scholarly journals Somatotroph Tumors and the Epigenetic Status of the GNAS Locus

2021 ◽  
Vol 22 (14) ◽  
pp. 7570
Author(s):  
Pauline Romanet ◽  
Justine Galluso ◽  
Peter Kamenicky ◽  
Mirella Hage ◽  
Marily Theodoropoulou ◽  
...  

Background: Forty percent of somatotroph tumors harbor recurrent activating GNAS mutations, historically called the gsp oncogene. In gsp-negative somatotroph tumors, GNAS expression itself is highly variable; those with GNAS overexpression most resemble phenotypically those carrying the gsp oncogene. GNAS is monoallelically expressed in the normal pituitary due to methylation-based imprinting. We hypothesize that changes in GNAS imprinting of gsp-negative tumors affect GNAS expression levels and tumorigenesis. Methods: We characterized the GNAS locus in two independent somatotroph tumor cohorts: one of 23 tumors previously published (PMID: 31883967) and classified by pan-genomic analysis, and a second with 82 tumors. Results: Multi-omics analysis of the first cohort identified a significant difference between gsp-negative and gsp-positive tumors in the methylation index at the known differentially methylated region (DMR) of the GNAS A/B transcript promoter, which was confirmed in the larger series of 82 tumors. GNAS allelic expression was analyzed using a polymorphic Fok1 cleavage site in 32 heterozygous gsp-negative tumors. GNAS expression was significantly reduced in the 14 tumors with relaxed GNAS imprinting and biallelic expression, compared to 18 tumors with monoallelic expression. Tumors with relaxed GNAS imprinting showed significantly lower SSTR2 and AIP expression levels. Conclusion: Altered A/B DMR methylation was found exclusively in gsp-negative somatotroph tumors. 43% of gsp-negative tumors showed GNAS imprinting relaxation, which correlated with lower GNAS, SSTR2 and AIP expression, indicating lower sensitivity to somatostatin analogues and potentially aggressive behavior.

2009 ◽  
Vol 21 (9) ◽  
pp. 83
Author(s):  
Y. Liu ◽  
C. Fitzsimmons ◽  
Z. Kruk ◽  
M. Deland ◽  
S. Maddocks ◽  
...  

The multifunctional insulin-like growth factor 2 receptor (IGF2R) facilitates endocytosis and subsequent clearance or activation of a variety of ligands involved in cell growth and motility. Thus, the IGF2R gene has a major role in embryonic development and fetal growth. Murine Igf2r is subject to genomic imprinting and maternally expressed in peripheral fetal tissues. However, data on imprinting of IGF2R in human is still controversial with biallelic expression, partial imprinting, and monoallelic expression reported for fetal tissues [1, 2, 3]. Data from additional species may help to understand fetal IGF2R expression. The bovine is similar to human in that it is outbred and monotocous. We have analysed bovine Day 153 fetuses (55% to term, n=40) with Bos primigenius indicus and B. p. taurus genetics to determine the imprinting status of IGF2R in fetal brain, liver and skeletal muscle. Sequencing of PCR amplicons from IGF2R exon 48 revealed a polymorphic microsatellite and 14 SNPs. These were used to identify 15 heterozygous fetuses informative for imprinting analysis. We found biallelic expression of IGF2R in fetal brain and predominantly maternal expression in fetal liver and skeletal muscle. However, we observed considerable plasticity in imprinting in liver and skeletal muscle with paternal expression levels of 7%-21% and 4%-21%, respectively. Fetal liver samples with B. p. indicus maternal genetics showed significantly higher mean paternal expression levels than those with B. p. taurus maternal genetics (P<0.05). Real-time qPCR showed a significant relationship between imprinting and total IGF2R expression level within both tissues (P<0.05). Our data indicate plasticity in imprinting of IGF2R that could fine tune expression levels in fetal tissues.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Cheng-Lin Xu ◽  
Wei-Qun Guan ◽  
Xue-Ying Wang

Abstract Background This study aimed to investigate the expression level of the GATA6 gene in different oral cancer cells. Methods In this study, we sub-cultured normal oral epithelial cell lines HOK, human tongue squamous cell carcinoma cell lines CAL-27 and SCC-4, and human salivary gland adenoid cystic carcinoma cell lines SACC-LM and SACC-83. Subsequently, we used reverse transcription-polymerase chain reaction RT-PCR and Western blot methods to detect the mRNA and the protein expressions of GATA6 in normal oral epithelial cells, human tongue squamous cell carcinoma cells, and human salivary gland adenoid cystic carcinoma cells. Results The results of this study showed that the mRNA expression levels of GATA6 in CAL-27, SCC-4, and SACC-LM cells were significantly increased when compared with the HOK cells. However, the mRNA expression level of GATA6 in the SACC-83 cells had no significant difference compared with the HOK cells. The protein expression levels of GATA6 in the SCC-4 and SACC-LM cells were, however, significantly increased whereas the protein expression levels of GATA6 in the CAL-27 and SACC-83 cells had no significant difference when compared with the HOK cells. Conclusion The GATA6 gene may be related to the occurrence and progression of certain oral cancers.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Elizabeth Ruiz-Sánchez ◽  
Janet Jiménez-Genchi ◽  
Yessica M. Alcántara-Flores ◽  
Carlos J. Castañeda-González ◽  
Carlos L. Aviña-Cervantes ◽  
...  

Abstract Background Cognitive functions represent useful endophenotypes to identify the association between genetic variants and schizophrenia. In this sense, the NR4A2 gene has been implicated in schizophrenia and cognition in different animal models and clinical trials. We hypothesized that the NR4A2 gene is associated with working memory performance in schizophrenia. This study aimed to analyze two variants and the expression levels of the NR4A2 gene with susceptibility to schizophrenia, as well as to evaluate whether possession of NR4A2 variants influence the possible correlation between gene expression and working memory performance in schizophrenia. Methods The current study included 187 schizophrenia patients and 227 controls genotyped for two of the most studied NR4A2 genetic variants in neurological and neuropsychiatric diseases. Genotyping was performed using High Resolution Melt and sequencing techniques. In addition, mRNA expression of NR4A2 was performed in peripheral mononuclear cells of 112 patients and 118 controls. A group of these participants, 54 patients and 87 controls, performed the working memory index of the WAIS III test. Results Both genotypic frequencies of the two variants and expression levels of the NR4A2 gene showed no significant difference when in patients versus controls. However, patients homozygous for the rs34884856 promoter variant showed a positive correlation between expression levels and auditory working memory. Conclusions Our finding suggested that changes in expression levels of the NR4A2 gene could be associated with working memory in schizophrenia depending on patients’ genotype in a sample from a Mexican population.


Author(s):  
Eman Ragab ◽  
Asrar Helal Mahrous ◽  
Ghadeer Maher El Sheikh

Abstract Background High-resolution computed tomography (HRCT) has proved to be an important diagnostic tool throughout the COVID-19 pandemic outbreaks. Increasing number of the infected personnel and shortage of real-time transcriptase polymerase chain reaction (RT-PCR) as well as its lower sensitivity made the CT a backbone in diagnosis, assessment of severity, and follow-up of the cases. Results Two hundred forty patients were evaluated retrospectively for clinical, laboratory, and radiological expression in COVID-19 infection. One hundred eighty-six non-severe cases with home isolation and outpatient treatment and 54 severe cases needed hospitalization and oxygen support. Significant difference between both groups was encountered regarding the age, male gender, > 38° fever, dyspnea, chest pain, hypertension, ≤ 93 oxygen saturation, intensive care unit (ICU) admission, elevated D-dimer, high serum ferritin and troponin levels, and high CT-severity score (CT-SS) of the severe group. CT-SS showed a negative correlation with O2 saturation and patients’ outcome (r − 0.73/p 0.001 and r − 0.56/p 0.001, respectively). Bilateral peripherally distributed ground glass opacities (GGOs) were the commonest imaging feature similar to the literature. Conclusion Older age, male gender, smoking, hypertension, low O2 saturation, increased CT score, high serum ferritin, and high D-dimer level are the most significant risk factors for severe COVID-19 pneumonia. Follow-up of the recovered severe cases is recommended to depict possible post COVID-19 lung fibrosis.


2021 ◽  
Vol 10 (Supplement_1) ◽  
pp. S1-S1
Author(s):  
T Kitano ◽  
M Science ◽  
N Nalli ◽  
K Timberlake ◽  
U Allen ◽  
...  

Abstract Background Solid-organ transplant (SOT) patients are more vulnerable to infections by antimicrobial-resistant organisms (AROs) because of their hospital exposure, compromised immune systems, and antimicrobial exposure. Therefore, it may be useful for transplant facilities to create transplant-specific antibiograms to direct empirical antimicrobial regimens and monitor trends in antimicrobial resistance. Methods SOT (i.e., lung, liver, renal, and heart) antibiograms were created using antimicrobial susceptibility data on isolates from 2012 to 2018 at The Hospital for Sick Children, a tertiary pediatric hospital and transplant center in Toronto, Ontario. The Clinical Laboratory Standards Institute (CLSI) guidelines were followed to generate the antibiograms. The first clinical isolate of a species from a patient in each year was included irrespective of body site; duplicates were eliminated and surveillance cultures were excluded. Results from 2 years of data were pooled on a rolling basis to achieve an adequate sample size in both SOT and hospital-wide antibiogram. The SOT antibiogram was then compared with the hospital-wide antibiogram of the compatible 2 pooled years from 2012 to 2018. For subgroup analyses in the SOT population, organ-specific antibiograms and transplant timing-specific antibiograms (pretransplant, post-transplant &lt;1 year, and post-transplant ≥1 year) between transplant and sample collection dates were analyzed. All proportions were compared using the χ 2 test. Results The top 5 organisms in one (2 year) analysis period of the SOT antibiogram were Escherichia coli (n = 29), Staphylococcus aureus (n = 28), Pseudomonas aeruginosa (n = 20), Enterobacter cloacae complex (n = 18), and Klebsiella pneumoniae (n = 17). For E.coli, susceptibility in the SOT antibiogram was significantly lower than those in the hospital-wide antibiogram in 2017/2018 for ampicillin (27% vs. 48%; P = 0.015), piperacillin/tazobactam (55% vs. 87%; P &lt; 0.001), cefotaxime (59% vs. 88%; P &lt; 0.001), ciprofloxacin (71% vs. 87%; P = 0.007) and cotrimoxazole (41% vs. 69%; P &lt; 0.001), but not significantly different for gentamicin (94% vs. 91%; P = 0.490), tobramycin (88% vs. 90%; P = 0.701) and amikacin (100% vs. 99%; P = 0.558). These findings were consistent throughout the study period in E.coli. There was no statistically significant difference between the SOT and hospital-wide antibiograms for other organisms. There were no significant differences in susceptibility between organ-specific antibiograms or transplant timing-specific antibiograms in 2012–2018. Conclusions We found that E.coli from the SOT population had a significantly lower sensitivity to all antimicrobials, except aminoglycosides, compared with those from the hospital-wide population. Other organisms had similar susceptibility to the hospital-wide population. Developing a SOT antibiogram will assist in revising and improving empiric treatment guidelines for this population.


2018 ◽  
Vol 107 (3) ◽  
pp. 257-266 ◽  
Author(s):  
Jerena Manoharan ◽  
Volker Fendrich ◽  
Pietro Di Fazio ◽  
Carmen Bollmann ◽  
Silvia Roth ◽  
...  

Pancreatic neuroendocrine neoplasias (pNEN) are the most common cause of death in adult patients with multiple endocrine neoplasia type 1 (MEN1). So far, only few chemopreventive strategies (e.g., with somatostatin analogues) have been evaluated for MEN1 associated pNENs. In this experimental study on 75 Men1(+/T) knockout mice, the effect of aspirin (n = 25) and an inhibitor of angiotensin-I converting enzyme (enalapril, n = 25) compared to controls (n = 25) were evaluated as single chemopreventive strategies for pNENs after 6, 9, 12, 15, and 18 months. After each study period, mice were sacrificed and the resected pancreata were evaluated by histopathological analysis, immunostaining, and real-time PCR. PNEN size and number was measured. Aspirin and enalapril lead to a pNEN size reduction of 80% (167,518 vs. 838,876 µm2, p < 0.001) and 79% (174,758 vs. 838,876 µm2, p < 0.001) compared to controls. Furthermore, aspirin and enalapril treatment resulted in a significant reduction of the number of pNENs by 33%, (p = 0.04) and 41% (p = 0.002) respectively. The apoptosis marker caspase 3 revealed a higher positive expression in pNEN of treated Men1(+/T) mice. Immunostaining of VEGF in pNEN detected a downregulation of its expression in treated Men1(+/T) mice compared to the control group. REL A transcript was significantly downregulated in 18-months treated enalapril Men1(+/T) mice, but not in aspirin-treated Men1(+/T) mice. There was no significant difference in the Ki-67 index. Using a transgenic mouse model that imitates human MEN1, this study provides first evidence that aspirin and enalapril are effective chemopreventive agents that aid in the progression of pNENs.


2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Rongjie Zhang ◽  
Yan Chen ◽  
Ge Zhou ◽  
Baoguo Sun ◽  
Yue Li ◽  
...  

Objectives. The purpose of this study was to identify the molecular mechanism and prognosis-related genes of Jianpi Jiedu decoction in the treatment of hepatocellular carcinoma. Methods. The gene expression data of hepatocellular carcinoma samples and normal tissue samples were downloaded from TCGA database, and the potential targets of drug composition of Jianpi Jiedu decoction were obtained from TCMSP database. The genes were screened out in order to obtain the expression of these target genes in patients with hepatocellular carcinoma. The differential expression of target genes was analyzed by R software, and the genes related to prognosis were screened by univariate Cox regression analysis. Then, the LASSO model was constructed for risk assessment and survival analysis between different risk groups. At the same time, independent prognostic analysis, GSEA analysis, and prognostic analysis of single gene in patients with hepatocellular carcinoma were performed. Results. 174 compounds of traditional Chinese medicine were screened by TCMSP database, corresponding to 122 potential targets. 39 upregulated genes and 9 downregulated genes were screened out. A total of 20 candidate prognostic related genes were screened out by univariate Cox analysis, of which 12 prognostic genes were involved in the construction of the LASSO regression model. There was a significant difference in survival time between the high-risk group and low-risk group ( p < 0.05 ). Among the genes related to prognosis, the expression levels of CCNB1, NQO1, NUF2, and CHEK1 were high in tumor tissues ( p < 0.05 ). Survival analysis showed that the high expression levels of these four genes were significantly correlated with poor prognosis of HCC ( p < 0.05 ). GSEA analysis showed that the main KEGG enrichment pathways were lysine degradation, folate carbon pool, citrate cycle, and transcription factors. Conclusions. In the study, we found that therapy target genes of Jianpi Jiedu decoction were mainly involved in metabolism and apoptosis in hepatocellular carcinoma, and there was a close relationship between the prognosis of hepatocellular carcinoma and the genes of CCNB1, NQO1, NUF2, and CHEK1.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Amany H. Abdelrahman ◽  
Ola M. Eid ◽  
Mona H. Ibrahim ◽  
Safa N. Abd El-Fattah ◽  
Maha M. Eid ◽  
...  

Abstract Background Autism spectrum disorder is a condition related to brain development that affects a person’s perception and socialization, resulting in problems in social interaction and communication. It has no single known cause, yet several different genes appear to be involved in autism. As a genetically complex disease, dysregulation of miRNA expression and miRNA–mRNA interactions might be a feature of autism spectrum disorder. The aim of the current study was to investigate the expression profile of circulating miRNA-128, miRNA-7 and SHANK gene family in ASD patients and to assess the possible influence of miRNA-128 and miRNA-7 on SHANK genes, which might provide an insight into the pathogenic mechanisms of ASD and introduce noninvasive molecular biomarkers for the disease diagnosis and prognosis. Quantitative real-time PCR technique was employed to determine expression levels of miRNA-128, miRNA-7 and SHANK gene family in blood samples of 40 autistic cases along with 30 age- and sex-matched normal volunteer subjects. Results Our study revealed a statistical significant upregulation of miRNA-128 expression levels in ASD cases compared to controls (p value < 0.001). A statistical significant difference in SHANK-3 expression was encountered on comparing cases to controls (p value < 0.001). However, miRNA-7 expression showed no significant difference between the studied groups. Conclusions MiRNA-128 and SHANK-3 gene are emerging players in the field of ASD. They are promising candidates as noninvasive biomarkers in autism. Future studies are needed to emphasize their pivotal role.


2020 ◽  
Author(s):  
fujuan qiu ◽  
Chen Yong ◽  
Qiu Fujuan ◽  
Zhao Xiaofeng ◽  
Xiao Changhong

Abstract Background To determine whether any differences of AIM2 inflammasome expression levels between rheumatoid arthritis (RA) and osteoarthritis (OA) and investigate the effects of AIM2 when transferred into RA fibroblast-like synoviocytes (RA-FLS).Methods Serum AIM2 levels between OA and RA patients were compared by ELISA. Different expression levels of AIM2, ASC, Caspase-1 and IL-1β between RA and OA synovium were semi-quantified by RT-qPCR and immunohistochemical (IHC) staining. IHC staining were recorded by H scores, and determine the correlation with ESR and CRP levels of RA patients. SiRNA AIM2 was transferred to RA-FLS and observe its effects on proliferation and migration by MTT assay and transwell test respectively.Results In RA sera, no significant difference was observed between OA and RA patients. However, in affected knee synovium, AIM2, ASC, Caspase-1 and IL-1β were expressed higher in RA than that of OA. Plus, H score of AIM2, ASC, and IL-1β were positively correlated to ESR and CRP levels in RA patients. After transferred AIM2 siRNA to FLS and incubation for 48 hours, the proliferation of FLS were significantly inhibited, and the apoptosis rate were significantly increased compared to FLS in control group. However, no effect on migration was detected.Conclusions AIM2 participated in the proliferation of FLS, and might be a potential target for therapy.


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