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1.
Cancer Sci ; 114(4): 1229-1239, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36601880

ABSTRACT

Immune checkpoint inhibitors (ICIs) have become important treatment strategies, yet responses vary among patients and predictive biomarkers are urgently needed. Mutations in KMT2C and KMT2D lead to increased levels of genomic instability. Therefore, we aimed to examine whether KMT2C/D mutations might be a predictor of immunotherapeutic efficacy. Here, we investigated the associations of KMT2C/D loss-of-function (LOF) variants with tumor mutation burden (TMB), MSI-H, PD-L1 expression, the levels of tumor-infiltrating leukocytes (TILs), and clinical response to ICIs. It was found that KMT2C/D LOF variants were associated with higher TMB. Compared with the non-LOF group, the proportion of patients with MSI-H tumors was larger in the LOF group. PD-L1 expression was higher in the LOF group only for colorectal cancer in both the Chinese and The Cancer Genome Atlas cohorts. Importantly, KMT2C/D LOF variants were associated with decreased regulatory T cells and increased levels of CD8+ T cells, activated NK cells, M1 macrophages, and M2 macrophages in colorectal cancer. However, there was no significant association between KMT2C/D LOF and TILs levels in other cancer types. Consistently, the results showed that KMT2C/D LOF variants were associated with prolonged overall survival only in colorectal cancer (p = 0.0485). We also presented that patients with KMT2C/D LOF mutations exhibited a better clinical response to anti-PD-1 therapy in a Chinese colorectal cancer cohort (p = 0.002). Taken together, these results suggested that KMT2C/D LOF variants could be a useful predictor for ICIs efficacy in colorectal cancer. In addition, the predictive value of KMT2C/D LOF variants was consistent with their association with TILs levels.


Subject(s)
B7-H1 Antigen , Colorectal Neoplasms , Humans , B7-H1 Antigen/genetics , Immune Checkpoint Inhibitors/therapeutic use , CD8-Positive T-Lymphocytes , Mutation , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/genetics , Biomarkers, Tumor/genetics , Microsatellite Instability
2.
Genes Chromosomes Cancer ; 61(9): 530-541, 2022 09.
Article in English | MEDLINE | ID: mdl-35396765

ABSTRACT

The incidence of primary and acquired BRAF mutations is low in non-small cell lung cancer (NSCLC), with limited demographic and treatment outcome data available for this patient population. We evaluated lung cancer samples with programmed cell death ligand 1 (PD-L1) information extracted from 12 051 cases (cohort A) of lung cancer from OncoPanscan™-based sequencing of tissue (Genetron Health) and conducted retrospective multicenter data analysis using the database of Zhejiang Cancer Hospital and four other centers (cohort B, including 73 primary BRAF mutation and 14 acquired BRAF mutation cases) to compare treatment outcomes of patient groups with primary and acquired BRAF mutations. In cohort A, after propensity score analysis, 165 samples of NSCLC with BRAF mutations were screened along with 165 paired non-BRAF mutation samples. We observed no significant differences in the proportion of samples with ≥1% PD-L1 between BRAF and non-BRAF mutant groups. The median progression-free survival (mPFS) period in 13 patients with primary BRAF mutations receiving BRAF tyrosine kinase inhibitors (BRAF-TKIs) was 7.0 months. The group with primary BRAF mutations receiving immune checkpoint inhibitor (ICI) combination chemotherapy had better PFS than those administered ICI monotherapy (14.77 months vs. 5.0 months, p = 0.025) and similar results were obtained for OS (unreached vs. 20.3 months, p = 0.013). For acquired BRAF mutations, mPFS of BRAF-TKI, ICI-based, and chemotherapy-based regimens were 3.8, 1.5, and 1.9 months, respectively. Therefore, for patients with the primary BRAF V600E mutation, targeted therapy or immunochemotherapy could serve as effective treatment choices, while for those with acquired BRAF V600E, targeted drug therapy may remain the preferred solution in China.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , B7-H1 Antigen/genetics , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Mutation , Proto-Oncogene Proteins B-raf/genetics , Retrospective Studies , Treatment Outcome
3.
Int J Cancer ; 151(8): 1382-1393, 2022 10 15.
Article in English | MEDLINE | ID: mdl-35567574

ABSTRACT

Microsatellite instability (MSI) is an important biomarker for predicting the response to immunotherapy and prognosis that mainly results from a defective DNA mismatch repair (MMR) system and strongly correlates with high tumor mutation burden (TMB). Herein, we developed a novel method that integrates MSI score, MMR mutation status and TMB level to identify MSI status from next-generation sequencing (NGS) data. The novel method displays a sensitivity of 96.80%, a specificity of 99.96% and an overall accuracy of 99.89%, compared to current standards. Using our novel method, we analyzed 11 395 Chinese patients across 30 cancer types. High microsatellite instability (MSI-H) was detected in 210 (1.84%) samples in 18 of 30 cancer types assessed. Mutations in ACVR2A (73%), KMT2D (68%), KMT2B (66%) and MMR-related genes (MLH1, MSH2, MSH6 and PMS2) were enriched in MSI-H samples. Furthermore, MSI-H samples were more likely to have high TMB (P < .01), high PD-L1 expression (P < .05) and more tumor-infiltrating immune cells than microsatellite-stable (MSS) samples. Compared to the TCGA patients, the prevalence of MSI-H in the Chinese cohort was significantly lower in colorectal, gastric and pancreatic cancer, while significantly higher in urinary and prostate cancer. Mutations in ACVR2A (73% vs 28%, P < .01) and MMR-related genes (51.4% vs 21.3%, P < .01) were significantly higher in the Chinese population. Thus, our study suggests the fraction of MSI-H attributable to MMR inactivation mutations were lower in European than in Chinese patients, while the proportion of MSI-H due to other events may be higher.


Subject(s)
Colorectal Neoplasms , Microsatellite Instability , Neoplasms , China/epidemiology , Colorectal Neoplasms/genetics , DNA Mismatch Repair , Genomics , Humans , Microsatellite Repeats , Neoplasms/genetics
4.
Clin Lab ; 66(7)2020 Jul 01.
Article in English | MEDLINE | ID: mdl-32658416

ABSTRACT

BACKGROUND: Chronic kidney disease (CKD) is a kidney disease in which there is gradual loss of kidney function over time and end-stage renal disease (ESRD) is the final stage of CKD. Both CKD and ESRD are worldwide health problems with a high economic cost to health systems. However, the molecular mechanisms of the development of CKD and ESRD remain poorly understood. This study aimed to systematically elucidate the molecular mechanisms of the development of CKD and ESRD. METHODS: Transcriptome data of CKD and ESRD were downloaded from the NCBI-GEO database. Differentially expressed genes between cases and controls (chronic kidney disease patients vs. controls, end-stage renal disease patients vs. controls) were calculated using the empirical Bayes algorithm. Gene set enrichment analysis (GSEA) was used for analyzing the KEGG pathway difference between cases and controls. Furthermore, CKD and ESRD target genes were obtained from the Thomson Reuters Integrity database. Tissue-specific gene interaction network analysis was performed using the GIANT web server. RESULTS: There were multiple damaged pathways in ESRD but only a few pathways were disturbed in CKD. Furthermore, we identified 9 dysregulated anti-ESRD genes but no dysregulated anti-CKD genes. Network analysis revealed that the NF-kB signaling pathway was essential for ESRD. CONCLUSIONS: This study revealed several crucial anti-ESRD genes that are involved in the regulation of the NF-kB signaling pathway. This information may be helpful for the treatment of ESRD.


Subject(s)
Kidney Failure, Chronic , Renal Insufficiency, Chronic , Bayes Theorem , Humans , Kidney Failure, Chronic/diagnosis , Kidney Failure, Chronic/genetics , Renal Insufficiency, Chronic/genetics , Transcriptome
5.
Med Sci Monit ; 26: e923832, 2020 Aug 11.
Article in English | MEDLINE | ID: mdl-32779638

ABSTRACT

The latest statistics show that rates of morbidity and mortality for hepatocellular carcinoma are gradually increasing over time. Accumulating evidence indicates that circular RNAs (circRNAs) participate in the regulation of gene transcription and translation and exert a crucial role in endogenous RNA network. circRNAs are implicated in the pathogenesis of numerous tumors including hepatocellular carcinoma (HCC), gastric carcinoma and bladder cancer. Of note, the effect of circRNAs in HCC has drawn increasing public attention. Previous studies revealed that the function of circRNAs mainly consists of sponges of miRNA and RNA-binding proteins, alternative splicing of pre-mRNAs, transcriptional and translational regulators, and potential to encode proteins. In addition, recent research data indicate that the expression level of circRNAs is closely correlated with metastasis, invasion, and occurrence of HCC in patients. These findings imply that circRNAs may be useful as biomarkers for diagnosis and prediction of prognosis of HCC. In this review, we have systemically summarized current viewpoints regarding the role of circRNAs expression in HCC to provide an important reference illustrating the underlying mechanism of HCC.


Subject(s)
Carcinoma, Hepatocellular/genetics , Liver Neoplasms/genetics , RNA, Circular/physiology , Biomarkers, Tumor/metabolism , Carcinoma, Hepatocellular/pathology , Humans , Liver Neoplasms/pathology , MicroRNAs/metabolism , Neoplasm Invasiveness/genetics , Neoplasm Metastasis/genetics , Prognosis , RNA, Circular/metabolism , RNA-Binding Proteins/metabolism
6.
Med Sci Monit ; 25: 8618-8627, 2019 Nov 15.
Article in English | MEDLINE | ID: mdl-31730575

ABSTRACT

BACKGROUND Worldwide, hepatocellular carcinoma (HCC) accounts for 80-90% of all cases of primary liver cancer, and is one of the ten most common malignancies. This study used bioinformatics analysis to identify genes associated with patient outcome in stages I-IV HCC and the gene pathways that distinguished between normal liver and liver cells and HCC and human HCC cell lines. MATERIAL AND METHODS Target genes were defined as those that had marketed drugs or drugs under development targeting a specific gene and acquired from the Clarivate Analytics Integrity Database. Differential expression gene analysis, co-expression network analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, survival analysis and receiver operating characteristic (ROC) curve analysis were used to explore the similarities and differences in gene expression profiles, functional associations, and survival in stage I-IV HCC. Normal liver cells (HL-7702) and HCC cell lines (HepaRG, HepG2, SK-Hep1, and Huh7) were studied using Western blot and quantitative reverse transcription PCR (RT-qPCR). RESULTS Hierarchical gene clustering identified target genes that distinguished between HCC and normal liver tissue. For stages I-IV HCC, there were seven commonly upregulated target genes EPHB1, LTK, NTRK2, PTK7, TBK1, TIE1, and TLR3, which were mainly involved in immune and signaling transduction pathways. PTK7 was highly expressed in stage I-IV HCC and was an independent prognostic marker for reduced overall survival (OS). CONCLUSIONS Bioinformatics analysis, combined with patient survival analysis, identified PTK7 gene expression as a potential therapeutic target and prognostic biomarker for all stages of HCC.


Subject(s)
Carcinoma, Hepatocellular/genetics , Cell Adhesion Molecules/genetics , Computational Biology/methods , Receptor Protein-Tyrosine Kinases/genetics , Biomarkers, Tumor/genetics , Carcinoma, Hepatocellular/metabolism , Cell Adhesion Molecules/physiology , Cell Line, Tumor , China , Cluster Analysis , Databases, Genetic , Gene Expression Profiling/methods , Gene Expression Regulation, Neoplastic/genetics , Humans , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , Neoplasm Staging , Prognosis , Protein Interaction Maps/genetics , ROC Curve , Receptor Protein-Tyrosine Kinases/physiology , Transcriptome/genetics
7.
Biochemistry ; 56(51): 6677-6690, 2017 12 26.
Article in English | MEDLINE | ID: mdl-29190076

ABSTRACT

Choline oxidase serves as a paradigm for alcohol oxidation catalyzed by flavin-dependent enzymes. In its active site, S101 is 4 Å from the flavin C4a atom on an extended loop. Enzyme variants substituted at S101 were generated in a previous study and investigated mechanistically [Yuan, H., and Gadda, G. (2011) Biochemistry 50, 770-779]. In this study, the typical ultraviolet-visible (UV-vis) absorption spectrum of oxidized flavin was observed for the S101C enzyme in HEPES, TES, or sodium phosphate, whereas an absorption spectrum suggesting the presence of a C4a-flavin adduct with cysteine was obtained in Tris-HCl at pH 8.0. pH titrations of the UV-vis absorption spectrum of the wild-type, S101A, S101C, and H99N enzymes in the presence and absence of Tris allowed for the determination of two pKa values that define a pH range in which the C4a-S-cysteinyl flavin is stabilized. Inhibition studies and stopped-flow kinetics demonstrated that binding of protonated Tris in the active site of the S101C enzyme is required to form the C4a-S-cysteinyl flavin. Deuterium kinetic isotope effects and proton inventories of the S101C enzyme mixed in a stopped-flow spectrophotometer with Tris established a mechanism for the reversible formation of the C4a-S-cysteinyl flavin. This study provides a detailed mechanistic analysis of the reversible formation of a bicovalent C4a-S-cysteinyl-8α-N3-histidyl flavin in choline oxidase, identifying an optimal pH range and a mechanistic rationale for the stabilization of de novo C4a-S-cysteinyl-flavins. Moreover, it presents an example of an intramolecular reaction of an enzyme-bound flavin without a substrate.


Subject(s)
Alcohol Oxidoreductases/chemistry , Cysteine/chemistry , Flavins/chemistry , Crystallography, X-Ray , Hydrogen-Ion Concentration , Kinetics , Protein Conformation , Spectrophotometry, Ultraviolet
8.
J Cell Biochem ; 118(12): 4607-4616, 2017 12.
Article in English | MEDLINE | ID: mdl-28485503

ABSTRACT

This study aims to explore the effect of PKC-α gene silencing on the occurrence of ultrafiltration failure (UFF) in peritoneal dialysis (PD) rats. Forty-eight male SD rats were collected to establish 5/6 renal resection uremic and uremic PD rats models. Rats were assigned into control, sham operation, uremia, PD-2 W (peritoneal dialysis for 2 weeks), PD-4 W (peritoneal dialysis for 4 weeks), negative control (NC) (peritoneal dialysis for 4 weeks, and injected 0.1 mg/kg blank plasmid into abdominal cavity) and PKC-α siRNA (peritoneal dialysis for 4 weeks, and injected 0.1 mg/kg PKC-α siRNA into abdominal cavity) groups. CD34 staining was performed to determine microvessel density (MVD) for peritoneal tissues. The mRNA and protein expression of PKC-α in peritoneal tissue were detected by qRT-PCR and Western blot. Compared with the control group, MVD, the mRNA and protein expression of PKC-α were significantly increased in rats of the uremia, PD-2 W, PD-4 W, NC, and PKC-α siRNA groups. Compared with the uremia group, MVD, the mRNA and protein expression of PKC-α were increased, the changes observed in the PD-4 W and NC groups were better obvious than in the PD-2 W group. In comparison with the PD-4 W and NC groups, MVD, the mRNA and protein expression of PKC-α in rats were decreased in the PKC-α siRNA group. PKC-α gene has a high expression in uremic PD rats, and PKC-α gene silencing is able to increase UF while decrease MVD and glucose transport in peritoneal tissues thus reversing UFF in PD rats. J. Cell. Biochem. 118: 4607-4616, 2017. © 2017 Wiley Periodicals, Inc.


Subject(s)
Gene Silencing , Hemodiafiltration , Peritoneal Dialysis , Protein Kinase C-alpha , RNA, Small Interfering , Animals , Disease Models, Animal , Male , Protein Kinase C-alpha/antagonists & inhibitors , Protein Kinase C-alpha/genetics , Protein Kinase C-alpha/metabolism , RNA, Small Interfering/genetics , RNA, Small Interfering/pharmacology , Rats , Rats, Sprague-Dawley , Uremia/enzymology , Uremia/genetics , Uremia/pathology , Uremia/therapy
9.
Tumour Biol ; 39(5): 1010428317701648, 2017 May.
Article in English | MEDLINE | ID: mdl-28468592

ABSTRACT

Natural killer/T-cell lymphoma is a rare but aggressive neoplasm with poor prognosis. Despite previous reports that showed potential tumor suppressors, such as PRDM1 or oncogenes associated with the etiology of this malignancy, the role of long non-coding RNAs in natural killer/T-cell lymphoma pathobiology has not been addressed to date. Here, we aim to identify cancer-associated dysregulated long non-coding RNAs and signaling pathways or biological processes associated with these long non-coding RNAs in natural killer/T-cell lymphoma cases and to identify the long non-coding RNAs transcriptionally regulated by PRDM1. RNA-Seq analysis revealed 166 and 66 long non-coding RNAs to be significantly overexpressed or underexpressed, respectively, in natural killer/T-cell lymphoma cases compared with resting or activated normal natural killer cells. Novel long non-coding RNAs as well as the cancer-associated ones such as SNHG5, ZFAS1, or MIR155HG were dysregulated. Interestingly, antisense transcripts of many growth-regulating genes appeared to be transcriptionally deregulated. Expression of ZFAS1, which is upregulated in natural killer/T-cell lymphoma cases, showed association with growth-regulating pathways such as stabilization of P53, regulation of apoptosis, cell cycle, or nuclear factor-kappa B signaling in normal and neoplastic natural killer cell samples. Consistent with the tumor suppressive role of PRDM1, we identified MIR155HG and TERC to be transcriptionally downregulated by PRDM1 in two PRDM1-null NK-cell lines when it is ectopically expressed. In conclusion, this is the first study that identified long non-coding RNAs whose expression is dysregulated in natural killer/T-cell lymphoma cases. These findings suggest that ZFAS1 and other dysregulated long non-coding RNAs may be involved in natural killer/T-cell lymphoma pathobiology through regulation of cancer-related genes, and loss-of-PRDM1 expression in natural killer/T-cell lymphomas may contribute to overexpression of MIR155HG; thereby promoting tumorigenesis.


Subject(s)
Lymphoma, Extranodal NK-T-Cell/genetics , MicroRNAs/genetics , RNA, Long Noncoding/genetics , RNA/genetics , Repressor Proteins/genetics , Telomerase/genetics , Apoptosis/genetics , Carcinogenesis/genetics , Cell Line, Tumor , Female , Gene Expression Regulation, Neoplastic , Humans , Lymphoma, Extranodal NK-T-Cell/pathology , Male , MicroRNAs/biosynthesis , Natural Killer T-Cells/pathology , Positive Regulatory Domain I-Binding Factor 1 , RNA, Long Noncoding/biosynthesis , Repressor Proteins/biosynthesis , Signal Transduction , Transcriptome/genetics
10.
Arch Biochem Biophys ; 634: 76-82, 2017 11 15.
Article in English | MEDLINE | ID: mdl-29029877

ABSTRACT

Choline oxidase oxidizes choline to glycine betaine, with two flavin-mediated reactions to convert the alcohol substrate to the carbon acid product. Proton abstraction from choline or hydrated betaine aldehyde in the wild-type enzyme occurs in the mixing time of the stopped-flow spectrophotometer, thereby precluding a mechanistic investigation. Mutagenesis of S101 rendered the proton transfer reaction amenable to study. Here, we have investigated the aldehyde oxidation reaction catalyzed by the mutant enzymes using steady-state and rapid kinetics with betaine aldehyde. Stopped-flow traces for the reductive half-reaction of the S101T/V/C variants were biphasic, corresponding to the reactions of proton abstraction and hydride transfer. In contrast, the S101A enzyme yielded monophasic traces like wild-type choline oxidase. The rate constants for proton transfer in the S101T/C/V variants decreased logarithmically with increasing hydrophobicity of residue 101, indicating a behavior different from that seen previously with choline for which no correlation was determined. The rate constants for hydride transfer also showed a logarithmic decrease with increasing hydrophobicity at position 101, which was similar to previous results with choline as a substrate for the enzyme. Thus, the hydrophilic character of S101 is necessary not only for efficient hydride transfer but also for the proton abstraction reaction.


Subject(s)
Alcohol Oxidoreductases/chemistry , Betaine/analogs & derivatives , Hydrogen/chemistry , Kinetics , Metals/chemistry , Models, Chemical , Amino Acid Substitution , Betaine/chemistry , Enzyme Activation , Oxidation-Reduction , Protons , Structure-Activity Relationship
11.
Biochemistry ; 54(29): 4565-74, 2015 Jul 28.
Article in English | MEDLINE | ID: mdl-26091305

ABSTRACT

Saporin L3 from Saponaria officinalis (soapwort) leaves is a type 1 ribosome-inactivating protein. It catalyzes the hydrolysis of oligonucleotide adenylate N-ribosidic bonds to release adenine from rRNA. Depurination sites include both adenines in the GAGA tetraloop of short sarcin-ricin stem-loops and multiple adenines within eukaryotic rRNA, tRNAs, and mRNAs. Multiple Escherichia coli vector designs for saporin L3 expression were attempted but demonstrated high toxicity even during plasmid maintenance and selection in E. coli nonexpression strains. Saporin L3 is >10(3) times more efficient at RNA deadenylation on short GAGA stem-loops than saporin S6, the saporin isoform currently used in immunotoxin clinical trials. We engineered a construct for the His-tagged saporin L3 to test for expression in Pichia pastoris when it is linked to the protein export system for the yeast α-mating factor. DNA encoding saporin L3 was cloned into a pPICZαB expression vector and expressed in P. pastoris under the alcohol dehydrogenase AOX1 promoter. A fusion protein of saporin L3 containing the pre-pro-sequence of the α-mating factor, the c-myc epitope, and the His tag was excreted from the P. pastoris cells and isolated from the culture medium. Autoprocessing of the α-mating factor yielded truncated saporin L3 (amino acids 22-280), the c-myc epitope, and the His tag expressed optimally as a 32 kDa construct following methanol induction. Saporin L3 was also expressed with specific alanines and/or serines mutated to cysteine. Native and Cys mutant saporins are kinetically similar. The recombinant expression of saporin L3 and its mutants permits the production and investigation of this high-activity ribosome-inactivating protein.


Subject(s)
Plant Proteins/chemistry , Ribosome Inactivating Proteins, Type 1/chemistry , Saponaria/enzymology , Amino Acid Substitution , Base Sequence , Catalytic Domain , Hydrogen-Ion Concentration , Kinetics , Mutagenesis, Site-Directed , Pichia , Plant Proteins/biosynthesis , Plant Proteins/genetics , RNA/chemistry , RNA Cleavage , Ribosome Inactivating Proteins, Type 1/biosynthesis , Ribosome Inactivating Proteins, Type 1/genetics , Saporins , Substrate Specificity
12.
J Biol Chem ; 289(46): 32214-32229, 2014 Nov 14.
Article in English | MEDLINE | ID: mdl-25253688

ABSTRACT

The obligate intracellular human pathogen Chlamydia trachomatis is the etiological agent of blinding trachoma and sexually transmitted disease. Genomic sequencing of Chlamydia indicated this medically important bacterium was not exclusively dependent on the host cell for energy. In order for the electron transport chain to function, electron shuttling between membrane-embedded complexes requires lipid-soluble quinones (e.g. menaquionone or ubiquinone). The sources or biosynthetic pathways required to obtain these electron carriers within C. trachomatis are poorly understood. The 1.58Å crystal structure of C. trachomatis hypothetical protein CT263 presented here supports a role in quinone biosynthesis. Although CT263 lacks sequence-based functional annotation, the crystal structure of CT263 displays striking structural similarity to 5'-methylthioadenosine nucleosidase (MTAN) enzymes. Although CT263 lacks the active site-associated dimer interface found in prototypical MTANs, co-crystal structures with product (adenine) or substrate (5'-methylthioadenosine) indicate that the canonical active site residues are conserved. Enzymatic characterization of CT263 indicates that the futalosine pathway intermediate 6-amino-6-deoxyfutalosine (kcat/Km = 1.8 × 10(3) M(-1) s(-1)), but not the prototypical MTAN substrates (e.g. S-adenosylhomocysteine and 5'-methylthioadenosine), is hydrolyzed. Bioinformatic analyses of the chlamydial proteome also support the futalosine pathway toward the synthesis of menaquinone in Chlamydiaceae. This report provides the first experimental support for quinone synthesis in Chlamydia. Menaquinone synthesis provides another target for agents to combat C. trachomatis infection.


Subject(s)
Bacterial Proteins/chemistry , Chlamydia trachomatis/metabolism , Vitamin K 2/metabolism , Amino Acid Sequence , Catalytic Domain , Computational Biology , Crystallography, X-Ray , Deoxyadenosines/chemistry , Ligands , Molecular Sequence Data , Nucleosides/chemistry , Nucleotidases/chemistry , Protein Binding , Protein Multimerization , Protein Structure, Tertiary , Proteome , Recombinant Proteins/chemistry , S-Adenosylhomocysteine/chemistry , Sequence Homology, Amino Acid , Thionucleosides/chemistry
13.
J Biol Chem ; 289(34): 23764-75, 2014 Aug 22.
Article in English | MEDLINE | ID: mdl-25002579

ABSTRACT

Nitronate monooxygenase (NMO) oxidizes the mitochondrial toxin propionate 3-nitronate (P3N) to malonate semialdehyde. The enzyme has been previously characterized biochemically in fungi, but no structural information is available. Based on amino acid similarity 4,985 genes are annotated in the GenBank(TM) as NMO. Of these, 4,424 (i.e. 89%) are bacterial genes, including several Pseudomonads that have been shown to use P3N as growth substrate. Here, we have cloned and expressed the gene pa4202 of Pseudomonas aeruginosa PAO1, purified the resulting protein, and characterized it. The enzyme is active on P3N and other alkyl nitronates, but cannot oxidize nitroalkanes. P3N is the best substrate at pH 7.5 and atmospheric oxygen with k(cat)(app)/K(m)(app) of 12 × 10(6) M(-1) s(-1), k(cat)(app) of 1300 s(-1), and K(m)(app) of 110 µm. Anerobic reduction of the enzyme with P3N yields a flavosemiquinone, which is formed within 7.5 ms, consistent with this species being a catalytic intermediate. Absorption spectroscopy, mass spectrometry, and x-ray crystallography demonstrate a tightly, non-covalently bound FMN in the active site of the enzyme. Thus, PA4202 is the first NMO identified and characterized in bacteria. The x-ray crystal structure of the enzyme was solved at 1.44 Å, showing a TIM barrel-fold. Four motifs in common with the biochemically characterized NMO from Cyberlindnera saturnus are identified in the structure of bacterial NMO, defining Class I NMO, which includes bacterial, fungal, and two animal NMOs. Notably, the only other NMO from Neurospora crassa for which biochemical evidence is available lacks the four motifs, defining Class II NMO.


Subject(s)
Mixed Function Oxygenases/metabolism , Pseudomonas aeruginosa/enzymology , Amino Acid Sequence , Crystallization , Electrophoresis, Polyacrylamide Gel , Kinetics , Mixed Function Oxygenases/chemistry , Molecular Sequence Data , Protein Conformation , Sequence Homology, Amino Acid , Substrate Specificity
14.
Org Biomol Chem ; 12(44): 8828-31, 2014 Nov 28.
Article in English | MEDLINE | ID: mdl-25285783

ABSTRACT

A base-promoted [3 + 2] annulation reaction of ethyl α-chlorocyclopropaneformates with 1,3-dicarbonyl compounds is described. This method provides an efficient and straightforward route to acidic multi-substituted fulvenes with distinctive properties.

15.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(3): 780-788, 2024 Jun.
Article in Zh | MEDLINE | ID: mdl-38926967

ABSTRACT

OBJECTIVE: To investigate the role of serum adenosine deaminase (ADA) combined with globulin (GLB), creatinine (CREA), ß2-microglobulin (ß2-MG) and hemoglobin (HGB) in the initial screening of multiple myeloma (MM), in order to reduce missed diagnosis and misdiagnosis of MM. METHODS: A retrospective analysis was performed on 62 newly diagnosed multiple myeloma (NDMM) patients who were admitted to the Department of Hematology of the First Affiliated Hospital of Chengdu Medical College from April 2018 to December 2021, and 33 patients with benign hematologic diseases and 30 healthy subjects were selected as the control group. The expression of ADA in pan-cancer was analyzed using TCGA and GTEx databases. The general data and laboratory indicators of the subjects were collected, and the differences of ADA activity and other laboratory indicators in each group were compared. The relationship between serum ADA activity and clinical data of NDMM patients was analyzed. The changes of ADA activity before and after chemotherapy in NDMM patients and the differences of ADA activity in NDMM patients with different DS and ISS stages were compared. Multivariate logistic regression was used to analyze the risk factors of NDMM. The receiver operating characteristic(ROC) curve was used to evaluate the diagnostic efficacy of ADA and other laboratory indicators in MM. Bioinformatics method was used to analyze the co-expression networks and enrichment pathways of ADA. RESULTS: ADA level was significantly upregulated in tissues of 14 types of cancer in TCGA database, and ADA was highly expressed in 11 types of cancer in TCGA combined with GTEx databases. The serum levels of ADA, GLB, uric acid (UA), cystatin C (CysC) and ß2-MG in the NDMM group were significantly higher than those in benign hematologic disease group and healthy control group ( P < 0.05), while the levels of ALB and the value of albumin to globulin ratio (A∶G) in the NDMM group were significantly lower than those in the other two groups ( P < 0.001). There were significant differences in DS stage (P =0.036), ISS stage (P =0.019) and the levels of CREA (P =0.036), UA (P =0.034), ß2-MG (P =0.019) in NDMM patients with different ADA activity levels. After primary chemotherapy, ADA activity and ß2-MG concentration were decreased in NDMM patients ( P < 0.01). The comparison results of patients in different stages showed that ADA activity of patients in DS stage I+II was significantly lower than that of patients in DS stage III (P <0.05), and ADA activity of patiens in ISS stage I+II was significantly lower than that of patients in ISS stage III ( P < 0.01). Multivariate logistic regression analysis showed that increased GLB, increased ADA activity, increased CREA, increased ß2-MG and decreased HGB were independent risk factors for NDMM. The area under the curve (AUC) of ADA in the diagnosis of MM was 0.847, and the AUC of ADA combined with GLB, CREA, ß2-MG and HGB in the diagnosis of MM was 0.940. The results of co-expression network and enrichment pathway analysis showed that ADA bounded to 20 proteins and it was significantly associated with the metabolic pathways of purine, pyrimidine, nicotinate and nicotinamide. CONCLUSION: The detection of ADA activity in serum is of positive significance for the auxiliary diagnosis, therapeutic evaluation and monitoring the progress of NDMM patients. ADA combined with GLB, CREA, ß2-MG and HGB can improve the detection rate of MM, and reduce missed diagnosis and misdiagnosis to a certain extent.


Subject(s)
Adenosine Deaminase , Creatinine , Multiple Myeloma , beta 2-Microglobulin , Humans , Adenosine Deaminase/blood , Multiple Myeloma/blood , Multiple Myeloma/diagnosis , beta 2-Microglobulin/blood , Retrospective Studies , Creatinine/blood , Hemoglobins/analysis , Male , Female , Clinical Relevance
16.
J Med Chem ; 67(8): 6064-6080, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38595098

ABSTRACT

It has been shown that PRMT5 inhibition by small molecules can selectively kill cancer cells with homozygous deletion of the MTAP gene if the inhibitors can leverage the consequence of MTAP deletion, namely, accumulation of the MTAP substrate MTA. Herein, we describe the discovery of TNG908, a potent inhibitor that binds the PRMT5·MTA complex, leading to 15-fold-selective killing of MTAP-deleted (MTAP-null) cells compared to MTAPintact (MTAP WT) cells. TNG908 shows selective antitumor activity when dosed orally in mouse xenograft models, and its physicochemical properties are amenable for crossing the blood-brain barrier (BBB), supporting clinical study for the treatment of both CNS and non-CNS tumors with MTAP loss.


Subject(s)
Antineoplastic Agents , Protein-Arginine N-Methyltransferases , Protein-Arginine N-Methyltransferases/antagonists & inhibitors , Protein-Arginine N-Methyltransferases/metabolism , Humans , Animals , Mice , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/therapeutic use , Antineoplastic Agents/chemical synthesis , Drug Discovery , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/pharmacokinetics , Cell Line, Tumor , Xenograft Model Antitumor Assays , Neoplasms/drug therapy , Brain/metabolism , Structure-Activity Relationship
17.
Gene ; 860: 147233, 2023 Apr 15.
Article in English | MEDLINE | ID: mdl-36736507

ABSTRACT

This study aimed to investigate the genetic aberrations in neuroblastoma (NB) by comparing high and low-risk NB patients by whole-exome sequencing (WES) and to reveal the heterogeneity and association between somatic variants and clinical features. Seven NB patients with available clinical data were included in the study (4 in the low-risk group and 3 in the high-risk group). WES was performed and somatic variants associated with NB genes in the COSMIC database were selected through bioinformatics pipeline analysis. Variants were determined using the Integrative Genomics Viewer (IGV). Some gene variations were found in both groups, including variations in oncogene and tumor suppressor genes. In general, candidate gene variations were associated with chromatin remodeling complexes, the RAS pathway, cell proliferation, and DNA repair mechanism. Some variations in CSF1R, MSH6, PTPN11, SOX9, RET, TSC1, and DNMT1 genes were detected only in high-risk patients, while EP300, TET2, MYCN, PRDM1, and ARID2 gene variations were detected only in low-risk patients. When high-risk gene variants were compared with the cBioportal cancer genomic database, two common gene variants (ARID1A and NCOR2) were identified. However, when low-risk gene variants were compared with the cBioportal cancer genomic database, no common genes were found. GO/KEGG enrichment analysis was performed to find relevant biological processes and molecular pathways related to gene variants, which will help to decipher the molecular mechanisms of NB tumorigenesis and the phenotypic differences between high-risk and low-risk patients.


Subject(s)
Neuroblastoma , Oncogenes , Humans , Exome Sequencing , Genomics , Risk Factors , Neuroblastoma/genetics , Neuroblastoma/pathology
18.
Medicine (Baltimore) ; 102(43): e35785, 2023 Oct 27.
Article in English | MEDLINE | ID: mdl-37904360

ABSTRACT

RATIONALE: Calcium dobesilate, a vasoprotective and antioxidant agent, is gradually being used for the treatment of chronic kidney disease. Calcium dobesilate-induced hyperpyrexia is a rare clinical event, and few studies have reported it. PATIENT CONCERNS: The patient took calcium dobesilate, which caused high fever. After stopping calcium dobesilate, his body temperature returned to normal. DIAGNOSES: Based on the medical history, symptoms and signs, the patient was diagnosed with drug fever caused by calcium dobesilate. INTERVENTIONS: Calcium dobesilate was stopped, and supportive treatment was given at the same time. OUTCOMES: The present case was initially misdiagnosed as a fever caused by a bacterial infection, but treatment with the antibiotic moxifloxacin was ineffective. Based on the patient's medical history, laboratory and examination results, body temperature changes, and Naranjo Advanced Drug Response Scale, calcium dobesilate-induced hyperpyrexia was diagnosed. After discontinuation of calcium dobesilate, the patient's body temperature normalized, and no additional episode of fever was observed at follow-up. LESSON: Moreover, misdiagnosis and mistreatment of this condition can deteriorate the patient's condition. Herein, we report a case of calcium dobesilate-induced hyperpyrexia that occurred during the treatment of chronic renal insufficiency. Subsequently, a systematic analysis of the patient's diagnosis and treatment was reviewed. If unexplained high fever develops during the use of calcium dobesilate, calcium dobesilate-induced hyperpyrexia should be considered. Accordingly, calcium dobesilate should be discontinued.


Subject(s)
Calcium Dobesilate , Humans , Calcium Dobesilate/adverse effects , Hyperthermia/drug therapy , Fever/chemically induced , Fever/drug therapy
19.
Cancer Med ; 12(17): 18394-18404, 2023 09.
Article in English | MEDLINE | ID: mdl-37610374

ABSTRACT

BACKGROUND: Pathogenic germline variants (PGVs) can play a vital role in the oncogenesis process in carriers. Previous studies have recognized that PGVs contribute to early onset of tumorigenesis in certain cancer types, for example, colorectal cancer and breast cancer. However, the reported prevalence data of cancer-associated PGVs were highly inconsistent due to nonuniform patient cohorts, sequencing methods, and prominent difficulties in pathogenicity interpretation of variants. In addition to the above difficulties, due to the rarity of cases, the prevalence of cancer PGV carriers in young cancer patients affected by late-onset cancer types has not been comprehensively evaluated to date. METHODS: A total of 131 young cancer patients (1-29 years old at diagnosis) were enrolled in this study. The patients were affected by six common late-onset cancer types, namely, lung cancer, liver cancer, colorectal cancer, gastric cancer, renal cancer, and head-neck cancer. Cancer PGVs were identified and analyzed. based on NGS-based targeted sequencing followed by bioinformatic screening and strict further evaluations of variant pathogenicity. RESULTS: Twenty-three cancer PGVs in 21 patients were identified, resulting in an overall PGV prevalence of 16.0% across the six included cancer types, which was approximately double the prevalence reported in a previous pancancer study. Nine of the 23 PGVs are novel, thus expanding the cancer PGV spectrum. Seven of the 23 (30.4%) PGVs are potential therapeutic targets of olaparib, with potential implications for clinical manipulation. Additionally, a small prevalence of somatic mutations of some classic cancer hallmark genes in young patients, in contrast to all-age patients, was revealed. CONCLUSION: This study demonstrates the high prevalence of PGVs in young cancer patients with the common late-onset cancers and the potentially significant clinical implications of cancer PGVs, the findings highlight the value of PGV screening in young patients across lung cancer, liver cancer, colorectal cancer, gastric cancer, renal cancer, or head-neck cancer.


Subject(s)
Carcinoma, Renal Cell , Colorectal Neoplasms , Kidney Neoplasms , Liver Neoplasms , Stomach Neoplasms , Humans , Infant , Child, Preschool , Child , Adolescent , Young Adult , Adult , Genetic Predisposition to Disease , Germ-Line Mutation , Prevalence , Colorectal Neoplasms/epidemiology , Colorectal Neoplasms/genetics
20.
Technol Cancer Res Treat ; 22: 15330338231211138, 2023.
Article in English | MEDLINE | ID: mdl-37964559

ABSTRACT

BACKGROUND AND AIM: In neuroblastoma, anaplastic lymphoma kinase mutations have recently received attention as molecular targets for the treatment of neuroblastoma, as 6% to 10% of patients with neuroblastoma have anaplastic lymphoma kinase mutations. There are little data from the cases in Turkey. We aimed to detect anaplastic lymphoma kinase mutations and molecular heterogeneity in neuroblastoma using next-generation sequencing. This study is the first one with this many cases in Turkey. METHODS: Next-generation sequencing analysis was performed using an Illumina MiniSeq custom gene panel. Clinically important mutations were selected for the analysis. We also gathered clinical data of the patients from Turkish Pediatric Oncology Group cohorts to associate them with anaplastic lymphoma kinase mutations. This study is a retrospective cross-sectional study. We followed STROBE guideline (https://www.equator-network.org/reporting-guidelines/strobe/) on this study. RESULTS: We analyzed anaplastic lymphoma kinase in 108 patients with neuroblastoma, with a mean age of 43.76 months. Pathogenic anaplastic lymphoma kinase mutations were detected in 13 patients (12.04%). We noted that anaplastic lymphoma kinase mutations were primarily observed in intermediate- and high-risk patients (P = .028). R1275Q and F1174-related mutations were predominant; I1171T, L1226F, S1189F, V1135A, and G1125S mutations were rare. Duplicate samples did not exhibit any heterogeneity. CONCLUSIONS: We found that F1174 and R1275Q-related anaplastic lymphoma kinase mutations are the most common pathogenic mutations in neuroblastoma. Anaplastic lymphoma kinase mutation status did not show any heterogeneity, and the mutations were correlated with intermediate- or high-risk groups.


Subject(s)
Neuroblastoma , Receptor Protein-Tyrosine Kinases , Child , Child, Preschool , Humans , Anaplastic Lymphoma Kinase/genetics , Anaplastic Lymphoma Kinase/therapeutic use , Cross-Sectional Studies , Mutation , Neuroblastoma/drug therapy , Receptor Protein-Tyrosine Kinases/genetics , Receptor Protein-Tyrosine Kinases/therapeutic use , Retrospective Studies
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