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Obsessive-compulsive disorder (OCD) represents a heterogeneous collection of diseases with diverse levels of phenotypic, genetic, and etiologic variability, making it difficult to identify the underlying genetic and biological mechanisms in humans. Domestic dogs exhibit several OCD-like behaviors. Using continuous circling as a representative phenotype for OCD, we screened two independent dog breeds, the Belgian Malinois and Kunming Dog and subsequently sequenced ten circling dogs and ten unaffected dogs for each breed. Using population differentiation analyses, we identified 11 candidate genes in the extreme tail of the differentiated regions between cases and controls. These genes overlap significantly with genes identified in a genome wide association study (GWAS) of human OCD, indicating strong convergence between humans and dogs. Through gene expressional analysis and functional exploration, we found that two candidate OCD risk genes, PPP2R2B and ADAMTSL3, affected the density and morphology of dendritic spines. Therefore, changes in dendritic spine may underlie some common biological and physiological pathways shared between humans and dogs. Our study revealed an unprecedented level of convergence in OCD shared between humans and dogs, and highlighted the importance of using domestic dogs as a model species for many human diseases including OCD.

Background Although immune checkpoint blockade has emerged as a novel promising strategy for triple-negative breast cancer (TNBC), many patients fail response or acquire resistance to current agents. Consequently, our focus need to shift toward alternative inhibitory targets, predictor for responsiveness, and immune suppressive mechanisms. Methods In this study, we performed systematic bioinformatics analyses to identify PPP2R2B as a robust tumor suppressor in TNBC. Meanwhile, breast cancer progression cell line model was applied in our research. Quantitative real-time PCR assay (Q-PCR) was carried out to assess the role of PPP2R2B in the onset and progression of breast cancer. Furthermore, we validated the effect of PPP2R2B on immune activity via in vitro experiments based on macrophages. To further decipher the roles of PPP2R2B in TNBC, we investigated the transcriptome level, genomic profiles, and its clinical prognostic value. Results In TNBC tissues, PPP2R2B expression was significantly downregulated compared to normal breast tissues. Kaplan‐Meier survival analysis revealed that patients with low PPP2R2B expression had shorter survival time than those with high PPP2R2B expression. Q-PCR analysis suggested that PPP2R2B downregulation could play a key role in breast-cancer initiation and progression. Additionally, our findings showed that PPP2R2B was positively related with CD8 T cells, CD4 Th1 helper cells, and M1 macrophages, but negatively related with M2 macrophages. Subsequent results identified that PPP2R2B was strongly related with immune inhibitor genes (GZMA, PRF1, and IFNG), which could improve T lymphocytes antitumor function and restrict immune evasion. Meanwhile, T cell receptor signaling pathway and antigen processing and presentation signaling pathway were significantly suppressed in low PPP2R2B expression group. Afterwards, distinct subgroups based on PPP2R2B expression exhibited several unique features in somatic mutations, copy numbers alterations, extent of copy number burden, and promoter methylation level. Conclusion Our results indicated that PPP2R2B could serve as a promising biomarker for TNBC, and help predict immunotherapeutic response and guide personalized strategies in TNBC treatment.

The Cancer Genome Atlas (TCGA) Research Network confirmed that undifferentiated pleomorphic sarcoma (UPS) and myxofibrosarcoma (MFS) share a high level of genomic similarities and fall into a single spectrum of tumour. However, no molecular prognostic biomarkers have been identified in UPS/MFS. In this study, by extracting data from TCGA‐Sarcoma (SARC), we explored relapse‐related genes, their prognostic value and possible mechanisms of the dysregulations. After systematic screening, ITGA10 and PPP2R2B were included to construct a 2‐gene signature. The 2‐gene signature had an AUC value of 0.83 and had an independent prognostic value in relapse‐free survival (RFS) (HR: 2.966, 95%CI: 1.995‐4.410 P .4) with PPP2R2B expression. Besides, the 2‐gene signature showed a moderate negative correlation with CD4 + T cell infiltration. High‐level CD4 + T cell infiltration and neutrophil infiltration were associated with significantly better RFS. Based on these findings, we infer that the 2‐gene signature might be a potential prognostic marker in patients with UPS/MFS. Considering the potential benefits of immunotherapy for UPS/MFS patients, it is imperative to explore the predictive value of this signature in immunotherapeutic responses in the future.

Using publically available datasets on gene expression in medulloblastoma (MB) subtypes, we selected genes for ubiquitin ligases and identified statistically those that best predicted each of the four major MB subgroups as separate disease entities. We identify a gene coding for an ubiquitin ligase, ZNRF3, whose overexpression alone can predict the WNT subgroup for 100% in the Pfister dataset. For the SHH subgroup, we identify a gene for a regulatory subunit of the protein phosphatase 2A (PP2A), PPP2R2C, as the major predictor among the E3 ligases genes. The ubiquitin and ubiquitin-like conjugation database (UUCD) lists PPP2R2C as coding for a Cullin Ring ubiquitin ligase adaptor. For group 3 MBs, the best ubiquitin ligase predictor was PPP2R2B, a gene which codes for another regulatory subunit of the PP2A holoenzyme. For group 4, the best E3 gene predictors were MID2, ZBTB18, and PPP2R2A, which codes for a third PP2A regulatory subunit. Heatmap analysis of the E3 gene data shows that expression of ten genes for ubiquitin ligases can be used to classify MBs into the four major consensus subgroups. This was illustrated by analysis of gene expression of ubiquitin ligases of the Pfister dataset and confirmed in the dataset of Cavalli. We conclude that genes for ubiquitin ligases can be used as genetic markers for MB subtypes and that the proteins coded for by these genes should be investigated as subtype specific therapeutic targets for MB.

Neuroendocrine tumor (NET) is one of malignant cancer and is identified with high morbidity and mortality rates around the world. With indigent clinical outcomes, potential biomarkers for diagnosis, prognosis and drug target are crucial to explore. The aim of this study is to examine the gene expression module of NET and to identify potential diagnostic and prognostic biomarkers as well as to find out new drug target. The differentially expressed genes (DEGs) identified from GSE65286 dataset was used for pathway enrichment analyses and gene ontology (GO) enrichment analyses and protein - protein interaction (PPI) analysis and module analysis. Moreover, miRNAs and transcription factors (TFs) that regulated the up and down regulated genes were predicted. Furthermore, validation of hub genes was performed. Finally, molecular docking studies were performed. DEGs were identified, including 453 down regulated and 459 up regulated genes. Pathway and GO enrichment analysis revealed that DEGs were enriched in sucrose degradation, creatine biosynthesis, anion transport and modulation of chemical synaptic transmission. Important hub genes and target genes were identified through PPI network, modules, target gene - miRNA network and target gene - TF network. Finally, survival analyses, receiver operating characteristic (ROC) curve and RT-PCR validated the significant difference of ATP1A1, LGALS3, LDHA, SYK, VDR, OBSL1, KRT40, WWOX, NINL and PPP2R2B between metastatic NET and normal controls. In conclusion, the DEGs and hub genes with their regulatory elements identified in this study will help us understand the molecular mechanisms underlying NET and provide candidate targets for future research.

PURPOSE: Investigate single nucleotide variants and short tandem repeats in 44 genes related to spinocerebellar ataxia in clinical and pathologically defined cohorts of multiple system atrophy. METHODS: Exome sequencing was conducted in 28 clinical multiple system atrophy patients to identify single nucleotide variants in spinocerebellar ataxia -related genes. Novel variants were validated in two independent disease cohorts, 86 clinically diagnosed multiple system atrophy patients and 166 pathological multiple system atrophy cases. Expanded repeat alleles in spinocerebellar ataxia genes were evaluated in 36 clinically diagnosed multiple system atrophy patients; CAG/CAA repeats in TATA-Box Binding Protein (TBP, causative of SCA17) were screened in 216 clinical and pathological multiple system atrophy patients and 346 controls. RESULTS: No known pathogenic spinocerebellar ataxia single nucleotide variants or pathogenic range expanded repeat alleles of ATXN1, ATXN2, ATXN3, CACNA1A, AXTN7, ATXN8OS, ATXN10, PPP2R2B, and TBP were detected in any clinical multiple system atrophy patients. However, four novel variants were identified in four spinocerebellar ataxia-related genes across three multiple system atrophy patients. Additionally, four multiple system atrophy patients (1.6%) and one control (0.3%) carried an intermediate length 41 TBP CAG/CAA repeat allele (OR=4.11, P=0.21). There was a significant association between occurrence of a repeat length of longer alleles (>38 repeats) and an increased risk of multiple system atrophy (OR=1.64, P=0.03). CONCLUSION: Occurrence of TBP CAG/CAA repeat length of longer alleles (>38 repeats) is significantly associated with increased multiple system atrophy risk. This discovery warrants further investigation and supports a possible genetic overlap of multiple system atrophy with SCA17.

Highlights In the current review, we thoroughly reviewed 74 identified articles regarding genes and genetic loci that confer susceptibility to ET. Over 50 genes/genetic loci have been examined for possible association with ET, but consistent results failed to be reported raising the need for collaborative multiethnic studies. Background: Essential tremor (ET) is a common movement disorder, which is mainly characterized by bilateral tremor (postural and/or kinetic) in the upper limbs, with other parts of the body possibly involved. While the pathophysiology of ET is still unclear, there is accumulating evidence indicating that genetic variability may be heavily involved in ET pathogenesis. This review focuses on the role of genetic risk factors in ET susceptibility. Methods: The PubMed database was searched for articles written in English, for studies with humans with ET, controls without ET, and genetic variants. The terms “essential tremor” and “polymorphism” (as free words) were used during search. We also performed meta-analyses for the most examined genetic variants. Results: Seventy four articles concerning LINGO1, LINGO2, LINGO4, SLC1A2, STK32B, PPARGC1A, CTNNA3, DRD3, ALAD, VDR, HMOX1, HMOX2, LRRK1,LRRK2, GBA, SNCA, MAPT, FUS, CYPsIL17A, IL1B, NOS1, ADH1B, TREM2, RIT2, HNMT, MTHFR, PPP2R2B, GSTP1, PON1, GABA receptors and GABA transporter, HS1BP3, ADH2, hSKCa3 and CACNL1A4 genes, and ETM genetic loci were included in the current review. Results from meta-analyses revealed a marginal association for the STK32B rs10937625 and a marginal trend for association (in sensitivity analysis) for the LINGO1 rs9652490, with ET. Discussion: Quite a few variants have been examined for their possible association with ET. LINGO1 rs9652490 and STK32B rs10937625 appear to influence, to some extent, ET susceptibility. However, the conflicting results and the lack of replication for many candidate genes raise the need for collaborative multiethnic studies.

Spinocerebellar ataxia type-12 (SCA12) is a neurological disorder caused due to triplet (CAG) repeat expansion in 5' UTR of PPP2R2B. It is one of the most prominent SCA-subtype in Indian population and till date no patient specific models have been described. Human-induced-pluripotent-stem cell (HiPSC) based disease modelling has become the next generation tool for studying various human pathologies. In the present study we established three SCA12 patient specific iPSC lines. All the generated lines have shown pluripotency markers, normal karyotype, in-vitro three germ layers differentiation potential, vector clearance, SCA12 mutation, parental genomic identity and contamination free culture.

Spinocerebellar ataxia type 12 (SCA12) is caused by a CAG expansion mutation in PPP2R2B, a gene encoding a brain-specific regulatory unit of protein phosphatase 2A (PP2A); while normal alleles carry 4 to 31 triplets, the disease alleles carry 43 to 78 triplets. Here, by CRISPR/Cas9 genome editing, we have generated a human homozygous SCA12 iPSC line with 69 and 72 triplets for each allele. The homozygous SCA12 iPSCs have normal karyotype, express pluripotency markers and are able to differentiate into the three germ layers.

Background Different gene expression profiles are observed in intracranial aneurysm tissue. Understanding these genes and what regulates their expression will help us to understand intracranial aneurysm pathogenesis. We investigated whether differences in gene expression in intracranial aneurysms. Methods Sixteen intracranial aneurysm tissues were compared with 16 matched samples from the superficial temporal artery as controls. We detected the gene expression profiles in these samples with the Human U133 Plus 2.0 GeneChip. Results A total of 2142 differentially expressed gene transcripts were detected based on the gene expression profile. Verification analysis showed that the VCAM1, MAGI2, PPP2R2B, PPP2R3A genes were associated with the occurrence and development of intracranial aneurysm. These genes mainly encode cell adhesion molecules (CAMs) and ERK/JNK signaling pathways. Conclusion Changes of genes expression involved in immune and inflammatory reactions, cell adhesion molecules may be associated with the development of aneurysms.

The present study describes the effects and mechanism of GA-13315 on the proliferation and apoptosis of KB cells in oral cancer. Oral cancer is twice as common in men than women. More than 90% of oral cancers in men and 85% in women are linked to lifestyle and environmental factors. PPP2R2B methylation may be associated with survival and prognosis in patients with gliomas. In tumor cell proliferation and apoptosis, the mechanism of PPP2R2B remains unclear. In the present study, we found that PPP2R2B expression of H1299 cells is significantly decreased after being treated by GA-13315. KB cells were isolated from patients with oral cancer and treated with GA-13315 (5 µM). Cells without GA-13315 treatment served as the control group. An MTT experiment was performed to detect the post-treatment cell growth between the groups. A flow cytometry was used to detect cell apoptosis. Western blot analysis and quantitative polymerase chain reaction methods were used for detecting the expression of PPP2R2B. Compared with the control group, the cell proliferation of the treatment group slowed after being treated with GA-13315. The difference was statistically significant (P

Background and Objectives Many hereditary movement disorders with complex phenotypes without a locus symbol prefix for familial PD present as parkinsonism; however, the dysregulation of genes associated with these phenotypes in the SNpc of PD patients has not been systematically studied. Methods Gene set enrichment analyses were performed using 10 previously published genome-wide expression datasets obtained by laser-captured microdissection of pigmented neurons in the SNpc. A custom-curated gene set for hereditary parkinsonism consisting of causative genes (n = 78) related to disorders with a parkinsonism phenotype, but not necessarily idiopathic or monogenic PD, was constructed from the Online Mendelian Inheritance in Man database. Results In 9 of the 10 gene expression data sets, gene set enrichment analysis showed that the disease-causing genes for hereditary parkinsonism were downregulated in the SNpc in PD patients compared to controls (nominal P values

Spinocerebellar ataxia type 12 (SCA12) is a rare neurodegenerative disorder caused by CAG repeat expansion in the PPP2R2B gene. Previously, the causal length of CAG repeats ascribed to SCA12 was more than 51; however, a few reports have also described unusual occurrence of CAG repeat length 36–51 repeats among patients of different geographical population, with atypical clinical association. From our systematic search for SCA12 in a genetic screening programme, we have identified a large number of SCA12 cases. In this study, we specifically describe the clinical behaviour of 18 patients who harbour CAG repeats in the range of 43–50 and compare their clinical behaviour with patients carrying typical pathogenic threshold length of 51 CAG repeats. Unsurprisingly, we observed that the clinical characteristics were similar to those of typical SCA12 phenotype, with large variability in the age at onset. Radiologically, we observed a variable degree of cerebro-cerebellar degeneration along with white matter changes that do not correlate with the disease severity. We define a new pathogenic threshold of CAG-43 to be pathogenic for SCA12 diagnosis and also describe the clinical profiles of two biallelic CAG expansion carriers. We also propose that SCA12 might not be that restricted in terms of occurrence in other geographical or ethnic populations, as it was previously presumed to be. * Abbreviations : ICARS = : International Cooperative Ataxia Rating Scale IpA = : intermediate pathogenic CAG alleles (43–50) PA = : typical pathogenic length of CAG alleles (51) SCA12 = : spinocerebellar ataxia type 12

Introduction Huntington’s disease (HD) is an autosomal dominant neurodegenerative disease, caused by the expansion of a CAG repeat within exon 1 of IT15 gene. HD exhibits the typical phenomenon of genetic anticipation and the symptoms of the disease appear earlier and more severe in subsequent generations due to meiotic instability. The CAG repeat accounts only for approximately 56%–70% of the variation in age at onset in HD. It is likely that modifying genetic variations, which segregate independently from the primary mutation, could influence the age at onset. Aims of the study Genetic, pathological, and clinical similarities exist between HD and spino-cerebellar ataxias (SCAs). In this study, seven SCAs genes have been studied as modifiers of age at onset in a cohort of HD patients. Materials and Methods We enrolled 50 HD patients. For every HD subject, CAG repeats have been measured on the larger allele of ATXN1, ATXN2, ATXN3, CACNA1A, ATXN7, PPP2R2B, and TBP genes. Regression analysis was used to evaluate the effects of CAG repeats in SCAs genes on age at motor, cognitive and psychiatric onset in HD patients. Results We did not find extensive correlations between CAG repeats in SCA genes and age at onset of HD. The only exceptions were represented by ATXN2 and CACNA1 genes for age at motor onset, and ATXN2 for age at psychiatric onset. When a multiple regression model was tested, a small additional effect on age at motor onset was identified only for CACNA1A. CAG repeats in expanded HD gene and larger CACNA1A alleles account for 64% of age at motor onset in HD patients. Conclusions CACNA1A gene could represent a mild genetic modifier of age at onset in HD patients. Further studies, conducted on larger HD patients‘ cohorts, are needed to confirm our data.

To investigate the association of repeat expansion size in 10 common degenerative hereditary ataxia genes with essential tremor. These genes were spinocerebellar ataxia (SCA)-1 (ATXN1), SCA-2 (ATXN2), SCA-3 (ATXN3), SCA-6 (CACNA1A), SCA-7 (ATXN7), SCA-8 (ATXN8OS), SCA-10 (ATXN10), SCA-12 (PPP2R2B), SCA-17 (TBP) and dentatorubral-pallidolysian atrophy (DRPLA) (ATN1).Genetic analysis of repeat size in 10 degenerative hereditary ataxia loci was performed in 323 essential tremor patients and 299 controls enrolled at Columbia University. To test for differences in the allele distribution between patients and controls, a CLUMP analysis was performed.None of the essential tremor patients had a repeat expansion in the intermediate or pathogenic range. Significant differences in the distribution of repeats in the 'normal' range for SCA2 and SCA8 (both p ≤ 0.02) were observed between essential tremor patients and controls.Our study suggests that pathogenic repeat expansions in SCA loci are not associated with essential tremor.

Spinocerebellar ataxia type-12 (SCA12) is a neurological disorder that exhibits a unique progressive tremor/ataxia syndrome induced by triplet (CAG) repeat expansion in 5’ UTR of PPP2R2B. SCA12 is one of the most prominent SCA-subtype in India and till date no appropriate disease models have been described. Our aim was to establish human iPSC derived neuronal cell lines of SCA12 and study transcriptomic level alterations induced by CAG expansion. For translational application, peripheral blood transcriptomics of SCA12 patients was also performed. Lymphoblastoid cell lines of three SCA12 patients were reprogrammed to iPSCs and then re-differentiated into pan-neuronal lineage. RNA-sequencing based comparative transcriptomics was performed for disease and control cell lineages. Microarray based transcriptomic profiling of peripheral blood of SCA12 patients was performed in a case/control (n=15/9) design. We have successfully created human neuronal cell lines of SCA12 patient as exhibited by their molecular profiling. Differential expression analysis of RNA-Seq data has shown enrichment for type-I interferon signaling and other relevant cellular processes in SCA12-neurons. At the splice-isoform level, we observed an upregulation of expanded CAG containing non-coding transcript of PPP2R2B. Peripheral blood transcriptomics analysis and targeted validation of RNA-Seq data has allowed us to identify inflammatory signatures as potential markers of molecular pathology in SCA12. Our study has allowed us to establish first iPSC based neuronal cell lines of SCA12. We have identified pro-inflammatory signatures in SCA12-neurons suggestive of a dsRNA mediated activation of interferon signaling and that corroborates with the emerging evidence of neuronal atrophy due to neuro-inflammation in common neurodegenerative diseases. This study involved development of an iPSCs derived neuronal cells of SCA12 and look through signatures of neurodegeneration by whole RNA sequencing. This model sheds light upon key role of RNA mediated induced response in Interferon signaling for neurodegeneration.

Spinocerebellar ataxia type 12 (SCA12) is a rare autosomal dominant neurodegenerative disease characterized by tremor, gait abnormalities, and neuropsychiatric syndromes. The location of the causative CAG/CTG expansion mutation in PPP2R2B, a gene encoding regulatory units of the protein phosphatase 2A, may provide unique insights into the pathogenesis of neurodegeneration.The first neuropathological examination of a brain from an SCA12 patient revealed both cerebellar and cerebral cortical atrophy, with a noted loss of Purkinje cells and no evidence of polyglutamine aggregates. Molecular investigations have demonstrated considerable complexity of PPP2R2B, which appears to encode at least eight isoforms each with a different N-terminal region. The repeat potentially influences PPP2R2B expression, and is itself included in several splice variants, falling within an open reading frame of at least one of these variants.The current data suggest at least two nonmutually exclusive hypotheses of SCA12 neurodegeneration. First, the repeat may influence PPP2R2B expression, by altering promoter activity, splicing, or transcript stability. This hypothesis would predict that the mutation changes the regulation of protein phosphatase 2A, with implications for the phosphoproteome. Alternatively, the repeat itself may be expressed and have toxic properties, though perhaps not through polyglutamine tracts. Either hypothesis may provide novel insight into the pathogenesis of neurodegeneration.

Spinocerebellar ataxia type 12 (SCA12) is a progressive neurological disorder with a unique prevalence in North Indian population. Trinucleotide CAG repeat expansion beyond certain threshold (>43 repeats) in the upstream region of PPP2R2B gene is associated with cerebello-cortical atrophy in disease affected individuals. Patients with SCA12 predominantly manifest unique distinguishable feature of early slow and progressive action tremor in upper extremities followed by other variable symptoms such as mild to moderate gait ataxia, speech disturbances with tremulous voice, head tremor, and autonomic abnormalities. At present, there is no definite treatment available to cure this disease and the underlying disease mechanism at molecular level largely remains undetermined. This review focuses on epidemiology, clinico-genetic advancements, and therapeutics interventions emerged over the time in this field.

In a Chinese family with Spinocerebellar ataxia type 12 (SCA12), presenting with action tremor, mild cerebellar dysfunction, and hyperreflexia, genetic testing revealed abnormal CAG repeat length in the brain-specific protein phosphatase 2, regulatory subunit B, beta isoform (PPP2R2B) gene. To our knowledge, this is the first report on patients with SCA12 presenting with prominent cerebral white matter change besides cerebral and/or cerebellar atrophy.

Computational prediction of biological networks would be a tremendous asset to systems biology and personalized medicine. In this paper, we use a moving window bioinformatic screen to identify transcripts with partial identity to the 5′ and 3′UTRs of the polyQ spinocerebellar ataxia (SCA) genes ATXN1, ATXN2, ATXN3, ATXN7, TBP and CACNA1A and the CAG repeat expansion gene PPP2R2B. We find that the bioinformatic screen enriches for transcripts that encode proteins that interact and that have functions relevant to polyQ SCA. Transcription control and RNA binding are the primary functional groups represented in the proteins from the combined screens. The insulin growth factor pathway, the WNT pathway, long term potentiation, melanogenesis and ATM mediated DNA repair pathways were identified as important pathways. UGUUU repeats were identified as an abundant motif in the SCA network and PAXIP1, CELF2, CREBBP, EBF1, PLEKHG4, SRSF4, C5orf42, NFIA, STK24, and YWHAG were identified as statistically significant proteins in the polyQ and PPP2R2B network.

// Yihao Yang 1, * , Ya Zhang 1, * , Xin Qu 1, * , Junfeng Xia 1 , Dongqi Li 1 , Xiaojuan Li 1 , Yu Wang 1 , Zewei He 1 , Su Li 1 , Yonghong Zhou 1 , Lin Xie 1, * , Zuozhang Yang 1, * 1 Bone and Soft Tissue Tumors Research Center of Yunnan Province, Department of Orthopaedics, The Third Affiliated Hospital of Kunming Medical University (Tumor Hospital of Yunnan Province), Kunming, Yunnan 650118, China * These authors contributed equally to this work and co-first authors Correspondence to: Zuozhang Yang, email: yangzuozhang@163.com , zuozhangyang1326@sohu.com Lin Xie, email: xielinyanghan@163.com Keywords: differentially expressed genes, network, primary osteosarcoma, metastatic osteosarcoma, target Received: August 15, 2016 Accepted: November 07, 2016 Published: November 24, 2016 ABSTRACT Objective: Osteosarcoma (OS) is a malignant bone tumor with high morbidity in young adults and adolescents. This study aimed to discover potential early diagnosis biomarkers in OS. Results: In total, 111 differentially expressed genes (DEGs) were identified in primary OS compared with normal controls and 235 DEGs were identified in metastatic OS compared with primary OS. AURKB and PPP2R2B were the significantly up-regulated and down-regulated hub proteins, respectively, in the PPI protein-protein network (PPI) network of primary OS. ISG15 and BTRC were the significantly up-regulated and down-regulated hub proteins, respectively, in the network of metastatic OS. The DEGs in metastatic OS compared with primary OS were significantly enriched in the arachidonic acid metabolism, malaria, and chemokine signaling pathways. Finally, we employed quantitative real-time polymerase chain reaction (qRT-PCR) to validate the expression levels of candidate DEGs and the results indicated that our bioinformatics approach was acceptable. Materials and Methods: The mRNA expression profiling of 20 subjects was obtained through high-throughput RNA-sequencing. DEGs were identified between primary OS and normal Control, and between primary OS and metastatic OS, respectively. Functional annotation and PPI networks were used to obtain insights into the functions of DEGs. qRT-PCR was performed to detect the expression levels of dysregulated genes in OS. Conclusions: Our work might provide groundwork for the further exploration of tumorigenesis and metastasis mechanisms of OS.

Background Osteogenesis imperfecta (OI) is a group of hereditary disorders characterized by low bone mass and recurrent fractures. Most OI cases follow an autosomal dominant pattern of inheritance and are attributed to mutations in genes encoding type I collagen ( COL1A1 / COL1A2 ). Genomic structural variations involving type I collagen genes are extremely rare in OI. Case report In this study, we characterized a de novo balanced translocation of t(5;7)(q32;q21.3) that caused an extremely rare type of OI in a patient from a non-consanguineous family. The clinical phenotypes of this OI included recurrent fractures, low bone mass, macrocephaly, blue sclera and failure to thrive. Next-generation sequencing was used to identify the translocation, and Sanger sequencing was used to validate and map the breakpoints. The breakpoint on chromosome 7 disrupted the COL1A2 gene in the 17th exon, presumed to affect type I collagen production and give rise to OI. The breakpoint on chromosome 5 disrupted the protein phosphatase 2 regulatory subunit B, beta gene ( PPP2R2B ) within the first intron. Conclusions This is the first report of a copy-neutral structural variant involving COL1A2 that leads to a rare type of OI. This study expands the genotypic spectrum of OI and demonstrates the effectiveness of targeted sequencing for breakpoint mapping.

Spinocerebellar ataxia 12 (SCA12) is a unique dominant type of ataxia characterized by early and prominent action tremors, memory deficit, neuropathy, dysarthria, etc. The expansion of DNA triplet (CAG) repeats in 5'UTR of PPP2R2B gene appears to be the cause for the pathogenesis of the neurodegenerative disorder, SCA12. The objective of the current study was to identify the aberrantly expressed plasma proteins for their potential application in therapy or diagnosis/prognosis of SCA12. Sixty-two clinically suspected patients were assessed using International Co-operative Ataxia Rating Scale (ICARS) and genetic confirmation was done using PCR followed by DNA sequencing. Twenty patients who were genetically confirmed were included in the study. 2D-DIGE analyses of plasma proteins of SCA12 patients revealed 14 differentially expressed protein spots, which were confirmed as nine proteins by LC-MS/MS. The 6 downregulated and 3 upregulated proteins are known to have physiological role in transport (thyroxin and retinol to brain), lipid metabolism, memory, scavenging of free haemoglobin, etc. Altered expression of some of the proteins of interest, transthyretin, haptaglobin, apolipoprotein C-II, apolipoprotein C-III are indicative of clinical manifestations such as neuropathy, cognitive impairment and altered lipid metabolism in SCA12.

We analyzed the association between PPP2R2B gene CAG repeat length and Alzheimer disease (AD) susceptibility in the Japanese population. Blood samples were collected from 218 late-onset AD patients and 86 controls. DNA fragments containing the target CAG repeat region were amplified using polymerase chain reaction (PCR). PCR products were sequenced using ABI PRISM 310 genetic analyzer. The mean CAG repeat length did not differ significantly between the control and AD groups. In contrast, the frequency of CAG repeats shorter than 15 was significantly higher in AD group, specifically in the AD with APOE4 subgroup, than in the control group. The results suggest that CAG repeat lengths in the PPP2R2B gene may be potential genetic markers for AD susceptibility in the Japanese population.

PPP2R2B, a protein widely expressed in neurons, regulates the protein phosphatase 2A (PP2A) activity for dephosphorylation of tau and other substrates. CAG repeat expansion at the 5'-end of the PPP2R2B gene causes autosomal dominant spinocerebellar ataxia type 12. In the present study, we investigated the roles of CAG repeats and flanking cis elements and the associated proteins in controlling PPP2R2B expression. Deletion/site-directed mutagenesis, in silico searches and cDNA overexpression revealed that CREB1 and SP1 bind to the conserved sequence upstream the CAG repeats to up-regulate PPP2R2B expression, whereas TFAP4 binds to the conserved sequence downstream the CAG repeats to down-regulate PPP2R2B expression. The binding of CREB1, SP1, and TFAP4 to the PPP2R2B promoter was further confirmed by DNA pull-down and ChIP-PCR assays. CAG repeats itself also function as a cis element to up-regulate PPP2R2B expression as AT repeat length has no effect on PPP2R2B expression. Together, our data provide evidence that CREB1, SP1, and TFAP4 play roles in modulating PPP2R2B expression, thus offering a mechanism of regulating PP2A activity as the treatment of neurodegenerative diseases associated with abnormal PP2A activity.

Background: Protein phosphatase 2A (PP2A) has been implicated in radiation-induced activation of cellular responses, likely by its ability to regulate the autophosphorylation of the ataxia telangiectasia mutated (ATM) protein, a key molecule involved in the DNA damage response initiated by double-stranded DNA breaks. Interestingly, a hereditary defect in the PPP2R2B gene, which encodes the beta isoform of PP2A regulatory subunit B, causes autosomal dominant spinocerebellar ataxia 12, a clinical condition resembling that of ataxia telangiectasia patients. Moreover, PPP2R2B is significantly down-regulated in many human cancers, including head and neck squamous cell carcinomas (HNSCCs). Objective: Examine whether PPP2R2B regulates ATM function, thereby contributing to tumor progression due to the resulting defective DNA repair. Methods: The roles of PPP2R2B were evaluated in irradiated HNSCC cell lines, siRNAPPP2R2B cells and okadaic acid treated cells. Expression of PPP2R2B was measured by microarray, Western blot analysis and real time quantitative rtPCR. ATM quantity and localization, ATM phosphorylation and γ-H2AX were determined by Western blot analysis and/or immunofluorescence assay. Clonogenic cell survival assay was performed to determine ionizing radiation sensitivity. Results: PPP2R2B expression is reduced in multiple tumor types, including HNSCCs. Indeed, HNSCC cell lines that have lower PPP2R2B mRNA expression and siRNAPPP2R2B cells lower basal and radiation-induced levels of phosphorylated ATM and the consequent reduction in the levels of phosphorylation of the downstream ATM target, γ-H2AX. Depletion of PPP2R2B and inhibition of PP2A with okadaic acid resulted in limited ATM nuclear localization. Finally, siRNAPPP2R2B cells displayed enhanced sensitivity to death after radiation. Conclusion: In HNSCCs, ATM nuclear localization is PPP2R2B dependent, and decreased PPP2R2B expression may result in limited ATM activation by preventing its nuclear accumulation and ATM-chromatin interaction. Therefore, decreased PPP2R2B expression in HNSCCs may contribute to genomic instability, cancer development and radiation sensitivity by limiting ATM functions.

The deregulation of Wnt signaling is observed in various cancers, including gliomas, and might be related to the methylation of the genes encoding antagonists of this signaling pathway. The aim of the study was to assess the methylation status of the promoter regions of six Wnt negative regulators and to determine their prognostic value in clinical samples of gliomas of different grades. The methylation of SFRP1, SFRP2, PPP2R2B, DKK1, SOX17, and DACH1 was analyzed in 64 glioma samples using methylation-specific polymerase chain reaction (MSP). The results were analyzed in correlation with clinicopathological data. Promoter methylation in at least one of the analyzed genes was found in 81.3 % of the tumors. All benign tumors [grade I according to the World Health Organization (WHO) classification] lacked the methylation of the studied genes, whereas grade II, III, and IV tumors were, in most cases, methylation-positive. The methylation index correlated with the patient’s age. The most frequently methylated genes were SFRP1 and SFRP2 (73.4 % and 46.9 %, respectively), followed by SOX17 (20.3 %) and PPP2R2B (10.9 %); DKK1 and DACH1 were basically unmethylated (1.6 %). SFRP1 methylation negatively correlated with patients’ survival time, and was significantly more frequent in older patients and those with higher grade tumors. Overall, the results of this study indicate that aberrant promoter methylation of Wnt pathway antagonists is common in gliomas, which may be the possible cause of up-regulation of this signaling pathway often observed in these tumors. Moreover, SFRP1 promoter methylation can be regarded as a potential indicator of glioma patients’ survival.

Spinocerebellar ataxia type 12 (SCA12) is an autosomal dominant cerebellar ataxia associated with the expansion of an unstable CAG repeat in the 5' region of the PPP2R2B gene on chromosome 5q31-5q32. We found that it accounts for approximately 16% (20/124) of all the autosomal dominant ataxia cases diagnosed in AIIMS, a major tertiary referral centre in North India. The length of the expanded allele in this population ranges from 51-69 CAG triplets. Interestingly, all the affected families belong to an endogamous population, which originated in the state of Haryana, India. We identified four novel SNPs and a dinucleotide marker spanning approximately 137 kb downstream of CAG repeat in the PPP2R2B gene. Analysis of 20 Indian SCA12 families and ethnically matched normal unrelated individuals revealed one haplotype to be significantly associated with the affected alleles (P= 0.000), clearly indicating the presence of a common founder for SCA12 in the Indian population. This haplotype was not shared by the American pedigree with SCA12. Therefore, the SCA12 expansion appears to have originated at least twice.

Spinocerebellar ataxia type 12 (SCA12), now described in European-American and Asian (Indian) pedigrees, is unique among the SCAs from clinical, pathological, and molecular perspectives. Clinically, the distinguishing feature is early and prominent action tremor with variability in other signs. Pathologically, brain MRIs also suggest variability, with promi- nent cortical as well as cerebellar atrophy. Genetically, SCA12 is caused by a CAG repeat expansion that does not encode polyglutamine; we speculate that the mutation may affect expression of the gene PPP2R2B, which encodes a brain-specific regulatory subunit of the protein phosphatase PP2A.

Background Spinocerebellar ataxia type 12 (SCA12) is predominantly characterized by action tremor, followed by slowly progressive cerebellar dysfunction. It is a very rare disorder and only identified in certain countries so far. The current appreciation for phenotypic and genotypic features of SCA12 is still limited. Methods We investigated CAG copies within PPP2R2B in 29 patients with spinocerebellar ataxia who are excluded from the most common SCA subtypes including SCA1, SCA2, SCA3 and SCA6. The medical data of patients carrying abnormal expanded PPP2R2B allele were reviewed and summarized. Results We found that 3 patients carried 53, 46 and 54 CAG repeats respectively, while the other 26 cases harbored CAG repeats less than 30. The probably shortest pathogenic allele of 46 repeats was detected in one kindred typically experiencing action tremor. Additionally, compared to the prominent cerebellar ataxia, nystagmus and dysphagia seem to be rare in our SCA12 patients. Conclusions SCA12 might not be as rare in Chinese as previously assumed. The identification of the shortest pathogenic allele helps to define the minimal limit implicated in the disease onset. Moreover, the disease manifestations distinct from other SCA subtypes could help clinicians to provide timely genetic counseling.

Spinocerebellar ataxia 12 (SCA12) is an autosomal dominant cerebellar ataxia (ADCA) described in a single family with a CAG repeat expansion in the PPP2R2B gene. We screened 247 index cases, including 145 families with ADCA, for this expansion. An expanded repeat ranging from 55 to 61 triplets was detected in 6 affected and 3 unaffected individuals at risk in a single family from India. The association of the PPP2R2B CAG repeat expansion with disease in this new family provides additional evidence that the mutation is causative.

Aging is thought to occur through the accumulation of molecular and cellular damage. A key regulator of the cell's stress response is p53. In mice, the activity of p53 associates with lifespan. We were therefore interested whether SNPs in members of the p53-pathway are associated with longevity in humans. We genotyped the following SNPs: p53 - rs1042522 (Arg72Pro), MDM2 - rs2279744 (SNP309), MDM4 - rs4245739 (SNP34091), rs1563828 (SNP31826), PPP2R2B (rs319217) in 155 long-lived individuals (LLIs) who died at the age of 91 and over and in 171 ethnically-matched control subjects. Kaplan-Meier survival curves and log-Rank-test were used to determine the mean and median survival times. In female LLIs, the Pro-allele of rs1042522 (Arg72Pro) and the G-allele of rs2279744 (SNP309) were significantly associated with an increased survival time (P=0.026, P

Spinocerebellar Ataxia 12 (SCA12) is a rare disease that was first identified in a family in the United States. Patients suffered from classical spinocerebellar ataxia symptoms with an age of disease onset ranging from 8-55 years. A trinucleotide (CAG) repeat expansion was confirmed in all the affected individuals. The CAG expansion mapped to the 5’ untranslated region (UTR) of the PPP2R2B gene. This gene encodes a regulatory subunit, B of the heterotrimeric protein phosphatase 2A (PP2A). The function of this particular PP2A complex is not well understood, and the underlying molecular mechanism of SCA12 remains unclear. Additional pedigrees have been identified throughout the world but SCA12 remains a rare disease. In this chapter we will discuss the clinical manifestation of the disease and the known functions of the PP2A regulator B.