A phase I trial of gefitinib and nimotuzumab in patients with advanced non-small cell lung cancer (NSCLC)

Vorinostat combined with brigatinib overcomes acquired resistance in EGFR-C797S-mutated lung cancer

The development of a new generation of tyrosine kinase inhibitors (TKIs) has improved the treatment response in lung adenocarcinomas. However, acquired resistance often occurs due to new epidermal growth factor receptor (EGFR) mutations. In particular, the C797S mutation confers drug resistance to T790M-targeting EGFR TKIs. To address C797S resistance, a promising therapeutic avenue is combination therapy that targets both total EGFR and acquired mutations to increase drug efficacy. We showed that combining vorinostat, a histone deacetylase inhibitor (HDACi), with brigatinib, a TKI, enhanced antitumor effects in primary culture and cell lines of lung adenocarcinomas harboring EGFR L858R/T790M/C797S mutations (EGFR-3M). While EGFR phosphorylation was decreased by brigatinib, vorinostat reduced total EGFR-3M (L858R/T790M/C797S) proteins through STUB1-mediated ubiquitination and degradation. STUB1 preferably ubiquitinated other EGFR mutants and facilitated protein turnover compared to EGFR-WT. The association between EGFR and STUB1 required the functional chaperone-binding domain of STUB1 and was further enhanced by vorinostat. Finally, STUB1 levels modulated EGFR downstream functions. Low STUB1 expression was associated with significantly poorer overall survival than high STUB1 expression in patients harboring mutant EGFR. Vorinostat combined with brigatinib significantly improved EGFR-TKI sensitivity to EGFR C797S by inducing EGFR-dependent cell death and may be a promising therapy in treating C797S-resistant lung adenocarcinomas.

CALM1 promotes progression and dampens chemosensitivity to EGFR inhibitor in esophageal squamous cell carcinoma

Background

Calmodulin1 (CALM1) has been identified as one of the overexpression genes in a variety of cancers and EGFR inhibitor have been widely used in clinical treatment but it is unknown whether CALM1 and epidermal growth factor receptor (EGFR) have a synergistic effect in esophageal squamous cell carcinoma (ESCC). The aim of the present study was to explore the synergistic effects of knock-out CALM1 combined with EGFR inhibitor (Afatinib) and to elucidate the role of CALM1 in sensitizing the resistance to Afatinib in ESCC.

Method

Immunohistochemistry (IHC) and qRT-PCR were used to examine the expression of CALM1 and EGFR in ESCC tissues. Kaplan–Meier survival analysis was used to analyze the clinical and prognostic significance of CALM1 and EGFR expression in ESCC. Furthermore, to evaluate the biological function of CALM1 in ESCC, the latest gene editing technique CRISPR/Cas9(Clustered regularly interspaced short palindromic repeats)was applied to knockout CALM1 in ESCC cell lines KYSE150, Eca109 and TE-1. MTT, flow cytometry, Transwell migration, scratch wound-healing and colony formation assays were performed to assay the combined effect of knock-out CALM1 and EGFR inhibitor on ESCC cell proliferation and migration. In addition, nude mice xenograft model was used to observe the synergistic inhibition of knock-out CALM1 and Afatinib.

Results

Both CALM1 and EGFR were found to be significantly over-expressed in ESCC compared with paired normal control. Over-expressed CALM1 and EGFR were significantly associated with clinical stage, T classification and poor overall prognosis, respectively. In vitro, the combined effect of knock-out CALM1 mediated by the lentivirus and EGFR inhibitor was shown to be capable of inhibiting the proliferation, inducing cell cycle arrest at G1/S stage and increasing apoptosis of KYSE-150 and Eca109 cells; invasion and migration were also suppressed. In vivo, the results of tumor weight and total fluorescence were markedly reduced compared with the sgCtrl-infected group and sgCAML1 group.

Conclusion

Our data demonstrated that knock-out of CALM1 could sensitize ESCC cells to EGFR inhibitor, and it may exert oncogenic role via promotion of EMT. Taken together, CALM1 may be a tempting target to overcome Afatinib resistance.

Trial Watch: Tumor-targeting monoclonal antibodies in cancer therapy

In 1997, for the first time in history, a monoclonal antibody (mAb), i.e., the chimeric anti-CD20 molecule rituximab, was approved by the US Food and Drug Administration for use in cancer patients. Since then, the panel of mAbs that are approved by international regulatory agencies for the treatment of hematopoietic and solid malignancies has not stopped to expand, nowadays encompassing a stunning amount of 15 distinct molecules. This therapeutic armamentarium includes mAbs that target tumor-associated antigens, as well as molecules that interfere with tumor-stroma interactions or exert direct immunostimulatory effects. These three classes of mAbs exert antineoplastic activity via distinct mechanisms, which may or may not involve immune effectors other than the mAbs themselves. In previous issues of OncoImmunology, we provided a brief scientific background to the use of mAbs, all types confounded, in cancer therapy, and discussed the results of recent clinical trials investigating the safety and efficacy of this approach. Here, we focus on mAbs that primarily target malignant cells or their interactions with stromal components, as opposed to mAbs that mediate antineoplastic effects by activating the immune system. In particular, we discuss relevant clinical findings that have been published during the last 13 months as well as clinical trials that have been launched in the same period to investigate the therapeutic profile of hitherto investigational tumor-targeting mAbs.

A Review of Monoclonal Antibody-Based Treatments in Non-small Cell Lung Cancer

Non-small cell lung cancer (NSCLC) is one of the most common types of lung cancer worldwide. It metastasizes rapidly and has a poor prognosis. The first-line treatment for most patients is a combination of chemotherapy and radiation. In many subjects, using targeted treatments alongside chemoradiation has shown a better outcome in terms of progression and quality of life for patients. These targeted treatments include small biological inhibiting molecules and monoclonal antibodies. In this review, we have assessed studies focused upon the treatment of non-small cell lung cancer. Some therapies are approved, such as bevacizumab and atezolizumab, while some are still in clinical trials, such as ficlatuzumab and ipilimumab, and others have been rejected due to inadequate disease control, such as figitumumab.

Targeting Epidermal Growth Factor Receptor in Non-Small-Cell-Lung Cancer: Current State and Future Perspective

BACKGROUND

Lung cancer is one of the leading cause of cancer death worldwide, the most common histological type of lung cancer is non-small cell lung cancer (NSCLC), whose occurrence and development is closely related to the mutation and amplification of epidermal growth factor receptors (EGFR). Currently , a series of targeted drugs were developed on the inhibition of EGFR such as epidermal growth factor receptortyrosine kinase inhibitor EGFR-TKI and monoclonal antibody (McAb).

OBJECTIVE

We sought to summarizes the current drugs targeting Epidermal Growth Factor Receptor in nonsmall- cell-lung.

METHODS

We conducted a comprehensive review of the development and application of EGFR-TKI and McAb which targeted EGFR in NSCLC and compared the mechanisms of PROTAC with the traditional inhibitors.

RESULTS

The drugs targeted EGFR in NSCLC have been widely used in clinic practices. Compared to traditional chemotherapy, these drugs excel with their clear and specific targeting, better curative effects, and less toxic and side effects. However, the mechanism comes with some insurmountable weaknesses like serious toxic and other side effects, as well as proneness to producing drug resistance.

CONCLUSION

The emerging PROTAC (Proteolysis Targeting Chimera) technology has been successfully applied to selective degradation of multiple protein targets, including EGFR. It also highlights the potential and challenges of PROTAC therapy regarding future combination therapeutic options in NSCLC treatment.

An EGFR-targeting antibody-drug conjugate LR004-VC-MMAE: potential in esophageal squamous cell carcinoma and other malignancies

Epidermal growth factor receptor (EGFR) is a rational target for cancer therapy, because its overexpression plays an important oncogenic role in a variety of solid tumors; however, EGFR‐targeted antibody–drug conjugate (ADC) therapy for esophageal squamous cell carcinoma (ESCC) is exceedingly rare. LR004 is a novel anti‐EGFR antibody with the advantages of improved safety and fewer hypersensitivity reactions. It may be of great value as a carrier in ADCs with high binding affinity and internalization ability. Here, we prepared an EGFR‐targeting ADC, LR004‐VC‐MMAE, and evaluated its antitumor activities against ESCC and EGFR‐positive cells. LR004 was covalently conjugated with monomethyl auristatin E (MMAE) via a VC linker by antibody interchain disulfide bond reduction. VC‐MMAE was conjugated with LR004 with approximately 4.0 MMAE molecules per ADC. LR004‐VC‐MMAE showed a potent antitumor effect against ESCC and other EGFR‐positive cells with IC₅₀ values of nM concentrations in vitro. The in vivo antitumor effects of LR004‐VC‐MMAE were investigated in ESCC KYSE520 and A431 xenograft nude mice models. Significant activity was seen at 5 mg·kg⁻¹, and complete tumor regression was observed at 15 mg·kg⁻¹ in the KYSE520 xenograft nude mice after four injections, while the naked antibody LR004 had little effect on inhibiting tumor growth. Similar promising results were obtained in the A431 models. In addition, the tumors also remained responsive to LR004‐VC‐MMAE for large tumor experiments (tumor volume 400–500 mm³). The study results demonstrated that LR004‐VC‐MMAE could be a potential therapeutic agent for ESCC and other EGFR‐expressing malignancies. We also evaluated PK profile of LR004‐VC‐MMAE ADC in the mice model, which would provide qualitative guiding significance for the further research.

Combination Strategies Using EGFR-TKi in NSCLC Therapy: Learning from the Gap between Pre-Clinical Results and Clinical Outcomes

Although epidermal growth factor receptor (EGFR) inhibitors have been used to treat non-small cell lung cancer (NSCLC) for decades with great success in patients with EGFR mutations, acquired resistance inevitably occurs after long-term exposure. More recently, combination therapy has emerged as a promising strategy to overcome this issue. Several experiments have been carried out to evaluate the synergism of combination therapy both in vitro and in vivo. Additionally, many clinical studies have been carried out to investigate the feasibility of treatment with EGFR-tyrosine kinase inhibitors (TKi) combined with other NSCLC treatments, including radiotherapy, cytotoxic chemotherapies, targeted therapies, and emerging immunotherapies. However, a significant gap still exists when applying pre-clinical results to clinical scenarios, which hinders the development and use of these strategies. This article is a literature review analysing the rationalities and controversies in the transition from pre-clinical investigation to clinical practice associated with various combination strategies. It also highlights clues and challenges regarding future combination therapeutic options in NSCLC treatment.

Dosing de novo combinations of two targeted drugs: Towards a customized precision medicine approach to advanced cancers

Metastatic cancers harbor complex genomic alterations. Thus, monotherapies are often suboptimal. Individualized combinations are needed in order to attenuate resistance. To help inform selection of safe starting doses for novel, two-agent, targeted drug combinations, we identified clinical trials in adult oncology patients who received targeted drug doublets (PubMed, January 1, 2010 through December 31, 2013). The dose percentage was calculated for each drug: (safe dose in combination divided by single agent full dose) X 100. Additive dose percentage represented the sum of the dose percentage for each drug. A total of 144 studies (N = 8568 patients; 95 combinations) were analyzed. In 51% of trials, each of the two drugs could be administered at 100% of their full dose. The lowest safe additive dose percentage was 60% if targets and/or class of drugs overlapped, or in the presence of mTor inhibitors, which sometimes compromised the combination dose. If neither class nor target overlapped and if mTor inhibitors were absent, the lowest safe additive dose percentage was 143%. The current observations contribute to the knowledge base that informs safe starting doses for new combinations of targeted drugs in the context of clinical trials or practice, hence facilitating customized combination therapies.

A randomized, phase II study of gefitinib alone versus nimotuzumab plus gefitinib after platinum-based chemotherapy in advanced non-small cell lung cancer (KCSG LU12-01)

We aimed to evaluate the efficacy of dual inhibition of epidermal growth factor receptor (EGFR) with nimotuzumab (EGFR monoclonal antibody) plus gefitinib (EGFR-tyrosine kinase inhibitor) in advanced non-small cell lung cancer (NSCLC) after platinum-based chemotherapy. An open label, randomized, phase II trial was conducted at 6 centers; 160 patients were randomized (1:1) to either gefitinib alone or nimotuzumab (200 mg, i.v. weekly) plus gefitinib (250 mg p.o. daily) until disease progression or intolerable toxicity. The primary endpoint was progression-free survival (PFS) at 3 months. Of the total 160 enrolled patients, 155 (77: gefitinib, 78: nimotuzumab plus gefitinib) received at least one dose and could be evaluated for efficacy and toxicity. The majority had adenocarcinoma (65.2%) and ECOG performance status of 0 to 1 (83.5%). The median follow-up was 22.1 months, and the PFS rate at 3 months was 48.1% in gefitinib and 37.2% in nimotuzumab plus gefitinib (P = not significant, NS). The median PFS and OS were 2.8 and 13.2 months in gefitinib and 2.0 and 14.0 months in nimotuzumab plus gefitinib. Combined treatment was not associated with superior PFS to gefitinib alone in patients with EGFR mutation (13.5 vs. 10.2 months in gefitinib alone, P=NS) or those with wild-type EGFR (0.9 vs. 2.0 months in gefitinib alone, P=NS). Combined treatment did not increase EGFR inhibition-related adverse events with manageable toxicities. The dual inhibition of EGFR with nimotuzumab plus gefitinib was not associated with better outcomes than gefitinib alone as a second-line treatment of advanced NSCLC (NCT01498562).

Cardiotoxicity of ErbB2-targeted therapies and its impact on drug development, a spotlight on trastuzumab

INTRODUCTION

Trastuzumab, a therapeutic monoclonal antibody directed against ErbB2, is often noted as a successful example of targeted therapy. Trastuzumab improved outcomes for many patients with ErbB2-positive breast and gastric cancers, however, cardiac side effects [e.g., left ventricular dysfunction and congestive heart failure (CHF)] were reported in the early phase clinical studies. This finding, subsequently corroborated by multiple clinical studies, raised concerns that the observed cardiotoxicity induced by trastuzumab might adversely impact the clinical development of other therapeutics targeting ErbB family members. Areas covered: In this review we summarize both basic research and clinical findings regarding trastuzumab-induced cardiotoxicity and assess if there has been an impact of trastuzumab-induced cardiotoxicity on the development of other agents targeting ErbB family members. Expert opinion: There are a number of scientific gaps that are critically important to address for the continued success of HER2-targeted agents. These include: 1) elucidating the molecular mechanisms contributing to cardiotoxicity; 2) developing relevant preclinical testing systems for predicting cardiotoxicity; 3) developing clinical strategies to identify patients at risk of cardiotoxicity; and 4) enhancing management of clinical symptoms of cardiotoxicity.

Targeted therapies for the treatment of non-small-cell lung cancer: Monoclonal antibodies and biological inhibitors

The usual treatments for patients with non-small-cell lung cancer (NSCLC), such as advanced lung adenocarcinoma, are unspecific and aggressive, and include lung resection, radiotherapy and chemotherapy. Recently, treatment with monoclonal antibodies and biological inhibitors has emerged as an effective alternative, generating effective results with few side effects. In recent years, several clinical trials using monoclonal antibodies presented potential benefits to NSCLC, and 4 of them are already approved for the treatment of NSCLC, such as cetuximab, bevacizumab, nivolumab and pembrolizumab. Also, biological inhibitors are attractive tolls for biological applications. Among the approved inhibitors are crizotinib, erlotinib, afatinib and gefitinib, and side effects are usually mild to intense. Nevertheless, biological molecule treatments are under development, and several new monoclonal antibodies and biological inhibitors are in trial to treat NSCLC. Also under trial study are as follows: anti-epidermal growth factor receptor (EGFR) antibodies (nimotuzumab and ficlatuzumab), anti-IGF 1 receptor (IGF-1R) monoclonal antibody (figitumumab), anti-NR-LU-10 monoclonal antibody (nofetumomab) as well as antibodies directly affecting the cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) molecule (ipilimumab and tremelimumab), to receptor activator of nuclear factor-kappa B ligand (RANKL) (denosumab) or to polymerase enzyme (veliparib and olaparib). Among new inhibitors under investigation are poly-ADP ribose polymerase (PARP) inhibitors (veliparib and olaparib) and phosphatidylinositol 3-kinase (PI3K) inhibitor (buparlisib). However, the success of immunotherapies still requires extensive research and additional controlled trials to evaluate the long-term benefits and side effects.

Emerging drugs for squamous cell lung cancer

INTRODUCTION

The management of advanced NSCLC has been shifted by histology-driven treatment and molecularly targeted therapy, especially in lung adenocarcinoma. However, as the second most common histology in NSCLC, the treatment options for squamous cell lung cancer (SQCLC) remain very limited.

AREAS COVERED

The review first discusses the role of histology in management of NSCLC and new cytotoxic agents in SQCLC, and then addresses genomic characterization and potential molecular targets in SQCLC. The article then provides an overview for several major categories of novel molecularly targeted therapies and immune-based strategies with particular attention to ongoing SQCLC trials.

EXPERT OPINION

The key challenges in drug development are to uncover novel actionable targets and to identify predictive biomarkers. Progress in genomic analysis has identified some promising targetable genes and oncogenic pathways in SQCLC with a wave of targeted agents being tested in clinical trials. Immunotherapy has also raised great interest in management of SQCLC, especially agents targeting immune check points, cytotoxic T-lymphocyte antigen-4, programmed death-1 receptor and its ligands. Better understanding of tumor biology and development of novel targeted therapies will help to facilitate more effective personalized therapy for patients with this devastating illness.

New treatment strategy for patients with EGFR-mutant lung cancer

SUMMARY Activating EGFR mutations in non-small-cell lung cancer were discovered in 2004. Patients harboring these mutations, who have been treated with EGFR–tyrosine kinase inhibitor (TKI), are expected to live longer than 2 years. However, lung cancer eventually progresses and the patients die of the disease. Thus, alternative treatments are needed for EGFR-mutated lung cancer. Here, we review the alternative treatments for patients with activating EGFR mutation. Combinations of available EGFR–TKIs (gefitinib or erlotinib) with chemotherapy and newer EGFR–TKIs (second-generation or third-generation EGFR–TKIs) have been developed as treatments for obtaining a more durable response or overcoming the acquired resistance to current EGFR–TKIs. In addition, new drugs other than EGFR–TKIs have also been developed. Their targets include EGFR itself and downstream signals of EGFR pathway, among others. However, these therapies cannot reach clinically striking effects so far. Greater efforts are needed to achieve an increased response, overcome resistance and prolong overall survival.

Targeted therapies in non-small cell lung carcinoma: what have we achieved so far?

The search for innovative therapeutic agents in non-small cell lung cancer (NSCLC) has witnessed a swift evolution. The number of targeted drugs that can improve patient outcomes with an acceptable safety profile is steadily increasing. In this review, we highlight current drugs that have already been approved or are under evaluation for the treatment of patients with NSCLC, either in monotherapy or combined therapy for both the first- and second-line settings. Experience with drugs targeting the vascular endothelial growth factor and its receptor, as well as the epidermal growth factor receptor is summarized. Moreover, we provide an overview of more novel targets in NSCLC and initial experience with the respective therapeutic agents.