Design, synthesis and biological evaluation of potent epidermal growth factor receptor tyrosine kinase (EGFR-TK) inhibitors against resistance mutation for lung cancer treatment.

In this study, we identified a newly synthesized compound 7o with potent inhibition on EGFR primary mutants (L858R, Del19) and drug-resistant mutant T790M with nanomolar IC50 values. 7o showed strong antiproliferative effects against EGFR mutant-driven non-small cell lung cancer (NSCLC) cells such as H1975, PC-9 and HCC827, over cells expressing EGFRWT. Molecular docking was performed to investigate the possible binding modes of 7o inside the binding site of EGFRL858R/T790M and EGFRWT. Analysis of cell cycle evidenced that 7o induced cell cycle arrest in G1 phases in the EGFR mutant cells, H1975 and PC-9, which resulted in decreased S-phase populations. Moreover, compound 7o induced cancer cell apoptosis in in vitro assays. In addition, 7o inhibited cellular phosphorylation of EGFR. In vivo, oral administration of 7o caused rapid tumor regression in H1975 xenograft model. Therefore, 7o might deserve further optimization as cancer treatment agent for EGFR mutant-driven NSCLC.

The new N2, N4-diphenylpyridine-2,4-diamine deuterated derivatives as EGFR inhibitors to overcome C797S-mediated resistance.

A series of new deuterated and non-deuterated N2, N4-diphenylpyridine - 2,4-diamine derivatives were synthesized and evaluated as EGFR C797S-mediated resistance inhibitors. Most of these compounds exhibited potent antiproliferative activity against Baf3-EGFR L858R/T790M/C797S and Baf3-EGFR Del19/T790M/C797S cancel cell lines, with IC50 values in the nanomolar concentration range. Among them, compound 14l represented the most active compound with IC50 values of 8-11 nM. Interestingly, metabolic stability assay with rat liver microsomes indicated that the half-life of the deuterated derivative 14o was significantly increased compared to that of 14l. In xenograft mice models, 14o inhibited tumor growth with excellent inhibitory rate of 75.1 % at the dosage of 40 mg/kg, comparing 73.2 % of the TGI with its non-deuterated compound 14l, at a dosage of 80 mg/kg. Mechanism studies revealed that 14o was a potent EGFR L858R/T790M/C797S and EGFR Del19/T790M/C797S kinase inhibitor, which could downregulate the protein phosphorylation of EGFR and m-TOR signaling pathways, arrest cell cycle at G2/M phase by affecting the expression of CDC25C, and promote cell apoptosis by regulating the expression of cleaved caspase-3. In summary, 14o could serve as a promising deuterated compound for the development of highly efficient anticancer agents.

Design, synthesis and biological evaluation of novel tumor hypoxia-activated EGFR tyrosine kinase inhibitors.

Hypoxia is widespread in solid tumors, such as NSCLC, and has become a very attractive target. On the basis of AZD9291 scaffold, novel hypoxia-targeted EGFR inhibitors without the acrylamide warhead but containing hypoxic reductive activation groups were described. Among them, compound JT21 exhibited impressive inhibitory activity (IC50 = 23 nM) against EGFRL858R/T790M and displayed about 21-fold inhibitory activity decrease against EGFRwt. Under hypoxia, JT21 exhibited more significant proliferation inhibitory activities against H1975 cells (IC50 = 7.39 ± 2.20 nM) and HCC827 cells (IC50 = 5.88 ± 0.85 nM) than that of AZD9291, which was about 5 times more effective than normoxia activities. Meanwhile, the weak inhibition effects on A549 and BEAS-2B cells suggested JT21 might be a selective inhibitor for EGFR mutations with low toxicity. Furthermore, JT21 could induce apoptosis of H1975 cells under hypoxia and showed good bio-reductive property.

Toward discovery of mutant EGFR inhibitors; Design, synthesis and in vitro biological evaluation of potent 4-arylamino-6-ureido and thioureido-quinazoline derivatives.

A new series of 4-anilinoquinazolines with C-6 ureido and thioureido side chains and various substituents at the C-4 anilino moiety was designed, synthesized and evaluated as wild type (WT) and mutant EGFR inhibitors. Most of the compounds inhibited EGFR kinase wild type (EGFR WT) with IC50 values in the low nanomolar range (<0.495-9.05nM) and displayed more potent cytotoxic effect in BaF/3 expressing EGFR WT than reference compound gefitinib. The anti-proliferative effect of all synthesized compounds against gefitinib insensitive double mutant cell lines Ba/F3 expressing Del19/T790M and Ba/F3 expressing L858R/T790M were assayed. Compounds 4d, 6f, 7e showed significant inhibition (IC50=1.76-2.38µM) in these mutant lines and significant Her2 enzyme inhibition (IC50=19.2-40.6nM) compared to lapatinib (60.1nM). The Binding mode of compounds 6d, 6f, 7a, 7b and 8b were demonstrated. Furthermore, growth inhibition against gefitinib insensitive cell lines PC9-GR4 (Del19/T790M) were tested, compounds 6f and 7e showed about eight and three folds respectively greater potency than gefitinib. Our structure-activity relationships (SAR) studies suggested that presence of ethyl piperidino urea/thiourea at 6-position and bulky group of (3-chloro-4-(3-fluorobenzyloxy)phenyl)amino at 4-position of quinazoline may serve as promising scaffold for developing inhibitors against wild type and mutant EGFR.

Comparing overall survival between first generation EGFR-TKIs and chemotherapy in lung cancer patients with Del19/L858R.

OBJECTIVE: Combined overall survival (OS) analysis of Lux-Lung 3 and Lux-Lung 6 demonstrated that patients with epidermal growth factor receptor (EGFR) exon 19 deletions (Del19) would benefit from first-line second generation EGFR tyrosine kinase inhibitors (TKIs) afatinib but not for those with L858R. This study was to investigate the survival difference between first-line first generation EGFR-TKIs and chemotherapy in patients with either Del19 or L858R, and to directly compare OS in these two mutation groups. METHODS: Eligibles were all prospective and retrospective studies comparing EGFR-TKIs with conventional chemotherapy or receiving single agent EGFR-TKIs and demonstrating survival analysis based on mutation types. The primary outcome was OS measured as pooled hazard ratios (HRs). All measures were pooled using randomeffects models and 95% confidential interval (95% CI) was calculated. RESULTS: A total of 14 studies incorporating 1,706 patients with either Del19 or L858R were included. Enrolling patients with Del19 or L858R in randomized controlled trials (RCTs), first-line first generation EGFR-TKIs were associated with no OS benefit, compared with chemotherapy (pooled HRTKI/Chemo for Del19: 0.82, 95% CI: 0.64-1.06, P = 0.14; pooled HRTKI/Chemo for L858R: 1.15, 95% CI: 0.85-1.56, P = 0.38). Direct comparison of Del19 with L858R receiving with first-line first generation EGFR-TKIs demonstrated no significant survival difference (pooled HR19/21: 0.88, 95% CI: 0.67-1.16, P = 0.37). CONCLUSIONS: Among patients with advanced non-small cell lung cancer (NSCLC) harboring Del19 and L858R, first-line first generation EGFR-TKIs demonstrated no survival benefit comparing with chemotherapy. Direct comparison between Del19 and L858R revealed no significant survival difference after first-line first generation EGFR-TKIs.

Common EGFR-mutated subgroups (Del19/L858R) in advanced non-small-cell lung cancer: chasing better outcomes with tyrosine kinase inhibitors.

Ten years ago, somatic mutations in EGFR were identified in patients with non-small-cell lung cancer. Demonstration of the antitumor efficacy of EGF receptor-directed tyrosine kinase inhibitors resulted in their approval for the treatment of advanced non-small-cell lung cancer. Insights into the role of EGFR-sensitizing mutations and acquired and de novo T790M resistance mutations followed, and differences in progression-free survival for patients with EGFR Del19- and L858R-mutated tumors treated with reversible first-generation EGF receptor tyrosine kinase inhibitors were reported. Recently, overall survival benefit in patients with Del19- but not L858R-mutated tumors has been demonstrated after treatment with afatinib, an irreversible ErbB family blocker. Although the biology underlying this difference in survival is currently unclear, this review examines several hypotheses.

Management of the adverse events of afatinib: a consensus of the recommendations of the Spanish expert panel.

Afatinib is an irreversible ErbB family blocker tyrosine kinase inhibitor (TKI), which has recently been approved for the treatment of patients with EGFR M+ non-small cell lung cancer. As observed with reversible EGFR TKIs, it can induce class-effect adverse events. Appropriate management of afatinib-related adverse events improves quality of life and clinical outcomes in these patients. Here we provide practical recommendations for the prophylaxis and treatment of the most common of these (e.g., diarrhea, rash, mucositis and others).

Machine learning-based algorithm demonstrates differences in del19 and L858R EGFR subgroups in non-small cell lung cancer: a single center experience.

BACKGROUND: Exon del19 and L858R mutations account for 90% of EGFR mutant non-small cell lung cancer (NSCLC). LUX lung 3 and 6 initially reported a survival difference between these two. However, other studies did not demonstrate the same. By using machine learning (ML), it is possible to discover novel patterns for cancer susceptibility, recurrence, prognostication, and therapy. We evaluate the effect of these two molecular subtypes on overall survival/progression-free survival (OS/PFS). METHODS: 413 patients with stage IV EGFR mutant NSCLC were analyzed for clinicopathologic features, treatment details, and survival outcome. PFS prediction models were built using ensemble decision trees, and random forest. Ensemble decision trees were built and validation was performed using survival analysis. Clustering regression techniques were then applied to train and test the prediction of the 1st PFS of patients. RESULTS: The median age of the cohort was 59 years comprising 53% males and 47% females. 275 (66.5%) patients showed a del19 mutation type and 138 (33.5%) harbored L858R. After clustering, the most important variables were age (P<0.05), ECOG performance status (PS) (P<0.04), PDL1 (P<0.09), smoking status (P<0.01) and to a lesser extent, number of extrathoracic metastasis (ETM) sites (median 1.2, P<0.06), brain metastasis (P<0.06) and gender (P<0.08). The prediction for 1st PFS for del19 showed mean absolute error of 2.6 months and 4.72 months for L858R. The accuracy was 79.8% with 82% sensitivity, 79% specificity and AUC: 0.72. The precision was 92% with a Mathews correlation coefficient of 0.59. CONCLUSION: This study used machine learning modeling with fair accuracy to demonstrate that ECOG PS, age at diagnosis, and smoking status are the three main predictive factors of PFS in these patients.

Real-world data with afatinib in Spanish patients with treatment-naïve non-small-cell lung cancer harboring exon 19 deletions in epidermal growth factor receptor (Del19 EGFR): Clinical experience of the Galician Lung Cancer Group.

BACKGROUND: In clinical studies, first-line afatinib demonstrated efficacy in Del19-EGFR NSCLC. MATERIALS AND METHODS: This prospective, non-interventional study assessed efficacy and safety of first-line afatinib in patients with advanced/metastatic NSCLC with Del19-EGFR from Galicia (Spain), with a preplanned analysis by age (<70 vs ≥70 years). RESULTS: Median age of 46 patients enrolled was 69.5 years (range 37-87). The objective response rate (ORR) was 78.2%, with median progression-free survival (PFS) of 20.5 months (95% CI 12.7, 28.3) and median overall survival (OS) of 37.5 months (95% CI 19.2-55.8). Outcomes by age (<70 vs ≥70 years) were ORR of 82.6% vs 73.9%, median PFS of 20.2 months (95% CI 14.8-25.6) vs 24.1 (9.8-38.3), and median OS of 45.1 months (95% CI, 17.0-73.1) vs 33.9 (28.7-39.1), respectively. Median treatment duration was 17.2 months (range 0.4-64.1) with 11 patients still on treatment; 14 patients received osimertinib at discontinuation due to T790M. Grade 3 adverse events included mucositis (n = 7, 15.2%), skin toxicity (n = 9, 19.6%), and diarrhea (n = 6, 13.0%) that were manageable with dose reductions. The afatinib dose was reduced in 31 patients (67.4%) and treatment was discontinued in 8 patients (17.4%) due to adverse events. By age (<70 vs ≥70 years), afatinib was dose-reduced in 13 (56.5%) vs 18 patients (78.3%) and discontinued in 3 (13.0%) vs 5 patients (21.7%), respectively. CONCLUSIONS: PFS in our patients was longer than reported in clinical studies with similar response rates and toxicity, even in older patients, reflecting a good risk-benefit from afatinib in patients with Del19-EGFR NSCLC. MICROABSTRACT: This real-world study of first-line afatinib in Caucasian patients with Del19 EGFR NSCLC reported durable efficacy and showed that older patients (> 70 years) benefitted from afatinib as much as younger patients. The safety profile of afatinib was as expected, albeit more dose reductions in older patients. Afatinib may be an option for patients with Del19 EGFR NSCLC, even in those who are older.

Extensive-Stage Small Cell Carcinoma Transformation From EGFR Del19-Mutant Lung Adenocarcinoma on Gefitinib at the Twelfth-Year Follow-Up Case Report.

INTRODUCTION: The acquired resistance mechanisms in patients with epidermal growth factor receptor (EGFR)-mutant lung cancer, particularly adenocarcinoma (ADC), following treatment with an EGFR tyrosine kinase inhibitor (TKI) have received extensive investigations. The phenotypic transformation to small cell carcinoma (SCCT) has been estimated to occur in approximately 3 to 10% of patients treated with an EGFR-TKI. The prognosis after SCCT is extremely poor. CASE STUDY: We report about SCCT that occurred 45 months after the initial diagnosis of ADC in an East Asian never-smoker woman with advanced-stage EGFR Del-19-mutant lung ADC treated with combined chemoradiotherapy before the era of insurance coverage for EGFR-TKIs in this country and subsequently gefitinib; deletion at codon 746-750 in exon 19 of the EGFR gene was ascertained in the original formalin-fixed paraffin-embedded lung biopsy tissue. Spinal cord compression at thoracic-12 level from SCCT was successfully relieved with neurosurgical treatment, chemotherapy with etoposide and cisplatin, and radiotherapy, while gefitinib treatment was maintained. Eleven months later, SCCT relapsed in the lung parenchyma, which was resected and was found to be sensitive to second-line weekly topotecan. Prophylactic cranial irradiation was subsequently administered. SCCT was confirmed by MALDI-TOF MS analysis of formalin-fixed paraffin-embedded tissues demonstrating the same exon 19 deletion. At the 12th-year follow-up, the patient remains relapse free with very good performance status. The novelty of this case is the successful interdisciplinary team effort to correct the spinal cord compression by maintaining the patient in an ambulatory state, non-stop use of gefitinib justified by the presence of activating EGFR mutation in SCCT tumor cells, and aggressive dose-intensive chemotherapy and radiotherapy for the SCCT that leads to an unprecedented prolonged remission and survival. This case also supports the observation that SCCT is chemotherapy sensitive, and thus, re-biopsy or complete tumor excision is recommended to understand the mutation profiles of the current tumor. Aggressive prudent administration of systemic chemotherapy obtaining optimal dose intensity leads to the successful management of the patient.

An Evolving Algorithm to Select and Sequence Therapies in EGFR Mutation-positive NSCLC: A Strategic Approach.

The optimal treatment sequence for patients with metastatic epidermal growth factor receptor (EGFR) mutation-positive (EGFR-M+) non-small-cell lung cancer (NSCLC) continues to evolve, related largely to an increasing number of breakthroughs and studies in the field. The efficacy of tyrosine kinase inhibitors in the treatment of these patients is well established; however, the treatment decision-making process is becoming more complex as our knowledge of EGFR mutations and resistance pathways grows and more treatment options become available. Thus, treating physicians must consider an increasing number of factors. We present a stepwise approach to personalizing the treatment of patients with EGFR-M+ NSCLC, emphasizing some of the real world challenges faced by treating physicians. We reviewed the decision criteria for selecting the best first-line therapy, highlighted the importance of repeat biopsy on disease progression to determine the most appropriate next-line therapy, and discussed the options for third-line therapy and beyond. We also present an algorithm designed to optimize the sequencing strategies for prolonging survival and maintaining quality of life in our patients with EGFR-M+ NSCLC.

The predictive role of pretreatment epidermal growth factor receptor T790M mutation on the progression-free survival of tyrosine-kinase inhibitor-treated non-small cell lung cancer patients: a meta-analysis.

PURPOSE: Subclones bearing the epidermal growth factor receptor (EGFR) T790M mutation concomitant with deletional mutation in exon 19 (Del19) or a point mutation in exon 21 (L858R) have been reported in non-small cell lung cancer patients before any EGFR tyrosine-kinase inhibitor (TKI) treatment. The effect of pretreatment T790M mutation on the survival of patients with both mutations treated with EGFR TKI is still being debated. METHODS: A meta-analysis was undertaken to pool eligible trials to better elucidate whether pretreatment T790M mutation predicts a poorer outcome of EGFR TKI treatment. Hazard ratios and their 95% confidence intervals for progression-free survival (PFS) were extracted and used under the random-effects model. RESULTS: A total of 246 patients with activating EGFR mutation such as Del19 or L858R participated in four selected trials from 350 articles. The overall incidence of patients with pretreatment T790M mutation was 43.10% (106/246), ranging from 34.88% to 80.00% in the individual trials. The combined hazard ratio for PFS in all four eligible studies was 2.602 (95% confidence interval 1.011-6.695; P=0.047), indicating a shorter PFS in patients who had the T790M mutation before receiving EGFR TKI treatment. Heterogeneity testing indicated significant heterogeneity but the absence of publication bias. CONCLUSION: The meta-analysis reported here found that pretreatment T790M mutation had a negative impact on the PFS of non-small cell lung cancer patients with a Del19 or L858R EGFR mutation who received EGFR TKI treatment.

Prolactin receptor antagonism uncouples lipids from atherosclerosis susceptibility.

The pituitary-derived hormone prolactin has been suggested to stimulate the development of atherosclerosis and cardiovascular disease through its effects on metabolism and inflammation. In this study, we aimed to challenge the hypothesis that inhibition of prolactin function may beneficially affect atherosclerosis burden. Hereto, atherosclerosis-susceptible LDL receptor (Ldlr) knockout mice were transplanted with bone marrow from transgenic mice expressing the pure prolactin receptor antagonist Del1-9-G129R-hPRL or their non-transgenic littermates as control. Recipient mice expressing Del1-9-G129R-hPRL exhibited a decrease in plasma cholesterol levels (-29%; P<0.05) upon feeding a Western-type diet (WTD), which could be attributed to a marked decrease (-47%; P<0.01) in the amount of cholesterol esters associated with pro-atherogenic lipoproteins VLDL/LDL. By contrast, Del1-9-G129R-hPRL-expressing mice did not display any change in the susceptibility for atherosclerosis after 12 weeks of WTD feeding. Both the absolute atherosclerotic lesion size (223 ± 33 × 10(3) µm(2) for Del1-9-G129R-hPRL vs 259 ± 32 × 10(3) µm(2) for controls) and the lesional macrophage and collagen contents were not different between the two groups of bone marrow recipients. Importantly, Del1-9-G129R-hPRL exposure increased levels of circulating neutrophils (+91%; P<0.05), lymphocytes (+55%; P<0.05), and monocytes (+43%; P<0.05), resulting in a 49% higher (P<0.01) total blood leukocyte count. In conclusion, we have shown that prolactin receptor signaling inhibition uncouples the plasma atherogenic index from atherosclerosis susceptibility in Ldlr knockout mice. Despite an associated decrease in VLDL/LDL cholesterol levels, application of the prolactin receptor antagonist Del1-9-G129R-hPRL does not alter the susceptibility for initial development of atherosclerotic lesions probably due to the parallel increase in circulating leukocyte concentrations.

Estudio TAMARA II. Tabaquismo en médicos de la República Argentina II / The tamara ii trial. smoking among physicians in argentina

background: Smoking is the leading cause of preventable morbidity and death. It is important to know the characteristics of smoking habits among physicians and their attitude toward patients who smoke. Objective: The aim of this study is to investigate the prevalence of smoking among physicians in Argentina, the factors associated with tobacco consumption and their attitude toward their patients who smoke. Methods: An observational cross- sectional study was performed between June and December 2013 in Argentine physicians of dif-ferent specialties. Using a structured survey, the following variables were analyzed: associated cardiovascular risk factors, charac-teristics of tobacco consumption, smoking cessation training and the attitude toward the patient who smokes. results: 3,033 physicians were surveyed, ; 57% were men, and mean age was 41.3±12 years; 19.7% were current smokers and 21.7% were former smokers. The probability of being a smoker was higher among surgeons (OR 1.29) or physicians working at the emergency room (OR 1.41). Undergraduate and postgraduate tobacco cessation training was achieved by 36.6% and 40.8% of physicians, respectively. Young physicians, clinical specialties or private practice were associated with higher level of training. Tobacco cessation counseling was more frequent in physicians with higher level of training than physicians who smoked or surgeons. Former smokers presented higher prevalence of risk factors and cardiovascular events. Family history of smoking habit was more common in former smokers and current smokers. Conclusions: The prevalence of smoking among Argentine physicians is high. Different factors are involved in the probability of smoking, tobacco cessation training or the possibility of medical counseling. Higher level of training in smoking cessation must be provided.