gsk-461364 and Carcinoma--Non-Small-Cell-Lung

To investigate the effects of PLK1 inhibitors on osimertinib-resistant non-small cell lung carcinoma (NSCLC) cells and the anti-tumor effect combined with osimertinib.. An osimertinib resistant NCI-H1975 cell line was induced by exposure to gradually increasing drug concentrations. Osimertinib-resistant cells were co-treated with compounds from classical tumor pathway inhibitor library and osimertinib to screen for compounds with synergistic effects with osimertinib. The Gene Set Enrichment Analysis (GSEA) was used to investigate the activated signaling pathways in osimertinib-resistant cells; sulforhodamine B (SRB) staining was used to investigate the effect of PLK1 inhibitors on osimertinib-resistant cells and the synergistic effect of PLK1 inhibitors combined with osimertinib.. Osimertinib-resistance in NCI-H1975 cell (resistance index=43.45) was successfully established. The PLK1 inhibitors GSK 461364 and BI 2536 had synergistic effect with osimertinib. Compared with osimertinib-sensitive cells, PLK1 regulatory pathway and cell cycle pathway were significantly activated in osimertinib-resistant cells. In NSCLC patients with epidermal growth factor receptor mutations treated with osimertinib,. PLK1 inhibitors have a synergistic effect with osimertinib on osimertinib-resistant NSCLC cells which indicates that they may have potential clinical value in the treatment of NSCLC patients with osimertinib resistance.

Topics: Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Drug Resistance, Neoplasm; ErbB Receptors; Humans; Lung Neoplasms; Mutation

To identify new therapeutic targets for non-small cell lung cancer (NSCLC), we systematically searched two cancer cell line databases for sensitivity data on a broad range of drugs. We identified polo-like kinase 1 (PLK1) as the most promising target for further investigation based on a subset of sensitive NSCLC cell lines and inhibitors that were in advanced clinical development.. To identify potential biomarkers of response of NSCLC to PLK1 inhibition and mechanisms of PLK1 inhibitor-induced apoptosis, integrated analysis of gene and protein expression, gene mutations, and drug sensitivity was performed using three PLK1 inhibitors (volasertib, BI2536, and GSK461364) with a large panel of NSCLC cell lines.. The NSCLC cell lines had different sensitivities to PLK1 inhibition, with a minority demonstrating sensitivity to all three inhibitors. PLK1 inhibition led to G2-M arrest, but only treatment-sensitive cell lines underwent substantial apoptosis following PLK1 inhibition. NSCLC lines with high epithelial-mesenchymal transition (EMT) gene signature scores (mesenchymal cell lines) were more sensitive to PLK1 inhibition than epithelial lines (P< 0.02). Likewise, proteomic profiling demonstrated that E-cadherin expression was higher in the resistant cell lines than in the sensitive ones (P< 0.01). Induction of an epithelial phenotype by expression of the miRNA miR-200 increased cellular resistance to PLK1 inhibition. Also, KRAS mutation and alterations in the tight-junction, ErbB, and Rho signaling pathways correlated with drug response of NSCLC.. In this first reported large-scale integrated analysis of PLK1 inhibitor sensitivity, we demonstrated that EMT leads to PLK1 inhibition sensitivity of NSCLC cells. Our findings have important clinical implications for mesenchymal NSCLC, a significant subtype of the disease that is associated with resistance to currently approved targeted therapies.

Topics: Animals; Apoptosis; Benzimidazoles; Carcinoma, Non-Small-Cell Lung; Cell Cycle Checkpoints; Cell Cycle Proteins; Cell Line, Tumor; Chromosomal Instability; Disease Models, Animal; Drug Resistance, Neoplasm; Epithelial-Mesenchymal Transition; Humans; Lung Neoplasms; Mice; Mutation; Polo-Like Kinase 1; Protein Kinase Inhibitors; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins; Proto-Oncogene Proteins p21(ras); Pteridines; Thiophenes; Tumor Burden; Xenograft Model Antitumor Assays