Bioanalysis of erlotinib, its O-demethylated metabolites OSI-413 and OSI-420, and other metabolites by liquid chromatography-tandem mass spectrometry with additional ion mobility identification.

Erlotinib is a first-generation epithelial growth factor receptor inhibitor used in the treatment of non-small cellular lung cancers. Our previously published method on a Thermo TSQ Quantum Ultra triple quadrupole mass spectrometer for the quantitation of erlotinib, OSI-420, and OSI-413 and some other kinase inhibitors was transferred to a more sensitive Sciex QTRAP5500 system. Both methods showed comparable performance in the previous range (5-5000 and 1-1000 ng/mL for erlotinib and OSI-420) with comparable accuracies and precisions (98.9-106.2 vs 98.7.0-104.0, and 3.7-13.4 vs 4.6-13.2), and a high level of agreement between the methods (R2 = 0.9984 and 0.9951) for the quality control samples. The new system however was also capable of quantifying lower concentrations of both erlotinib and OSI-420 (0.5 and 0.1 ng/mL) with sufficient accuracy and precision. Along with the increased sensitivity we included the semi-quantitative determination of additional erlotinib metabolites M2, M3, M5, M6, M7, M8, M9, M10, M11, M12, M16 (hydroxy-erlotinib), M17, M18, M19, M20, M21 in a 0.1-1000 ng/mL range to the method. With a simple crash, dilute, and shoot sample preparation with acetonitrile and a 4.5 min analytical run time the method outperformed most other published methods in speed and simplicity and was suitable for TDM. Further, enhancement of the understanding of the pharmacokinetics of erlotinib and its metabolites was demonstrated.

Arylidenes of Quinolin-2-one scaffold as Erlotinib analogues with activities against leukemia through inhibition of EGFR TK/ STAT-3 pathways.

A new series of 6-substiuted-4-(2-(4-substituted-benzylidene)hydrazinyl)quinolin-2(1H)-one derivatives have been designed and synthesized. The structure of the synthesized compounds was proved by 1H NMR, 13C NMR, 2D NMR, mass and elemental analyses. The target compounds were evaluated for their in vitro cytotoxic activity against 60 cancer cell lines according to NCI protocol. Consequently, the most active compounds were further examined against the most sensitive leukemia RPMI-8226 and on healthy cell lines. 6-Chloro-derivative was the most active one; with IC50 = 15.72 ± 1.21 and 46.05 ± 2.36 µM against RPMI-8226 and normal cell lines, respectively. Also, it showed a remarkable inhibitory activity compared to gefitinib on the EGFR TK mutant, wild and on H-RAS in addition to STAT-3 with IC50 = 695.49 ± 21.8, 263.15 ± 15.13, 10.61 ± 0.27 and 1.753 ± 0.81 nM, respectively. Cell cycle analysis of RPMI-8226 cells treated with the 6-chloro-derivative showed cell cycle arrest at G2/M phase (supported by Caspases-3,8, BAX and Bcl-2 studies) with a significant pro-apoptotic activity as indicated by annexin V-FITC staining. Moreover, the docking studies ROCS analysis and Tanimoto scores supported the results. The study illustrated the effect of several factors on compounds activity.

An Erlotinib gold(I) conjugate for combating triple-negative breast cancer.

An Erlotinib triphenylphosphane gold(I) conjugate has been prepared from AuCl(PPh3) and its crystal structure has been established by X-ray diffraction, showing a metallo-helicate formation. IC50 values of the new gold conjugate were calculated towards a panel of human tumor cell lines representative of breast (MCF-7, MDA-MB-231) and colon (HT-29) cancer cells. Overall, the gold conjugate exhibited higher cytotoxic activity than that of Erlotinib against the cancer cells studied. Particularly, the antiproliferative effect of the conjugate demonstrated to be 68-fold higher than Erlotinib in highly metastatic and triple negative MDA-MB-231 cell line. The gold conjugate caused DNA damage, reactive oxygen species (ROS) increase and induced apoptosis. Flow cytometry analysis showed that the conjugate induces significant arrest in S and G2/M phases primarily, whereas Erlotinib, as an inhibitor of epidermal growth factor receptor (EGFR), blocks G1/S transition and increases G1 cell population.

Development of a Fluorinated Analogue of Erlotinib for PET Imaging of EGFR Mutation-Positive NSCLC.

PURPOSE: Positron emission tomography (PET) using [11C]erlotinib identifies non-small cell lung carcinoma (NSCLC) tumors with activating mutations in the epidermal growth factor receptor (EGFRm). The short half-life of C-11, however, limits its clinical utility to centers with a nearby cyclotron. We therefore developed a F-18-labeled analogue of erlotinib for imaging EGFRm NSCLC. PROCEDURES: 6-O-Fluoroethylerlotinib (6-O-FEE) was synthesized and its anti-proliferative activity was tested using human NSCLC cell lines. The F-18-labeled compound, 6-O-[18F]FEE, was obtained in a two-step synthesis, and PET acquisitions were carried out following its injection to NSCLC tumor-bearing mice. RESULTS: In vitro, 6-O-FEE had maintained the selectivity and potency of erlotinib to EGFRm NSCLC. In vivo, 6-O-[18F]FEE accumulation in EGFRm tumors at 60 min after injection was 2- and 3.3-fold higher than in erlotinib-resistant or erlotinib-insensitive tumors, respectively. CONCLUSIONS: 6-O-[18F]FEE holds promise for imaging EGFRm NSCLC, warranting further investigation to fully explore its potential for stratifying NSCLC patients.

Synthesis and biological assay of erlotinib analogues and BSA-conjugated erlotinib analogue.

A series of erlotinib analogues that have structural modification at 6,7-alkoxyl positions is efficiently synthesized. The in vitro anti-tumor activity of synthesized compounds is studied in two non-small cell lung cancer (NSCLC) cell lines (A549 and H1975). Among the synthesized compounds, the iodo compound 6 (ETN-6) exhibits higher anti-cancer activity compared to erlotinib. An efficient method is developed for the conjugation of erlotinib analogue-4, alcohol compound, with protein, bovine serum albumin (BSA), via succinic acid linker. The in vitro anti-tumor activity of the protein attached erlotinib analogue, 8 (ETN-4-Suc-BSA), showed stronger inhibitory activity in both A549 and H1975 NSCLC cell lines.

In Silico Identification of Novel Erlotinib Analogues Against Epidermal Growth Factor Receptor.

Cancer is one of the major health challenges in modern times. Considering its high mortality rate, many proteins that are linked to cancer have been targeted for therapy, with one of them being the epidermal growth factor receptor (EGFR). A drug that is currently in the market for the treatment of non-small cell lung cancer and targets EGFR is erlotinib. In a quest for improved efficacy of erlotinib, herein we report molecular docking studies of thirteen erlotinib analogues by modification of the alkyne and anilino groups, all of which displayed better binding affinity than erlotinib. We identified aziridinyl analogue (S)- 13B: with the best binding energy of all the analogues studied.