Dual Targeting of the Vascular Endothelial Growth Factor and Epidermal Growth Factor Receptor Pathways: Rationale and Clinical Applications for Non-Small-Cell Lung Cancer

Non-small cell lung cancer: an update on emerging EGFR-targeted therapies

INTRODUCTION

Current research in EGFR-mutated NSCLC focuses on the management of drug resistance and uncommon mutations, as well as on the opportunity to extend targeted therapies' field of action to earlier stages of disease.

AREAS COVERED

We conducted a review analyzing literature from the PubMed database with the aim to describe the current state of art in the management of EGFR-mutated NSCLC, but also to explore new strategies under investigation. To this purpose, we collected recruiting phase II-III trials registered on Clinicaltrials.govand conducted on EGFR-mutated NSCLC both in early and advanced stage.

EXPERT OPINION

With this review, we want to provide an exhaustive overview of current and new potential treatments in EGFR-mutated NSCLC, with emphasis on the most promising newly investigated strategies, such as association therapies in the first-line setting involving EGFR-TKIs and chemotherapy (FLAURA2) or drugs targeting different driver pathways (MARIPOSA). We also aimed at unearthing challenges to achieve in this field, specifically the need to fully exploit already available compounds while developing new ones, the management of new emerging toxicities and the necessity to improve our biological understanding of the disease to design trials with a solid scientific rationale and to allow treatment personalization such in case of uncommon mutations.

Iodoquinazoline-derived VEGFR-2 and EGFRT790M dual inhibitors: Design, synthesis, molecular docking and anticancer evaluations

Herein, we report the synthesis of a series of new fourteen iodoquinazoline derivatives 7a-c to 13a-e and their evaluation as potential anticancer agents via dual targeting of EGFRT790M and VEGFR-2. The new derivatives were designed according to the target receptors structural requirements. The compounds were evaluated for their cytotoxicity against HepG2, MCF-7, HCT116 and A549 cancer cell lines using MTT assay. Compound 13e showed the highest anticancer activities with IC50 = 5.70, 7.15, 5.76 and 6.50 µM against HepG2, MCF-7, HCT116 and A549 cell lines correspondingly. Compounds 7c, 9b and 13a-d exhibited very good anticancer effects against the tested cancer cell lines. The highly effective six derivatives 7c, 10, 13b, 13c, 13d and 13e were examined against VERO normal cell lines to estimate their cytotoxic capabilities. Our conclusion revealed that compounds 7c, 10, 13b, 13c, 13d and 13e possessed low toxicity against VERO normal cells with IC50 prolonging from 41.66 to 53.99 μM. Also compounds 7a-c to 13a-e were further evaluated for their inhibitory activity against EGFRT790M and VEGFR-2. Also, their ability to bind with both EGFR and VEGFR-2 receptors was examined by molecular modeling. Compounds 13e, 13d, 7c and 13c excellently inhibited VEGFR-2 activity with IC50 = 0.90, 1.00, 1.25 and 1.50 µM respectively. Moreover, Compounds 13e, 7c, 10 and 13d excellently inhibited EGFRT790M activity with IC50 = 0.30, 0.35, 0.45 and 0.47 µM respectively. Finally, our derivatives 7b, 13d and 13e showed good in silico calculated ADMET profile.

Addition of bevacizumab to EGFR tyrosine kinase inhibitors in advanced NSCLC: an updated systematic review and meta-analysis

Background: The synergistic effects of antiangiogenic inhibitor bevacizumab and epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKI) therapy were encouraging in patients with EGFR-mutant advanced NSCLC, though some controversy remains. The specific subgroup of patients who might benefit most from the EGFR-TKI and bevacizumab combination therapy is yet to be determined. Methods: Randomized clinical trials (RCTs) that had compared the clinical efficacy of EGFR-TKI and bevacizumab combination therapy with EGFR-TKI monotherapy in treating EGFR-mutant advanced NSCLC patients published before 23 December 2022 were searched in the Cochrane, PubMed and Embase. We performed a meta-analysis for the overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and treatment-related adverse events with a grade equal or more than 3 (grade≥3 TRAEs). Subgroup analyses of PFS and OS stratified by clinical characteristics and treatment were conducted. Results: We included 10 RCTs involving 1520 patients. Compared with EGFR-TKI monotherapy, addition of bevacizumab to EGFR-TKI resulted in a significantly higher PFS (hazard ratio (HR) = 0.74, 95% confidence interval (95% CI): 0.62-0.87)) and ORR (risk ratio (RR) = 1.07, 95% CI: 1.01-1.13). However, no significant difference in OS (HR = 0.96, 95% CI: 0.83-1.12) was noticed. Patients with EGFR-mutant advanced NSCLC receiving combination therapy showed PFS improvement regardless of gender (male or female), Eastern Cooperative Oncology Group performance status (0 or 1), baseline central nervous system (CNS) metastasis (presence or absence) and EGFR mutation type (19del or 21L858R). Subgroup analyses showed that, with the treatment of bevacizumab and EGFR-TKI, patients who ever smoked achieved significantly better OS and PFS benefits (HR = 0.68, 95% CI: 0.48-0.95; HR = 0.59, 95% CI: 0.46-0.74, respectively), and those aged <75 years and the Asian population had significantly prolonged PFS (HR = 0.69, 95% CI: 0.52-0.91; HR = 0.71, 95% CI: 0.58-0.87; respectively). The superiority of EGFR-TKI and bevacizumab combination therapy against EGFR-TKI monotherapy in improving PFS was more significant in the erlotinib regimen subgroup. The risk of grade≥3 TRAEs was remarkably higher in the combination therapy group (HR = 1.73, 95% CI: 1.39-2.16). Conclusion: Addition of bevacizumab to EGFR-TKI therapy provided significantly better PFS and ORR for EGFR-mutant advanced NSCLC patients, though with higher risk of grade≥3 TRAEs. Patients who ever smoked, aged <75 years, and Asian population might benefit more from the combination regimen. Systematic Review Registration: This systematic review and meta-analysis was registered in the PROSPERO database (CRD42023401926).

Design, synthesis, docking, ADMET and anticancer evaluations of N-alkyl substituted iodoquinazoline derivatives as dual VEGFR-2 and EGFR inhibitors

Fifteen new 1-alkyl-6-iodoquinazoline derivatives 5a-d to 9a-e were designed and synthesized and their anticancer activities were evaluated against HepG2, MCF-7, HCT116 and A549 cancer cell lines via dual targeting of EGFR and VEGFR-2. The newly synthesized compounds were designed based on the structure requirements of the target receptors and were confirmed using spectral data. Compound 9c showed the highest anticancer activities with EC50 = 5.00, 6.00, 5.17 and 5.25 μM against HepG2, MCF-7, HCT116 and A549 cell lines correspondingly. Moreover, compounds 5d, 8b, 9a, 9b, 9d, and 9e exhibited very good anticancer effects against the tested cancer cell lines. The highly effective seven derivatives 5d, 8b, 9a-e were examined against VERO normal cell lines to estimate their cytotoxic capabilities. Compounds 9c, 9b, 9d, 9a, 9e and 5d excellently inhibited VEGFR-2 activity with IC50 = 0.85, 0.90, 0.90, 1.00, 1.20 and 1.25 μM respectively. Moreover, compounds 9c, 9d, 9e, 5d, 8b and 9b excellently inhibited EGFRT790M activity with IC50 = 0.22, 0.26, 0.30, 0.40, 0.45 and 0.50 μM respectively. Also, compounds 9c, 9d and 9e excellently inhibited EGFRWT activity with IC50 = 0.15, 0.20 and 0.25 μM respectively. As planned, compound 9c showed excellent dual EGFR/VEGFR-2 inhibitory activities. Consonantly, ADMET study was calculated in silico for the supreme three worthwhile compounds 9b, 9c and 9e in contrast to sorafenib and erlotinib as reference drugs. The obtained results concluded that, our compounds might be useful as prototype for design, optimization, adaptation and investigation to have more powerful and selective dual VEGFR-2/EGFRT790M inhibitors with higher antitumor activity.

Pharmacokinetics, safety, tolerability, and feasibility of apatinib in combination with gefitinib in stage IIIB-IV EGFR-mutated non-squamous NSCLC: a drug-drug interaction study

PURPOSE

Apatinib combined with gefitinib was proven to benefit advanced EGFR-mutant NSCLC patients in first-line treatment. This study aimed to evaluate the drug-drug interaction of gefitinib and apatinib when coadministered in EGFR-mutated NSCLC patients.

METHODS

In this phase 1b, multi-center, open-label, fixed-sequence study, the drug-drug interaction of gefitinib and apatinib was evaluated when coadministered in EGFR-mutated NSCLC patients. Patients received single-agent apatinib 500 mg QD on days 1-4. Gefitinib 250 mg QD was given on days 5-15 and combined with apatinib 500 mg QD on days 12-15. Serial blood samples were drawn on days 4 and 15. The plasma concentrations and other pharmacokinetics parameters were measured for apatinib with and without gefitinib.

RESULTS

The study enrolled 22 patients and 20 were analyzed for pharmacokinetics. There were no distinct differences in apatinib Cmax and AUC0-τ with versus without gefitinib (geometric LSM ratio, 0.96 [90% CI 0.84-1.10] for Cmax and 1.12 [90% CI 0.96-1.30] for AUC0-τ). Similar PFS and grade of treatment-emergent adverse events (TEAEs) were found between different Cmax and AUC0-τ of apatinib and gefitinib at 500 mg apatinib and 250 mg gefitinib dose levels.

CONCLUSIONS

Apatinib pharmacokinetics parameters were not significantly changed when coadministered with gefitinib. All TEAEs were manageable, and there was no need to change the dose level when combining apatinib and gefitinib (ClinicalTrials.gov identifier: NCT04390984, May 18, 2020).

New quinazoline sulfonamide derivatives as potential anticancer agents: Identifying a promising hit with dual EGFR/VEGFR-2 inhibitory and radiosensitizing activity

Herein, we report the synthesis of a series of new quinazoline sulfonamide conjugates 2-16 and their evaluation as potential anticancer agents via dual targeting of EGFRT790M and VEGFR-2. The newly synthesized compounds were designed based on the structure requirements of the target receptors and were confirmed using spectral data. The compounds were evaluated for their cytotoxicity against four cancer cell lines (HepG2, MCF-7, HCT116 and A549) using MTT assay. The most active compounds were further evaluated for their inhibitory activity against EGFRT790M and VEGFR-2. Compound 15 showed the most significant cytotoxic activity with IC50 = 0.0977 µM against MCF-7 and the most potent inhibitory activity against both EGFR and VEGFR with IC50 = 0.0728 and 0.0523 µM, respectively. Compound 15 was able to induce apoptosis in MCF-7 cells and cell cycle arrest at the G2/M phase. The relative safety profile of 15 was assessed using HEK-293 normal cell line and an ADMET profile was carried out. Radiosensitizing evaluation of 15 proved its significant ability to sensitize the cancer cell to the effect of radiation after being subjected to a single dose of 8 Gy gamma irradiation. Molecular docking studies revealed that 15 could bind to the ATP-binding site of EGF and VEGF receptors, inhibiting their activity.

First-Generation Epidermal Growth Factor Receptor Inhibitors Plus Antiangiogenic Drugs Versus Third-Generation Epidermal Growth Factor Receptor Inhibitors in Advanced Non-Small-Cell Lung Cancer: A Meta-Analysis

PURPOSE

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) revolutionized the therapeutic landscape of non-small-cell lung cancer (NSCLC). However, despite significant survival improvement, the emergence of resistance mechanisms represents a common event. In this meta-analysis, we compared the efficacy and safety of third-generation EGFR-TKIs, the current standard of care, to first-generation EGFR-TKIs with antiangiogenic drugs for the first-line treatment of NSCLC harboring EGFR mutations.

MATERIALS AND METHODS

Randomized controlled clinical trials (RCTs) reporting survival data published before September 1, 2022, were searched through the MEDLINE databases (PubMed), the Cochrane Database of Systematic Reviews, and Central Register of Controlled Trials (Wiley). Progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and grade 3 or higher treatment-related adverse events (≥3 TRAEs) data were analyzed.

RESULTS

Twelve RCTs were included in our meta-analysis, with a total of 3,565 patients. We observed that third-generation EGFR-TKIs and first-generation EGFR-TKIs combined with antiangiogenic drugs provided a similar OS benefit over first-generation EGFR-TKIs in any of the subgroups. However, we indirectly observed a greater PFS benefit of third-generation EGFR-TKIs over first-generation EGFR-TKIs in females, never-smokers, in patients harboring exon 19 deletions, and in those with brain metastasis, as compared with using first-generation EGFR-TKIs plus antiangiogenic drugs. The ORR did not differ between the combination strategy and third-generation EGFR-TKIs. Finally, the risk of developing grade ≥3 TRAEs was higher using the combination of first-generation EGFR-TKIs and antiangiogenic drugs over first-generation EGFR-TKIs than third-generation EGFR-TKIs over first-generation EGFR-TKIs.

CONCLUSION

This meta-analysis suggests that the combination strategy may provide an alternative to third-generation EGFR-TKIs, but more data are needed to determine the predictive clinicopathologic characteristics that can influence the treatment choice. Until then, third-generation EGFR-TKIs still represent the first choice in advanced NSCLC harboring EGFR mutations.

Efficacy and Toxicity of Combined Inhibition of EGFR and VEGF in Patients With Advanced Non-small Cell Lung Cancer Harboring Activating EGFR Mutations: A Systematic Review and Meta-analysis

Dual inhibition of epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) pathways have demonstrated promising results for treatment of advanced non-small cell lung cancer. We conducted a systematic review and meta-analysis to assess the efficacy and toxicity of the combined treatment with EGFR tyrosine kinase inhibitors (TKIs) and VEGF blockade for patients with advanced non-small cell lung cancer harboring activating EGFR mutations, in comparison to EGFR TKIs alone. The electronic databases were searched for relevant randomized trials between 2000 and 2022. The primary endpoints were overall survival (OS) and progression-free survival. Secondary endpoints included objective response rate (ORR), disease control rate, and grade ≥3 adverse events (AEs). The pooled hazard ratios (HR) and odds ratios were meta-analyzed using the generic inverse variance and the Mantel-Haenszel methods. A total of 1528 patients from 8 trials were evaluated for analyses. The combination treatment decreased the risk of disease progression by 37% (HR=0.63; 95% CI, 0.56 to 0.72) but had no added benefit on OS compared with EGFR inhibition alone (HR=0.90; 95% CI, 0.76 to 1.05). There was no significant difference in objective response rate or disease control rate between treatments. There was a significantly increased number of AEs reported in the dual treatment arm (odds ratio=3.02; 95% CI, 1.71 to 5.31), with proteinuria and hypertension being the most significantly increased AEs. This meta-analysis suggests combined inhibition of EGFR and VEGF pathways significantly improves progression-free survival, with no OS benefit, and increases AEs. Mature OS data are needed along with results from more trials exploring this strategy with third-generation EGFR TKIs to strengthen these results.

Treatment Strategies for Non-Small Cell Lung Cancer with Common EGFR Mutations: A Review of the History of EGFR TKIs Approval and Emerging Data

The development of targeted therapies over the past two decades has led to a dramatic change in the management of EGFR-mutant non-small cell lung cancer (NSCLC). While there are currently five approved EGFR tyrosine kinase inhibitors (TKIs) for treating EGFR-mutant NSCLC in the first-line setting, therapy selection after progression on EGFR TKIs remains complex. Multiple groups are investigating novel therapies and drug combinations to determine the optimal therapy and treatment sequence for these patients. In this review, we summarize the landmark trials and history of the approval of EGFR TKIs, their efficacy and tolerability, and the role of these therapies in patients with central nervous system metastasis. We also briefly discuss the mechanisms of resistance to EGFR TKIs, ongoing attempts to overcome resistance and improve outcomes, and finalize by offering treatment sequencing recommendations.

The Molecular and Cellular Strategies of Glioblastoma and Non-Small-Cell Lung Cancer Cells Conferring Radioresistance

Ionizing radiation (IR) has been shown to play a crucial role in the treatment of glioblastoma (GBM; grade IV) and non-small-cell lung cancer (NSCLC). Nevertheless, recent studies have indicated that radiotherapy can offer only palliation owing to the radioresistance of GBM and NSCLC. Therefore, delineating the major radioresistance mechanisms may provide novel therapeutic approaches to sensitize these diseases to IR and improve patient outcomes. This review provides insights into the molecular and cellular mechanisms underlying GBM and NSCLC radioresistance, where it sheds light on the role played by cancer stem cells (CSCs), as well as discusses comprehensively how the cellular dormancy/non-proliferating state and polyploidy impact on their survival and relapse post-IR exposure.

An updated network meta-analysis of EGFR-TKIs and combination therapy in the first-line treatment of advanced EGFR mutation positive non-small cell lung cancer

Objectives

Tyrosine kinase inhibitors (TKIs) are a standard care option in patients with non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutation. TKI-based combination treatment modes show encouraging outcomes. However, it remains unknown which is the optimal treatment as the first-line regimen for these patients on overall survival (OS).

Materials and methods

Randomized controlled trials and meeting abstracts that investigated EGFR-TKIs alone or in combination as front-line care for patients with NSCLC were systematically searched in relevant databases and reviewed. Fixed and random effects network meta-analysis models were used to estimate progression-free survival (PFS), OS, overall response rate, and grade three and higher adverse events (AEs). Surface under the cumulative ranking curves (SUCRAs) were used to rank treatment effects.

Results

Eighteen studies covering six treatments and involving a total of 4389 patients were included in this network meta-analysis. On OS, the top three treatment were first-generation EGFR-TKIs (1G EGFR-TKIs) plus chemotherapy (SUCRA, 88.1%), osimertinib (SUCRA, 65.8%) and second-generation EGFR-TKIs (2GEGFR-TKIs) (SUCRA, 63.3%). On PFS, the top three treatments were osimertinib (SUCRA, 96.0%), 1G EGFR-TKIs plus chemotherapy (SUCRA, 67.1%), and 1G EGFR-TKIs plus antiangiogenesis (SUCRA, 48.2%). Two types of TKI-based combination therapy have significantly higher risk of grade three and higher AEs than TKI alone.

Conclusion

1G EGFR-TKIs plus chemotherapy and osimertinib seem to be the two better options as first-line care in advanced NSCLC patients with EGFR-mutation. Osimertinib caused the lowest incidence of AEs. However, TKIs-based combination therapy significantly increased AEs.

A multifunctional nanotheranostic agent potentiates erlotinib to EGFR wild-type non-small cell lung cancer

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI), such as Erlotinib, have demonstrated remarkable efficacy in the treatment of non-small cell lung cancer (NSCLC) patients with mutated EGFR. However, the efficacy of EGFR-TKIs in wild-type (wt) EGFR tumours has been shown to be marginal. Methods that can sensitize Erlotinib to EGFR wild-type NSCLC remain rare. Herein, we developed a multifunctional superparamagnetic nanotheranostic agent as a novel strategy to potentiate Erlotinib to EGFR-wt NSCLCs. Our results demonstrate that the nanoparticles can co-escort Erlotinib and a vascular epithermal growth factor (VEGF) inhibitor, Bevacizumab (Bev), to EGFR-wt tumours. The nanotheranostic agent exhibits remarkable effects as an inhibitor of EGFR-wt tumour growth. Moreover, Bev normalizes the tumour embedded vessels, further promoting the therapeutic efficacy of Erlotinib. In addition, the tumour engagement of the nanoparticles and the vascular normalization could be tracked by magnetic resonance imaging (MRI). Collectively, our study, for the first time, demonstrated that elaborated nanoparticles could be employed as a robust tool to potentiate Erlotinib to EGFR-wt NSCLC, paving the way for imaging-guided nanotheranostics for refractory NSCLCs expressing EGFR wild-type genes.

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A Erlotinib-based nanoagent shows remarkable efficacy to inhibit EGFR-wt NSCLCs.

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Erlotinib and Bevacizumab show synergistic effects in inhibit EGFR-wt NSCLC.

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MRI was used to track the tumour engagement of the Erlotinib-based nanoagent.

Potential benefit of osismertinib plus bevacizumab in leptomeningeal metastasis with EGFR mutant non-small-cell lung cancer

Background

EGFR-mutant non-small cell lung cancer (NSCLC) is prone to leptomeningeal metastasis (LM) after Tyrosine kinase inhibitors (TKIs) treatment. Our previous study suggested that osimertinib plus bevacizumab was safe and effective in LM from EGFR-mutant NSCLC. This study aimed to compare the efficacy of osimertinib plus bevacizumab with osimertinib in EGFR-mutant NSCLC patients with LM.

Methods

We retrospectively reviewed the data from 27 LM patients with EGFR-mutant NSCLC who received osimertinib with or without bevacizumab at the Second Affiliated Hospital of Nanchang University. Next, we investigated the antitumor efficacy of osimertinib plus bevacizumab in an LM xenograft model using the H1975 (EGFR exon20 T790M and exon21 L858R) cell line. We examined the ability of osimertinib plus bevacizumab compared with osimertinib to penetrate the blood–brain barrier (BBB) and explored the potential mechanism.

Results

Our retrospective study observed the improved survival of LM patients in osimertinib plus bevacizumab group. The median overall survival (OS) of the patients who received osimertinib and bevacizumab (n = 16) compared with osimertinib group (n = 11) was 18.0 months versus 13.7 months (log-rank test, p = 0.046, HR = 2.867, 95% CI 1.007–8.162). The median intracranial Progression-free Survival (iPFS) was 10.6 months versus 5.5 months (log-rank test, p = 0.037, HR = 3.401, 95% CI 1.079–10.720). In the LM xenograft model with H1975 cells, the combined treatment significantly increased the effective intracranial concentration of osimertinib, modulated the level of E-cadherin and downregulated the levels of EGFR and downstream signaling pathways including p-AKT and reduced tumor microvessel density (TMD), indicated that combined osimertinib with bevacizumab may exhibit a synergistic effect in EGFR-mutant LM model possibly by modulating the level of E-cadherin.

Conclusions

Our findings indicate the potential benefit of osimertinib plus bevacizumab in LM with EGFR-mutant NSCLC, and more larger sample size research are still needed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03331-9.

Programmed death ligand 1 signals in cancer cells

The paradigm of surface-expressed programmed death ligand 1 (PDL1) signalling to immune cell programmed death 1 (PD1) to inhibit antitumour immunity has helped to develop effective and revolutionary immunotherapies using antibodies blocking these cell-extrinsic interactions. The recent discovery of cancer cell-intrinsic PDL1 signals has broadened understanding of pathologic tumour PDL1 signal consequences that now includes control of tumour growth and survival pathways, stemness, immune effects, DNA damage responses and gene expression regulation. Many such effects are PD1-independent. These insights demonstrate that the prevailing cell-extrinsic PDL1 signalling paradigm is useful, but incomplete in important respects. This Perspective discusses historical and recent advances in understanding cancer cell-intrinsic PDL1 signals, mechanisms for signal controls and important immunopathologic consequences including resistance to cytotoxic agents, targeted small molecules and immunotherapies. Cancer cell-intrinsic PDL1 signals present novel drug discovery targets and also have potential as reliable treatment response biomarkers. Cancer cell-intrinsic PD1 signals and cell-intrinsic PDL1 signals in non-cancer cells are discussed briefly, as are PDL1 signals from soluble and vesicle-bound PDL1 and PDL1 isoforms. We conclude with suggestions for addressing the most pressing challenges and opportunities in this rapidly developing field.

Ethoxy-erianin phosphate and afatinib synergistically inhibit liver tumor growth and angiogenesis via regulating VEGF and EGFR signaling pathways

The therapeutic efficacy of tyrosine kinase inhibitors (TKIs) on solid tumors is limited by drug resistance and side effects. Currently, the combination therapy comprises of TKIs and angiogenesis inhibitors have been corroborated as an effective approach in cancer therapy. Ethoxy-erianin phosphate (EBTP) is an anti-angiogenic compound with low toxicity obtained by structural modification of the natural product erianin. Here, we aimed to evaluate whether EBTP can cooperate with TKIs to inhibit the proliferation and angiogenesis of tumor cells and reduce toxic effects. First, CCK-8 results showed that EBTP can effectively inhibit the proliferation of liver cancer cell line HepG2. We combined EBTP with four TKIs (Bosutinib, Apatinib, Afatinib and Erlotinib) to treat HepG2 cells and CompuSyn software analysis suggested that EBTP/Afatinib(Afa)shows the best synergistic inhibitory effect. Meanwhile, EBTP/Afa can significantly suppress the proliferation, invasion, migration and angiogenesis of HepG2 and HUVECs. ELISA results revealed that EBTP/Afa inhibits the secretion of VEGF in HepG2. EBTP/Afa down-regulates the expression of VEGF, p-VEGFR1, p-VEGFR2 and p-EGFR in both HepG2 and HUVECs. Further, the supernatant of HepG2 cells treated with EBTP/Afa blocks the intracellular downstream signal transduction shared by VEGF and EGFR in HUVECs. Finally, EBTP/Afa significantly inhibits tumor growth and angiogenesis in vivo. To conclude, EBTP/Afa targets VEGF and EGFR signaling pathways in liver cancer cells and tumor vasculature, thereby inhibiting the proliferation, motion and angiogenesis of liver cancer cells. Overall, this study provides a new combined strategy for the clinical treatment of hepatocellular carcinoma.

Osimertinib Rechallenge With Bevacizumab vs. Chemotherapy Plus Bevacizumab in EGFR-Mutant NSCLC Patients With Osimertinib Resistance

At present, treatment options for osimertinib resistance are very limited. Dual inhibition of the vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) significantly improved the progression-free survival (PFS) of advanced EGFR-mutant non–small cell lung cancer (NSCLC). After EGFR-tyrosine kinase inhibitor (TKI) resistance, EGFR-TKI continuation combined with VEGF inhibitors still had clinical benefits. It is unclear whether the addition of bevacizumab after osimertinib progresses will prolong the duration of the osimertinib benefit. We screened 1289 patients with NSCLC and finally included 96 patients to evaluate osimertinib combined with bevacizumab (osi + bev) versus chemotherapy combined with bevacizumab (che + bev) for patients with acquired resistance to osimertinib. The overall response rate (ORR) for osi + bev and chem + bev was 15.8% (6 of 38) and 20.7% (12 of 58), respectively. The median PFS for osi + bev and che + bev was 7.0 and 4.9 months (HR 0.415 95%CI: 0.252–0.687 p = 0.001). The median OS for osi + bev and che + bev was 12.6 and 7.1 months (HR 0.430 95%CI: 0.266–0.696 p = 0.001). Multivariate analyses showed that no brain metastases and osi + bev treatment after osimertinib resistance correlated with longer PFS (p = 0.044, p = 0.001), while the median PFS of osimertinib less than 6 months (p = 0.021) had a detrimental effect on sequent treatment. Only osi + bev treatment was identified as an independent predictor of OS (p = 0.001). The most common adverse events (AEs) of grade ≥3 were hypertension (13.2%) and diarrhea (10.5%) in the osi + bevacizumab group. Neutropenia (24.1%) and thrombocytopenia (19%) were the most common grade ≥3 AEs in the che + bev group. The overall incidence of serious AEs (grade ≥3) was significantly higher in the chemotherapy plus bevacizumab group. Our study has shown the superiority of osi + bev compared to che + bev after the failure of osimertinib, making it a preferred option for patients with acquired resistance to osimertinib.

Novel Benzothiazole-Based Dual VEGFR-2/EGFR Inhibitors Targeting Breast and Liver Cancers: Synthesis, Cytotoxic Activity, QSAR and Molecular Docking Studies

A novel series of benzothiazole-based derivatives linked to various amino acids and their corresponding ethyl ester analogues were synthesized and were initially screened for their cytotoxic activity against human breast cancer cell line (MCF-7) and human liver carcinoma (HepG-2) and were further assessed as VEGFR-2 inhibitors. All the newly synthesized benzothiazole derivatives showed promising cytotoxic activities against the tested cell lines. Derivatives exhibited potent cytotoxic and VEGFR-2 inhibitory activities were then evaluated further as anticancer agents against the resistant triple-negative breast cancer (TNBC) cell line (MDA-MB-231) and as EGFR inhibitors. The carboxylic acid derivatives 10-12 and their ester analogues 21-23 displayed the highest anticancer activities with IC₅₀ of 0.73-0.89 µM, against MCF-7 and IC₅₀ of 2.54-2.80 µM, against HepG-2; compared to doxorubicin (IC₅₀ = 1.13 and 2.75 µM, respectively). In addition to their safety towards the normal cell line, the ethyl ester derivatives 21-23 showed a potent activity against the resistant MDA-MB-231 cell line with IC₅₀ of 5.45-7.28 µM, relative to doxorubicin (IC₅₀ = 7.46 µM) surpassing their carboxylic acid analogues 10-12 (IC₅₀ of 8.88-11.02 µM). Furthermore, the promising derivatives 10-12 and 21-23 displayed promising VEGFR-2 inhibitory activity (IC₅₀ = 0.15-0.19 µM) comparable to that of sorafenib (IC₅₀ = 0.12 µM). Against EGFR, the ethyl ester derivatives 21-23 showed superior inhibitory activity relative to the used reference standard, erlotinib, with IC₅₀ of 0.11-0.16 vs. 0.18 µM, respectively. The QSAR study revealed that the molecular bulkiness and molecular partial charge distribution govern the kinase inhibition potency in this series. Furthermore, the molecular docking study in VEGFR-2 active site showed that the newly synthesized benzothiazole derivatives adopted the common binding pattern of type II PK inhibitors.

Overall Treatment Strategy for Patients With Metastatic NSCLC With Activating EGFR Mutations

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (EGFR-TKIs) are standard of care in the first-line (1L) setting for patients with metastatic non-small cell lung cancer (mNSCLC) with activating EGFR mutations. EGFR-activating mutations are a predictive factor for response to EGFR-TKIs. Meta-analyses have shown that patients with exon 21_L858R mutations exhibit reduced sensitivity to EGFR-TKIs, resulting in inferior patient outcomes compared to those with exon 19 deletion mutations, with worse overall survival, progression-free survival, objective response, and disease control rates. Clinical activity observed with 1L therapy with first-generation (1G), second-generation (2G), and third-generation (3G) EGFR-TKIs is not permanent, and resistance inevitably develops in all cases, supporting the importance of overall treatment planning. The introduction of the 3G EGFR-TKI, osimertinib, provides an opportunity to overcome T790M-mediated resistance to 1G, and 2G EGFR-TKIs. Additionally, with the use of osimertinib, fewer T790M mutations are being detected as T790M is not a reported resistance mechanism to 3G EGFR-TKIs. However, there are currently no approved targeted therapies after 3G EGFR-TKIs. In order to further improve patient outcomes, there is a need to explore additional options for the overall treatment strategy for patients, including 1L and beyond. Combination of vascular endothelial growth factor (VEGF) inhibitors and EGFR-TKIs or chemotherapy and EGFR-TKIs may be a potential therapeutic approach in the 1L setting. This review discusses current treatment options for mNSCLC with activating EGFR mutations based on tumor, patient, and treatment characteristics and how an overall treatment plan may be developed.

Ramucirumab Plus Erlotinib Versus Placebo Plus Erlotinib in Patients With Untreated Metastatic EGFR-Mutated NSCLC: RELAY Japanese Subset

Introduction

The phase 3 RELAY global study (NCT02411448) revealed significant improvement in progression-free survival (PFS) with ramucirumab plus erlotinib (RAM + ERL) compared with placebo plus ERL (PL + ERL) in untreated EGFR-mutated metastatic NSCLC (hazard ratio [HR] = 0.59 [95% confidence interval (CI): 0.46-0.76, p < 0.0001]). This prespecified analysis evaluates efficacy, safety, and postprogression EGFR T790M rates of RELAY patients enrolled in Japan.

Methods

Patients were randomized (1:1) to oral ERL (150 mg/d) plus intravenous RAM (10 mg/kg) or PL every 2 weeks. End points included PFS (primary), safety (secondary), and biomarker analyses (exploratory). Plasma samples collected at baseline and poststudy treatment discontinuation were evaluated for EGFR T790M mutations by next-generation sequencing.

Results

The Japanese subset included 211 of 449 (47.0%) RELAY patients (RAM + ERL, n = 106; PL + ERL, n = 105). Median PFS was 19.4 versus 11.2 months for RAM + ERL versus PL + ERL treatment (HR = 0.610 [0.431-0.864]) in the Japanese intent-to-treat population, 16.6 versus 12.5 months (HR = 0.701 [0.424-1.159]) in the EGFR exon 19 deletion subgroup, and 19.4 versus 10.9 months (HR = 0.514 [0.317-0.835]) in the EGFR exon 21 L858R subgroup, respectively. Adverse events of grade 3 or above with RAM + ERL included hypertension (24.8%, all grade 3) and dermatitis acneiform (23.8%). Postprogression treatment-emergent T790M rates were similar between arms (RAM + ERL: 47%, 9 of 19 patients; PL + ERL: 50%, 20 of 40 patients).

Conclusions

Clinically meaningful efficacy was observed with RAM + ERL versus PL + ERL in the RELAY Japanese subset, with no new safety concerns. Postprogression T790M rates were similar across treatment arms, indicating the addition of RAM did not affect the ERL-associated EGFR T790M rates at disease progression.

RELAY Subgroup Analyses by EGFR Ex19del and Ex21L858R Mutations for Ramucirumab Plus Erlotinib in Metastatic Non-Small Cell Lung Cancer

PURPOSE

In EGFR-mutated metastatic non-small cell lung cancer (NSCLC), outcomes from EGFR tyrosine kinase inhibitors have differed historically by mutation type present, with lower benefit reported in patients with ex21L858R versus ex19del mutations. We investigated if EGFR-activating mutation subtypes impact treatment outcomes in the phase III RELAY study. Associations between EGFR mutation type and preexisting co-occurring and treatment-emergent genetic alterations were also explored.

PATIENTS AND METHODS

Patients with metastatic NSCLC, an EGFR ex19del or ex21L858R mutation, and no central nervous system metastases were randomized (1:1) to erlotinib (150 mg/day) with either ramucirumab (10 mg/kg; RAM+ERL) or placebo (PBO+ERL), every 2 weeks, until RECIST v1.1-defined progression or unacceptable toxicity. The primary endpoint was progression-free survival (PFS). Secondary and exploratory endpoints included overall response rate (ORR), duration of response (DOR), PFS2, time-to-chemotherapy (TTCT), safety, and next-generation sequencing analyses.

RESULTS

Patients with ex19del and ex21L858R mutations had similar clinical characteristics and comutational profiles. One-year PFS rates for ex19del patients were 74% for RAM+ERL versus 54% for PBO+ERL; for ex21L858R rates were 70% (RAM+ERL) versus 47% (PBO+ERL). Similar treatment benefits (ORR, DOR, PFS2, and TTCT) were observed in RAM+ERL-treated patients with ex19del and ex21L858R. Baseline TP53 comutation was associated with superior outcomes for RAM+ERL in both ex19del and ex21L858R subgroups. EGFR T790M mutation rate at progression was similar between treatment arms and by mutation type.

CONCLUSIONS

RAM+ERL provided significant clinical benefit for both EGFR ex19del and ex21L858R NSCLC, supporting this regimen as suitable for patients with either of these EGFR mutation types.

Efficacy of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) combined with bevacizumab for advanced non-squamous non-small-cell lung cancer patients with gradual progression on EGFR-TKI treatment: A cohort study

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) significantly improve outcomes of patients with EGFR-mutated non-small-cell lung cancer (NSCLC). However, acquired resistance inevitably emerges and remains a major challenge. The present study aimed to evaluate the efficacy of EGFR-TKIs plus bevacizumab in advanced non-squamous NSCLC patients with gradual progression on EGFR-TKIs.Advanced non-squamous EGFR-mutated NSCLC patients with gradual progression on EGFR-TKIs were administered bevacizumab while EGFR-TKIs were continued until disease progression occurred. Tumor lesions were assessed, and blood samples were collected at the start of the combination treatment and every 6 weeks until disease progression.Among the 15 included patients, there were no grade 3 or higher adverse events (AEs). Partial response (PR) and stable disease (SD) were achieved in 1 and 13 patients, respectively, with an objective response rate (ORR) of 6.7% and a disease control rate (DCR) of 93.3%. The median progression-free survival 2 (PFS2), defined as the time from the initiation of combination treatment to disease progression, was 5.0 (95% confidence interval [CI]: 4.0-6.0) months. Additionally, Spearman correlation analysis revealed that PFS2 was positively correlated with the serum vascular endothelial growth factor (VEGF) level at baseline (r = 0.7212, P = .0234). Patients with high baseline serum VEGF levels showed a better median PFS2 than those with low baseline serum VEGF levels (5.5 months vs 3.6 months, P = .0333).EGFR-TKIs plus bevacizumab led to a durable prolongation of PFS in non-squamous NSCLC patients with gradual progression on EGFR-TKIs. This therapeutic regimen was well tolerated and could be a promising strategy for these patients. Serum VEGF could be a potential biomarker to predict a subset of patients who are likely to benefit from EGFR-TKIs combined with bevacizumab.

Rational Application of First-Line EGFR-TKIs Combined with Antiangiogenic Inhibitors in Advanced EGFR-Mutant Non-Small-Cell Lung Cancer: A Systematic Review and Meta-Analysis

Purpose

A meta-analysis of randomized controlled trials (RCTs) was conducted to compare the difference in efficacy and safety between epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) with antiangiogenic inhibitors (A + T) and EGFR-TKI monotherapy in patients with treatment-naïve advanced EGFR-mutant non-small-cell lung cancer (NSCLC).

Methods

PubMed, Embase, Web of Science, and Cochrane electronic databases were searched for relevant RCTs. Meeting abstracts were also reviewed to identify appropriate studies. The endpoints included progression-free survival (PFS), overall survival (OS), 1- and 2-year OS rates, objective response rate (ORR), and grade ≥ 3 adverse events. All pooled outcomes were expressed using hazard ratios (HRs) or relative risk ratios (RRs).

Results

Data were collected from six eligible RCTs, which included 1,244 participants (619 in the A + T group and 625 in the TKI alone group). PFS was significantly improved with A + T compared to TKI alone (HR = 0.60; P < 0.01) regardless of EGFR mutation types (exon 19 deletion or L858R) and brain metastasis status (with or without brain metastases). There was no significant difference in median OS between the A + T and TKI alone groups (HR = 0.933; P = 0.551) regardless of EGFR mutation type. The ORR for A + T combination therapy was significantly increased compared to TKI monotherapy in exon 19 deletion subgroups (RR = 0.774; P = 0.008). There was no difference in the positive rates of acquired T790M mutation between the two groups (RR = 0.967; P = 0.846). More patients in the TKI alone group received a variety of subsequent systemic treatments than those in the A + T group (RR = 0.881; P = 0.002).

Conclusion

Addition of antiangiogenic inhibitors to first-line EGFR-TKI therapy significantly reduced the risk of disease progression for patients with advanced EGFR-mutant NSCLC regardless of EGFR mutation type and brain metastasis status. The lack of OS benefit may be explained by differences in subsequent treatments rather than drug resistance mechanisms.

Ramucirumab or placebo plus erlotinib in EGFR-mutated, metastatic non-small-cell lung cancer: East Asian subset of RELAY

In the global phase III RELAY study, ramucirumab plus erlotinib (RAM + ERL) demonstrated superior progression-free survival (PFS) to placebo plus erlotinib (PL + ERL) in untreated patients with epidermal growth factor receptor (EGFR) mutation-positive metastatic non-small-cell lung cancer (NSCLC) (hazard ratio (HR) [95% CI]: 0.59 [0.46-0.76]). This prespecified analysis assessed RAM + ERL efficacy and safety in the RELAY subset enrolled in East Asia (Japan, Taiwan, South Korea, Hong Kong). Randomized (1:1) patients received oral ERL (150 mg/d) plus intravenous RAM (10 mg/kg) or PL Q2W. Primary endpoint was PFS (investigator-assessed). Key secondary endpoints included objective response rate (ORR), disease control rate (DCR), duration of response (DoR), overall survival (OS), and safety. Exploratory endpoints included biomarker analyses and time to second progression (PFS2). Median PFS was 19.4 vs 12.5 mo for RAM + ERL (n = 166) vs PL + ERL (n = 170) (HR: 0.636 [0.485-0.833]; P = .0009). The 1-y PFS rate was 72.4% vs 52.2%, respectively. PFS benefit was consistent in most subgroups, including by EGFR mutation (Ex19del, Ex21.L858R). ORR and DCR were similar in both arms, but median DoR was longer with RAM + ERL. OS and PFS2 were immature at data cut-off (censoring rates, 81.2%-84.3% and 64.1%-70.5%, respectively). Grade ≥ 3 treatment-emergent adverse events were more frequent with RAM + ERL (70.7%) than PL + ERL (49.4%). Adverse events leading to treatment discontinuation were similar in both arms (RAM + ERL, 13.3%; PL + ERL, 12.9%), as were post-progression EGFR T790M mutation rates (43%; 50%). With superior PFS over PL + ERL and safety consistent with the overall RELAY population, RAM + ERL is a viable treatment option for EGFR-mutated metastatic NSCLC in East Asia.

Cost-effectiveness analysis of adding ramucirumab to the first-line erlotinib treatment for untreated EGFR-mutated metastatic non-small cell lung cancer in China

OBJECTIVE

To investigate the cost-effectiveness of ramucirumab plus erlotinib compared with placebo plus erlotinib in the first-line setting for patients with EGFR-mutated metastatic non-small cell lung cancer (mNSCLC) from the Chinese healthcare system perspective.

DESIGN

A Markov model consisting of three health states using clinical survival data from the RELAY phase III randomised clinical trial, a lifetime horizon for costs and quality-adjusted life-years (QALYs) was constructed to analyse the cost-effectiveness of ramucirumab plus erlotinib. One-way and probabilistic sensitivity analyses were performed to evaluate the robustness of the model. Additional price reduction scenario analyses were performed.

SETTING

The Chinese healthcare system perspective.

PARTICIPANTS

A hypothetical Chinese cohort of patients with confirmed previously documented ex19del or Leu858Arg mutation stage IV NSCLC, and without known epidermal growth factor receptor (EGFR) Thr790Met mutation and central nervous system metastases.

INTERVENTIONS

Ramucirumab plus erlotinib versus placebo plus erlotinib.

PRIMARY OUTCOME MEASURE

Costs, QALYs, incremental cost-effectiveness ratio (ICER).

RESULTS

In base-case analysis, ramucirumab plus erlotinib yield an additional 4.21 QALYs at a cost of $540 590, resulting in an ICER of $128 302/QALY. In price reduction scenario analysis, the ICER ($65 227/QALY) was decreased significantly when the National Reimbursement Drug List (NRDL) negotiation was available for ramucirumab, and the ICER ($131 554/QALY) was increased slightly when the NRDL negotiation was unavailable for erlotinib. Sensitivity analyses demonstrated our results to be most sensitive to the unit cost of ramucirumab (10 mg/kg), and more than 52.1% reduction in the price of ramucirumab resulted in the ICER under the willingness-to-pay threshold set for affluent regions ($70 353/QALY).

CONCLUSIONS

Ramucirumab plus erlotinib is unlikely to be cost-effective for patients with untreated EGFR-mutated mNSCLC in China. Reducing the price of ramucirumab through the National Healthcare Security Administration negotiation was found to be the most realistic action to improve cost-effectiveness.

Ramucirumab plus erlotinib in patients with untreated, EGFR-mutated, advanced non-small-cell lung cancer (RELAY): a randomised, double-blind, placebo-controlled, phase 3 trial

BACKGROUND

Dual blockade of the EGFR and VEGF pathways in EGFR-mutated metastatic non-small-cell lung cancer (NSCLC) is supported by preclinical and clinical data, yet the approach is not widely implemented. RELAY assessed erlotinib, an EGFR tyrosine kinase inhibitor (TKI) standard of care, plus ramucirumab, a human IgG1 VEGFR2 antagonist, or placebo in patients with untreated EGFR-mutated metastatic NSCLC.

METHODS

This is a worldwide, double-blind, phase 3 trial done in 100 hospitals, clinics, and medical centres in 13 countries. Eligible patients were aged 18 years or older (20 years or older in Japan and Taiwan) at the time of study entry, had stage IV NSCLC, with an EGFR exon 19 deletion (ex19del) or exon 21 substitution (Leu858Arg) mutation, an Eastern Cooperative Oncology Group performance status of 0 or 1, and no CNS metastases. We randomly assigned eligible patients in a 1:1 ratio to receive oral erlotinib (150 mg/day) plus either intravenous ramucirumab (10 mg/kg) or matching placebo once every 2 weeks. Randomisation was done by an interactive web response system with a computer-generated sequence and stratified by sex, geographical region, EGFR mutation type, and EGFR testing method. The primary endpoint was investigator-assessed progression-free survival in the intention-to-treat population. Safety was assessed in all patients who received at least one dose of study treatment. This trial is registered at ClinicalTrials.gov, NCT02411448, and is ongoing for long-term survival follow-up.

FINDINGS

Between Jan 28, 2016, and Feb 1, 2018, 449 eligible patients were enrolled and randomly assigned to treatment with ramucirumab plus erlotinib (n=224) or placebo plus erlotinib (n=225). Median duration of follow-up was 20·7 months (IQR 15·8-27·2). At the time of primary analysis, progression-free survival was significantly longer in the ramucirumab plus erlotinib group (19·4 months [95% CI 15·4-21·6]) than in the placebo plus erlotinib group (12·4 months [11·0-13·5]), with a stratified hazard ratio of 0·59 (95% CI 0·46-0·76; p<0·0001). Grade 3-4 treatment-emergent adverse events were reported in 159 (72%) of 221 patients in the ramucirumab plus erlotinib group versus 121 (54%) of 225 in the placebo plus erlotinib group. The most common grade 3-4 treatment-emergent adverse events in the ramucirumab plus erlotinib group were hypertension (52 [24%]; grade 3 only) and dermatitis acneiform (33 [15%]), and in the placebo plus erlotinib group were dermatitis acneiform (20 [9%]) and increased alanine aminotransferase (17 [8%]). Treatment-emergent serious adverse events were reported in 65 (29%) of 221 patients in the ramucirumab plus erlotinib group and 47 (21%) of 225 in the placebo plus erlotinib group. The most common serious adverse events of any grade in the ramucirumab plus erlotinib group were pneumonia (seven [3%]) and cellulitis and pneumothorax (four [2%], each); the most common in the placebo plus erlotinib group were pyrexia (four [2%]) and pneumothorax (three [1%]). One on-study treatment-related death due to an adverse event occurred (haemothorax after a thoracic drainage procedure for a pleural empyema) in the ramucirumab plus erlotinib group.

INTERPRETATION

Ramucirumab plus erlotinib demonstrated superior progression-free survival compared with placebo plus erlotinib in patients with untreated EGFR-mutated metastatic NSCLC. Safety was consistent with the safety profiles of the individual compounds in advanced lung cancer. The RELAY regimen is a viable new treatment option for the initial treatment of EGFR-mutated metastatic NSCLC.

FUNDING

Eli Lilly.

Correlation between the qualification for bevacizumab use and the survival of patients with non-small cell lung cancer harboring the epidermal growth factor receptor mutation: a retrospective analysis

PURPOSE

Previously, the combination of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) and bevacizumab (BEV) was investigated. A subgroup analysis of the IMpower150 trial, which investigated the combination of atezolizumab, carboplatin, paclitaxel, and bevacizumab (ABCP), demonstrated the benefit of ABCP in patients harboring EGFR mutations. This study aims to assess the prognostic significance of the qualification for BEV use and the proportion of patients who potentially benefit from BEV-containing combination therapy before and after initial EGFR-TKI treatment.

METHODS

We retrospectively analyzed the data of 297 patients with advanced or recurrent non-squamous non-small cell lung cancer (NSCLC) harboring EGFR mutations who had received EGFR-TKIs. We performed statistical analyses using the Kaplan-Meier method and the Cox regression adjusted for risk factors.

RESULTS

Of the 297 patients, 203 (68%) were eligible to receive BEV ("BEV fit") at the time of EGFR-TKI initiation. Among the "BEV unfit" patients at baseline (n = 70), 14 (20%) became eligible to receive ABCP ("ABCP fit") at the time of EGFR-TKI failure. The median overall survival (OS) of the "BEV fit" and "BEV unfit" patients was 26.2 [95% confidence interval (CI) 23.7-31.2] and 19.1 (95% CI 15.0-25.1) months, respectively (P < 0.001). The multivariate analysis revealed a marked correlation between survival and the qualification for BEV use.

CONCLUSIONS

The qualification for BEV use at baseline is independently related to the OS. Some patients harboring EGFR mutations, including those who were "BEV unfit" at baseline, could be eligible for the ABCP regimen after EGFR-TKI treatment.

Erlotinib plus either pazopanib or placebo in patients with previously treated advanced non-small cell lung cancer: A randomized, placebo-controlled phase 2 trial with correlated serum proteomic signatures

BACKGROUND

This study compared the efficacy and safety of treatment with erlotinib plus pazopanib versus erlotinib plus placebo in patients with previously treated advanced non-small cell lung cancer (NSCLC).

METHODS

Patients with progressive-stage IV NSCLC after either 1 or 2 previous chemotherapy regimens were randomized to receive erlotinib (150 mg by mouth daily) with either pazopanib (600 mg by mouth daily) or placebo. During treatment, patients were evaluated every 8 weeks until disease progression or unacceptable toxicity. After a study amendment, pretreatment serum specimens for the VeriStrat assay were collected. The predictive value of the VeriStrat score (good vs poor) for progression-free survival (PFS) and overall survival (OS) was assessed in the overall population and in each treatment group.

RESULTS

One hundred ninety-two eligible patients were randomized between February 2010 and February 2011. PFS was prolonged with erlotinib plus pazopanib versus erlotinib plus placebo (median, 2.6 vs 1.8 months; hazard ratio, 0.58; P = .001). There was no difference in the OS of the 2 groups. A good VeriStrat score predicted longer PFS and OS in the entire group and predicted longer PFS in the subgroup receiving erlotinib plus pazopanib. The addition of pazopanib increased toxicity, and this was consistent with the known toxicity profile.

CONCLUSIONS

The addition of pazopanib to erlotinib in an unselected group of patients with previously treated NSCLC improved PFS and increased treatment-related toxicity, but it had no influence on OS. The efficacy of both regimens was modest. Patients receiving erlotinib plus pazopanib had longer PFS if they had a good VeriStrat score versus a poor one. Cancer 2018;124:2355-64. © 2018 American Cancer Society.

Apatinib enhances antitumour activity of EGFR-TKIs in non-small cell lung cancer with EGFR-TKI resistance

BACKGROUND

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs)-rechallenged therapy for EGFR-mutant non-small cell lung cancer (NSCLC) patients who acquired resistance showed moderate efficacy. Considering the high interrelation between EGFR and vascular endothelial growth factor/vascular endothelial growth factor receptor (VEGF/VEGFR) pathways, we firstly evaluated EGFR-TKI combined with apatinib (a highly selective VEGFR2 inhibitor) in EGFR-TKI-resistant model and patients.

METHODS

Effects of apatinib, gefitinib and gefitinib plus apatinib were assessed on four NSCLC cell lines (A549 with wild-type EGFR, H1975 harbouring L858R and T790M, H1650 and HCC827 harbouring E746_A750 deletion) and xenograft model of acquired resistance that was established by injecting H1975 cells. Furthermore, we retrospectively evaluated EGFR-TKI rechallenge with apatinib in 16 patients.

RESULTS

Gefitinib plus apatinib strengthened the effect of gefitinib and apatinib alone on the four NSCLC cell lines, and H1975 was the most susceptible one. Co-administration delayed the tumour growth than mono-therapy in the xenograft model and had better effect on inhibiting the activation of EGFR and VEGFR2 and expression of CD31 (an angiogenesis marker) and vascular endothelial growth factor A (an important pro-angiogenesis factor in the tumour microenvironment). Changes in protein expression of protein kinase B/mammalian target of rapamycin and extracellular signal-regulated kinase pathways demonstrated the potent inhibitory effect on the pro-survival signalling pathways by combined therapy. EGFR-TKI rechallenge with apatinib achieved a median progression-free survival of 4.60 months (95% confidence interval, 2.23-12.52 months) in the patients.

CONCLUSIONS

Apatinib significantly potentiated the antitumour effect of gefitinib in NSCLC with T790M-related EGFR-TKI resistance both in vivo and vitro. EGFR-TKI rechallenge with apatinib might represent a new option for NSCLC with T790M or unknown resistance mechanism.

Antitumor activity and safety of combination therapy with the Toll-like receptor 9 agonist IMO-2055, erlotinib, and bevacizumab in advanced or metastatic non-small cell lung cancer patients who have progressed following chemotherapy

BACKGROUND

IMO-2055 is a Toll-like receptor 9 (TLR9) agonist that potentially enhances the efficacy of antitumor agents through immune stimulation. The objective of this phase Ib dose-escalation trial (3 + 3 design) was to determine the recommended phase II dose (RP2D) of IMO-2055 when combined with erlotinib and bevacizumab in patients with advanced non-small cell lung cancer (NSCLC).

METHODS

Patients with stage 3/4 NSCLC and progressive disease (PD) following chemotherapy received IMO-2055 0.08, 0.16, 0.32, or 0.48 mg/kg once weekly plus erlotinib 150 mg daily and bevacizumab 15 mg/kg every 3 weeks. Patients could receive treatment until PD or unacceptable toxicity.

RESULTS

Thirty-six patients were enrolled; 35 received at least one treatment dose. Two dose-limiting toxicities were observed across the dose range (Grade 3 dehydration and fatigue) with neither suggestive of a consistent toxicity pattern. IMO-2055 0.32 mg/kg was adopted as RP2D based on clinical and pharmacodynamic data. The most common treatment-emergent adverse events (TEAEs) were diarrhea (74 %), nausea (51 %), fatigue (51 %), rash (51 %), and injection-site reactions (49 %). Four patients experienced serious TEAEs considered to be study drug related. Five patients died, all due to PD. High-grade neutropenia and electrolyte disturbances previously reported with TLR9 agonists combined with platinum-based therapy were not observed in this study. Five of 33 patients evaluable for response (15 %) achieved partial response; another 20 (61 %) had stable disease, including 13 with stable disease ≥4 months.

CONCLUSIONS

IMO-2055 demonstrated good tolerability and possible antitumor activity in combination with erlotinib and bevacizumab in heavily pretreated patients with advanced NSCLC.

CXCL4L1-fibstatin cooperation inhibits tumor angiogenesis, lymphangiogenesis and metastasis

Anti-angiogenic and anti-lymphangiogenic drugs slow tumor progression and dissemination. However, an important difficulty is that a tumor reacts and compensates to obtain the blood supply needed for tumor growth and lymphatic vessels to escape to distant loci. Therefore, there is a growing consensus on the requirement of multiple anti-(lymph)angiogenic molecules to stop cell invasion efficiently. Here we studied the cooperation between endogenous anti-angiogenic molecules, endostatin and fibstatin, and a chemokine, the Platelet Factor-4 variant 1, CXCL4L1. Anti-angiogenic factors were co-expressed by IRES-based bicistronic vectors and their cooperation was analyzed either by local delivery following transduction of pancreatic adenocarcinoma cells with lentivectors, or by distant delivery resulting from intramuscular administration in vivo of adeno-associated virus derived vectors followed by tumor subcutaneous injection. In this study, fibstatin and CXCL4L1 cooperate to inhibit endothelial cell proliferation, migration and tubulogenesis in vitro. No synergistic effect was found for fibstatin-endostatin combination. Importantly, we demonstrated for the first time that fibstatin and CXCL4L1 not only inhibit in vivo angiogenesis, but also lymphangiogenesis and tumor spread to the lymph nodes, whereas no beneficial effect was found on tumor growth inhibition using molecule combinations compared to molecules alone. These data reveal the synergy of CXCL4L1 and fibstatin in inhibition of tumor angiogenesis, lymphangiogenesis and metastasis and highlight the potential of IRES-based vectors to develop anti-metastasis combined gene therapies.

Human Protein Reference Database and Human Proteinpedia as resources for phosphoproteome analysis

Human Protein Reference Database (HPRD) is a rich resource of experimentally proven features of human proteins. Protein information in HPRD includes protein-protein interactions, post-translational modifications, enzyme/substrate relationships, disease associations, tissue expression, and subcellular localization of human proteins. Although, protein-protein interaction data from HPRD has been widely used by the scientific community, its phosphoproteome data has not been exploited to its full potential. HPRD is one of the largest documentations of human phosphoproteins in the public domain. Currently, phosphorylation data in HPRD comprises of 95,016 phosphosites mapped on to 13,041 proteins. Additionally, enzyme-substrate reactions responsible for 5930 phosphorylation events were also documented. Significant improvements in technologies and high-throughput platforms in biomedical investigations led to an exponential increase of biological data and phosphoproteomic data in recent years. Human Proteinpedia, a community annotation portal developed by us, has also contributed to the significant increase in phosphoproteomic data in HPRD. A large number of phosphorylation events have been mapped on to reference sequences available in HPRD and Human Proteinpedia along with associated protein features. This will provide a platform for systems biology approaches to determine the role of protein phosphorylation in protein function, cell signaling, biological processes and their implication in human diseases. This review aims to provide a composite view of phosphoproteomic data pertaining to human proteins in HPRD and Human Proteinpedia.

Morphine-induced epidermal growth factor pathway activation in non-small cell lung cancer

BACKGROUND

Epidermal growth factor receptor (EGFR) is coactivated by the μ-opioid receptor (MOR), expressed on non-small cell lung cancer (NSCLC) cells and human lung cancer. We hypothesized that clinically used opioid analgesics that are MOR agonists coactivate EGFR, resulting in growth- and survival-promoting signaling.

METHODS

We used H2009, a human adenocarcinoma NSCLC cell line, with constitutive EGFR phosphorylation, which showed increased expression of MOR and the δ-opioid receptor by reverse transcriptase polymerase chain reaction. We used Western immunoblotting, magnetic bead-based Bio-Plex cytokine assay, immunofluorescent staining, BrdU incorporation enzyme-linked immunosorbent assay, and BioCoat™ Matrigel™ invasion assay to examine cell signaling, cytokine expression, colocalization of MOR and EGFR in human lung cancer, and cell proliferation and invasion, respectively.

RESULTS

Similar to epidermal growth factor (EGF), morphine stimulated phosphorylation of EGFR, Akt/protein kinase B (Akt), and mitogen-activated protein kinase/extracellular signal regulated kinase (MAPK/ERK) signaling in H2009 cells. Opioid receptor (OR) antagonist, naloxone, EGFR tyrosine kinase inhibitor, erlotinib, and silencing of MOR and δ-opioid receptor abrogated morphine- and EGF-induced phosphorylation of signaling, suggestive of OR-mediated coactivation of EGFR. H2009 cells secreted significantly higher levels of cytokines compared with control Beas2B epithelial cells. H2009-conditioned medium stimulated MOR expression in Beas2B cells, suggesting that cytokines secreted by H2009 may be associated with increased OR expression in H2009. We observed colocalization of EGFR and MOR, in human NSCLC tissue. Functionally, morphine- and EGF-induced proliferation and invasion of H2009 cells was ameliorated by naloxone as well as erlotinib.

CONCLUSION

Morphine-induced phosphorylation of EGFR occurs via ORs, leading to downstream MAPK/ERK, Akt phosphorylation, cell proliferation, and increased invasion. Notably, ORs are also associated with EGF-induced phosphorylation of EGFR. Increased coexpression of MOR and EGFR in human lung cancer suggests that morphine may have a growth-promoting effect in lung cancer.

Tailoring tyrosine kinase inhibitors to fit the lung cancer genome

Tyrosine kinase inhibitors (TKIs) have been in use as cancer therapeutics for nearly a decade, and their utility in targeting specific malignancies with defined genetic lesions has proven to be remarkably effective. Recent efforts to characterize the spectrum of genetic lesions found in non-small cell lung carcinoma (NSCLC) have provided important insights into the molecular basis of this disease and have also revealed a wide array of tyrosine kinases that might be effectively targeted for rationally designed therapies. The findings of these studies, however, also provide a cautionary tale about the limitations of single-agent therapies, which fail to account for the genetic heterogeneity and pathway redundancy that characterize advanced NSCLC. Emergence of drug resistance mechanisms to specific TKIs, such as gefitinib and erlotinib, suggests that more sophisticated chemotherapeutic paradigms that target multiple pathways at the same time will be required to effectively treat this disease.

Rapid and accurate ranking of binding affinities of epidermal growth factor receptor sequences with selected lung cancer drugs

The epidermal growth factor receptor (EGFR) is a major target for drugs in treating lung carcinoma. Mutations in the tyrosine kinase domain of EGFR commonly arise in human cancers, which can cause drug sensitivity or resistance by influencing the relative strengths of drug and ATP-binding. In this study, we investigate the binding affinities of two tyrosine kinase inhibitors--AEE788 and Gefitinib--to EGFR using molecular dynamics simulation. The interactions between these inhibitors and the EGFR kinase domain are analysed using multiple short (ensemble) simulations and the molecular mechanics/Poisson-Boltzmann solvent area (MM/PBSA) method. Here, we show that ensemble simulations correctly rank the binding affinities for these systems: we report the successful ranking of each drug binding to a variety of EGFR sequences and of the two drugs binding to a given sequence, using petascale computing resources, within a few days.

Fibroblast growth factor 2--a predictor of outcome for patients irradiated for stage II-III non-small-cell lung cancer

PURPOSE

The prognostic value of the tumor cell expression of the fibroblast growth factor 2 (FGF-2) in patients with non-small-cell lung cancer (NSCLC) is unclear. The present study investigated the effect of tumor cell expression of FGF-2 on the outcome of 60 patients irradiated for Stage II-III NSCLC.

METHODS AND MATERIALS

The effect of FGF-2 expression and 13 additional factors on locoregional control (LRC), metastasis-free survival (MFS), and overall survival (OS) were retrospectively evaluated. These additional factors included age, gender, Karnofsky performance status, histologic type, histologic grade, T and N category, American Joint Committee on Cancer stage, surgery, chemotherapy, pack-years, smoking during radiotherapy, and hemoglobin during radiotherapy. Locoregional failure was identified by endoscopy or computed tomography. Univariate analyses were performed with the Kaplan-Meier method and the Wilcoxon test and multivariate analyses with the Cox proportional hazard model.

RESULTS

On univariate analysis, improved LRC was associated with surgery (p = .017), greater hemoglobin levels (p = .036), and FGF-2 negativity (p <.001). On multivariate analysis of LRC, surgery (relative risk [RR], 2.44; p = .037), and FGF-2 expression (RR, 5.06; p <.001) maintained significance. On univariate analysis, improved MFS was associated with squamous cell carcinoma (p = .020), greater hemoglobin levels (p = .007), and FGF-2 negativity (p = .001). On multivariate analysis of MFS, the hemoglobin levels (RR, 2.65; p = .019) and FGF-2 expression (RR, 3.05; p = .004) were significant. On univariate analysis, improved OS was associated with a lower N category (p = .048), greater hemoglobin levels (p <.001), and FGF-2 negativity (p <.001). On multivariate analysis of OS, greater hemoglobin levels (RR, 4.62; p = .002) and FGF-2 expression (RR, 3.25; p = .002) maintained significance.

CONCLUSIONS

Tumor cell expression of FGF-2 appeared to be an independent negative predictor of LRC, MFS, and OS.

The role of anti-epidermal growth factor receptor and anti-vascular endothelial growth factor therapies in the treatment of non-small-cell lung cancer

Standard first-line therapy for non-small-cell lung cancer (NSCLC) with platinum-based agents, given in combination with cytotoxic compounds, has reached a relative plateau in its therapeutic efficacy. Novel molecular targeted agents acting on specific pathways have emerged as effective agents for treating NSCLC; some have already produced positive results in phase III trials. Notably, inhibition of the vascular endothelial growth factor (VEGF) pathway with an anti-VEGF antibody, bevacizumab, and targeting the epidermal growth factor receptor (EGFR) pathway with a small-molecule EGFR tyrosine kinase inhibitor erlotinib or a monoclonal antibody (cetuximab) have demonstrated prolonged survival in patients with advanced disease in both the first- and second-line settings. The heterogeneity of signaling processes leading to tumor cell survival and proliferation supports the targeting of multiple signaling pathways as an effective anticancer treatment strategy. Consequently, rational combinations of molecular targeted agents might offer superior clinical efficacy and an alternative treatment option to patients refractory to, or unable to tolerate, standard chemotherapy. The challenge lies in determining which molecular entities should be pursued and the best approach to combine them. This review discusses the potential clinical utility of combining bevacizumab and erlotinib to inhibit both angiogenesis and EGFR signaling as a valid nonchemotherapeutic approach for the treatment of NSCLC. Other combinations of novel therapies that block EGFR and angiogenic pathways, as well as complementary signaling pathways, with unique modes of action and low toxicity profiles could offer an increased repertoire of individualized treatment options for patients with advanced NSCLC.

Distinct growth factor-induced dynamic mass redistribution (DMR) profiles for monitoring oncogenic signaling pathways in various cancer cells

Targeting dysregulated signaling pathways in tumors has led to the development of a novel class of signal transduction inhibitors, including inhibitors of the epidermal growth factor (EGF) receptor (EGFR). To dissect oncogenic pathways, identify key pathway determinants, and evaluate the efficacy of targeted agents, it is vital to develop technologies that allow the detection of temporal signaling events under physiological conditions. Here we report the application of a label-free optical biosensor to reveal the rapid response of cancer cells to EGF, expressed as a dynamic mass redistribution (DMR) signal. In response to EGF, squamous cell carcinoma of the head and neck cells exhibited a rapid rise in DMR signal, whereas lung adenocarcinoma cells showed a biphasic DMR profile, suggesting a cell type-dependent DMR response. Pharmacological studies suggested the importance of EGFR and the phosphatidylinositol-3 kinase pathway in mediating the EGF-induced DMR response. The defined DMR signatures offer a simple yet sensitive tool for evaluating EGFR-targeted agents, as shown with gefitinib and erlotinib. The assay can also be used for cell-based high-throughput screening of EGF pathway inhibitors, as demonstrated by its robust performance in a 384-well plate format (Z' > 0.5). This technology is applicable to other oncogenic pathways for the discovery of novel therapeutic agents for the treatment of various cancers.

Combination of sunitinib, cetuximab and irradiation in an orthotopic head and neck cancer model

BACKGROUND

Recent preclinical and clinical studies indicate beneficial effects from combining radiotherapy with either anti-angiogenic drugs or anti-epidermal growth factor receptor (EGFR)-targeting agent. To investigate the effect of combining these approaches, we evaluated in vivo the antitumor efficacy of the anti-angiogenic compound sunitinib, an oral, multi-targeted tyrosine kinase inhibitor that inhibits among others vascular endothelial growth factor (VEGF) receptors-1, -2 and -3, cetuximab, a mAb targeting the EGFR, and irradiation (RT) given alone and in combination.

MATERIALS AND METHODS

Investigations were carried out using a VEGF-secreting human head and neck tumor cell line, CAL33, with a high EGFR content, growing as orthotopic xenografts in nude mice. Three days after tumor cell injection, sunitinib (20 mg/kg, p.o.), cetuximab (1 mg/kg, i.p.), both 5 days/week seven doses, and RT (6 Gy, 3 days/week, four doses) were administered alone and in combination during 9 days.

RESULTS

Concomitant administration of drugs produced a marked and significant supra-additive decrease, and the addition of RT completely abolished tumor growth. The drug association markedly reduced tumor cell proliferation (Ki67) and the number of the vessels, but enhanced cell differentiation.

CONCLUSION

The efficacy of this combination of sunitinib, cetuximab and RT may be of clinical importance in the management of head and neck cancer patients.

Histone deacetylase inhibitor romidepsin enhances anti-tumor effect of erlotinib in non-small cell lung cancer (NSCLC) cell lines

INTRODUCTION

Most epidermal growth factor receptor (EGFR) mutant non-small cell lung cancers (NSCLCs) are sensitive to EGFR tyrosine kinase inhibitors (TKIs) such as erlotinib or gefitinib, but many EGFR wild type NSCLCs are resistant to TKIs. In this study, we examined the effects of the histone deacetylase inhibitor, romidepsin, in combination with erlotinib, in NSCLC cell lines and xenografts.

METHODS

For in vitro studies, nine NSCLC cell lines with varying mutation status and histology were treated with erlotinib and romidepsin alone or in combination. 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assays were performed to determine the concentration that inhibits 50% (IC50) value of each drug or the combination. For in vivo studies, NCI-H1299 xenografts were inoculated subcutaneously into athymic nude mice. Romidepsin and/or erlotinib were injected intraperitoneally after tumors developed and tumor sizes were measured.

RESULTS

We found that romidepsin increased the sensitivity of erlotinib synergistically in all nine NSCLC cell lines including EGFR and KRAS wild type cell lines, KRAS mutant cell lines, and TKI resistant EGFR mutant cell lines. This effect was partially due to enhanced apoptosis. Furthermore, cotreatment of erlotinib and romidepsin inhibited NCI-H1299 xenograft growth in athymic nude mice.

CONCLUSIONS

These observations support a role for the combination of a histone deacetylase inhibitor and a TKI in the treatment of NSCLCs.

Combined vascular endothelial growth factor receptor and epidermal growth factor receptor (EGFR) blockade inhibits tumor growth in xenograft models of EGFR inhibitor resistance

PURPOSE

The epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) gefitinib and erlotinib benefit some non-small cell lung cancer (NSCLC) patients, but most do not respond (primary resistance) and those who initially respond eventually progress (acquired resistance). EGFR TKI resistance is not completely understood and has been associated with certain EGFR and K-RAS mutations and MET amplification.

EXPERIMENTAL DESIGN

We hypothesized that dual inhibition of the vascular endothelial growth factor (VEGF) and EGFR pathways may overcome primary and acquired resistance. We investigated the VEGF receptor/EGFR TKI vandetanib, and the combination of bevacizumab and erlotinib in vivo using xenograft models of EGFR TKI sensitivity, primary resistance, and three models of acquired resistance, including models with mutated K-RAS and secondary EGFR T790M mutation.

RESULTS

Vandetanib, gefitinib, and erlotinib had similar profiles of in vitro activity and caused sustained tumor regressions in vivo in the sensitive HCC827 model. In all four resistant models, vandetanib and bevacizumab/erlotinib were significantly more effective than erlotinib or gefitinib alone. Erlotinib resistance was associated with a rise in both host and tumor-derived VEGF but not EGFR secondary mutations in the KRAS mutant-bearing A549 xenografts. Dual inhibition reduced tumor endothelial proliferation compared with VEGF or EGFR blockade alone, suggesting that the enhanced activity of dual inhibition is due at least in part to antiendothelial effects.

CONCLUSION

These studies suggest that erlotinib resistance may be associated with a rise in both tumor cell and host stromal VEGF and that combined blockade of the VEGFR and EGFR pathways can abrogate primary or acquired resistance to EGFR TKIs. This approach merits further evaluation in NSCLC patients.

[Tumor vasculature as a therapeutic target in non-small cell lung cancer]

Despite developments in conventional (chemo)radiotherapy and surgery, survival of non-small cell lung cancer (NSCLC) patients remains poor. Treatments with targeted molecular drugs offer novel therapeutic strategies. Bevacizumab, a recombinant anti-vascular endothelial growth factor (VEGF) antibody, is the antiangiogenic drug at the most advanced stage of development in the therapy of NSCLC. However, a number of questions and future challenges relating to the use of bevacizumab in NSCLC remain. Furthermore, novel agents targeting the pre-existing NSCLC vasculature (i.e. vascular disrupting agents, VDAs) or multiple tyrosine kinase inhibitors have emerged as unique drug classes delivering promising results in several preclinical and clinical studies. Herein, we review the most recent data using these novel targeted agents either alone or in combination with chemotherapy in NSCLC.

EGFR Inhibition in the Treatment of Non-Small Cell Lung Cancer

Epidermal growth factor receptor (EGFR) inhibitors have introduced the concept of targeted therapy to the treatment of non-small cell lung cancer (NSCLC). These agents appear most effective in patients with tumors that are highly dependent on EGFR signaling pathways, a population that disproportionately includes females, nonsmokers, individuals of East Asian origin, and patients with adenocarcinoma histology. Currently available EGFR-inhibiting drugs include the tyrosine kinase inhibitors (TKIs) erlotinib, gefitinib, and lapatinib, which are administered orally and interfere with the intracellular tyrosine kinase domain, and the monoclonal antibodies (mAbs) cetuximab and panitumumab, which are administered intravenously and interfere with extracellular ligand binding. While the use of EGFR TKIs as monotherapy prolongs survival in metastatic NSCLC, they have demonstrated no benefit when added to conventional, cytotoxic chemotherapy. In contrast, the anti-EGFR mAb cetuximab appears most effective when combined with chemotherapy or radiation. Despite dramatic initial responses to treatment in some cases, NSCLC eventually becomes resistant to EGFR inhibition. Possible mechanisms include secondary mutations that interfere with drug binding, oncogenic pathways driven by other receptor tyrosine kinases, and independent activity of downstream signaling molecules. Efforts to overcome such resistance include irreversibly binding EGFR TKIs, multi-targeted TKIs, and combinations with chemotherapy, radiation, and other targeted therapies.

Fibroblast growth factor receptor-mediated signals contribute to the malignant phenotype of non-small cell lung cancer cells: therapeutic implications and synergism with epidermal growth factor receptor inhibition

Fibroblast growth factors (FGF) and their high-affinity receptors (FGFR) represent an extensive cellular growth and survival system. Aim of this study was to evaluate the contribution of FGF/FGFR-mediated signals to the malignant growth of non-small cell lung cancer (NSCLC) and to assess their potential as targets for therapeutic interventions. Multiple FGFR mRNA splice variants were coexpressed in NSCLC cells (n = 16) with predominance of FGFR1. Accordingly, both expression of a dominant-negative FGFR1 (dnFGFR1) IIIc-green fluorescent protein fusion protein and application of FGFR small-molecule inhibitors (SU5402 and PD166866) significantly reduced growth, survival, clonogenicity, and migratory potential of the majority of NSCLC cell lines. Moreover, dnFGFR1 expression completely blocked or at least significantly attenuated s.c. tumor formation of NSCLC cells in severe combined immunodeficient mice. Xenograft tumors expressing dnFGFR1 exhibited significantly reduced size and mitosis rate, enhanced cell death, and decreased tissue invasion. When FGFR inhibitors were combined with chemotherapy, antagonistic to synergistic in vitro anticancer activities were obtained depending on the application schedule. In contrast, simultaneous blockage of FGFR- and epidermal growth factor receptor-mediated signals exerted synergistic effects. In summary, FGFR-mediated signals in cooperation with those transmitted by epidermal growth factor receptor are involved in growth and survival of human NSCLC cells and should be considered as targets for combined therapeutic approaches.