Potent EGFR Tyrosine Kinase Inhibitor Research Articles

The Role of Proteomics and Phosphoproteomics in the Discovery of Therapeutic Targets and Biomarkers in Acquired EGFR-TKI-Resistant Non-Small Cell Lung Cancer

The discovery of potent EGFR-tyrosine kinase inhibitors (EGFR-TKIs) has revolutionized the treatment of EGFR-mutated lung cancer. Despite the fact that EGFR-TKIs have yielded several significant benefits for lung cancer patients, the emergence of resistance to EGFR-TKIs has been a substantial impediment to improving treatment outcomes. Understanding the molecular mechanisms underlying resistance is crucial for the development of new treatments and biomarkers for disease progression. Together with the advancement in proteome and phosphoproteome analysis, a diverse set of key signaling pathways have been successfully identified that provide insight for the discovery of possible therapeutically targeted proteins. In this review, we highlight the proteome and phosphoproteomic analyses of non-small cell lung cancer (NSCLC) as well as the proteome analysis of biofluid specimens that associate with acquired resistance in response to different generations of EGFR-TKI. Furthermore, we present an overview of the targeted proteins and potential drugs that have been tested in clinical studies and discuss the challenges of implementing this discovery in future NSCLC treatment.

Design, synthesis and biological evaluation of novel 3,4-dihydro-2H-[1,4]oxazino [2,3-f]quinazolin derivatives as EGFR-TKIs

Starting with our previously reported work, a novel series of 3,4-dihydro-2H-[1,4]oxazino[2,3-f]quinazolin-derivatives were designed, synthesized and evaluated as potent EGFR tyrosine kinase inhibitors. All of the compounds showed significant inhibitory activities against EGFRwt kinase (IC50 ≤ 937.7 nM). Among them, compound 7j demonstrated the most potent inhibitory activity toward EGFRwt tyrosine kinase with IC50 value of 25.69 nM and showed good antiproliferative activities against NCI-H1563 and H1975 cells. The median cytotoxic concentration (CC50) showed that most of the tested compounds displayed almost no cytotoxicity in vitro against 16HBE cells. In view of the reported compounds activity, the structure deserves further optimization as cancer treatment agents.

Histologic Transformation in EGFR-Mutant Lung Adenocarcinomas: Mechanisms and Therapeutic Implications.

Simple SummaryDespite being effective initially, almost all patients eventually develop resistance to EGFR-tyrosine kinase inhibitors (TKI). Changes in the histology of the tumor have been increasingly recognized as a critical mechanism of resistance to EGFR-directed therapies. This article summarizes histologic changes known to impart resistance to EGFR TKIs and discusses novel pathways to develop effective novel therapies.With the advent of potent EGFR tyrosine kinase inhibitors (TKIs), the treatment landscape of EGFR-mutant lung adenocarcinomas has changed drastically in recent years. However, the development of resistance to EGFR TKIs remains a critical barrier to improving survival in these patients. Histologic transformations to small cell lung carcinoma, large cell neuroendocrine carcinoma, squamous cell carcinoma, and the sarcomatoid phenotype have been increasingly recognized as important mechanisms of resistance. In this article, we summarize the known biological bases for such phenotypic switches in regard to EGFR TKIs and describe novel pathways that might be harnessed to develop effective novel therapies for patients with EGFR-mutant non-small cell lung cancers.

TAS6417/CLN-081 Is a Pan-Mutation-Selective EGFR Tyrosine Kinase Inhibitor with a Broad Spectrum of Preclinical Activity against Clinically Relevant EGFR Mutations.

Despite the worldwide approval of three generations of EGFR tyrosine kinase inhibitors (TKI) for advanced non-small cell lung cancers with EGFR mutations, no TKI with a broad spectrum of activity against all clinically relevant mutations is currently available. In this study, we sought to evaluate a covalent mutation-specific EGFR TKI, TAS6417 (also named CLN-081), with the broadest level of activity against EGFR mutations with a prevalence of ≥1%. Lung cancer and genetically engineered cell lines, as well as murine xenograft models were used to evaluate the efficacy of TAS6417 and other approved/in-development EGFR TKIs (erlotinib, afatinib, osimertinib, and poziotinib). We demonstrate that TAS6417 is a robust inhibitor against the most common EGFR mutations (exon 19 deletions and L858R) and the most potent against cells harboring EGFR-T790M (first/second-generation TKI resistance mutation). In addition, TAS6417 has activity in cells driven by less common EGFR-G719X, L861Q, and S768I mutations. For recalcitrant EGFR exon 20 insertion mutations, selectivity indexes (wild-type EGFR/mutant EGFR ratio of inhibition) favored TAS6417 in comparison with poziotinib and osimertinib, indicating a wider therapeutic window. Taken together, we demonstrate that TAS6417 is a potent EGFR TKI with a broad spectrum of activity and a wider therapeutic window than most approved/in-development generations of EGFR inhibitors. IMPLICATIONS: TAS6417/CLN-081 is a potent EGFR TKI with a wide therapeutic window and may be effective in lung cancer patients with clinically relevant EGFR mutations.

A Whole-Body Physiologically Based Pharmacokinetic Model of Gefitinib in Mice and Scale-Up to Humans.

Gefitinib (Iressa) is a selective and potent EGFR tyrosine kinase inhibitor. It received an accelerated FDA approval in 2003 for the treatment of patients with nonsmall cell lung cancer (NSCLC) and represents the first-line therapy for NSCLC with EGFR mutations. In the work presented herein, the disposition of gefitinib was investigated extensively in mouse in both plasma and 11 organs (liver, heart, lung, spleen, gut, brain, skin, fat, eye, kidney, and muscle) after a single IV dose of 20mg/kg. Gefitinib demonstrated extensive distribution in most tissues, except for the brain, and tissue to plasma partition coefficients (K pt) ranged from 0.71 (brain) to 40.5 (liver). A comprehensive whole-body physiologically based pharmacokinetic (PBPK) model of gefitinib in mice was developed, which adequately captured gefitinib concentration-time profiles in plasma and various tissues. Predicted plasma and tissue AUC values agreed well with the values calculated using the noncompartmental analysis (<25% difference). The PBPK model was further extrapolated to humans after taking into account the interspecies differences in physiological parameters. The simulated concentrations in human plasma were in line with the observed concentrations in healthy volunteers and patients with solid malignant tumors after both IV infusion and oral administration. Considering the extensive tissue distribution of gefitinib, plasma concentration may not be an ideal surrogate marker for gefitinib exposure at the target site or organ of toxicity (such as the skin). Since our whole-body PBPK model can predict gefitinib concentrations not only in plasma but also in various organs, our model may have clinical applications in efficacy and safety assessment of gefitinib.

Design, synthesis, and molecular docking studies of 2-(furan-2-yl)quinazolin-4-one derivatives as potential antiproliferative agents.

Fifteen new derivatives of quinazolin-4-one bearing the 2-furyl moiety at position 2 and a substituted phenyl moiety at position 3 were designed and synthesized to be evaluated as cytotoxic agents. Their chemical structures were confirmed by spectral and elemental analysis; cytotoxic activity evaluation was performed against HEPG2, HCT116, and MCF7 cancer cell lines using the sulforhodamine-B assay. All the tested compounds except 6a showed high potency against the HEPG2 cancer cell line (IC50 8-101 nM/mL); 11 compounds out of 15 proved to be potent against HCT116 cells (IC50 3-49 nM/mL), also 11 of the tested compounds showed high potency against MCF7 cells with IC50 values ranging from 7 to 63 nM/mL. The rest of the tested compounds showed IC50 values of more than 100 nM/mL. Compounds 3e and 4d are the most active compounds against HEPG2 cells; in addition, 3e is the most active compound against MCF7 cells. Also, compounds 4a, 3a, and 3b are the most active compounds against HCT116 cells. Compounds 3a, 3b, 3e, 4a, and 4d were also evaluated for their inhibitory activity against the EGFR tyrosine kinase (EGFR-TK) and showed a percentage inhibitory activity ranging from 53 to 84%. The most potent EGFR-TK inhibitors, 3a (84%), 3b (75%), and 3e (60%), were docked into the ATP binding site of the EGFR to explore their binding mode and possible interactions.

Population pharmacokinetics and pharmacogenomics of erlotinib: Effect of drug exposure on treatment outcomes in Japanese patients with non-small cell lung cancer.

2549 Background: Erlotinib is a potent EGFR tyrosine kinase inhibitor, currently used to treat non-small cell lung cancer (NSCLC). Erlotinib shows a significant pharmacokinetic (PK) variability and...

Biochemical Assay-Based Selectivity Profiling of Clinically Relevant Kinase Inhibitors on Mutant Forms of EGF Receptor

Gefitinib and erlotinib are potent EGFR tyrosine kinase inhibitors (potentially) useful for the treatment of non-small-cell lung cancer (NSCLC). Clinical responses, however, in NSCLC patients have been linked to the presence of certain activating mutations of EGFR. We used an ELISA-based biochemical assay to confirm the selective inhibitory efficacy of gefitinib and erlotinib on the activated mutant receptor. Our results are in line with the clinical observations providing evidence for the predictive power of the kinase assay. Four additional compounds were also investigated: CI-1033 and EKB-569 had dramatic inhibitory effects on all EGFR forms, whereas PD153035 and AG1478 were active on wild-type and activating mutant protein. In docking simulations with wild-type EGFR, our inhibitory data are in good agreement with the binding scores. These data confirm that anilinoquinazolines are good starting structures for the next generation of selective drugs against mutant EGFR, whereas CI-1033 and EKB-569 may represent advances for patients with both wild-type and anilinoquinazoline-resistant mutant tumors.

Syntheses of 4-(indole-3-yl)quinazolines – A new class of epidermal growth factor receptor tyrosine kinase inhibitors

The epidermal growth factor (EGF) family of membrane receptors has been identified as a key element in the complex signaling network that is utilized by various classes of cell–surface receptors. The synthesis and pharmacological results of 4-(indole-3-yl)quinazolines are described. The synthesized compounds are new high potent EGFR-tyrosine kinase inhibitors with excellent cytotoxic properties at different cell lines. Furthermore the 4-(indole-3-yl)quinazolines show some tendencies to inhibit the HER-2 TK, too. Moreover this substance class has remarkable strong fluorescence properties.

Synthesis and inhibitory activity of 4-alkynyl and 4-alkenylquinazolines: Identification of new scaffolds for potent EGFR tyrosine kinase inhibitors

The present study identified several 4-alkynyl and 4-alkenylquinazolines that serve as novel and potent EGFR tyrosine kinase inhibitors. The IC 50 values of these compounds are in the nanomolar range. In addition, the 4-(4-phenylbut-1-yn/en-yl)quinazolines provided scaffolds for potent enzyme inhibition. Chiral discrimination was observed to occur in one of the 4-alkynylquinazoline derivatives with the ( R)-isomer being more than 150 times as potent as the ( S)-isomer.

Phase II trial of erlotinib with temozolomide and concurrent radiation therapy in patients with newly-diagnosed glioblastoma multiforme

1567 Background: Approximately 40 - 50% of GBM tumors overexpress EGFR, which activates tyrosine kinase to promote GBM cell infiltration in vitro. Radioresistance of some GBMs has been correlated with EGFR overexpression. Erlotinib is a specific and potent EGFR tyrosine kinase inhibitor (TKI) with activity against refractory GBM. Furthermore, the occurrence of erlotinib-induced rash of ≥ grade 2 has been correlated with improved survival in non-small cell lung cancer. A phase 2 trial of erlotinib with concurrent RT-temozolomide (RT-tmz) was therefore initiated with pharmacodynamic dosing of erlotinib. Methods: Eligible patients (pts) have newly diagnosed GBM; age ≥ 18; KPS ≥ 60; no cytochrome P-450 enzyme-inducing anticonvulsants; no prior temozolomide (tmz), TKI or cranial RT. Pts receive RT 60 Gy in 30 fractions with concurrent tmz (75 mg/m2/day × 7 days/week). Four weeks after RT-tmz pts receive tmz 150 mg/m2/day × 5 days, every 28 days for 12 cycles. Pts receive erlotinib daily from day 1 of RT until disease progression. Erlotinib dosing starts at 50mg/day with escalation every 2 weeks by 50mg/day until the occurrence of grade 2 rash or 150 mg/day. All tumors have FISH assay for EGFR amplification. Results: To date 11 patients have enrolled with a median follow up of 11 weeks (range 9–22); 2 did not start therapy and 4 remain on study. The median age is 47 (18–65); KPS 90 (70–100). Two pts had gross total resection. Seven pts are EGFR negative. Maximum dose of erlotinib reached before grade (G) 2 rash: 50 mg/d (1 pt), 100 mg/d (1 pt), and 150 mg/day (2pts). Three pts reached 150 with G0 or 1 rash and 2 pts are still on escalating doses of erlotinib. Of 9 pts evaluable for response, best response has been stable disease (3 pts) of 10.5, 7 and 3.5+ months duration; progression (3), and too early (3). No pt has had G4 toxicity. G3 toxicity has included neutropenia (1 pt) and lymphopenia (2). Additional events unrelated to therapy have included wound infection, spontaneous pneumothorax, and rectus sheath hematoma. Conclusions: The combination of erlotinib with RT-tmz is feasible and overall has been well tolerated. Dose escalation to a pharmacodynamic endpoint is feasible in GBM. Accrual continues. Author Disclosure Employment or Leadership Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Genentech Genentech

Salicylanilides as Inhibitors of the Protein Tyrosine Kinase Epidermal Growth Factor Receptor.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Salicylanilides as inhibitors of the protein tyrosine kinase epidermal growth factor receptor

A pharmacophore model for ATP-competitive inhibitors interacting with the active site of the EGFR protein tyrosine kinase and a putative binding mode of 4-anilinoquinazoline suggest that a salicylic acid function could serve as the pharmacophore replacement of a pyrimidine ring. Superpositions by CAMM of salicylanilides with the potent EGFR tyrosine kinase inhibitor 4-[(3′-chlorophenyl)amino]-6,7-dimethoxyquinazoline showed that salicylanilides should act as tyrosine kinase inhibitors. A series of salicylanilides was synthesized and their inhibitory activity against tyrosine kinases determined. Some of them indeed proved to be potent and selective EGFR tyrosine kinase inhibitors. The most potent ones being 28, 16, 20, 6, and 15, with IC 50 in the 23–71 nM range.

Use of a pharmacophore model for the design of EGFR tyrosine kinase inhibitors: isoflavones and 3-phenyl-4(1H)-quinolones.

Using a pharmacophore model for ATP-competitive inhibitors interacting with the active site of the EGFR protein tyrosine kinase together with published X-ray crystal data of quercetin (2) in complex with the Hck tyrosine kinase and of deschloroflavopiridol (3b) in complex with CDK2, a putative binding mode of the isoflavone genistein (1) was proposed. Then, based on literature data suggesting that a salicylic acid function, which is represented by the 5-hydroxy-4-keto motif in 1, could serve as a pharmacophore replacement of a pyrimidine ring, superposition of 1 onto the potent EGFR tyrosine kinase inhibitor 4-(3'-chlorophenylamino)-6, 7-dimethoxyquinazoline (4) led to 3'-chloro-5,7-dihydroxyisoflavone (6) as a target structure which in fact was 10 times more potent than 1. The putative binding mode of 6 suggests a sulfur-aromatic interaction of the m-chlorophenyl moiety with Cys 773 in the "sugar pocket" of the EGFR kinase model. Replacement of the oxygen in the chromenone ring of 6 by a nitrogen atom further improved the inhibitory activity against the EGFR kinase. With IC50 values of 38 and 8 nM, respectively, the quinolones 11 and 12 were the most potent compounds of the series. N-Alkylation of 11 did not further improve enzyme inhibitory activity but led to derivatives with cellular activity in the lower micromolar range.

Synthesis and biological activity of 5-[(2,5-dihydroxybenzyl)amino]salicylic acid analogs as inhibitors of EGF receptor-associated protein tyrosine kinase

The synthesis and biological activity of a series of 5-[(2,5-dihydroxybenzyl)amino]salicylic acid derivatives ( 3–6) as analogs of the active partial structure ( 2) of the potent EGF-R tyrosine kinase inhibitor lavendustin A ( 1) are described. Analogs with an electron-withdrawing group in place of the carboxyl group of 2 showed activity. The N-hexylsalicylamide analog 6b (IC 50=0.9 μM) was about four times more potent than 2.