慢性肾小球肾炎患者血清UA、Cys C、TAFI联合检测的临床意义

目的:探讨血清尿酸(UA)、胱抑素C(Cys C)和凝血酶激活纤溶抑制物(TAFI)联合检测在慢性肾小球肾炎(CGN)早期诊断中的应用价值。方法:选取2016年10月-2018年10月青海省人民医院肾内科收治的CGN患者80例作为研究组,同时间段于我院行体检的健康志愿者70例作为对照组,比较两组间UA、Cys C、TAFI和肾小球滤过率(GFR)的水平变化,采用Pearson相关性分析CGN患者GFR与UA、Cys C、TAFI的相关性,采用受试者工作特征(ROC)曲线比较各指标及联合检测对CGN的诊断价值。结果:与对照组相比,研究组血清UA、Cys C、TAFI水平均升高,GFR降低,差异有统计学意义(P<0.05);Pearson相关性分析显示,CGN患者GFR与UA、Cys C、TAFI呈显著负相关(P<0.05);联合检测血清UA、Cys C、TAFI水平,诊断CGN的敏感度为86.3%,特异性为80.0%,均明显高于UA、Cys C、TAFI的单独应用。结论:CGN患者血清UA、Cys C、TAFI水平升高,三者联合检测有助于临床早期诊断CGN。     

Anti-proliferative potential of triphenyl substituted pyrimidines against MDA-MB-231, HCT-116 and HT-29 cancer cell lines

A series of triphenyl substituted pyrimidines as analogous of colchicine and combretastatin A-4 was synthesized and evaluated for the antiproliferative potential. The compounds were screened against MDA-MB-231, HCT-116 and HT-29 cell lines using MTT assay. Most of the compounds displayed antiproliferative activity in low to sub micro molar concentration. Amongst the synthesized derivatives, compounds HK-2, HK-10 and HK-13 were found to be effective against all the three cancer cell lines. HK-2 exhibited IC₅₀ values of 3.39 µM, 4.78 µM and 4.23 µM, HK-10 showed IC₅₀ values of 0.81 µM, 5.89 µM, 4.96 µM and HK-13 showed IC₅₀ values 3.24 µM, 4.93 µM and 4.73 µM against MDA-MB-231, HCT-116 and HT-29 cancer cell lines, respectively. HK-10 was found to be the most potent compound in the series with IC₅₀ values of 0.81 µM against MDA-MB-231. In the cell cycle analysis, HK-2 and HK-10 showed cell arrest at G2/M phase of the cell cycle while HK-13 inhibited cell growth at the G1/G0 phase. All the three compounds showed cell death induced through apoptosis. In the docking studies, HK-2, HK-10 and HK-13 were found to fit well in the colchicine binding site of the tubulin. Some of the compounds in the current series were found to be promising against all the three cancer cell lines and may act as potent leads for further development.     

Monoaryl derivatives as transthyretin fibril formation inhibitors: Design,synthesis, biological evaluation and structural analysis

Transthyretin (TTR) is a ß-sheet-rich homotetrameric protein that transports thyroxine (T4) and retinol both in plasma and in cerebrospinal fluid. TTR also interacts with amyloid-β, playing a protective role in Alzheimer’s disease. Dissociation of the native transthyretin (TTR) tetramer is widely accepted as the critical step in TTR amyloids fibrillogenesis, and is responsible for extracellular deposition of amyloid fibrils. Small molecules, able to bind in T4 binding sites and stabilize the TTR tetramer, are interesting tools to treat and prevent systemic ATTR amyloidosis. We report here the synthesis, in vitro evaluation and three-dimensional crystallographic analyses of new monoaryl-derivatives in complex with TTR. Of the derivatives reported here, the best inhibitor of TTR fibrillogenesis, 1d, exhibits an activity similar to diflunisal.     

Small-molecule active pharmaceutical ingredients of approved cancer therapeutics inhibit human aspartate/asparagine-β-hydroxylase

Human aspartate/asparagine-β-hydroxylase (AspH) is a 2-oxoglutarate (2OG) dependent oxygenase that catalyses the hydroxylation of Asp/Asn-residues of epidermal growth factor-like domains (EGFDs). AspH is reported to be upregulated on the cell surface of invasive cancer cells in a manner distinguishing healthy from cancer cells. We report studies on the effect of small-molecule active pharmaceutical ingredients (APIs) of human cancer therapeutics on the catalytic activity of AspH using a high-throughput mass spectrometry (MS)-based inhibition assay. Human B-cell lymphoma-2 (Bcl-2)-protein inhibitors, including the (R)-enantiomer of the natural product gossypol, were observed to efficiently inhibit AspH, as does the antitumor antibiotic bleomycin A₂. The results may help in the design of AspH inhibitors with the potential of increased selectivity compared to the previously identified Fe(II)-chelating or 2OG-competitive inhibitors. With regard to the clinical use of bleomycin A₂ and of the Bcl-2 inhibitor venetoclax, the results suggest that possible side-effects mediated through the inhibition of AspH and other 2OG oxygenases should be considered.     

Phenyltriazole-functionalized sulfamate inhibitors targeting tyrosyl- or isoleucyl-tRNA synthetase

Antimicrobial resistance is considered as one of the major threats for the near future as the lack of effective treatments for various infections would cause more deaths than cancer by 2050. The development of new antibacterial drugs is considered as one of the cornerstones to tackle this problem. Aminoacyl-tRNA synthetases (aaRSs) are regarded as good targets to establish new therapies. Apart from being essential for cell viability, they are clinically validated. Indeed, mupirocin, an isoleucyl-tRNA synthetase (IleRS) inhibitor, is already commercially available as a topical treatment for MRSA infections. Unfortunately, resistance developed soon after its introduction on the market, hampering its clinical use. Therefore, there is an urgent need for new cellular targets or improved therapies. Follow-up research by Cubist Pharmaceuticals led to a series of selective and in vivo active aminoacyl-sulfamoyl aryltetrazole inhibitors targeting IleRS (e.g. CB 168).Here, we describe the synthesis of new IleRS and TyrRS inhibitors based on the Cubist Pharmaceuticals compounds, whereby the central ribose was substituted for a tetrahydropyran ring. Various linkers were evaluated connecting the six-membered ring with the base-mimicking part of the synthesized analogues. Out of eight novel molecules, a three-atom spacer to the phenyltriazole moiety, which was established using azide-alkyne click chemistry, appeared to be the optimized linker to inhibit IleRS. However, 11 (K_i,app = 88 ± 5.3 nM) and 36a (K_i,app = 114 ± 13.5 nM) did not reach the same level of inhibitory activity as for the known high-affinity natural adenylate-intermediate analogue isoleucyl-sulfamoyl adenosine (IleSA, CB 138; K_i,app = 1.9 ± 4.0 nM) and CB 168, which exhibit a comparable inhibitory activity as the native ligand. Therefore, 11 was docked into the active site of IleRS using a known crystal structure of T. thermophilus in complex with mupirocin. Here, we observed the loss of the crucial 3′- and 4′- hydroxyl group interactions with the target enzyme compared to CB 168 and mupirocin, which we suggest to be the reason for the limited decrease in enzyme affinity. Despite the lack of antibacterial activity, we believe that structurally optimizing these novel analogues via a structure-based approach could ultimately result in aaRS inhibitors which would help to tackle the antibiotic resistance problem.     

Novel class of benzimidazole-thiazole hybrids: The privileged scaffolds of potent anti-inflammatory activity with dual inhibition of cyclooxygenase and 15-lipoxygenase enzymes

The present study includes design and synthesis of new molecular hybrids of 2-methylthiobenzimidazole linked to various anti-inflammatory pharmacophores through 2-aminothiazole linker, to investigate the effect of such molecular variation on cyclooxygenase (COX) and 15-lipoxygenase (15-LOX) enzymes inhibition as well as in vivo anti-inflammatory activity. The chemical structures of new hybrids were confirmed using different spectroscopic tools and elemental analyses. Benzimidazole-thiazole hybrids linked to acetyl moiety 13, phenyl thiosemicarbazone 14, 1,3-thiazolines 15a-c and 4-thiazolidinone 16 exhibited significant COX-2 inhibition (IC₅₀ = 0.045–0.075 µM) with significant COX-2 selectivity indices (SI = 142–294). All hybrids revealed potent 15-LOX inhibitory activity (IC₅₀ = 1.67–6.56 µM). Benzimidazole-thiazole hybrid 15b was the most potent dual COX-2 (IC₅₀ = 0.045 µM, SI = 294) inhibitor approximate to celecoxib (COX-2; IC₅₀ = 0.045 µM, SI = 327), with double inhibitory activity versus 15-LOX enzyme (IC₅₀ = 1.67 µM) relative to quercetin (IC₅₀ = 3.34 µM). Three hybrids (14, 15b & 16) were selected for in vivo screening using carrageenan-induced paw edema method. Benzimidazole-thiazole hybrid linked to 4-thiazolidinone 16 showed the maximum edema inhibition at both 3 h and 4 h intervals as well (~119% and 102% relative to indomethacin, respectively). The gastric ulcerogenic effect of benzimidazole-thiazole hybrid 16 was estimated compared with indomethacin showing superior gastrointestinal safety profile. In bases of molecular modeling; all new active hybrids were subjected to docking simulation into active sites of COX-2 and 15-LOX enzymes to study the binding mode of these novel potent dual COX-2/15-LOX inhibitors.     

Genomic and signalling pathway characterization of the NZM panel of melanoma cell lines: A valuable model for studying the impact of genetic diversity in melanoma

Melanoma is a disease associated with a very high mutation burden and thus the possibility of a diverse range of oncogenic mechanisms that allow it to evade therapeutic interventions and the immune system. Here, we describe the characterization of a panel of 102 cell lines from metastatic melanomas (the NZM lines), including using whole‐exome and RNA sequencing to analyse genetic variants and gene expression changes in a subset of this panel. Lines possessing all major melanoma genotypes were identified, and hierarchical clustering of gene expression profiles revealed four broad subgroups of cell lines. Immunogenotyping identified a range of HLA haplotypes as well as expression of neoantigens and cancer–testis antigens in the lines. Together, these characteristics make the NZM panel a valuable resource for cell‐based, immunological and xenograft studies to better understand the diversity of melanoma biology and the responses of melanoma to therapeutic interventions.     

Exposure of human intestinal epithelial cells and primary human hepatocytes to trypsin-like serine protease inhibitors with potential antiviral effect

Human intestinal epithelial cell line-6 (HIEC-6) cells and primary human hepatocytes (PHHs) were treated with 3-amidinophenylalanine-derived inhibitors of trypsin-like serine proteases for 24 hours. It was proven that treatment with MI-1900 and MI-1907 was tolerated up to 50 μM in HIEC-6. These inhibitors did not cause elevations in extracellular H₂O₂ levels and in the concentrations of interleukin (IL)-6 and IL-8 and did not alter occludin distribution in HIEC-6. It was also found that MI-1900 and MI-1907 up to 50 μM did not affect cell viability, IL-6 and IL-8 and occludin levels of PHH. Based on our findings, these inhibitors could be safely applicable at 50 μM in HIEC-6 and in PHH; however, redox status was disturbed in case of PHH. Moreover, it has recently been demonstrated that MI-1900 prevents the replication and spread of the new SARS-CoV-2 in infected Calu-3 cells, most-likely via an inhibition of the membrane-bound host protease TMPRSS2.