FLT3 kinase is a potential drug target in acute myeloid leukemia (AML). Patients with FLT3 mutations typically have higher relapse rates and worse outcomes than patients without FLT3 mutations. In this study, we investigated the suitability of various heterocycles as central cores of FLT3 inhibitors, including thieno[3,2-d]pyrimidine, pyrazolo[1,5-a]pyrimidine, imidazo[4,5-b]pyridine, pyrido[4,3-d]pyrimidine, and imidazo[1,2-b]pyridazine. Our assays revealed a series of imidazo[1,2-b]pyridazines with high potency against FLT3. Compound 34f showed nanomolar inhibitory activity against recombinant FLT3-ITD and FLT3-D835Y (IC50 values 4 and 1 nM, respectively) as well as in the FLT3-ITD-positive AML cell lines MV4-11, MOLM-13, and MOLM-13 expressing the FLT3-ITD-D835Y mutant (GI50 values of 7, 9, and 4 nM, respectively). In contrast, FLT3-independent cell lines were much less sensitive. In vitro experiments confirmed suppression of FLT3 downstream signaling pathways. Finally, the treatment of MV4-11 xenograft-bearing mice with 34f at doses of 5 and 10 mg/kg markedly blocked tumor growth without any adverse effects.

• MeSH
• akutní myeloidní leukemie * patologie   MeSH
• apoptóza MeSH
• inhibitory proteinkinas farmakologie   terapeutické užití   MeSH
• lidé MeSH
• mutace MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• protinádorové látky * farmakologie   terapeutické užití   MeSH
• pyridaziny * farmakologie   terapeutické užití   MeSH
• pyrimidiny farmakologie   MeSH
• tyrosinkinasa 3 podobná fms genetika   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• FLT3 protein, human MeSH Prohlížeč
• inhibitory proteinkinas MeSH
• protinádorové látky * MeSH
• pyridazine MeSH Prohlížeč
• pyridaziny * MeSH
• pyrimidiny MeSH
• tyrosinkinasa 3 podobná fms MeSH

Cyclin-dependent kinases (CDKs) play an important role in the cell-division cycle. Synthetic inhibitors of CDKs are based on 2,6,9-trisubstituted purines and are developed as potential anticancer drugs; however, they have low solubility in water. In this study, we proved that the pharmaco-chemical properties of purine-based inhibitors can be improved by appropriate substitution with the adamantane moiety. We prepared ten new purine derivatives with adamantane skeletons that were linked at position 6 using phenylene spacers of variable geometry and polarity. We demonstrated that the adamantane skeleton does not compromise the biological activity, and some of the new purines displayed even higher inhibition activity towards CDK2/cyclin E than the parental compounds. These findings were supported by a docking study, which showed an adamantane scaffold inside the binding pocket participating in the complex stabilisation with non-polar interactions. In addition, we demonstrated that β-cyclodextrin (CD) increases the drug's solubility in water, although this is at the cost of reducing the biochemical and cellular effect. Most likely, the drug concentration, which is necessary for target engagement, was decreased by competitive drug binding within the complex with β-CD.

• Klíčová slova
• 2,6,9-trisubstituted purine, adamantane, cyclin-dependent kinase, cytotoxicity, molecular docking, β-cyclodextrin,
• MeSH
• adamantan chemie   MeSH
• beta-cyklodextriny chemie   MeSH
• buňky K562 MeSH
• cyklin-dependentní kinasa 2 antagonisté a inhibitory   MeSH
• inhibitory proteinkinas farmakologie   MeSH
• lidé MeSH
• MFC-7 buňky MeSH
• protinádorové látky chemie   farmakologie   MeSH
• puriny chemie   MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• adamantan MeSH
• beta-cyklodextriny MeSH
• CDK2 protein, human MeSH Prohlížeč
• cyklin-dependentní kinasa 2 MeSH
• inhibitory proteinkinas MeSH
• protinádorové látky MeSH
• puriny MeSH

We designed, synthesized, and evaluated novel 2,6,9-trisubstituted purine derivatives for their prospective role as antitumor compounds. Using simple and efficient methodologies, 31 compounds were obtained. We tested these compounds in vitro to draw conclusions about their cell toxicity on seven cancer cells lines and one non-neoplastic cell line. Structural requirements for antitumor activity on two different cancer cell lines were analyzed with SAR and 3D-QSAR. The 3D-QSAR models showed that steric properties could better explain the cytotoxicity of compounds than electronic properties (70% and 30% of contribution, respectively). From this analysis, we concluded that an arylpiperazinyl system connected at position 6 of the purine ring is beneficial for cytotoxic activity, while the use of bulky systems at position C-2 of the purine is not favorable. Compound 7h was found to be an effective potential agent when compared with a currently marketed drug, cisplatin, in four out of the seven cancer cell lines tested. Compound 7h showed the highest potency, unprecedented selectivity, and complied with all the Lipinski rules. Finally, it was demonstrated that 7h induced apoptosis and caused cell cycle arrest at the S-phase on HL-60 cells. Our study suggests that substitution in the purine core by arylpiperidine moiety is essential to obtain derivatives with potential anticancer activity.

• Klíčová slova
• 3D-QSAR, apoptosis, cancer, cell cycle, cytotoxicity, purine derivatives,
• MeSH
• apoptóza účinky léků   MeSH
• kontrolní body fáze S buněčného cyklu účinky léků   MeSH
• krystalografie rentgenová MeSH
• kvantitativní vztahy mezi strukturou a aktivitou * MeSH
• lidé MeSH
• molekulární konformace MeSH
• nádorové buněčné linie MeSH
• protinádorové látky chemická syntéza   chemie   farmakologie   MeSH
• puriny chemická syntéza   chemie   farmakologie   MeSH
• screeningové testy protinádorových léčiv MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• protinádorové látky MeSH
• purine MeSH Prohlížeč
• puriny MeSH

An analog of aromatic cytokinins, the 2,6,9-trisubstituted purine derivative bohemine, was applied to cultures of mouse hybridoma cells in order to analyze its capacity of suppressing cell growth and maintaining or enhancing the production of monoclonal antibody. Addition of bohemine at concentrations in the range of1-10 muM resulted in a short-term arrest of growth and of monoclonal antibody production. The short-term suppression of cell functions was followed by a significant temporary increase of specific growth rate and of specific production rate. The steady-state viable cell density values, found in semicontinuous cultures, showed a certain stimulation of cell growth in the range of micromolar concentrations of bohemine, and inhibition of growth at 10 and 30 muM concentrations. The profiles of cell cycle phases indicated that hybridoma cells are retarded both at the G(1)/S boundary and at the G(2)/M boundary, depending on bohemine concentration. The existence of the sequence of events,from suppression to stimulation, suggests that bohemine probably modulates more than one regulatory pathway in the cell.

• Publikační typ
• časopisecké články MeSH