Objective: To investigate the effect of ubiquitin mutation at position 331 of tumor necrosis factor receptor related factor 6 (TRAF6) on the biological characteristics of colorectal cancer cells and its mechanism. Methods: lentivirus wild type (pCDH-3×FLAG-TRAF6) and mutation (pCDH-3×FLAG-TRAF6-331mut) of TRAF6 gene expression plasmid with green fluorescent protein tag were used to infect colorectal cancer cells SW480 and HCT116, respectively. The infection was observed by fluorescence microscope, and the expressions of TRAF6 and TRAF6-331mut in cells was detected by western blot. Cell counting kit-8 (CCK-8) and plate cloning test were used to detect the proliferation ability of colorectal cancer cells in TRAF6 group and TRAF6-331mut group, cell scratch test to detect cell migration, Transwell chamber test to detect cell migration and invasion, immunoprecipitation to detect the ubiquitination of TRAF6 and TRAF6-331mut with ubiquitinof lysine binding sites K48 and K63. Western blot was used to detect the effects of TRAF6 and TRAF6-331mut over expression on the nuclear factor kappa-B (NF-κB) and mitogen activated protein kinase mitogen-activated protein kinase (MAPK)/activating protein-1(AP-1) signal pathway. Results: The successful infection of colorectal cancer cells was observed under fluorescence microscope. Western blot detection showed that TRAF6 and TRAF6-331mut were successfully expressed in colorectal cancer cells. The results of CCK-8 assay showed that on the fourth day, the absorbance values of HCT116 and SW480 cells in TRAF6-331mut group were 1.89±0.39 and 1.88±0.24 respectively, which were lower than those in TRAF6 group (2.09±0.12 and 2.17±0.45, P=0.036 and P=0.011, respectively). The results of plate colony formation assay showed that the number of clones of HCT116 and SW480 cells in TRAF6-331mut group was 120±14 and 85±14 respectively, which was lower than those in TRAF6 group (190±21 and 125±13, P=0.001 and P=0.002, respectively). The results of cell scratch test showed that after 48 hours, the percentage of wound healing distance of HCT116 and SW480 cells in TRAF6-331mut group was (31±12)% and (33±14)%, respectively, which was lower than those in TRAF6 group [(43±13)% and (43±7)%, P=0.005 and 0.009, respectively]. The results of Transwell migration assay showed that the migration numbers of HCT116 and SW480 cells in TRAF6-331mut group were significantly lower than those in TRAF6 group (P<0.001 and P<0.002, respectively). The results of Transwell invasion assay showed that the number of membrane penetration of HCT116 and SW480 cells in TRAF6-331mut group was significantly lower than those in TRAF6 group (P=0.008 and P=0.009, respectively). The results of immunoprecipitation detection showed that the ubiquitin protein of K48 chain pulled by TRAF6-331mut was lower than that of wild type TRAF6 in 293T cells co-transfected with K48 (0.57±0.19), and the ubiquitin protein of K63 chain pulled down by TRAF6-331mut in 293T cells co-transfected with K63 was lower than that of wild type TRAF6 (0.89±0.08, P<0.001). Western blot assay showed that the protein expression levels of NF-κB, p-NF-κB and p-AP-1 in TRAF6-331mut-HCT116 cells were 0.63±0.08, 0.42±0.08 and 0.60±0.07 respectively, which were lower than those in TRAF6-HCT116 cells (P=0.002, P<0.001 and P<0.001, respectively). The expression level of AP-1 protein in TRAF6-HCT116 cells was 0.89±0.06, compared with that in TRAF6-HCT116 cells. The difference was not statistically significant (P>0.05). The protein expression levels of NF-κB, p-NF-κB and p-AP-1 in TRAF6-331mut-SW480 cells were 0.50±0.06, 0.51±0.04, 0.48±0.02, respectively, which were lower than those in TRAF6-SW480 cells (all P<0.001). There was no significant difference in AP-1 protein expression between TRAF6-331mut-SW480 cells and TRAF6-SW480 cells. Conclusion: The ubiquitin site mutation of TRAF6 gene at 331 may prevent the binding of TRAF6 and ubiquitin lysine sites K48 and K63, and then affect the expressions of proteins related to downstream NF-κB and MAPK/AP-1 signal pathways, and inhibit the proliferation, migration and invasion of colorectal cancer cells.
Humans ; Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; Colorectal Neoplasms/pathology* ; Lysine/metabolism* ; NF-kappa B/metabolism* ; TNF Receptor-Associated Factor 6/metabolism* ; Transcription Factor AP-1/metabolism* ; Ubiquitin/metabolism*

OBJECTIVE: To analyze the clinical manifestation and genetic basis for four children with delayed onset Ornithine transcarbamylase deficiency (OTCD). METHODS: Clinical data of four children with OTCD admitted to the Children's Hospital of the First Affiliated Hospital of Zhengzhou University from January 2020 to April 2021 were reviewed. Peripheral blood samples of the children and their parents were collected and subjected to whole exome sequencing (WES). Bioinformatic analysis and Sanger sequencing verification were carried out to verify the candidate variants. Impact of the candidate variants on the protein structure was also predicted. RESULTS: The clinical manifestations of the four children included vomiting, convulsion and disturbance of consciousness. WES revealed that the child 1 was heterozygous for a c.421C>T (p.R141X) variant in exon 5, children 2 and 3 were hemizygous for a c.119G>A (p.R40H) variant in exon 2, and child 4 was hemizygous for a c.607T>A (p.S203T) variant in exon 5 of the OTC gene. Among these, the c.607T>A variant was unreported previously and predicted to be pathogenic (PM1+PM2_Supporting+PP3+PP4). Bioinformatic analysis has predicted that the variant may result in breakage of hydrogen bonds and alter the protein structure and function. Sanger sequencing confirmed that the variants in children 2 to 4 have derived from their mothers. CONCLUSION The pathogenic variants of the OTC gene probably underlay the delayed OTCD in 4 children. The discovery of the c.607T>A variant has enriched the mutational spectrum of the OTC gene.
Child ; Humans ; Ornithine Carbamoyltransferase Deficiency Disease/genetics* ; Exons ; Seizures ; Computational Biology ; Heterozygote

OBJECTIVES: To study new biomarkers for the early diagnosis of retinopathy of prematurity (ROP) by analyzing the differences in blood metabolites based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) and metabolomics. METHODS: Dried blood spots were collected from 21 infants with ROP (ROP group) and 21 infants without ROP (non-ROP group) who were hospitalized in the Sixth Affiliated Hospital of Sun Yat-sen University from January 2013 to December 2016. LC-MS/MS was used to measure the metabolites, and orthogonal partial least squares-discriminant analysis was used to search for differentially expressed metabolites and biomarkers. RESULTS: There was a significant difference in blood metabolic profiles between the ROP and non-ROP groups. The pattern recognition analysis, Score-plot, and weight analysis obtained 10 amino acids with a relatively large difference. Further statistical analysis showed that the ROP group had significant increases in blood levels of glutamic acid, leucine, aspartic acid, ornithine, and glycine compared with the non-ROP group (P<0.05). The receiver operating characteristic curve analysis showed that glutamic acid and ornithine had the highest value in diagnosing ROP. CONCLUSIONS Blood metabolites in preterm infants with ROP are different from those without ROP. Glutamic acid and ornithine are the metabolic markers for diagnosing ROP. LC-MS/MS combined with metabolomics analysis has a potential application value in the early identification and diagnosis of ROP.
Infant, Newborn ; Infant ; Humans ; Tandem Mass Spectrometry ; Infant, Premature ; Chromatography, Liquid ; Retinopathy of Prematurity/diagnosis* ; Glutamic Acid ; Ornithine

The occurence and development of tumors is a complicated process, which not only depends on the mutation or deletion of genes, but also is affected by epigenetic regulation. Accumulating evidences have shown that epigenetic modifications play fundamental roles in transcriptional regulation, heterochromatin formation, X chromosome inactivation, DNA damage response and tumor development. SET domain containing lysine methyltransferase 7 (SETD7) was initially identified as an important lysine methyltransferase, which methylated histone and non-histone proteins. These modifications play fundamental roles. Once this modification disorders, it can directly lead to cell abnormalities and cause many diseases. Studies have shown that SETD7 is related to the occurence and development of various tumors, but the methylation sites of SETD7 and its regulatory mechanism have not been fully elucidated. This article summarizes the research progress of the role of SETD7 on histone and non-histone methylation modification in tumors and the molecular mechanism, in order to provide new therapeutic targets for tumor pathogenesis and diagnosis.
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Humans ; Epigenesis, Genetic ; Histone-Lysine N-Methyltransferase/metabolism* ; Lysine/metabolism* ; Lung Neoplasms/genetics* ; Histones/metabolism*

The male neonate in this case study was admitted to the hospital at 15 hours of age due to respiratory distress for 15 hours and poor response for 3 hours after resuscitation from asphyxia. The neonate was highly unresponsive, with central respiratory failure and seizures. Serum ammonia was elevated (>1 000 μmol/L). Blood tandem mass spectrometry revealed a significant decrease in citrulline. Rapid familial whole genome sequencing revealed OTC gene mutations inherited from the mother. Continuous hemodialysis filtration and other treatments were given. Neurological assessment was performed by cranial magnetic resonance imaging and electroencephalogram. The neonate was diagnosed with ornithine transcarbamylase deficiency combined with brain injury. He died at 6 days of age after withdrawing care. This article focuses on the differential diagnosis of neonatal hyperammonemia and introduces the multidisciplinary management of inborn error of metabolism.
Humans ; Infant, Newborn ; Male ; Citrulline ; Electroencephalography ; Hyperammonemia ; Ornithine Carbamoyltransferase Deficiency Disease/therapy* ; Seizures

Humans ; Astrocytes ; Neocortex ; Epilepsy/therapy* ; Tosylarginine Methyl Ester

Histone lysine methyltransferases (HKMTs) deposit methyl groups onto lysine residues on histones and play important roles in regulating chromatin structure and gene expression. The structures and functions of HKMTs have been extensively investigated in recent decades, significantly advancing our understanding of the dynamic regulation of histone methylation. Here, we review the recent progress in structural studies of representative HKMTs in complex with nucleosomes (H3K4, H3K27, H3K36, H3K79, and H4K20 methyltransferases), with emphasis on the molecular mechanisms of nucleosome recognition and trans-histone crosstalk by these HKMTs. These structural studies inform HKMTs' roles in tumorigenesis and provide the foundations for developing new therapeutic approaches targeting HKMTs in cancers.
Nucleosomes ; Histones/metabolism* ; Histone-Lysine N-Methyltransferase/metabolism* ; Lysine/metabolism* ; Methyltransferases/metabolism* ; Methylation

Long noncoding RNAs (lncRNAs) play a critical role in the regulation of atherosclerosis. Here, we investigated the role of the lncRNA growth arrest-specific 5 (lncR-GAS5) in atherogenesis. We found that the enforced expression of lncR-GAS5 contributed to the development of atherosclerosis, which presented as increased plaque size and reduced collagen content. Moreover, impaired autophagy was observed, as shown by a decreased LC3II/LC3I protein ratio and an elevated P62 level in lncR-GAS5-overexpressing human aortic endothelial cells. By contrast, lncR-GAS5 knockdown promoted autophagy. Moreover, serine/arginine-rich splicing factor 10 (SRSF10) knockdown increased the LC3II/LC3I ratio and decreased the P62 level, thus enhancing the formation of autophagic vacuoles, autolysosomes, and autophagosomes. Mechanistically, lncR-GAS5 regulated the downstream splicing factor SRSF10 to impair autophagy in the endothelium, which was reversed by the knockdown of SRSF10. Further results revealed that overexpression of the lncR-GAS5-targeted gene miR-193-5p promoted autophagy and autophagic vacuole accumulation by repressing its direct target gene, SRSF10. Notably, miR-193-5p overexpression decreased plaque size and increased collagen content. Altogether, these findings demonstrate that lncR-GAS5 partially contributes to atherogenesis and plaque instability by impairing endothelial autophagy. In conclusion, lncR-GAS5 overexpression arrested endothelial autophagy through the miR-193-5p/SRSF10 signaling pathway. Thus, miR-193-5p/SRSF10 may serve as a novel treatment target for atherosclerosis.
Humans ; Atherosclerosis/genetics* ; Autophagy/genetics* ; Cell Cycle Proteins/metabolism* ; Endothelial Cells/metabolism* ; Endothelium/metabolism* ; MicroRNAs/metabolism* ; Repressor Proteins/metabolism* ; RNA Splicing Factors ; Serine-Arginine Splicing Factors/genetics* ; RNA, Long Noncoding/metabolism*

OBJECTIVE: To evaluate the efficacy and safety of glyceryl phenylbutyrate (GPB) therapy for patients with Ornithine transcarbamylase deficiency (OTCD). METHODS: Two children with OTCD were selected as the study subjects, and their clinical manifestations, blood ammonia, liver enzymes, growth and development information following the treatment with GPB were retrospectively analyzed. A literature review was also carried out by searching the PubMed database for studies on the GPB treatment for urea cycle disorders. RESULTS: With the GPB treatment, the blood ammonia and liver enzyme level in both patients have decreased to the normal range within 3 months. Motor development in child 2 has improved. No adverse reaction was noted, except for transient palmar greasy smell and loss of appetite in child 1. Analysis of the literature showed that patients had lower ammonia exposure, lower annual incidence of hyperammonemic crisis, more actual protein intake and fewer adverse events during GPB treatment. CONCLUSION GPB is safe and effective for the treatment of OTCD.
Child ; Humans ; Ornithine Carbamoyltransferase Deficiency Disease/drug therapy* ; Phenylbutyrates/therapeutic use* ; Ammonia ; Retrospective Studies

Microcystin-leucine arginine (MC-LR), a potentially carcinogenic toxin, is produced by Cyanobacteria such as Microcystis and Ananabacteria during water bloom. Increasing evidence demonstrated that MC-LR induces male reproductive toxicity, mainly by inducing germ cell apoptosis, destroying cell cytoskeleton, interfering with DNA damage repair pathway, and damaging blood-testicular barrier (BTB), which eventually lead to male sterility. Testicular Sertoli cells are the somatic cells that directly contact with spermatogenic cells in seminiferous tubules. They not only regulate immune response to maintain testicular immune homeostasis by secreting a variety of cytokines and immunosuppressive factors, but also provide the protective effects of spermatogenic cells by forming BTB. MC-LR induces inflammation and apoptosis of Sertoli cells, and destroys the integrity of the BTB, and then causes spermatogenesis dysfunction.
Male ; Humans ; Sertoli Cells ; Leucine/pharmacology* ; Arginine/pharmacology* ; Microcystins/metabolism* ; Immunity