Osimertinib: A Review in T790M-Positive Advanced Non-Small Cell Lung Cancer

Electrochemiluminescent CdS Quantum Dots Biosensor for Cancer Mutation Detection at Different Positions on Linear DNA Analytes

PCR-based techniques routinely employed for the detection of mutated linear DNA molecules, including circulating tumor DNA (ctDNA), require large nucleotide sections on both sides of the mutation for primer annealing. This means that DNA fragments with a mutation positioned closer to the extremities are unlikely to be detected. Thus, sensors capable of recognizing linear DNA with characteristic mutations closer to the ends would be advantageous over the state-of-the-art approaches. Here, an electrochemiluminescence-resonance energy transfer (ECL-RET) biosensor comprising capped CdS quantum dots and hairpin DNA probes labeled with Au nanoparticles was developed for the detection of epidermal growth factor receptor (EGFR) ctDNA carrying the critical T790M lung cancer mutation. The ECL-RET system detected different DNA molecules including single-stranded 18-nucleotides (nt) and 40-nt as well as double-stranded 100-nt with the single nucleotide polymorphism (SNP) coding for T790M located either in the middle or only 7 nt from one end. For all target DNA, the sensor's limits of detection (LODs) were in the aM range, with excellent selectivity. It was the case of 100-nt target linear ctDNA fragments with LODs of 8.1 and 3.4 aM when the EGFR T790M SNP was either in the middle or at the end, respectively. These results show that ECL-RET systems can sense mutations in DNA fragments that would remain undetected by standard techniques.

Neoadjuvant Osimertinib Followed by Sequential Definitive Radiation Therapy and/or Surgery in Stage III Epidermal Growth Factor Receptor-Mutant Non-Small Cell Lung Cancer: An Open-Label, Single-Arm, Phase 2 Study

PURPOSE

The treatment for unresectable, locally advanced stage III non-small cell lung cancer (NSCLC) is concurrent chemoradiation therapy (CRT) followed by consolidation durvalumab. This study aimed to evaluate the benefit of neoadjuvant osimertinib as an alternative therapy to this approach with the aim of reducing the radiation field.

METHODS AND MATERIALS

This investigation was a nonrandomized, open-label, single-arm, phase 2, prospective, proof-of-concept study. Eligible patients were classified as having treatment-naïve, nonoperable, stage III epidermal growth factor receptor-mutant NSCLC. Patients received 80 mg of oral osimertinib daily for 12 weeks before definitive radiation therapy (RT) and/or surgery. The response was assessed at weeks 6 and 12. For responders, sequential definitive RT and/or surgery were planned. Nonresponders were started on standard CRT. After RT ± surgery or CRT, patients were followed for 2 years without adjuvant therapy. The primary endpoint was the objective response rate (ORR), with September 20, 2022, set as the cut-off for data collection. Secondary endpoints were safety and the gross tumor volume (GTV), planned tumor volume (PTV), and the percentage of total lung volume minus GTV exceeding 20 Gy (V20%) before versus after osimertinib. Exploratory analyses included assessments of the presence of plasma circulating tumor-free DNA (ctDNA) before osimertinib treatment, at weeks 6 and 12, at the end of RT, and 6 weeks post-RT.

RESULTS

Twenty-four patients were included (19 women; median age, 73 years; range, 51-82 years). Nineteen of 24 had never smoked, 20 of 24 had adenocarcinoma, 16 of 24 had exon 19 deletions, and 8 of 24 had exon 21 mutations. Participants had stage IIIA (10), IIIB (9), or IIIC (5) disease. Three patients were excluded from the analysis (1 dropped out and 2 were still undergoing osimertinib treatment at the cut-off date). The ORR to induction osimertinib was 95.2% (17 partial response, 3 complete response, and 1 progressive disease). After induction osimertinib, 13 of 20 patients were definitively radiated, 3 of 20 underwent surgery, and 5 of 20 were excluded. Four patients were restaged as stage IV (contralateral ground-glass opacities responded to osimertinib), and 1 patient withdrew informed consent. Three patients underwent surgery, one of whom was treated with RT. Two patients achieved pT1aN0, and one achieved pathologic complete response. The median GTV, PTV, and V20% before osimertinib treatment were 47.4 ± 76.9 cm3 (13.5-234.9), 227.0 ± 258.8 cm3 (77.8-929.2), and 27.1 ± 16.4% (6.2-60.3), respectively. The values after osimertinib treatment were 27.5 ± 42.3 cm3 (2.99-137.7; -48 ± 20%; P = .02), 181.9 ±198.4 cm3 (54-718.1; -31 ± 20%; P = .01), and 21.8 ± 11.7% (9.1-44.15; -24 ± 40%; P = .04), respectively. PTV/GTV/V20% reduction was associated with tumor size and central location. The median follow-up time was 28.71 months (range, 0.4-45.1 months), and median disease-free survival was not reached (mean, 30.59; standard error, 3.94; 95% confidence interval, 22.86-38.31). ctDNA was detected in 5 patients; 4 of 5 were positive for ctDNA at baseline and became negative during osimertinib induction but were again positive after osimertinib treatment was terminated. Interestingly, 3 patients who were ctDNA negative at baseline became weakly positive after RT and then were negative at follow-up. No significant adverse events were reported during the osimertinib or radiation phases.

CONCLUSIONS

Neoadjuvant osimertinib therapy is feasible in patients with stage III lung cancer NSCLC, followed by definitive radiation and/or surgery, with an ORR of 95.2% and an excellent safety profile. Osimertinib induction for 12 weeks before definitive radiation (chemo-free) significantly reduced the radiation field by nearly 50% with a linear association with tumor size. Further studies are needed to test this chemo-free approach for long-term outcomes before practices are changed.

Harnessing systematic protein-ligand interaction fingerprints for drug discovery

Determining protein-ligand interaction characteristics and mechanisms is crucial to the drug discovery process. Here, we review recent progress and successful applications of a systematic protein-ligand interaction fingerprint (IFP) approach for investigating proteome-wide protein-ligand interactions for drug development. Specifically, we review the use of this IFP approach for revealing polypharmacology across the kinome, predicting promising targets from which to design allosteric inhibitors and covalent kinase inhibitors, uncovering the binding mechanisms of drugs of interest, and demonstrating resistant mechanisms of specific drugs. Together, we demonstrate that the IFP strategy is efficient and practical for drug design research for protein kinases as targets and is extensible to other protein families.

Osimertinib: A Review in Completely Resected, Early-Stage, EGFR Mutation-Positive NSCLC

Osimertinib (TAGRISSO^®) is an orally administered, third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor that is approved for the adjuvant treatment of adults with completely resected, stage IB-IIIA, EGFR sensitizing mutation (exon 19 deletion or exon 21 [L858R] substitution)-positive non-small cell lung cancer (NSCLC). In the pivotal ADAURA trial in adults with completely resected, early-stage, EGFR mutation-positive (EGFRm+) NSCLC, osimertinib adjuvant therapy significantly prolonged disease-free survival (DFS) compared with placebo in the overall population of patients with stage IB-IIIA disease, as well as in the primary population of patients with stage II-IIIA disease. A DFS benefit of osimertinib was seen irrespective of whether or not patients received prior adjuvant chemotherapy. Overall survival (OS) data were very immature at the time of the analysis of DFS, and more mature OS data are awaited with interest. Osimertinib adjuvant therapy did not adversely affect health-related quality of life and was generally well tolerated, with a manageable safety profile and no new safety signals identified. Based on the available evidence, osimertinib is thus an appropriate targeted option for the adjuvant treatment of adults with completely resected, stage IB-IIIA, EGFRm+ NSCLC.

Aumolertinib: A Review in Non-Small Cell Lung Cancer

Aumolertinib (formerly almonertinib; Ameile^®) is an oral, third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (EGFR-TKI) that is selective for mutant EGFR over wild-type EGFR. It has been developed for the treatment of advanced EGFR mutation-positive non-small cell lung cancer (NSCLC). In the phase 3 AENEAS trial conducted in Chinese patients, aumolertinib as first-line treatment significantly prolonged progression-free survival (PFS) and duration of response (DoR) compared with gefitinib in patients with advanced EGFR mutation-positive NSCLC; overall survival (OS) data from this study are immature. In the phase 1/2 APOLLO trial, aumolertinib showed good clinical activity (based on objective response rate, PFS, DoR and OS) in Chinese patients with locally advanced or metastatic EGFR T790M mutation-positive NSCLC who had progressed on or after prior EGFR-TKI therapy. Aumolertinib has a generally manageable tolerability profile; adverse events associated with wild-type EGFR inhibition (e.g. rash and diarrhoea) were less frequent with aumolertinib than gefitinib in AENEAS. Thus, aumolertinib is a promising new option for both first-line and second-line treatment in patients with advanced EGFR mutation-positive NSCLC.

Molecular hybrids: A five-year survey on structures of multiple targeted hybrids of protein kinase inhibitors for cancer therapy

Protein kinases have grown over the past few years as a crucial target for different cancer types. With the multifactorial nature of cancer, and the fast development of drug resistance for conventional chemotherapeutics, a strategy for designing multi-target agents was suggested to potentially increase drug efficacy, minimize side effects and retain the proper pharmacokinetic properties. Kinase inhibitors were used extensively in such strategy. Different kinase inhibitor agents which target EGFR, VEGFR, c-Met, CDK, PDK and other targets were merged into hybrids with conventional chemotherapeutics such as tubulin polymerization and topoisomerase inhibitors. Other hybrids were designed gathering kinase inhibitors with targeted cancer therapy such as HDAC, PARP, HSP 90 inhibitors. Nitric oxide donor molecules were also merged with kinase inhibitors for cancer therapy. The current review presents the hybrids designed in the past five years discussing their design principles, results and highlights their future perspectives.

Small Molecule Kinase Inhibitor Drugs (1995-2021): Medical Indication, Pharmacology, and Synthesis

The central role of dysregulated kinase activity in the etiology of progressive disorders, including cancer, has fostered incremental efforts on drug discovery programs over the past 40 years. As a result, kinase inhibitors are today one of the most important classes of drugs. The FDA approved 73 small molecule kinase inhibitor drugs until September 2021, and additional inhibitors were approved by other regulatory agencies during that time. To complement the published literature on clinical kinase inhibitors, we have prepared a review that recaps this large data set into an accessible format for the medicinal chemistry community. Along with the therapeutic and pharmacological properties of each kinase inhibitor approved across the world until 2020, we provide the synthesis routes originally used during the discovery phase, many of which were only available in patent applications. In the last section, we also provide an update on kinase inhibitor drugs approved in 2021.

Osimertinib: A Review in Previously Untreated, EGFR Mutation-Positive, Advanced NSCLC

Activating mutations in the epidermal growth factor receptor (EGFR) gene have been identified as key oncogenic drivers of non-small cell lung cancer (NSCLC). Osimertinib (Tagrisso^®) is an orally administered, third-generation EGFR tyrosine kinase inhibitor (EGFR-TKI) that is widely approved for the first-line treatment of advanced NSCLC with activating EGFR mutations. In the pivotal phase III FLAURA trial, osimertinib significantly prolonged progression-free survival (PFS) and overall survival (OS) relative to first-generation EGFR-TKIs in patients with previously untreated, EGFR mutation-positive, advanced NSCLC. Osimertinib also significantly prolonged central nervous system (CNS) PFS in patients with CNS metastases at trial entry. Osimertinib had a generally manageable tolerability profile; the majority of adverse events considered to be possibly related to treatment were of mild to moderate severity. Osimertinib represents a valuable targeted therapeutic for use in adults with previously untreated, EGFR mutation-positive, advanced NSCLC.

The synthesis review of the approved tyrosine kinase inhibitors for anticancer therapy in 2015-2020

In the 21st century, cancer is the major public health problem worldwide. Based on the important roles of protein tyrosine kinase, the accelerated hunt for potent small-molecule tyrosine kinase inhibitors has led to the success of 30 newly inhibitors in this family for the cancer therapy in last five years. In this review, we updated their synthesis methods, and compared the original research routes with the optimized routes for each PTK inhibitor against different target, in order to make an outlook on the future synthesis of potential PTK inhibitors for anticancer therapy.

OPALS: A New Osimertinib Adjunctive Treatment of Lung Adenocarcinoma or Glioblastoma Using Five Repurposed Drugs

Background: Pharmacological targeting aberrant activation of epidermal growth factor receptor tyrosine kinase signaling is an established approach to treating lung adenocarcinoma. Osimertinib is a tyrosine kinase approved and effective in treating lung adenocarcinomas that have one of several common activating mutations in epidermal growth factor receptor. The emergence of resistance to osimertinib after a year or two is the rule. We developed a five-drug adjuvant regimen designed to increase osimertinib’s growth inhibition and thereby delay the development of resistance. Areas of Uncertainty: Although the assembled preclinical data is strong, preclinical data and the following clinical trial results can be discrepant. The safety of OPALS drugs when used individually is excellent. We have no data from humans on their tolerability when used as an ensemble. That there is no data from the individual drugs to suspect problematic interaction does not exclude the possibility. Data Sources: All relevant PubMed.org articles on the OPALS drugs and corresponding pathophysiology of lung adenocarcinoma and glioblastoma were reviewed. Therapeutic Opinion: The five drugs of OPALS are in wide use in general medicine for non-oncology indications. OPALS uses the anti-protozoal drug pyrimethamine, the antihistamine cyproheptadine, the antibiotic azithromycin, the antihistamine loratadine, and the potassium sparing diuretic spironolactone. We show how these inexpensive and generically available drugs intersect with and inhibit lung adenocarcinoma growth drive. We also review data showing that both OPALS adjuvant drugs and osimertinib have data showing they may be active in suppressing glioblastoma growth.

An update of new small-molecule anticancer drugs approved from 2015 to 2020

A high incidence of cancer has given rise to the development of more anti-tumor drugs. From 2015 to 2020, fifty-six new small-molecule anticancer drugs, divided into ten categories according to their anti-tumor target activities, have been approved. These include TKIs (30 drugs), MAPK inhibitors (3 drugs), CDK inhibitors (3 drugs), PARP inhibitors (3 drugs), PI3K inhibitors (3 drugs), SMO receptor antagonists (2 drugs), AR antagonists (2 drugs), SSTR inhibitors (2 drugs), IDH inhibitors (2 drugs) and others (6 drugs). Among them, PTK inhibitors (30/56) have led to a paradigm shift in cancer treatment with less toxicity and more potency. Each of their structures, approval statuses, applications, SAR analyses, and original research synthesis routes have been summarized, giving us a more comprehensive map for further efforts to design more specific targeted agents for reducing cancer in the future. We believe this review will help further research of potential antitumor agents in clinical usage.

Effects of rifampicin on the pharmacokinetics of alflutinib, a selective third-generation EGFR kinase inhibitor, and its metabolite AST5902 in healthy volunteers

Background Alflutinib is a novel irreversible and highly selective third-generation EGFR inhibitor currently being developed for the treatment of non-small cell lung cancer patients with activating EGFR mutations and EGFR T790M drug-resistant mutation. Alflutinib is mainly metabolized via CYP3A4 to form its active metabolite AST5902. Both alflutinib and AST5902 contribute to the in vivo pharmacological activity. The aim of this study was to investigate the effects of rifampicin (a strong CYP3A4 inducer) on the pharmacokinetics of alflutinib and AST5902 in healthy volunteers, thus providing important information for drug-drug interaction evaluation and guiding clinical usage. Methods This study was designed as a single-center, open-label, and single-sequence trial over two periods. The volunteers received a single dose of 80 mg alflutinib on Day 1/22 and continuous doses of 0.6 g rifampicin on Day 15-30. Blood sampling was conducted on Day 1-10 and Day 22-31. The pharmacokinetics of alflutinib, AST5902, and the total active ingredients (alflutinib and AST5902) with or without rifampicin co-administration were respectively analyzed. Results Co-administration with rifampicin led to 86% and 60% decreases in alflutinib AUC_0-∞ and C_max, respectively, as well as 17% decrease in AST5902 AUC_0-∞ and 1.09-fold increase in AST5902 C_max. The total active ingredients (alflutinib and AST5902) exhibited 62% and 39% decreases in AUC_0-∞ and C_max, respectively. Conclusions As a strong CYP3A4 inducer, rifampicin exerted significant effects on the pharmacokinetics of alflutinib and the total active ingredients (alflutinib and AST5902). The results suggested that concomitant strong CYP3A4 inducers should be avoided during alflutinib treatment. This trial was registered at http://www.chinadrugtrials.org.cn . The registration No. is CTR20191562, and the date of registration is 2019-09-12.

Efficacy of the CDK7 Inhibitor on EMT-Associated Resistance to 3rd Generation EGFR-TKIs in Non-Small Cell Lung Cancer Cell Lines

Epithelial to mesenchymal transition (EMT) is associated with resistance during EGFR tyrosine kinase inhibitor (EGFR-TKI) therapy. Here, we investigated whether EMT is associated with acquired resistance to 3rd generation EGFR-TKIs, and we explored the effects of cyclin-dependent kinase 7 (CDK7) inhibitors on EMT-mediated EGFR-TKIs resistance in non-small cell lung cancer (NSCLC). We established 3rd generation EGFR-TKI resistant cell lines (H1975/WR and H1975/OR) via repeated exposure to WZ4002 and osimertinib. The two resistant cell lines showed phenotypic changes to a spindle-cell shape, had a reduction of epithelial marker proteins, an induction of vimentin expression, and enhanced cellular mobility. The EMT-related resistant cells had higher sensitivity to THZ1 than the parental cells, although THZ1 treatment did not inhibit EGFR activity. This phenomenon was also observed in TGF-β1 induced EMT cell lines. THZ1 treatment induced G2/M cell cycle arrest and apoptosis in all of the cell lines. In addition, THZ1 treatment led to drug-tolerant, EMT-related resistant cells, and these THZ1-tolerant cells partially recovered their sensitivity to 3rd generation EGFR-TKIs. Taken together, EMT was associated with acquired resistance to 3rd generation EGFR-TKIs, and CDK7 inhibitors could potentially be used as a therapeutic strategy to overcome EMT associated EGFR-TKI resistance in NSCLC.

New Target Therapies in Advanced Non-Small Cell Lung Cancer: A Review of the Literature and Future Perspectives

Introduction: Lung cancer (LC) is the most common neoplasm worldwide, and 85% of these tumors are classified as non-small cell lung cancer (NSCLC). LC treatment was initially restricted to cytotoxic chemotherapy—platinum compounds associated with 3rd generation cytotoxic agents (paclitaxel, gemcitabine, pemetrexed) and, more recently, with monoclonal antibodies (bevacizumab, ramucirumab). Advancements in treatment are correlated with prolonged overall survival (OS). Current advances are focused on target therapies. Target agents: Anti-epidermal growth factor receptor (EGFR) therapy consists of 1st and 2nd generation tyrosine kinase inhibitors (TKIs such as erlotinib, afatinib). In 60% of cases, resistance to these TKIs occurs due to T790M mutation in EGFR, which is overcome 3rd generation drugs (osimertinib). Anaplastic lymphoma kinase (ALK) is the target for drugs such as crizotinib, alectinib, ceritinib. Programmed death 1 (PD-1) and its ligand serve as targets for immunotherapy agents such as pembrolizumab, nivolumab, atezolizumab. Discussion: Challenges in NSCLC treatment include resistance to 3rd generation TKIs, the high cost of ALK inhibitors, and the need for further research on new drugs.

Desmoglein-2 modulates tumor progression and osimertinib drug resistance through the EGFR/Src/PAK1 pathway in lung adenocarcinoma

Desmoglein-2 (DSG2), a member of the cadherin superfamily, has been implicated in cell-cell adhesion and tumorigenesis. Here, we demonstrate that high DSG2 expression in both lung adenocarcinoma (LUAD) cell lines and tissues is associated with poor prognosis in LUAD patients. Notably, DSG2 overexpression promoted cell proliferation and migration, and increased resistance to the EGFR tyrosine kinase inhibitor osimertinib, whereas DSG2 silencing could reverse these results. Moreover, direct interaction between DSG2 and EGFR in the cell membrane stimulated EGFR signaling to promote tumorigenesis, and loss of DSG2 resulted in EGFR translocation into the cytoplasm. In addition, DSG2 was required for EGFR binding to Src; consequently, DSG2 silencing inhibited tumor cell malignancy via suppression of the EGFR-Src-Rac1-PAK1 signaling pathway. Consistent with these findings, a nude mouse xenograft model using H1975 cells demonstrated that DSG2 promoted LUAD cell growth in vivo and increased osimertinib resistance. Collectively, these observations are the first to elucidate a unique role for DSG2 in the development and progression of lung adenocarcinoma via EGFR signaling.

Potential mechanism of primary resistance to icotinib in patients with advanced non-small cell lung cancer harboring uncommon mutant epidermal growth factor receptor: A multi-center study

The incidence of epidermal growth factor receptor uncommon mutation (EGFRum) is relatively low and patients harboring EGFRum are resistant to the first-generation tyrosine kinase inhibitors (TKI). However, the mechanism of primary resistance remains unclear. Medical records of 98 patients who had never been treated by TKI and who accepted icotinib treatment were collected and followed. The circulating tumor DNA (ctDNA) were detected and analyzed using the next-generation sequencing (NGS) platform after progression on icotinib. The potential primary resistance mechanism of icotinib was explored. A total of 21 (21.4%) and 48 (49%) patients developed primary and acquired resistance to icotinib, respectively. The median progression-free survival (PFS) of primary resistance patients was 1.8 months (0.5-2.3, 95% CI = 1.50-2.10). Before treatment, 52.4% (11/21) of patients carried S768I, 23.8% (5/21) L861Q, 14.3% (3/21) G719X and 14.3% (3/21) exon 20-ins mutations. Approximately 23.8% (5/21) of patients harbored the combined pattern mutations and 76.2% (16/21) of patients harbored the single pattern mutations. The combined pattern with EGFR classical mutation (EGFRcm) had worse PFS than the combined with EGFRum and single pattern (P < .05). There were 6 (28.57%) patients with acquired EGFR extracellular domain mutation, 5 (23.81%) with BCL2L11 loss (BIM deletion polymorphism), 3 (14.29%) with MET amplification, 1 (4.76%) with ERBB2 amplification, 1 (4.76%) with MYC amplification, 1 (4.76%) with PTEN mutation, 1 (4.76%) with PIK3CA mutation and 3 (14.29%) with unknown status. EGFR extracellular domain mutation, BCL2L11 loss, PI3K-AKT-mTOR signaling pathway (PTEN and PIK3CA mutations), MET amplification, ERBB2 amplification or MYC amplification might contribute to molecular mechanisms of primary resistance to icotinib in patients with advanced non-small cell lung cancer harboring uncommon mutant epidermal growth factor receptor. Combined targeted therapy or chemotherapy should be considered in this population.

Mechanisms of acquired tumor drug resistance

Systemic therapy often results in the reduction of tumor size but rarely succeeds in eradicating all cancer cells. Drug efflux, persistence of cancer stem cells (CSCs), epithelial-mesenchymal transition (EMT) and down-regulation of apoptosis are the most known general causes of therapy failure. Tumor escape from targeted compounds often involves pathway-specific mechanisms, which result in the restoration of the affected signaling cascade. The acquisition of drug resistance is mediated by mutations, changes in gene expression, alternative splicing, post-translational protein modifications, etc. Development of resistance to therapy may not necessary involve the emergence of new tumor clones: multiple studies demonstrate that even chemonaive neoplasms already have a small population of cells, which are capable of surviving therapeutic pressure and facilitating the disease progression. Use of combinations of cancer drugs, sequential therapy, adaptive therapy and topical ablation of drug-resistant malignant lumps may help to prolong the time to treatment failure. Many studies on mechanisms of drug resistance rely on the use of cell cultures and animal models. The development of approaches that allow efficient monitoring of the evolution of tumor phenotype in clinical setting presents a challenge.

Targeted therapies for non-HPV-related head and neck cancer: challenges and opportunities in the context of predictive, preventive, and personalized medicine

Head and neck squamous cell carcinoma (HNSCC) develops in the mucosal lining of the upper aerodigestive tract, principally as a result of exposure to carcinogens present in tobacco products and alcohol, with oncogenic papillomaviruses also being recognized as etiological agents in a limited proportion of cases. As such, there is considerable scope for prevention of disease development and progression. However, despite multimodal approaches to treatment, tumor recurrence and metastatic disease are common problems, and clinical outcome is unsatisfactory. As our understanding of the genetics and biochemical aberrations in HNSCC has improved, so the development and use of molecularly targeted drugs to combat the disease have come to the fore. In this article, we review molecular mechanisms that alter signal transduction downstream of the epidermal growth factor receptor (EGFR) as well as those that perturb orderly cell cycle progression, such as p53 mutation, cyclin overexpression, and loss of cyclin-dependent kinase inhibitor function. We outline some of the tactics that have been employed to combat the altered biochemistry. These include blockade of the EGFR using humanized monoclonal antibodies such as cetuximab and small molecule tyrosine kinase inhibitors (TKIs) such as erlotinib/gefitinib and subsequent generations of TKIs, restoration of p53 function using MIRA compounds, and inhibition of cyclin-dependent kinase and aurora kinase activity using drugs such as palbociclib and alisertib. Knowledge of the underlying molecular mechanisms may be utilizable in order to predict disease behavior and tailor therapeutic interventions in a more personalized approach to improve clinical response. Use of liquid biopsy, omics platforms, and salivary diagnostics hold promise in this regard.

Targeting STAT3 and oxidative phosphorylation in oncogene-addicted tumors

Drug resistance invariably limits the response of oncogene-addicted cancer cells to targeted therapy. The upregulation of signal transducer and activator of transcription 3 (STAT3) has been implicated as a mechanism of drug resistance in a range of oncogene-addicted cancers. However, the development of inhibitors against STAT3 has been fraught with challenges such as poor delivery or lack of specificity. Clinical experience with small molecule STAT3 inhibitors has seen efficacy signals, but this success has been tempered by drug limiting toxicities from off-target adverse events. It has emerged in recent years that, contrary to the Warburg theory, certain tumor types undergo metabolic reprogramming towards oxidative phosphorylation (OXPHOS) to satisfy their energy production. In particular, certain drug-resistant oncogene-addicted tumors have been found to rely on OXPHOS as a mechanism of survival. Multiple cellular signaling pathways converge on STAT3, hence the localization of STAT3 to the mitochondria may provide the link between oncogene-induced signaling pathways and cancer cell metabolism. In this article, we review the role of STAT3 and OXPHOS as targets of novel therapeutic strategies aimed at restoring drug sensitivity in treatment-resistant oncogene-addicted tumor types. Apart from drugs which have been re-purposed as OXPHOS inhibitors for-anti-cancer therapy (e.g., metformin and phenformin), several novel compounds in the drug-development pipeline have demonstrated promising pre-clinical and clinical activity. However, the clinical development of OXPHOS inhibitors remains in its infancy. The further identification of compounds with acceptable toxicity profiles, alongside the discovery of robust companion biomarkers of OXPHOS inhibition, would represent tangible early steps in transforming the therapeutic landscape of cancer cell metabolism.

EGFR Inhibitors-related Panniculitis: A New Side Effect

Epidermal growth factor receptor (EGFR) inhibitors are widely used in the treatment of advanced malignancies, and their skin toxicity is frequent and well recognized in the literature. We report the case of a 69-year-old patient with a history of adenocarcinoma of the lung treated with several EGFR inhibitors and the development of skin lesions compatible with panniculitis. The reproducibility of the lesions with different inhibitors reinforces the causal relationship with the drug, representing the first report in the literature of this side effect.

Identifying nonsmall-cell lung tumours bearing the T790M EGFR TKI resistance mutation using PET imaging

Specific mutations significantly affect response to epidermal growth factor tyrosine kinase inhibitor (EGFR-TKI) treatment in lung cancer patients. Identifying patients with these mutations remains a major clinical challenge. EGFR T790M mutation, which conveys resistance to in the present study, [¹⁸ F]FEWZ was assessed in vitro to determine efficacy relative to the starting compound and in vivo to measure the biodistribution and specificity of binding to EGFR wild-type, L858R and T790M bearing tumours. [¹⁸ F]FEWZ is the first evidence of a radiolabeled third generation anilinopyrimidine-derived tyrosine kinase inhibitor targeting T790M mutation bearing tumours in vivo.

Combined plasma and tissue genotyping of EGFR T790M benefits NSCLC patients: a real-world clinical example

Acquired resistance to epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) is a prevalent clinical problem in the management of advanced non-small-cell lung cancer (NSCLC) with TKI-sensitizing mutations in the EGFR gene. Third-generation EGFR-TKIs have demonstrated potent activity against TKI resistance mediated by the EGFR T790M mutation, and standard rebiopsy and liquid biopsy are utilized to assess the T790M status of the NSCLC patients who experienced progressive disease (PD). Here, we conducted a retrospective study to assess 375 patients whose initial biopsy indicated a TKI-sensitizing mutation (either EGFR 19del or L858R) and who developed PD after treatment with first-generation TKIs, and assayed for T790M status. We adopted a combination approach in which tissue rebiopsy is preferred, utilizing liquid biopsies when tissue rebiopsy is not feasible. We analyzed the potential predictive clinical factors affecting T790M detection, evaluated the standard rebiopsy and liquid biopsy methods in T790M genotyping, and reported the clinical performance of osimertinib. Our results suggested that primary EGFR 19del, brain metastasis, and longer progression-free survival of initial EGFR-TKI treatment are associated with acquired T790M resistance. T790M-positive patients significantly benefited from osimertinib. In conclusion, the real-world clinical adoption of the combination approach with both tissue rebiopsy and liquid biopsy for T790M genotyping may provide significant benefits to patients who have developed PD after first-generation TKI treatments.

Synthesis and structure‑activity‑relationship of 3,4‑Diaryl‑1H‑pyrrolo[2,3‑b]pyridines as irreversible Inhibitors of mutant EGFR‑L858R/T790M

The epidermal growth factor receptor (EGFR) is a well‑validated drug target for the treatment of non‑small cell lung cancer. Here we present an optimization approach and preliminary structure‑activity relationship for 1H‑pyrrolo[2,3‑b]pyridines as covalent irreversible mutant EGFR inhibitors. We synthesized a focused library to investigate the effect of different aromatic substituents in the 4‑position of this scaffold, interacting with the gatekeeper. We determined the activity of the synthesized compounds mutant EGFR enzyme assays and determined the selectivity over the wild type.

Role of miR-520b in non-small cell lung cancer

The aim of the present study was to investigate the expression of microRNA (miR)-520b in non-small cell lung cancer (NSCLC) and its biological functions. Reverse transcription-quantitative polymerase chain reaction was used to detect the expression of miR-520b in 52 cases of NSCLC tissues, and its associations with tumor clinical staging and lymph node metastasis were analyzed. miR-520b mimics was transfected into A549 and Calu-3 cells. Cell proliferation, cell cycle, and cell invasion and migration abilities were assessed via cell counting kit-8 assay, flow cytometry and Transwell chamber assay, respectively. Western blot analysis was performed to detected protein expression levels, and dual luciferase reporter assay was used to detect the gene interaction. miR-520b expression was significantly downregulated in NSCLC. The expression of miR-520b in tumor tissues at N1 stage was lower than that at the N0 stage. miR-520b expression was negatively associated with clinical TNM staging. Furthermore, miR-520b mimic transfection inhibited the proliferation and invasion and metastasis abilities of A549 and Calu-3 cells. The expression of Rab22A was downregulated in the miR-520b mimics-transfected cells, whereas E-cadherin expression was increased, and vimentin expression was downregulated. Dual luciferase reporter assay demonstrated that miR-520b directly targeted the expression of Rab22A. Furthermore, Rab22A reversal downregulated the inhibitory effect of miR-520b. miR-520b expression was downregulated in NSCLC, which was negatively correlated with lymph node metastasis and TNM staging. miR-520b targeted on Rab22A to work as a tumor suppressor, inhibiting tumor proliferation and metastasis.

Molecular Diagnostics in Clinical Oncology

There are multiple applications of molecular tests in clinical oncology. Mutation analysis is now routinely utilized for the diagnosis of hereditary cancer syndromes. Healthy carriers of cancer-predisposing mutations benefit from tight medical surveillance and various preventive interventions. Cancers caused by germ-line mutations often require significant modification of the treatment strategy. Personalized selection of cancer drugs based on the presence of actionable mutations has become an integral part of cancer therapy. Molecular tests underlie the administration of EGFR, BRAF, ALK, ROS1, PARP inhibitors as well as the use of some other cytotoxic and targeted drugs. Tumors almost always shed their fragments (single cells or their clusters, DNA, RNA, proteins) into various body fluids. So-called liquid biopsy, i.e., the analysis of circulating DNA or some other tumor-derived molecules, holds a great promise for non-invasive monitoring of cancer disease, analysis of drug-sensitizing mutations and early cancer detection. Some tumor- or tissue-specific mutations and expression markers can be efficiently utilized for the diagnosis of cancers of unknown primary origin (CUPs). Systematic cataloging of tumor molecular portraits is likely to uncover a multitude of novel medically relevant DNA- and RNA-based markers.

Osimertinib as first-line therapy in advanced NSCLC: a profile of its use

Osimertinib (Tagrisso^®) is an oral, CNS-active, third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) that selectively inhibits EGFR TKI-activating mutations over wild-type EGFR in patients with advanced non-small cell lung cancer (NSCLC), including the T790M mutation that often underlies acquired resistance to earlier generation EGFR TKIs. Relative to standard of care first-generation EGFR TKIs (erlotinib or gefitinib) as first-line treatment of EGFR activating mutation-positive advanced NSCLC, osimertinib significantly prolongs median progression-free survival (PFS), with separation of the Kaplan-Meier PFS survival curves evident by the first assessment timepoint of 6 weeks. Osimertinib prolongs PFS relative to standard EGFR TKI therapy in all prespecified groups, irrespective of the EGFR mutation present at study entry and presence of CNS metastases at study entry. Overall survival data are not yet mature. Osimertinib has a generally manageable tolerability profile.

A consensus on the role of osimertinib in non-small cell lung cancer from the AME Lung Cancer Collaborative Group

The first- and second-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have brought substantial clinical benefit to patients with advanced non-small cell lung cancer (NSCLC) and sensitizing EGFR mutation. However, acquired resistance is inevitable since the vast majority of patients experience disease relapse within ~1-2 years. Osimertinib is a novel irreversible, covalent third-generation EGFR-TKI and potent inhibitor of EGFR T790M mutation, the most common mechanism of acquired resistance to first-generation EGFR-TKIs. Several trials have consistently demonstrated the superior clinical activity and safety of osimertinib in patients with advanced NSCLC and acquired EGFR T790M mutation after treatment with a first-generation EGFR-TKI. Recently, the efficacy of osimertinib in a first-line setting was demonstrated to be clearly superior to standard-first line treatment in patients with EGFR-mutant NSCLC regardless of T790M mutation status. Nevertheless, this advance, several unresolved issues of osimertinib should be emphasized including the molecular mechanisms of acquired resistance to osimertinib, the feasibility of testing EGFR T790M mutation from plasma circulating tumor DNA, its efficacy to patients with central nervous system (CNS) metastases or exon 20 mutations, its combination with other therapeutic strategies such as immune checkpoint inhibitors and its role in adjuvant therapy.

Anticancer effects of isofraxidin against A549 human lung cancer cells via the EGFR signaling pathway

Lung cancer is the leading cause of mortality due to tumor malignancy worldwide. In recent years, the treatment of lung cancer with chemotherapy has demonstrated notable resistance and insensitivity. Therefore, it is of great importance to investigate anti‑lung cancer drugs with high efficiency and low toxicity. In the present study, the effects of isofraxidin on lung cancer cells and the associated mechanisms were investigated. The results revealed that, in vivo and in vitro, isofraxidin exhibited marked inhibitory effects on the A549 lung cancer cell line. The results of Cell Counting kit‑8, Transwell migration and Matrigel invasion assays, and flow cytometry to determine apoptosis, revealed that isofraxidin significantly inhibited the proliferation, migration and invasion of A549 cells, and induced the cell apoptosis. Furthermore, western blot analysis demonstrated that isofraxidin treatment led to effects on the expression of apoptosis‑associated proteins, including members of the Bcl‑2 protein family, and invasion‑associated proteins, including matrix metallopeptidase (MMP)‑2 and MMP‑9, which may occur via inhibition of the expression of phosphorylated (p)‑epidermal growth factor receptor, p‑AKT and p‑extracellular signal‑regulated kinase. This regulation of protein expression may contribute to the inhibition of proliferation, migration and invasion of A549lung cancer cells by isofraxidin. In addition, despite the inhibitory effects on the A549 lung cancer cell line, the present study revealed that isofraxidin exhibited low toxicity towards BEAS‑2B normal lung epithelial cells within a certain dose range (0‑160 µM), indicating that isofraxidin may be employed for lung cancer treatment with hypotoxicity and fewer side effects. In conclusion, isofraxidin may be a novel candidate for anti‑lung cancer chemotherapy.

Advances in studies of tyrosine kinase inhibitors and their acquired resistance

Protein tyrosine kinase (PTK) is one of the major signaling enzymes in the process of cell signal transduction, which catalyzes the transfer of ATP-γ-phosphate to the tyrosine residues of the substrate protein, making it phosphorylation, regulating cell growth, differentiation, death and a series of physiological and biochemical processes. Abnormal expression of PTK usually leads to cell proliferation disorders, and is closely related to tumor invasion, metastasis and tumor angiogenesis. At present, a variety of PTKs have been used as targets in the screening of anti-tumor drugs. Tyrosine kinase inhibitors (TKIs) compete with ATP for the ATP binding site of PTK and reduce tyrosine kinase phosphorylation, thereby inhibiting cancer cell proliferation. TKI has made great progress in the treatment of cancer, but the attendant acquired acquired resistance is still inevitable, restricting the treatment of cancer. In this paper, we summarize the role of PTK in cancer, TKI treatment of tumor pathways and TKI acquired resistance mechanisms, which provide some reference for further research on TKI treatment of tumors.

Dihydroartemisinin suppresses STAT3 signaling and Mcl-1 and Survivin expression to potentiate ABT-263-induced apoptosis in Non-small Cell Lung Cancer cells harboring EGFR or RAS mutation

Non-small cell lung cancer (NSCLC) is the most common malignancy worldwide. A significant fraction of NSCLC carries activating mutations in epidermal growth factor receptor (EGFR) or RAS oncogene. Dihydroartemisinin (DHA) is a semisynthetic derivative of the herbal antimalarial drug artemisinin that has been recently reported to exhibit anti-cancer activity. To develop new therapeutic strategies for NSCLC, we investigated the interactions between DHA and ABT-263 in NSCLC cells harboring EGFR or RAS mutation. Our data indicated that DHA synergized with ABT-263 to trigger Bax-dependent apoptosis in NSCLC cells in culture. DHA treatment antagonized ABT-263-induced Mcl-1 upregulation and sensitized NSCLC cells to ABT-263-triggered apoptosis. Additionally, DHA treatment caused downregulation of Survivin and upregulation of Bim, which also contribute to cotreatment-induced cytotoxicity. Moreover, DHA effectively suppressed STAT3 phosphorylation, and STAT3 inactivation resulted in the downregulation of Mcl-1 and Survivin, functioning to enhance ABT-263-induced cytotoxicity. Finally, cotreatment of DHA and ABT-263 significantly inhibited xenograft growth in nude mice. Together, DHA effectively inhibits STAT3 activity and modulates expression of Mcl-1, Survivin and Bim, thereby synergizing with ABT-263 to trigger apoptosis in NSCLC cells harboring EGFR or RAS mutation. Our data provide a novel therapeutic strategy for EGFR or RAS mutant NSCLC treatment.

Oxymatrine inhibits non-small cell lung cancer via suppression of EGFR signaling pathway

Epidermal growth factor receptor (EGFR) plays a crucial role in human non–small cell lung cancer (NSCLC) tumorigenesis. In this study, oxymatrine was identified as an EGFR signaling pathway inhibitor in NSCLC. Oxymatrine inhibited anchorage‐dependent and independent growth of NSCLC cell lines but had no cytotoxicity in normal lung cells. We found that exposure to oxymatrine not only suppressed the activity of wild‐type EGFR but also inhibited the activation of exon 19 deletion and L858R/T790M mutated EGFR. Flow cytometry analysis suggested that oxymatrine‐induced cell cycle G0/G1 arrest was dependent on EGFR‐Akt signaling. Exogenous overexpression of Myr‐Akt rescued cyclin D1 expression in HCC827 cells. Moreover, oxymatrine prominently suppressed tumor growth in a xenograft mouse model. Thus, oxymatrine appears to be a novel therapeutic agent for NSCLC treatment.

Cost-Effectiveness of Osimertinib for EGFR Mutation-Positive Non-Small Cell Lung Cancer after Progression following First-Line EGFR TKI Therapy

OBJECTIVE

The aim of this study was to investigate the cost-effectiveness of osimertinib for the treatment of advanced NSCLC with an EGFR T790M mutation after the failure of first-line EGFR tyrosine kinase inhibitor (TKI) therapy.

METHODS

A mathematical model was established by combining a decision tree and the Markov approach to project the cost-effectiveness of osimertinib versus standard chemotherapy for the treatment of patients who harbor an EGFR T790M mutation and have disease progression after first-line EGFR TKI therapy with or without metastases to the central nervous system. The clinical and outcome data were derived from randomized clinical trials and published reports. The health outcome data included quality-adjusted life-years (QALY). The cost data were estimated from the perspectives of the payer in the United States and the health care system in the People's Republic of China. All costs and incremental cost-effectiveness ratios (ICERs) were presented in 2017 U.S. dollars. Sensitivity and scenario analyses with three different settings of T790M mutation testing were performed.

RESULTS

Compared with chemotherapy, molecular testing in plasma and tissue followed by osimertinib treatment yielded an additional 0.359 and 0.313 QALYs in the entire U.S. population and the population of those with central nervous system metastases and an EGFR T790M mutation. For these populations, the incremental costs were $83,515 and $74,924 per patient, respectively, and the ICERs were $232,895 and $239,274 per QALY, respectively. For the entire Chinese population and the Chinese population with central nervous system metastases, the ICERs were $48,081 and $53,244 per QALY, respectively. For those with a known T790M mutation, the ICERs of osimertinib over chemotherapy also exceeded the willingness-to-pay threshold. The most influential parameter was the price of osimertinib.

CONCLUSION

Osimertinib treatment for T790M mutation NSCLC is unlikely to be cost-effective from the perspectives of the United States and the People's Republic of China. If the price of osimertinib could be decreased, the economic outcome might become favorable.