Analysis of potential predictive markers of cetuximab benefit in BMS099, a phase III study of cetuximab and first-line taxane/carboplatin in advanced non-small-cell lung cancer

Cutting-Edge Therapies for Lung Cancer

Lung cancer remains a formidable global health challenge that necessitates inventive strategies to improve its therapeutic outcomes. The conventional treatments, including surgery, chemotherapy, and radiation, have demonstrated limitations in achieving sustained responses. Therefore, exploring novel approaches encompasses a range of interventions that show promise in enhancing the outcomes for patients with advanced or refractory cases of lung cancer. These groundbreaking interventions can potentially overcome cancer resistance and offer personalized solutions. Despite the rapid evolution of emerging lung cancer therapies, persistent challenges such as resistance, toxicity, and patient selection underscore the need for continued development. Consequently, the landscape of lung cancer therapy is transforming with the introduction of precision medicine, immunotherapy, and innovative therapeutic modalities. Additionally, a multifaceted approach involving combination therapies integrating targeted agents, immunotherapies, or traditional cytotoxic treatments addresses the heterogeneity of lung cancer while minimizing its adverse effects. This review provides a brief overview of the latest emerging therapies that are reshaping the landscape of lung cancer treatment. As these novel treatments progress through clinical trials are integrated into standard care, the potential for more effective, targeted, and personalized lung cancer therapies comes into focus, instilling renewed hope for patients facing challenging diagnoses.

The role of anti-EGFR therapies in EGFR-TKI-resistant advanced non-small cell lung cancer

Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) are the current recommended option for the first-line treatment of patients with EGFR-mutant non-small cell lung cancer (NSCLC). Resistance to first-generation TKIs led to the development of second- and third-generation TKIs with improved clinical outcomes. However, sequential administration of TKIs has led to the emergence of new EGFR resistance mutations and persistent tumor cell survival. This evidence highlights the potential role of EGFR in transducing growth signals in NSCLC tumor cells. Therefore, dual inhibition of EGFR using combinations of anti-EGFR monoclonal antibodies (mAbs) and EGFR-TKIs may offer a unique treatment strategy to suppress tumor cell growth. Several clinical studies have demonstrated the benefits of dual blockade of EGFR using anti-EGFR mAbs coupled with EGFR-TKIs in overcoming treatment resistance in patients with EGFR-mutated NSCLC. However, a single treatment option may not result in the same clinical benefits in all patients with acquired resistance. Biomarkers, including EGFR overexpression, EGFR gene copy number, EGFR and KRAS mutations, and circulating tumor DNA, have been associated with improved clinical efficacy with anti-EGFR mAbs in patients with NSCLC and acquired resistance. Further investigation of biomarkers may allow patient selection for those who could benefit from anti-EGFR mAbs in combination with EGFR-TKIs. This review summarizes findings of recent studies of anti-EGFR mAbs in combination with EGFR-TKIs for the treatment of patients with EGFR-mutated NSCLC, as well as clinical evidence for potential biomarkers towards personalized targeted medicine.

Recent advances in non-small cell lung cancer targeted therapy; an update review

Lung cancer continues to be the leading cause of cancer-related death worldwide. In the last decade, significant advancements in the diagnosis and treatment of lung cancer, particularly NSCLC, have been achieved with the help of molecular translational research. Among the hopeful breakthroughs in therapeutic approaches, advances in targeted therapy have brought the most successful outcomes in NSCLC treatment. In targeted therapy, antagonists target the specific genes, proteins, or the microenvironment of tumors supporting cancer growth and survival. Indeed, cancer can be managed by blocking the target genes related to tumor cell progression without causing noticeable damage to normal cells. Currently, efforts have been focused on improving the targeted therapy aspects regarding the encouraging outcomes in cancer treatment and the quality of life of patients. Treatment with targeted therapy for NSCLC is changing rapidly due to the pace of scientific research. Accordingly, this updated study aimed to discuss the tumor target antigens comprehensively and targeted therapy-related agents in NSCLC. The current study also summarized the available clinical trial studies for NSCLC patients.

Efficacy and safety of EGFR inhibitors and radiotherapy in locally advanced non-small-cell lung cancer: a meta-analysis

Aim: To assess the efficacy and safety of EGFR inhibitors combined with (chemo)radiotherapy in unresectable, locally advanced non-small-cell lung cancer. Materials & methods: A systematic review and meta-analysis of prospective trials was performed. Results: Twenty-eight studies of 1640 patients were included. In patients harboring EGFR-sensitive mutations, the pooled objective response rate, 1-year overall survival rate and 1-year progression-free survival rate of EGFR-TKIs + (chemo)radiotherapy were 0.803, 0.766 and 0.554, respectively. Compared with chemoradiotherapy, the addition of EGFR inhibitors did not significantly increase the risk of grade ≥3 pneumonitis and esophagitis. Conclusion: EGFR-tyrosine kinase inhibitors combined with (chemo)radiotherapy are tolerable and the clinical benefit is promising, especially in patients with EGFR-sensitive mutations.

Potential of Farnesyl Transferase Inhibitors in Combination Regimens in Squamous Cell Carcinomas

Current therapies for recurrent and metastatic SCC are associated with poor outcomes, and options for later lines of treatment are limited. Insights into potential therapeutic targets, as well as mechanisms of resistance to available therapies, have begun to be elucidated, creating the basis for exploration of combination approaches to drive better patient outcomes. Tipifarnib, a farnesyl transferase inhibitor (FTI), is a small molecule drug that has demonstrated encouraging clinical activity in a genetically-defined subset of head and neck squamous cell carcinoma (HNSCC)-specifically, tumors that express a mutation in the HRAS protooncogene. More recently, bioinformatic analyses and results from patient-derived xenograft modeling indicate that HRAS pathway dependency may extend to a broader subpopulation of SCCs beyond HRAS mutants in the context of combination with agents such as cisplatin, cetuximab, or alpelisib. In addition, tipifarnib can also inactivate additional farnesylated proteins implicated in resistance to approved therapies, including immunotherapies, through a variety of distinct mechanisms, suggesting that tipifarnib could serve as an anchor for combination regimens in SCCs and other tumor types.

Current therapy of KRAS-mutant lung cancer

KRAS mutations are the most frequent gain-of-function alterations in patients with lung adenocarcinoma (LADC) in the Western world. Although they have been identified decades ago, prior efforts to target KRAS signaling with single-agent therapeutic approaches such as farnesyl transferase inhibitors, prenylation inhibition, impairment of KRAS downstream signaling, and synthetic lethality screens have been unsuccessful. Moreover, the role of KRAS oncogene in LADC is still not fully understood, and its prognostic and predictive impact with regards to the standard of care therapy remains controversial. Of note, KRAS-related studies that included general non-small cell lung cancer (NSCLC) population instead of LADC patients should be very carefully evaluated. Recently, however, comprehensive genomic profiling and wide-spectrum analysis of other co-occurring genetic alterations have identified unique therapeutic vulnerabilities. Novel targeted agents such as the covalent KRAS G12C inhibitors or the recently proposed combinatory approaches are some examples which may allow a tailored treatment for LADC patients harboring KRAS mutations. This review summarizes the current knowledge about the therapeutic approaches of KRAS-mutated LADC and provides an update on the most recent advances in KRAS-targeted anti-cancer strategies, with a focus on potential clinical implications.

Efficacy and Safety of EGFR Inhibitors in the Treatment of EGFRPositive NSCLC Patients: A Meta-Analysis

BACKGROUND

We compared the response rates, survival rates, and safety profile of epidermal growth factor receptor (EGFR) inhibitors with non-targeted chemotherapy and older EGFR inhibitors when used to treat advanced non-small cell lung cancer (NSCLC) patients with activating EGFR mutations.

METHODS

We searched PubMed, Cochrane Central Register of Controlled Trials, and clinicaltrial.- gov for randomized controlled trials published until 11-Feb-2020. Treatment outcomes were compared between EGFR inhibitor and pooled comparator; a subgroup analysis compared outcomes between EGFR inhibitor and non-targeted chemotherapy, and between newer and older EGFR inhibitors.

RESULTS

Twenty-one studies with 4,250 unique patients were included. Significantly higher objective response rate (ORR) (odds ratio (OR) 2.28; 95% CI 2.00-2.61), higher disease control rate (DCR) (OR 2.3; 95% CI 1.88-3.06), and longer progression-free survival (PFS) (Hazard ratio (HR) 0.56; 95% CI 0.52-0.60) were observed in the EGFR inhibitor group compared to the pooled comparator group. Subgroup analysis revealed that the ORR, DCR, and PFS were significantly higher with EGFR inhibitors than non-targeted chemotherapy, and only PFS (and not ORR and DCR) was significantly longer with newer EGFR inhibitors than the older EGFR inhibitors. Overall survival (OS) was not significantly different between EGFR inhibitors and pooled comparator (HR 0.91; 95% CI 0.83-1.00) as well as in either of the subgroup analyses. Adverse events ≥ grade 3 and treatment discontinuation were significantly higher with non-targeted chemotherapy compared to the EGFR inhibitors.

CONCLUSION

The benefits of prolongation of ORR, DCR, and PFS might not imply significantly improved OS after therapy with EGFR inhibitors when compared with non-targeted chemotherapy or older EGFR inhibitors.

First-line treatment of advanced epidermal growth factor receptor (EGFR) mutation positive non-squamous non-small cell lung cancer

BACKGROUND

Epidermal growth factor receptor (EGFR) mutation positive (M+) non-small cell lung cancer (NSCLC) is an important subtype of lung cancer comprising 10% to 15% of non-squamous tumours. This subtype is more common in women than men, is less associated with smoking, but occurs at a younger age than sporadic tumours.

OBJECTIVES

To assess the clinical effectiveness of single-agent or combination EGFR therapies used in the first-line treatment of people with locally advanced or metastatic EGFR M+ NSCLC compared with other cytotoxic chemotherapy (CTX) agents used alone or in combination, or best supportive care (BSC). The primary outcomes were overall survival and progression-free survival. Secondary outcomes included response rate, symptom palliation, toxicity, and health-related quality of life.

SEARCH METHODS

We conducted electronic searches of the Cochrane Register of Controlled Trials (CENTRAL) (2020, Issue 7), MEDLINE (1946 to 27th July 2020), Embase (1980 to 27th July 2020), and ISI Web of Science (1899 to 27th July 2020). We also searched the conference abstracts of the American Society for Clinical Oncology and the European Society for Medical Oncology (July 2020); Evidence Review Group submissions to the National Institute for Health and Care Excellence; and the reference lists of retrieved articles.

SELECTION CRITERIA

Parallel-group randomised controlled trials comparing EGFR-targeted agents (alone or in combination with cytotoxic agents or BSC) with cytotoxic chemotherapy (single or doublet) or BSC in chemotherapy-naive patients with locally advanced or metastatic (stage IIIB or IV) EGFR M+ NSCLC unsuitable for treatment with curative intent.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified articles, extracted data, and carried out the 'Risk of bias' assessment. We conducted meta-analyses using a fixed-effect model unless there was substantial heterogeneity, in which case we also performed a random-effects analysis as a sensitivity analysis.

MAIN RESULTS

Twenty-two trials met the inclusion criteria. Ten of these exclusively recruited people with EGFR M+ NSCLC; the remainder recruited a mixed population and reported results for people with EGFR M+ NSCLC as subgroup analyses. The number of participants with EGFR M+ tumours totalled 3023, of whom approximately 2563 were of Asian origin. Overall survival (OS) data showed inconsistent results between the included trials that compared EGFR-targeted treatments against cytotoxic chemotherapy or placebo. Erlotinib was used in eight trials, gefitinib in nine trials, afatinib in two trials, cetuximab in two trials, and icotinib in one trial. The findings of FASTACT 2 suggested a clinical benefit for OS for participants treated with erlotinib plus cytotoxic chemotherapy when compared to cytotoxic chemotherapy alone, as did the Han 2017 trial for gefitinib plus cytotoxic chemotherapy, but both results were based on a small number of participants (n = 97 and 122, respectively). For progression-free survival (PFS), a pooled analysis of four trials showed evidence of clinical benefit for erlotinib compared with cytotoxic chemotherapy (hazard ratio (HR) 0.31; 95% confidence interval (CI) 0.25 to 0.39 ; 583 participants ; high-certainty evidence). A pooled analysis of two trials of gefitinib versus paclitaxel plus carboplatin showed evidence of clinical benefit for PFS for gefitinib (HR 0.39; 95% CI 0.32 to 0.48 ; 491 participants high-certainty evidence), and a pooled analysis of two trials of gefitinib versus pemetrexed plus carboplatin with pemetrexed maintenance also showed evidence of clinical benefit for PFS for gefitinib (HR 0.59; 95% CI 0.46 to 0.74, 371 participants ; moderate-certainty evidence). Afatinib showed evidence of clinical benefit for PFS when compared with chemotherapy in a pooled analysis of two trials (HR 0.42; 95% CI 0.34 to 0.53, 709 participants high-certainty evidence). All but one small trial showed a corresponding improvement in response rate with tyrosine-kinase inhibitor (TKI) compared to chemotherapy. Commonly reported grade 3/4 adverse events associated with afatinib, erlotinib, gefitinib and icotinib monotherapy were rash and diarrhoea. Myelosuppression was consistently worse in the chemotherapy arms; fatigue and anorexia were also associated with some chemotherapies. Seven trials reported on health-related quality of life and symptom improvement using different methodologies. For each of erlotinib, gefitinib, and afatinib, two trials showed improvement in one or more indices for the TKI compared to chemotherapy. The quality of evidence was high for the comparisons of erlotinib and gefitinib with cytotoxic chemotherapy and for the comparison of afatinib with cytotoxic chemotherapy.

AUTHORS' CONCLUSIONS

Erlotinib, gefitinib, afatinib and icotinib are all active agents in EGFR M+ NSCLC patients, and demonstrate an increased tumour response rate and prolonged PFS compared to cytotoxic chemotherapy. We found a beneficial effect of the TKI compared to cytotoxic chemotherapy in adverse effect and health-related quality of life. We found limited evidence for increased OS for the TKI when compared with standard chemotherapy, but the majority of the included trials allowed participants to switch treatments on disease progression, which will have a confounding effect on any OS analysis. Single agent-TKI remains the standard of care and the benefit of combining a TKI and chemotherapy remains uncertain as the evidence is based on small patient numbers. Cytotoxic chemotherapy is less effective in EGFR M+ NSCLC than erlotinib, gefitinib, afatinib or icotinib and is associated with greater toxicity. There are no data supporting the use of monoclonal antibody therapy. Icotinib is not available outside China.

KRAS mutation as a prognostic factor and predictive factor in advanced/metastatic non-small cell lung cancer: A systematic literature review and meta-analysis

KRAS (Kirsten Rat Sarcoma) is the most common oncogenic mutation detected in patients with non-small cell lung cancer (NSCLC). However, the role of KRAS as either a prognostic factor or predictive factor (modifier of treatment effects) in NSCLC is not well established at this time. This systematic literature review (SLR) and meta-analysis synthesized the available evidence regarding the role of KRAS mutation as a predictive factor and/or prognostic factor of survival and response outcomes in patients with advanced/metastatic (stage IIIB-IV) NSCLC. Relevant clinical trials and observational studies were identified by searching MEDLINE, Embase and Cochrane Register of Controlled Trials. Meta-analyses were performed using data extracted from multivariable and univariable analyses from clinical studies to assess the empirical evidence of KRAS mutation status as a prognostic or/and predicitive factor. 43 selected studies were identified by the SLR and included in this meta-analysis. Pairwise meta-analyses of hazard ratios (HRs) reported in randomized controlled trials (RCTs) did not demonstrate a significant prognostic effect of mutant KRAS on overall survival (OS) (HR=1.10; 95% CI [0.88, 1.38]) or progression free survival (PFS) (HR=1.03; 95% CI [0.80, 1.33]). However, when conducting meta-analyses on HRs reported in observational studies, a statistically significant negative prognostic effect of mutant KRAS was observed (OS HR=1.71; 95% CI [1.07, 2.84]; PFS HR=1.18; 95% CI [1.02, 1.36]). Meta-analyses of objective response rate (ORR) in RCTs demonstrated a negative prognostic effect of mutant KRAS (RR=0.38; 95% CI [0.16, 0.63]). Limited data were available to evaluate the role of KRAS mutation as a predictive factor. In conclusion, this research offers evidence that KRAS mutation may be a negative prognostic factor for survival and response outcomes in patients with advanced/metastatic NSCLC, but further research is needed to address conflicting results on the importance of KRAS mutations as a predictive factor.

Observed versus modelled lifetime overall survival of targeted therapies and immunotherapies for advanced non-small cell lung cancer patients - A systematic review

Outcomes used for the effectiveness (median) and cost-effectiveness (mean) on overall survival (OS) are different and can vary from one another. Therefore, we compared median and mean OS gains of targeted therapies and immunotherapies for stage IIIB/IV Non-small cell lung cancer and explored underlying aspect. Eligible trials were searched in PubMed, survival curves were digitized, and parametric survival models fitted to model the mean OS. Twenty-seven trials were found for targeted therapies (n = 17) and immunotherapies (n = 10). Differences between median and mean OS gains in months ranged from -2.8 to 6.8 and -4.9 to 0.3 for two different subgroups of targeted therapies, and -2.4 to 11.4 for immunotherapies. The mean OS gain was substantially larger for most immunotherapy trials, due to relatively long survival. Median and mean OS gains did not differ for targeted therapies. Our findings imply a potential discrepancy between the estimates of effectiveness and cost-effectiveness of cancer treatments.

Predictive biomarkers for response to EGFR-directed monoclonal antibodies for advanced squamous cell lung cancer

Background

Upregulated expression and aberrant activation of the epidermal growth-factor receptor (EGFR) are found in lung cancer, making EGFR a relevant target for non-small-cell lung cancer (NSCLC). Treatment with anti-EGFR monoclonal antibodies (mAbs) is associated with modest improvement in overall survival in patients with squamous cell lung cancer (SqCLC) who have a significant unmet need for effective treatment options. While there is evidence that using EGFR gene copy number, EGFR mutation, and EGFR protein expression as biomarkers can help select patients who respond to treatment, it is important to consider biomarkers for response in patients treated with combination therapies that include EGFR mAbs.

Design

Randomized trials of EGFR-directed mAbs cetuximab and necitumumab in combination with chemotherapy, immunotherapy, or antiangiogenic therapy in patients with advanced NSCLC, including SqCLC, were searched in the literature. Results of associations of potential biomarkers and outcomes were summarized.

Results

Data from phase III clinical trials indicate that patients with NSCLC, including SqCLC, whose tumors express high levels of EGFR protein (H-score of ≥200) and/or gene copy numbers of EGFR (e.g. ≥40% cells with ≥4 EGFR copies as detected by fluorescence in situ hybridization; gene amplification in ≥10% of analyzed cells) derive greater therapeutic benefits from EGFR-directed mAbs. Biomarker data are limited for EGFR mAbs used in combination with immunotherapy and are absent when used in combination with antiangiogenic agents.

Conclusions

Therapy with EGFR-directed mAbs in combination with chemotherapy is associated with greater clinical benefits in patients with NSCLC, including SqCLC, whose tumors express high levels of EGFR protein and/or have increased EGFR gene copy number. These data support validating the role of these as biomarkers to identify those patients who derive the greatest clinical benefit from EGFR mAb therapy. However, data on biomarkers for EGFR-directed mAbs combined with immunotherapy or antiangiogenic agents remain limited.

Targeting Cancer Resistance via Multifunctional Gold Nanoparticles

Resistance to chemotherapy is a major problem facing current cancer therapy, which is continuously aiming at the development of new compounds that are capable of tackling tumors that developed resistance toward common chemotherapeutic agents, such as doxorubicin (DOX). Alongside the development of new generations of compounds, nanotechnology-based delivery strategies can significantly improve the in vivo drug stability and target specificity for overcoming drug resistance. In this study, multifunctional gold nanoparticles (AuNP) have been used as a nanoplatform for the targeted delivery of an original anticancer agent, a Zn(II) coordination compound [Zn(DION)2]Cl2 (ZnD), toward better efficacy against DOX-resistant colorectal carcinoma cells (HCT116 DR). Selective delivery of the ZnD nanosystem to cancer cells was achieved by active targeting via cetuximab, NanoZnD, which significantly inhibited cell proliferation and triggered the death of resistant tumor cells, thus improving efficacy. In vivo studies in a colorectal DOX-resistant model corroborated the capability of NanoZnD for the selective targeting of cancer cells, leading to a reduction of tumor growth without systemic toxicity. This approach highlights the potential of gold nanoformulations for the targeting of drug-resistant cancer cells.

Immuno-PET imaging for non-invasive assessment of cetuximab accumulation in non-small cell lung cancer

Backgrounds

Overexpression of epidermal growth factor receptor (EGFR) has been established as a valid therapeutic target of non-small cell lung cancer (NSCLC). However, the clinical benefit of cetuximab as an EGFR-targeting drug is still controversial, partially due to the lack of effective means to identify suitable patients. This study aimed to investigate the potential of radiolabeled cetuximab as a non-invasive tool to predict cetuximab accumulation in NSCLC tumor xenografts with varying EGFR expression levels.

Methods

The NSCLC tumors in model mice were subjected to in vivo biodistribution study and positron emission tomography (PET) imaging 48 h after injection of either ¹¹¹In- or ⁶⁴Cu-labeled cetuximab. The EGFR expression levels of NSCLC tumors were determined by ex vivo immunoblotting.

Results

We found that tumors with high EGFR expression had significantly higher [¹¹¹In]In-DOTA-cetuximab accumulation than tumors with moderate to low EGFR expression (P < 0.05). Strong correlations were found between [¹¹¹In]In-DOTA-cetuximab tumor uptake and EGFR expression level (r = 0.893), and between [⁶⁴Cu]Cu-DOTA-cetuximab tumor uptake with EGFR expression level (r = 0.915). PET imaging with [⁶⁴Cu]Cu-DOTA-cetuximab allowed clear visualization of tumors.

Conclusion

Our findings suggest that this immuno-PET imaging can be clinically translated as a tool to predict cetuximab accumulation in NSCLC cancer patients prior to cetuximab therapy.

Effect of Cetuximab and EGFR Small Interfering RNA Combination Treatment in NSCLC Cell Lines with Wild Type EGFR and Use of KRAS as a Possible Biomarker for Treatment Responsiveness

Background

The epidermal growth factor receptor (EGFR) is a therapeutic target for patients with non-small cell lung cancer (NSCLC). Cetuximab is an anti-EGFR monoclonal antibody that inhibits EGFR signaling and proliferation of colorectal cancer and head and neck cancers. Since only few NSCLC patients benefit from cetuximab therapy, we evaluated a novel combination treatment using cetuximab and EGFR small interfering RNA (siRNA) to strongly suppress EGFR signaling and searched for a biomarker in NSCLC cell lines harboring wild-type EGFR.

Methods

Alterations in EGFR and its downstream genes in five NSCLC cell lines (A549, Lu99, 86-2, Sq19 and Ma10) were assessed through sequencing. The protein expression levels of these molecules were assessed through western blotting. The effect of combination treatment was determined through cell proliferation assay, caspase-3/7 assay, invasion assay, and migration assay.

Results

All cell lines were harboring wild-type EGFR, whereas KRAS, PTEN, TP53 and TP53 were mutated in A549 and Lu99; Lu99 and Sq19; Lu99, 86-2, Sq19 and Ma10; and A549, 86-2, and Sq19 cell lines, respectively. PTEN was not expressed in Sq19, and LKB1 was not expressed in both A549 and Sq19. TP53 was not expressed in both A549 and Lu99. The combination of cetuximab and EGFR siRNA significantly suppressed cell proliferation in 86-2, Sq19 and Ma10, which express wild-type KRAS. It induced apoptosis in A549, 86-2 and Ma10 cells, which express wild type PTEN. The combination treatment had no effect either on cell invasion nor migration in all cell lines.

Conclusion

EGFR targeted therapy using the combination of cetuximab and EGFR siRNA is effective in NSCLC cell lines harboring wild-type EGFR. Wild-type KRAS may act as a potential biomarker for response to combination treatment by the induction of apoptosis in cells with wild-type PTEN.

Cetuximab for treating non-small cell lung cancer

INTRODUCTION

Epidermal Growth Factor Receptor (EGFR)-dependent signaling plays a crucial role in epithelial cancer biology, and dictated the development of several targeting agents. The mouse-human chimeric antibody Cetuximab was among the first to be developed. After about two decades of clinical research it has gained a significant place in the management of advanced colorectal and head and neck cancers, whereas its development in non small cell lung cancer (NSCLC) has not led to a place in routine clinical practice, because of marginal clinical benefit despite statistically significant Phase III trials. Recent data from ongoing trials suggest that more careful selection based on molecular markers may identify good responders. Areas covered: In this article, the authors review the literature concerning basic science studies identifying EGFR as a therapeutic target, pharmacological development of Cetuximab, its pharmacodynamics and pharmacokinetics, and clinical trials on Cetuximab in NSCLC, focusing on recent findings on putative predictive biomarkers. Expert opinion: Cetuximab currently has no role in NSCLC treatment outside of research settings. We argue that failure to identify a predictive biomarker early on has hampered its chances to enter routine practice. Although recent research suggests benefit in highly selected patient subsets, its potential impact is severely dampened by lack of regulatory body approval and the emergence of competitors for the same niches.

Necitumumab in the treatment of non-small-cell lung cancer: clinical controversies

INTRODUCTION

Over the last decade, epidermal growth factor receptor (EGFR) signaling was investigated as a potential target for tyrosine kinase inhibitors in the treatment of non-small-cell lung cancer (NSCLC). Necitumumab is a fully humanized IgG1 monoclonal antibody directed against the binding domain of EGFR, approved in combination with cisplatin-gemcitabine for the first-line treatment of squamous NSCLC. Areas covered: The purpose of this manuscript is to systematically review the state of the art of necitumumab for the treatment of metastatic NSCLC, focusing on predictive factors, cost-effectiveness, and future potential combinations with additional agents. Expert opinion: Despite recent therapeutic advances, platinum-based chemotherapy still represents the most widely used first-line treatment for advanced NSCLC, particularly for the squamous histotype. Necitumumab is nowadays the first targeted agent providing an (statistically significant) additional survival gain to squamous NSCLC patients when combined with first-line chemotherapy at the cost of an increased (although manageable) toxicity, as shown in the SQUIRE trial. Hopefully, improvement in patients' selection by identifying reliable predictive markers and the combination with new agents may help to maximize the benefit of this targeted treatment, which is currently limited by a not optimal cost-benefit ratio.

EGFR-directed monoclonal antibodies in combination with chemotherapy for treatment of non-small-cell lung cancer: an updated review of clinical trials and new perspectives in biomarkers analysis

Lung cancer still represents one of the most common and fatal neoplasm, accounting for nearly 30% of all cancer-related deaths. Targeted therapies based on molecular tumor features and programmed death-1 (PD-1)/programmed death ligand-1 (PDL-1) blockade immunotherapy have offered new therapeutic options for patients with advanced non-small-cell lung cancer (NSCLC). Activation of the epidermal growth factor receptor (EGFR)-pathway promotes tumor growth and progression, including angiogenesis, invasion, metastasis and inhibition of apoptosis, providing a strong rationale for targeting this pathway. EGFR expression is detected in up to 85% of NSCLC and has been demonstrated to be associated with poor prognosis. Two approaches for blocking EGFR signaling are available: prevention of ligand binding to the extracellular domain with monoclonal antibodies (mAbs) and inhibition of the intracellular tyrosine kinase activity with small molecules. There is a strong rationale to consider the tumor's level of EGFR expression as one of the most significant predictive biomarkers in this setting. In this paper we provide an update focusing on the current status of EGFR-directed mAbs use for the treatment of patients with advanced NSCLC, through a review of all clinical trials involving anti-EGFR mAbs in combination with chemotherapy (CT) for advanced disease and with chemo-radiotherapy for stage III disease. Here we also discuss the current status of predictive biomarkers for anti-EGFR mAbs when added to first-line CT in patients with advanced NSCLC. Finally, we focused on the relevance of EGFR fluorescence in situ hybridization (FISH)+ and immunohistochemistry (IHC)-Score ≥ 200 as predictive biomarkers for the selection of patients who would be most likely to derive a clinical benefit from treatment with CT in combination with anti-EGFR mAbs, with particular reference also to histology.

Diagnostic and prognostic value of blood samples for KRAS mutation identification in lung cancer: a meta-analysis

Circulating tumor DNA (ctDNA) and tumor cells (CTC) are novel approaches for identifying genomic alterations. Thus, we designed a meta-analysis to evaluate the diagnostic value and prognostic significance of a KRAS proto-oncogene, GTPase (KRAS) mutation for lung cancer patients. All included articles were from PubMed, EMBASE, Web of Science and Cochrane Library. Twelve articles that described 1,131 patients were reviewed. True positives (TP), false positives (FP), true negatives (TN), and false negatives (FN) were used to calculate pooled sensitivity, specificity, the positive likelihood ratio (PLR), the negative likelihood ratio (NLR), a diagnostic odds ratio (DOR), the area under the curve (AUC) and corresponding 95% confidence intervals (95% CI). PLR is calculated as sensitivity/(1-specificity) and NLR is (1– sensitivity)/specificity. DOR is a measured of diagnostic effectiveness (PLR/NLR). A survival analysis subgroup was also designed to evaluate prognostic significance. Pooled sensitivity, specificity, PLR, NLR, DOR and AUC were 0.79 (95% CI, 0.63-0.89), 0.93 (95% CI, 0.89-0.96), 12.13 (92% CI, 7.11-20.67), 0.22 (95% CI, 0.12-0.41), 54.82 (95% CI, 23.11-130.09), and 0.95 (95% CI, 0.93–0.96), respectively. KRAS mutation and wild-type hazard ratios for overall survival and progression-free survival were 1.37 (95% CI, 1.08–1.66), 1.46 (95% CI, 1.15-1.77) in blood samples, and 1.16 (95% CI, 1.03–1.28), 1.28 (95% CI, 1.09–1.46) in tumor tissue.

KRAS oncogene in non-small cell lung cancer: clinical perspectives on the treatment of an old target

Lung neoplasms are the leading cause of death by cancer worldwide. Non-small cell lung cancer (NSCLC) constitutes more than 80% of all lung malignancies and the majority of patients present advanced disease at onset. However, in the last decade, multiple oncogenic driver alterations have been discovered and each of them represents a potential therapeutic target. Although KRAS mutations are the most frequently oncogene aberrations in lung adenocarcinoma patients, effective therapies targeting KRAS have yet to be developed. Moreover, the role of KRAS oncogene in NSCLC remains unclear and its predictive and prognostic impact remains controversial. The study of the underlying biology of KRAS in NSCLC patients could help to determine potential candidates to evaluate novel targeted agents and combinations that may allow a tailored treatment for these patients. The aim of this review is to update the current knowledge about KRAS-mutated lung adenocarcinoma, including a historical overview, the biology of the molecular pathways involved, the clinical relevance of KRAS mutations as a prognostic and predictive marker and the potential therapeutic approaches for a personalized treatment of KRAS-mutated NSCLC patients.

Targeting Novel but Less Common Driver Mutations and Chromosomal Translocations in Advanced Non-Small Cell Lung Cancer

Discovery of the epidermal growth factor receptor gene mutation and the anaplastic lymphoma kinase chromosomal translocation in non-small cell lung cancer has prompted efforts around the world to identify many less common targetable oncogenic drivers. Such concerted efforts have been variably successful in both non-squamous and squamous cell carcinomas of the lung. Some of the targeted therapies for these oncogenic drivers have received regulatory approval for clinical use, while others have modest clinical benefit. In this mini-review, several of these targets will be reviewed.

Challenges and future of biomarker tests in the era of precision oncology: Can we rely on immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH) to select the optimal patients for matched therapy?

Molecular techniques have improved our understanding of the pathogenesis of cancer development. These techniques have also fueled the rational development of targeted drugs for patient populations stratified by their genetic characteristics. These novel methods have changed the classic paradigm of diagnostic pathology; among them are IHC, FISH, polymerase chain reaction (PCR) and microarray technology. IHC and FISH detection methods for human epidermal growth factor receptor-2 (HER2), epidermal growth factor receptor (EGFR) and programmed death ligand-1 (PD-L1) were recently approved by the Food and Drug Administration (FDA) as routine clinical practice for cancer patients. Here, we discuss general challenges related to the predictive power of these molecular biomarkers for targeted therapy in cancer medicine. We will also discuss the prospects of utilizing new biomarkers for fibroblast growth factor receptor (FGFR) and hepatocyte growth factor receptor (cMET/MET) targeted therapies for developing new and robust predictive biomarkers in oncology.

First-Line Carboplatin, Pemetrexed, and Panitumumab in Patients with Advanced Non-Squamous KRAS Wild Type (WT) Non-Small-Cell Lung Cancer (NSCLC)

BACKGROUND

We added panitumumab to standard combination chemotherapy as first-line treatment for patients with advanced KRAS WT non-squamous NSCLC.

METHODS

Patients received panitumumab 9 mg/kg IV, pemetrexed 500 mg/m² IV, and carboplatin AUC = 6 IV every 21 days. After 6 cycles, maintenance therapy with panitumumab and pemetrexed was administered every 21 days until progressive disease or unacceptable toxicity.

RESULTS

29 of 66 patients (44%) had objective responses. The median TTP was 6 months; median overall survival (OS) was 17 months. Panitumumab increased treatment-related toxicity, notably skin rash.

CONCLUSIONS

The addition of panitumumab increased toxicity, and had no discernible impact on efficacy.

The role of PRMT1 in EGFR methylation and signaling in MDA-MB-468 triple-negative breast cancer cells

BACKGROUND

Epidermal growth factor receptor (EGFR) is often overexpressed in triple-negative breast cancer (TNBC). However, clinical studies have shown that therapies against EGFR are not effective in patients with TNBC. Recently, it has been reported that arginine 198/200 in EGFR extracellular domain is methylated by PRMT1 and that the methylation confers resistance to EGFR monoclonal antibody cetuximab in colorectal cancer cells. To explore a potential mechanism underlying intrinsic resistance to anti-EGFR therapy in TNBC, we investigated the role of PRMT1 in EGFR methylation and signaling in MDA-MB-468 (468) TNBC cells.

METHODS

We knocked down PRMT1 in 468 cells by shRNA, and subjected the cell lysates to Western blot analysis to examine EGFR activation and its downstream molecules. We also evaluated cell proliferation and sphere formation of PRMT1-knockdown cells. Finally, we examined the effects of pan-PRMT inhibitor, AMI-1, on cetuximab by colony formation and soft agar assays.

RESULTS

EGFR methylation and activity was significantly reduced in PRMT1-knockdown cells compared to the parental cells. Knockdown of PRMT1 also reduced cell proliferation and sphere formation. Moreover, AMI-1 sensitized 468 cells to cetuximab.

CONCLUSION

The results indicate that PRMT1 is critical for EGFR activity in 468 cells. Our data also suggest that inhibition of PRMT1 sensitizes TNBC cells to cetuximab. Thus, inhibition of PRMT1 may be an effective therapeutic strategy to overcome intrinsic resistance to cetuximab in TNBC.

First-Line Systemic Therapy for Non-Small Cell Lung Cancer

Major advances in the treatment of metastatic non-small cell lung cancer have led to significant incremental improvements in patient outcomes. Platinum-based combination therapy remains the cornerstone of first-line therapy. The addition of biologic agents, such as bevacizumab or necitumumab, in selected populations has shown benefit over chemotherapy alone. The advent of maintenance therapy has also improved overall survival outcomes in selected populations of patients. Ongoing studies will further refine optimal treatment in the first-line setting and further advance first-line treatment options.

Synthesis and biochemical characterization of EGF receptor in a water-soluble membrane model system

ErbB (Erythroblastic Leukemia Viral Oncogene Homolog) receptor tyrosine kinases are critical for tissue development and maintenance, and frequently become oncogenic when mutated or overexpressed. In vitro analysis of ErbB receptor kinases can be difficult because of their large size and poor water solubility. Here we report improved production and assembly of the correctly folded full-length EGF receptor (EGFR) into nanolipoprotein particles (NLPs). NLPs are ~10 nm in diameter discoidal cell membrane mimics composed of apolipoproteins surrounding a lipid bilayer. NLPs containing EGFR were synthesized via incubation of baculovirus-produced recombinant EGFR with apolipoprotein and phosphoplipids under conditions that favor self-assembly. The resulting EGFR-NLPs were the correct size, formed dimers and multimers, had intrinsic autophosphorylation activity, and retained the ability to interact with EGFR-targeted ligands and inhibitors consistent with previously-published in vitro binding affinities. We anticipate rapid adoption of EGFR-NLPs for structural studies of full-length receptors and drug screening, as well as for the in vitro characterization of ErbB heterodimers and disease-relevant mutants.

Molecular biomarkers for lung adenocarcinoma

The identification of oncogenic driver alterations that underlie sensitivity to small inhibitors has led to growing interest in identifying additional targetable oncogenes in nonsmall cell lung cancer. Although the therapeutic impact of the discovery of these alterations has now been widely demonstrated, the epidemiological data associated with each of these biomarkers remain insufficiently studied. In this review, we discuss the techniques used to discover each of these candidate oncogenes, their prevalence in nonsmall cell lung cancer, and briefly outline the epidemiological features of the major oncogenes and ways in which their identification can determine therapeutic strategies.

Biology and patterns of response to EGFR-inhibition in squamous cell cancers of the lung and head & neck

The identification of common molecular aberrations that drive cancer progression has led to targeted therapies that improve treatment efficacy in many tumor types. Epidermal growth factor receptor (EGFR) inhibitors have been used to treat both lung and head and neck cancers with squamous cell histology. These tumors often show high EGFR expression and/or increased gene copy number, but low incidence of the activating kinase domain mutations common to adenocarcinomas of the lung. In this manuscript, we review clinical trial data on EGFR-inhibitors in the treatment of squamous cell carcinoma (SqCC) of the lung and head and neck (SCCHN), including both efficacy and biomarker analyses. Although some efficacy with use of EGFR inhibitors is observed, the level of benefit varies within and across tumor types, and the predictive capacity of high EGFR protein expression and/or gene amplification, if any, is limited. Due to the lack of candidate biomarkers that consistently predict response to EGFR-inhibitor therapy across treatment setting and class of agent in SqCC of the lung and SCCHN, we explore the biology, genomics and patterns of response to EGFR-inhibitors to inform identification of potential biomarkers, highlighting several key molecules that have shown promise in preclinical studies and clinical trials across multiple cancer sites.

Personalized treatment of advanced non-small-cell lung cancer in routine clinical practice

Personalized treatment of patients with advanced non-small-cell lung cancer based on clinical and molecular tumor features has entered clinical routine practice. The 2015 pathological classification of lung cancer mandates immunohistochemical and molecular analysis. Therapeutic strategies focused on inhibition of angiogenesis and growth factor receptor signaling. Inhibitors of angiogenesis and monoclonal antibodies directed against the epidermal growth factor receptor have shown efficacy in combination with chemotherapy. Mutations in the epidermal growth factor receptor and anaplastic lymphoma kinase have become clinically relevant therapeutic targets. Immune checkpoint inhibitors are also entering routine clinical practice. Identification of predictive biomarkers is essential and faces several challenges including tumor heterogeneity and dynamic changes of tumor features over time. Liquid biopsies may overcome some of these challenges in the future.

Defining a Radiomic Response Phenotype: A Pilot Study using targeted therapy in NSCLC

Medical imaging plays a fundamental role in oncology and drug development, by providing a non-invasive method to visualize tumor phenotype. Radiomics can quantify this phenotype comprehensively by applying image-characterization algorithms, and may provide important information beyond tumor size or burden. In this study, we investigated if radiomics can identify a gefitinib response-phenotype, studying high-resolution computed-tomography (CT) imaging of forty-seven patients with early-stage non-small cell lung cancer before and after three weeks of therapy. On the baseline-scan, radiomic-feature Laws-Energy was significantly predictive for EGFR-mutation status (AUC = 0.67, p = 0.03), while volume (AUC = 0.59, p = 0.27) and diameter (AUC = 0.56, p = 0.46) were not. Although no features were predictive on the post-treatment scan (p > 0.08), the change in features between the two scans was strongly predictive (significant feature AUC-range = 0.74–0.91). A technical validation revealed that the associated features were also highly stable for test-retest (mean ± std: ICC = 0.96 ± 0.06). This pilot study shows that radiomic data before treatment is able to predict mutation status and associated gefitinib response non-invasively, demonstrating the potential of radiomics-based phenotyping to improve the stratification and response assessment between tyrosine kinase inhibitors (TKIs) sensitive and resistant patient populations.

Blood-based markers of efficacy and resistance to cetuximab treatment in metastatic colorectal cancer: results from CALGB 80203 (Alliance)

Circulating protein markers were assessed in patients with colorectal cancer (CRC) treated with cetuximab in CALGB 80203 to identify prognostic and predictive biomarkers. Patients with locally advanced or metastatic CRC received FOLFOX or FOLFIRI chemotherapy (chemo) or chemo in combination with cetuximab. Baseline plasma samples from 152 patients were analyzed for six candidate markers [epidermal growth factor (EGF), heparin‐binding EGF (HBEGF), epidermal growth factor receptor (EGFR), HER2, HER3, and CD73]. Analyte levels were associated with survival endpoints using univariate Cox proportional hazards models. Predictive markers were identified using a treatment‐by‐marker interaction term in the Cox model. Plasma levels of EGF, HBEGF, HER3, and CD73 were prognostic for overall survival (OS) across all patients (KRAS mutant and wild‐type). High levels of EGF predicted for lack of OS benefit from cetuximab in KRAS wild‐type (WT) patients (chemo HR = 0.98, 95% CI = 0.74–1.29; chemo+cetuximab HR = 1.54, 95% CI = 1.05–2.25; interaction P = 0.045) and benefit from cetuximab in KRAS mutant patients (chemo HR = 1.72, 95% CI = 1.02–2.92; chemo+cetuximab HR = 0.90, 95% CI = 0.67–1.21; interaction P = 0.026). Across all patients, higher HER3 levels were associated with significant OS benefit from cetuximab treatment (chemo HR = 4.82, 95% CI = 1.68–13.84; chemo+cetuximab HR = 0.95, 95% CI = 0.31–2.95; interaction P = 0.046). CD73 was also identified as predictive of OS benefit in KRASWT patients (chemo HR = 1.28, 95% CI = 0.88–1.84; chemo+cetuximab HR = 0.60, 95% CI = 0.32–1.13; interaction P = 0.049). Although these results are preliminary, and confirmatory studies are necessary before clinical application, the data suggest that HER3 and CD73 may play important roles in the biological response to cetuximab.

EGFR-GRB2 Protein Colocalization Is a Prognostic Factor Unrelated to Overall EGFR Expression or EGFR Mutation in Lung Adenocarcinoma

INTRODUCTION

EGFR is a therapeutic target in NSCLC for EGFR-mutant patients. Proximity ligation assay (PLA) is a method to detect functional signaling associated protein complexes. Growth factor receptor bound protein 2 (GRB2) is an adaptor protein that binds to the phosphorylated residues of active EGFR. Interaction of EGFR and GRB2 correlates with active EGFR signaling and leads to activation of the MAPK/ERK pathway.

METHODS

A PLA developed to detect EGFR-GRB2 interaction was measured by quantitative immunofluorescence using Automated Quantitative Analysis technology. EGFR pathway activation was assessed in patients with NSCLC with different mutation status along with overall EGFR expression. Additionally, the PLA to detect EGFR-GRB2 interaction was evaluated as a prognostic marker in two cohorts of patients with lung adenocarcinoma.

RESULTS

The PLA to detect EGFR-GRB2 interaction was unrelated to overall EGFR expression or mutation in a series of patients with NSCLC with known mutation status. EGFR-mutant (p = 0.04) and EGFR/KRAS wild-type tumors (p = 0.0049) had significantly higher EGFR pathway activation compared with KRAS-mutant cases, with no significant difference shown between mutation sites. In two series of patients with lung adenocarcinoma, the PLA to detect EGFR-GRB2 interaction was independently associated with longer survival (hazard ratio = 0.46, 95% confidence interval: 0.2-0.78, p = 0.0085 and hazard ratio = 0.48, 95% confidence interval: 0.2-0.85, p = 0.017). Total EGFR protein expression alone was not correlated with outcome.

CONCLUSIONS

EGFR colocalization with GRB2 as assessed by PLA is not correlated with EGFR expression levels or mutation status, defining a patient group that may show EGFR pathway activation, as illustrated by its prognostic value. Future studies may determine whether this group is more likely to respond to EGFR-targeted therapies.

First-line treatment of advanced epidermal growth factor receptor (EGFR) mutation positive non-squamous non-small cell lung cancer

BACKGROUND

Epidermal growth factor receptor (EGFR) mutation positive (M+) non-small cell lung cancer (NSCLC) is emerging as an important subtype of lung cancer comprising 10% to 15% of non-squamous tumours. This subtype is more common in women than men and is less associated with smoking.

OBJECTIVES

To assess the clinical effectiveness of single -agent or combination EGFR therapies used in the first-line treatment of people with locally advanced or metastatic EGFR M+ NSCLC compared with other cytotoxic chemotherapy (CTX) agents used alone or in combination, or best supportive care (BSC). The primary outcome was overall survival. Secondary outcomes included progression-free survival, response rate, toxicity, and quality of life.

SEARCH METHODS

We conducted electronic searches of the the Cochrane Register of Controlled Trials (CENTRAL) (2015, Issue 6), MEDLINE (1946 to 1 June 2015), EMBASE (1980 to 1 June 2015), and ISI Web of Science (1899 to 1 June 2015). We also searched the conference abstracts of the American Society for Clinical Oncology and the European Society for Medical Oncology (1 June 2015); Evidence Review Group submissions to the National Institute for Health and Care Excellence; and the reference lists of retrieved articles.

SELECTION CRITERIA

Parallel randomised controlled trials comparing EGFR-targeted agents (alone or in combination with cytotoxic agents or BSC) with cytotoxic chemotherapy (single or doublet) or BSC in chemotherapy-naive patients with locally advanced or metastatic (stage IIIB or IV) EGFR M+ NSCLC unsuitable for treatment with curative intent.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified articles, extracted data, and carried out the 'Risk of bias' assessment. We conducted meta-analyses using a fixed-effect model unless there was substantial heterogeneity, in which case we also performed a random-effects analysis as a sensitivity analysis.

MAIN RESULTS

Nineteen trials met the inclusion criteria. Seven of these exclusively recruited people with EGFR M+ NSCLC; the remainder recruited a mixed population and reported results for people with EGFR M+ NSCLC as subgroup analyses. The number of participants with EGFR M+ tumours totalled 2317, of whom 1700 were of Asian origin.Overall survival (OS) data showed inconsistent results between the included trials that compared EGFR-targeted treatments against cytotoxic chemotherapy or placebo.Erlotinib was the intervention treatment used in eight trials, gefitinib in seven trials, afatinib in two trials, and cetuximab in two trials. The findings of one trial (FASTACT 2) did report a statistically significant OS gain for participants treated with erlotinib plus cytotoxic chemotherapy when compared to cytotoxic chemotherapy alone, but this result was based on a small number of participants (n = 97). For progression-free survival (PFS), a pooled analysis of 3 trials (n = 378) demonstrated a statistically significant benefit for erlotinib compared with cytotoxic chemotherapy (hazard ratio (HR) 0.30; 95% confidence interval (CI) 0.24 to 0.38).In a pooled analysis with 491 participants administered gefitinib, 2 trials (IPASS and NEJSG) demonstrated a statistically significant PFS benefit of gefitinib compared with cytotoxic chemotherapy (HR 0.39; 95% CI 0.32 to 0.48).Afatinib (n = 709) showed a statistically significant PFS benefit when compared with chemotherapy in a pooled analysis of 2 trials (HR 0.42; 95% CI 0.34 to 0.53).Commonly reported grade 3/4 adverse events for afatinib, erlotinib, and gefitinib monotherapy were rash and diarrhoea. Myelosuppression was consistently worse in the chemotherapy arms, fatigue and anorexia were also associated with some chemotherapies.No statistically significant PFS or OS benefit for cetuximab plus cytotoxic chemotherapy (n = 81) compared to chemotherapy alone was reported in either of the two trials.Six trials reported on quality of life and symptom improvement using different methodologies. For each of erlotinib, gefitinib, and afatinib, 2 trials showed improvement in one or more indices for the tyrosine-kinase inhibitor (TKI) compared to chemotherapy.The quality of evidence was high for the comparisons of erlotinib and gefitinib with cytotoxic chemotherapy and for the comparison of afatinib with cytotoxic chemotherapy.

AUTHORS' CONCLUSIONS

Erlotinib, gefitinib, and afatinib are all active agents in EGFR M+ NSCLC patients, and demonstrate an increased tumour response rate and prolonged progression-free survival compared to cytotoxic chemotherapy. We also found a beneficial effect of the TKI compared to cytotoxic chemotherapy. However, we found no increase in overall survival for the TKI when compared with standard chemotherapy. Cytotoxic chemotherapy is less effective in EGFR M+ NSCLC than erlotinib, gefitinib, or afatinib and is associated with greater toxicity. There were no data supporting the use of monoclonal antibody therapy.

KRAS-Mutant Lung Cancers in the Era of Targeted Therapy

KRAS-mutant lung cancers account for approximately 25% of non-small cell lung carcinomas, thus representing an enormous burden of cancer worldwide. KRAS mutations are clear drivers of tumor growth and are characterized by a complex biology involving the interaction between mutant KRAS, various growth factor pathways, and tumor suppressor genes. While KRAS mutations are classically associated with a significant smoking history, they are also identified in a substantial proportion of never-smokers. These mutations are found largely in lung adenocarcinomas with solid growth patterns and tumor-infiltrating lymphocytes. A variety of tools are available for diagnosis including Sanger sequencing, multiplex mutational hotspot profiling, and next-generation sequencing. The prognostic and predictive roles of KRAS status remain controversial. It has become increasingly clear, however, that KRAS mutations drive primary resistance to EGFR tyrosine kinase inhibition. Until recently, mutant KRAS was not thought of as a clinically-targetable driver in lung cancers. With the expansion of our knowledge regarding the biology of KRAS-mutant lung cancers and the role of MEK and PI3K/mTOR inhibition, the face of targeted therapeutics for this genomic subset of patients is slowly beginning to change.

Heads Up! Predictive Gene Signatures in Head and Neck Cancer May Be Coming Soon

Cetuximab-platinum chemotherapy is used for recurrent/metastatic head and neck squamous cell carcinoma (HNSCC); however, a minority of patients benefit. Gene expression profiling (GEP) of HNSCCs with prolonged responses to cetuximab-chemotherapy demonstrate basal subtype traits including signatures of EGFR signaling and hypoxic differentiation. GEP of short-response patients show RAS activation. Clin Cancer Res; 22(15); 3710-2. ©2016 AACRSee related article by Bossi et al., p. 3961.

Prognostic impact of KRAS mutation subtypes in 677 patients with metastatic lung adenocarcinomas

BACKGROUND

We previously demonstrated that patients with metastatic KRAS mutant lung cancers have a shorter survival compared with patients with KRAS wild-type cancers. Recent reports have suggested different clinical outcomes and distinct activated signaling pathways depending on KRAS mutation subtype. To better understand the impact of KRAS mutation subtype, we analyzed data from 677 patients with KRAS mutant metastatic lung cancer.

METHODS

We reviewed all patients with metastatic or recurrent lung cancers found to have KRAS mutations over a 6-year time period. We evaluated the associations among KRAS mutation type, clinical factors, and overall survival in univariate and multivariate analyses. Any significant findings were validated in an external multi-institution patient dataset.

RESULTS

Among 677 patients with KRAS mutant lung cancers (53 at codon 13, 624 at codon 12), there was no difference in overall survival for patients when comparing KRAS transition versus transversion mutations (p = 0.99), smoking status (p = 0.33), or when comparing specific amino acid substitutions (p = 0.20). In our dataset, patients with KRAS codon 13 mutant tumors (n = 53) had shorter overall survival compared with patients with codon 12 mutant tumors (n = 624) (1.1 versus 1.3 years, respectively; p = 0.009), and the findings were confirmed in a multivariate Cox model controlling for age, sex, and smoking status (hazard ratio: 1.52, 95% confidence interval: 1.11-2.08; p = 0.008). In an independent validation set of tumors from 682 patients with stage IV KRAS mutant lung cancers, there was no difference in survival between patients with KRAS codon 13 versus codon 12 mutations (1.0 versus 1.1 years, respectively; p = 0.41).

CONCLUSIONS

Among individuals with KRAS mutant metastatic lung cancers treated with conventional therapy, there are no apparent differences in outcome based on KRAS mutation subtype.

KRAS Mutation as a Biomarker for Survival in Patients with Non-Small Cell Lung Cancer, A Meta-Analysis of 12 Randomized Trials

BACKGROUND

Because there is no clear consensus for the prognostic implication of KRAS mutations in patients with non-small cell lung cancer (NSCLC), we conducted a meta-analysis based on 12 randomized trials to draw a more accurate conclusion.

MATERIALS AND METHODS

A systematic computer search of articles from inception to May 1, 2014 using the PubMed, EMBASE, and Cochrane databases was conducted. The enrollment of articles and extraction of data were independently performed by two authors.

RESULTS

Our analysis was based on the endpoints overall survival (OS) and progression-free survival (PFS). Nine records (All for OS, 7 for PFS) comprising 12 randomized trials were identified with 3701 patients who underwent a test for KRAS mutations. In the analysis of the pooled hazard ratios (HRs) for OS (HR: 1.39; 95% confidence interval [CI] 1.23-1.56) and PFS (HR: 1.33; 95% CI 1.17-1.51), we found that KRAS mutations are related to poor survival benefit for NSCLC. According to a subgroup analysis stratified by disease stage and line of therapy, the combined HRs for OS and PFS coincided with the finding that the presence of a KRAS mutation is a dismal prognostic factor. However, the prognostic role of KRAS mutations are not statistically significant in a subgroup analysis of patients treated with chemotherapy in combination with cetuximab based on the endpoints OS (P=0.141) and PFS (P=0.643).

CONCLUSIONS

Our results indicate that KRAS mutations are associated with inferior survival benefits for NSCLC but not for those treated with chemotherapies integrating cetuximab.

[KRAS and bronchial adenocarcinoma. Between disappointments and hopes]

A better understanding of oncogenesis and the development of targeted therapies have led to improved outcomes in the treatment of lung cancer. KRAS mutation has the potential to drive the oncogenesis of almost one third of lung adenocarcinomas but it leads to a highly complex proliferation signal involving multiple signaling pathways, explaining the disappointing results of various inhibition strategies of K-ras or its effectors. Nevertheless, recent data suggest different roles of distinct KRAS mutation subtypes and KRAS interactions with new genes in the field of synthetic lethality mechanisms open the way to new therapeutic possibilities. This review aims to provide an overview of: 1) epidemiological data and particularly the prognostic impact of KRAS mutations in non-small cell lung cancer, 2) the results of different drugs either being tested in humans or sources of hope.

Epidermal growth factor receptor-directed monoclonal antibodies in nonsmall cell lung cancer: an update

PURPOSE OF REVIEW

The epidermal growth factor receptor (EGFR) is overexpressed in many nonsmall cell lung cancers (NSCLCs). Blockade of EGFR by monoclonal antibodies has been studied as a strategy to improve the outcome of first-line chemotherapy in patients with NSCLC. The present review updates the findings from phase III trials.

RECENT FINDINGS

Cetuximab improved survival when combined with first-line chemotherapy and this benefit was limited to patients with high EGFR expression in their tumors. A Southwest Oncology Group study currently prospectively evaluates the predictive biomarkers for cetuximab. In the SQUIRE phase III trial, necitumumab added to cisplatin and gemcitabine increased the survival in patients with advanced squamous cell NSCLC. The INSPIRE trial studied chemotherapy with and without necitumumab in patients with nonsquamous NSCLC but was prematurely halted because of increased thromboembolic events with chemotherapy and necitumumab.

SUMMARY

EGFR monoclonal antibodies improved the outcome including survival in selected patients with advanced NSCLC. Prospective validation of predictive biomarkers is ongoing.

What is the best strategy for targeting EGF receptors in non-small-cell lung cancer?

EGF receptors (EGFRs) are often overexpressed or constitutively activated in non-small-cell lung cancer, and are an important therapeutic target. EGFR signaling can be blocked with tyrosine kinase inhibitors (TKIs) and anti-EGFR antibodies. Three EGFR-TKIs are approved as initial monotherapies in patients with EGFR-activating mutations, and erlotinib has a role as maintenance and second-line therapy. Investigational anti-EGFR monoclonal antibodies plus standard first-line therapy improve survival in patients with advanced non-small-cell lung cancer, especially in tumors with high EGFR expression. Anti-EGFR antibodies inhibit EGFR signaling and have the potential to stimulate antibody-dependent cell-mediated cytotoxicity. Multikinase TKIs are investigational as first- and second-line therapies, as monotherapies and in combination with chemotherapy. This article summarizes the available clinical data for EGFR-targeted therapies.

CHAMP: A Phase II Study of Panitumumab With Pemetrexed and Cisplatin Versus Pemetrexed and Cisplatin in the Treatment of Patients With Advanced-Stage Primary Nonsquamous Non-Small-Cell Lung Cancer With Particular Regard to the KRAS Status

INTRODUCTION

The aim of the study was to investigate the efficacy and tolerability of panitumumab, a fully human antiepidermal growth factor receptor monoclonal antibody, in combination with pemetrexed/cisplatin in patients with stage IIIB to IV primary nonsquamous non-small-cell lung cancer and wild type V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS). Results were compared with those obtained in a control group of patients who received a pemetrexed/cisplatin regimen only.

PATIENTS AND METHODS

This was a phase II, randomized, open-label study with 2 treatment arms. In total, 96 patients received panitumumab at a dose of 9 mg/kg in combination with pemetrexed 500 mg/m(2) and cisplatin 75 mg/m(2) (n = 49) or pemetrexed/cisplatin alone (n = 47). The primary outcome measure was progression-free survival at 6 months. Secondary end points of the study included overall survival, tumor response, quality of life, and safety outcomes. The CHAMP study is registered with ClinicalTrials.gov, number NCT01088620.

RESULTS

Progression-free survival at 6 months did not indicate a benefit of panitumumab as a supplement to the standard therapy of pemetrexed/cisplatin whereas the overall survival showed a clear difference between the treatment groups in favor of the standard therapy. Results might be affected by the higher rates of serious adverse events and higher death rates within the panitumumab arm.

CONCLUSIONS

Results from the present study indicate that combination of cisplatin/pemetrexed with panitumumab should not be recommended for patients with adenocarcinoma and KRAS wild type because of lack of efficacy, lack of improvement of quality of life, and because of the increase in toxicity rates compared with patients in the control arm, who received standard chemotherapy of pemetrexed/cisplatin.

Rationale for targeting the ErbB family of receptors in patients with advanced squamous cell carcinoma of the lung

Squamous cell carcinoma (SCC) of the lung represents around 30% of all non-small-cell lung cancers. Treatment options for nonsquamous histology have increased in recent years following the development of pemetrexed chemotherapy and the identification of activating EGFR mutations and ALK rearrangements as targets for effective noncytotoxic agents. By contrast, until recently the development of new therapies for SCC has lagged behind. However, the identification of important genetic events driving SCC, including a greater understanding of the role of the ErbB receptor family in SCC pathogenesis, as well as recent immunotherapy advances, have led to new treatment options for SCC.