A novel biomarker associated with EBV infection improves response prediction of immunotherapy in gastric cancer.

BACKGROUND: Novel biomarkers are required in gastric cancer (GC) treated by immunotherapy. Epstein-Barr virus (EBV) infection induces an immune-active tumor microenvironment, while its association with immunotherapy response is still controversial. Genes underlying EBV infection may determine the response heterogeneity of EBV + GC. Thus, we screened hub genes associated with EBV infection to predict the response to immunotherapy in GC. METHODS: Prognostic hub genes associated with EBV infection were screened using multi-omic data of GC. EBV + GC cells were established and confirmed by EBV-encoded small RNA in situ hybridization (EBER-ISH). Immunohistochemistry (IHC) staining of the hub genes was conducted in GC samples with EBER-ISH assay. Infiltrating immune cells were stained using immunofluorescence. RESULTS: CHAF1A was identified as a hub gene in EBV + GC, and its expression was an independent predictor of overall survival (OS). EBV infection up-regulated CHAF1A expression which also predicted EBV infection well. CHAF1A expression also predicted microsatellite instability (MSI) and a high tumor mutation burden (TMB). The combined score (CS) of CHAF1A expression with MSI or TMB further improved prognostic stratification. CHAF1A IHC score positively correlated with the infiltration of NK cells and macrophages M1. CHAF1A expression alone could predict the immunotherapy response, but its CS with EBV infection, MSI, TMB, or PD-L1 expression showed better effects and improved response stratification based on current biomarkers. CONCLUSIONS: CHAF1A could be a novel biomarker for immunotherapy of GC, with the potential to improve the efficacy of existing biomarkers.

An oncogene regulating chromatin favors response to immunotherapy: Oncogene CHAF1A and immunotherapy outcomes.

Many biological processes related to cell function and fate begin with chromatin alterations, and many factors associated with the efficacy of immune checkpoint inhibitors (ICIs) are actually downstream events of chromatin alterations, such as genome changes, neoantigen production, and immune checkpoint expression. However, the influence of genes as chromatin regulators on the efficacy of ICIs remains elusive, especially in gastric cancer (GC). In this study, thirty out of 1593 genes regulating chromatin associated with a favorable prognosis were selected for GC. CHAF1A, a well-defined oncogene, was identified as the highest linkage hub gene. High CHAF1A expression were associated with microsatellite instability (MSI), high tumor mutation burden (TMB), high tumor neoantigen burden (TNB), high expressions of PD-L1 and immune effector genes, and live infiltration of immune cells. High CHAF1A expression indicated a favorable response and prognosis in immunotherapy of several cohorts, which was independent of MSI, TMB, TNB, PD-L1 expression, immune phenotype and transcriptome scoring, and improved patient selection based on these classic biomarkers. In vivo, CHAF1A knockdown alone inhibited tumor growth but it impaired the effect of an anti-PD-1 antibody by increasing the relative tumor proliferation rate and decreasing the survival benefit, potentially through the activation of TGF-ß signaling. In conclusion, CHAF1A may be a novel biomarker for improving patient selection in immunotherapy.

Lipidomics reveals immune-related adverse events in NSCLC patients receiving immune checkpoint inhibitor.

There is a lack of reliable biomarkers to predict and identify the risk of immune-related adverse events (irAEs) in non-small cell lung cancer (NSCLC) patients undergoing immune checkpoint inhibitor (ICI) treatment. This study aims to explore potential biomarkers using lipidomics to identify and predict the risk of irAEs in NSCLC patients receiving ICI treatment. This prospective study enrolled 94 NSCLC patients with IIIB/IV stage NSCLC who underwent first-line chemotherapy in combination with ICI treatment. The prediction cohort consisted of plasma samples collected from 60 patients before ICI treatment, and the occurrence of irAE was monitored within 6 months of initiating first-line ICI therapy. The validation cohort comprised 34 patients, with plasma samples obtained from 15 patients who did not develop irAE at 6 months of ICI treatment and plasma samples collected from 19 irAE patients at the onset of irAE. Through non-targeted lipidomics and semi-targeted lipid quantification analysis, we identify 11 differentially metabolized lipids and further screened these lipids with the area under the curve (AUC) > 0.7 to predict the occurrence of irAEs in NSCLC patients following ICI treatment. The results showed that the biomarker panel consisting of 9 lipids (LPC-18:2, PC-40:6, LPC-22:6, LPC-O-18:0, PS-38:0, PC-38:6, PC-37:6, PC-36:5,LPC-17:0) exhibited a good AUC of 0.859 in the prediction and 0.940 in the validation cohort phase of the receiver operating characteristic curve; The study utilizes plasma lipidomics to develop a rapid and effective prediction model for identifying irAEs in advanced NSCLC patients who treatment with first-line chemotherapy combined with immunotherapy.

Inhibiting NF-κB-S100A11 signaling and targeting S100A11 for anticancer effects of demethylzeylasteral in human colon cancer.

Colon cancer is a common and deadly malignancy of the gastrointestinal tract. Targeting proteins that inhibit tumor proliferation could lead to innovative treatment strategies for this disease. Demethylzeylasteral, extracted naturally from Tripterygium wilfordii Hook. f., demonstrates incredible anti-colon cancer activity. However, the molecular mechanism behind this requires further investigation. This study aims to identify crucial targets and mechanisms of demethylzeylasteral in treating colon cancer, making it a promising candidate for anti-tumor therapy. Through gene knockout, overexpression techniques, and double Luciferase experiments, we confirmed that demethylzeylasteral reduces S100A11 expression in HT29 cells and in vivo tumor models to anti-colon cancer. By conducting Surface Plasmon Resonance, immunofluorescence staining, and confocal laser microscopy observations, we verified the direct interaction between demethylzeylasteral and S100A11, and explored the impact of S100A11's subcellular localization on cell proliferation. Demethylzeylasteral inhibited S100A11 expression and exhibited anti-cancer activity in both in vitro and in vivo colon cancer models. Conversely, overexpression of S100A11 hindered apoptosis induced by demethylzeylasteral. Additionally, we found that knockdown or overexpression of NF-κB respectively decreased or increased S100A11 expression, subsequently affecting cell proliferation. The dual Luciferase reporting experiment revealed that NF-κB is an upstream transcription factor regulating S100A11 expression. And Surface plasmon resonance confirmed that S100A11 can directly interact with demethylzeylasteral, this interaction limited the transport of S100A11 from the cytoplasm to nucleus, attenuation S100A11 mediated cell proliferation effect.

Intermittent fasting alleviates type 1 diabetes-induced cognitive dysfunction by improving the frontal cortical metabolic disorder.

Intermittent fasting (IF) is an ecological strategy to control various metabolic disorder symptoms, but its protective effect on type 1 diabetes (T1D)-induced cognitive dysfunction and the underlying mechanisms remain poorly defined. Herein, we examined the efficacy of IF in altering the behaviors and brain metabolome in T1D mice and investigated the potential molecular mechanisms. We demonstrated that IF remarkably improved frontal cortical-dependent memory in T1D mice and reduced the loss of neuronal cells. Metabolomics and targeted mass spectrometry assays showed that IF reprogrammed the composition of the frontal cortical metabolome in T1D mice, including activating the aspartate and glutamate pathway and reversing glycerophospholipid and sphingolipid depositions. Mechanistically, IF attenuated the levels of oxidative stress proteins, like NOX2, NOX4, 8-OHdG, and 4-HNE, and inhibited the levels of pro-apoptotic factors Bax and cleaved Caspase-3, ultimately improving the memory ability of T1D mice. In vitro studies confirmed the protective effect of the supplemented N-acetylaspartate, a pivotal metabolite involved in IF-regulated T1D-induced cognitive dysfunction, in high glucose-stimulated SH-SY5Y cells by eliminating toxic lipids accumulation, oxidative stress, and apoptosis. To conclude, the frontal cortical metabolites mediated the protective effects of IF against T1D-induced cognitive dysfunction by attenuating oxidative stress and apoptotic signaling. Thus, IF can be a potential therapeutic strategy for T1D-induced cognitive dysfunction.

Lipid metabolism reprogramming in tumor-associated macrophages and implications for therapy.

The tumormicroenvironment (TME) plays a key role in tumor progression. Tumor-associated macrophages (TAMs), which are natural immune cells abundantin the TME, are mainly divided into the anti-tumor M1 subtype and pro-tumor M2 subtype. Due to the high plasticity of TAMs, the conversion of the M1 to M2 phenotype in hypoxic and hypoglycemic TME promotes cancer progression, which is closely related to lipid metabolism. Key factors of lipid metabolism in TAMs, including peroxisome proliferator-activated receptor and lipoxygenase, promote the formation of a tumor immunosuppressive microenvironment and facilitate immune escape. In addition, tumor cells promote lipid accumulation in TAMs, causing TAMs to polarize to the M2 phenotype. Moreover, other factors of lipid metabolism, such as abhydrolase domain containing 5 and fatty acid binding protein, have both promoting and inhibiting effects on tumor cells. Therefore, further research on lipid metabolism in tumors is still required. In addition, statins, as core drugs regulating cholesterol metabolism, can inhibit lipid rafts and adhesion of tumor cells, which can sensitize them to chemotherapeutic drugs. Clinical studies on simvastatin and lovastatin in a variety of tumors are underway. This article provides a comprehensive review of the role of lipid metabolism in TAMs in tumor progression, and provides new ideas for targeting lipid metabolism in tumor therapy.

Dearomatization-Rearomatization Reaction of Metal-Polarized Aza-ortho-Quinone Methides.

Metal-polarized aza-ortho-quinone methides (aza-o-QMs) are a unique and efficient handle for azaheterocycle synthesis. Despite great achievements, the potential of these reactive intermediates has not yet been fully exploited, especially the new reaction modes. Herein, we disclosed an unprecedented dearomatization process of metal-polarized aza-o-QMs, affording transient dearomatized spiroaziridine intermediates. Based on this serendipity, we accomplished three sequential dearomatization-rearomatization reactions of benzimidazolines with aza-sulfur ylides, enabling the divergent synthesis of bis-nitrogen heterocycles with high efficiency and flexibility. Moreover, experimental and theoretical studies were performed to explain the proposed mechanisms and observed selectivity. Further cellular evaluation of the dibenzodiazepine products identified a hit compound for new antitumor drugs.

[Analysis of audiological features in infants with unilateral hearing loss].

Objective:To investigate the audiological characteristics and possible causes of unilateral hearing loss in infants and young children. Methods:105 infants from Beijing Maternal and Child Health Care Institution who failed the newborn hearing screening and were referred to the Children's Hearing Diagnosis Center of PLA General Hospital for hearing diagnosis. They were diagnosed with unilateral hearing loss and underwent clinical data collection. A full set of audiological examinations included ABR, 40 Hz auditory event related potential, ASSR, DPOAE, tympanometry. Results:①In initial diagnosis, 45 cases（42.86%） had mild hearing loss, 19 cases（18.10%） had moderate hearing loss, 14 cases（13.33%） had severe hearing loss, and 27 cases（25.71%） had severe hearing loss; Among them, 65 cases（61.90%） were conductive hearing loss or mixed hearing loss, and 40 cases（38.10%） were sensorineural hearing loss. ②83 of 105 cases had follow-up visits: 24 cases were normal, 15 cases with mild hearing loss, 4 cases with moderate hearing loss, 12 cases with severe hearing loss, and 26 cases with extremely severe hearing loss, 2 cases of hearing loss in both ears. ③From the initial diagnosis to the follow-up diagnosis, the change of mild hearing loss was the largest, followed by moderate hearing loss, severe and extremely severe hearing loss basically did not change; the number of mild and severe conductive hearing loss which recovered to normal hearing was most, the number of sensorineural hearing loss changed little. Conclusion:The infants who failed the newborn hearing screening and were diagnosed with unilateral hearing loss were mainly mild to moderate conductive hearing loss and severe to extremely severe sensorineural hearing loss. The hearing of children with hearing loss gradually improved, and severe and extremely severe sensorineural hearing loss remained unchanged.

[Application of behavioral audiometry in subjective hearing assessment of children].

Objective:To explore the value and influencing factors of behavioral audiometry in subjective hearing assessment of children. Methods:The results of behavioral audiometry（visual reinforcement audiometry or play audiometry） of 1944 children（3888 ears） in the outpatient department from January 2012 to December 2015 were retrospectively analyzed. The subjective performance（" good ", "moderate", "poor", " unfinished "） was compared according to age and hearing level. SPSS 27.0 software was used for statistical analysis. Results:The subjective performance of children was "good" in 2791 ears（71.8%）, "moderate" in 411 ears（10.6%）, "poor" in 309 ears（7.9%） and " unfinished " in 377 ears（9.7%）. In visual reinforcement audiometry, the proportion of children who subjectively performed as "good" gradually increased with age, reaching the peak at 2 years old, and decreased with age after 2 years old. In play audiometry, the proportion of children who subjectively performed as "good" gradually increased with age, peaking at 4-5 years of age. The children who did not finish the test were mainly 1-3 years old. The reasons included uncooperation for 148 ears, crying for 95 ears, refusing to wear headphones for 57 ears, fatigue for 42 ears, lack of interest for 20 ears, not understanding for 14 ears, and distraction for 1 ear. Conclusion:Behavioral audiometry was helpful to assess children's subjective hearing, and children's subjective performance was good. In clinical work, more novel and attractive test materials and methods should be adopted or developed according to the physical and mental characteristics of young children.

[The follow-up study on patients of children with auditory neuropathy].

Objective:To analyse the audiological characteristics of patients of children with auditory neuropathy（AN） for gaining a better understanding of the audiological characteristics prognosis of patients with AN. Methods:58 patients（108 ears） of children with AN were enrolled, all of whom had received further consultation within 10 years after the first consultation. Behavioral audiometry test, tympanogram test, distortion product otoacoustic emission（DPOAE）, auditory brainstem response（ABR）, cochlear microphonics（CM）, auditory steady-state response（ASSR） were performed on these patients. Results:①There were no significant changes in behavioral audiometry threshold between first and further consultation（P>0.05）；②Tympanograms were mostly of type A or As； ③The patients had worse DPOAE results in the further consultation, while the elicitation rate of other frequencies were higher except for the lower elicitation rate of 750 Hz and 1000 Hz；④There were 7 ears that had present ABR and CM in the first consultation, while three ears had present ABR and CM in the further consultation；⑤Except for 500 Hz, other frequency thresholds of ASSR in the further consultation were statistically significant compared with those in the first consultation（P<0.01）；⑥The threshold of behavioral audiometry at 4000 Hz was higher than that of ASSR, and there was no obvious correlation between the other frequencies（P>0.05）. Conclusion:There is a tendency of hearing deterioration in patients of children with AN. Patients with no DPOAE elicitation and no ABR elicitation or serious abnormalities need CM test to avoid misdiagnosis. The hearing status and speech communication ability of patients should be continuously monitored. Parents should pay attention to the changes in the behavioral ability of the children in daily life and make regular subsequent visits.

m6A methylation modification and immune cell infiltration: implications for targeting the catalytic subunit m6A-METTL complex in gastrointestinal cancer immunotherapy.

N6-methyladenosine (m6A) methylation modification is a ubiquitous RNA modification involved in the regulation of various cellular processes, including regulation of RNA stability, metabolism, splicing and translation. Gastrointestinal (GI) cancers are some of the world's most common and fatal cancers. Emerging evidence has shown that m6A modification is dynamically regulated by a complex network of enzymes and that the catalytic subunit m6A-METTL complex (MAC)-METTL3/14, a core component of m6A methyltransferases, participates in the development and progression of GI cancers. Furthermore, it has been shown that METTL3/14 modulates immune cell infiltration in an m6A-dependent manner in TIME (Tumor immune microenvironment), thereby altering the response of cancer cells to ICIs (Immune checkpoint inhibitors). Immunotherapy has emerged as a promising approach for treating GI cancers. Moreover, targeting the expression of METTL3/14 and its downstream genes may improve patient response to immunotherapy. Therefore, understanding the role of MAC in the pathogenesis of GI cancers and its impact on immune cell infiltration may provide new insights into the development of effective therapeutic strategies for GI cancers.

ACSL3 and ACSL4, Distinct Roles in Ferroptosis and Cancers.

The long-chain fatty acyl CoA synthetase (ACSLs) family of enzymes contributes significantly to lipid metabolism and produces acyl-coenzyme A by catalyzing fatty acid oxidation. The dysregulation of ACSL3 and ACSL4, which belong to the five isoforms of ACSLs, plays a key role in cancer initiation, development, metastasis, and tumor immunity and may provide several possible therapeutic strategies. Moreover, ACSL3 and ACSL4 are crucial for ferroptosis, a non-apoptotic cell death triggered by the accumulation of membrane lipid peroxides due to iron overload. Here, we present a summary of the current knowledge on ACSL3 and ACSL4 and their functions in various cancers. Research on the molecular mechanisms involved in the regulation of ferroptosis is critical to developing targeted therapies for cancer.

De Novo Construction of Chiral Aminoindolines by Cu-Catalyzed Asymmetric Cyclization and Subsequent Discovery of an Unexpected Sulfonyl Migration.

Searching for efficient strategies to access structurally novel aminoindolines is of great significance for drug discovery. However, catalytic asymmetric de novo construction of aminoindoline scaffolds with functionality primed for diversification still remains elusive. Here, we report a Cu-catalyzed asymmetric cyclization of ethynyl benzoxazinones with amines, producing chiral 3-aminoindolines in good yield and with high enantioselectivity (up to 97% yield and 98:2 er). Moreover, a radical-mediated sulfonyl migration of these products was unexpectedly found, further affording new chiral 3-aminoindolines bearing alkenyl sulfonyl groups with retained enantiopurity (up to 84% yield and 98:2 er). Bioactivity evaluations indicate that these 3-aminoindolines show notable antitumor activities and chirality is proven to have a significant impact on their antitumor activity.

A Genomic Signature Reflecting Fibroblast Infiltration Into Gastric Cancer Is Associated With Prognosis and Treatment Outcomes of Immune Checkpoint Inhibitors.

Background: The immunotherapy efficacy in gastric cancer (GC) is limited. Cancer-associated fibroblasts (CAFs) induce primary resistance to immunotherapy. However, CAF infiltration in tumors is difficult to evaluate due to the lack of validated and standardized quantified methods. This study aimed to investigate the impact of infiltrating CAFs alternatively using fibroblast-associated mutation scoring (FAMscore). Methods: In a GC cohort from Affiliated Hospital of Jiangsu University (AHJU), whole exon sequencing of genomic mutations, whole transcriptome sequencing of mRNA expression profiles, and immunofluorescence staining of tumor-infiltrating immune cells were performed. GC data from The Cancer Genome Atlas were used to identify genetic mutations which were associated with overall survival (OS) and impacted infiltrating CAF abundance determined by transcriptome-based estimation. FAMscore was then constructed through a least absolute shrinkage and selection operator Cox regression model and further validated in AHJU. The predictive role of FAMscore for immunotherapy outcomes was tested in 1 GC, one melanoma, and two non-small-cell lung cancer (NSCLC-1 and -2) cohorts wherein participants were treated by immune checkpoint inhibitors. Results: FAMscore was calculated based on a mutation signature consisting of 16 genes. In both TCGA and AHJU, a high FAMscore was an independent predictor for poor OS of GC patients. FAMscore was associated with immune-associated genome biomarkers, immune cell infiltration, and signaling pathways of abnormal immunity. Importantly, patients with high FAMscore presented inferiority in the objective response rate of immunotherapy compared to those with low FAMscore, with 14.6% vs. 66.7% (p<0.001) in GC, 19.6% vs. 68.2% (p<0.001) in NSCLC-1, 23.1% vs 75% (p = 0.007) in NSCLC-2, and 40.9% vs 75% (p = 0.037) in melanoma. For available survival data, a high FAMscore was also an independent predictor of poor progression-free survival in NSCLC-1 (HR = 2.55, 95% CI: 1.16-5.62, p = 0.02) and NSCLC-2 (HR = 5.0, 95% CI: 1.13-22.19, p = 0.034) and poor OS in melanoma (HR = 3.48, 95% CI: 1.27-9.55, p = 0.015). Conclusions: Alternative evaluation of CAF infiltration in GC by determining the FAMscore could independently predict prognosis and immunotherapy outcomes. The FAMscore may be used to optimize patient selection for immunotherapy.

Austenite Stability and Deformation Behavior in Medium Mn Steel Processed by Cyclic Quenching ART Heat Treatment.

This study investigated the austenite stability and deformation behavior of cyclic quenching-austenite reverse transformation processed Fe-0.25C-3.98Mn-1.22Al-0.20Si-0.19Mo-0.03Nb medium Mn steel. A number of findings were obtained. Most importantly, the extent of the TRIP effect was mainly determined by an appropriately retained austenite stability rather than its content. Simultaneously, chemical elements were the key factors affecting austenite stability, of which Mn had the greatest impact, while the difference of retained austenite grain size and Mn content resulted in different degrees of retained austenite stability. Additionally, there were still large amounts of strip and granular-retained austenite shown in the microstructure of the CQ3-ART sample after tensile fracture, revealing that the excessively stable, retained austenite inhibited the generation of an extensive TRIP effect.

Strengthening Mechanism and Carbide Precipitation Behavior of Nb-Mo Microalloy Medium Mn Steel.

This study investigates the strengthening mechanism and carbide precipitation behavior of medium Mn steel with Nb-Mo microalloy after cyclic quenching and austenite reverse transformation treatment. The results show that the Nb/Mo element not only precipitates (Nb,Mo)C in the grains, hindering the movement of dislocations and increases the strength, but also segregates at the austenite/ferrite grain boundary, thus delaying the transformation from austenite to ferrite. In addition, a large amount of nano-scale cementite is retained after cyclic quenching and austenite reverse transformation, which has a positive effect on the proportion of retained austenite in medium Mn steel. Moreover, the carbides with small size and low Mn content are dissolved, and the decomposed C and Mn content are beneficial to the nucleation of austenite during the intercritical annealing process at a temperature of 690 °C.

Glutamine Metabolism Scoring Predicts Prognosis and Therapeutic Resistance in Hepatocellular Carcinoma.

Glutamine metabolism (GM) plays a critical role in hepatocellular carcinoma (HCC); however, a comprehensive methodology to quantify GM activity is still lacking. We developed a transcriptome-based GMScore to evaluate GM activity and investigated the association of GMScore with prognosis and therapeutic resistance. Two independent HCC cohorts with transcriptome data were selected from The Cancer Genome Atlas (TCGA, n = 365) and the International Cancer Genome Consortium (ICGC, n = 231). The expression of 41 GM-associated genes were used to construct and validate GMScore. Several genomic or transcriptomic biomarkers were also estimated. Tumor response to immune checkpoint inhibitors (ICIs) was predicted using the tumor immune dysfunction and exclusion algorithm. GMScore was closely correlated with patient characteristics, including stage, histology grade, alpha-fetoprotein level, and vascular invasion. High GMScore was an independent risk factor for overall survival (OS) in both cohorts (HR = 4.2 and 3.91, both p < 0.001), superior to clinical indices and other biomarkers. High GMScore presented transcriptome features to indicate cell growth advantages and genetic stability, which was associated with poor OS of patients who received transcatheter arterial chemoembolization (TACE). High GMScore was also related to high expression of immune checkpoint genes, increased infiltration of regulatory T cells, and decreased infiltration of M1 macrophages. More importantly, high GMScore indicated poor predicted responses to ICIs, which could be verified in an ICI-treated melanoma cohort. In conclusion, GMScore is a strong prognostic index that may be integrated into existing clinical algorithms. A high GMScore may indicate resistance to TACE and ICIs based on its transcriptome and immune features. Validations using other HCC cohorts, especially ICI-treated HCC cohorts, are necessary.

[Identification of a novel mutation of CEACAM16 gene in a Chinese family with autosomal dominant nonsyndromic hearing loss].

Objective:To explore the genetic cause of a Chinese autosomal dominant nonsyndromic hearing loss family and investigate the clinical features and molecular genetic characteristics of this family. Method:Detailed medical history and systematic audiology tests were carried out in the family members, and they were subjected to comprehensive genetic analyses using massively parallel sequencing, which targeted 139 known deafness genes and 6 mitochondrial DNA mutations associated with hearing loss. Result:This family's hearing loss was consistent with autosomal dominant nonsyndromic hearing loss. The affected family members appeared to have developed a high-frequency hearing loss with the onset of twenties. We identified a heterozygous missense mutation, c.418A>G/p. Thr140Ala in the CEACAM16 gene, segregating with the deafness in this family. Conclusion:In this study, we identified a new mutation of CEACAM16 gene, which was the second mutation identified in Chinese hearing loss population. It has enriched the mutation spectrum of this gene.

[Analysis of TSC gene mutations in five patients with tuberous sclerosis complex].

OBJECTIVE: To identify pathogenic mutations of TSC1 and TSC2 genes in two familial and one sporadic cases with tuberous sclerosis complex (TSC). METHODS: For five patients and their family members, potential mutations of the TSC1 and TSC2 genes were detected by direct sequencing. RESULTS: For one family, a novel missense mutation c.1964C>T (p.S655F) was detected in the exon 19 of the TSC2 gene. For the sporadic patient, a repeat substitution with deletion mutation c.5238-5255delCATCAAGCGGCTCCGCCA (p.His1746GlnfsX56) was detected in the exon 40 of the TSC2 gene, which led to a stop codon TGA after the 56th amino acids. No mutation was found in another family. CONCLUSION: The missense mutation c.1964C>T(P.S655F) and the substitution with deletion mutation 5238-5255delCATCAAGCGGCTCCGCCA(p.His1746GlnfsX56) of the TSC2 gene probably underlie the disease in the first family and the sporadic case.

[Two novel mutations of the ADAR1 gene associated with dyschromatosis symmetrica hereditaria].

OBJECTIVE: To identify potential mutation of the ADAR1 gene in a Chinese family and a sporadic case affected with dyschromatosis symmetrica hereditaria(DSH). METHODS: Clinical data and peripheral blood samples from the pedigree and the sporadic patient were collected. Following extraction of genomic DNA, all 15 exons and exon-intron flanking sequences of the ADAR1 gene were amplified by polymerase chain reaction and subjected to direct sequencing. RESULTS: A novel frame-shift mutation c.2638delG (p.Asp880ThrfsX15) from the patients of the pedigree was detected in exon 8 of the ADAR1 gene. And a novel nonsense mutation c.2867C>A (p.Ser956X) was detected in exon 10 of the ADAR1 gene from the sporadic case. Neither mutation was identified among the unaffected family members nor 100 unrelated healthy controls. CONCLUSION: The frame-shift mutation c.2638delG (p.Asp880ThrfsX15) and the nonsense mutation c.2867C>A (p.Ser956X) in the ADAR1 gene probably underlie the DSH in our patients.