Current and future targeted therapies for non-small-cell lung cancers with aberrant EGF receptors

An Inside Job: Applications of Intracellular Single Domain Antibodies

Sera of camelid species contain a special kind of antibody that consists only of heavy chains. The variable antigen binding domain of these heavy chain antibodies can be expressed as a separate entity, called a single domain antibody that is characterized by its small size, high solubility and oftentimes exceptional stability. Because of this, most single domain antibodies fold correctly when expressed in the reducing environment of the cytoplasm, and thereby retain their antigen binding specificity. Single domain antibodies can thus be used to target a broad range of intracellular proteins. Such intracellular single domain antibodies are also known as intrabodies, and have proven to be highly useful tools for basic research by allowing visualization, disruption and even targeted degradation of intracellular proteins. Furthermore, intrabodies can be used to uncover prospective new therapeutic targets and have the potential to be applied in therapeutic settings in the future. In this review we provide a brief overview of recent advances in the field of intracellular single domain antibodies, focusing on their use as research tools and potential therapeutic applications. Special attention is given to the available methods that allow delivery of single domain antibodies into cells.

Genotype Driven Therapy for Non-Small Cell Lung Cancer: Resistance, Pan Inhibitors and Immunotherapy

Eighty-five percent of patients with lung cancer present with Non-small Cell Lung Cancer (NSCLC). Targeted therapy approaches are promising treatments for lung cancer. However, despite the development of targeted therapies using Tyrosine Kinase Inhibitors (TKI) as well as monoclonal antibodies, the five-year relative survival rate for lung cancer patients is still only 18%, and patients inevitably become resistant to therapy. Mutations in Kirsten Ras Sarcoma viral homolog (KRAS) and epidermal growth factor receptor (EGFR) are the two most common genetic events in lung adenocarcinoma; they account for 25% and 20% of cases, respectively. Anaplastic Lymphoma Kinase (ALK) is a transmembrane receptor tyrosine kinase, and ALK rearrangements are responsible for 3-7% of NSCLC, predominantly of the adenocarcinoma subtype, and occur in a mutually exclusive manner with KRAS and EGFR mutations. Among drug-resistant NSCLC patients, nearly half exhibit the T790M mutation in exon 20 of EGFR. This review focuses on some basic aspects of molecules involved in NSCLC, the development of resistance to treatments in NSCLC, and advances in lung cancer therapy in the past ten years. Some recent developments such as PD-1-PD-L1 checkpoint-based immunotherapy for NSCLC are also covered.

The top 100 cited articles in lung cancer - a bibliometric analysis

Aim of the study

To analyze the 100 most cited lung cancer articles published in biomedical literature in the last 44 years. We pointed out developments in lung cancer and aimed to create convenient access for the researchers of this dynamic field.

Material and methods

We accessed the WoS database (accessed: 15.07.2019) using the keyword “lung cancer” between 1975 and 2019. The top 100 cited articles were analyzed by topic, journal, author, year, institution, level of evidence, adjusted citation index and also the correlations between citation, adjusted citation index, impact factor and length of time since publication.

Results

A total of 240,701 eligible articles were identified and we chose the top 100 articles cited in the field of lung cancer. The mean number of citations for these articles was 1879.82 ±1264.78. The most cited article was (times cited: 7751) a study by Lynch et al. The New England Journal of Medicine (NEJM) made the greatest contribution to the top 100 list with 32 articles, and the most cited article also originated from NEJM. The highest number of citations was seen in 2017 with 18,393 citations while the highest number of publications was seen in 2005 with 12 publications.

Conclusions

Oncology is a developing field and we have seen the evolution in this area through the treatment of lung cancer in recent years. The first 100 articles in our analysis not only reflect the landmark articles with the greatest impact on lung cancer research, but also acknowledge the most productive authors and institutions that have contributed to the list with their articles.

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.

Cell-penetrable nanobodies (transbodies) that inhibit the tyrosine kinase activity of EGFR leading to the impediment of human lung adenocarcinoma cell motility and survival

Most patients suffering from non-small cell lung cancer (NSCLC) have epidermal growth factor receptor (EGFR) overexpression. Currently, EGFR tyrosine kinase inhibitors (TKIs) that act as the ATP-analogs and monoclonal antibodies (MAbs) to EGFR-ectodomain that block intracellular signaling are used for the treatment of advanced NSCLC. Unfortunately, adverse effects due to the TKI off-target and drug resistance occur in a significant number of the treated patients while some NSCLC genotypes do not respond to the therapeutic MAbs. Thus, a more effective remedy for the treatment of EGFR-overexpressed cancers is deemed necessary. In this study, VH/V_H H displayed-phage clones that are bound to recombinant EGFR-TK were fished-out from a humanized-camel VH/V_H H phage display library. VH/V_H H of three phage-infected Escherichia coli clones (VH18, V_H H35, and VH36) were linked molecularly to nonaarginine (R9) for making them cell penetrable. R9-VH18, R9-V_H H35, and R9-VH36 were cytotoxic to human adenocarcinomic alveolar basal epithelial cells (A549) at the fifty percent inhibitory concentration (IC₅₀ ) 0.181 ± 0.132, 0.00961 ± 0.00516, and 0.00996 ± 0.00752 μM, respectively, which were approximately 1000-fold more effective than small molecular TKIs. R9-VH18 and R9-VH36 also delayed cancer cell migration in a scratch-wound assay. Computerized homology modeling and intermolecular docking revealed that VH18 and V_H H35 used CDR3 to interact with EGFR-TK residues close to the catalytic site, which might sterically hinder the ATP-binding of the TK; VH36 used CDR2 to bind at the asymmetric dimerization surface, which might disrupt EGFR dimerization leading to inhibition of intracellular signaling. The humanized-cell penetrable nanobodies have a high potential for developing further towards a clinical application.

Concordance analysis between HER2 immunohistochemistry and in situ hybridization in non-small cell lung cancer

PURPOSE

This study aimed to elucidate the concordance between human epidermal growth factor receptor 2 (HER2) immunohistochemistry (IHC) and in situ hybridization (ISH) and the diagnostic accuracy of HER2 IHC in non-small cell lung cancer (NSCLC) through a meta-analysis and diagnostic test accuracy review.

METHODS

Seven eligible studies and 1,217 patients with NSCLC were included in the review. The concordance between HER2 IHC and ISH was analyzed. To confirm the diagnostic accuracy of HER2 IHC, the sensitivity and specificity were analyzed and the area under the curve (AUC) in the summary receiver operating characteristic (SROC) curve was calculated.

RESULTS

The concordance rate between HER2 IHC and ISH was 0.795 (95% confidence interval [CI] 0.534-0.929). In the HER2 IHC-negative (score 0/1+) subgroup, the concordance rate was 0.975 (95% CI 0.854-0.996). The concordance rates of the HER2 IHC score 2+ and 3+ subgroups were 0.091 (95% CI 0.039-0.197) and 0.665 (95% CI 0.446-0.830), respectively. In diagnostic test accuracy review, the pooled sensitivity and specificity were 0.67 (95% CI 0.54-0.78) and 0.89 (95% CI 0.87-0.91), respectively. The AUC in the SROC curve was 0.891 and the diagnostic odds ratio was 16.99 (95% CI 5.08-56.76).

CONCLUSIONS

HER2 IHC was largely in agreement with ISH in cases of HER2 IHC score 0/1+. Because the concordance rates of HER2 IHC score 2/3+ cases were lower than that of HER2 IHC score 0/1+ cases, further studies for detailed analysis criteria for HER2 IHC score 2+ or 3+ are required.

The peripheral blood neutrophil-to-lymphocyte ratio is a prognostic predictor for survival of EGFR-mutant nonsmall cell lung cancer patients treated with EGFR-TKIs

Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) are the standard first-line treatment for EGFR-mutant nonsmall cell lung cancer (NSCLC) patients. However, studies have reported that not all NSCLC patients harboring kinase domain mutations in epidermal growth factor receptor (EGFR) show significant clinical benefits from EGFR-targeted tyrosine kinase inhibitors (TKIs). Therefore, it is necessary to establish feasible biomarkers to predict the prognosis of EGFR-mutant NSCLC patients treated with EGFR-TKIs. This study aimed to determine biomarkers using inflammatory parameters from complete blood counts to predict the prognosis of EGFR-mutant NSCLC patients treated with EGFR-TKIs.We retrospectively investigated 127 stage IIIB/IV NSCLC patients with activating EGFR mutations who were treated with EGFR-TKIs. We used receiver operating characteristic (ROC) curves to determine the optimal cut-off for the inflammatory markers as prognostic factors. Additionally, univariate and multivariate analyses were used to identify prognostic factors for progression-free survival (PFS) and overall survival (OS) of EGFR-mutant NSCLC patients treated with EGFR-TKIs.The receiver operating characteristic analysis indicated that the lymphocyte-to-monocyte ratio (LMR) and neutrophil-to-lymphocyte ratio (NLR) cut-off values were 3.37 and 2.90, respectively. The univariate analysis showed that a high LMR (>3.37) and low NLR (≤2.90) were significantly correlated with long-term PFS and OS (LMR, P = .007; NLR, P < .001). The multivariate Cox regression analysis revealed that only low NLR was an independent prognostic factor for long-term PFS and OS (PFS, HR = 0.573, 95% CI: 0.340-0.964, P = .036; OS, HR = 0.491, 95% CI: 0.262-0.920, P = .026).The data show that a low NLR was a good prognostic factor in EGFR-mutant NSCLC patients receiving EGFR-TKIs treatment. Moreover, the NLR measurement has better prognostic value than LMR.

Lung cancer targeted therapy: Folate and transferrin dual targeted, glutathione responsive nanocarriers for the delivery of cisplatin

To achieve lung cancer targeted therapy, folic acid (FA) and transferrin (Tf) modified cisplatin (CDDP) loaded nanoparticles were applied for the in vitro and in vivo evaluation. The aim of this research was to develop FA modified SS bonds based prodrug of CDDP (namely FA-ss-CDDP) and Tf modified cystamine-oleic acid (Tf-ss-OA). Further, FA-ss-CDDP and Tf-ss-OA were used to prepare NPs, which could target the lung tumor cells through receptor-mediated pathways to increase the efficiency of CDDP. FA and Tf modified CDDP loaded NPs (FA/Tf-CDDP-NPs) were constructed. The physiochemical properties, in vitro drug release profiles, in vitro cytotoxicity, and in vivo biodistribution were investigated. The antitumor effect of self-assembed NPs was evaluated both in vitro and in vivo. FA/Tf-CDDP-NPs exhibited remarkably enhanced accumulation in tumor tissue and better tumor inhibition effect in vitro and in vivo. FA/Tf-CDDP-NPs displayed almost complete suppression of tumor growth with no obviously body weight change of the treated mice. The newly constructed NPs could successfully load drugs and showed better efficiency than free drug formula; and FA/TF could function as excellent targeting ligands to improve the cell targeting ability of the NPs. The resulting FA/Tf-CDDP-NPs offered a promising tumor therapy strategy for the treatment of lung cancer.

Redox-responsive and pH-sensitive nanoparticles enhanced stability and anticancer ability of erlotinib to treat lung cancer in vivo

Purpose

Erlotinib (ETB) is a well-established therapeutic for non-small-cell lung cancer (NSCLC). To overcome drug resistance and severe toxicities in the clinical application, redox-responsive and pH-sensitive nanoparticle drug delivery systems were designed for the encapsulation of ETB.

Methods

Poly(acrylic acid)-cystamine-oleic acid (PAA-ss-OA) was synthesized. PAA-ss-OA-modified ETB-loaded lipid nanoparticles (PAA-ETB-NPs) were prepared using the emulsification and solvent evaporation method. The tumor inhibition efficacy of PAA-ETB-NPs was compared with that of ETB-loaded lipid nanoparticles (ETB-NPs) and free ETB anticancer drugs in tumor-bearing mice.

Results

PAA-ETB-NPs had a size of 170 nm, with a zeta potential of −32 mV. The encapsulation efficiency and drug loading capacity of PAA-ETB-NPs were over 85% and 2.6%, respectively. In vitro cytotoxicity of ETB-NPs were higher than that of ETB solution. The cytotoxicity of PAA-ETB-NPs was the highest. The in vivo tumor growth inhibition by PAA-ETB-NP treatment was significantly higher than that by ETB-NPs and ETB solution. No obvious weight loss was observed in any of the treatment groups, indicating that all the treatments were well tolerated.

Conclusion

PAA-ETB-NPs could enhance the stability and anti-cancer ability of ETB to treat lung cancer and are a promising drug delivery system for lung cancer treatment.

A peptidomimetic with a chiral switch is an inhibitor of epidermal growth factor receptor heterodimerization

Among different types of EGFR dimers, EGFR-HER2 and HER2-HER3 are well known in different types of cancers. Targeting dimerization of EGFR will have a significant impact on cancer therapies. A symmetric peptidomimetic was designed to inhibit the protein-protein interaction of EGFR. The peptidomimetic (Cyclo(1,10)PpR (R) Anapa-FDDF-(R)-Anapa)R, compound 18) was shown to exhibit antiproliferative activity with an IC₅₀ of 194 nM in HER2-expressing breast cancer cell lines and 18 nM in lung cancer cell lines. The peptidomimetic has a Pro-Pro sequence in the structure to stabilize the β-turn and a β-amino acid, amino napthyl propionic acid. To investigate the effect of the chirality of β-amino acid on the structure of the peptide and its antiproliferative activity, diastereoisomers of compound 18 were designed and synthesized. Structure-activity relationships of these compounds indicated that there is a chiral switch at β-amino acid in the designed compound. The peptidomimetic with R configuration at β-amino acid and with a L-Pro-D-Pro sequence was the most active compound (18). Using enzyme complement fragmentation assay and proximity ligation assay, we show that compound 18 inhibits HER2:HER3 and EGFR:HER2 dimerization. Surface plasmon resonance studies suggested that compound 18 binds to the HER2 extracellular domain and in particular to domain IV. The anticancer activity of compound 18 was evaluated using a xenograft model of breast cancer in mice; compound 18 suppressed the tumor growth in mice compared to control. Compound 18 was also shown to have a synergistic effect with erlotinib on EGFR mutated lung cancer cell lines.

Preparation for the end of life and life completion during late-stage lung cancer: An exploratory analysis

Objective:

Our aim was to explore preparation for the end of life (EoL) and life closure among persons with advanced metastatic lung cancer. Understanding quality of life through the lens of preparation and completion is important since the trajectory of lung cancer can be relatively short, often leading to application of cancer-directed therapies near death without the opportunity for advance planning or palliative care. Clinical research is needed to understand the kinds of distress specific to older adults with advanced lung cancer that are amendable to palliative care interventions.

Method:

We employed an exploratory cross-sectional design to examine psychosocial and existential concerns among a purposive sample (N = 30) of advanced lung cancer patients using the “end-of-life preparation” and “life completion” subscales of the Quality of Life at the End of Life (QUAL–E) questionnaire. Nonparametric methods were employed to analyze preparation, completion, global quality of life (QoL), and the associations among depressive symptoms, preparation, completion, and global QoL.

Results:

Higher scores on life completion were associated with better global QoL, and with items related to transcendence, communicative acts, and interpersonal relationships demonstrating important contributions. The perception of being a future burden on family members was the greatest concern within the preparation domain. Depressive symptoms were not associated with preparation, completion, or global QoL.

Significance of Results:

Psychosocial and existential issues contribute to QoL at the EoL among older adults with late-stage lung cancer during cancer-directed therapy, concurrent care, and hospice. The role of preparation, especially self-perceived burden, merits further research early on in the oncological setting. The preparation and life completion subscales of the QUAL–E are feasible clinical tools for facilitating dyadic communication about sensitive topics in the palliative care setting.

Next-generation EGFR/HER tyrosine kinase inhibitors for the treatment of patients with non-small-cell lung cancer harboring EGFR mutations: a review of the evidence

Tyrosine kinase inhibitors (TKIs) against human epidermal growth factor receptor (EGFR/HER) family have been introduced into the clinic to treat cancers, particularly non-small-cell lung cancer (NSCLC). There have been three generations of the EGFR/HER-TKIs. First-generation EGFR/HER-TKIs, binding competitively and reversibly to the ATP-binding site of the EGFR TK domain, show a significant breakthrough treatment in selected NSCLC patients with activating EGFR mutations (actEGFRm) EGFR (L858R) and EGFR (Del19), in terms of safety, efficacy, and quality of life. However, all those responders inevitably develop acquired resistance within 12 months, because of the EGFR (T790M) mutation, which prevents TKI binding to ATP-pocket of EGFR by steric hindrance. The second-generation EGFR/HER-TKIs were developed to prolong and maintain more potent response as well as overcome the resistance to the first-generation EGFR/HER-TKIs. They are different from the first-generation EGFR/HER-TKIs by covalently binding to the ATP-binding site, irreversibly blocking enzymatic activation, and targeting EGFR/HER family members, including EGFR, HER2, and HER4. Preclinically, these compounds inhibit the enzymatic activation for actEGFRm, EGFR (T790M), and wtEGFR. The second-generation EGFR/HER-TKIs improve overall survival in cancer patients with actEGFRm in a modest way. However, they are not clinically active in overcoming EGFR (T790M) resistance, mainly because of dose-limiting toxicity due to simultaneous inhibition against wtEGFR. The third-generation EGFR/HER-TKIs selectively and irreversibly target EGFR (T790M) and actEGFRm while sparing wtEGFR. They yield promising efficacy in NSCLC patients with actEGFRm as well as EGFR (T790M) resistant to the first- and second-generation EGFR-TKIs. They also appear to have a lower incidence of toxicity due to the reduced inhibitory effect on wtEGFR. Currently, the first-generation EGFR/HER-TKIs gefitinib and erlotinib and second-generation EGFR/HER-TKI afatinib have been approved for use as the first-line treatment of metastatic NSCLC with actEGFRm. This review will summarize and evaluate a broad range of evidence of recent development of EGFR/HER-TKIs, with a focus on the second- and third-generation EGFR/HER-TKIs, in the treatment of patients with NSCLC harboring EGFR mutations.