Search

The congenital intellectual disability (ID)-causing gene mutations remain largely unclear, although many genetic variations might relate to ID. We screened gene mutations in Chinese Han children suffering from severe ID and found a single-nucleotide polymorphism (SNP) in the 5′-untranslated region (5′-UTR) of fibroblast growth factor 13 (FGF13) mRNA (NM_001139500.1:c.-32c>G) shared by three male children. In both HEK293 cells and patient-derived induced pluripotent stem cells, this SNP reduced the translation of FGF13, which stabilizes microtubules in developing neurons. Mice carrying the homologous point mutation in 5′-UTR of Fgf13 showed delayed neuronal migration during cortical development, and weakened learning and memory. Furthermore, this SNP reduced the interaction between FGF13 5′-UTR and polypyrimidine-tract-binding protein 2 (PTBP2), which was required for FGF13 translation in cortical neurons. Thus, this 5′-UTR SNP of FGF13 interferes with the translational process of FGF13 and causes deficits in brain development and cognitive functions.

The congenital intellectual disability (ID)-causing gene mutations remain largely unclear, although many genetic variations might relate to ID. We screened gene mutations in Chinese Han children suffering from severe ID and found a single-nucleotide polymorphism (SNP) in the 5′-untranslated region (5′-UTR) of fibroblast growth factor 13 (FGF13) mRNA (NM_001139500.1:c.-32c>G) shared by three male children. In both HEK293 cells and patient-derived induced pluripotent stem cells, this SNP reduced the translation of FGF13, which stabilizes microtubules in developing neurons. Mice carrying the homologous point mutation in 5′-UTR of Fgf13 showed delayed neuronal migration during cortical development, and weakened learning and memory. Furthermore, this SNP reduced the interaction between FGF13 5′-UTR and polypyrimidine-tract-binding protein 2 (PTBP2), which was required for FGF13 translation in cortical neurons. Thus, this 5′-UTR SNP of FGF13 interferes with the translational process of FGF13 and causes deficits in brain development and cognitive functions.

Cancer is an extremely diverse and complex disease that results from various genetic and epigenetic changes such as DNA copy-number variations, mutations, and aberrant mRNA and/or protein expression caused by abnormal transcriptional regulation. The expression profiles of certain microRNAs (miRNAs) and messenger RNAs (mRNAs) are closely related to cancer progression stages. In the past few decades, DNA microarray and next-generation sequencing techniques have been widely applied to identify miRNA and mRNA signatures for cancers on a genome-wide scale and have provided meaningful insights into cancer diagnosis, prognosis and personalized medicine. In this review, we summarize the progress in genome-wide analysis of miRNAs and mRNAs as cancer biomarkers, highlighting their diagnostic and prognostic roles.

Sensory neurons are distinguished by distinct signaling networks and receptive characteristics. Thus, sensory neuron types can be defined by linking transcriptome-based neuron typing with the sensory phenotypes. Here we classify somatosensory neurons of the mouse dorsal root ganglion (DRG) by high-coverage single-cell RNA-sequencing (10 950 ± 1 218 genes per neuron) and neuron size-based hierarchical clustering. Moreover, single DRG neurons responding to cutaneous stimuli are recorded using an in vivo whole-cell patch clamp technique and classified by neuron-type genetic markers. Small diameter DRG neurons are classified into one type of low-threshold mechanoreceptor and five types of mechanoheat nociceptors (MHNs). Each of the MHN types is further categorized into two subtypes. Large DRG neurons are categorized into four types, including neurexophilin 1-expressing MHNs and mechanical nociceptors (MNs) expressing BAI1-associated protein 2-like 1 (Baiap2l1). Mechanoreceptors expressing trafficking protein particle complex 3-like and Baiap2l1-marked MNs are subdivided into two subtypes each. These results provide a new system for cataloging somatosensory neurons and their transcriptome databases.

SummaryExcitatory synaptic transmission is modulated by inhibitory neurotransmitters and neuromodulators. We found that the synaptic transmission of somatic sensory afferents can be rapidly regulated by a presynaptically secreted protein, follistatin-like 1 (FSTL1), which serves as a direct activator of Na+,K+-ATPase (NKA). The FSTL1 protein is highly expressed in small-diameter neurons of the dorsal root ganglion (DRG). It is transported to axon terminals via small translucent vesicles and secreted in both spontaneous and depolarization-induced manners. Biochemical assays showed that FSTL1 binds to the α1 subunit of NKA and elevates NKA activity. Extracellular FSTL1 induced membrane hyperpolarization in cultured cells and inhibited afferent synaptic transmission in spinal cord slices by activating NKA. Genetic deletion of FSTL1 in small DRG neurons of mice resulted in enhanced afferent synaptic transmission and sensory hypersensitivity, which could be reduced by intrathecally applied FSTL1 protein. Thus, FSTL1-dependent activation of NKA regulates the threshold of somatic sensation.

Lymphotoxin-alpha (LTA), a pro-inflammatory cytokine, has been implicated in the pathogenesis of coronary atherosclerosis. Meanwhile, association of some single nucleotide polymorphisms (SNPs) of LTA gene with coronary artery disease (CAD) has been evaluated; however, the results are irreproducible. We therefore investigated the relationship between four SNPs of LTA gene and CAD in Han Chinese: G+10A (rs1800683, 5'-untranslated region), A+80C (rs2239704, 5'-untranslated region), T+496C (Cys13Arg, rs2229094, exon 2), and C+804A (Thr26Asn, rs1041981, exon 3). Genotyping was performed in 438 CAD patients and 330 healthy controls. Single-locus analysis showed that the genotype and allele frequencies of G+10A polymorphism exhibited marginal differences between CAD patients and controls, although no statistical significance was observed after the Bonferroni correction. Logistic regression analysis revealed that GG genotype of G+10A polymorphism was significantly associated with the risk of CAD under the dominant mode, whereas no significant association was detected between A+80C polymorphism and CAD. In contrast, individuals carrying TT or TC genotype of T+496C polymorphism showed a decreased CAD risk relative to those with CC genotype under the recessive mode. Likewise, CC genotype of C+804A polymorphism was associated with a protective effect on CAD under the dominant mode. Further, in haplotype analysis, the haplotype G-C-T-C (in order of rs1800683, rs2239704, rs2229094 and rs1041981) was significantly associated with a decreased risk of CAD after assigning the most common haplotype A-C-T-A as a reference. In conclusion, we show a protective effect of the haplotype G-C-T-C on the occurrence of CAD, suggesting the involvement of LTA in CAD pathogenesis.

HYPB is a human histone H3 lysine 36 (H3K36)–specific methyltransferase and acts as the ortholog of yeast Set2. This study explored the physiological function of mammalian HYPB using knockout mice. Homozygous disruption of Hypb impaired H3K36 trimethylation but not mono- or dimethylation, and resulted in embryonic lethality at E10.5-E11.5. Severe vascular defects were observed in the Hypb −/− embryo, yolk sac, and placenta. The abnormally dilated capillaries in mutant embryos and yolk sacs could not be remodeled into large blood vessels or intricate networks, and the aberrantly rounded mesodermal cells exhibited weakened interaction with endothelial cells. The embryonic vessels failed to invade the labyrinthine layer of placenta, which impaired the embryonic–maternal vascular connection. These defects could not be rescued by wild-type tetraploid blastocysts, excluding the possibility that they were caused by the extraembryonic tissues. Consistent with these phenotypes, gene expression profiling in wild-type and Hypb −/− yolk sacs revealed that the Hypb disruption altered the expression of some genes involved in vascular remodeling. At the cellular level, Hypb −/− embryonic stem cell–derived embryonic bodies, as well as in vitro–cultured human endothelial cells with siRNA-mediated suppression of HYPB , showed obvious defects in cell migration and invasion during vessel formation, suggesting an intrinsic role of Hypb in vascular development. Taken together, these results indicate that Hypb is required for embryonic vascular remodeling and provide a tool to study the function of H3K36 methylation in vasculogenesis/angiogenesis.

The epigenetic silencing of tumor suppressor genes is a crucial event during carcinogenesis and metastasis. Here, in a human genome-wide survey, we identified scavenger receptor class A, member 5 (SCARA5) as a candidate tumor suppressor gene located on chromosome 8p. We found that SCARA5 expression was frequently downregulated as a result of promoter hypermethylation and allelic imbalance and was associated with vascular invasion in human hepatocellular carcinoma (HCC). Furthermore, SCARA5 knockdown via RNAi markedly enhanced HCC cell growth in vitro, colony formation in soft agar, and invasiveness, tumorigenicity, and lung metastasis in vivo. By contrast, SCARA5 overexpression suppressed these malignant behaviors. Interestingly, SCARA5 was found to physically associate with focal adhesion kinase (FAK) and inhibit the tyrosine phosphorylation cascade of the FAK-Src-Cas signaling pathway. Conversely, silencing SCARA5 stimulated the signaling pathway via increased phosphorylation of certain tyrosine residues of FAK, Src, and p130Cas; it was also associated with activation of MMP9, a tumor metastasis–associated enzyme. Taken together, these data suggest that the plasma membrane protein SCARA5 can contribute to HCC tumorigenesis and metastasis via activation of the FAK signaling pathway.

Investigation of DNA-protein interactions is fundamental to understand the mechanism underlying a variety of life processes. In this article, various types of biochemical methods in DNA-protein interaction study in vivo and in vitro at the level of DNA, protein, and the complex, respectively were briefly reviewed. Traditional assays including Nitrocellulose filter-binding assay, Footprinting, EMSA, and Southwestern blotting were summarized. In addition, chromatin immunopre-cipitation techniques including nChIP, xChIP, and ChIP-on-chip, which were widely used in epigenetics, were particularly introduced.

Drug resistance in Plasmodium falciparum is a serious public health threat in the countries where this organism is endemic. Since resistance has been associated with specific single-nucleotide polymorphisms (SNPs) in parasite genes, molecular markers are becoming useful surrogates for monitoring the emergence and dispersion of drug resistance. In this study, a multiplex PCR (mPCR) and oligonucleotide microarray method was developed for the detection of these SNPs in genes encoding chloroquine resistance transporter (Pf crt ), multidrug resistance 1 (Pf mdr1 ), dihydrofolate reductase (Pf dhfr ), dihydropteroate synthetase (Pf dhps ), and ATPase 6 (Pf ATPase6 ) of P. falciparum . The results show that DNA microarray technology, combined with mPCR, is a promising and time-saving tool that supports conventional detection methods, allowing sensitive, accurate, simultaneous analysis of the SNPs associated with drug resistance in P. falciparum .

OBJECTIVE: The expression of S100A6 (calcyclin), a member of the S100 calcium binding protein family, is elevated in a number of malignant tumors, but there have been few reports about its expression in gastric cancer. The aim of this study was to investigate its expression regulations in human gastric cancer and noncancerous mucosa, and the response to chemotherapeutic drugs in the gastric cancer cell line. MATERIALS AND METHODS: In one matched gastric cancer sample pair, the serial analysis of gene expression (SAGE) experiment was conducted to compare the gene expression profiles between cancerous and adjacent tissues. To detect the expression regulations among more cancerous tissues, microarrays were carried out and real-time RT-PCR was conducted to validate the results. At the protein level, Western blot and tissue microarray (TMA) examination were further used to verify S100A6 expression. The regulation detection of S100A6 with flurouracil and doxorubicin at the mRNA and protein level was performed in the SGC7901 cell line. RESULTS: With the SAGE strategy, five times more S100A6 tags were identified in cancer tissues than in normal tissues. With the cDNA microarray, S100A6 was found to be significantly upregulated in 21 of 42 (50%) nonselective gastric cancers. In 10 other paired samples, the upregulation of S100A6 was consolidated with RT-PCR and Western blot analysis as well. A total of 14 endoscopy-sectioned gastric noncancerous lesions and corresponding normal gastric mucosa were also applied to profile the gene expression; both cDNA microarray and RT-PCR demonstrated no significant alterations of S100A6 at the mRNA level. TMA examination showed that 34 of 52 (65.4%) cancer samples were positively stained, while only 17 of 80 (21.3%) noncancerous lesions were positively detected and all nine normal mucosae were detected to be negative. An in vitro experiment showed that in the gastric cell line SGC-7901, S100A6 mRNA was detected to be upregulated from 24 to 72 h after treatment with 5 mg/L 5flurouracil or 0.3 mg/L doxorubicin, and there were two wave upregulations of the S100A6 protein. CONCLUSION: The observed regulated expression of S100A6 suggests that it is associated with gastric cancer tumorigenesis and quantitation of S100A6 is a promising tool for diagnosis of gastric cancer.

Aim: The human cytochrome P450 2D6 (CYP2D6) gene copy number variation, involving CYP2D6 gene deletion (CYP2D6*5) and duplication or multiduplication (CYP2D6*×N), can result in reduced or increased metabolism of many clinically used drugs. The identification of CYP2D6*5 and CYP2D6*×N and the investigation of their allelic distributions in ethnic populations can be important in determining the right drug and dosage for each patient. Methods: The CYP2D6*5 and CYP2D6 genes, and CYP2D6 gene duplication were identified by 2 modified long PCR, respectively. To determine duplicated alleles, a novel long PCR was developed to amplify the entire duplicated CYP2D6 gene which was used as template for subsequent PCR amplification. A total of 363 unrelated Eastern Han Chinese individuals were analyzed for CYP2D6 gene copy number variation. Results: The frequency of CYP2D6*5 and CYP2D6*×N were 4.82% (n=35) and 0.69% (n=5) in the Eastern Han Chinese population, respectively. Of the 5 duplicated alleles, 3 were CYP2D6*1×N and 2 were CYP2D6*10×N. One individual was a carrier of both CYP2D6*5 and CYP2D6*1×N. Taken together, the CYP2D6 gene rearrangements were present in 10.74% of subjects. Conclusion: Allelic distributions of the CYP2D6 gene copy number variation differ among Chinese from different regions, indicating ethnic variety in Chinese. Long PCR are convenient, cost effective, specific and semiquantitative for the detection of the CYP2D6 gene copy number variation, and amplification of the entire duplicated CYP2D6 gene is necessary for the accurate identification of duplicated alleles.

Objects Our objective was to develop an oligonucleotide DNA microarray (OMA) for genome-wide microRNA profiling and use this method to find miRNAs, which control organic development especially for nervous system. Materials and methods Eighteen organic samples included cerebrum and spinal cord samples from two aborted human fetuses. One was 12 gestational weeks old (G12w) and the other was 24 gestational weeks old (G24w). Global miRNA expression patterns of different organs were investigated using OMA and Northern blot. Conclusion The OMA revealed that 72–83% of miRNAs were expressed in human fetal organs. A series of microRNAs were found specifically and higher-expressed in the human fetal nervous system and confirmed consistently by Northern blot, which may play a critical role in nervous system development.

Human hepatocellular carcinoma (HCC) is one of the most common tumors worldwide, in which the genetic mechanisms of oncogenesis are still unclear. To investigate whether the genomic DNA copy number alterations may contribute to primary HCC, the cDNA microarray-based comparative genomic hybridization (CGH) analysis was here performed in 41 primary HCC infected by hepatitis B virus and 12 HCC cell lines. The resulting data showed that, on average, 7.25% of genome-wide DNA copy numbers was significantly altered in those samples (4.61±2.49% gained and 2.64±1.78% lost). Gains involving 1q, 6p, 8q and 9p were frequently observed in these cases; and whilst, losses involving Ip, 16q and 19p occurred in most patients. To address the correlation between the alteration of genomic DNA copy numbers and transcriptional expression, the same cDNA microarray was further applied in 20 HCC specimens and all available cell lines to figure out the gene expression profiles of those samples. Interestingly, the genomic DNA copy number alterations of most genes appeared not to be in generally parallel with the corresponding transcriptional expression. However, the transcriptional deregulation of a few genes, such as osteopontin (SPP1), transgelin 2 (TAGLN2) and PEG10, could be ascribed partially to their genomic aberrations, although the many alternative mechanisms could be involved in the deregulation of these genes. In general, this work would provide new insights into the genetic mechanisms in hepatocarcinogenesis associated with hepatitis B virus through the comprehensive survey on correlation between genomic DNA copy number alterations and transcriptional expression.

Pituitary, a master gland of neuroendocrine system, secretes hormones that orchestrate many physiological processes, under the regulation of multiple signaling pathways. To investigate the genes involved in hormones expression of human pituitary, homemade cDNA microarray containing 14,800 human genes/ESTs were used to profile the gene expression in both fetal and adult pituitaries. Seven hundred and twelve known genes changed over 2-fold between the both tissues. Of which, 23 genes were changed with hormones expression in aging were confirmed by RT-PCR, not only the known regulators such as Pit1, GATA4, ESRRA, GABA-A, and EMK, but also LOC55884, DUSP3, PNN, and RCL, which had not been reported to be involved in the hormones expression. Correspondingly, the mRNAs of GH, PRL, POMC, TSH-beta, FSH-beta, and LH-beta, was increased as much as 6- to 20-fold in adult pituitary than those in fetal pituitary, by real-time quantitative RT-PCR assay. In addition, the mRNAs of signaling pathways, such as cAMP-PKA-CREB, PI3K-Akt, and PKA-ERK were further investigated. Of them, it was only cAMP-PKA-CREB pathway, but not PI3K-Akt and PKA-ERK have the same expressing pattern as hormones. It suggested that cDNA microarray is highly advantages to profile the differential expressed genes that were involved in hormones expression of human pituitary, but it might ignore some responding proteins regulated posttranscriptionally.

Severe acute respiratory syndrome (SARS) is caused by the SARS coronavirus (SARS-CoV). There are many point mutations among SARS-CoV genome sequences. Previous studies suggested that the mutations are correlated closely with the SARS epidemic. It was found that the bases of six nucleotide positions (nt9404, nt9479, nt19838, nt21721, nt22222 and nt27827) with high-mutation rate have an important relationship with the SARS epidemic. For viral detection as well as genotyping, a universal microarray system was developed that combines RT-PCR and ligase detection reaction (LDR). The Zip Codes attached covalently to a slide remain constant and their complementary Zip Codes (cZip Codes) can be used for tagging target sequence, making the microarrays universal. The discriminating oligonucleotides contain on the 5′ end “cZip Codes” that are used to direct LDR product to specific Zip Codes attached covalently to a slide. Since Zip Codes have no homology to either the target sequence or to other sequences in the genomes of both human host and SARS-CoV, there was no false signal due to mismatch hybridizations. 20 samples assayed with the universal microarray were confirmed by DNA sequencing, demonstrating that this microarray system is a promising diagnostic tool for detection and genotyping of the SARS-CoV.

Peripheral tissue injury-induced central sensitization may result from the altered biochemical properties of spinal dorsal horn. However, peripheral nerve injury-induced modification of genes in the dorsal horn remains largely unknown. Here we identified strong changes of 14 channels, 25 receptors and 42 signal transduction related molecules in Sprague-Dawley rat dorsal spinal cord 14 days after peripheral axotomy by cDNA microarray. Twenty-nine genes were further confirmed by semiquantitative RT-PCR, Northern blotting, in situ hybridization and immunohistochemistry. These regulated genes included Ca2+ channel alpha1E and alpha2/delta1 subunits, alpha subunits for Na+ channel 1 and 6, Na+ channel beta subunit, AMAP receptor GIuR3 and 4, GABA(A) receptor alpha5 subunit, nicotinic acetylcholine receptor alpha5 and beta2 subunits, PKC alpha, betal and delta isozymes, JNK1-3, ERK2-3, p38 MAPK and BatK and Lyn tyrosine-protein kinases, indicating that several signal transduction pathways were activated in dorsal spinal cord by peripheral nerve injury. These results demonstrate that peripheral nerve injury causes phenotypic changes in spinal dorsal horn. Increases in Ca2+ channel alpha2/delta1 subunit, GABA(A) receptor alpha5 subunit, Na+ channels and nicotinic acetylcholine receptors in both dorsal spinal cord and dorsal root ganglia indicate their potential roles in neuropathic pain control.

In an attempt to characterize changes in transcription after a sub-chronic spinal cord injury (SCI), we investigated gene expression profiles using cDNA microarray. Among 7523 genes and expressed sequence tags (ESTs) examined, 444 transcripts, including 218 genes and 226 ESTs, were identified to be either up-regulated (373 of 444) or down-regulated (71 of 444) greater than 2.0-fold in the spinal cord at 14 days after a complete spinal transection at the 11th thoracic level in adult rats. Based on their potential function, these differentially expressed genes were categorized into seven classes which include cell division-related protein, channels and receptors, cytoskeletal elements, extracellular matrix proteins, metalloproteinases and inhibitors, growth-associated molecules, metabolism, intracellular transducers and transcription factors, as well as others. Strong expressional changes were found in all classes revealing the complexity and diversity of gene expression profiles following SCI. We verified array results with RT-PCR for eight genes, Northern blotting for nine genes, and in situ hybridization for one gene and immunohistochemistry for four genes. These analyses confirmed, to a large extent, that the array results have accurately reflected the molecular changes occurring at 14 days post-SCI. Importantly, the current study has identified a number of genes, including annexins, heparin-binding growth-associated protein (HB-GAM), P9ka (S100A4), matrix metalloproteinases, and lysozyme, that may shed new light on SCI-related inflammation, neuroprotection, neurite-outgrowth, synaptogenesis, and astrogliosis. In conclusion, the identification of molecular changes using the large-scale microarray analysis may lead to a better understanding of underlying mechanisms, thus, the development of new repair strategies for SCI.

Here we describe a novel mechanism for plasma membrane insertion of the delta opioid receptor (DOR). In small dorsal root ganglion neurons, only low levels of DORs are present on the cell surface, in contrast to high levels of intracellular DORs mainly associated with vesicles containing calcitonin gene-related peptide (CGRP). Activation of surface DORs caused Ca(2+) release from IP(3)-sensitive stores and Ca(2+) entry, resulting in a slow and long-lasting exocytosis, DOR insertion, and CGRP release. In contrast, membrane depolarization or activation of vanilloid and P2Y(1) receptors induced a rapid DOR insertion. Thus, DOR activation induces a Ca(2+)-dependent insertion of DORs that is coupled to a release of excitatory neuropeptides, suggesting that treatment of inflammatory pain should include blockade of DORs.

Aneuploidy with chromosome instability is a cancer hallmark. We studied chromosome 7 (Chr7) copy number variation (CNV) in gliomas and in primary cultures derived from them. We found tumor heterogeneity with cells having Chr7-CNV commonly occurs in gliomas, with a higher percentage of cells in high-grade gliomas carrying more than 2 copies of Chr7, as compared to low-grade gliomas. Interestingly, all Chr7-aneuploid cell types in the parental culture of established glioma cell lines reappeared in single-cell-derived subcultures. We then characterized the biology of three syngeneic glioma cultures dominated by different Chr7-aneuploid cell types. We found phenotypic divergence for cells following Chr7 mis-segregation, which benefited overall tumor growth in vitro and in vivo. Mathematical modeling suggested the involvement of chromosome instability and interactions among cell subpopulations in restoring the optimal equilibrium of tumor cell types. Both our experimental data and mathematical modeling demonstrated that the complexity of tumor heterogeneity could be enhanced by the existence of chromosomes with structural abnormality, in addition to their mis-segregations. Overall, our findings show, for the first time, the involvement of chromosome instability in maintaining tumor heterogeneity, which underlies the enhanced growth, persistence and treatment resistance of cancers. Published version

Emerging evidence suggests that the suppressive modulators released from nociceptive afferent neurons contribute to pain regulation. However, the suppressive modulators expressed in small-diameter neurons of the dorsal root ganglion remain to be further identified. The present study shows that the activin C expressed in small dorsal root ganglion neurons is required for suppressing inflammation-induced nociceptive responses. The expression of activin C in small dorsal root ganglion neurons of rats was markedly downregulated during the early days of peripheral inflammation induced by intraplantar injection of the complete Freund's adjuvant. Intrathecal treatment with the small interfering RNA targeting activin beta C or the antibodies against activin C could enhance the formalin-induced nociceptive responses, and impair the recovery from the complete Freund's adjuvant-induced thermal hyperalgesia. Intrathecally applied activin C could reduce nociceptive responses induced by formalin or complete Freund's adjuvant. Moreover, activin C was found to inhibit the inflammation-induced phosphorylation of extracellular signal-regulated kinase in the dorsal root ganglia and the dorsal spinal cord. Thus, activin C functions as an endogenous suppressor of inflammatory nociceptive transmission and may have a therapeutic potential for treatment of inflammatory pain.

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide and shows a propensity to metastasize and infiltrate adjacent and more distant tissues 1 . HCC is associated with multiple risk factors, including hepatitis B virus (HBV) infection, which is especially prevalent in China. Here, we used exome sequencing to identify somatic mutations in ten HBV-positive individuals with HCC with portal vein tumor thromboses (PVTTs), intrahepatic metastases. Both C:G>A: T and T:A>A:T transversions were frequently found among the 331 non-silent mutations. Notably, ARID1A, which encodes a component of the SWI/SNF chromatin remodeling complex, was mutated in 14 of 110 (13%) HBV-associated HCC specimens. We used RNA interference to assess the roles of 91 of the confirmed mutated genes in cellular survival. The results suggest that seven of these genes, including VCAM1 and CDK14, may confer growth and infiltration capacity to HCC cells. This study provides a view of the landscape of somatic mutations that may be implicated in advanced HCC. Hepatocellular carcinoma is associated with infection with HBV or hepatitis C virus (HCV), alcohol consumption and aflatoxin B1 (AFB1) contamination of food. Individuals with HCC with PVTTs, which are caused by tumor invasion and metastasis via the intra­ hepatic portal vein, have extremely poor prognoses 2,3 . To identify the genetic lesions in advanced HBV ­ associated HCC with intrahepatic metastasis, we employed two types of exome sequenc­ ing strategies, the Illumina/Solexa Genome Analyzer II and the ABI SOLiD platforms, to identify the somatic mutations in ten individuals with HCC with PVTTs (Supplementary Table 1). The average cov­ erage of each base in the target regions was 28 ­ fold and 88 ­ fold per tumor sample (primary tumor and matched PVTT) for the Illumina and ABI platforms, respectively (Online Methods, Supplementary Fig. 1 and Supplementary Table 2). Here, we propose 475 candidate

The motivation of this research is to establish a system of target genomic DNA capture and enrichment, which could be used in deep sequencing of target regions with next-generation sequencing. To design the 120 bp capture probes (baits) and prepare the SureSelect reagents, 2,414,977 bp human genomic sequence of 11,824 exons in 1250 genes were submitted to the Agilent eArray platform and manufactured by Agilent. Two human genomic DNA samples were used and conducted the successive experiments for sequencing library construction: shearing fragmentation by sonication, blunt-ending and phosphorylation, adaptor ligation, 150-200 bp fragments size selection, followed by hybridization with the baits, hybrid selection with magnetic beads, and PCR amplification. Prior to SOLiD sequencing reaction, the libraries were amplified with emulsion PCR and enriched with the P2 enrichment beads. The library samples were loaded to sequencing Chip for Work Flow Analysis (WFA) or sequencing running with default parameters. The results displayed that 46 509 baits were designed and synthesized for 11,147 gene regions, and SureSelect capture probe regent was prepared. Real-time PCR showed the target enrichment efficiency up to 2(9) times with the SureSelect system. WFA revealed that the libraries were suitable for SOLiD Sequencing. The sequencing data revealed that 70% of the unique mapped sequence tags matched the target regions, and the average coverage of the target regions were above 200-fold. All these demonstrated the feasibility of the established system of target genome sequence capture for next generation DNA sequencing.

Reduction of follistatin-like 1 in primary afferent neurons contributes to neuropathic pain hypersensitivity

B-type natriuretic peptide (BNP) has been known to be secreted from cardiac myocytes and activate its receptor, natriuretic peptide receptor-A (NPR-A), to reduce ventricular fibrosis. However, the function of BNP/NPR-A pathway in the somatic sensory system has been unknown. In the present study, we report a novel function of BNP in pain modulation. Using microarray and immunoblot analyses, we found that BNP and NPR-A were expressed in the dorsal root ganglion (DRG) of rats and upregulated after intraplantar injection of complete Freund's adjuvant (CFA). Immunohistochemistry showed that BNP was expressed in calcitonin gene-related peptide (CGRP)-containing small neurons and IB4 (isolectin B4)-positive neurons, whereas NPR-A was present in CGRP-containing neurons. Application of BNP reduced the firing frequency of small DRG neurons in the presence of glutamate through opening large-conductance Ca2+-activated K+channels (BKCachannels). Furthermore, intrathecal injection of BNP yielded inhibitory effects on formalin-induced flinching behavior and CFA-induced thermal hyperalgesia in rats. Blockade of BNP signaling by BNP antibodies or cGMP-dependent protein kinase (PKG) inhibitor KT5823 [(9S,10R,12R)-2,3,9,10,11,12-hexahydro-10-methoxy-2,9-dimethyl-1-oxo-9,12-epoxy-1H-diindolo[1,2,3-fg:3′,2′,1′-kl]pyrrolo[3,4-i][1,6]benzodiazocine-10-carboxylic acid methyl ester] impaired the recovery from CFA-induced thermal hyperalgesia. Thus, BNP negatively regulates nociceptive transmission through presynaptic receptor NPR-A, and activation of the BNP/NPR-A/PKG/BKCachannel pathway in nociceptive afferent neurons could be a potential strategy for inflammatory pain therapy.

Large efforts have been taken to search for genes responsible for type 2 diabetes (T2D), but have resulted in only about 20 in humans due to its complexity and heterogeneity. The GK rat, a spontanous T2D model, offers us a superior opportunity to search for more diabetic genes. Utilizing array comparative genome hybridization (aCGH) technology, we identifed 137 non-redundant copy number variation (CNV) regions from the GK rats when using normal Wistar rats as control. These CNV regions (CNVRs) covered approximately 36 Mb nucleotides, accounting for about 1% of the whole genome. By integrating information from gene annotations and disease knowledge, we investigated the CNVRs comprehensively for mining new T2D genes. As a result, we prioritized 16 putative protein-coding genes and two microRNA genes (rno-mir-30b and rno-mir-30d) as good candidates. The catalogue of CNVRs between GK and Wistar rats identified in this work served as a repository for mining genes that might play roles in the pathogenesis of T2D. Moreover, our efforts in utilizing bioinformatics methods to prioritize good candidate genes provided a more specific set of putative candidates. These findings would contribute to the research into the genetic basis of T2D, and thus shed light on its pathogenesis.

Coordination of cell differentiation and proliferation is a key issue in the development process of multi-cellular organisms and stem cells. Here we provide evidence that the establishment of adipocyte differentiation of 3T3-L1 cells requires two processes: the licensing of an adipogenesis gene-expression program within a particular growth-arrest stage, i.e., the contact-inhibition stage, and then the execution of this program in a cell-cycle-independent manner, by which the licensed progenitors are differentiated into adipocytes in the presence of inducing factors. Our results showed that differentiation licensing of 3T3-L1 cells during the contact-inhibition stage involved epigenetic modifications such as DNA methylation and histone modifications, whereas disturbing these epigenetic modifications by DNA methylation inhibitors or RNAi during the contact-inhibition stage significantly reduced adipogenesis efficiency. More importantly, when these licensed 3T3-L1 cells were re-cultured under non-differentiating conditions or treated only with insulin, this adipogenesis commitment could be maintained from one cell generation to the next, whereby the licensed program could be activated in a cell-cycle-independent manner once these cells were subjected to adipogenesis-inducing conditions. This result suggests that differentiation licensing and differentiation execution can be uncoupled and disparately linked to cell proliferation. Our findings deliver a new concept that cell-fate decision can be subdivided into at least two stages, licensing and execution, which might have different regulatory relationships with cell proliferation. In addition, this new concept may provide a clue for developing new strategies against obesity.

Background The pituitary is a critical neuroendocrine gland that is comprised of five hormone-secreting cell types, which develops in tandem during the embryonic stage. Some essential genes have been identified in the early stage of adenohypophysial development, such as PITX1, FGF8, BMP4 and SF-1. However, it is likely that a large number of signaling molecules and transcription factors essential for determination and terminal differentiation of specific cell types remain unidentified. High-throughput methods such as microarray analysis may facilitate the measurement of gene transcriptional levels, while Expressed sequence tag (EST) sequencing, an efficient method for gene discovery and expression level analysis, may no-redundantly help to understand gene expression patterns during development. Results A total of 9,271 ESTs were generated from both fetal and adult pituitaries, and assigned into 961 gene/EST clusters in fetal and 2,747 in adult pituitary by homology analysis. The transcription maps derived from these data indicated that developmentally relevant genes, such as Sox4, ST13 and ZNF185, were dominant in the cDNA library of fetal pituitary, while hormones and hormone-associated genes, such as GH1, GH2, POMC, LHβ, CHGA and CHGB, were dominant in adult pituitary. Furthermore, by using RT-PCR and in situ hybridization, Sox4 was found to be one of the main transcription factors expressed in fetal pituitary for the first time. It was expressed at least at E12.5, but decreased after E17.5. In addition, 40 novel ESTs were identified specifically in this tissue. Conclusion The significant changes in gene expression in both tissues suggest a distinct and dynamic switch between embryonic and adult pituitaries. All these data along with Sox4 should be confirmed to further understand the community of multiple signaling pathways that act as a cooperative network that regulates maturation of the pituitary. It was also suggested that EST sequencing is an efficient means of gene discovery.

To reduce the huge labor-cost in the screening in traditional monoclonal antibody generation, We established a new system for monoclonal antibody generation integrating with protein array. BALB/c mice were immunized by eight recombinant proteins respectively, and the positive hybridoma cells were obtained by cell fusion and ELISA screening. All the eight kinds of positive hybridoma cells were mixed, cloned, screened by protein array, and definite dilution cloned.175 single cell clones were obtained by complex cloning, and 119 of those were positive clones. Then 8 positive cell lines were generated by the following 2 rounds definite dilution cloning. By comparing with the traditional method, we got 8 monoclonal antibodies using the combined protein array screening and multiplex cloning method in 1 cycle, and fewer amounts of antigens were used. As a result, the combined protein array and multiplex cloning method could be used as an economical, rapid and simple tool applying in high throughput monoclonal antibody generation.

To investigate the association of thiazide-sensitive Na+ -Cl* cotransporter (TSC) gene 1784C/T and 2736G/A polymorphisms with the risk of essential hypertension (EH) in a Han nationality population.A community-based, case-control study including 190 EH patients and 94 sex- and age-matched controls was conducted. Genotypes of TSC gene 1784C/T and 2736G/A polymorphisms were analyzed by gene chip technology.The genotype (1784C/T CC, CT, TT:87, 88, 15 vs 36, 52, 6û2736G/A GG, AG, AA:167, 22, 1 vs 83, 10, 1) and alleles frequency (1784C/T C, T:68.9%, 31.1% vs 66.0%, 34.0%; 2736G/A G,A:93.7%, 6.3% vs 93.6%, 6.4%) distribution of 1784C/T and 2736G/A showed no significant difference between the EH group and the control group (P0.05). Moreover, no significant difference was observed in the frequencies distribution of four haplotypes (P0.05); Logistic regression analysis of haplotypes showed that the risk of EH had no significant difference in the population with different haplotypes (P0.05).The 1784C/T and 2736G/A polymorphisms of TSC gene may not play an important role in the etiology of EH in a Han nationality population. The studies in the future are warranted to validate our findings.

MicroRNAs (miRNAs) are a group of RNAs that play important roles in regulating gene expression and protein translation. In a previous study, we established an oligonucleotide microarray platform to detect miRNA expression. Because it contained only hundreds of probes, data normalization was difficult. In this study, the microarray data for eight miRNAs extracted from inflamed rat dorsal root ganglion (DRG) tissue were normalized using 15 methods and compared with the results of real-time polymerase chain reaction. It was found that the miRNA microarray data normalized by the print-tip loess method were the most consistent with results from real-time polymerase chain reaction. Moreover, the same pattern was also observed in 14 different types of rat tissue. This study compares a variety of normalization methods and will be helpful in the preprocessing of miRNA microarray data.

Background The renin-angiotensin-aldosterone system (RAAS) is important for the development of essential hypertension, and many antihypertensive drugs target it. This study was undertaken to determine whether polymorphisms in the renin-angiotensin-aldosterone system are related to the blood pressure (BP) response to diuretic treatment in a Chinese Han ethnic population. Methods Fifty-four patients with essential hypertension received hydrochlorothiazide (12.5 mg, once daily) as monotherapy for four weeks. Seven polymorphisms in RAAS genes were genotyped by gene chip technology. The relationship between these polymorphisms and the change in blood pressure was observed after the 4-week treatment. Results The patients with angiotensinogen (AGT) -6G allele showed a greater reduction in diastolic BP (P= 0.025) and mean BP (P=0.039) than those carrying AA genotype. Patients carrying aldosterone synthase (CYP11B2) CC genotype exhibited a greater BP reduction than those carrying CT and TT genotypes (systolic BP: P= 0.030; diastolic BP: P= 0.026; mean BP: P=0.003). In addition, patients with a combination of CYP11B2 CC genotype and angiotensin converting enzyme (ACE) D allele might have a more pronounced reduction of systolic BP than those with any other genotypic combinations of the two genes (P= 0.007). Conclusions AGT-6G allele, CYP11B2 -344CC genotype and its combination with ACE D allele are associated with BP response to hydrochlorothiazide treatment. Larger studies are warranted to validate this finding. Chin Med J 2007;120(9):782-786 ssential hypertension (EH) is a polygenetic disease that occurs as a consequence of complex interactions of multiple genetic polymorphisms and environmental factors. High blood pressure (BP) can increase the risk of cardiovascular and cerebrovascular diseases. The renin-angiotensin-aldosterone system (RAAS) plays a key role in regulating BP by maintaining vascular tone and the balance of water and sodium. Many antihypertensive drugs target the RAAS, but the effect is quite different in individual hypertensive patients. The relationships between the polymorphisms of RAAS genes and EH have been extensively studied. Most studies have shown that angiotensinogen (AGT), angiotensin II type 1 receptor (AT1R), angiotensin converting enzyme (ACE), and aldosterone synthase (CYP11B2) gene polymorphisms are associated with the levels of BP and the risk of EH. 1-7

Ninety-eight genes/ESTs with differential expressions in epididymal adipose tissue of fed and 3-day fasting (F3) rats were identified by microarray analysis. Genes for lipogenesis, glycolysis, and glucose aerobic oxidation were decreased in response to starvation. Further study was performed to investigate the expression patterns of these genes in rat tissues after short- and long-term starvations. The results of the increased expression of the pyruvate dehydrogenase kinase 4 (PDK4) gene and decreased pyruvate dehydrogenase (PDH) in rat muscle together with decreased fatty acid synthase (FAS) in rat adipose tissue after 1 day of fasting (F1) suggested from transcriptional level that glucose aerobic oxidation was down-regulated in rat muscle and synthesis of saturated fatty acids was inhibited in rat adipose tissue after short-term fasting. It was noted that the transcriptions of genes involved in the fatty acid oxidation, such as very-long-chain Acyl-CoA dehydrogenase (LCAH), Acyl-CoA oxidase (ACO), carnitine palmitoyltransferase-I (CPT-I), and carnitine-acylcarnitine translocase (CAT)L, were greatly increased in F1 rat liver, then began to decrease in F3 and 5-day fasting (F5) rat liver, combined with significantly increased serum non-esterified fatty acids (NEFA) in F1 rats and increased urea in F5 rats, suggesting that inhibition of the oxidation of lipid and not the decreased availability of these fuels may play an important role in the phase II-phase III of fasting transition in the long-term fasting rats.

Synaptoporin and synaptophysin are integral membrane components of synaptic vesicles. The distribution of synaptoporin and its relationship with synaptophysin in sensory afferent fibers remain unclear. In the present study, we showed that in the rat dorsal root ganglia synaptoporin was expressed in subsets of small neurons that contain either calcitonin gene-related peptide or isolectin B4, and was distributed in their afferent terminals in laminae I-II of the spinal cord. Synaptophysin was expressed in 57% of synaptoporin-containing small dorsal root ganglion neurons and in large dorsal root ganglion neurons. In the spinal dorsal horn, synaptophysin-immunolabeling was weak in the afferent fibers in lamina I, outer lamina II and the dorsal part of inner lamina II, but strong in the afferent fibers in laminae III-IV. However, a subpopulation of isolectin B4-positive small dorsal root ganglion neurons expressed both synaptoporin and synaptophysin, and their afferent fibers were mainly distributed in the ventral part of inner lamina II. After peripheral nerve injury, synaptoporin expression was up-regulated in small dorsal root ganglion neurons, and synaptoporin level was increased in their afferent terminals. Thus, synaptoporin and synaptophysin have topographically distinct distributions in afferent fibers. Synaptoporin is a major synaptic vesicle protein in A delta- and C-fibers in both physiological and neuropathic pain states. (c) 2006 IBRO. Published by Elsevier Ltd. All rights reserved.

The molecular modification of the pain pathway represents one of the major mechanisms underlying neuropathic pain. Recently, gene array studies have been carried out to identify the genes that are regulated at the spinal cord level after peripheral nerve injury. These studies demonstrate that peripheral nerve injury causes marked changes in gene expression in both the dorsal root ganglion (DRG) and the dorsal spinal cord. The markedly regulated molecules include, for example, neuropeptides, receptors, ion channels, signal transduction molecules and synaptic vesicle proteins. Upregulation of the Ca2+ channel alpha2/delta1 subunit, gamma-aminobutyric acid A receptor alpha5 subunit, Na+ channels and nicotinic acetylcholine receptors in the DRG and dorsal spinal cord indicates their potential roles in neuropathic pain control.

Peripheral tissue injury-induced central sensitization may result from the altered biochemical properties of spinal dorsal horn. However, peripheral nerve injury-induced modification of genes in the dorsal horn remains largely unknown. Here we identified strong changes of 14 channels, 25 receptors and 42 signal transduction related molecules in Sprague-Dawley rat dorsal spinal cord 14 days after peripheral axotomy by cDNA microarray. Twenty-nine genes were further confirmed by semiquantitative RT-PCR, Northern blotting, in situ hybridization and immunohistochemistry. These regulated genes included Ca2+ channel alpha1E and alpha2/delta1 subunits, alpha subunits for Na+ channel 1 and 6, Na+ channel beta subunit, AMAP receptor GluR3 and 4, GABAA receptor alpha5 subunit, nicotinic acetylcholine receptor alpha5 and beta2 subunits, PKC alpha, betaI and delta isozymes, JNK1-3, ERK2-3, p38 MAPK and BatK and Lyn tyrosine-protein kinases, indicating that several signal transduction pathways were activated in dorsal spinal cord by peripheral nerve injury. These results demonstrate that peripheral nerve injury causes phenotypic changes in spinal dorsal horn. Increases in Ca2+ channel alpha2/delta1 subunit, GABAA receptor alpha5 subunit, Na+ channels and nicotinic acetylcholine receptors in both dorsal spinal cord and dorsal root ganglia indicate their potential roles in neuropathic pain control.

We currently identified a liver-specific gene that encodes a novel zona pellucida (ZP) domain-containing protein named liver-specific ZP domain-containing protein (LZP). The full-length complementary DNA (cDNA) of human LZP has 2,255 bp with a complete open reading frame (ORF) of 1,635 bp. The gene is localized on chromosome 10q21.3 and spans 40 kb with 9 encoding exons and 8 introns. The deduced protein sequence has 545 amino acid residues, with an N-terminal signal peptide followed by 3 epidermal growth factor (EGF)-like domains and a ZP domain in C-terminal section. Interestingly, human LZP is expressed specifically in liver out of 23 tissues examined, and its mouse counterpart was detected at very early stage during embryo development. Moreover, LZP can be secreted into blood, albeit the protein was localized mainly on the nuclear envelop of hepatocytes. Most importantly, LZP is down-regulated in hepatocellular carcinoma (HCC) and HCC cell lines; meanwhile, the decreased level of hLZP messenger RNA (mRNA) could, at least in some HCC samples, be related to the methylation status of the putative LZP promoter. However, overexpression of hLZP in HCC cell line SMMC-7721 and human liver cell line L02 by stable cell transfection did not inhibit cell growth, implying that the down-regulation of hLZP in HCC might be a consequence of the dedifferentiation involved in hepatocarcinogenesis. In conclusion, these data suggest that LZP is a liver-specific protein involved possibly in hepatocellular function and development, and the protein could be used as potential negative biomarker for HCC pathologic diagnosis.

To clone gene fragments from suppression substructive library established for screening down-regulated genes in gastric carcinoma, and obtain the full-length novel gene.Gene fragments were identified by sequencing plasmids of positive colonies chosen randomly. One gene fragment was amplified by RACE, and the full-length novel gene was obtained. Expression of novel gene mRNA was respectively detected by semi-quantitative PCR in the gastric carcinoma tissues and counterpart normal gastric mucous membrane of 25 patients with gastric cancer. The structure of the full-length novel gene, location on chromosome, property of protein encoded by full-length novel gene and its function were investigated by Bio-message technique.One 331 bp gene fragment was cloned, and its full-length novel gene obtained by RACE. The novel full-length gene was named GDDR, registered in the number of AF494509 by GenBank. Significant down-regulated expression of GDDR gene mRNA in gastric carcinoma tissues was confirmed (GDDR/beta-actin 13.474 +/- 5.059 vs 1.041 +/- 0.202, P0.01). GDDR was located in chromosome 2p13 with 5 exons. As one member of new BRICHO family as CA11, GDDR encoding protein with transmembrane peptide revealed homology to protein encoded by CA11.A novel full-length gene GDDR is obtained. GDDR likely is another gene of BRICHO family related to gastric cancer.

Using cDNA array, we observed the expression of eight members of the fibroblast growth factor (FGF) family, FGF 2, 5, 7,9,10,13 and 14, in rat lumbar 4 and 5 dorsal root ganglia (DRGs). Over a period of 28 days after sciatic nerve transection, the array signals for FGF 2 and 7 were significantly increased in the DRGs, while FGF 13 decreased. Using the reverse transcription polymerase chain reaction (RT-PCR), we confirmed the axotomy-induced changes in the expression of FGF 7 and 13. In situ hybridization showed that FGF 13 was expressed in 60% of DRG neurons under normal circumstance. Seven days after axotomy the number of FGF 13-positive neurons was decreased to 18%, but partially recovered to 40% after 28 days. FGF 13 immunoreactivity was also decreased. These data indicate that FGFs are important for DRG neurons under normal circumstance and after nerve injury.

Phenotypic modification of dorsal root ganglion (DRG) neurons represents an important mechanism underlying neuropathic pain. However, the nerve injury-induced molecular changes are not fully identified. To determine the molecular alterations in a broader way, we have carried out cDNA array on the genes mainly made from the cDNA libraries of lumbar DRGs of normal rats and of rats 14 days after peripheral axotomy. Of the 7,523 examined genes and expressed sequence tags (ESTs), the expression of 122 genes and 51 expressed sequence tags is strongly changed. These genes encompass a large number of members of distinct families, including neuropeptides, receptors, ion channels, signal transduction molecules, synaptic vesicle proteins, and others. Of particular interest is the up-regulation of γ-aminobutyric acid A receptor α5 subunit, peripheral benzodiazepine receptor, nicotinic acetylcholine receptor α7 subunit, P2Y1 purinoceptor, Na + channel β2 subunit, and L-type Ca 2+ channel α2δ-1 subunit. Our findings therefore reveal dynamic and complex changes in molecular diversity among DRG neurons after axotomy.

Summary Setd2 is known as a histone-H3K36-specific methyltransferase. However, its role in physiological function remains unclear. In this study, we show that Setd2 mainly regulates differentiation of murine embryonic stem cells (mESCs) toward primitive endoderm. Furthermore, we show that downregulated endoderm-related genes in Setd2 −/− mESCs are associated with an aberrantly low level of Erk activity and that enforced expression of Fgfr3 can rescue the defective Erk pathway in Setd2 −/− mESCs. Interestingly, the transcriptional initiation of Fgfr3 is directly regulated through histone H3K36me3 modification in its distal promoter region by Setd2. These results indicate that Setd2 controls the primitive endoderm differentiation of mESCs by regulating the Fgfr3-Erk signaling.

Gastric cancer is the fourth most common cancer in the world and the second leading cause of cancer-related death. More than 80% of diagnoses occur at the middle to late stage of the disease, highlighting an urgent need for novel biomarkers detectable at earlier stages. Recently, aberrantly expressed microRNAs (miRNAs) have received a great deal of attention as potential sensitive and accurate biomarkers for cancer diagnosis and prognosis. This review summarizes the current knowledge about potential miRNA biomarkers for gastric cancer that have been reported in the publicly available literature between 2008 and 2013. Available evidence indicates that aberrantly expressed miRNAs in gastric cancer correlate with tumorigenesis, tumor proliferation, distant metastasis and invasion. Furthermore, tissue and cancer types can be classified using miRNA expression profiles and next-generation sequencing. As miRNAs in plasma/serum are well protected from RNases, they remain stable under harsh conditions. Thus, potential functions of these circulating miRNAs can be deduced and may implicate their diagnostic value in cancer detection. Circulating miRNAs, as well as tissue miRNAs, may allow for the detection of gastric cancer at an early stage, prediction of prognosis, and monitoring of recurrence and/or lymph node metastasis. Taken together, the data suggest that the participation of miRNAs in biomarker development will enhance the sensitivity and specificity of diagnostic and prognostic tests for gastric cancer.

Human hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. In this work, we report on a comprehensive characterization of gene expression profiles of hepatitis B virus-positive HCC through the generation of a large set of 5′-read expressed sequence tag (EST) clusters (11,065 in total) from HCC and noncancerous liver samples, which then were applied to a cDNA microarray system containing 12,393 genes/ESTs and to comparison with a public database. The commercial cDNA microarray, which contains 1,176 known genes related to oncogenesis, was used also for profiling gene expression. Integrated data from the above approaches identified 2,253 genes/ESTs as candidates with differential expression. A number of genes related to oncogenesis and hepatic function/differentiation were selected for further semiquantitative reverse transcriptase–PCR analysis in 29 paired HCC/noncancerous liver samples. Many genes involved in cell cycle regulation such as cyclins, cyclin-dependent kinases, and cell cycle negative regulators were deregulated in most patients with HCC. Aberrant expression of the Wnt-β-catenin pathway and enzymes for DNA replication also could contribute to the pathogenesis of HCC. The alteration of transcription levels was noted in a large number of genes implicated in metabolism, whereas a profile change of others might represent a status of dedifferentiation of the malignant hepatocytes, both considered as potential markers of diagnostic value. Notably, the altered transcriptome profiles in HCC could be correlated to a number of chromosome regions with amplification or loss of heterozygosity, providing one of the underlying causes of the transcription anomaly of HCC.

The Y2 subtype of neuropeptide tyrosine (NPY) receptors (Y2R) and some neuropeptides have been studied with in situ hybridization in sensory and autonomic neurons of rat and monkey. Between 10% and 20% of the lumbar dorsal root ganglion (DRG) neuron profiles (NPs) contain Y2R mRNA in the rat and monkey. In rat DRGs Y2R mRNA is expressed in calcitonin gene-related peptide (CGRP)-positive, medium-sized, and large neurons, that is in a complementary fashion to the Y1R that is located in small CGRP neurons. In monkey DRGs Y2R mRNA is expressed mainly in small neurons. Peripheral axotomy up-regulates the Y2R in small and large DRG neurons in both species. Y2R and NPY mRNAs are colocalized in many large neurons in axotomized rat DRGs. Y2R mRNA is expressed in 50% of the NPs in the nodose ganglion with a modest increase after axotomy. Y2R mRNA is detected in a few NPs in normal rat superior cervical ganglia, with a marked increase after transection of the carotid nerves. No Y2R mRNA-positive, but many (≈30%) weakly Y1R mRNA-positive NPs were found in the sphenopalatine ganglion. Finally, Y2R mRNA levels increase in rat spinal motoneurons after axotomy. Thus, under normal circumstances NPY may act on Y1 and Y2Rs expressed, respectively, in small and large CGRP-positive DRG neurons in the rat. Y2R may be an important receptor in the viscero-sensory neurons. Y2Rs may be particularly important after axotomy serving as presynaptic and/or autoreceptors on rat DRG, superior cervical ganglion, and nodose ganglion neurons and as presynaptic receptors in monkey DRG neurons.

Background MicroRNAs (miRNAs) are a large group of RNAs that play important roles in regulating gene expression and protein translation. Several studies have indicated that some miRNAs are specifically expressed in human, mouse and zebrafish tissues. For example, miR-1 and miR-133 are specifically expressed in muscles. Tissue-specific miRNAs may have particular functions. Although previous studies have reported the presence of human, mouse and zebrafish tissue-specific miRNAs, there have been no detailed reports of rat tissue-specific miRNAs. In this study, Home-made rat miRNA microarrays which established in our previous study were used to investigate rat neural tissue-specific miRNAs, and mapped their target genes in rat tissues. This study will provide information for the functional analysis of these miRNAs. Results In order to obtain as complete a picture of specific miRNA expression in rat neural tissues as possible, customized miRNA microarrays with 152 selected miRNAs from miRBase were used to detect miRNA expression in 14 rat tissues. After a general clustering analysis, 14 rat tissues could be clearly classified into neural and non-neural tissues based on the obtained expression profiles with p values < 0.05. The results indicated that the miRNA profiles were different in neural and non-neural tissues. In total, we found 30 miRNAs that were specifically expressed in neural tissues. For example, miR-199a was specifically expressed in neural tissues. Of these, the expression patterns of four miRNAs were comparable with those of Landgraf et al., Bak et al., and Kapsimani et al. Thirty neural tissue-specific miRNAs were chosen to predict target genes. A total of 1,475 target mRNA were predicted based on the intersection of three public databases, and target mRNA's pathway, function, and regulatory network analysis were performed. We focused on target enrichments of the dorsal root ganglion (DRG) and olfactory bulb. There were four Gene Ontology (GO) functions and five KEGG pathways significantly enriched in DRG. Only one GO function was significantly enriched in the olfactory bulb. These targets are all predictions and have not been experimentally validated. Conclusion Our work provides a global view of rat neural tissue-specific miRNA profiles and a target map of miRNAs, which is expected to contribute to future investigations of miRNA regulatory mechanisms in neural systems.