dasatinib and Neoplasms

Cancer has been the second heath killer being next only to cardiovascular diseases in human society. Although many efforts have been taken for cancer therapy and many achievements have been yielded in the diagnosis and treatment of cancer, the current first-line anti-cancer agents are insufficient owing to the emergence of multi-drug resistance and side effects. Therefore, it is urgent to develop new anti-cancer agents with high activity and low toxicity. 2-Aminothiazole is a class of important scaffold which widely distributes in many natural and synthetic compounds with many pharmacological effects including the potential anti-cancer activity. In this review, we summarized the recent progress of 2-aminothiazole as a privileged scaffold for the discovery of anti-cancer agents based on biological targets, such as tubulin protein, histone acetylase/histone deacetylase (HAT/HDAC), phosphatidylinositol 3-kinases (PI3Ks), Src/Abl kinase, BRAF kinase, epidermal growth factor receptor (EGFR) kinase and sphingosine kinase (SphK), and also investigated the structure-activity relationships (SARs) of most compounds. It is believed that this review could be helpful for medicinal chemists in the discovery of more anti-cancer agents bearing 2-aminothiazole scaffold with excellent activity and high therapeutic index.

Topics: Animals; Antineoplastic Agents; Drug Design; Drug Discovery; Humans; Neoplasms; Protein Kinase Inhibitors; Structure-Activity Relationship; Thiazoles; Tubulin Modulators

Discoidin domain receptors (DDRs) are members of the transmembrane receptor tyrosine kinase (RTK) superfamily which are distinguished from others by the presence of a discoidin motif in the extracellular domain and their utilization of collagens as internal ligands. Two types of DDRs, DDR1 and DDR2, have been identified with distinct expression profiles and ligand specificities. These DDRs play important roles in the regulation of fundamental cellular process, such as proliferation, survival, differentiation, adhesion, and matrix remodeling. They have also been closely linked to a number of human diseases, including various fibrotic disorders, atherosclerosis, and cancer. As a consequence, DDRs have been considered as novel potential molecular targets for drug discovery and increasing efforts are being devoted to the identification of new small molecule inhibitors targeting the receptors. In this review, we offer a contemporary overview on the discovery of DDRs inhibitors and their potential medical application for the treatment of cancer and inflammation related disorders.

Topics: Amino Acid Sequence; Animals; Discoidin Domain Receptors; Drug Discovery; Humans; Inflammation; Ligands; Models, Molecular; Molecular Sequence Data; Neoplasms; Protein Conformation; Protein Kinase Inhibitors; Receptor Protein-Tyrosine Kinases; Receptors, Mitogen; Small Molecule Libraries

Protein degradation is a promising strategy for drug development. Proteolysis-targeting chimeras (PROTACs) hijacking the E3 ligase cereblon (CRBN) exhibit enormous potential and universal degradation performance due to the small molecular weight of CRBN ligands. In this study, the CRBN-recruiting PROTACs were explored on the degradation of oncogenic fusion protein BCR-ABL, which drives the pathogenesis of chronic myeloid leukemia (CML). A series of novel PROTACs were synthesized by conjugating BCR-ABL inhibitor dasatinib to the CRBN ligand including pomalidomide and lenalidomide, and the extensive structure-activity relationship (SAR) studies were performed focusing on optimization of linker parameters. Therein, we uncovered that pomalidomide-based degrader 17 (SIAIS056), possessing sulfur-substituted carbon chain linker, exhibits the most potent degradative activity in vitro and favorable pharmacokinetics in vivo. Besides, degrader 17 also degrades a variety of clinically relevant resistance-conferring mutations of BCR-ABL. Furthermore, degrader 17 induces significant tumor regression against K562 xenograft tumors. Our study indicates that 17 as an efficacious BCR-ABL degrader warrants intensive investigation for the future treatment of BCR-ABL

Topics: Animals; Cell Proliferation; Dasatinib; Drug Design; Fusion Proteins, bcr-abl; Half-Life; Humans; K562 Cells; Lenalidomide; Ligands; Mice; Neoplasms; Protein Kinase Inhibitors; Proteolysis; Structure-Activity Relationship; Thalidomide; Transplantation, Heterologous; Ubiquitin-Protein Ligases

Topics: Animals; Antineoplastic Agents; Aurora Kinase A; Aurora Kinase B; Azepines; Cell Line, Tumor; Humans; Mice; Mice, Nude; Neoplasms; Protein Kinase Inhibitors; Pyrazoles; Vascular Endothelial Growth Factor Receptor-2

The tyrosine kinase ACK1, a critical signal transducer regulating survival of hormone-refractory cancers, is an important therapeutic target, for which there are no selective inhibitors in clinical trials to date. This work reports the discovery of novel and potent inhibitors for ACK1 tyrosine kinase (also known as TNK2) using an innovative fragment-based approach. Focused libraries were designed and synthesized by selecting fragments from reported ACK inhibitors to create hybrid structures in a mix and match process. The hybrid library was screened by enzyme-linked immunosorbent assay-based kinase inhibition and (33)P HotSpot assays. Systematic structure-activity relationship studies led to the identification of compound (R)-9b, which shows potent in vitro (IC50 = 56 nM, n = 3, (33)P HotSpot assay) and in vivo (IC50 < 2 μM, human cancer cell lines) ACK1 inhibition. Both (R)-9b and (S)-9b were stable in human plasma and displayed a long half-life (t(1/2) > 6 h).

Topics: Antineoplastic Agents; Cell Line, Tumor; Drug Design; Humans; Molecular Docking Simulation; Neoplasms; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Small Molecule Libraries; Structure-Activity Relationship

The emergence of drug resistance remains a fundamental challenge in the development of kinase inhibitors that are effective over long-term treatments. Allosteric inhibitors that bind to sites lying outside the highly conserved ATP pocket are thought to be more selective than ATP-competitive inhibitors and may circumvent some mechanisms of drug resistance. Crystal structures of type I and allosteric type III inhibitors in complex with the tyrosine kinase cSrc allowed us to employ principles of structure-based design to develop these scaffolds into potent type II kinase inhibitors. One of these compounds, 3c (RL46), disrupts FAK-mediated focal adhesions in cancer cells via direct inhibition of cSrc. Details gleaned from crystal structures revealed a key feature of a subset of these compounds, a surprising flexibility in the vicinity of the gatekeeper residue that allows these compounds to overcome a dasatinib-resistant gatekeeper mutation emerging in cSrc.

Topics: Allosteric Site; Animals; Cell Line; Crystallography, X-Ray; CSK Tyrosine-Protein Kinase; Drug Design; Drug Resistance, Neoplasm; Focal Adhesions; Humans; Mutation, Missense; Neoplasms; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Proto-Oncogene Proteins; Pyrazoles; src-Family Kinases; Structure-Activity Relationship; Urea

To realize the full potential of targeted protein kinase inhibitors for the treatment of cancer, it is important to address the emergence of drug resistance in treated patients. Mutant forms of BCR-ABL, KIT, and the EGF receptor (EGFR) have been found that confer resistance to the drugs imatinib, gefitinib, and erlotinib. The mutations weaken or prevent drug binding, and interestingly, one of the most common sites of mutation in all three kinases is a highly conserved "gatekeeper" threonine residue near the kinase active site. We have identified existing clinical compounds that bind and inhibit drug-resistant mutant variants of ABL, KIT, and EGFR. We found that the Aurora kinase inhibitor VX-680 and the p38 inhibitor BIRB-796 inhibit the imatinib- and BMS-354825-resistant ABL(T315I) kinase. The KIT/FLT3 inhibitor SU-11248 potently inhibits the imatinib-resistant KIT(V559D/T670I) kinase, consistent with the clinical efficacy of SU-11248 against imatinib-resistant gastrointestinal tumors, and the EGFR inhibitors EKB-569 and CI-1033, but not GW-572016 and ZD-6474, potently inhibit the gefitinib- and erlotinib-resistant EGFR(L858R/T790M) kinase. EKB-569 and CI-1033 are already in clinical trials, and our results suggest that they should be considered for testing in the treatment of gefitinib/erlotinib-resistant non-small cell lung cancer. The results highlight the strategy of screening existing clinical compounds against newly identified drug-resistant mutant variants to find compounds that may serve as starting points for the development of next-generation drugs, or that could be used directly to treat patients that have acquired resistance to first-generation targeted therapy.

Topics: Aminoquinolines; Aniline Compounds; Cell Line; Drug Resistance, Neoplasm; ErbB Receptors; Humans; Indoles; Kinetics; Morpholines; Mutation; Naphthalenes; Neoplasms; Oncogene Proteins v-abl; Organic Chemicals; Piperazines; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-kit; Pyrazoles; Pyrroles; Sunitinib