surgical resection, patients with stage I non-small-cell lung cancer (NSCLC) are at risk for disease recurrence. The impact of common oncogenic driver mutations on prognosis in stage I NSCLC is limited. The pure prognostic value of KRAS mutational status was explored in resected stage I lung adenocarcinoma.

METHODS

Mutation status was tested in patients who had complete resection of stage I lung adenocarcinoma without any adjuvant therapy, using a multiplex polymerase chain reaction)-based assay. Disease-free survival (DFS) and overall survival (OS) were compared between patients with KRAS-mutant (KRAS-MUT), KRAS-MUT subtypes, and KRAS wild-type (KRAS-WT) tumors.

RESULTS

A total of 312 patients were included in this analysis; 127 harbored KRAS mutations and 185 had KRAS-WT tumors. When compared with KRAS-WT, KRAS-MUT was associated with significantly shorter OS (hazard ratio 4.36, 95% confidence interval 2.09-9.07; p < 0.0001) and DFS (hazard ratio 3.62, 95% confidence interval 2.11-6.22; p < 0.0001). When stratifying KRAS-WT patients based on EGFR status, KRAS-MUT patients had worse OS (p = 0.0001) and DFS (p < 0.0001) than patients with EGFR-MUT and EGFR-WT/KRAS-WT (WT/WT). Patients with codon 12 mutations had superior DFS (p = 0.0314), but there were no differences in OS compared with mutations found in codons 13 and 61 (p = 0.1772). We observed better DFS associated with G12C/G12V mutations compared with other amino acid specific KRAS mutations (p = 0.0271) with a trend towards improved OS (p = 0.0636). Multivariate analysis identified KRAS mutation as independent predictor of worse OS (p = 0.001) and DFS (p < 0.0001).

CONCLUSION

KRAS is an independent prognostic marker in resected stage I lung adenocarcinoma. Differential outcomes are associated with codon and amino acid specific KRAS mutations.

PD-L1 over-expression and survival in patients with non-small cell lung cancer: a meta-analysis

BACKGROUND

Observational studies on the prognostic role of programmed cell death-ligand 1 (PD-L1) in non-small cell lung cancer (NSCLC) are controversial.

METHODS

To clarify the impact of PD-L1 in NSCLC survival, we performed this meta-analysis that included eligible studies. The combined hazard ratios (HR) and their corresponding 95% confidence intervals (CIs) were calculated in terms of overall survival.

RESULTS

A total of five studies with 877 patients were evaluable for this meta-analysis. Our results suggested that PD-L1 overexpression had a poor impact on survival of patients with NSCLC, the HR (95% CI) was 1.43 (1.24-1.63) overall, 1.51 (1.24-1.7954) in Asian patients, 1.35 (1.08-1.63) in non-Asian patients. Moreover, there was no heterogeneity between the studies.

CONCLUSIONS

PD-L1 overexpression indicates a poor prognosis for patients with NSCLC.

Prognostic markers in lung cancer: is it ready for prime time?

Non-small cell lung cancer (NSCLC) is a heterogeneity disease and to date, specific clinical factors and tumor stage are established as prognostic markers. Nevertheless, prognosis within stage may vary significantly. During the last 3 decades, genes/proteins that drive tumor initiation and progression, such as oncogenes and tumor suppressor genes have been studied as additional potential prognostic markers. The protein markers as evaluated by immunohistochemistry (IHC) have previously dominated these studies. However, with the development of high-throughput techniques to interrogate genome wide genetic or gene expression changes, DNA (copy number and mutation) and RNA (mRNA and microRNA) based markers have more recently been studied as prognostic markers. Largely due to the heterogeneity and complexity of NSCLC, single gene markers including KRAS mutation has not been validated as strong prognostic markers. In contrast, several gene expression signatures representing mRNA levels of multiple genes have been developed and validated in multiple microarray datasets of independent patient cohorts. The salient features of these gene signatures and their potential value to predict benefit from adjuvant chemotherapy is discussed.

Are we ready to use biomarkers for staging, prognosis and treatment selection in early-stage non-small-cell lung cancer?

Lung cancer accounts for the majority of cancer-related deaths worldwide. At present, platinum-based therapy represents the standard of care in fit stage II and IIIA non-small cell lung cancer (NSCLC) patients following surgical resection. In advanced disease, personalized chemotherapy and targeted biologic therapy based on histological and molecular tumor profiling have already shown promise in terms of optimizing treatment efficacy. While disease stage is associated with outcome and is commonly used to determine adjuvant treatment eligibility, it is known that a subset of patients with early stage disease experience shorter survival than others with the same clinicopathological characteristics. Improved methods for identifying these individuals, at or near the time of initial diagnosis, may inform the decision to pursue adjuvant therapy options. Among the numerous candidate molecular biomarkers, only few gene-expression profiling signatures provide clinically relevant information, while real-time quantitative polymerase-chain reaction (RT-qPCR) strategy involving relatively small numbers of genes offers a practical alternative with high cross-platform performance. mRNA and/or protein expression levels of excision repair cross-complementation group 1 (ERCC1), ribonucleotide reductase M subunit 1 (RRM1) and breast cancer susceptibility gene 1 (BRCA1) are among the most promising potential biomarkers for early disease and their clinical utility is currently being evaluated in randomized phase II and III clinical trials. This review describes the most promising clinicopathological and molecular biomarkers with predictive and prognostic significance in lung cancer that have been identified through advanced research and which could influence adjuvant and neoadjuvant chemotherapy decisions for operable NSCLC in routine clinical practice.

KRAS mutation as the biomarker of response to chemotherapy and EGFR-TKIs in patients with advanced non-small cell lung cancer: clues for its potential use in second-line therapy decision making

OBJETIVE

In patients with non-small cell lung cancer (NSCLC), knowledge of the epidermal growth factor receptor (EGFR) mutation status is fundamental for selecting the treatment involving EGFR-tyrosine kinase inhibitors (EGFR-TKIs). Little information is available regarding the response and progression-free survival (PFS) in platinum-based chemotherapy (CT) versus EGFR-TKIs in the presence or absence of KRAS mutation, particularly in patients without EGFR mutation.

METHODS

From 2007 to 2010, 353 patients with NSCLC were treated with first-line CT, EGFR-TKIs were used in the second or third line of treatment. Tests were performed for EGFR and KRAS mutation and the results of the mutations were obtained 3 to 4 months after the start of the treatment. We analyzed clinical characteristics, mutation profile, response and PFS to CT and EGFR-TKIs, and overall survival. The protocol is registered with ClinicalTrials.gov, number NCT01023828.

RESULTS

Presence of the wild-type (WT) KRAS was independently associated with increased response rate to first-line CT when compared with KRAS mutation (41.4% vs. 14.7%; P=0.001). The EGFR mutation (57.8% vs. 11.7%; P<0.001) and WT-KRAS (39.6% vs. 3.3%; P=0.001) were associated with the EGFR-TKIs response. PFS of patients with WT-EGFR and KRAS mutation treated with EGFR-TKIs was shorter when compared with patients with WT-EGFR and WT-KRAS (P<0.001).

CONCLUSIONS

KRAS mutation status is a good biomarker for response to EGFR-TKIs in patients with NSCLC. KRAS mutational status could impact the decision to give CT or EGFR-TKIs as a second line of treatment to patients with NSCLC, particularly in patients with WT-EGFR.

Germline polymorphisms and survival of lung adenocarcinoma patients: a genome-wide study in two European patient series

In lung cancer, the survival of patients with the same clinical stage varies widely for unknown reasons. In this two-phase study, we examined the hypothesis that germline variations influence the survival of patients with lung adenocarcinoma. First, we analyzed existing genotype and clinical data from 289 UK-resident patients with lung adenocarcinoma, identifying 86 single nucleotide polymorphisms (SNPs) that associated with survival (p < 0.01). We then genotyped these candidate SNPs in a validation series of 748 patients from Italy that resulted genetically compatible with the UK series based on principal component analysis. In a Cox proportional hazard model adjusted for age, sex and clinical stage, four SNPs were confirmed on the basis of their having a hazard ratio (HR) indicating the same direction of effect in the two series and p < 0.05. The strongest association was provided by rs2107561, an intronic SNP of PTPRG, protein tyrosine phosphatase, receptor type, G; the C allele was associated with poorer survival in both patient series (pooled analysis loge HR = 0.31; 95% CI: 0.15-0.46, p = 8.5 × 10(-5) ). PTPRG mRNA levels in 43 samples of lung adenocarcinoma were 40% of those observed in noninvolved lung tissue from the same patients. PTPRG overexpression significantly inhibited the clonogenicity of A549 lung carcinoma cells and the anchorage-independent growth of the NCI-H460 large cell lung cancer line. These four germline variants represent promising candidates that, with further study, may help predict clinical outcome. In addition, the PTPRG locus may have a role in tumor progression.

A randomized phase II study of the MEK1/MEK2 inhibitor trametinib (GSK1120212) compared with docetaxel in KRAS-mutant advanced non-small-cell lung cancer (NSCLC)†

BACKGROUND

KRAS mutations are detected in 25% of non-small-cell lung cancer (NSCLC) and no targeted therapies are approved for this subset population. Trametinib, a selective allosteric inhibitor of MEK1/MEK2, demonstrated preclinical and clinical activity in KRAS-mutant NSCLC. We report a phase II trial comparing trametinib with docetaxel in patients with advanced KRAS-mutant NSCLC.

PATIENTS AND METHODS

Eligible patients with histologically confirmed KRAS-mutant NSCLC previously treated with one prior platinum-based chemotherapy were randomly assigned in a ratio of 2 : 1 to trametinib (2 mg orally once daily) or docetaxel (75 mg/m(2) i.v. every 3 weeks). Crossover to the other arm after disease progression was allowed. Primary end point was progression-free survival (PFS). The study was prematurely terminated after the interim analysis of 92 PFS events, which showed the comparison of trametinib versus docetaxel for PFS crossed the futility boundary.

RESULTS

One hundred and twenty-nine patients with KRAS-mutant NSCLC were randomized; of which, 86 patients received trametinib and 43 received docetaxel. Median PFS was 12 weeks in the trametinib arm and 11 weeks in the docetaxel arm (hazard ratio [HR] 1.14; 95% CI 0.75-1.75; P = 0.5197). Median overall survival, while the data are immature, was 8 months in the trametinib arm and was not reached in the docetaxel arm (HR 0.97; 95% CI 0.52-1.83; P = 0.934). There were 10 (12%) partial responses (PRs) in the trametinib arm and 5 (12%) PRs in the docetaxel arm (P = 1.0000). The most frequent adverse events (AEs) in ≥20% of trametinib patients were rash, diarrhea, nausea, vomiting, and fatigue. The most frequent grade 3 treatment-related AEs in the trametinib arm were hypertension, rash, diarrhea, and asthenia.

CONCLUSION

Trametinib showed similar PFS and a response rate as docetaxel in patients with previously treated KRAS-mutant-positive NSCLC.

CLINICALTRIALSGOV REGISTRATION NUMBER

NCT01362296.

Prognostic value of TTF-1 expression in patients with non-small cell lung cancer: A meta-analysis

BACKGROUND

Observational studies on the prognostic role of thyroid transcription factor 1 (TTF-1) in non-small-cell lung cancer (NSCLC) are controversial.

METHODS

To clarify the impact of TTF-1 in NSCLC survival, we performed this meta-analysis that included eligible studies. The combined hazard ratios and their corresponding 95% confidence intervals were calculated in terms of overall survival.

RESULTS

A total of 17 studies with 2235 patients were evaluable for this meta-analysis. The studies were categorized by histology, disease stage and patient race. Our results suggested that TTF-1 overexpression had a favorable impact on survival of patients with NSCLC, the HR (95% CI) was 0.49 (0.42 to 0.55) overall, 0.46 (0.38-0.54) in Asian patients, 0.52 (0.42-0.63) in non-Asian patients, 0.45 (0.38-0.52) in adenocarcinoma, 0.63 (0.39-0.86) in stage I NSCLC, and 0.43 (0.33-0.53) in stage IIIb-IV NSCLC. The data collected were not sufficient to determine the prognostic value of VEGF in patients with squamous cell lung carcinomas. But there was a high heterogeneity between the studies.

CONCLUSION

TTF-1 overexpression indicates a favorable prognosis for patients with NSCLC, this effect appears also significant when the analysis is restricted in lung AC patients, stage I and stage IIIb-IV NSCLC.

Integrating RAS status into prognostic signatures for adenocarcinomas of the lung

PURPOSE

While the dysregulation of specific pathways in cancer influences both treatment response and outcome, few current prognostic markers explicitly consider differential pathway activation. Here we explore this concept, focusing on K-Ras mutations in lung adenocarcinoma (present in 25%-35% of patients).

EXPERIMENTAL DESIGN

The effect of K-Ras mutation status on prognostic accuracy of existing signatures was evaluated in 404 patients. Genes associated with K-Ras mutation status were identified and used to create a RAS pathway activation classifier to provide a more accurate measure of RAS pathway status. Next, 8 million random signatures were evaluated to assess differences in prognosing patients with or without RAS activation. Finally, a prognostic signature was created to target patients with RAS pathway activation.

RESULTS

We first show that K-Ras status influences the accuracy of existing prognostic signatures, which are effective in K-Ras-wild-type patients but fail in patients with K-Ras mutations. Next, we show that it is fundamentally more difficult to predict the outcome of patients with RAS activation (RAS(mt)) than that of those without (RAS(wt)). More importantly, we demonstrate that different signatures are prognostic in RAS(wt) and RAS(mt). Finally, to exploit this discovery, we create separate prognostic signatures for RAS(wt) and RAS(mt) patients and show that combining them significantly improves predictions of patient outcome.

CONCLUSIONS

We present a nested model for integrated genomic and transcriptomic data. This model is general and is not limited to lung adenocarcinomas but can be expanded to other tumor types and oncogenes.

Contributions of KRAS and RAL in non-small-cell lung cancer growth and progression

INTRODUCTION

KRAS mutations are poor prognostic markers for patients with non-small-cell lung cancer (NSCLC). RALA and RALB GTPases lie downstream of RAS and are implicated in RAS-mediated tumorigenesis. However, their biological or prognostic role in the context of KRAS mutation in NSCLC is unclear.

METHODS

Using expression analysis of human tumors and a panel of cell lines coupled with functional in vivo and in vitro experiments, we evaluated the prognostic and functional importance of RAL in NSCLC and their relationship to KRAS expression and mutation.

RESULTS

Immunohistochemical (N = 189) and transcriptomic (N = 337) analyses of NSCLC patients revealed high RALA and RALB expression was associated with poor survival. In a panel of 14 human NSCLC cell lines, RALA and RALB had higher expression in KRAS mutant cell lines whereas RALA but not RALB activity was higher in KRAS mutant cell lines. Depletion of RAL paralogs identified cell lines that are dependent on RAL expression for proliferation and anchorage independent growth. Overall, growth of NSCLC cell lines that carry a glycine to cystine KRAS mutation were more sensitive to RAL depletion than those with wild-type KRAS. The use of gene expression and outcome data from 337 human tumors in RAL-KRAS interaction analysis revealed that KRAS and RAL paralog expression jointly impact patient prognosis.

CONCLUSION

RAL GTPase expression carries important additional prognostic information to KRAS status in NSCLC patients. Simultaneously targeting RAL may provide a novel therapeutic approach in NSCLC patients harboring glycine to cystine KRAS mutations.

Prognostic significance of EGFR and KRAS mutations in NSCLC patients with brain metastases treated with radiosurgery†

PURPOSE

Determine whether EGFR and KRAS mutations carry prognostic significance in non-small cell lung cancer (NSCLC) patients with brain metastases treated with stereotactic radiosurgery.

METHODS AND MATERIALS

Ninety-four NSCLC patients with brain metastases initially treated with stereotactic radiosurgery were retrospectively reviewed. Both EGFR and KRAS mutation status were recorded in 67 patients: EGFR+/KRAS- status in 9 patients, EGFR-/KRAS+ in 15 patients, and EGFR-/KRAS- in 43 patients. Survival was determined using the Kaplan-Meier method. Cox regression was used to assess the effects of patient factors on overall survival, local control, and distant brain control - all from time of brain metastasis diagnosis.

RESULTS

Median overall survival from time of brain metastasis diagnosis was 30.6 months for EGFR+/KRAS- patients, 9.8 months for EGFR-/KRAS+ patients, and 19.1 months for EGFR-/KRAS- patients (p=0.094). Local control at 2 years was 100% for EGFR+/KRAS- patients, 66.7% for EGFR-/KRAS+ patients, and 97.2% for EGFR-/KRAS- patients (p=0.399). Distant brain control at 12 months was achieved in 66.7% of EGFR+/KRAS- patients, 30.0% of EGFR-/KRAS+ patients, and 73.7% of EGFR-/KRAS- patients (p=0.039). On multivariate analysis, the most important predictors of mortality were baseline DS-GPA>2 (HR=0.27; p=0.001), EGFR mutation positivity (HR=0.30; p=0.054), and KRAS mutation positivity (HR=2.12; p=0.056); the most important predictors of distant brain failure were KRAS status (HR=4.44; p=0.004) and extracranial disease (HR=3.28; p=0.058); there was no statistically significant multivariate model identified for local control.

CONCLUSIONS

In NSCLC patients with brain metastases, KRAS mutations portend higher rates of distant brain failure. Our data also suggests that EGFR portends better overall survival and KRAS portends worse overall survival, though this still needs to be verified by a larger study.

Molecularly targeted therapies in non-small-cell lung cancer annual update 2014

There have been significant advances in the understanding of the biology and treatment of non-small-cell lung cancer (NSCLC) during the past few years. A number of molecularly targeted agents are in the clinic or in development for patients with advanced NSCLC. We are beginning to understand the mechanisms of acquired resistance after exposure to tyrosine kinase inhibitors in patients with oncogene addicted NSCLC. The advent of next-generation sequencing has enabled to study comprehensively genomic alterations in lung cancer. Finally, early results from immune checkpoint inhibitors are very encouraging. This review summarizes recent advances in the area of cancer genomics, targeted therapies, and immunotherapy.

Emerging understanding of multiscale tumor heterogeneity

Cancer is a multifaceted disease characterized by heterogeneous genetic alterations and cellular metabolism, at the organ, tissue, and cellular level. Key features of cancer heterogeneity are summarized by 10 acquired capabilities, which govern malignant transformation and progression of invasive tumors. The relative contribution of these hallmark features to the disease process varies between cancers. At the DNA and cellular level, germ-line and somatic gene mutations are found across all cancer types, causing abnormal protein production, cell behavior, and growth. The tumor microenvironment and its individual components (immune cells, fibroblasts, collagen, and blood vessels) can also facilitate or restrict tumor growth and metastasis. Oncology research is currently in the midst of a tremendous surge of comprehension of these disease mechanisms. This will lead not only to novel drug targets but also to new challenges in drug discovery. Integrated, multi-omic, multiplexed technologies are essential tools in the quest to understand all of the various cellular changes involved in tumorigenesis. This review examines features of cancer heterogeneity and discusses how multiplexed technologies can facilitate a more comprehensive understanding of these features.

KRAS protein stability is regulated through SMURF2: UBCH5 complex-mediated β-TrCP1 degradation

Attempts to target mutant KRAS have been unsuccessful. Here, we report the identification of Smad ubiquitination regulatory factor 2 (SMURF2) and UBCH5 as a critical E3:E2 complex maintaining KRAS protein stability. Loss of SMURF2 either by small interfering RNA/short hairpin RNA (siRNA/shRNA) or by overexpression of a catalytically inactive mutant causes KRAS degradation, whereas overexpression of wild-type SMURF2 enhances KRAS stability. Importantly, mutant KRAS is more susceptible to SMURF2 loss where protein half-life decreases from >12 hours in control siRNA-treated cells to <3 hours on Smurf2 silencing, whereas only marginal differences were noted for wild-type protein. This loss of mutant KRAS could be rescued by overexpressing a siRNA-resistant wild-type SMURF2. Our data further show that SMURF2 monoubiquitinates UBCH5 at lysine 144 to form an active complex required for efficient degradation of a RAS-family E3, β-transducing repeat containing protein 1 (β-TrCP1). Conversely, β-TrCP1 is accumulated on SMURF2 loss, leading to increased KRAS degradation. Therefore, as expected, β-TrCP1 knockdown following Smurf2 siRNA treatment rescues mutant KRAS loss. Further, we identify two conserved proline (P) residues in UBCH5 critical for SMURF2 interaction; mutation of either of these P to alanine also destabilizes KRAS. As a proof of principle, we demonstrate that Smurf2 silencing reduces the clonogenic survival in vitro and prolongs tumor latency in vivo in cancer cells including mutant KRAS-driven tumors. Taken together, we show that SMURF2:UBCH5 complex is critical in maintaining KRAS protein stability and propose that targeting such complex may be a unique strategy to degrade mutant KRAS to kill cancer cells.

Molecular diagnostic testing of cytology specimens: current applications and future considerations

Molecular mechanisms of pathogenesis continue to be discovered, accelerating significant expansion of the spectrum of clinically useful molecular diagnostic tests and their incorporation into patient care algorithms. Currently, molecular assays facilitate identification of infectious processes, detection of specific constitutional and somatically acquired pathogenic mutations, guidance of therapy selection, and monitoring of treatment response and disease progression. The correlation of genomic test results with clinical, morphologic, and immunophenotypic findings has defined the practice of "precision medicine" with wide-reaching implications for health care. As novel promising techniques such as microarrays and next-generation sequencing are adopted by health care providers, new practice standards are being developed for incorporation into practice. Cytology specimens are good sources of high-quality nucleic acids. Although sometimes limited in quantity, in many cases such specimens are well suited for molecular diagnostic testing, which is capable of maximizing the number of tests from small amounts of sample. The pathologist continues to serve as a central resource for diagnostic testing and consultation regarding appropriate use of molecular tests. Understanding current methodologies, clinical utility of currently available nucleic acid tests, validation requirements for test implementation, quality assurance metrics, and future technology trends is essential to the practice of contemporary molecular pathology.

Implementing the new IASLC/ATS/ERS classification of lung adenocarcinomas: results from international and Chinese cohorts

A new histologic classification of lung adenocarcinoma was proposed by the International Association for the Study of Lung Cancer, American Thoracic Society, and European Respiratory Society (IASLC/ATS/ERS) in 2011 to provide uniform terminology and diagnostic criteria for multidisciplinary strategic management. This classification proposed a comprehensive histologic subtyping (lepidic, acinar, papillary, micropapillary, and solid pattern) and a semi-quantitative assessment of histologic patterns (in 5% increments) in an effort to choose a single, predominant pattern in invasive adenocarcinomas. The prognostic value of this classification has been validated in large, independent cohorts from multiple countries. In patients who underwent curative-intent surgery, those with either an adenocarcinoma in situ (AIS) or a minimal invasive adenocarcinoma have nearly 100% disease-free survival and are designated "low grade tumors". For invasive adenocarcinomas, the acinar and papillary predominant histologic subtypes were usually designated as "intermediate grade" while the solid and micropapillary predominant histologic subtypes were designated "high grade" tumors; this was based on the statistic difference of overall survival. This classification, coupled with additional prognostic factors [nuclear grade, cribriform pattern, high Ki-67 labeling index, thyroid transcription factor-1 (TTF-1) immunohistochemistry, immune markers, and (18)F-fluorodeoxyglucose uptake on positron emission tomography (PET)] that we have published on, could further stratify patients into prognostic subgroups and may prove helpful for individual patient care. With regard to Chinese oncologists, the implementation of this new classification only requires hematoxylin and eosin (H&E) stained slides and basic pathologic training, both of which require no additional costs. More importantly, this new classification system could provide informative data for better selection and stratification of clinical trials and molecular studies.

BYL719, a selective inhibitor of phosphoinositide 3-Kinase α, enhances the effect of selumetinib (AZD6244, ARRY-142886) in KRAS-mutant non-small cell lung cancer

PURPOSE

KRAS is frequently mutated in non-small cell lung cancers (NSCLC), resulting in activation of the MEK/ERK pathway. Because there are currently no drugs that target oncogenic KRAS, MEK inhibitors have been tested clinically as a possible treatment option for patients with NSCLC. However, KRAS-mutant cancers exhibit resistance to MEK inhibitors. Therefore, a combinational strategy is necessary for effective therapy. To address this, we investigated the therapeutic effects of combining selumetinib, a MEK1/2 inhibitor, with BYL719, a PI3Kα inhibitor.

METHODS

We evaluated the effects of selumetinib and BYL719 in vitro and in vivo in NSCLC cell lines.

RESULTS

The combination of BYL719 and selumetinib resulted in synergistic cytotoxic activity compared with the single agents alone in KRAS-mutant NSCLC cells. At the molecular level, we found that AKT activation strongly influenced the sensitivity of KRAS-mutant NSCLC cells to selumetinib. Selumetinib upregulated phospho-AKT and phosphorylated BAD at ser136, which is responsible for intrinsic drug resistance in KRAS-mutant NSCLC cells. In contrast, inhibition of the PI3K/AKT pathway by BYL719 hindered selumetinib-induced BAD phosphorylation and increased the antitumor efficacy of selumetinib. Furthermore, selumetinib and BYL719 combination therapy showed synergy in the suppression of A549 xenograft tumor growth. On analysis of the pharmacodynamics, selumetinib and BYL719 together resulted in effective inhibition of both p-ERK and p-AKT expression in tumor tissue.

CONCLUSION

Taken together, these data suggest that combination treatment with selumetinib and BYL719 is a promising therapeutic approach to overcoming resistance to MEK inhibitors.

COPD-related adenocarcinoma presents low aggressiveness morphological and molecular features compared to smoker tumours

OBJECTIVES

Adenocarcinoma comprises a group of diseases with heterogeneous clinical and molecular characteristics. COPD and lung cancer are strictly related; to date it is unknown if COPD-associated cancers have different features from tumours arising in non-COPD patients. Our aim was to study COPD-associated adenocarcinoma phenotypes mainly focusing on morphological and molecular aspects, in comparison to smoke-related cancer without COPD.

MATERIALS AND METHODS

From 2010 to 2013, 54 patients with adenocarcinoma (20 COPD and 34 smokers) were prospectively studied. Each patient underwent a complete clinical and instrumental assessment. Morphological studies included analysis of growth pattern, cell proliferation (Ki-67/MIB1 expression) and parameters of intra- and peri-tumoral remodelling (inflammation, fibrosis and necrosis). Genetic analysis of EGFR and KRAS mutations was also performed.

RESULTS

The two groups were comparable for the main demographic and biohumoral parameters except for increased blood basophil cell count in the COPD group. Compared to COPD, tumours of smokers presented an increased percentage of solid component (median: 20% vs 5%, p=0.02), a reduced percentage of lepidic pattern (median: 0% vs 10%, p=0.06) and higher Ki-67/MIB1 median value (55% vs 30%, p=0.02). In multivariate analysis lepidic and solid histological pattern were significantly influenced by clinical group (p=0.03 and 0.05, respectively). Concerning EGFR mutation, no differences were found between groups while KRAS mutation presented a trend of higher percentage in smokers compared to COPD (41% vs 20%, p=NS). Adenocarcinoma with KRAS mutation showed a higher value of Ki-67/MIB1 (65% vs 35%, p=0.048) and prevalent solid pattern (35% vs 10%, p=0.019) in comparison to wild-type form.

CONCLUSIONS

COPD-related adenocarcinoma presents molecular and morphological features of lower aggressiveness (increased lepidic component, reduced solid pattern, lower cell proliferation and less frequent KRAS mutation) compared to smokers. Different molecular mechanisms could be associated with the development of COPD associated cancer.

A small molecule that induces reactive oxygen species via cellular glutathione depletion

A new cytotoxic compound was found in our chemical library. We revealed that the compound induced reactive oxygen species through glutathione depletion. Moreover, the compound was effective against several cancer cell lines including those harbouring KRAS.

Associations between mutations and histologic patterns of mucin in lung adenocarcinoma: invasive mucinous pattern and extracellular mucin are associated with KRAS mutation

Multiple reports indicate that epidermal growth factor receptor (EGFR) mutations are associated with lepidic-pattern lung adenocarcinoma and that KRAS mutations are associated with invasive mucinous adenocarcinoma. We sought to investigate the association between EGFR and KRAS mutations and specific morphologic characteristics, such as predominant histologic subtype and mucinous features. Clinical data for 864 patients with resected lung adenocarcinoma that underwent molecular testing for EGFR and KRAS mutations were collected. Histologic subtyping was performed according to the IASLC/ATS/ERS lung adenocarcinoma classification, with attention given to signet-ring cell feature and extracellular mucin. EGFR mutations were detected using a polymerase chain reaction-based sizing assay, KRAS mutations were detected using Sanger sequencing, and ALK expression was detected using immunohistochemistry. Invasive mucinous adenocarcinoma was associated with KRAS mutation (P<0.001). Among invasive mucinous adenocarcinomas with KRAS mutation, a pure mucinous pattern was more common than a mixed mucinous/nonmucinous pattern (P=0.002). Invasive mucinous adenocarcinoma was associated with KRAS transition mutations (G→A) but not transversion mutations (G→T or G→C) compared with nonmucinous tumors (P=0.009). The lepidic-predominant group was associated with EGFR mutation compared with nonlepidic-predominant tumors (P=0.011). Extracellular mucin was associated with KRAS mutation (P<0.001), whereas signet-ring cell feature was not associated with EGFR or KRAS mutation (P=0.517). ALK expression was associated with signet-ring cell feature (P=0.001) but not with extracellular mucin (P=0.089). Our study shows that histologic patterns of mucin in lung adenocarcinoma-including invasive mucinous adenocarcinoma and extracellular mucin-are associated with KRAS mutation.

Prognostic value of epidermal growth factor receptor mutations in resected non-small cell lung cancer: a systematic review with meta-analysis

BACKGROUND

The prognostic value of epidermal growth factor receptor (EGFR) mutations in resected non-small cell lung cancer (NSCLC) remains controversial. We performed a systematic review with meta-analysis to assess its role.

METHODS

Studies were identified via an electronic search on PubMed, Embase and Cochrane Library databases. Pooled hazard ratio (HR) for disease-free survival (DFS) and overall survival (OS) were calculated for meta-analysis.

RESULTS

There were 16 evaluated studies (n  =  3337) in the meta-analysis. The combined HR evaluating EGFR mutations on disease free survival was 0.96 (95% CI [0.79-1.16] P  =  0.65). The combined HR evaluating EGFR mutations on overall survival was 0.86 (95% CI [0.72-1.04] P  = 0.12). The subgroup analysis based on univariate and multivariate analyses in DFS and OS showed no statistically significant difference. There was also no statistically significant difference in DFS and OS of stage I NSCLC patients.

CONCLUSION

The systematic review with meta-analysis showed that EGFR mutations were not a prognostic factor in patients with surgically resected non-small cell lung cancer. Well designed prospective study is needed to confirm the result.

Biomarkers That Currently Affect Clinical Practice in Lung Cancer: EGFR, ALK, MET, ROS-1, and KRAS

Lung cancer remains the most lethal malignancy in the world. Despite improvements in surgical treatment, systemic therapy, and radiotherapy, the 5-year survival rate for all patients diagnosed with lung cancer remains between 15 and 20%. Newer therapeutic strategies rely on specific molecular alterations, or biomarkers, that provide opportunities for a personalized approach to specific patient populations. Classification of lung cancer is becoming increasingly focused on these biomarkers, which renders the term "non-small cell lung" cancer less clinically useful. Non-small cell lung cancer is now recognized as a complex malignancy and its molecular and genomic diversity allows for patient-centered treatment options. Here, we review advances in targeted treatment of lung adenocarcinoma with respect to five clinically relevant biomarkers - EGFR, ALK, MET, ROS-1, and KRAS.

Non-small-cell lung cancers: a heterogeneous set of diseases

Non-small-cell lung cancers (NSCLCs), the most common lung cancers, are known to have diverse pathological features. During the past decade, in-depth analyses of lung cancer genomes and signalling pathways have further defined NSCLCs as a group of distinct diseases with genetic and cellular heterogeneity. Consequently, an impressive list of potential therapeutic targets was unveiled, drastically altering the clinical evaluation and treatment of patients. Many targeted therapies have been developed with compelling clinical proofs of concept; however, treatment responses are typically short-lived. Further studies of the tumour microenvironment have uncovered new possible avenues to control this deadly disease, including immunotherapy.

Non-small-cell lung cancers: a heterogeneous set of diseases

Non-small-cell lung cancers (NSCLCs), the most common lung cancers, are known to have diverse pathological features. During the past decade, in-depth analyses of lung cancer genomes and signalling pathways have further defined NSCLCs as a group of distinct diseases with genetic and cellular heterogeneity. Consequently, an impressive list of potential therapeutic targets was unveiled, drastically altering the clinical evaluation and treatment of patients. Many targeted therapies have been developed with compelling clinical proofs of concept; however, treatment responses are typically short-lived. Further studies of the tumour microenvironment have uncovered new possible avenues to control this deadly disease, including immunotherapy.

EGFR immunoexpression, RAS immunoexpression and their effects on survival in lung adenocarcinoma cases

BACKGROUND

The impacts of epidermal growth factor receptor (EGFR) immunoexpression and RAS immunoexpression on the survival and prognosis of lung adenocarcinoma patients are debated in the literature.

METHODS

Twenty-six patients, who underwent pulmonary resections between 2002 and 2007 in our clinic, and whose pathologic examinations yielded adenocarcinoma, were included in the study. EGFR and RAS expression levels were examined by immunohistochemical methods. The results were compared with the survival, stage of the disease, nodal involvement, lymphovascular invasion, and pleural invasion. Nonparametric bivariate analyses were used for statistical analyses.

RESULTS

A significant link between EGFR immunoexpression and survival has been identified while RAS immunoexpression and survival have been proven to be irrelevant. Neither EGFR, nor RAS has displayed a significant link with the stage of the disease, nodal involvement, lymphovascular invasion, or pleural invasion.

CONCLUSIONS

Positive EGFR immunoexpression affects survival negatively, while RAS immunoexpression has no effect on survival in lung adenocarcinoma patients.

Phase II study of the GI-4000 KRAS vaccine after curative therapy in patients with stage I-III lung adenocarcinoma harboring a KRAS G12C, G12D, or G12V mutation

INTRODUCTION

Patients with early-stage lung cancer have a high risk of recurrence despite multimodality therapy. KRAS-mutant lung adenocarcinomas are the largest genetically defined subgroup, representing 25% of patients. GI-4000 is a heat-killed recombinant Saccharomyces cerevisiae yeast-derived vaccine expressing mutant KRAS proteins. The present phase II study assessed the feasibility, immunogenicity, and safety of the GI-4000 vaccine in patients with early-stage, KRAS-mutant lung cancer.

MATERIALS AND METHODS

Patients with stage I-III KRAS-mutant lung cancer who completed curative therapy were enrolled. The patients received the genotype matched GI-4000 vaccine for ≤ 3 years or until intolerance, disease recurrence, or death. The KRAS antigen T-cell response was assessed using the interferon-gamma enzyme-linked immunospot assay in peripheral blood mononuclear cells. The study was powered to detect an immune response in ≥ 25% of patients.

RESULTS

A total of 24 patients were enrolled over 28 months. No vaccine-related serious adverse events occurred. One patient withdrew consent because of pain at the injection site. The study met its primary endpoint, with 50% of patients developing an immune response to mutant KRAS. The median number of vaccinations received was 15 (range, 1-19). Ten patients experienced disease recurrence, and 6 died. Compared with the genotypically matched historical controls, the recurrence rates were equivalent but overall survival showed a favorable trend.

CONCLUSION

GI-4000 was well tolerated and immunogenic when used as consolidation therapy in patients with stage I-III KRAS-mutant lung cancer. The patterns of recurrence and death observed in the present study can be used to design a randomized study of GI-4000 with overall survival as the primary endpoint.

Clinicopathological characteristics and prognostic impact of colorectal cancers with NRAS mutations

At present, molecular markers of colorectal cancer (CRC), including KRAS, NRAS and BRAF mutations, and the microsatellite status are evaluated for the development of personalized treatments. However, clinicopathological and molecular characteristics and the prognostic role of NRAS mutations remain unclear. In the present study, a total of 1,304 consecutive stage 0-IV CRC tumor samples were analyzed for KRAS (exon 2, 3 and 4), NRAS (exon 2 and 3) and BRAF (exon 15) mutations. Multivariate analysis was performed to assess the prognostic impact of NRAS mutations. KRAS, NRAS and BRAF mutations were identified in 553 (42.4%), 35 (2.7%), and 59 (4.5%) of 1,304 CRC cases, respectively. Tumors with NRAS mutations were more frequently located in the distal colorectum compared with those with KRAS or BRAF mutations. Multivariate analysis indicated that KRAS and BRAF mutations were found to be associated with poor prognosis [hazard ratio (HR)=1.44, 95% confidence interval (CI), 1.18-1.76 and HR=2.09; 95% CI, 1.33-3.28, respectively], whereas NRAS mutations were associated with a trend toward favorable prognosis (HR=0.53; 95% CI, 0.27-1.03). Characteristics and prognosis of CRC with NRAS mutations are different from those with KRAS or BRAF mutations.

KRAS Mutation Detection in Non-small Cell Lung Cancer Using a Peptide Nucleic Acid-Mediated Polymerase Chain Reaction Clamping Method and Comparative Validation with Next-Generation Sequencing

Background

KRAS is one of commonly mutated genetic "drivers" in non-small cell lung cancers (NSCLCs). Recent studies indicate that patients with KRAS-mutated tumors do not benefit from adjuvant chemotherapy, so there is now a focus on targeting KRAS-mutated NSCLCs. A feasible mutation detection method is required in order to accurately test for KRAS status.

Methods

We compared direct Sanger sequencing and the peptide nucleic acid (PNA)-mediated polymerase chain reaction (PCR) clamping method in 134 NSCLCs and explored associations with clinicopathological factors. Next-generation sequencing (NGS) was used to validate the results of discordant cases. To increase the resolution of low-level somatic mutant molecules, PNA-mediated PCR clamping was used for mutant enrichment prior to NGS.

Results

Twenty-one (15.7%) cases were found to have the KRAS mutations using direct sequencing, with two additional cases by the PNA-mediated PCR clamping method. The frequencies of KRAS mutant alleles were 2% and 4%, respectively, using conventional NGS, increasing up to 90% and 89%, using mutant-enriched NGS. The KRAS mutation occurs more frequently in the tumors of smokers (p=.012) and in stage IV tumors (p=.032).

Conclusions

Direct sequencing can accurately detect mutations, but, it is not always possible to obtain a tumor sample with sufficient volume. The PNA-mediated PCR clamping can rapidly provide results with sufficient sensitivity.

Molecular pathways and therapeutic targets in lung cancer

Lung cancer is still the leading cause of cancer death worldwide. Both histologically and molecularly lung cancer is heterogeneous. This review summarizes the current knowledge of the pathways involved in the various types of lung cancer with an emphasis on the clinical implications of the increasing number of actionable molecular targets. It describes the major pathways and molecular alterations implicated in the development and progression of non-small cell lung cancer (adenocarcinoma and squamous cancer), and of small cell carcinoma, emphasizing the molecular alterations comprising the specific blueprints in each group. The approved and investigational targeted therapies as well as the immune therapies, and clinical trials exploring the variety of targeted approaches to treatment of lung cancer are the main focus of this review.

Season of diagnosis and survival of advanced lung cancer cases--any correlation?

INTRODUCTION

The influence of season at diagnosis on cancer survival has been an intriguing issue for many years. Most studies have shown a possible correlation in between the seasonality and some cancer type survival. With short expected survival, lung cancer is an arena that still is in need of new prognostic factors and models. We aimed to investigate the effect of season of diagnosis on 3 months, 1 and 2 years survival rates and overall survival of non small cell lung cancer patients.

MATERIALS AND METHODS

The files of non small cell lung cancer patients that were stages IIIB and IV at diagnosis were reviewed retrospectively. According to diagnosis date, the patients were grouped into 4 season groups, autumn, winter, spring and summer.

RESULTS

A total of 279 advanced non small cell lung cancer patients' files were reviewed. Median overall survival was 15 months in the entire population. Overall 3 months, 1 and 2 years survival rates were 91.0%, 58.2% and 31.2% respectively. The season of diagnosis was significantly correlated with 3 months survival rates, being diagnosed in spring being associated with better survival . Also the season was significantly correlated with T stage of the disease. For 1 and 2 years survival rates and overall survival, the season of diagnosis was not significantly correlated. There was no correlation detected between season and overall survivals according to histological subtypes of non small cell lung cancer.

CONCLUSION

As a new finding in advanced non small cell lung cancer patients, it can be concluded that being diagnosed in spring can be a favorable prognostic factor for short term survival.

ERβ regulates NSCLC phenotypes by controlling oncogenic RAS signaling

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related deaths worldwide. In addition to the aberrant growth factor signaling, dysregulation of other pathways, such as those mediated by estrogens and their receptors, has been linked to NSCLC initiation and progression. Although the expression of wild-type estrogen receptor β (ERβ1) has been associated with prolonged disease-free survival in patients with NSCLC, the molecular mechanism that accounts for this correlation is unknown. Here, upregulation of ERβ1 reduced proliferation and enhanced apoptosis in the context of mutant RAS. ERβ1 was found to induce apoptosis by stimulating the intrinsic apoptotic pathway that involves BIM, a Bcl-2 proapoptotic family member that is regulated by the extracellular signal-regulated kinase (ERK). Downregulation of EGFR and inactivation of RAS and the downstream components ERK1/2 were found to be involved in the ERβ1-induced apoptosis. Manipulation of EGFR and RAS expression and activity in ERβ1-expressing cells revealed the central role of oncogenic RAS inhibition in the ERβ1-mediated proapoptotic phenotype and EGFR regulation. These results demonstrate that ERβ1 decreases the survival of NSCLC cells by regulating oncogenic RAS signaling.

IMPLICATIONS

The ability of ERβ1 to regulate the oncogenic functions of RAS suggests its importance in the biology of NSCLC and its clinical management. Mol Cancer Res; 12(6); 843-54. ©2014 AACR.

KRAS mutations in advanced nonsquamous non-small-cell lung cancer patients treated with first-line platinum-based chemotherapy have no predictive value

BACKGROUND

Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation is thought to be related with dismal outcome for non-small-cell lung cancer (NSCLC) patients. The role of KRAS mutation as a predictor of response to chemotherapy for patients with metastatic NSCLC is poorly understood.

METHODS

From a retrospective database of two university hospitals, all patients with advanced, nonsquamous NSCLC treated with first-line platinum-containing chemotherapy were selected. Mutation analysis for KRAS was performed and the relation with response to chemotherapy was assessed. Secondary endpoints were its relation with response to progression-free survival (PFS) and overall survival (OS).

RESULTS

A total of 161 patients, 94 men and 67 women, were included in this study. Median age was 60 years. The majority of patients (79%) had stage IV disease, of which 60 patients (37%) had a KRAS mutation. Patients with a KRAS mutation had a similar response to treatment as patients with KRAS wild-type (wt) (p = 0.77). Median PFS in KRAS-mutated patients was 4.0 months versus 4.5 months in KRAS wt patients (hazard ratio = 1.3; [95% confidence interval, 0.9-1.8]; p = 0.16). Median OS in patients with KRAS mutation was 7.0 months versus 9.3 months in patients with KRAS wt (hazard ratio = 1.2; [95% confidence interval, 0.9-1.7]; p = 0.25). Type of KRAS mutation had no influence on response or outcome.

CONCLUSION

On the basis of our multicenter data presented here, we conclude that KRAS mutation is not predictive for worse response to chemotherapy, PFS, and OS in advanced NSCLC patients treated with platinum-based chemotherapy in first-line setting.

Clinicopathological and prognostic significance of interleukin-8 expression and its relationship to KRAS mutation in lung adenocarcinoma

Background:

On the basis of our recent findings of oncogenic KRAS-induced interleukin-8 (IL-8) overexpression in non-small cell lung cancer, we assessed the clinicopathological and prognostic significances of IL-8 expression and its relationship to KRAS mutations in lung adenocarcinomas.

Methods:

IL-8 expression was examined by quantitative RT–PCR using 136 of surgical specimens from lung adenocarcinoma patients. The association between IL-8 expression, clinicopathological features, KRAS or EGFR mutation status and survival was analysed.

Results:

IL-8 was highly expressed in tumours from elderly patients or smokers and in tumours with pleural involvement or vascular invasion. In a non-smokers' subgroup, IL-8 level positively correlated with age. IL-8 was highly expressed in tumours with KRAS mutations compared with those with EGFR mutations or wild-type EGFR/KRAS. Lung adenocarcinoma patients with high IL-8 showed significantly shorter disease-free survival (DFS) and overall survival (OS) than those with low IL8. DFS and OS were significantly shorter in the patients with mutant KRAS/high IL-8 than in those with wild-type KRAS/low IL-8. Cox regression analyses demonstrated that elevated IL-8 expression correlated with unfavourable prognosis.

Conclusions:

Our findings suggest that IL-8 expression is associated with certain clinicopathological features including age and is a potent prognostic marker in lung adenocarcinoma, especially in oncogenic KRAS-driven adenocarcinoma.

Alterations of INPP4B, PIK3CA and pAkt of the PI3K pathway are associated with squamous cell carcinoma of the lung

The aim of the study was to investigate how alterations in the PI3K pathway correlate with non-small cell lung cancer subtypes squamous cell carcinoma (SSC) and adenocarcinoma (ADCA). We analyzed copy number variation and protein expression of INPP4B, protein expression of pAkt, PDPK1, and PTEN and mutational status of PIK3CA and PTEN in 180 cases. Nineteen% displayed loss of INPP4B copy, whereas 47% lacked expression, both showing correlation with SCC. Elevated pAkt expression was seen in 63% of all cases, also correlating to SCC. PDPK1 was expressed in 70%, more in male than female patients. Regarding PTEN, 50% displayed loss of expression, of which seven were identified with mutations in the phosphatase domain. We detected nine cases (5%) of PIK3CA mutations, all identified as the E545K hot spot mutation in the helical domain, all except one in SCC. When analyzing all PI3K pathway components together, we show that patients with at least one alteration in the PI3K pathway are twice as likely to have SCC, than ADCA. Interestingly, we also found a strong correlation between high pAkt expression and PTEN expression. As comparison, we also analyzed mitogen-activated protein kinase (MAPK) pathway genes, where we identified fifteen KRAS mutations (8%) and one BRAF mutation (1%), significantly associated to ADCA. No association was found to the Gly972Arg polymorphism of IRS-1, involved in activation of both PI3K and MAPK pathways. In conclusion, we show here that several components of the PI3K pathway, alone and in combination, are correlated to development of SCC of the lung.

Predictive and prognostic biomarkers with therapeutic targets in breast, colorectal, and non-small cell lung cancers: a systemic review of current development, evidence, and recommendation

Appropriate evidence-based roles of prognostic and predictive biomarkers of known therapeutic targets in breast, colorectal, and non-small cell lung cancers in adults are reviewed, with summary of evidence for use and recommendation. Current development in biomarker studies is also discussed. Computerized literature searches of PubMed (National Library of Medicine), the Cochrane Collaboration Library, and commonly accepted US and international guidelines (American Society of Clinical Oncology, European Society for Medical Oncology, and National Comprehensive Cancer Network) were performed from 2001 to 2012. Literature published before 2001 was noted for historical interest but not evaluated. Literature review was focused on available systematic reviews and meta-analyses of published predictive (associated with treatment response and/or efficacy) and prognostic (associated with disease outcome) biomarkers of known therapeutic targets in colorectal, breast, and non-small cell lung cancers. In general, significant health outcomes (e.g. predicted response to therapy, overall survival, disease-free survival, quality of life, lesser toxicity, and cost-effectiveness) were used for making recommendations. Four breast cancer biomarkers were evaluated, two of which (2D6 genotyping, Oncotype Dx) were considered emerging with insufficient evidence. Seven colorectal cancer biomarkers were evaluated, five of which (EGFR gene expression, K-ras G13D gene mutation, B-raf V600E gene mutation, dihydropyrimidine dehydrogenase deficiency, and UGT1A1 genotyping) were considered emerging. Seven non-small cell lung cancer biomarkers were evaluated, five of which were emerging (EGFR gene expression, ERCC gene expression, RRM1 gene expression, K-ras gene mutation, and TS gene expression). Of all 18 biomarkers evaluated, the following showed evidence of clinical utility and were recommended for routine use in practice: ER/PR and HER2 for breast cancer; K-ras gene mutation (except G13D gene mutation) for colorectal cancer; mismatch repair deficiency or microsatellite instability for colorectal cancer; and EGFR and EML4-ALK gene mutations for non-small cell lung. Not all recommendations for these biomarkers were uniformly supported by all guidelines.

Molecular testing in oncology: problems, pitfalls and progress

Recent advances in the understanding of the molecular basis of cancer and the development of molecular diagnostics based on this knowledge have done much to progress the fields of oncology and pathology. Technological developments such as Next Generation Sequencing (NGS) and multiplex assays have made feasible the widespread adoption of molecular diagnostics for clinical use. While these developments and advances carry much promise, there are pitfalls to implementing this testing. Choosing appropriate biomarkers is a vital first step for clinical use and being able to understand the complex relationship between predictive and prognostic biomarkers is a crucial component of this. Testing for standard of care biomarkers is not straightforward, one must choose carefully between clinical trial assays, assays that analyse the same biological phenomenon or surrogate biomarkers. Sample heterogeneity and population specific difference is assays may skew results and must be controlled for at the assay design stage. At a technical level, NGS has the potential to revolutionise laboratory practice and approaches to cancer treatment. However, use of this technology requires careful planning and implementation if one is to avoid technical and ethical quagmires. Finally, with FDA regulation of companion diagnostics one may be limited to therapy specific assays.