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Background: Disinfectants are important in the food industry to prevent the transmission of pathogens. Excessive use of disinfectants may increase the probability of bacteria experiencing long-term exposure and consequently resistance and cross-resistance to antibiotics. This study aims to investigate the cross-resistance of multidrug-resistant, drug-resistant, and drug-susceptible isolates of Salmonella enterica serovar Typhimurium (S. Typhimurium) with different sequence types (STs) to a group of antibiotics after exposure to different food-grade disinfectants. Methods: A panel of 27 S. Typhimurium strains with different antibiograms and STs were exposed to increasing concentrations of five food-grade disinfectants, including hydrogen peroxide (H2O2), benzalkonium chloride (BAC), chlorine dioxide (ClO2), sodium hypochlorite (NaClO), and ethanol. Recovered evolved strains were analyzed using genomic tools and phenotypic tests. Genetic mutations were screened using breseq pipeline and changes in resistance to antibiotics and to the same disinfectant were determined. The relative fitness of evolved strains was also determined. Results: Following exposure to disinfectants, 22 out of 135 evolved strains increased their resistance to antibiotics from a group of 14 clinically important antibiotics. The results also showed that 9 out of 135 evolved strains had decreased resistance to some antibiotics. Genetic mutations were found in evolved strains. A total of 77.78% of ST34, 58.33% of ST19, and 66.67% of the other STs strains exhibited changes in antibiotic resistance. BAC was the disinfectant that induced the highest number of strains to cross-resistance to antibiotics. Besides, H2O2 induced the highest number of strains with decreased resistance to antibiotics. Conclusions: These findings provide a basis for understanding the effect of disinfectants on the antibiotic resistance of S. Typhimurium. This work highlights the link between long-term exposure to disinfectants and the evolution of resistance to antibiotics and provides evidence to promote the regulated use of disinfectants. [ABSTRACT FROM AUTHOR]

Background: This study aimed to comprehensively evaluate the efficacy and toxicity of afatinib in patients with sarcopenia, an important prognostic factor for treatment efficacy and toxicity in patients with cancer. Methods: The clinical features of patients with advanced NSCLC treated with frontline afatinib between 2014 and 2018 at a medical center in Taiwan were retrospectively reviewed. Sarcopenia was evaluated based on the total cross‐sectional area of skeletal muscles assessed by computed tomography (CT) imaging at the L3 level. Baseline characteristics, response rates, survival rates, and adverse events (AEs) were compared between sarcopenic and nonsarcopenic patients. Results: A total of 176 patients evaluated for sarcopenia by CT and treated with afatinib were enrolled in the current study. Sarcopenia was significantly associated with good performance status, low body mass index (BMI), low body surface area (BSA), and low total mass area (TMA). Sarcopenia did not influence the response rate (69.2% vs. 72.0%, p = 0.299), progression‐free survival (median 15.9 vs. 14.9 months, p = 0.791), or overall survival (median 26.5 vs. 27.2 months, p = 0.441). However, BSA ≤ 1.7 and the 40 mg afatinib dose were associated with dose reduction. TMA was the only independent factor for afatinib discontinuation due to AEs. Conclusion: Sarcopenia was not associated with treatment efficacy or toxicity among patients with NSCLC harboring common mutations treated with afatinib, indicating sarcopenic patients should not be excluded from afatinib treatment. Other factors, such as BSA and TMA, were associated with dose reduction and afatinib discontinuation, respectively, which may require additional evaluations in future studies. [ABSTRACT FROM AUTHOR]

Background: Programmed death‐ligand 1 (PD‐L1) expression is associated with clinical outcomes of epidermal growth factor receptor (EGFR) mutant lung adenocarcinoma (ADC) treated with tyrosine kinase inhibitors (TKIs). However, whether PD‐L1 expression plays a role in anaplastic lymphoma kinase (ALK)‐positive lung ADC is unknown. We aimed to evaluate the impact of PD‐L1 in patients with ALK‐positive lung ADC receiving crizotinib. Materials and Methods: PD‐L1 expression was identified by immunohistochemistry (IHC). Reverse transcriptase‐polymerase chain reaction was used for ALK variant detection, and immunofluorescence‐based multiplex staining was applied for exploring immune cells in tumor microenvironments. Results: A total of 78 patients with ALK‐positive advanced ADC were enrolled in our study, of whom 52 received crizotinib. Compared with EGFR/ALK wild‐type tumors, PD‐L1 expression was lower in ALK‐positive ADC. ALK fusion variants were identified in 32 patients, and those with variant 3 and 5 (short variants) had higher PD‐L1 expression than those with other variants. The crizotinib objective response rate (ORR) and progression‐free survival (PFS) was better in tumors with negative PD‐L1 expression (ORR/PFS in PD‐L1 0% vs. 1%–49% vs. 50%–100%: 60.7%/11.8 months vs. 38.5%/6.5 months vs. 36.4%/4.0 months, p =.007/.022). The multivariate Cox proportional hazards model revealed that PD‐L1 0% (vs. ≥1%) was an independent factor for longer PFS (adjusted hazard ratio 0.322, 95% confidence interval 0.160–0.650, p =.002). Multiplex IHC in three cases showed a varied extent of immune cell infiltrations in tumors with different PD‐L1 expression. Conclusion: Positive PD‐L1 expression was associated with unfavorable clinical outcomes in patients with ALK‐positive lung ADC receiving crizotinib. Implications for Practice: Not all lung adenocarcinoma with sensitizing driver mutations experienced durable responses to small‐molecule tyrosine kinase inhibitors (TKIs). Similar to the negative impact of programmed death‐ligand 1 (PD‐L1) in epidermal growth factor receptor mutant tumors treated with TKIs, this study demonstrated that positive PD‐L1 expression was also associated with worse response rate and shorter progression‐free survival of anaplastic lymphoma kinase (ALK)‐positive adenocarcinoma treated with crizotinib. Among different ALK fusion partners, tumors with short variants (V3 and V5) had higher PD‐L1 compared with long variants (V1, V2, and V6). Testing PD‐L1 before initiating crizotinib for ALK‐positive lung cancer could be a simple method to provide important prognostic information. This article focuses on the effect of PD‐L1 on ALK‐positive lung adenocarcinoma and examines the association of pretreatment tumor PD‐L1 and clinical outcomes of patients receiving the first approved ALK inhibitor, crizotinib. [ABSTRACT FROM AUTHOR]

Genetic factors are an important cause of idiopathic sensorineural hearing impairment (SNHI). From the epidemiological perspective, mutations of three deafness genes: GJB2, SLC26A4, and MT-RNR1, are much more prevalent than those of other genes worldwide. However, mutation spectra of common deafness genes differ remarkably across different populations. Here, we performed comprehensive genetic examination and haplotype analyses in 188 unrelated Mongolian families with idiopathic SNHI, and compared their mutation spectra and haplotypes to those of other European and Asian cohorts. We confirmed genetic diagnoses in 18 (9.6%) of the 188 families, including 13 with bi-allelic GJB2 mutations, three with bi-allelic SLC26A4 mutations, and two with homoplasmic MT-RNR1 m.1555A>G mutation. Moreover, mono-allelic mutations were identified in 17 families (9.0%), including 14 with mono-allelic GJB2 mutations and three with mono-allelic SLC26A4 mutations. Interestingly, three GJB2 mutations prevalent in other populations, including c.35delG in Caucasians, c.235delC in East Asians, and c.-23+1G>A in Southwest and South Asians, were simultaneously detected in Mongolian patients. Haplotype analyses further confirmed founder effects for each of the three mutations, indicating that each mutation derived from its ancestral origin independently. By demonstrating the unique spectra of deafness-associated mutations, our findings may have important clinical and scientific implications for refining the molecular diagnostics of SNHI in Mongolian patients, and for elucidating the genetic relationships among Eurasian populations. [ABSTRACT FROM AUTHOR]

Rapid metastasis contributes significantly to the high mortality rates in lung adenocarcinoma. The present study reports a rare case of primary lung adenocarcinoma with concomitant gastric, duodenal, bone, and mediastinal lymph node metastases. A large gene panel based on the next-generation sequencing was used to detect gene mutations in different metastatic sites and blood. The results showed that the gene mutation spectrums among different metastatic foci were roughly similar. The mutation abundance was highest in mediastinal lymph nodes. Unique mutation sites were detected only in mediastinal lymph nodes, bone, and gastric metastatic foci. Despite partial heterogeneity, there are currently no applicable targeted drugs to adopt. In addition, tumor mutation burden (TMB) showed that blood, gastric, bone, and mediastinal lymph node metastases were all TMB-High, while the duodenal metastasis was TMB-Low. This study is the first to report a rare case of newly diagnosed lung adenocarcinoma with concomitant gastrointestinal metastases and to perform mutation analyses on all metastatic foci. Large sample sizes with similar cases are required to gain deeper insights. [ABSTRACT FROM AUTHOR]

Objectives: To investigate speech and language outcomes in children with cochlear implants (CIs) who had mutations in common deafness genes and to compare their performances with those without mutations. Study Design: Prospective study. Methods: Patients who received CIs before 18 years of age and had used CIs for more than 3 years were enrolled in this study. All patients underwent mutation screening of three common deafness genes: GJB2, SLC26A4 and the mitochondrial 12S rRNA gene. The outcomes with CIs were assessed at post-implant years 3 and 5 using the Categories of Auditory Performance (CAP) scale, Speech Intelligibility Rating (SIR) scale, speech perception tests and language skill tests. Results: Forty-eight patients were found to have confirmative mutations in GJB2 or SLC26A4, and 123 without detected mutations were ascertained for comparison. Among children who received CIs before 3.5 years of age, patients with GJB2 or SLC26A4 mutations showed significantly higher CAP/SIR scores than those without mutations at post-implant year 3 (p = 0.001 for CAP; p = 0.004 for SIR) and year 5 (p = 0.035 for CAP; p = 0.038 for SIR). By contrast, among children who received CIs after age 3.5, no significant differences were noted in post-implant outcomes between patients with and without mutations (all p > 0.05). Conclusion: GJB2 and SLC26A4 mutations are associated with good post-implant outcomes. However, their effects on CI outcomes may be modulated by the age at implantation: the association between mutations and CI outcomes is observed in young recipients who received CIs before age 3.5 years but not in older recipients. [ABSTRACT FROM AUTHOR]

Background: A novel link between oncogenic KRAS signalling and WT1 was recently identified. We sought to investigate the role of WT1 and KRAS in proliferation and apoptosis. Methods: KRAS mutations and WT1 (cMyc) expression were detected using Sanger sequencing and real-time PCR in 77 patients with non-small cell lung cancer (NSCLC). Overexpression and knockdown of WT1 were generated with plasmid and siRNA via transient transfection technology in H1299 and H1568 cells. MTT assay for detection of cell proliferation, and TUNEL assay and proteomic profiler assay for apoptosis evaluation were carried out. Dual luciferase reporter assay and ChIP-PCR were performed to validate the effect of WT1 on the cMyc promoter. Results: KRAS mutations showed a negative impact on overall survival (OS). High expressions of WT1 and cMyc were associated with poor OS in KRAS mutant subgroup. The potential mechanisms that WT1 promotes proliferation and impedes apoptosis through affecting multiple apoptosis-related regulators in KRAS mutant NSCLC cells were identified. WT1 could activate cMyc promoter directly in KRAS mutant cells. Conclusion: The results suggest that WT1 and c-MYC expression is important for survival in KRAS mutant tumors as opposed to KRAS wild-type tumors. For treatment of KRAS mutant NSCLC, targeting WT1 and cMyc may provide alternative therapeutic strategies. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Recent studies have confirmed the utility of massively parallel sequencing (MPS) in addressing genetically heterogeneous hereditary hearing impairment. By applying a MPS diagnostic panel targeting 129 known deafness genes, we identified a novel frameshift GATA3 mutation, c.149delT (p.Phe51LeufsX144), in a hearing-impaired family compatible with autosomal dominant inheritance. The GATA3 haploinsufficiency is thought to be associated with the hypoparathyroidism, sensorineural deafness, and renal dysplasia (HDR) syndrome. The pathogenicity of GATA3 c.149delT was supported by its absence in the 5400 NHLBI exomes, 1000 Genomes, and the 100 normal hearing controls of the present study; the co-segregation of c.149delT heterozygosity with hearing impairment in 9 affected members of the family; as well as the nonsense-mediated mRNA decay of the mutant allele in in vitro functional studies. The phenotypes in this family appeared relatively mild, as most affected members presented no signs of hypoparathyroidism or renal abnormalities, including the proband. To our knowledge, this is the first report of genetic diagnosis of HDR syndrome before the clinical diagnosis. Genetic examination for multiple deafness genes with MPS might be helpful in identifying certain types of syndromic hearing loss such as HDR syndrome, contributing to earlier diagnosis and treatment of the affected individuals. [ABSTRACT FROM AUTHOR]

Aims Me CP2 gene mutations are associated with Rett syndrome and X-linked mental retardation ( XLMR), diseases characterized by abnormal brain development and function. Recently, we created a novel Me CP2 A140V mutation mouse model that exhibited abnormalities of cell packing density and dendritic branching consistent with that seen in Rett syndrome patients as well as other Me CP2 mutant mouse models. Therefore, we hypothesized that some deficits of neuronal and synaptic functions might also be present in the A140V mutant model. Methods Here, we tested our hypothesis in hippocampal slices using electrophysiological recordings. Results We found that in young A140V mutant mice (3- to 4-week-old), hippocampal CA1 pyramidal neurons exhibited more positive resting membrane potential, increased action potential ( AP) firing frequency induced by injection of depolarizing current, wider AP duration, and smaller after hyperpolarization potential compared to neurons prepared from age-matched wild-type mice, suggesting a neuronal hyperexcitation. At the synaptic level, A140V mutant neurons exhibited a reduced frequency of spontaneous IPSCs (inhibitory postsynaptic potentials) and an enhanced probability of evoked glutamate release, both suggesting neuronal hyperexcitation. However, hippocampal CA1 long-term potentiation was not significantly different between A140V and WT mice. In adult mice (11- to 13-month-old), in addition to neuronal hyperexcitation, we also found significant deficits of both short-term and long-term potentiation of CA3- CA1 synapses in A140V mice compared to WT mice. Conclusions These results clearly illustrate the age-dependent abnormalities of neuronal and synaptic function in the Me CP2 A140V mutant mouse model, which provides new insights into the understanding of the pathogenesis of Rett syndrome. [ABSTRACT FROM AUTHOR]

Mutations in the SLC26A4 gene are a common cause of human hereditary hearing impairment worldwide. Previous studies have demonstrated that different SLC26A4 mutations have different pathogenetic mechanisms. By using a genotype-driven approach, we established a knock-in mouse model (i.e., Slc26a4tm2Dontuh/tm2Dontuh mice) homozygous for the common p.H723R mutation in the East Asian population. To verify the pathogenicity of the p.H723R allele in mice, we further generated mice with compound heterozygous mutations (i.e., Slc26a4tm1Dontuh/tm2Dontuh) by intercrossing Slc26a4+/tm2Dontuh mice with Slc26a4tm1Dontuh/tm1Dontuh mice, which segregated the c.919-2A>G mutation with an abolished Slc26a4 function. Mice were then subjected to audiologic assessments, a battery of vestibular evaluations, inner ear morphological studies, and noise exposure experiments. The results were unexpected; both Slc26a4tm2Dontuh/tm2Dontuh and Slc26a4tm1Dontuh/tm2Dontuh mice showed normal audiovestibular phenotypes and inner ear morphology, and they did not show significantly higher shifts in hearing thresholds after noise exposure than the wild-type mice. The results indicated not only the p.H723R allele was non-pathogenic in mice, but also a single p.H723R allele was sufficient to maintain normal inner ear physiology in heterozygous compound mice. There might be discrepancies in the pathogenicity of specific SLC26A4 mutations in humans and mice; therefore, precautions should be taken when extrapolating the results of animal studies to humans. [ABSTRACT FROM AUTHOR]

Germline mutations in genes that cause hereditary syndromes are highly predisposed to familial pancreatic cancer. However, genetic susceptibility to sporadic pancreatic cancer is largely uncovered. We conducted a two-stage association study on pancreatic cancer that included 981 cases and 1991 controls in the first stage followed by a second stage (2603 cases and 2877 controls). Using an approach based on candidate genes whose roles in pancreatic cancer have been well known, we identified two new susceptibility loci. rs11571836 located in the BRCA2 3′-untranslated region was significantly associated with lower expression of BRCA2 transcript and increased pancreatic cancer risk [odds ratio = 1.30, 95% confidence interval = 1.14–1.47, P = 7.64 × 10–5] in a recessive manner. rs12939944 located in the MAP2K4 intron was associated with decreased risk (odds ratio = 0.82, 95% confidence interval = 0.74–0.91, P = 0.0001) in a dominant manner. Our results demonstrate for the first time that common variants in BRCA2 and MAP2K4 are susceptibility to sporadic pancreatic cancer. [ABSTRACT FROM AUTHOR]

Despite the clinical utility of genetic diagnosis to address idiopathic sensorineural hearing impairment (SNHI), the current strategy for screening mutations via Sanger sequencing suffers from the limitation that only a limited number of DNA fragments associated with common deafness mutations can be genotyped. Consequently, a definitive genetic diagnosis cannot be achieved in many families with discernible family history. To investigate the diagnostic utility of massively parallel sequencing (MPS), we applied the MPS technique to 12 multiplex families with idiopathic SNHI in which common deafness mutations had previously been ruled out. NimbleGen sequence capture array was designed to target all protein coding sequences (CDSs) and 100 bp of the flanking sequence of 80 common deafness genes. We performed MPS on the Illumina HiSeq2000, and applied BWA, SAMtools, Picard, GATK, Variant Tools, ANNOVAR, and IGV for bioinformatics analyses. Initial data filtering with allele frequencies (<5% in the 1000 Genomes Project and 5400 NHLBI exomes) and PolyPhen2/SIFT scores (>0.95) prioritized 5 indels (insertions/deletions) and 36 missense variants in the 12 multiplex families. After further validation by Sanger sequencing, segregation pattern, and evolutionary conservation of amino acid residues, we identified 4 variants in 4 different genes, which might lead to SNHI in 4 families compatible with autosomal dominant inheritance. These included GJB2 p.R75Q, MYO7A p.T381M, KCNQ4 p.S680F, and MYH9 p.E1256K. Among them, KCNQ4 p.S680F and MYH9 p.E1256K were novel. In conclusion, MPS allows genetic diagnosis in multiplex families with idiopathic SNHI by detecting mutations in relatively uncommon deafness genes. [ABSTRACT FROM AUTHOR]

Adaptive mutations that have contributed to the emergence of influenza A pandemic (H1N1) 2009 virus, which can replicate and transmit among humans, remain unknown. We conducted a large-scale scanning of influenza protein sequences and identified amino acid-conserving positions that are specific to host species, called signatures. Of 47 signatures that separate avian viruses from human viruses by their nonglycoproteins, 8 were human-like in the pandemic (H1N1) 2009 virus. Close examination of their amino acid residues in the recent ancestral swine viruses of pandemic (H1N1) 2009 virus showed that 7 had already transitioned to human-like residues and only PA 356 retained an avian-like K; in pandemic (H1N1) 2009 virus, this residue changed into a human-like R. Signatures that separate swine viruses from human viruses were also present. Continuous monitoring of these signatures in nonhuman species will help with influenza surveillance and with evaluation of the likelihood of further adaptation to humans. [ABSTRACT FROM AUTHOR]

Febrile seizures (FS) are common in children, and the incidence is 2–5% before the age of 5 years. A four-generation Chinese family with autosomal dominant febrile seizure and epilepsy was studied by genome-wide linkage analysis. Significant linkage was identified with markers on chromosome 3q26.2–26.33 with a maximum pairwise LOD score of >3.00. Fine mapping defined the new genetic locus within a 10.7-Mb region between markers D3S3656 and D3S1232. A maximum multipoint LOD score of 5.27 was detected at marker D3S1565. A previously reported CLCN2 gene for epilepsy was excluded as the disease-causing gene in the family by mutational analysis of all exons and exon–intron boundaries of CLCN2 and by haplotype analysis. Mutation analysis of KCNMB2 and KCNMB3, which were two potassium-channel genes in this linkage region, did not reveal a disease causing mutation. Our results identified another novel locus on chromosome 3q26.2–26.33, and future studies of the candidate genes at the locus will identify a new gene for combined FS and idiopathic epilepsies. [ABSTRACT FROM AUTHOR]

Accurate epidemiological data on common deafness genes are essential to improve the efficiency and to reduce the cost of molecular diagnosis. They may depend on several factors, including a clear delineation of the source of patients being studied. In the present study, we hypothesize that patients with idiopathic sensorineural hearing loss recruited from different sources might reveal discrepancies in the epidemiological results of genetic screening, because patients from different sources might demonstrate distinct clinical or audiologic features and thus result in biased selection of subjects. To elucidate the relative importance of common deafness genes in Taiwanese and to verify our hypothesis, we conducted a prospective project screening mutations in GJB2, SLC26A4 and mitochondrial 12S rRNA gene in a total of 420 Taiwanese families with idiopathic bilateral sensorineural hearing loss, of which 325 families were recruited from hospitals and 95 from hearing rehabilitation facilities. Allele frequencies of common mutations in these three genes and distributions of the corresponding genotypes were then compared between the two groups. The allele frequencies of mutations in SLC26A4, GJB2 and mitochondrial 12S rRNA in the probands of the 420 families were 14.4, 21.7 and 3.8%, respectively. The allele frequency of SLC26A4 mutations in the hospital group was significantly higher than that in the rehabilitation facility group (16.2 vs. 8.4%, χ2-test, p < 0.05), whereas no difference in the frequencies of GJB2 mutations and mitochondrial 12S rRNA mutations was found between the two groups. Distributions of probands classified by SLC26A4 genotypes were also different between the two groups (χ2-test, p < 0.05). Accordingly, a discrepancy in the genetic screening results might exist between different sources of idiopathic hearing-impaired patients. Further analysis of audiological results and construction of a logistic regression model showed that different audiological features, namely hearing levels and hearing loss patterns, might be responsible for the unequal distributions of mutations and probands between the hospital and rehabilitation facility groups. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The 3C protease (3C[sup pro] ) of enterovirus 71 (EV71) is a good molecular target for drug discovery. Notably, this protease was found to possess RNA-binding activity. The regions responsible for RNA binding were classified as ‘KFRDI’ (positions 82–86) and ‘VGK’ (positions 154–156) in 3C[sup pro] by mutagenesis study. Although the RNA-binding regions are structurally distinct from the catalytic site of EV71 3C[sup pro] , mutations in the RNA-binding regions influenced 3C[sup pro] proteolytic activity. In contrast, mutations at the catalytic site had almost no influence on RNA binding ability. We identified certain mutations within 3C[sup pro] which abrogated both the RNA-binding activity of the expressed, recombinant, protease and the ability to rescue virus from an infectious full-length clone of EV71 (pEV71). Interestingly, mutation at position 84 from Arg(R) to Lys(K) was found to retain good RNA binding and proteolytic activity for the recombinant 3C[sup pro] ; however, no virus could be rescued when pEV71 with the R84K mutation was introduced into the infectious copy. Together, these results may provide useful information for using 3C[sup pro] as the molecular target to develop anti-EV71 agents. Copyright © 2004 National Science Council, ROC and S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Aurora A kinase (AURKA) is an important regulator in mitotic progression and is overexpressed frequently in human cancers, including hepatocellular carcinoma (HCC). Many AURKA mutations were identified in cancer patients. Overexpressing wild-type Aurka developed a low incidence of hepatic tumors after long latency in mice. However, none of the AURKA mutant animal models have ever been described. The mechanism of mutant AURKA-mediated hepatocarcinogenesis is still unclear. A novel AURKA mutation with a.a.352 Valine to Isoleucine (V352I) was identified from clinical specimens. By using liver-specific transgenic fish overexpressing both the mutant and wild-type AURKA, the AURKA(V352I)-induced hepatocarcinogenesis was earlier and much more severe than wild-type AURKA. Although an increase of the expression of lipogenic enzyme and lipogenic factor was observed in both AURKA(V352I) and AURKA(WT) transgenic fish, AURKA(V352I) has a greater probability to promote fibrosis at 3 months compared to AURKA(WT). Furthermore, the expression levels of cell cycle/proliferation markers were higher in the AURKA(V352I) mutant than AURKA(WT) in transgenic fish, implying that the AURKA(V352I) mutant may accelerate HCC progression. Moreover, we found that the AURKA(V352I) mutant activates AKT signaling and increases nuclear β-catenin, but AURKA(WT) only activates membrane form β-catenin, which may account for the differences. In this study, we provide a new insight, that the AURKA(V352I) mutation contributes to early onset hepatocarcinogenesis, possibly through activation of different pathways than AURKA(WT). This transgenic fish may serve as a drug-screening platform for potential precision medicine therapeutics. [ABSTRACT FROM AUTHOR]

Different amino acid sequences of influenza virus proteins contribute to different viral phenotypes. However, the diversity of the sequences and its impact on noncoding regions or splice sites have not been intensively studied. This study focuses on the sequences at alternative 5′ splice sites on M1 mRNA. Six different mutations at the splice sites were introduced, and viral growth characteristics for those mutants generated by reverse genetics with 12 plasmids were examined, for which G12C (the G-to-C mutation at the first nucleotide of the intron for the mRNA3 5′ splice site), C51G (at the 3′ end of the exon of the M2 mRNA 5′ splice site), and G146C (for the first nucleotide of the intron for mRNA4) are lethal mutations. On the other hand, mutants with the mutation G11C (at the 3′ end of exon of the mRNA3 5′ splice site), G52C (for the first nucleotide of the intron for M2 mRNA), or G145A (at the 3′ end of the exon of mRNA4) were rescued, although they had significantly attenuated growth rates. Notably, these mutations did not change any amino acids in M1 or M2 proteins. The levels of precursor (M1 mRNA) and spliced products (M2 mRNA, mRNA3, and mRNA4) from the recombinant mutant virus-infected cells were further analyzed. The production levels of mRNA3 in cells infected with G11C, G52C, and G145A mutant viruses were reduced in comparison with that in wild-type recombinant virus-infected ones. More M2 mRNA was produced in G11C mutant virus-infected cells than in wild-type-virus-infected cells, and there was little M2 mRNA and none at all in G145A and G52C mutant virus-infected ones, respectively. Results obtained here suggest that introducing these mutations into the alternative 5′ splice sites disturbed M1 mRNA splicing, which may attenuate viral growth rates. [ABSTRACT FROM AUTHOR]

TP53 binding protein 1 (53BP1) plays an important role in DNA damage repair and maintaining genomic stability. However, the mutations of 53BP1 in human cancers have not been systematically examined. Here, we have analyzed 541 somatic mutations of 53BP1 across 34 types of human cancer from databases of The Cancer Genome Atlas, International Cancer Genome Consortium and Catalogue of Somatic Mutations in Cancer. Among these cancer-associated 53BP1 mutations, truncation mutations disrupt the nuclear localization of 53BP1 thus abolish its biological functions in DNA damage repair. Moreover, with biochemical analyses and structural modeling, we have examined the detailed molecular mechanism by which missense mutations in the key domains causes the DNA damage repair defects. Taken together, our results reveal the functional defects of a set of cancer-associated 53BP1 mutations. [ABSTRACT FROM AUTHOR]

Besides being a predictive biomarker of response to immunotherapy in lung cancer in general, programmed death-ligand 1 (PD-L1) is not so well correlated with treatment outcomes of lung adenocarcinoma (ADC) harbouring epidermal growth factor receptor (EGFR) mutations, as reported studies are inconclusive and seldom addressed the issues of response to treatment and resistance. The primary objective is to evaluate the association of PD-L1 and EGFR tyrosine kinase inhibitor (TKI) efficacy, resistance, and relevant clinical outcomes. The secondary objective is to further explore the tumour microenvironments of EGFR mutant tumours with different PD-L1 expression. Using immunohistochemical (IHC) staining, we retrospectively tested PD-L1 expression (Dako 22C3) in the pre-treatment tumours from advanced EGFR mutant lung ADC patients, of whom all were treated with TKIs. Multiplex IHC assay was applied for exploring immune cells in tumour microenvironments. A total of 153 Taiwanese patients were enrolled in our study, of whom a majority of cases were female (58.9%) and non-smokers (75.8%). The objective response rate (ORR) to EGFR TKI and progression-free survival (PFS) were better in patients with PD-L1 expression <50% (ORR/PFS in PD-L1 0% versus 1–49% versus ≥50%: 65.6%/12.5 months versus 56.4%/12.8 months versus 38.9%/5.9 months, P < 0.05). The multivariate analysis showed that PD-L1 <50% was an independent prognostic factor for longer PFS (hazard ratio (HR) 0.433, 95% confidence interval (CI) 0.250–0.751, P = 0.003). Furthermore, tumours with higher PD-L1 expression were less likely to develop a secondary T790M mutation (T790M+ in PD-L1 0% versus 1–49% versus ≥50%: 53.7% versus 35.7% versus 10%, P = 0.024). Multiplex IHC tests were applied in 15 cases and revealed a potential correlation between PD-L1, immune cells, and EGFR TKI responses. Lower pre-treatment PD-L1 is associated with better ORR, PFS, and higher frequency of T790M resistance in EGFR TKI-treated lung ADC patients. • Pre-treatment PD-L1 can predict TKI response in EGFR mutant lung adenocarcinoma (ADC). • Pre-treatment PD-L1 can predict acquired T790M in EGFR mutant lung ADC after TKI therapy. • PD-L1 negatively correlated with B cells, macrophages, and regulatory T cells in EGFR mutant ADC. • Abundant tumour-infiltrating B cell is associated with good TKI response in EGFR mutant ADC. • Pre-treatment PD-L1 may help select the most appropriate regimen for EGFR mutant ADC. [ABSTRACT FROM AUTHOR]

The postnatal neurodevelopmental disorder Rett syndrome, caused by mutations in MECP2, produces a diverse array of symptoms, including loss of language, motor, and social skills and the development of hand stereotypies, anxiety, tremor, ataxia, respiratory dysrhythmias, and seizures. Surprisingly, despite the diversity of these features, we have found that deleting Mecp2 only from GABAergic inhibitory neurons in mice replicates most of this phenotype. Here we show that genetically restoring Mecp2 expression only in GABAergic neurons of male Mecp2 null mice enhanced inhibitory signaling, extended lifespan, and rescued ataxia, apraxia, and social abnormalities but did not rescue tremor or anxiety. Female Mecp2+/- mice showed a less dramatic but still substantial rescue. These findings highlight the critical regulatory role of GABAergic neurons in certain behaviors and suggest that modulating the excitatory/inhibitory balance through GABAergic neurons could prove a viable therapeutic option in Rett syndrome. [ABSTRACT FROM AUTHOR]

Background Pulmonary pleomorphic carcinomas (PPCs) are uncommon malignant tumours characterised by an aggressive clinical course and poor survival. These neoplasms frequently exhibit marked confluent necrosis, in which hypoxia levels are extremely high, causing low responsiveness to chemotherapy and conferring basic resistance to anti-cancer drugs. Programmed death ligand 1 (PD-L1)–mediated immune escape may be an underlying source of resistance and a suitable target for specific therapy, but its role in PPCs is unclear. Materials and methods In total, 122 PPCs were investigated. Paraffin-embedded tumour sections were stained with PD-L1 and hypoxia-inducible factor-1α (HIF-1α) antibodies. Overexpression was denoted by moderate-to-strong PD-L1 membrane staining in ≥5% of tumour cells and HIF-1α nuclear staining in ≥10% of tumour cells. The presence of driver mutations in the epidermal growth factor receptor ( EGFR ), Kirsten rat sarcoma viral oncogene homolog ( KRAS ), v-raf murine sarcoma viral oncogene homolog B ( BRAF ), telomerase reverse harscriptase gene ( TERT ), phosphoinositide 3-kinase catalytic alpha ( PIK3CA ), anaplastic lymphoma kinase ( ALK ), and ROS1 (ROS1 proto-oncogene receptor tyrosine kinase) genes were examined. Results The overall frequencies of PD-L1 and HIF-1α overexpression and EGFR mutation were 70.5, 75.4, and 22.1%, respectively. High PD-L1 expression was significantly correlated with that of HIF-1α ( p < 0.001) and tumour necrosis ( p < 0.001). HIF-1α expression was associated with EGFR mutation ( p = 0.015). Advanced stage and high PD-L1 expression were two independent risks for poor overall survival. Conclusions High PD-L1 and HIF-1α co-expression was observed in PPCs compared with their expression in conventional non-small-cell lung carcinoma. The aggressive behaviour of PPC could be partially related to PD-L1–mediated immune escape and intratumoural hypoxia. High PD-L1 expression correlates with poor prognosis and may provide a rationale for the use of targeted immunotherapy in this subtype of high-grade PPC. [ABSTRACT FROM AUTHOR]

Background Programmed cell death-ligand 1 (PD-L1) is expressed in a subgroup of lung cancer that may benefit from immunotherapy. The interaction between PD-L1 expression and tumour infiltrating lymphocytes (TIL) remains poorly understood. This study investigated the expression of PD-L1 in surgically resected stage I pulmonary squamous cell carcinoma (SqCC) and correlated it with TILs in tumour microenvironments, common driver mutations, and clinical outcomes. Materials and methods One hundred and five patients with surgically resected stage I squamous cell carcinoma were examined. Paraffin-embedded tumour sections were stained with PD-L1 antibody. Tumours with moderate-to-strong membrane staining in ≥5% of tumour cells were scored as positive for PD-L1 expression. The driver mutation epidermal growth factor receptor (EGFR), Kirsten rat sarcoma viral oncogene homolog (KRAS), and v-raf murine sarcoma viral oncogene homolog B (BRAF) were examined by direct sequencing, while anaplastic lymphoma kinase (ALK), phosphoinositide 3-kinase catalytic alpha (PI3KCA), and fibroblast growth factor receptor 1 (FGFR1) were analysed by immunohistochemistry. The correlations of PD-L1 expression with each subtype of TIL, driver mutations, clinicopathologic parameters, and clinical outcomes were analysed. Results There was positive PD-L1 expression in 56.2% (59/105) of patients. PD-L1 expression was not associated with the common clinicopathologic features and mutations of EGFR, KRAS, BRAF, ALK, PI3KCA, and FGFR1. As regards TILs composition, tumour PD-L1 expression was significantly associated with increased tumour epithelial CD8+ T cells and stromal CD4+ T cells. Otherwise, PD-L1 (+) tumour cells were negatively correlated with PD-L1 (+) immune cells within tumour stroma. By multivariate analysis, tumour PD-L1 expression and increased CD4+ T cell infiltrations in the tumour stroma were independent predictors of better overall survival and had a trend of better disease-free survival. Conclusions PD-L1 expression is associated with a favourable immune microenvironment in stage I pulmonary SqCC and correlates with better clinical outcome. [ABSTRACT FROM AUTHOR]

Mediator of DNA damage checkpoint protein 1 (MDC1) serves as a docking platform to promote the localization of various DNA damage response (DDR) components to DNA double-strand break (DSB) sites. MDC1 is vital in controlling proper DDR and maintaining genomic stability. In cancers, genomic instability results from mutations in DNA repair genes and drives cancer development. The mutations of MDC1 in human cancers have not been systematically examined and little is known about the molecular phenotypes caused by these genetic changes. Here, we summarized cancer-associated mutations of MDC1 including insertion/deletion mutations as well as missense mutations in key functional domains of MDC1 from ICGC, TCGA and COSMIC databases. We analyzed 711 somatic mutations of MDC1 across 26 types of human cancers and examined the functional defects of these cancer-associated mutations of MDC1 in the context of DNA damage repair. 6 truncation mutations and 7 missense mutations of MDC1 were chosen for further study. 6 truncation mutations which abolish MDC1-γH2AX interaction abrogate its biological functions in DNA damage repair. 2 missense mutations in FHA domain impaired ATM (ataxia telangiectasia mutated) phosphorylation. 5 missense mutations in BRCT domain also abolished its interaction with γH2AX, resulting in defects in foci formation of MDC1, 53BP1 and BRCA1 as well as defects in G2/M checkpoints. We further used structural modeling to analyze the potential molecular mechanism by which the 7 missense mutations cause the DNA damage repair defects. Taken together, our results reveal these cancer-associated MDC1 mutations can result in functional defects in DNA damage response and may serve as biomarkers for cancer diagnostics in future. • Mutations of MDC1 from three cancer databases are functional defects in DNA damage response. • Truncation mutants of MDC1 that abolish the MDC1-γH2AX interaction abrogate its biological functions in DNA damage repair. • Missense mutations of MDC1 cause defects in foci formation of MDC1, 53BP1 and BRCA1 as well as G2/M checkpoints. [ABSTRACT FROM AUTHOR]

Abstract: Background: Programmed cell death-ligand 1 (PD-L1) is expressed in a group of cancers that may be suitable targets for specific immunotherapy. This study investigated the expression of PD-L1 in surgically resected stage I adenocarcinomas and correlated this with known major driver mutations and clinical outcomes. Materials and methods: One hundred and sixty-three patients with surgically resected stage I adenocarcinomas were explored. Paraffin-embedded tumour sections were stained with PD-L1 antibody. Tumours with moderate-to-strong membrane staining in ⩾5% of tumour cells were scored as positive for PD-L1 overexpression. The driver mutation epidermal growth factor receptor (EGFR), Kirsten rat sarcoma viral oncogene homolog (KRAS), and v-raf murine sarcoma viral oncogene homolog B (BRAF) were examined by direct sequencing and anaplastic lymphoma kinsase (ALK) by immunohistochemistry. The correlations of PD-L1 expression with major driver mutations and clinicopathologic parameters were analysed. Results: The overall frequency of PD-L1 overexpression was 39.9% (65/163). PD-L1 had higher positive results in tumours with higher grade differentiation and vascular invasion and PD-L1 expression was not associated with the expressions of EGFR, KRAS, BRAF and ALK. Multivariate analysis revealed that abnormal carcinoembryonic antigen (CEA) and higher grade of differentiation were risk factors for poor relapse-free survival (RFS) and PD-L1 expression correlated with better RFS. Advanced pathologic stage was the independent risk for poor overall survival (OS). Conclusions: The PD-L1 expression can be used as a prognostic indicator predictive of RFS in patients with surgically resected stage I lung adenocarcinomas. There may be a possibility for immunotherapy targeting the PD-L1 pathway in patients with lung adenocarcinoma in the future. [Copyright &y& Elsevier]

Summary: Head and neck paragangliomas (HNPGLs) are rare, and frequently associated with germline mutations of the succinate dehydrogenase (SDH) genes, especially for familial cases. The purpose of the study is to explore SDH mutations in Chinese families with familial HNPGLs in Taiwan. Four unrelated families with familial HNPGLs were screened for germline mutations in the SDHB, SDHC and SDHD genes by direct sequencing. One hundred healthy subjects without a diagnosis or family history of HNPGLs were screened as normal controls. Immunohistochemistry with SDHB antibody was performed for a carotid body tumor. Two allele variants were identified, including p.Met1Val (c.1A>G) in the SDHD gene in one family and p.Met1Ile (c.3G>C) in the SDHD gene in the other three families. Both variants are considered pathogenic because of the absence of these variants in 100 normal controls, 100% evolutionary conservation of the p.Met1 residue, co-segregation of the variants with the phenotype of HNPGL in pedigrees, and predicted abolishment of the translation start site. The tumor cells obtained from one proband harboring c.3G>C mis-sense mutation were weak diffuse staining in the cytoplasm of tumors cells. This study demonstrates that two mis-sense mutations at the start codon of the SDHD gene, including p.Met1Val (c.1A>G) and p.Met1Ile (c.3G>C), might be mutation hotspots in Chinese patients with familial HNPGLs. [ABSTRACT FROM AUTHOR]

Purpose: Radiation-induced pneumonitis (RP) is the most common dose-limiting complication in lung cancer patients treated with radiotherapy. Accumulating evidence indicates that P53 and the ataxia telangiectasia-mutated protein (ATM)—dependent signaling response cascade play a crucial role in radiation-induced diseases. Consistent with this, our previous study showed that a functional genetic ATM polymorphism was associated with increased RP risk. Methods and Materials: To evaluate the role of genetic P53 polymorphism in RP, we analyzed the P53 Arg72Pro polymorphism in a cohort including 253 lung cancer patients receiving thoracic irradiation. Results: We found that the P53 72Arg/Arg genotype was associated with increased RP risk compared with the 72Pro/Pro genotype. Furthermore, the P53 Arg72Pro and ATM –111G>A polymorphisms display an additive combination effect in intensifying the risk of developing RP. The cross-validation test showed that 63.2% of RP cases can be identified by P53 and ATM genotypes. Conclusions: These results indicate that genetic polymorphisms in the ATM-P53 pathway influence susceptibility to RP and genotyping P53 and ATM polymorphisms might help to identify patients susceptible to developing RP when receiving radiotherapy. [ABSTRACT FROM AUTHOR]