Genome-wide screen for serum microRNA expression profile in mfat-1 transgenic mice

n-3 Polyunsaturated fatty acids (n-3 PUFAs) contribute to preventing many types of diseases, including cancer; however, a high n-6 polyunsaturated fatty acids (n-6 PUFAs) intake in modern diets has the opposite effect. Previously, we developed a transgenic mouse model that expresses a gene, fat-1, encoding an n-3 fatty acid desaturase, which converts n-6 PUFAs to n-3 PUFAs in vivo. MicroRNAs (miRNAs) in serum are stable, reproducible, and consistent among individuals of the same species and serve as potential biomarkers for the detection of cancers and other diseases. Employing illumina sequencing, we analyzed all the serum miRNAs in wild-type and mfat-1 transgenic mice. Using quantitative real-time PCR (RT-qPCR), we identified 12 miRNAs that were highly expressed in mfat-1 mice. Pathway analysis of targets regulated by these miRNAs revealed a significant number of genes involved in the development of cancer, including phosphatidylinositol 3-kinase (PI3K), mitogen-activated protein kinases (MAPK), and mammalian target of rapamycin (mTOR), which suggested a relationship between n-3 PUFAs and cancer prevention.     

Gene expression profile of normal lungs predicts genetic predisposition to lung cancer in mice

Genetic susceptibility to lung tumorigenesis shows large variations among mouse strains. To test whether genetic predisposition to lung tumorigenesis is associated with a specific gene expression profile in normal lungs, we analyzed gene expression in 16 inbred strains of known susceptibility/resistance to lung tumorigenesis, using the RIKEN mouse full-length cDNA 19K microarray set. The strain-specific expression profile of 91 cDNA clones correlated with strain lung tumor susceptibility/resistance and predicted, by principal component analysis, the genetic predisposition to lung tumorigenesis in mice.     

Gene expression array profile of human osteosarcoma

The aims of this pilot study were to determine whether needle and open biopsies from osteosarcoma (OS) provide sufficient quality of mRNA for cDNA array analyses to gain insights into the expression profile of OS. A total of 22 samples collected from OS were used for array analyses. A primary cell culture was also established from one of the OS biopsies. Total RNA was extracted and probes were generated for cDNA arrays. cDNA probes were made for all the 22 samples. Two of these samples were needle core bone biopsies. Statistical analysis confirmed the reliability of array data obtained in 16 of the 22 samples. Known genes involved in bone metabolism and osteosarcoma were identified as highly expressed, and the putative new marker Ezrin was also identified. Confirmatory immunohistochemical staining using the Ezrin antibody was performed in a selection of samples.     

Gene expression profile of AIDS-related Kaposi's sarcoma

Background  

Kaposi's Sarcoma (KS) is a proliferation of aberrant vascular structures lined by spindle cells, and is caused by a gammaherpes virus (HHV8/KSHV). Its course is aggravated by co-infection with HIV-1, where the timing of infection with HIV-1 and HHV8 is important for the clinical outcome.     

DNA binding protein A expression and methylation status in hepatocellular carcinoma and the adjacent tissue

We investigated the expression and promoter methylation of dbpA in human hepatocellular carcinoma (HCC) and examined their correlation with clinicopathological features. In 96 paired samples of HCC and adjacent non-tumorous liver, and 10 normal liver specimens, dbpA mRNA was quantified by real-time RT-PCR, and promoter methylation was examined by methylation-specific polymerase chain reaction and bisulfite sequencing. The results showed that dbpA mRNA expression levels were higher in HCC compared to corresponding non-tumor tissues (P<0.01) and higher in non-virus-associated HCC compared to virus-associated cases (P<0.01). dbpA promoter was methylated in 37.7% of HCC samples and the promoter methylation was significantly correlated with the low expression of dbpA in non-virus-associated HCC (P<0.01), but not in virus-associated HCC. Surprisingly, poor prognosis was more significantly associated with high dbpA expression in non-tumorous liver (P=0.018) but not with that in HCC. Non-tumorous tissues consist of chronic hepatitis or liver cirrhosis, and these conditions are the background of hepatocarcinogenesis, defined as the hypercarcinogenic state. Our results suggest that the high expression of dbpA in the hypercarcinogenic state is an indicator of poor prognosis.     

Gene expression profiles of diabetic mice treated with whole body hyperthermia: A high-density DNA microarray analysis

Previously we have demonstrated that whole body hyperthermia (WBH) improves insulin resistance in diabetic mice. The aim of the present study was to perform a gene expression analysis of the liver and adipose tissue of obesity-induced insulin resistant diabetic mice (db/db mice) after WBH and to define the molecules that play the important role in improvement of insulin resistance by WBH. Male db/db mice were treated with WBH 3 times per week for 12 weeks. Total RNA was extracted from the liver and adipose tissue of db/db mice, and differences in the gene expression profiles among db/+ mice, untreated db/db mice, and WBH-treated db/db mice were investigated using a high-density DNA microarray. WBH directly targets liver and adipose tissue, resulting in modifications in NF-κB and IL-6 signalling pathways, as well as lipid metabolism. Although the mechanisms have not yet been completely investigated, we can conclude that WBH may provide a new therapeutic or preventive modality against type 2 diabetes mellitus and metabolic or insulin resistance syndrome through the modification of several signalling pathways.     

c-fos expression induces bone tumors in transgenic mice

The proto-oncogene c-fos has been isolated as the cellular homolog of the v-fos gene found in the osteosarcoma inducing FBR- and FBJ-murine sarcoma viruses (MSV). Expression of the c-fos gene in transgenic mice leads to the development of bone lesions of which about half progress to bone tumors mainly chondrosarcomas. The tumors display a strong preference for males and have a latency with a mean of 9.5 months. However, also mice without visible lesions develop bone tumors with the same sex preference and latency. These consequences of c-fos expression are independent of the chosen promoter but dependent on a replacement of 3' noncoding sequences of c-fos by a long terminal repeat (LTR) of the FBJ-MSV virus.     

Down-regulation of c-MYC antigen expression in lymphocytes of Emu-c-myc transgenic mice treated with anti-c-myc DNA methylphosphonates.

In transgenic mice bearing a murine immunoglobulin enhancer/c-myc fusion transgene (Emu-myc), it was found that antisense DNA methylphosphonates targeted against c-myc mRNA inhibited production of c-MYC protein in peripheral lymphocytes. The decrease in protein was measured 3-4 h after i.v. administration of a 300-nmol dose. c-MYC was detected by immunofluorescence of fixed cells stained with an anti-c-MYC antiserum. In addition, DNA methylphosphonates did not induce acute toxicity following i.v. administration of a 300-nmol dose. An identically administered scrambled sequence oligomer did not decrease c-MYC protein or induce toxicity. Finally, recovery of DNA methylphosphonates from the blood plasma of treated mice indicated that the oligomers remained intact up to 3 h, while their concentrations decreased rapidly for the first h, then slowly decreased over the next 2 h. This is the first demonstration of sequence-specific antisense DNA methylphosphonate inhibition of gene expression in the bloodstream of an animal model.     

CC族趋化因子结合蛋白D6在乳腺癌中的表达及其调节

目的：研究CC族趋化因子结合蛋白D6在乳腺癌中的组成性表达及细胞因子IL-1β诱导后D6表达的改变。方法：采用半定量RT-PCR法检测D6mRNA在人乳腺癌细胞株、乳腺癌组织以及正常脾组织中的表达，并用实时荧光定量-PCR进一步验证其在细胞中表达的差异；Western blot法分析D6蛋白在乳腺癌细胞中的表达；用重组人IL-1β（0．5ng／mL，1ng／mL，2ng／mL）刺激MDA-MB-231细胞24h，实时荧光定量-PCR分析肺基因表达的改变。结果：D6mRNA在所有9种人乳腺癌细胞系、4例乳腺癌组织以及作为阳性对照的人正常脾组织中均可检出，其表达水平因细胞的不同而异，其中MCF-7、ZR-75-1和SK-BR-3细胞的表达量较高。MDA-MB-435和MDA-MB-231细胞中可检测出D6蛋白。此外，以MDA-MB-231细胞为对象的细胞因子诱导实验结果显示，IL-1β可呈剂量依赖性地促进嘶的基因表达。结论：D6分子在来源于不同患者的乳腺癌组织及生物学特性各异的多种人乳腺癌细胞系中均呈组成性表达，提示CC族趋化因子的结合蛋D6可能参与乳腺癌中趋化因子的调控，从而影响乳腺癌的发生、发展过程。     

Gene expression profile analysis by DNA microarrays: a new approach to assess functional genomics in diseases

A biologically based and potentially powerful way to characterize human diseases has arisen from the new science of genomics. One of the methodologies to provide a systematic way to observe and characterize gene expression programs is the DNA microarrays (also called gene chips). This modern genomic analysis tool shows the promise of providing an unbiased approach to detecting biologically relevant differences within clinically similar diseases. Taking advantage of the initial reports that appeared in the literature on this topic, the likely impact of a molecular taxonomic of interstitial lung disease subgroups based upon gene expression profiling is discussed.     

Gene expression profile related to prognosis of acute myeloid leukemia

Acute myeloid leukemia (AML) is a heterogeneous group of diseases with respect to biology and clinical course. Through genome-wide scanning, we can have an improvement of the diagnosis and assay system of AML. Microarray was performed for the identification of acute myeloid leukemia prognosis. We divided patients into two groups (good prognosis group, GPG and poor prognosis group, PPG) based on differences in the individual reactions to treatment. Gene expression profiles were analyzed using microarray. Among genes up-regulated at least two-fold and down-regulated at least 0.5-fold in HL-60, we chose three up-regulated genes (PPP2CA, ME3, and CCDN2) and three down-regulated genes (GLO1, ANXA2, and BMI1) and confirmed the expression of these six genes by RT-PCR. We created a leukemia-specific subclass microarray, based on the gene expression profiles. Clinical samples from the bone marrow of four patients were hybridized on this microarray. Among the genes selected by the microarray technology, NB4, silenced TRIB3 and overexpressed XRN2 were not differentiated in spite of treatment with ATRA. This indicates that XRN2 and TRIB3 play an important role in cell differentiation. These data provided an expression profile for the diagnosis and prognosis of AML patients and identified candidate genes that might allow the prognosis of AML through the relative comparison of the expression level of genes between GPG and PPG.     

Mammary tumor induction in transgenic mice expressing an RNA-binding protein

We have analyzed mammary tumors arising in transgenic mice expressing a novel, multifunctional RNA-binding protein. The protein, which we call the c-myc mRNA coding region instability determinant binding protein (CRD-BP), binds to c-myc, insulin-like growth factor II, and beta-actin mRNAs, and to H19 RNA. Depending on the RNA substrate, the CRD-BP affects RNA localization, translation, or stability. CRD-BP levels are high during fetal development but low or undetectable in normal adult tissues. The CRD-BP is linked to tumorigenesis, because its expression is reactivated in some adult human breast, colon, and lung tumors. These data suggest the CRD-BP is a proto-oncogene. To test this idea, the CRD-BP was expressed from the whey acidic protein (WAP) promoter in mammary epithelial cells of adult transgenic mice. The incidence of mammary tumors was 95% and 60% in two lines of WAP-CRD-BP mice with high and low relative CRD-BP expression, respectively. Some of the tumors metastasized. Nontransgenic mice did not develop mammary tumors. H19 RNA and insulin-like growth factor II mRNA were up-regulated significantly in non-neoplastic WAP-CRD-BP mammary tissue. WAP-CRD-BP mice are a novel model for mammary neoplasia and might provide insights into human breast cancer biology.     

Gene expression profile as a prognostic factor in high-grade gliomas

Some clinical factors have been useful in predicting prognosis in high-grade gliomas, however, unexpected differences in survival time have generated attempts to search for more precise parameters. It is clear that tumour behaviour depends mostly on gene alterations. Known single gene alterations failed to accurately define survival time, however, recently, the gene profiling based on microarray technology has raised hopes. Our aim was to assess whether the genetic predictor exceeds clinical parameters in the prognosis of malignant gliomas. We performed gene expression analysis of 28 gliomas (3 grade II, 10 grade III and 15 grade IV, according to WHO classification), and 5 control, normal brain samples, using Clontech oligonucleotide arrays with 3,757 known genes. The signal-to-noise statistics was used to separate classes, and the leave-one-out method was used to assess the smallest number of genes make it clear with a minimal cross-validation error. All gliomas, or only high-grade tumours, were clearly separated from the normal brain samples using 7 or 9 most differentially expressed genes. Hierarchical clustering failed, but the fuzzy c-means method was useful in high-grade gliomas to find a gene prediction model, which, with clinical factors, was assessed in survival analysis. Univariate analysis demonstrated that age, WHO grade (IV vs. III), radiation dose (> or = 50 Gy vs. 42 Gy), postoperative KPS score (100 points vs. others), neurological deficit as the first sign of the disease vs. others, and gene expression profile were significant predictors of survival. In multivariate analysis, the gene expression profile remained the only independent predictor (p = 0.007). Thus, our conclusion is that gene expression pattern predicts outcome in high-grade gliomas independently of other factors.     

Polyomavirus large T-antigen expression in heart of transgenic mice causes cardiomyopathy

One of the early genes of polyomavirus, large T-antigen (PVLT), has been classified in vitro as an immortalizing gene. In order to determine the ability of PVLT to cause the formation of hyperplasia or tumors in vivo, we generated transgenic mice harboring the cDNA for PVLT linked to the heavy-metal responsive metallothionein-1 promoter (MT). The transgene was primarily expressed in testes and seminal vesicles, but expression was also detected in heart of a single transgenic line. The expression of the transgene in the heart of MT-PVLT line 8 mice was correlated with cardiomyopathy and atrial thrombus formation leading to premature death at approximately 160 days due to cardiac failure. The heart of affected animals was from 1.5 to 5.2 fold greater in weight and 2 fold greater in dimensions than normal nontransgenic mice. Affected hearts fell short of frank tumor phenotype and no macroscopic nor microscopic focal growth was found. Histologically the heart has a heterogenous cardiomyocyte population with markedly enlarged cells mixed with relatively normal cells. Both cell types express PVLT protein. The primary cell type affected is the cardiomyocyte however, as heart proportions are maintained, interstitial and non-myocyte cells must be affected either directly or indirectly. Expression of PVLT has upset normal strict control of cell growth in these hearts to result in a new model of congestive cardiomyopathy.