SKY analysis revealed recurrent numerical and structural chromosome changes in BDII rat endometrial carcinomas

<p>Abstract</p> <p>Background</p> <p>Genomic alterations are common features of cancer cells, and some of these changes are proven to be neoplastic-specific. Such alterations may serve as valuable tools for diagnosis and classification of tumors, prediction of clinical outcome, disease monitoring, and choice of therapy as well as for providing clues to the location of crucial cancer-related genes.</p> <p>Endometrial carcinoma (EC) is the most frequently diagnosed malignancy of the female genital tract, ranking fourth among all invasive tumors affecting women. Cytogenetic studies of human ECs have not produced very conclusive data, since many of these studies are based on karyotyping of limited number of cases and no really specific karyotypic changes have yet been identified. As the majority of the genes are conserved among mammals, the use of inbred animal model systems may serve as a tool for identification of underlying genes and pathways involved in tumorigenesis in humans. In the present work we used spectral karyotyping (SKY) to identify cancer-related aberrations in a well-characterized experimental model for spontaneous endometrial carcinoma in the BDII rat tumor model.</p> <p>Results</p> <p>Analysis of 21 experimental ECs revealed specific nonrandom numerical and structural chromosomal changes. The most recurrent numerical alterations were gains in rat chromosome 4 (RNO4) and losses in RNO15. The most commonly structural changes were mainly in form of chromosomal translocations and were detected in RNO3, RNO6, RNO10, RNO11, RNO12, and RNO20. Unbalanced chromosomal translocations involving RNO3p was the most commonly observed structural changes in this material followed by RNO11p and RNO10 translocations.</p> <p>Conclusion</p> <p>The non-random nature of these events, as documented by their high frequencies of incidence, is suggesting for dynamic selection of these changes during experimental EC tumorigenesis and therefore for their potential contribution into development of this malignancy. Comparative molecular analysis of the identified genetic changes in this tumor model with those reported in the human ECs may provide new insights into underlying genetic changes involved in EC development and tumorigenesis.</p

Lowered expression of tumor suppressor candidate MYO1C stimulates cell proliferation, suppresses cell adhesion and activates AKT

Myosin-1C (MYO1C) is a tumor suppressor candidate located in a region of recurrent losses distal to TP53. Myo1c can tightly and specifically bind to PIP2, the substrate of Phosphoinositide 3-kinase (PI3K), and to Rictor, suggesting a role for MYO1C in the PI3K pathway. This study was designed to examine MYO1C expression status in a panel of wellstratified endometrial carcinomas as well as to assess the biological significance of MYO1C as a tumor suppressor in vitro. We found a significant correlation between the tumor stage and lowered expression of MYO1C in endometrial carcinoma samples. In cell transfection experiments, we found a negative correlation between MYO1C expression and cell proliferation, and MYO1C silencing resulted in diminished cell migration and adhesion. Cells expressing excess of MYO1C had low basal level of phosphorylated protein kinase B (PKB, a.k.a. AKT) and cells with knocked down MYO1C expression showed a quicker phosphorylated AKT (pAKT) response in reaction to serum stimulation. Taken together the present study gives further evidence for tumor suppressor activity of MYO1C and suggests MYO1C mediates its tumor suppressor function through inhibition of PI3K pathway and its involvement in loss of contact inhibition.Royal Physiographic Society in Lund (Nilsson-Ehle Foundation) with grant numbers 30928, 32705 and 36388: KV. Wilhelm and Martina Lundgren Foundation: KV, AB. Assar Gabrielsson Research Foundation for Clinical Cancer Research with grant numbers FB11-15, FB12-26, FB13-05, FB14-46 and FB15-45: KV. Sahlgrenska University Hospital Foundation with grant number 8181: KV. The Knowledge Foundation with grant number HOÈ G12, 20120311: AB.http://www.plosone.orgam2016Physiolog

No germline mutations in supposed tumour suppressor genes SAFB1 and SAFB2 in familial breast cancer with linkage to 19p

<p>Abstract</p> <p>Background</p> <p>The scaffold attachment factor B1 and B2 genes, <it>SAFB1/SAFB2 </it>(both located on chromosome 19p13.3) have recently been suggested as tumour suppressor genes involved in breast cancer development. The assumption was based on functional properties of the two genes and loss of heterozygosity of intragenic markers in breast tumours further strengthened the postulated hypothesis. In addition, linkage studies in Swedish breast cancer families also indicate the presence of a susceptibility gene for breast cancer at the 19p locus. Somatic mutations in <it>SAFB1/SAFB2 </it>have been detected in breast tumours, but to our knowledge no studies on germline mutations have been reported. In this study we investigated the possible involvement of <it>SAFB1/SAFB2 </it>on familiar breast cancer by inherited mutations in either of the two genes.</p> <p>Results</p> <p>Mutation analysis in families showing linkage to the <it>SAFB1/2 </it>locus was performed by DNA sequencing. The complete coding sequence of the two genes <it>SAFB1 </it>and <it>SAFB2 </it>was analyzed in germline DNA from 31 affected women. No missense or frameshift mutations were detected. One polymorphism was found in <it>SAFB1 </it>and eight polymorphisms were detected in <it>SAFB2</it>. MLPA-anlysis showed that both alleles of the two genes were preserved which excludes gene inactivation by large deletions.</p> <p>Conclusion</p> <p><it>SAFB1 </it>and <it>SAFB2 </it>are not likely to be causative of the hereditary breast cancer syndrome in west Swedish breast cancer families.</p

Molecular classification of spontaneous endometrial adenocarcinomas in BDII rats.

Female rats of the BDII/Han inbred strain are prone to spontaneously develop endometrial carcinomas (EC) that in cell biology and pathogenesis are very similar to those of human. Human EC are classified into two major groups: Type I displays endometroid histology, is hormone-dependent, and characterized by frequent microsatellite instability and PTEN, K-RAS, and CTNNB1 (beta-Catenin) mutations; Type II shows non-endometrioid histology, is hormone-unrelated, displays recurrent TP53 mutation, CDKN2A (P16) inactivation, over-expression of ERBB2 (Her2/neu), and reduced CDH1 (Cadherin 1 or E-Cadherin) expression. However, many human EC have overlapping clinical, morphologic, immunohistochemical, and molecular features of types I and II. The EC developed in BDII rats can be related to type I tumors, since they are hormone-related and histologically from endometrioid type. Here, we combined gene sequencing (Pten, Ifr1, and Ctnnb1) and real-time gene expression analysis (Pten, Cdh1, P16, Erbb2, Ctnnb1, Tp53, and Irf1) to further characterize molecular alterations in this tumor model with respect to different subtypes of EC in humans. No mutation in Pten and Ctnnb1 was detected, whereas three tumors displayed sequence aberrations of the Irf1 gene. Significant down regulation of Pten, Cdh1, p16, Erbb2, and Ctnnb1 gene products was found in the tumors. In conclusion, our data suggest that molecular features of spontaneous EC in BDII rats can be related to higher-grade human type I tumors and thus, this model represents an excellent experimental tool for research on this malignancy in human

Molecular classification of spontaneous endometrial adenocarcinomas in BDII rats.

Female rats of the BDII/Han inbred strain are prone to spontaneously develop endometrial carcinomas (EC) that in cell biology and pathogenesis are very similar to those of human. Human EC are classified into two major groups: Type I displays endometroid histology, is hormone-dependent, and characterized by frequent microsatellite instability and PTEN, K-RAS, and CTNNB1 (beta-Catenin) mutations; Type II shows non-endometrioid histology, is hormone-unrelated, displays recurrent TP53 mutation, CDKN2A (P16) inactivation, over-expression of ERBB2 (Her2/neu), and reduced CDH1 (Cadherin 1 or E-Cadherin) expression. However, many human EC have overlapping clinical, morphologic, immunohistochemical, and molecular features of types I and II. The EC developed in BDII rats can be related to type I tumors, since they are hormone-related and histologically from endometrioid type. Here, we combined gene sequencing (Pten, Ifr1, and Ctnnb1) and real-time gene expression analysis (Pten, Cdh1, P16, Erbb2, Ctnnb1, Tp53, and Irf1) to further characterize molecular alterations in this tumor model with respect to different subtypes of EC in humans. No mutation in Pten and Ctnnb1 was detected, whereas three tumors displayed sequence aberrations of the Irf1 gene. Significant down regulation of Pten, Cdh1, p16, Erbb2, and Ctnnb1 gene products was found in the tumors. In conclusion, our data suggest that molecular features of spontaneous EC in BDII rats can be related to higher-grade human type I tumors and thus, this model represents an excellent experimental tool for research on this malignancy in human

Association of TNF-α (-308G/A) Gene Polymorphism with Changes in Circulating TNF-α Levels in Response to CPAP Treatment in Adults with Coronary Artery Disease and Obstructive Sleep Apnea

Rationale: We recently demonstrated that patients with coronary artery disease (CAD) and obstructive sleep apnea (OSA) carrying the tumor necrosis factor-alpha (TNF-α) A allele had increased circulating TNF-α levels compared with the ones carrying the TNF-α G allele. In the current study, we addressed the effect of TNF-α (-308G/A) gene polymorphism on circulating TNF-α levels following continuous positive airway pressure (CPAP) therapy. Methods: This study was a secondary analysis of the RICCADSA trial (NCT00519597) conducted in Sweden. CAD patients with OSA (apnea–hypopnea index) of ≥15 events/h and an Epworth Sleepiness Scale (ESS) score of &lt;10 were randomized to CPAP or no-CPAP groups, and OSA patients with an ESS score of ≥10 were offered CPAP treatment. Blood samples were obtained at baseline and 12-month follow-up visits. TNF-α was measured by immunoassay (Luminex, R&amp;D Systems). Genotyping of TNF-α-308G/A (single nucleotide polymorphism Rs1800629) was performed by polymerase chain reaction–restriction fragment length polymorphism. Results: In all, 239 participants (206 men and 33 women; mean age 64.9 (SD 7.7) years) with polymorphism data and circulating levels of TNF-α at baseline and 1-year follow-up visits were included. The median circulating TNF-α values fell in both groups between baseline and 12 months with no significant within- or between-group differences. In a multivariate linear regression model, a significant change in circulating TNF-α levels from baseline across the genotypes from GA to GA and GA to AA (standardized β-coefficient −0.129, 95% confidence interval (CI) −1.82; −0.12; p = 0.025) was observed in the entire cohort. The association was more pronounced among the individuals who were using the device for at least 4 h/night (n = 86; standardized β-coefficient −2.979 (95% CI −6.11; −1.21); p = 0.004)), whereas no significant association was found among the patients who were non-adherent or randomized to no-CPAP. The participants carrying the TNF-α A allele were less responsive to CPAP treatment regarding the decline in circulating TNF-α despite CPAP adherence (standardized β-coefficient −0.212, (95% CI −5.66; −1.01); p = 0.005). Conclusions: Our results suggest that TNF-α (-308G/A) gene polymorphism is associated with changes in circulating TNF-α levels in response to CPAP treatment in adults with CAD and OSA. CC BY 4.0© 2023 by the authors.Correspondence: [email protected] study was supported by grants from the Swedish Research Council (521-2011-537 and 521-2013-3439); the Swedish Heart–Lung Foundation (20080592, 20090708, and 20100664); the “Agreement concerning research and education of doctors” of Västra Götalandsregionen (ALFGBG-11538 and ALFGBG-150801); the research fund at Skaraborg Hospital (VGSKAS-4731, VGSKAS-5908,VGSKAS-9134, VGSKAS-14781, VGSKAS-40271, and VGSKAS-116431); Skaraborg Research and Development Council (VGFOUSKB-46371); Lund University; the Heart Foundation of Kärnsjukhuset; the ResMed Foundation; and ResMed Ltd. None of the funders had any direct influence on the design of the study, the analysis of the data, data collection, the drafting of the manuscript, or the decision to publish.</p

BAC CGH-array identified specific small-scale genomic imbalances in diploid DMBA-induced rat mammary tumors.

ABSTRACT: BACKGROUND: Development of breast cancer is a multistage process influenced by hormonal and environmental factors as well as by genetic background. The search for genes underlying this malignancy has recently been highly productive, but the etiology behind this complex disease is still not understood. In studies using animal cancer models, heterogeneity of the genetic background and environmental factors is reduced and thus analysis and identification of genetic aberrations in tumors may become easier. To identify chromosomal regions potentially involved in the initiation and progression of mammary cancer, in the present work we subjected a subset of experimental mammary tumors to cytogenetic and molecular genetic analysis. METHODS: Mammary tumors were induced with DMBA (7,12-dimethylbenz[a]anthrazene) in female rats from the susceptible SPRD-Cu3 strain and from crosses and backcrosses between this strain and the resistant WKY strain. We first produced a general overview of chromosomal aberrations in the tumors using conventional kartyotyping (G-banding) and Comparative Genome Hybridization (CGH) analyses. Particular chromosomal changes were then analyzed in more details using an in-house developed BAC (bacterial artificial chromosome) CGH-array platform. RESULTS: Tumors appeared to be diploid by conventional karyotyping, however several sub-microscopic chromosome gains or losses in the tumor material were identified by BAC CGH-array analysis. An oncogenetic tree analysis based on the BAC CGH-array data suggested gain of rat chromosome (RNO) band 12q11, loss of RNO5q32 or RNO6q21 as the earliest events in the development of these mammary tumors. CONCLUSIONS: Some of the identified changes appear to be more specific for DMBA-induced mammary tumors and some are similar to those previously reported in ACI rat model for estradiol-induced mammary tumors. The later group of changes is more interesting, since they may represent anomalies that involve genes with a critical role in mammary tumor development. Genetic changes identified in this work are at very small scales and thus may provide a more feasible basis for the identification of the target gene(s). Identification of the genes underlying these chromosome changes can provide new insights to the mechanisms of mammary carcinogenesis.JOURNAL ARTICLESCOPUS: ar.jinfo:eu-repo/semantics/publishe

Association of TNF-alpha (-308G/A) Gene Polymorphism with Circulating TNF-alpha Levels and Excessive Daytime Sleepiness in Adults with Coronary Artery Disease and Concomitant Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is common in patients with coronary artery disease (CAD), in which inflammatory activity has a crucial role. The manifestation of OSA varies significantly between individuals in clinical cohorts; not all adults with OSA demonstrate the same set of symptoms; i.e., excessive daytime sleepiness (EDS) and/or increased levels of inflammatory biomarkers. The further exploration of the molecular basis of these differences is therefore essential for a better understanding of the OSA phenotypes in cardiac patients. In this current secondary analysis of the Randomized Intervention with Continuous Positive Airway Pressure in CAD and OSA (RICCADSA) trial (Trial Registry: ClinicalTrials.gov; No: NCT 00519597), we aimed to address the association of tumor necrosis factor alpha (TNF-α)-308G/A gene polymorphism with circulating TNF-α levels and EDS among 326 participants. CAD patients with OSA (apnea–hypopnea-index (AHI) ≥ 15 events/h; n = 256) were categorized as having EDS (n = 100) or no-EDS (n = 156) based on the Epworth Sleepiness Scale score with a cut-off of 10. CAD patients with no-OSA (AHI &lt; 5 events/h; n = 70) were included as a control group. The results demonstrated no significant differences regarding the distribution of the TNF-α alleles and genotypes between CAD patients with vs. without OSA. In a multivariate analysis, the oxygen desaturation index and TNF-α genotypes from GG to GA and GA to AA as well as the TNF-α-308A allele carriage were significantly associated with the circulating TNF-α levels. Moreover, the TNF-α-308A allele was associated with a decreased risk for EDS (odds ratio 0.64, 95% confidence interval 0.41–0.99; p = 0.043) independent of age, sex, obesity, OSA severity and the circulating TNF-α levels. We conclude that the TNF-α-308A allele appears to modulate circulatory TNF-α levels and mitigate EDS in adults with CAD and concomitant OSA.CC BY 4.0</p