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

First-line concomitant EGFR-TKI + chemotherapy versus EGFR-TKI alone for advanced EGFR-mutated NSCLC: a meta-analysis of randomized phase III trials

INTRODUCTION

A tyrosine-kinase inhibitor (TKI) is indicated as a first-line treatment for patients with non-small-cell lung cancer (NSCLC) harboring an epidermal growth-factor - receptor (EGFR) mutation. Chemotherapy (ChT) given in combination with an EGFR-TKI in this setting is of interest.

METHODS

We conducted a meta-analysis of phase III randomized trials comparing EGFR-TKI + ChT vs. EGFR-TKI alone as first-line therapy for advanced NSCLC harboring an activating EGFR mutation.

RESULTS

Three studies evaluated gefitinib + ChT (NEJ009, GAP-Brain, and Noronha et al.) and another evaluated osimertinib + ChT (FLAURA-2). Those four eligible studies included 1413 patients with non-squamous NSCLCs, 826 (58%) with an exon-19 deletion (ex19del) and 541 (38%) with EGFRL858R. The EGFR-TKI + ChT combination was significantly associated with prolonged PFS (hazard ratio [HR]: 0.52 [95% confidence interval (CI): 0.45-0.59]; p < 0.0001) and OS (HR: 0.69 [0.52-0.93]; p = 0.01). PFS was particularly improved for patients with brain metastases (HR: 0.41[0.33-0.51]; p < 0.00001).

CONCLUSIONS

For patients with untreated, advanced, EGFR-mutated NSCLCs, the EGFR-TKI + ChT combination, compared to EGFR-TKI alone, was associated with significantly prolonged PFS and OS. However, further studies are needed to identify which patients will benefit the most from the combination.

REGISTRATION

PROSPERO CRD42024508055.

Erianin promotes apoptosis and inhibits Akt-mediated aerobic glycolysis of cancer cells

Highly activated aerobic glycolysis provides the metabolic requirements for tumor cell growth and proliferation. Erianin, a natural product isolated from Dendrobium chrysotoxum Lindl, has been reported to exert antitumor activity in multiple cancers. However, whether Erianin exerts inhibitory effects on aerobic glycolysis and the inherent mechanism remain poorly defined in non-small cell lung cancer (NSCLC). Here, we showed that Erianin inhibited the cell viability and proliferation, and induced apoptosis in NSCLC cells. Moreover, Erianin overtly suppressed aerobic glycolysis via decreasing HK2 expression. Mechanistically, Erianin dose-dependently curbed the Akt-GSK3β signaling pathway phosphorylation activation, which afterwards downregulated HK2 expression. Meanwhile, Erianin inhibited HCC827 tumor growth in vivo. Taken together, our results suggest that the natural product Erianin can suppress aerobic glycolysis and exert potent anticancer effects via the Akt-GSK3β signaling pathway in NSCLC cells.

Co-delivery of PD-L1- and EGFR-targeting siRNAs by synthetic PEG12-KL4 peptide to the lungs as potential strategy against non-small cell lung cancer

BACKGROUND

Small interfering RNA (siRNA) holds great promise for treating various lung diseases, but the lack of safe and efficient pulmonary siRNA delivery systems has hindered its advance into the clinics. The epidermal growth factor receptor (EGFR) which promotes cell proliferation, and the programmed cell death ligand 1 (PD-L1) which plays a crucial role in suppressing cytotoxic T cells activity, are two important targets for treating non-small cell lung cancer (NSCLC). Here, we explored the potential of PEG12-KL4, a synthetic peptide, to deliver siRNA to various NSCLC cells and to lung tissues in mice.

METHODS

PEG12-KL4 was used to transfect siRNAs targeted at both EGFR and PD-L1 into NSCLC cells. Immunoblotting was used to evaluate the siRNA silencing effects in HCC827 and NCI-H1975 NSCLC cells. CD8+ T cell-mediated NSCLC cell killing was employed to demonstrate the functional effects of PD-L1 siRNA knock-down. Fluorescent siRNAs were used to visualise siRNA uptake in cells as well as to enable biodistribution studies in BALB/c mice.

RESULTS

Our results showed that PEG12-KL4 was efficient in mediating siRNA knock-down of EGFR and PD-L1 in various NSCLC cells. Importantly, the PEG12-KL4 peptide enabled significantly better siRNA delivery than the commercial Lipofectamine 2000 reagent. We hypothesised that PEG12-KL4 peptide enabled siRNA to either escape from or bypass endosomal degradation as indicated by confocal fluorescence imaging. Notably, combined knock-down of EGFR and PD-L1 in NCI-H1975 cells resulted in better effector T cell-mediated cancer cell killing than knock-down of PD-L1 alone. Moreover, biodistribution of PEG12-KL4/siRNA complexes following intravenous administration revealed poor lung delivery with the fluorescent siRNA accumulating in the liver. In contrast, intratracheal delivery of PEG12-KL4/siRNA complexes resulted in the fluorescent siRNA to be detected in the lung with retarded renal excretion.

CONCLUSION

In conclusion, we demonstrated that the co-delivery of siRNAs targeting EGFR and PD-L1 using PEG12-KL4 is feasible and represents a promising future strategy to treat NSCLC, whereby pulmonary siRNA delivery is favourable to intravenous administration.

Durvalumab and taxane family combination therapy enhances the antitumoral effects for NSCLC: An in vitro study

Immunotherapy has lately become the most preferred cancer treatment method, and for non-small cell lung cancer (NSCLC) first-line treatment, there are many immunotherapy options. This study aimed to assess the effectiveness and toxicity of paclitaxel (PTX), docetaxel (DTX) chemotherapy, immune checkpoint inhibitor treatment (durvalumab; DVL), and their combination in NSCLC. A-549 cells were treated with DVL in combination with PTX and DTX (a quarter of the IC50 ) to investigate their anticancer effects on these cells. The MTT assay, wound healing tests, and double-staining with Annexin V/PI were used to assess the cell viability, apoptosis, and migration. The results showed that a combination of 0.35 mg/mL DVL with 6.5 μg/mL PTX and 1.75 μg/mL DTX produced a synergistic effect with CI values of 0.88, 0.37, and 0.81, respectively. Moreover, the PTX + DTX + DVL combination led to a significantly increased apoptotic rate up to 88.70 ± 3.39% in the A549 cell line compared to monotherapy (p < .001). In addition, we found that the combination therapy with these agents increased the expression level of Bax, Cas-3, p53, and Bax/Bcl-2 ratio in all experimental groups. In conclusion, the results suggest that combining anti-PD-L1 antibody therapy with chemotherapy may provide a promising approach to enhance treatment outcomes and be a potentially efficacious strategy for treating NSCLC patients. Further research and clinical investigations are needed to elucidate the underlying molecular mechanisms and validate the therapeutic potential of these compounds in vivo.

Clinical advances in EGFR-TKI combination therapy for EGFR-mutated NSCLC: a narrative review

Background and Objective

Mutations located in epidermal growth factor receptor (EGFR) tyrosine kinase domains have been described as the 'Achilles heel' of non-small cell lung cancer (NSCLC) and can be targeted by epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs). However, the clinical benefits of EGFR-TKIs are limited, and drug resistance inevitably occurs in NSCLC patients after long-term exposure to certain drugs. EGFR-TKI combination therapies, including combined targeted therapy, radiotherapy, chemotherapy, and immunotherapy, have shown promise in addressing this issue. This literature review analyzed the rationale and controversies of clinical research related to various EGFR-TKI combination therapies.

Methods

The PubMed database was searched to retrieve articles published from January 1, 2001 to April 15, 2023 using the following Medical Subject Headings (MeSH) terms: "EGFR-mutated non-small cell lung cancer" and "clinical trial". Google Scholar was also reviewed to retrieve additional articles. The search was limited to articles published in English.

Key Content and Findings

In this review, we summarized EGFR-TKI combination therapies, including combined targeted therapy, radiotherapy, chemotherapy, and immunotherapy, most of which have shown efficacy and safety in patients with EGFR-mutated NSCLC. A number of clinical studies with large sample sizes have analyzed the activity and toxicity of combined therapies and explored potential and well-tolerated treatment options.

Conclusions

EGFR mutations have been detected in many NSCLC patients and can be targeted by EGFR-TKIs. However, drug resistance after long-term exposure remains a significant challenge for this type of treatment. Most clinical trials have shown that the combination of EGFR-TKIs and targeted therapy, chemotherapy, radiotherapy or immunotherapy is efficacious and safe in the treatment of EGFR-mutated NSCLC. It should be noted that in some instances, serious adverse events have led to the termination of trials. However, EGFR-TKI combination therapy is indeed an effective approach for the treatment of patients with EGFR-mutated NSCLC and deserves further development.

Mutant PIK3CA as a negative predictive biomarker for treatment with a highly selective PIM1 inhibitor in human colon cancer

Significant improvement in targeted therapy for colorectal cancer (CRC) has occurred over the past few decades since the approval of the EGFR inhibitor cetuximab. However, cetuximab is used only for patients possessing the wild-type oncogene KRAS, NRAS, and BRAF, and even most of these eventually acquire therapeutic resistance, via activation of parallel oncogenic pathways such as RAS-MAPK or PI3K/Akt/mTOR. The two aforementioned pathways also contribute to the development of therapeutic resistance in CRC patients, due to compensatory and feedback mechanisms. Therefore, combination drug therapies (versus monotherapy) targeting these multiple pathways may be necessary for further efficacy against CRC. In this study, we identified PIK3CA mutant (PIK3CA MT) as a determinant of resistance to SMI-4a, a highly selective PIM1 kinase inhibitor, in CRC cell lines. In CRC cell lines, SMI-4a showed its effect only in PIK3CA wild type (PIK3CA WT) cell lines, while PIK3CA MT cells did not respond to SMI-4a in cell death assays. In vivo xenograft and PDX experiments confirmed that PIK3CA MT is responsible for the resistance to SMI-4a. Inhibition of PIK3CA MT by PI3K inhibitors restored SMI-4a sensitivity in PIK3CA MT CRC cell lines. Taken together, these results demonstrate that sensitivity to SMI-4a is determined by the PIK3CA genotype and that co-targeting of PI3K and PIM1 in PIK3CA MT CRC patients could be a promising and novel therapeutic approach for refractory CRC patients.

Canine oral melanoma with suspected pulmonary metastasis: Combination of immunotherapy and tyrosine kinase inhibitor treatment

This case report follows a 10-year-old castrated male Miniature Schnauzer dog presented with a history of incomplete surgical resection of an oral malignant melanoma (amelanotic type) on the right mandible. Melanoma vaccine therapy was administered due to incomplete surgical resection, however, new masses were detected on the contralateral mandible and suspected pulmonary metastasis occurred at 2 weeks and 7 months, respectively, following the first melanoma vaccination. At the time of detecting the pulmonary metastasis, targeted chemotherapy was initiated with the owner's consent using imatinib (10 mg/kg/day, p.o.), a tyrosine kinase inhibitor (TKI). The patient did not show any significant adverse events related to both anticancer treatments. Three months following the first dose of imatinib, the absence of the suspected pulmonary metastatic nodules on radiography indicated complete remission. In conclusion, this report describes the achievement of clinical remission of suspected pulmonary metastatic oral malignant melanoma and an extension of survival time in a dog given a combination treatment of immunotherapy and tyrosine kinase inhibitor.

Efficacy of epidermal growth factor receptor tyrosine kinase inhibitor in the treatment of patients with nonsmall cell lung cancer

This study aimed to examine the effectiveness of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) in treating patients with nonsmall cell lung cancer (NSCLC), and the association between clinical characteristics and effectiveness. This retrospective study included 140 patients with NSCLC admitted to our hospital between July 2020 and July 2022. The patients were categorized into 2 groups according to the treatment that they received: a comparison group (67 patients) and a research group (73 patients). The comparison group received conventional chemotherapy, and the research group received conventional chemotherapy and EGFR-TKI-targeted therapy. The immune and tumor marker levels, clinical response, and relationship between clinical characteristics and response to therapy were compared between the 2 groups before and after treatment. After treatment, the levels of neuron-specific enolase and carcinoembryonic antigen (CEA) and CD8+ count were significantly lower, and forced vital capacity, forced expiratory volume in 1 second, and CD4+ count were significantly higher in the research group than in the comparison group. After treatment, the clinical effectiveness in the 2 groups significantly improved, and the disease control rate in the research group was significantly higher than that in the comparison group (89% vs 69%, P = .014). The bivariate analysis revealed that smoking history, ECOG Performance Status score, and CEA level were significantly associated with clinical effectiveness. Conventional chemotherapy combined with EGFR-TKI-targeted therapy is effective in patients with NSCLC and has a clinically significant effect on improving patients' immune function and lung function.

Role of pelitinib in the regulation of migration and invasion of hepatocellular carcinoma cells via inhibition of Twist1

BACKGROUND

Overexpression of Twist1, one of the epithelial-mesenchymal transition-transcription factors (EMT-TFs), is associated with hepatocellular carcinoma (HCC) metastasis. Pelitinib is known to be an irreversible epidermal growth factor receptor tyrosine kinase inhibitor that is used in clinical trials for colorectal and lung cancers, but the role of pelitinib in cancer metastasis has not been studied. This study aimed to investigate the anti-migration and anti-invasion activities of pelitinib in HCC cell lines.

METHODS

Using three HCC cell lines (Huh7, Hep3B, and SNU449 cells), the effects of pelitinib on cell cytotoxicity, invasion, and migration were determined by cell viability, wound healing, transwell invasion, and spheroid invasion assays. The activities of MMP-2 and -9 were examined through gelatin zymography. Through immunoblotting analyses, the expression levels of EMT-TFs (Snail1, Twist1, and ZEB1) and EMT-related signaling pathways such as mitogen-activated protein kinases (MAPKs) and Akt signaling pathways were measured. The activity and expression levels of target genes were analyzed by reporter assay, RT-PCR, quantitative RT-PCR, and immunoblotting analysis. Statistical analysis was performed using one-way ANOVA with Dunnett's Multiple comparison tests in Prism 3.0 to assess differences between experimental conditions.

RESULTS

In this study, pelitinib treatment significantly inhibited wound closure in various HCC cell lines, including Huh7, Hep3B, and SNU449. Additionally, pelitinib was found to inhibit multicellular cancer spheroid invasion and metalloprotease activities in Huh7 cells. Further investigation revealed that pelitinib treatment inhibited the migration and invasion of Huh7 cells by inducing Twist1 degradation through the inhibition of MAPK and Akt signaling pathways. We also confirmed that the inhibition of cell motility by Twist1 siRNA was similar to that observed in pelitinib-treated group. Furthermore, pelitinib treatment regulated the expression of target genes associated with EMT, as demonstrated by the upregulation of E-cadherin and downregulation of N-cadherin.

CONCLUSION

Based on our novel finding of pelitinib from the perspective of EMT, pelitinib has the ability to inhibit EMT activity of HCC cells via inhibition of Twist1, and this may be the potential mechanism of pelitinib on the suppression of migration and invasion of HCC cells. Therefore, pelitinib could be developed as a potential anti-cancer drug for HCC.

The next generation of EGFR inhibitors: a patenting perspective of PROTACs based EGFR degraders

INTRODUCTION

Abnormal expression of epidermal growth factor receptor (EGFR) contributes to tumor development, especially in non-small cell lung cancer (NSCLC). Although multiple inhibitors have been developed to target diverse EGFR mutations and several have been approved, the inevitable drug resistance and side effect remain a challenge, which motivates novel strategies. Proteolysis-targeting chimeras (PROTACs) have been gaining momentum for their potential as novel therapeutics for human diseases by triggering protein degradation. To date, various potent and specific EGFR PROTACs have been discovered and some of them have entered clinical trials.

AREAS COVERED

This review provides an overview of EGFR degraders in patents from 2016 to 2022. It provides an update of the discovery strategies, chemical structures, and molecular profiling of all available EGFR PROTACs. SciFinder, PubMed, Web of Science, EPO, and CNIPA databases were used for searching the literature and patents for EGFR PROTACs.

EXPERT OPINION

By employing the PROTAC technology, highly potent and selective EGFR degraders based on four generation EGFR inhibitors have been developed, which offer a new strategy to target EGFR mutations and overcome the drug resistance. Despite the satisfactory result in vitro and in vivo studies, their therapeutic value awaits more rigorous preclinical testing and clinical investigation.

Role and mechanistic actions of protein kinase inhibitors as an effective drug target for cancer and COVID

Kinases can be grouped into 20 families which play a vital role as a regulator of neoplasia, metastasis, and cytokine suppression. Human genome sequencing has discovered more than 500 kinases. Mutations of the kinase itself or the pathway regulated by kinases leads to the progression of diseases such as Alzheimer's, viral infections, and cancers. Cancer chemotherapy has made significant leaps in recent years. The utilization of chemotherapeutic agents for treating cancers has become difficult due to their unpredictable nature and their toxicity toward the host cells. Therefore, targeted therapy as a therapeutic option against cancer-specific cells and toward the signaling pathways is a valuable avenue of research. SARS-CoV-2 is a member of the Betacoronavirus genus that is responsible for causing the COVID pandemic. Kinase family provides a valuable source of biological targets against cancers and for recent COVID infections. Kinases such as tyrosine kinases, Rho kinase, Bruton tyrosine kinase, ABL kinases, and NAK kinases play an important role in the modulation of signaling pathways involved in both cancers and viral infections such as COVID. These kinase inhibitors consist of multiple protein targets such as the viral replication machinery and specific molecules targeting signaling pathways for cancer. Thus, kinase inhibitors can be used for their anti-inflammatory, anti-fibrotic activity along with cytokine suppression in cases of COVID. The main goal of this review is to focus on the pharmacology of kinase inhibitors for cancer and COVID, as well as ideas for future development.

Real-world clinical practice and outcomes in treating stage III non-small cell lung cancer: KINDLE-Asia subset

Introduction

Stage III non-small cell lung cancer (NSCLC) is a heterogeneous disease requiring multimodal treatment approaches. KINDLE-Asia, as part of a real world global study, evaluated treatment patterns and associated survival outcomes in stage III NSCLC in Asia.

Methods

Retrospective data from 57 centers in patients with stage III NSCLC diagnosed between January 2013 and December 2017 were analyzed. Median progression free survival (mPFS) and median overall survival (mOS) estimates with two sided 95% confidence interval (CI) were determined by applying the Kaplan-Meier survival analysis.

Results

Of the total 1874 patients (median age: 63.0 years [24 to 92]) enrolled in the Asia subset, 74.8% were men, 54.7% had stage IIIA disease, 55.7% had adenocarcinoma, 34.3% had epidermal growth factor receptor mutations (EGFRm) and 50.3% had programmed death-ligand 1 (PD-L1) expression (i.e. PD-L1 ≥1%). Of the 31 treatment approaches as initial therapy, concurrent chemoradiotherapy (CRT) was the most frequent (29.3%), followed by chemotherapy (14.8%), sequential CRT (9.5%), and radiotherapy (8.5%). Targeted therapy alone was used in 81 patients of the overall population. For the Asia cohort, the mPFS and mOS were 12.8 months (95% CI, 12.2–13.7) and 42.3 months (95% CI, 38.1–46.8), respectively. Stage IIIA disease, Eastern Cooperative Oncology Group ≤1, age ≤65 years, adenocarcinoma histology and surgery/concurrent CRT as initial therapy correlated with better mOS (p &lt; 0.05).

Conclusions

The results demonstrate diverse treatment patterns and survival outcomes in the Asian region. The high prevalence of EGFRm and PD-L1 expression in stage III NSCLC in Asia suggests the need for expanding access to molecular testing for guiding treatment strategies with tyrosine kinase inhibitors and immunotherapies in this region.

Edible and cation-free kiwi fruit derived vesicles mediated EGFR-targeted siRNA delivery to inhibit multidrug resistant lung cancer

Clinically, activated EGFR mutation associated chemo-drugs resistance has severely threaten NSCLC patients. Nanoparticle based small interfering RNA (siRNA) therapy representing another promising alternative by silencing specific gene while still suffered from charge associated toxicity, strong immunogenicity and poor targetability. Herein, we reported a novel EGFR-mutant NSCLC therapy relying on edible and cation-free kiwi-derived extracellular vesicles (KEVs), which showed sevenfold enhancement of safe dosage compared with widely used cationic liposomes and could be further loaded with Signal Transducer and Activator of Transcription 3 interfering RNA (siSTAT3). siSTAT3 loaded KEVs (STAT3/KEVs) could be easily endowed with EGFR targeting ability (STAT3/EKEVs) and fluorescence by surface modification with tailor-making aptamer through hydrophobic interaction. STAT3/EKEVs with a controlled size of 186 nm displayed excellent stability, high specificity and good cytotoxicity towards EGFR over-expressing and mutant PC9-GR4-AZD1 cells. Intriguingly, the systemic administration of STAT3/EKEVs significantly suppressed subcutaneous PC9-GR4-AZD1 tumor xenografts in nude mice by STAT3 mediated apoptosis. This safe and robust KEVs has emerged as the next generation of gene delivery platform for NSCLC therapy after multiple drug-resistance.

Nanotechnology-based approaches overcome lung cancer drug resistance through diagnosis and treatment

Lung cancer continues to be a malignant tumor with high mortality. Two obstacles interfere with curative therapy of lung cancer: (i) poor diagnosis at the early stages, as symptoms are not specific or asymptomatic; and (ii) invariably emerging drug resistance after treatment. Some factors contributing to drug resistance include preexisting genetic/genomic drug-resistant alteration(s); activation of adaptive drug resistance pathways; remodeling of the tumor microenvironment; and pharmacological mechanisms or activation of drug efflux pumps. Despite the mechanisms explored to better understand drug resistance, a gap remains between molecular understanding and clinical application. Therefore, facilitating the translation of basic science into the clinical setting is a great challenge. Nanomedicine has emerged as a promising tool for cancer treatment. Because of their excellent physicochemical properties and enhanced permeability and retention effects, nanoparticles have great potential to revolutionize conventional lung cancer diagnosis and combat drug resistance. Nanoplatforms can be designed as carriers to improve treatment efficacy and deliver multiple drugs in one system, facilitating combination treatment to overcome drug resistance. In this review, we describe the difficulties in lung cancer treatment and review recent research progress on nanoplatforms aimed at early diagnosis and lung cancer treatment. Finally, future perspectives and challenges of nanomedicine are also discussed.

Impact of TP53 Mutations on EGFR-Tyrosine Kinase Inhibitor Efficacy and Potential Treatment Strategy

BACKGROUND

We investigated the impact of factors that influence TP53 mutations on the efficacy of EGFR-tyrosine kinase inhibitors and potential treatment strategies.

MATERIALS AND METHODS

Tumor samples were collected to screen gene mutations by next-generation sequencing, as well as the patients' baseline characteristics. The overall response to treatment with TKIs was evaluated based on interval computed tomography scans at each follow-up time point. A Fisher's exact test and log-rank test were used to determine the statistical differences in this study.

RESULTS

A total of 1134 clinical samples were collected from NSCLC patients, and TP53^mut was identified in 644 cases and EGFR^mut in 622 cases. A low frequency of TP53^mut or more than 50% EGFR co-mutation rate were related to the prognosis of TKI-treated patients. In addition, TP53^mut in the region outside of the DB domain had the strongest correlation with TKI resistance, whereas various types of mutations in the DB domain only had an impact on PFS. A grouping study of EGFR-TKI-based treatment revealed that EGFR-TKIs with chemotherapy were associated with more significant survival benefits for patients with prognostic TP53^mut, whereas EGFR-TKI therapy was favorable for TP53^wt patients. Furthermore, TP53^mut could shorten the time to the relapse of postoperative patients, who will also likely respond well to EGFR-TKIs with chemotherapy.

CONCLUSION

Various characteristics of TP53^mut affect the prognosis of TKI-treated patients to varying degrees. EGFR-TKIs with chemotherapy were benefit for patients' survival with prognostic TP53^mut, which provides an important reference for treatment management of EGFR^mut patients.

A novel combination treatment of antiADAM17 antibody and erlotinib to overcome acquired drug resistance in non-small cell lung cancer through the FOXO3a/FOXM1 axis

After the identification of specific epidermal growth factor receptor (EGFR)-activating mutations as one of the most common oncogenic driver mutations in non-small cell lung cancer (NSCLC), several EGFR-tyrosine kinase inhibitors (EGFR-TKIs) with different clinical efficacies have been approved by various health authorities in the last two decades in targeting NSCLC harboring specific EGFR-activating mutations. However, most patients whose tumor initially responded to the first-generation EGFR-TKI developed acquired resistance. In this study, we developed a novel combination strategy, "antiADAM17 antibody A9(B8) + EGFR-TKIs", to enhance the efficacy of EGFR-TKIs. The addition of A9(B8) was shown to restore the effectiveness of erlotinib and overcome acquired resistance. We found that when A9(B8) antibody was treated with erlotinib or gefitinib, the combination treatment synergistically increased apoptosis in an NSCLC cell line and inhibited tumor growth in vivo. Interestingly, the addition of A9(B8) could only reduce the survival of the erlotinib-resistant NSCLC cell line and inhibit the growth of erlotinib-resistant tumors in vivo but not gefitinib-resistant cells. Furthermore, we revealed that A9(B8) overcame erlotinib resistance through the FOXO3a/FOXM1 axis and arrested the cell cycle at the G₁/S phase, resulting in the apoptosis of cancer cells. Hence, this study establishes a novel, promising strategy for overcoming acquired resistance to erlotinib through the FOXO3a/FOXM1 axis by arresting the cell cycle at the G₁/S phase.

PI3Kβ inhibition enhances ALK-inhibitor sensitivity in ALK-rearranged lung cancer

Treatment with anaplastic lymphoma kinase (ALK) inhibitors significantly improves outcome for non-small-cell lung cancer (NSCLC) patients with ALK-rearranged tumors. However, clinical resistance typically develops over time and, in the majority of cases, resistance mechanisms are ALK-independent. We generated tumor cell cultures from multiple regions of an ALK-rearranged clinical tumor specimen and deployed functional drug screens to identify modulators of ALK-inhibitor response. This identified a role for PI3Kβ and EGFR inhibition in sensitizing the response regulating resistance to ALK inhibition. Inhibition of ALK elicited activation of EGFR, and subsequent MAPK and PI3K-AKT pathway reactivation. Sensitivity to ALK targeting was enhanced by inhibition or knockdown of PI3Kβ. In ALK-rearranged primary cultures, the combined inhibition of ALK and PI3Kβ prevented the EGFR-mediated ALK-inhibitor resistance, and selectively targeted the cancer cells. The combinatorial effect was seen also in the background of TP53 mutations and in epithelial-to-mesenchymal transformed cells. In conclusion, combinatorial ALK- and PI3Kβ-inhibitor treatment carries promise as a treatment for ALK-rearranged NSCLC.

Design, synthesis and biological evaluation of novel macrocyclic derivatives bearing aniline pyrimidine scaffolds as EGFR-TKIs

Based on EGFR-TKI Osimertinib as lead compound, a series of novel macrocyclic derivatives bearing aniline pyrimidine scaffolds were designed and synthesized by macrocyclization. Their structures were identified by ¹H NMR, ¹³C NMR, ¹⁹F NMR and HRMS. The pharmacological activities of the target compounds were tested and the preliminary structure-activity relationship was discussed. Among them, 17-membered ring compound H1 displayed the best inhibitory activities against EGFR^L858R/T790M and EGFR^{d746-750/T790M} with IC₅₀ value of 2.92 nM and 0.34 nM, respectively. Exhilaratingly, 17-membered ring compound H7 possessed the most potent antiproliferative activity against BaF3-EGFR^del19/T790M cell lines (IC₅₀ = 0.035 µm), which rivaled that of Osimertinib (IC₅₀ = 0.033 µm).

Efficacy of epidermal growth factor receptor tyrosine kinase inhibitors in patients with recurrent non-small cell lung cancer after definitive concurrent chemoradiation or radiotherapy

PURPOSE

Whether prior radiotherapy (RT) affects the response of EGFR-mutated non-small cell lung cancer (NSCLC) to EGFR tyrosine kinase inhibitor (TKI) remains elusive.

METHODS

Patients with EGFR-mutated NSCLC treated with EGFR TKIs who recurred after curative treatment at Asan Medical Center, Seoul, Korea were included. The progression-free survival (PFS) and overall survival (OS) from the initiation of EGFR TKI in patients who recurred after definitive RT were analyzed and compared to the outcomes of RT-naïve patients with advanced NSCLC treated with EGFR TKIs from previously reported prospective clinical trial results.

RESULTS

A total of 60 patients who recurred after definitive RT were included. The median age was 70 years (range, 38-88), with 24 patients (40.0%) being males. Among the 60 patients, 52 patients (86.7%) had exon 19 deletion or L858R mutation, with 49 patients (81.7%) receiving gefitinib as the first-line EGFR TKI. The median PFS and OS from the initiation of EGFR TKI were 10.4 months (95% confidence interval [CI], 7.4-13.2) and 21.3 months (95% CI, 13.4-28.8), respectively.

CONCLUSION

The EGFR TKI efficacy in EGFR-mutated patients with NSCLC who recurred after RT was comparable with that in historic controls of RT-naïve patients with advanced NSCLC treated with EGFR TKIs, indicating that RT may not affect EGFR TKI efficacy.

Design, synthesis and evaluation of the Brigatinib analogues as potent inhibitors against tertiary EGFR mutants (EGFRdel19/T790M/C797S and EGFRL858R/T790M/C797S)

Although epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have demonstrated encouraging clinical outcomes for patients with EGFR-mutated non-small cell lung cancer, a considerable number of patients will develop drug resistance and eventually undergo disease progression after taking EGFR-TKIs for a period of time. EGFR^{del19/T790M/C797S} and EGFR^{L858R/T790M/C797S} are two most prevalent tertiary EGFR mutants identified in Osimertinib-resistant tumors and currently there is no therapy approved clinically targeting these mutants. In this study, we designed and synthesized a series of novel 4th generation EGFR inhibitors based on scaffold of Brigatinib. After extensive SAR studies, compound 23, the most promising candidate, exhibited strong biochemical potencies against EGFR^{del19/T790M/C797S}, EGFR^{L858R/T790M/C797S} and other clinically relevant EGFR mutants while sparing wild type EGFR. In cellular assays, compound 23 potently inhibited proliferation of BaF3^{EGFR del19/T790M/C797S} and PC-9^{EGFR del19/T790M/C797S}. Moreover, compound 23 demonstrated good DMPK profile in mouse PK study.

Combination Effect of Cilengitide with Erlotinib on TGF-β1-Induced Epithelial-to-Mesenchymal Transition in Human Non-Small Cell Lung Cancer Cells

The epithelial-to-mesenchymal transition (EMT) is important for morphogenesis during development and is mainly induced by transforming growth factor (TGF)-β. In lung cancer, EMT is characterized by the transformation of cancer cells into a mobile, invasive form that can transit to other organs. Here, using a non–small cell lung cancer (NSCLC) cell line, we evaluated the EMT-related effects of the epidermal growth factor receptor inhibitor erlotinib alone and in combination with cilengitide, a cyclic RGD-based integrin antagonist. Erlotinib showed anti-proliferative and inhibitory effects against the TGF-β1–induced EMT phenotype in NSCLC cells. Compared with erlotinib alone, combination treatment with cilengitide led to an enhanced inhibitory effect on TGF-β1–induced expression of mesenchymal markers and invasion in non–small cell lung cancer A549 cells. These results suggest that cilengitide could improve anticancer drug efficacy and contribute to improved treatment strategies to inhibit and prevent EMT-based cancer progression.

The different overall survival between single-agent EGFR-TKI treatment and with bevacizumab in non-small cell lung cancer patients with brain metastasis

Comparison of epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) monotherapy or with bevacizumab in real-world non-small cell lung cancer (NSCLC) patients was lacking. 310 patients of advanced NSCLC with common EGFR mutation receiving first-generation EGFR-TKI monotherapy or with bevacizumab were included and propensity-score matched. Progression-free survival (PFS), overall survival (OS) and secondary T790M mutation were analysed. Patients receiving EGFR-TKI and bevacizumab were significantly younger, had better performance status and with high incidence of brain metastasis (55.8%). In the propensity-score matched cohort, PFS (13.5 vs. 13.7 months; log-rank p = 0.700) was similar between the two groups. The OS (61.3 vs. 34.2 months; log-rank p = 0.010) and risk reduction of death (HR 0.42 [95% CI 0.20–0.85]; p = 0.017) were significantly improved in EGFR-TKI plus bevacizumab group. Analysis of treatment by brain metastasis status demonstrated EGFR-TKI plus bevacizumab in patients with brain metastasis was associated with significant OS benefit compared to other groups (log-rank p = 0.030) and these patients had lower early-CNS and early-systemic progressions. The secondary T790M did not significantly differ between EGFR-TKI plus bevacizumab and EGFR-TKI monotherapy groups (66.7% vs. 75.0%, p = 0.460). Forty-one (31.1%) and 31 (23.5%) patients received subsequent osimertinib and chemotherapy, respectively. The post-progression OS of osimertinib and chemotherapy were 22.1 and 44.9 months in EGFR-TKI plus bevacizumab group and were 10.0 and 14.1 months in EGFR-TKI monotherpay group, respectively. First-generation EGFR-TKI with bevacizumab improved treatment efficacy in real-world patients of NSCLC with EGFR mutation. Patients with brain metastasis received additional OS benefit from this treatment.

PTP-PEST Regulated Membranous/Cytoplasmic Translocation of p120ctn in the Lung Cancer Resistance to Tyrosine Kinase Inhibitor

Our previous studies indicate that resistance induction using first-generation tyrosine kinase inhibitors (TKIs) in lung cancer is accompanied with p120-catenin (p120ctn) cytoplasmic translocation from the membrane. However, the molecular mechanism underlying p120ctn intracytoplasmic translocation has not yet been reported. We performed immunohistochemistry to detect the correlation of p120ctn distribution with protein tyrosine phosphatase non-receptor type 12 (PTP-PEST) and p120ctn Y335 phosphorylation levels in non-small cell lung cancer (NSCLC) patients. After resistance induction using first-generation TKIs in lung cancer cells, Western blotting and substrate trapping were used to assess PTP-PEST expression and its influence on p120ctn Y335 phosphorylation, as well as the role of p120ctn Y335 phosphorylation on the association of p120ctn with E-cadherin and p120ctn membrane/cytoplasm translocation. In 197 samples collected from NSCLC patients, cytoplasmic p120ctn and enhanced p120ctn Y335 phosphorylation were associated with decreased PTP-PEST. After resistance induction using gefitinib, decreased PTP-PEST expression was accompanied by enhanced phosphorylation of p120ctn Y335 and p120ctn translocated to the cytoplasm. In gefitinib-resistant cells, PTP-PEST overexpression restrained p120ctn Y335 phosphorylation and restored membrane p120ctn expression. PTP-PEST enhanced the interaction of p120ctn with E-cadherin and elevated p120ctn membrane expression. However, increased p120ctn-Y335F mutant had no effect on p120ctn interaction with E-cadherin and membrane/cytoplasm translocation compared with the control group. In conclusion, resistance to first-generation TKIs inhibited PTP-PEST expression, which promoted p120ctn-Y335 phosphorylation and reduced the interaction of p120ctn with E-cadherin, resulting in p120ctn cytoplasmic translocation.

FGFC1 Selectively Inhibits Erlotinib-Resistant Non-Small Cell Lung Cancer via Elevation of ROS Mediated by the EGFR/PI3K/Akt/mTOR Pathway

Non-small cell lung cancer (NSCLC) is one of the most common malignancies in the world. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have been used as a first-line treatment for patients harboring with EGFR mutations in advanced NSCLC. Nevertheless, the drug resistance after continuous and long-term chemotherapies considerably limits its clinical efficacy. Therefore, it is of great importance to develop new chemotherapeutic agents and treatment strategies to conquer the drug resistance. FGFC1 (Fungi fibrinolytic compound 1), a type of bisindole alkaloid from a metabolite of the rare marine fungi Starchbotrys longispora. FG216, has exhibited excellent fibrinolytic and anti-inflammatory activity. However, the potent efficacy of FGFC1 in human cancer therapy requires further study. Herein, we demonstrated that FGFC1 selectively suppressed the growth of NSCLC cells with EGFR mutation. Mechanistically, FGFC1 treatment significantly induced the apoptosis of erlotinib-resistant NSCLC cells H1975 in a dose-dependent manner, which was proved to be mediated by mitochondrial dysfunction and elevated accumulation of intracellular reactive oxygen species (ROS). Scavenging ROS not only alleviated FGFC1-induced apoptosis but also relieved the decrease of phospho-Akt. We further confirmed that FGFC1 significantly decreased the phosphorylation of protein EGFR, phosphatidylinositol 3-kinase (PI3K), protein kinase B (Akt), and mammalian target of rapamycin (mTOR) in H1975 cells. Notably, PI3K inhibitor (LY294002) could promote the accumulation of ROS and the expression levels of apoptosis-related proteins induced by FGFC1. Molecular dynamics simulations indicated that FGFC1 can inhibit EGFR and its downstream PI3K/Akt/mTOR pathway through directly binding to EGFR, which displayed a much higher binding affinity to EGFRT790M/L858R than EGFRWT. Additionally, FGFC1 treatment also inhibited the migration and invasion of H1975 cells. Finally, FGFC1 effectively inhibited tumor growth in the nude mice xenograft model of NSCLC. Taken together, our results indicate that FGFC1 may be a potential candidate for erlotinib-resistant NSCLC therapy.

FGFC1 Exhibits Anti-Cancer Activity via Inhibiting NF-κB Signaling Pathway in EGFR-Mutant NSCLC Cells

FGFC1, an active compound isolated from the culture of marine fungi Stachybotrys longispora FG216, elicits fibrinolytic, anti-oxidative, and anti-inflammatory activity. We have previously reported that FGFC1 inhibited the proliferation, migration, and invasion of the non-small cell lung cancer (NSCLC) cells in vitro. However, the precise mechanisms of FGFC1 on NSCLC and its anti-cancer activity in vivo remains unclear. Hence, this study was focused to investigate the effects and regulatory mechanisms of FGFC1 on two NSCLC cell lines, EGFR-mutant PC9 (ex19del) and EGFR wild-type H1299. Results suggested that FGFC1 significantly inhibited proliferation, colony formation, as well as triggered G0/G1 arrest and apoptosis of PC9 cells in a dose- and time-dependent manner, but no obvious inhibitory effects were observed in H1299 cells. Subsequently, transcriptome analysis revealed that FGFC1 significantly down-regulated 28 genes related to the NF-κB pathway, including IL-6, TNF-α, and ICAM-1 in the PC9 cells. We further confirmed that FGFC1 decreased the expression of protein p-IKKα/β, p-p65, p-IκB, IL-6, and TNF-α. Moreover, NF-κB inhibitor PDTC could strengthen the effects of FGFC1 on the expression of CDK4, Cyclin D1, cleaved-PARP-1, and cleaved-caspase-3 proteins, suggesting that the NF-κB pathway plays a major role in FGFC1-induced cell cycle arrest and apoptosis. Correspondingly, the nuclear translocation of p-p65 was also suppressed by FGFC1 in PC9 cells. Finally, the intraperitoneal injection of FGFC1 remarkably inhibited PC9 xenograft growth and decreased the expression of Ki-67, p-p65, IL-6, and TNF-α in tumors. Our results indicated that FGFC1 exerted anti-cancer activity in PC9 cells via inhibiting the NF-κB signaling pathway, providing a possibility for FGFC1 to be used as a lead compound for the treatment of NSCLC in the future.

Afatinib Treatment Alone or with Bevacizumab in a Real-World Cohort of Non-Small Cell Lung Cancer Patients with Epidermal Growth Factor Receptor Mutation

BACKGROUND

Treatment outcome between afatinib alone or with bevacizumab in non-small cell lung cancer (NSCLC) patient with epidermal growth factor receptor (EGFR) mutation remains insufficiently reported.

METHODS

A total of 405 advanced NSCLC patients with sensitizing-EGFR mutation receiving first-line single-agent afatinib or with bevacizumab were grouped and propensity score-matched. Progression-free survival (PFS), overall survival (OS) and secondary T790M mutation were analyzed.

RESULTS

In the original cohort, 367 (90.6%) patients received afatinib treatment alone and 38 (9.4%) patients received afatinib plus bevacizumab. Patients who received bevacizumab combination were significantly younger (54.6 ± 10.9 vs. 63.9 ± 11.5; p < 0.001) compared to the afatinib alone group. After propensity score matching, the afatinib alone and afatinib plus bevacizumab groups contained 118 and 34 patients, respectively. A non-significantly higher objective response was noted in the afatinib plus bevacizumab group (82.4% vs. 67.8%; p = 0.133). In the propensity score-matched cohort, a bevacizumab add-on offered no increased PFS (16.1 vs. 15.0 months; p = 0.500), risk reduction of progression (HR 0.85 [95% CI, 0.52-1.40]; p = 0.528), OS benefit (32.1 vs. 42.0 months; p = 0.700), nor risk reduction of death (HR 0.85 [95% CI, 0.42-1.74] p = 0.660) compared to the single-agent afatinib. The secondary T790M rate in afatinib plus bevacizumab and afatinib alone groups was similar (56.3% vs. 49.4%, p = 0.794). Multivariate analysis demonstrated that EGFR L858R (OR 0.51 [95% CI, 0.26-0.97]; p = 0.044), EGFR uncommon mutation (OR 0.14 [95% CI, 0.02-0.64]; p = 0.021), and PFS longer than 12 months (OR 2.71 [95% CI, 1.39-5.41]; p = 0.004) were independent predictors of secondary T790M positivity.

CONCLUSION

Bevacizumab treatment showed moderate efficacy in real-world, afatinib-treated NSCLC patients with EGFR-sensitizing mutation.

Cell Behavior of Non-Small Cell Lung Cancer Is at EGFR and MicroRNAs Hands

Lung cancer is a complex disease associated with gene mutations, particularly mutations of Kirsten Rat Sarcoma Viral Oncogene Homolog (KRAS) and epidermal growth factor receptor (EGFR). Non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) are the two major types of lung cancer. The former includes most lung cancers (85%) and are commonly associated with EGFR mutations. Several EGFR-tyrosine kinase inhibitors (EGFR-TKIs), including erlotinib, gefitinib, and osimertinib, are effective therapeutic agents in EGFR-mutated NSCLC. However, their effectiveness is limited by the development (acquired) or presence of intrinsic drug resistance. MicroRNAs (miRNAs) are key gene regulators that play a profound role in the development and outcomes for NSCLC via their role as oncogenes or oncosuppressors. The regulatory role of miRNA-dependent EGFR crosstalk depends on EGFR signaling pathway, including Rat Sarcoma/Rapidly Accelerated Fibrosarcoma/Mitogen-Activated Protein Kinase/Extracellular Signal-Regulated Kinase 1/2 (Ras/Raf/MEK/ERK1/2), Signal Transducer and Activator of Transcription (STAT), Nuclear Factor Kappa-Light-Chain-Enhancer of Activated B Cells (NF-kB), phosphoinositide 3-kinase/protein kinase B (PI3K/AKT), Janus kinase 1 (JAK1), and growth factor receptor-bound protein 2 (GRB2). Dysregulated expression of miRNAs affects sensitivity to treatment with EGFR-TKIs. Thus, abnormalities in miRNA-dependent EGFR crosstalk can be used as diagnostic and prognostic markers, as well as therapeutic targets in NSCLC. In this review, we present an overview of miRNA-dependent EGFR expression regulation, which modulates the behavior and progression of NSCLC.

A review on epidermal growth factor receptor's role in breast and non-small cell lung cancer

Epithelial growth factor receptor (EGFR) is a cell surface transmembrane receptor that mediates the tyrosine signaling pathway to carry the extracellular messages inside the cell and thereby alter the function of nucleus. This leads to the generation of various protein products to up or downregulate the cellular function. It is encoded by cell erythroblastosis virus oncogene B1, so called C-erb B1/ERBB2/HER-2 gene that acts as a proto-oncogene. It belongs to the HER-2 receptor-family in breast cancer and responds best with anti-Herceptin therapy (anti-tyrosine kinase monoclonal antibody). HER-2 positive breast cancer patient exhibits worse prognosis without Herceptin therapy. Similar incidence and prognosis are reported in other epithelial neoplasms like EGFR + lung non-small cell carcinoma and glioblastoma (grade IV brain glial tumor). Present study highlights the role and connectivity of EGF with various cancers via signaling pathways, cell surface receptors mechanism, macromolecules, mitochondrial genes and neoplasm. Present study describes the EGFR associated gene expression profiling (in breast cancer and NSCLC), relation between mitrochondrial genes and carcinoma, and several in vitro and in vivo models to screen the synergistic effect of various combination treatments. According to this study, although clinical studies including targeted treatments, immunotherapies, radiotherapy, TKi-EGFR combined targeted therapy have been carried out to investigate the synergism of combination therapy; however still there is a gap to apply the scenarios of experimental and clinical studies for further developments. This review will give an idea about the transition from experimental to most advanced clinical studies with different combination drug strategies to treat cancer.

EGFR Inhibitors Plus Bevacizumab are Superior Than EGFR Inhibitors Alone as First-Line Setting in Advanced NSCLC With EGFR Mutations and BIM Deletion Polymorphisms (BIM-CLICaP)

PURPOSE

BIM activation is essential for epidermal growth factor receptor ( EGFR)-tyrosine kinase inhibitor (TKI)–triggered apoptosis in EGFR-mutant non–small-cell lung cancer (NSCLC). A deletion in the intron two of the BIM gene results in generation of alternatively spliced isoforms that impairs their apoptotic response to TKIs, conferring the NSCLC cells intrinsic resistance to these medications. Patients with both alterations have poor clinical evolution. The current study aimed to investigate the clinical efficacy and tolerability of EGFR-TKIs plus bevacizumab (Bev) versus EGFR-TKIs alone as first-line treatment in advanced NSCLC patients with EGFR mutations and BIM deletions ( BIMdel).

MATERIALS AND METHODS

A retrospective analysis was conducted. BIMdel was detected using polymerase chain reaction analysis and direct sequencing of DNA. BIM protein expression was investigated by immunohistochemistry, and BIM mRNA levels by reverse transcriptase-polymerase chain reaction. Clinical characteristics, overall survival, progression-free survival (PFS), overall response rate (ORR), and treatment-related adverse events were compared between both groups.

RESULTS

Thirty-three patients were included; 15 received EGFR-TKIs, and 18 received EGFR-TKIs plus Bev. The median age was 63 years, with a majority of recruited female patients. All included individuals had an Eastern Cooperative Oncology Group performance score of 2 or less. The addition of Bev resulted in a significantly higher ORR (94.4% v 40%, P > .001). Median PFS was longer with the use of the combination therapy (11.12 v 7.87 months; P = .001). Median overall survival tended to be longer in the EGFR-TKIs plus Bev (30.9 v 25.4 months; P = .06) but failed to reach statistical significance. Response in terms of both partial and complete as well as overall favorably affected PFS.

CONCLUSION

EGFR-TKIs plus Bev conferred a significantly higher ORR and PFS in advanced NSCLC patients with EGFR mutation and BIMdel. Further prospective studies are needed to validate these findings.

Cytoplasmic P120ctn Promotes Gefitinib Resistance in Lung Cancer Cells by Activating PAK1 and ERK Pathway

Our previous studies indicated that cytoplasmic p120ctn mediated epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKI) resistance in lung cancer. In the present study, we aim to further explore the underlying molecular mechanisms. Immunohistochemistry detected PAK1, Cdc42, and Rac1 expression in lung cancer with cytoplasmic p120ctn. Immunoblotting, protein activity analysis, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide evaluated p120ctn location, PAK1, Cdc42/Rac1, and extracellular signal-regulated kinase (ERK) activity in response to TKI treatment in HCC827 and PC9 cell lines, as well as the cell sensitivity to Gefitinib. Most non-small cell lung cancer patients with cytoplasmic p120ctn showed enhanced PAK1 and Cdc42/Rac1. When Gefitinib resistance was induced, cytoplasmic p120ctn is accompanied with increasing PAK1 and Cdc42/Rac1. Cytoplasmic p120ctn activated ERK via PAK1, while PAK1 downregulation attenuated ERK activation by cytoplasmic p120ctn. After Cdc42/Rac1 inhibition, cytoplasmic p120ctn could not activate PAK1. Cytoplasmic p120ctn activates PAK1 via Cdc42/Rac1 activation, constitutively activates ERK in the EGFR downstream signaling, and promotes EGFR-TKI resistance in lung cancer cells. The current study will aid to screen the subpopulation patients who would benefit from therapy with first-generation EGFR-TKIs.

Modeling restoration of gefitinib efficacy by co-administration of MET inhibitors in an EGFR inhibitor-resistant NSCLC xenograft model: A tumor-in-host DEB-based approach

MET receptor tyrosine kinase inhibitors (TKIs) can restore sensitivity to gefitinib, a TKI targeting epidermal growth factor receptor (EGFR), and promote apoptosis in non-small cell lung cancer (NSCLC) models resistant to gefitinib treatment in vitro and in vivo. Several novel MET inhibitors are currently under study in different phases of development. In this work, a novel tumor-in-host modeling approach, based on the Dynamic Energy Budget (DEB) theory, was proposed and successfully applied to the context of poly-targeted combination therapies. The population DEB-based tumor growth inhibition (TGI) model well-described the effect of gefitinib and of two MET inhibitors, capmatinib and S49076, on both tumor growth and host body weight when administered alone or in combination in an NSCLC mice model involving the gefitinib-resistant tumor line HCC827ER1. The introduction of a synergistic effect in the combination DEB-TGI model allowed to capture gefitinib anticancer activity enhanced by the co-administered MET inhibitor, providing also a quantitative evaluation of the synergistic drug interaction. The model-based comparison of the two MET inhibitors highlighted that S49076 exhibited a greater anticancer effect as well as a greater ability in restoring sensitivity to gefitinib than the competitor capmatinib. In summary, the DEB-based tumor-in-host framework proposed here can be applied to routine combination xenograft experiments, providing an assessment of drug interactions and contributing to rank investigated compounds and to select the optimal combinations, based on both tumor and host body weight dynamics. Thus, the combination tumor-in-host DEB-TGI model can be considered a useful tool in the preclinical development and a significant advance toward better characterization of combination therapies.

Efficacy of EGFR-TKI Plus Chemotherapy or Monotherapy as First-Line Treatment for Advanced EGFR-Mutant Lung Adenocarcinoma Patients With Co-Mutations

Background

Co-mutations was associated with poor response to EGFR-TKIs. First-generation EGFR-TKIs combined with chemotherapy was reported to be more effective than TKIs alone in advanced lung adenocarcinoma patients.

Objective

This retrospective study aimed to explore whether EGFR-mutant patients with co-mutations can benefit from EGFR-TKIs plus chemotherapy.

Patients and Methods

We retrospectively collected data of 137 EGFR-mutant patients with advanced lung adenocarcinoma who underwent next-generation sequencing in our hospital in 2018. Among them, 96 were treated with EGFR–TKIs alone and 41 received EGFR–TKIs plus chemotherapy. We analyzed the progression-free survival (PFS) of patients with co-mutations using different treatments.

Results

Concurrent TP53 mutations, especially exon 4 and 6, were associated with a markedly shorter time to progression on EGFR-TKI monotherapy (11.4 months vs. 16.6 months, P=0.003), while EGFR–TKIs plus chemotherapy would benefit those patients more (with TP53: 11.4 months vs. 19.1 months, P=0.001, HR=0.407; without TP53: 16.6 months vs. 18.9 months, P=0.379, HR=0.706). The incidence of T790M after resistance was equal in patients treated with different treatments (53% vs. 53%, P=0.985).

Conclusions

In our study, concurrent TP53 mutations were found to be risk factors for EGFR-TKI monotherapy, but TKI combined with chemotherapy could eliminate this heterogeneity.

Hype or hope - Can combination therapies with third-generation EGFR-TKIs help overcome acquired resistance and improve outcomes in EGFR-mutant advanced/metastatic NSCLC?

Three generations of epidermal growth factor receptor - tyrosine kinase inhibitors (EGFR-TKIs) have been developed for treating advanced/metastatic non-small cell lung cancer (NSCLC) patients harboring EGFR-activating mutations, while a fourth generation is undergoing preclinical assessment. Although initially effective, acquired resistance to EGFR-TKIs usually arises within a year due to the emergence of clones harboring multiple resistance mechanisms. Therefore, the combination of EGFR-TKIs with other therapeutic agents has emerged as a potential strategy to overcome resistance and improve clinical outcomes. However, results obtained so far are ambiguous and ideal therapies for patients who experience disease progression during treatment with EGFR-TKIs remain elusive. This review provides an updated landscape of EGFR-TKIs, along with a description of the mechanisms causing resistance to these drugs. Moreover, it discusses the current knowledge, limitations, and future perspective regarding the use of EGFR-TKIs in combination with other anticancer agents, supporting the need for bench-to-bedside approaches in selected populations.

Molecular and Functional Analysis of Sunitinib-Resistance Induction in Human Renal Cell Carcinoma Cells

Resistance in clear cell renal cell carcinoma (ccRCC) against sunitinib is a multifaceted process encompassing numerous molecular aberrations. This induces clinical complications, reducing the treatment success. Understanding these aberrations helps us to select an adapted treatment strategy that surpasses resistance mechanisms, reverting the treatment insensitivity. In this regard, we investigated the dominant mechanisms of resistance to sunitinib and validated an optimized multidrug combination to overcome this resistance. Human ccRCC cells were exposed to single or chronic treatment with sunitinib to obtain three resistant clones. Upon manifestation of sunitinib resistance, morphometric changes in the cells were observed. At the molecular level, the production of cell membrane and extracellular matrix components, chemotaxis, and cell cycle progression were dysregulated. Molecules enforcing the cell cycle progression, i.e., cyclin A, B1, and E, were upregulated. Mass spectrometry analysis revealed the intra- and extracellular presence of N-desethyl sunitinib, the active metabolite. Lysosomal sequestration of sunitinib was confirmed. After treatment with a synergistic optimized drug combination, the cell metabolic activity in Caki-1-sunitinib-resistant cells and 3D heterotypic co-cultures was reduced by >80%, remaining inactive in non-cancerous cells. These results demonstrate geno- and phenotypic changes in response to sunitinib treatment upon resistance induction. Mimicking resistance in the laboratory served as a platform to study drug responses.

Combination of two miRNAs has a stronger effect on stimulating apoptosis, inhibiting cell growth, and increasing erlotinib sensitivity relative to single miRNA in A549 lung cancer cells

Despite the dramatic efficacy of EGFR-TKIs, most of non-small cell lung cancer patients ultimately develop resistance to these agents. In this study, we explored the effects of miRNA-125a-5p and miRNA-145, alone or in combination, EGFR expression, cell growth and sensitivity of the NSCLC cells to erlotinib. The expression of EGFR was measured using RT-qPCR and Western blotting. The effect of miRNAs and erlotinib on cell growth and survival was assessed by trypan blue assay and MTT assay, respectively. Apoptosis was measured using ELISA cell death assay. We found that transfection of miRNA-125a-5p and miRNA-145 significantly inhibited the expression of EGFR mRNA and protein in a time-dependent manner (p < 0.05 vs. blank control or negative control miRNA). ANOVA and Bonferroni's test were used to ascertain significant differences between groups. Other experiments indicated that upregulation of each of miRNA-125a-5p or miRNA-145 inhibited cell growth, induced apoptosis, and markedly decreased the IC₅₀ value of erlotinib in A549 lung cancer cells (p < 0.05). Moreover, the combination of two miRNAs showed a stronger effect on cells survival, apoptosis, and drug sensitivity, relative to single miRNA (p < 0.05). The results of our study indicate that the therapeutic delivery of miRNA-145 and miRNA-125a-5p to lung cancer may inhibit cell proliferation, trigger apoptosis, and sensitize lung cancer cells to EGFR-TKIs.

Cyclic RGD Pentapeptide Cilengitide Enhances Efficacy of Gefitinib on TGF-β1-Induced Epithelial-to-Mesenchymal Transition and Invasion in Human Non-Small Cell Lung Cancer Cells

During non-small cell lung cancer (NSCLC) progression, transforming growth factor (TGF)-β mediated epithelial-to-mesenchymal transition (EMT) is an important process leading to high mortality and poor prognosis. The EMT is a fundamental process for morphogenesis characterized by the transformation of cancer cells into invasive forms that can be transferred to other organs during human lung cancer progression. Gefitinib, an epidermal growth factor receptor (EGFR) inhibitor, has shown anti-proliferative effects in EGFR-mutated NSCLC cells and an inhibitory effect on migration and invasion of NSCLC cells to other organs. In this study, we evaluated the combinatorial treatment effect of cilengitide, a cyclic RGD pentapeptide, on TGF-β1-induced EMT phenotype and invasion. Gefitinib suppressed the expression of TGF-β1-induced mesenchymal markers by inhibiting Smad and non-Smad signaling pathways. Cilengitide enhanced the inhibitory effect of gefitinib on TGF-β1-induced expression of mesenchymal markers, phosphorylation of Smad2/3, and invasion of NSCLC A549 cells. We suggested that the use of cilengitide can improve the efficacy of anti-cancer drugs in combination drug-based chemotherapy. These results provide an improved therapeutic strategy for treating and preventing EMT-related disorders, such as NSCLC, lung fibrosis, cancer metastasis, and relapse.

Clinical Potential of Kinase Inhibitors in Combination with Immune Checkpoint Inhibitors for the Treatment of Solid Tumors

Oncogenic kinases contribute to immunosuppression and modulate the tumor microenvironment in solid tumors. Increasing evidence supports the fundamental role of oncogenic kinase signaling networks in coordinating immunosuppressive tumor microenvironments. This has led to numerous studies examining the efficacy of kinase inhibitors in inducing anti-tumor immune responses by increasing tumor immunogenicity. Kinase inhibitors are the second most common FDA-approved group of drugs that are deployed for cancer treatment. With few exceptions, they inevitably lead to intrinsic and/or acquired resistance, particularly in patients with metastatic disease when used as a monotherapy. On the other hand, cancer immunotherapies, including immune checkpoint inhibitors, have revolutionized cancer treatment for malignancies such as melanoma and lung cancer. However, key hurdles remain to successfully incorporate such therapies in the treatment of other solid cancers. Here, we review the recent literature on oncogenic kinases that regulate tumor immunogenicity, immune suppression, and anti-tumor immunity. Furthermore, we discuss current efforts in clinical trials that combine kinase inhibitors and immune checkpoint inhibitors to treat breast cancer and other solid tumors.

Combination of HGF/MET-targeting agents and other therapeutic strategies in cancer

MET receptor has emerged as a druggable target across several human cancers. Agents targeting MET and its ligand hepatocyte growth factor (HGF) including small molecules such as crizotinib, tivantinib and cabozantinib or antibodies including rilotumumab and onartuzumab have proven their values in different tumors. Recently, capmatinib was approved for treatment of metastatic lung cancer with MET exon 14 skipping. In this review, we critically examine the current evidence on how HGF/MET combination therapies may take advantage of synergistic effects, overcome primary or acquired drug resistance, target tumor microenvironment, modulate drug metabolism or tackle pharmacokinetic issues. Preclinical and clinical studies on the combination of HGF/MET-targeted agents with conventional chemotherapeutics or molecularly targeted treatments (including EGFR, VEGFR, HER2, RAF/MEK, and PI3K/Akt targeting agents) and also the value of biomarkers are examined. Our deeper understanding of molecular mechanisms underlying successful pharmacological combinations is crucial to find the best personalized treatment regimens for cancer patients.

Detection of Low-Frequency KRAS Mutations in cfDNA From EGFR-Mutated NSCLC Patients After First-Line EGFR Tyrosine Kinase Inhibitors

Background

Molecular profiling of advanced EGFR mutated NSCLC has recently demonstrated the co-existence of multiple genetic alterations. Specifically, co-existing KRAS-mutations in EGFR NSCLCs have been described, despite their prevalence at progression and their role in the response to EGFR tyrosine kinase inhibitors (TKIs) remain marginally explored. Aim of our study was to investigate the prevalence of co-existing KRAS mutations at the time of progressive disease and explore their impact on clinical outcome.

Materials and Methods

We retrospectively analyzed by digital droplet PCR prevalence of KRAS co-mutations in 106 plasma samples of EGFR mutated NSCLC patients, in progressive disease after EGFR TKI treatment as first-line therapy.

Results

KRAS co-mutations (codon 12 and 13) were identified in 3 patients (2.8% of analyzed samples), with low allelic frequency (<0.2%), and had a negative impact on clinical outcome to first-line EGFR TKI.

Conclusion

Detection of KRAS mutations in cell-free DNA of EGFR mutant NSCLC patients at progression after first or second generation EGFR TKI is a rare event. Due to their low abundance, the negative impact of KRAS mutations on the response to EGFR TKI remains to be confirmed in larger studies.

In vitro and in vivo Study of a Novel Liposome-Mediated Dual Drug Delivery for Synergistic Lung Cancer Therapy via Oral Administration

Background

To establish the co-delivery liposomes of gefitinib (GFT) and curcumin (CUR) via oral administration with the goals of improving the synergistic effect and reducing acquired drug resistance.

Methods

We prepared liposomes (LPs) which can embed the anticancer compound GFT and CUR and investigated whether they could enhance the antitumor effects of anticancer drugs against MDR. The LPs system was characterized by transmission electron microscopy (TEM), particle size, encapsulation efficiency, cellular uptake and cell viability. In addition, the release characteristics and pharmacodynamics of the LPs were also studied in detail.

Results

The results showed that GFT/CUR LPs were characterized by small particle size of about 130 nm and negative zeta potential of about −22.2 mV, and the drug controlled to release slowly on a biphasic pattern. Compared with control groups, GFT/CUR LPs showed a higher cellular uptake and cell inhibition rates. Through pharmacodynamics analysis, we found that two compounds (GFT and CUR) were incorporated into one LPs carrier, which played a good role in synergistic effect.

Conclusion

Co-delivery of GFT and CUR has the potential to improve cancer treatment efficacy and overcome acquired resistance, especially towards GFT-resistant cells.

Cyclic pentapeptide cRGDfK enhances the inhibitory effect of sunitinib on TGF-β1-induced epithelial-to-mesenchymal transition in human non-small cell lung cancer cells

In human lung cancer progression, the EMT process is characterized by the transformation of cancer cells into invasive forms that migrate to other organs. Targeting to EMT-related molecules is emerging as a novel therapeutic approach for the prevention of lung cancer cell migration and invasion. Traf2- and Nck-interacting kinase (TNIK) has recently been considered as an anti-proliferative target molecule to regulate the Wnt signaling pathway in several types of cancer cells. In the present study, we evaluated the inhibitory effect of a tyrosine kinase inhibitor sunitinib and the integrin-α_Ⅴβ₃ targeted cyclic peptide (cRGDfK) on EMT in human lung cancer cells. Sunitinib strongly inhibited the TGF-β1-activated EMT through suppression of Wnt signaling, Smad and non-Smad signaling pathways. In addition, the cRGDfK also inhibited the expression of TGFβ1-induced mesenchymal marker genes and proteins. The anti-EMT effect of sunitinib was enhanced when cRGDfK was treated together. When sunitinib was treated with cRGDfK, the mRNA and protein expression levels of mesenchymal markers were decreased compared to the treatment with sunitinib alone. Co-treatment of cRGDfK has shown the potential to improve the efficacy of anticancer agents in combination with therapeutic agents that may be toxic at high concentrations. These results provide new and improved therapies for treating and preventing EMT-related disorders, such as lung fibrosis and cancer metastasis, and relapse.

Fluoropyrimidin-2,4-dihydroxy-5-isopropylbenzamides as antitumor agents against CRC and NSCLC cancer cells

A major cause of failure of therapy in patients with non-small cell lung cancer (NSCLC) is development of acquired drug resistance leading to tumor recurrence and disease progression. In addition to the development of new generations of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs), different molecular targets may provide opportunities to improve the therapeutic outcomes. In this study, we utilized the core structure 5-fluorouracil (5-FU) or tegafur, a 5-FU prodrug combined through different linkers with resorcinol to generate a series of fluoropyrimidin-2,4-dihydroxy-5-isopropylbenzamides which inhibit potent Heat Shock Protein 90 (HSP90). These compounds were found to show significant antiproliferative activity in colorectal cancer (CRC) HCT116 and NSCLC A549, H460, and H1975 (EGFR L858R/T790 M double mutation) cells. Compound 12c, developed by molecular docking analysis and enzymatic assays exhibits promising inhibitory activity of HSP90. This compound, 12c shows the most potent HSP90 inhibitory activity with an IC₅₀ value of 27.8 ± 4.4 nM, superior to that of reference compounds AUY-922 (Luminespib) and BIIB021 whose IC₅₀ values are 43.0 ± 0.9 nM and 56.8 ± 4.0 nM respectively. This strong HSP90 inhibitory activity of 12c leads to rapid degradation of client proteins EGFR and Akt in NSCLC cells. In addition, 12c induces significant accumulation of a sub-G1 phase population in parallel with apoptosis by showing activated caspase-3, -8 and -9 and PARP induction. These results provide a new strategy for development of novel HSP90 inhibitors for cancer treatment.

Synthesis and biological evaluation of quinoxaline derivatives as specific c-Met kinase inhibitors

A series of novel quinoxaline derivatives were synthesized and evaluated for their inhibitory activity against c-Met kinase enzyme. Most of the tested compounds exhibited potent inhibitory activity. All the synthesized quinoxaline compounds were further examined against c-Met overexpressed human gastric cancer cell line (MKN-45), which showed good inhibitory activity. Among the synthesized compounds, compound 4 exhibited better tumor growth inhibition in the animal model study; we also confirmed its acceptable drug property and highly selective target activity.

A Phase III, randomized, double-blind, placebo-controlled, multicenter study of fruquintinib in Chinese patients with advanced nonsquamous non-small-cell lung cancer - The FALUCA study

OBJECTIVES

Fruquintinib is an orally active kinase inhibitor that selectively targets the vascular endothelial growth factor (VEGF) receptor. A Phase II trial has demonstrated a significant benefit in progression-free survival (PFS) for fruquintinib-treated patients with locally advanced/metastatic nonsquamous non-small-cell lung cancer (NSCLC) who have progressed after second-line chemotherapy. This Phase III trial is a randomized, double-blind, multicenter trial to confirm fruquintinib's efficacy in the same patient population.

MATERIALS AND METHODS

From December 2015 to February 2018, 730 patients were screened, of whom 527 were enrolled into the study. Participants were randomized 2:1 to receive fruquintinib (n = 354) or placebo (n = 173) once daily for 3 weeks on-treatment, and 1 week off-treatment. Patients were stratified according to epidermal growth factor receptor mutation status and prior use of VEGF inhibitors. Primary endpoint was overall survival (OS).

RESULTS

Median OS was 8.9 months for the fruquintinib group and 10.4 months for placebo group (hazard ratio [HR] 1.02; 95 % confidence interval [CI], 0.82-1.28; P = 0.841), with median PFS of 3.7 months and 1.0 months, respectively (HR 0.34; 95 % CI, 0.28-0.43; P < 0.001). Objective response rate and disease control rate were 13.8 % and 66.7 % for fruquintinib, and 0.6 % and 24.9 % for placebo, respectively (P < 0.001). Hypertension was the most frequent treatment-emergent adverse event (≥grade 3) observed in fruquintinib-treated patients (21.0 %). Post hoc analysis revealed that fruquintinib prolonged the median OS for patients who did not receive subsequent antitumor therapy: 7.0 months versus 5.1 months for placebo (HR 0.65; 95 % CI, 0.46-0.91; P = 0.012). Patients receiving fruquintinib also reported improvements in quality of life for most functional scales measured by EORTC QLQ-C30 and LC13 questionnaires.

CONCLUSION

Although the study did not meet its primary endpoint, fruquintinib could be effective in combination with other agents for the treatment of patients with NSCLC who have failed second-line chemotherapy.

High-level gain of mesenchymal-epithelial transition factor (MET) copy number using next-generation sequencing as a predictive biomarker for MET inhibitor efficacy

Background

In clinical oncology, targeted next-generation sequencing (NGS) has become an integral part of the routine molecular diagnostics repertoire. However, a consensus is yet to be agreed on the optimal mesenchymal-epithelial transition factor (MET) copy number (CN) cut-off value based on NGS data that could predict the MET-amplified non-small cell lung cancer (NSCLC) patients who could benefit from MET tyrosine kinase inhibitor (TKI) therapy. In this study, we aimed to identify the criteria to define MET amplification derived from NGS data.

Methods

Sequencing data from matched plasma and tissue samples from 40 MET-amplified NSCLC patients were used to derive a normalization method, referred to as adjusted copy number (adCN). Clinical outcomes from an additional 18 MET TKI-treated NSCLC patients with solely MET-amplified cancers were analyzed to validate the adCN cut-offs.

Results

AdCN, calculated as the absolute CN generated from NGS relative to the maximum mutant allele fraction (maxMAF) per sample, was demonstrated to have a high correlation with MET CN in tissue and plasma samples (R²=0.73). Using a cut-off value of 5.5 and 13, tertile stratification of adCN was able to distinguish patients with high-level MET amplification. The MET TKI-treated patients with adCN >13, categorized as high-level amplification, had significantly longer progression-free survival (PFS) than those with adCN <13 (P=0.009), suggesting that adCN positively correlated with the response to MET TKI.

Conclusions

We derived a normalization method that could reflect the relative CN and distinguish MET-amplified NSCLC patients with high-level gene amplification who were sensitive to crizotinib, suggesting adCN could potentially serve as a predictive biomarker for MET TKI response.

Identification of low-dose multidrug combinations for sunitinib-naive and pre-treated renal cell carcinoma

Background

Combinations of drugs can improve the efficacy of cancer treatment, enable the reduction of side effects and the occurrence of acquired drug resistance.

Methods

We approached this challenge mathematically by using the validated technology called the Therapeutically Guided Multidrug Optimization (TGMO) method. In a set of genetically distinct human renal cell carcinoma (RCC) cell lines, either treated chronically with sunitinib (−ST) or sunitinib-naive, we identified cell line-specific low-dose-optimised drug combinations (ODC).

Results

Six cell-type-specific low-dose drug combinations for three sunitinib-naive as well as three sunitinib pre-treated cells were established. These ODCs effectively inhibited the RCC cell metabolic activity while being ineffective in non-cancerous cells. Based on a single screening test and three searches, starting with ten drugs, we identified highly efficacious drug mixtures containing four drugs. All ODCs contained AZD4547 (FGFR signalling pathway inhibitor) and pictilisib (pan-phosphatidylinositol 3-kinase inhibitor), but varied in the third and fourth drug. ODC treatment significantly decreased cell metabolic activity (up to 70%) and induced apoptosis, independent of the pretreatment with sunitinib. The ODCs outperformed sunitinib, the standard care for RCC. Moreover, short-term starvation potentiated the ODC activity. The translation of the 2D-based results to 3D heterotypic co-culture models revealed significant inhibition of the spheroid growth (up to 95%).

Conclusion

We demonstrate a promising low-dose drug combination development to obtain drug combinations effective in naive as well as resistant tumours. Nevertheless, we emphasise the need for further mechanistic investigation and preclinical development.

Cisplatin treatment induced interleukin 6 and 8 production alters lung adenocarcinoma cell migration in an oncogenic mutation dependent manner

BACKGROUND

The predominant metastatic site of lung cancer (LC) is the brain. Although outdated, conventional cisplatin treatment is still the main therapeutic approach for patients with advanced non-small cell lung cancer (NSCLC), since targeted therapy that offers better tumor control is not always possible. In the present study brain metastasis associated cytokine expression was investigated in primary NSCLC adenocarcinoma (AC) tissues with known oncogenic mutations in the presence or absence of platina based and tyrosine kinase inhibitor (TKI) drugs.

METHODS

Primary lung tumor samples were isolated, DNA was sequenced and then the samples were grouped based on mutation. Experiments were also performed using KRAS mutant A549 and EGFR mutant PC-9 cells. Drug response was analyzed in three dimensional (3D) tissue cultures. We assessed drug response and IL-6 and IL-8 cytokine expression in relation to cellular invasion using ATP dependent cell viability, qRT-PCR analysis, cytokine bead array, and migration assay.

RESULTS

In 3D co-cultures, primary NSCLC derived cells harboring EGFR mutation responded better to erlotinib treatment than KRAS mutant or KRAS/EGFR wild type (WT) cancer cells. In contrast, under the same culture conditions KRAS/EGFR WT or KRAS mutant cancer cells are more sensitive to cisplatin than EGFR mutant cells. Drug response and pro-inflammatory cytokine production varied depending on the driver mutations. Cisplatin but not erlotinib increased both IL-6 and IL-8 secretion and only IL-6 increased cellular migration and proliferation.

CONCLUSION

In vitro assays are available to determine the response to planned therapeutic approach of lung cancer subtypes. The sequence of administration of therapeutic drugs determines cytokine production and therefore therapeutic response.