Discovery and Optimization of a Novel 2H-Pyrazolo[3,4-d]pyrimidine Derivative as a Potent Irreversible Pan-Fibroblast Growth Factor Receptor Inhibitor

Discovery and Structural Optimization of Novel Quinolone Derivatives as Potent Irreversible Pan-Fibroblast Growth Factor Receptor Inhibitors for Treating Solid Tumors

Aberrant activation of fibroblast growth factor receptors (FGFRs) has been identified as an oncogenic driver force for multiple cancer types, making FGFRs a compelling target for anticancer therapy. Because of the renewed interest in irreversible inhibitors, considerable efforts have been made to find irreversible FGFR inhibitors. Herein, we discovered a series of novel quinolone-based covalent pan-FGFR inhibitors by further optimizing the lead compound (lenvatinib) under the guidance of molecular docking. The representative pan-FGFR inhibitor I-5 exhibited significant inhibitory potency against FGFR1-4 with nanomolar activity and effectively suppressed the proliferation of Huh-7 and Hep3B HCC cells. I-5 displayed high selectivity against a panel of 369 kinases at 1 μM. The irreversible binding to target proteins was characterized by liquid chromatography and tandem mass spectrometry (LC-MS/MS). Moreover, I-5 exhibited favorable PK properties in vivo and induced significant TGI in the Huh-7 and NCI-H1581 xenograft mouse models.

Synthesis, Biological Evaluation, DNA Binding, and Molecular Docking of Hybrid 4,6-Dihydrazone Pyrimidine Derivatives as Antitumor Agents

In the present paper, on the basis of molecular hybridization, a series of 4,6-dihydrazone pyrimidine derivatives containing the pyridine moiety were synthesized, structurally characterized, and evaluated in vitro for their antitumor activity. According to the results, all the tested compounds demonstrated broad-spectrum antitumor activity against selected tumor cell lines (MCF-7, BGC-823, A549, and BEL-7402) and no obvious toxicity toward normal cells HL-7702. In particular, compounds 10a and 10f were found to be the most promising antitumor agents among the tested compounds against BGC-823 cells (IC₅₀ = 9.00 μM and 7.89 μM) and BEL-7402 cells (IC₅₀ = 6.70 μM and 7.66 μM), respectively. Compounds 10a and 10f exhibited higher potency against BGC-823 and BEL-7402 than the positive control 5-FU (IC₅₀ = 15.18 μM and 15.81 μM). Further mechanism investigations demonstrated that compounds 10a and 10f could significantly increase the level of cellular ROS and induce early apoptosis of BGC-823 cells in a dose-dependent manner. Moreover, the DNA binding results from UV/Vis, CD spectroscopy, and molecular docking studies indicated that 10a and 10f bind with DNA via groove binding and partial intercalation. These results demonstrated that 10a and 10f may serve as novel lead compounds for the discovery of more dihydrazone pyrimidine derivatives with improved antitumor potency and selectivity.

Signaling Pathway and Small-Molecule Drug Discovery of FGFR: A Comprehensive Review

Targeted therapy is a groundbreaking innovation for cancer treatment. Among the receptor tyrosine kinases, the fibroblast growth factor receptors (FGFRs) garnered substantial attention as promising therapeutic targets due to their fundamental biological functions and frequently observed abnormality in tumors. In the past 2 decades, several generations of FGFR kinase inhibitors have been developed. This review starts by introducing the biological basis of FGF/FGFR signaling. It then gives a detailed description of different types of small-molecule FGFR inhibitors according to modes of action, followed by a systematic overview of small-molecule-based therapies of different modalities. It ends with our perspectives for the development of novel FGFR inhibitors.

Design, Synthesis and Biological Evaluation of Novel Pyrazolo[1,2,4]triazolopyrimidine Derivatives as Potential Anticancer Agents

Three novel pyrazolo-[4,3-e][1,2,4]triazolopyrimidine derivatives (1, 2, and 3) were designed, synthesized, and evaluated for their in vitro biological activity. All three compounds exhibited different levels of cytotoxicity against cervical and breast cancer cell lines. However, compound 1 showed the best antiproliferative activity against all tested tumor cell lines, including HCC1937 and HeLa cells, which express high levels of wild-type epidermal growth factor receptor (EGFR). Western blot analyses demonstrated that compound 1 inhibited the activation of EGFR, protein kinase B (Akt), and extracellular signal-regulated kinase (Erk)1/2 in breast and cervical cancer cells at concentrations of 7 and 11 µM, respectively. The results from docking experiments with EGFR suggested the binding of compound 1 at the ATP binding site of EGFR. Furthermore, the crystal structure of compound 3 (7-(4-bromophenyl)-9-(pyridin-4-yl)-7H-pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidine) was determined by single crystal X-ray analysis. Our work represents a promising starting point for the development of a new series of compounds targeting EGFR.