Discovery of Pyrazolo[1,5-a]pyridine Derivatives as Potent and Selective PI3Kγ/δ Inhibitors.

PI3Kγ and PI3Kδ plays critical roles in exerting immunosuppression by targeting regulatory T cells and myeloid cells. Dual inhibition of PI3Kγ and PI3Kδ has emerged as a novel therapeutic strategy for cancer immunotherapy. We herein report a series of pyrazolopyridine derivatives with distinct scaffolds as potent and selective dual inhibitors of PI3Kγ and PI3Kδ. Among them, 20e (IHMT-PI3K-315) displays an IC50 value of 4.0 and 9.1 nM against PI3Kγ and PI3Kδ respectively in biochemical assays. Meanwhile, it potently inhibits PI3Kγ and PI3Kδ-mediated phosphorylation of AKT S473 with EC50 values of 0.028 and 0.013 µM in cellular assays. In addition, 20e exhibits a favorable selectivity profile in protein kinases at 1 µM. In bone marrow-derived macrophages (BMDM), 20e can repolarize the M2 phenotype to the M1 phenotype. In vivo, 20e demonstrates acceptable pharmacokinetic properties and suppresses tumor growth in a MC38 syngeneic mouse model.

Discovery of Pyrazolo[1,5-a]pyrimidine derivative as a potent and selective PI3Kγ/δ dual inhibitor.

Phosphoinositol 3-kinases (PI3Ks) γ and δ are primarily expressed in leukocytes and play crucial roles in regulation of the immune system. Dual inhibition of PI3Kγ/δ has emerged as an effective approach to regulate the tumor microenvironment. Here, we report the exploration of structure-activity relationship optimization which led to the discovery of a potent PI3Kγ/δ dual inhibitor 15u (IHMT-PI3K-455). 15u exhibits strong potency in biochemical and cellular assays and it repolarizes M2 phenotype toward M1 phenotype in THP-1 and BMDM macrophages. In addition, it shows suitable in vivo properties as demonstrated through pharmacokinetic studies in rats and pharmacodynamics properties in a MC38 xenograft model.

Exosome miR-3184-5p inhibits gastric cancer growth by targeting XBP1 to regulate the AKT, STAT3, and IRE1 signalling pathways.

MicroRNAs can regulate the transcription of protein-coding genes associated with the development and progression of cancer. In this study, we explored the potential diagnostic function of exosome miR-3184-5p in gastric cancer. This exosome was isolated from the blood samples of 150 patients with gastric cancer and 60 healthy participants. The mean particle size and concentration of serum exosome in the patients with gastric cancer were 104.6 nm (93.97-115.84) and 6.21e+009 particles/ml (5.15e+009-7.12e+009), respectively. miR-3184-5p expression was substantially downregulated in the patients with gastric cancer compared with that in the healthy participants. The gastric cancer cell line HGC-27 was cultured and transfected with the mimic and an inhibitor to overexpress and inhibit miR-3184-5p expression. miR-3184-5p strongly suppressed cell proliferation, migration, and invasion but induced cell apoptosis. Luciferase reporter assay revealed that XBP1 was the target of miR-3184-5p. miR-3184-5p substantially downregulated the expression of CD44, cyclin D1, MMP2, p65, p-AKT, and p-STAT3 but upregulated that of GRP78, IRE1, p-JNK, and CHOP. Moreover, miR-3184-5p cleaved caspase-12 and inhibited BCL-2 expression. These results suggested that the downregulation of miR-3184-5p in patients with gastric cancer might regulate the AKT, STAT3, and IRE1 pathways to promote the vitality of gastric cancer cells.

Discovery of Pyrrolo[2,3-d]pyrimidine derivatives as potent and selective colony stimulating factor 1 receptor kinase inhibitors.

Colony stimulating factor 1 receptor kinase (CSF1R) plays an integral role in tumor-associated macrophage repolarization and has emerged as a novel therapeutic target for cancer immunotherapy. Most of the current CSF1R kinase inhibitors lack selectivity between CSF1R kinase and other type III growth factor receptor members. Herein, we report a potent and selective CSF1R inhibitor 18h, which displays an IC50 value of 5.14 nM against CSF1R and achieves selectivity over other type III receptor tyrosine kinases (>38-fold). 18h inhibits the phosphorylation of CSF1R and its downstream signaling pathway in RAW264.7, THP-1, and M-NFS-60 cells. Treatment with this compound leads to alteration of the macrophage polarization in RAW264.7 macrophages in a dose-dependent manner. In vivo, 18h demonstrates acceptable pharmacokinetic profiles and suppresses the tumor growth in a mouse xenograft model inoculated with M-NFS-60 cells.

The Association of ADRB1 and CYP2D6 Polymorphisms With Antihypertensive Effects and Analysis of Their Contribution to Hypertension Risk.

BACKGROUND: Genetic factors have a vital influence on the pathogenesis of hypertension. In this retrospective study, we aimed to evaluate the association of ADRB1 and CYP2D6 polymorphisms with antihypertensive effects and perform an analysis of their contribution to hypertension risk. METHODS: A total of 261 healthy individuals and 261 essential hypertension patients treated with metoprolol for 12 weeks were enrolled. ADRB1 and CYP2D6 genotypes were identified by xTAG liquid chip technology. We used multivariate logistic regression and a generalized linear mixed model to assess hypertension-related risk factors. RESULTS: The allele frequencies of ADRB1 and CYP2D6 variants were 59.8% and 64.6% in the essential hypertension group and 70.3% and 65.9% in the controls, respectively. The genotype and allele distribution of ADRB1 were significantly different between the 2 groups (P < 0.05), but there was no significant difference in CYP2D6 distribution (P = 0.91 and 0.88). By logistic regression analysis, high fasting plasma glucose, smoking, high triglyceride and the Gly/Gly polymorphism in Arg389Gly ADRB1 all emerged as independent risk factors for hypertension. Additionally, the ADRB1 genotype played a major role in the antihypertensive effect of metoprolol and the patients with the Gly389Gly genotype showed a significantly better response to metoprolol than did those with a heterozygous ADRB1 mutation (Arg389Gly) (P = 0.027). CONCLUSIONS: The results demonstrate that Gly/Gly polymorphism in Arg389Gly ADRB1 was an independent risk factor together with high fasting plasma glucose, smoking and high triglyceride; moreover, the patients who carried the Gly389Gly genotype had a significantly improved metoprolol antihypertensive effect than those with ADRB1.

Associations between ADRB1 and CYP2D6 gene polymorphisms and the response to ß-blocker therapy in hypertension.

OBJECTIVE: To investigate the associations between ß1-adrenergic receptor (ADRB1) and cytochrome P450 2D6 (CYP2D6) gene polymorphisms and ß-blocker treatment outcomes in patients with hypertension. METHODS: Chinese patients with essential hypertension were treated with the ß-blocker metoprolol and followed up for 12 weeks. xTAG® liquid-chip technology was used for CYP2D6 100 C > T and ADRB1 1165G > C genotyping. Associations between gene polymorphisms and antihypertensive therapy outcomes were assessed by generalized linear model fitting. A decrease of ≥ 10 mmHg in systolic blood pressure indicated an effective treatment outcome. RESULTS: A total of 93 patients were included in the study. Mutant allele frequencies of 61.29% and 58.60% were obtained for ADRB1 and CYP2D6, respectively. There was no significant interaction between the effects of ADRB1 and CYP2D6 gene polymorphisms on treatment outcome. Patients homozygous for the mutant ADRB1 genotype (CC) had better treatment outcomes than those heterozygous for the mutation (GC). Interestingly, ß-blocker treatment duration was an independent factor associated with treatment outcome. CONCLUSIONS: The ADRB1 1165G > C gene polymorphism and ß-blocker treatment duration are independent factors associated with ß-blocker treatment outcome. These findings suggest that the selection of antihypertensive therapy should take into consideration the patient's genotype.