265 DICER GENE EXPRESSION IN PRE-IMPLANTATION MOUSE EMBRYOS: IMPLICATION OF TRANSCRIPTION REGULATION AT THE BLASTOCYST STAGE

2007 ◽  
Vol 19 (1) ◽  
pp. 249
Author(s):  
X. S. Cui ◽  
X. H. Shen ◽  
X. Y. Li ◽  
J. M. Kim ◽  
N. H. Kim
Keyword(s):  
Gene Expression ◽  
Protein Synthesis ◽  
Transcription Factors ◽  
Real Time ◽  
Expression Profiles ◽  
Blastocyst Stage ◽  
Rt Pcr ◽  
Expression Levels ◽  
Mouse Oocytes ◽  
Stage Embryo

Dicer is an RNAse III enzyme that is related to the generation of the microRNAs involved in the gene silencing pathway. In order to obtain insight into the role of Dicer in early embryo development, we first evaluated its gene expression levels in mouse oocytes and embryos during in vitro development. The relative abundance of Dicer1 transcripts was established by real-time RT-PCR using the 2-ddCt method. H2a was applied as an internal standard to normalize the real-time RT-PCR reaction efficiency and quantify Dicer1 mRNA. Relatively high expression levels of mRNA in germinal vesicle-stage oocytes steadily decreased up to the 2-cell stage embryo, and then expression remained during morulae and blastocyst formation. Protein synthesis of Dicer was also observed in the mouse oocytes and early embryos. Specific silencing of mRNA expression and protein synthesis by RNA interference (siRNA) did not inhibit developmental events up to the blastocyst (BL) stage. However, Dicer1 siRNA reduced (P <0.05) total nuclei numbers in the BL-stage embryos (Dicer1: 77.2�4.2 vs. control: 62.7�3.1). Real-time RT-PCR also confirmed that, following Dicer1 siRNA microinjection into zygotes, transcription levels of several non-target genes, Cdc42, Cdh1, Dbc2, ILK, Tuba1, Plat, and Tie1, were not changed in blastocyst-stage embryos. However, selected transcription factors, Pou5f1 (P <0.01), Nanog (P <0.005), and Sox2 (P <0.01), in blastocysts were significantly down-regulated. Additionally, POU5F1 protein synthesis was also reduced. Using Applied Biosystem microarray technology, we compared gene expression profiles in control and Dicer1 siRNA microinjected blastocysts. This technique confirmed that 397 or 737 of 16354 genes were up- or down-regulated, respectively, following siRNA microinjection (P <0.05), including 52 transcription factors. The results suggest that expression of Dicer regulates gene expression at the blastocyst-stage embryo for cell fate, possibly by the transcription control.

scholarly journals Monitoring gene expression changes in bovine oviduct epithelial cells during the oestrous cycle

2004 ◽  
Vol 32 (2) ◽  
pp. 449-466 ◽  
Author(s):  
S Bauersachs ◽  
S Rehfeld ◽  
SE Ulbrich ◽  
S Mallok ◽  
K Prelle ◽  
...  
Keyword(s):  
Gene Expression ◽  
Epithelial Cells ◽  
Expression Profiles ◽  
Cdna Array ◽  
Oestrous Cycle ◽  
Cdna Clones ◽  
Rt Pcr ◽  
Expression Levels ◽  
Starting Point ◽  
Oviduct Epithelial Cells

The oviduct epithelium undergoes marked morphological and functional changes during the oestrous cycle. To study these changes at the level of the transcriptome we did a systematic gene expression analysis of bovine oviduct epithelial cells at oestrus and dioestrus using a combination of subtracted cDNA libraries and cDNA array hybridisation. A total of 3072 cDNA clones of two subtracted libraries were analysed by array hybridisation with cDNA probes derived from six cyclic heifers, three of them slaughtered at oestrus and three at dioestrus. Sequencing of cDNAs showing significant differences in their expression levels revealed 77 different cDNAs. Thirty-seven were expressed at a higher level at oestrus, for the other 40 genes expression levels were higher at dioestrus. The identified genes represented a variety of functional classes. During oestrus especially genes involved in the regulation of protein secretion and protein modification, and mRNAs of secreted proteins, were up-regulated, whereas during dioestrus particularly transcripts of genes involved in transcription regulation showed a slight up-regulation. The concentrations of seven selected transcripts were quantified by real-time RT-PCR to validate the cDNA array hybridisation data. For all seven transcripts, RT-PCR results were in excellent correlation (r>0.92) with the results obtained by array hybridisation. Our study is the first to analyse changes in gene expression profiles of bovine oviduct epithelial cells during different stages of the oestrous cycle, providing a starting point for the clarification of the key transcriptome changes in these cells.

410. Gene expression analysis in endometriotic lesions using laser capture microdissection

2008 ◽  
Vol 20 (9) ◽  
pp. 90
Author(s):  
L. Fu ◽  
J. E. Girling ◽  
P. A. W. Rogers
Keyword(s):  
Gene Expression ◽  
Real Time ◽  
Laser Capture Microdissection ◽  
Stromal Cells ◽  
Expression Profiles ◽  
Specific Gene ◽  
Rt Pcr ◽  
Normal Endometrium ◽  
Rna Quality ◽  
Laser Capture

Previous studies examining gene expression profiles in normal endometrium and endometriotic lesions have used RNA extracted from whole tissue samples. Results from these studies can be difficult to interpret as they reflect expression averaged across several different cell types that may be functionally quite different. The aim of this study was to establish laser capture microdissection (LCM) as a technique to examine gene expression in stromal and epithelial cells from normal and ectopic endometrium. We hypothesised that genes associated with inflammation would be elevated in cells from endometriotic lesions. Full thickness uterine samples were collected during abdominal hysterectomy from normal cycling premenopausal women. Endometriotic lesions were collected during abdominal laparoscopy. Samples were either frozen in OCT or stored in RNAlater for 12 h before freezing. Tissues were immunostained with an antibody against CD10 to identify ectopic endometrial stromal cells before LCM. Endometrial epithelial and stromal cells were collected using the PALM MicroLaser System. RNA quality was accessed using Experion. TGFβ1, MMP1, αSMA, SMAD2 and NFκB mRNA was analysed using real-time RT–PCR. Of the endometriotic samples stored in OCT (n = 58), only 14% (n = 8) had visible endometrial glands. Of these, only 37% (n = 3) had RNA of an acceptable quality for further analysis. However, RNA quality and quantity were dramatically improved in 3 of 5 samples collected in RNAlater. In preliminary studies, expression of TGFβ1 and αSMA mRNA was elevated in endometriotic lesions in comparison to the normal endometrium, whereas NFκB expression did not change. We have shown that RNAlater solution is useful to preserve RNA quality for small clinical endometriotic samples and that immuno-guided LCM-generated homogenous cell populations coupled with real-time RT–PCR can provide valuable insights into cell and disease-specific gene expression in endometriotic lesions.

Identification of Angiogenesis/Metastases Genes Predicting Chemoradiotherapy Response in Patients With Laryngopharyngeal Carcinoma

2007 ◽  
Vol 25 (11) ◽  
pp. 1369-1376 ◽  
Author(s):  
Ian Ganly ◽  
Simon Talbot ◽  
Diane Carlson ◽  
Agnes Viale ◽  
Ellie Maghami ◽  
...  
Keyword(s):  
Gene Expression ◽  
Real Time ◽  
Cdna Microarray ◽  
Expression Profiles ◽  
External Validation ◽  
Cdna Array ◽  
Disease Free Survival ◽  
Independent Set ◽  
Rt Pcr ◽  
Locoregional Failure

Purpose To identify genes related to angiogenesis/metastasis that predict locoregional failure in patients with laryngopharyngeal cancer (LPC) undergoing chemoradiotherapy (CRT) treatment. Methods Tumor tissue was collected and snap-frozen from 35 sequential patients with histologically confirmed LPC being treated with CRT. Gene expression analysis was performed using a novel cDNA array consisting of 277 genes functionally associated with angiogenesis (n = 152) and/or metastasis (n = 125). Locoregional response was correlated to the gene expression profiles to identify genes associated with outcome. These genes were internally validated by real-time reverse transcriptase polymerase chain reaction (RT-PCR) and validated externally by immunohistochemistry analysis on an independent set of patients. Results Locoregional failure occurred in nine of 35 patients. Seventeen genes from the cDNA microarray correlated with locoregional failure (two-sample t test, P < .05). Seven genes were chosen for additional analysis based on the availability of antibodies for immunohistochemistry. Of these seven genes, real-time RT-PCR validated four genes: MDM2, VCAM-1, erbB2, and H-ras (Wilcoxon rank sum test, P = .008, .02, .04, and .04, respectively). External validation by immunohistochemistry confirmed MDM2 and erbB2 as being predictive of locoregional response. Controlling for stage of disease, positivity for MDM2 or erbB2 was an independent negative predictor of locoregional disease-free survival. Conclusion Genomic screening by cDNA microarray and validation internally by real-time RT-PCR and externally by immunohistochemistry have identified two genes (MDM2 and erbB2) as predictors of locoregional failure in LPC patients treated with CRT. The role of these genes in treatment selection and the functional basis for their activity in CRT response merit additional consideration.

194 HOUSEKEEPING GENE EXPRESSION OF BOVINE FERTILIZED AND CLONED EMBRYOS

2009 ◽  
Vol 21 (1) ◽  
pp. 195 ◽  
Author(s):  
P. J. Ross ◽  
K. Wang ◽  
Z. Beyhan ◽  
A. Kocabas ◽  
J. B. Cibelli
Keyword(s):  
Gene Expression ◽  
Real Time ◽  
18S Rrna ◽  
Cyclophilin A ◽  
Housekeeping Genes ◽  
Housekeeping Gene ◽  
Blastocyst Stage ◽  
Histone H2a ◽  
Cell Stage ◽  
Expression Levels

Real-time RT-PCR can accurately quantify mRNA levels in pre-implantation embryos; however, comparisons among different embryonic stages and among embryos produced by different means often rely on a control gene, which is commonly assumed to remain constant across samples. The objective of this study was to compare housekeeping gene expression levels, relative to total mRNA, across different stages of bovine pre-implantation development in embryos generated by IVF and somatic cell nuclear transfer (SCNT). Embryos were produced according to standard protocols (Ross et al. 2006 Biotechniques 41, 741–750). Total RNA was collected from 3 pools of 10 oocyte/embryos at metaphase II (MII), PN, 2-cell, 4-cell, 8-cell, morula, and blastocyst stages and reverse-transcribed using oligo-dT primers. The cDNA was then amplified using PCR (Kocabas et al. 2006 PNAS 103, 14 027–14 032). All amplified cDNA samples were diluted to 1 ng μL–1, as determined by NanoDrop spectrophotometer (Thermo Fisher Scientific, Wilmington, DE, USA) and corroborated using a Qubit fluorometer (Invitrogen, Carlsbad, CA, USA). For real-time PCR, 2 μL of cDNA was analyzed in duplicates. Absolute quantification was performed as previously described (Iager et al. 2008 Cloning Stem Cells doi:10.1089), using SYBR-green chemistry and standard curves specific for each gene. The number of RNA copies per nanogram of amplified cDNA was compared among samples using ANOVA. Glyceraldehyde 3-phosphate dehydrogenase (GAPDH), cyclophilin A, β-actin, ribosomal protein L-15 (RPL-15), and β-glucuronidase (GUS) expression levels were similar in MII oocyte, 1-, 2-, 4-, and 8-cell embryos, while a significant increase at morula and blastocyst stages was observed (P < 0.05). A similar pattern of expression was observed for 18S ribosomal RNA, but with a significant decrease from morula to blastocyst stages (P < 0.05). Histone H2A expression was significantly higher at 1-cell stage, similar from 2-cell to morula stages and lowest at the blastocyst stage. We then compared expression between IVF and SCNT embryos at 2-, 4-, and 8-cell and blastocyst stages. GAPDH, RPL-15, GUS, and β-actin were significantly different among groups in at least 3 of the analyzed stages, which in all cases included blastocysts. 18s-rRNA was different among IVF and SCNT embryos only at the 8-cell stage, while no differences were observed at any stages for histone H2A and cyclophilin A. At the blastocyst stage, the lowest overall variability among IVF and SCNT embryos was observed for 18s-rRNA. In conclusion, none of the evaluated housekeeping genes showed consistent mRNA expression levels across developmental stages of IVF embryos. In addition, SCNT embryos, compared to IVF, had different levels of gene expression for commonly used housekeeping genes, which, if neglected, might result in data misinterpretation. In our conditions, histone H2A had similar expression levels between IVF and SCNT embryos across different stages and showed less variability than cyclophilin A. Finally, for comparisons at the blastocyst stage, 18s-rRNA had the least variability among IVF and SCNT embryos.

NFκB-Mediated Up-Regulation of Transcription Factors Related to More Primitive State of Hematopoietic Progenitor Cells.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 1246-1246
Author(s):  
Rodrigo A. Panepucci ◽  
Lucila H.B. Oliveira ◽  
Dalila L. Zanette ◽  
Greice A. Molfetta ◽  
Rita C.V. Carrara ◽  
...  
Keyword(s):  
Gene Expression ◽  
Transcription Factors ◽  
Progenitor Cells ◽  
Real Time ◽  
Quantitative Pcr ◽  
Expression Profiles ◽  
Hematopoietic Progenitor Cells ◽  
Hematopoietic Progenitor ◽  
Cd34 Cells ◽  
Primitive State

Abstract We have previously shown that a distinctive feature of umbilical cord blood (UCB) CD34+ hematopoietic progenitor cells (HSPC) as compared to bone marrow (BM) CD34+ is a higher expression of transcription targets and components of the nuclear factor kappa B (NF-κB) pathway. NFKB2 and RELB are sub-units of the transcription factor (TF) that specifically mediates the constitutive NF-κB signaling pathway and their increased levels could be related with the primitive state of the newborn’s HSPC. However, BM and UCB CD34+ HSPC differ in their sub-population compositions, and a higher proportion of more primitive cells among the CD34+ cells could account for those differences. CD133 is a surface marker expressed on a more primitive sub-population of CD34+ cells that are highly enriched in long-term culture-initiating cells, NOD/SCID-repopulating cells. We used flow cytometry, oligonucleotide microarray gene expression profiling and real time quantitative PCR to better characterize immunomagnetically sorted CD34+ and CD133+ HSPC derived from BM and UCB. We found that UCB CD34+ cells contain a larger proportion of CD133+ cells (around 70%), differing from BM CD34+ cells (around 30%). Cluster analysis of the expression profiles, encompassing 10.000 genes, showed that UCB CD133+ are more similar to UCB CD34+ than to BM CD133+ cells. Furthermore, a statistically significant higher expression of NFKB2 and RELB was demonstrated by quantitative PCR on UCB CD133+ HSPC, compared to BM. Overall this indicates that despite distinct compositions of the cells from UCB or BM, UCB HSPC display intrinsic molecular differences related to their ontological age. The comparison of the gene expression profiles of the CD133+ with the CD34+ populations revealed the higher expression of many well known factors related to more primitive HSPC and hemangioblasts. In fact, TFs such as RUNX1/AML1, GATA3, USF1, TAL1/SCL, HOXA9 and HOXB4 were all present at higher levels in CD133+ HSPC. In an attempt to identify a key TF that could be responsible for the expression of these important factors, we carried a promoter analysis for the set of highly expressed TF found in the CD133 cells. A frequency of TF binding sites significantly higher than the expected was observed for the NF-κB TFs, including potential NF-κB targets such as RUNX1, GATA3 and USF1. Measurements of GATA3, NFKB2 and RELB expression by real-time PCR showed a higher expression of the three genes in CD133+ samples (both from BM and UCB), as well as a correlation of the expression levels of NFkB2 and RELB with one another and with GATA3 (Sperman’s correlation), indicating that GATA3 could be, in fact, regulated by NF-κB. To further test this hypothesis, we used interference RNA (RNAi) against NFKB2 in HSPC. Levels of NFKB2, GATA3 and RELB (a known target of NFKB2/RELB dimmers) were down-modulated, in comparison with cells transfected with control RNAi. Taken together, our data indicates that constitutive NF-κB signaling may act up-regulating transcription factors related to a more primitive state of HSPC.

Gene Expression Profiling and Real-Time PCR Analyses Make It Possible To Identify Novel Potential Cancer-Testis Antigens in Multiple Myeloma.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 1793-1793
Author(s):  
Maud Condomines ◽  
Dirk Hose ◽  
Thierry Reme ◽  
John de Vos ◽  
Guilhem Requirand ◽  
...  
Keyword(s):  
Gene Expression ◽  
Multiple Myeloma ◽  
Real Time ◽  
Expression Profiles ◽  
Differentially Expressed ◽  
Rt Pcr ◽  
Normal Tissues ◽  
Present Call ◽  
The Mean ◽  
Cancer Testis

Abstract The identification of novel tumor-associated antigens is critical for the development of immunotherapeutic strategies. Cancer-testis (CT) antigens represent attractive targets due to their restricted pattern of expression. More than 90 CT genes have been previously classified into four categories according to their expression profiles: testis-restricted (expression in testis and tumor samples only), “tissue restricted” (mRNA detected in 2 or fewer non-gametogenic tissues), “differentially expressed” (mRNA detected in three to six non-gametogenic tissues), and “ubiquitously expressed”. Among those, we previously reported that 18 CT genes were expressed by primary myeloma cells (MMC) of more than 10% of patients with multiple myeloma (MM). This study aimed at finding novel putative CT genes expressed in MM using cDNA microarray analysis and real-time RT-PCR validation. Gene expression profiles of 5 testis samples, 64 MMC, 7 normal memory B cell (MB), 7 normal bone marrow plasma cell samples and 23 normal tissue samples available on a public database were obtained using Affymetrix U133AB microarrays. Out of 45000 probe sets of Affymetrix U133 AB chips, we selected 16982 probe sets which had a “Present” Affymetrix Call in MMC of at least 6/64 patients and in 3/5 testis samples. In order to select genes with a similar pattern of expression than the known CT genes, we developed 4 independent filters making it possible to keep a high number of known CT genes while decreasing the total number of probe sets. Firstly, 2514 of 16982 probe sets had a ratio of the mean signal in MMC with a Present call / mean signal in MB &gt; 2.5. Secondly, 541 of these 2514 probe sets had a Present call in less than 7 of the 23 normal tissues. Thirdly, 333 of these 541 probe sets had a ratio of the mean signal in MMC with a Present call / mean signal in MMC with an Absent call &gt; 2.5. Fourthly, we removed genes whose expression profiles were discordant with different probe sets or discordant with data of the literature. The final probe set list contains 88 probe sets which include 13 of 18 known CT genes reported in MM, thus resulting in a 190-fold enrichment. The expression in 13 normal tissues and in MM samples of 21 out of these 75 putative novel CT genes was investigated by real time RT-PCR. Seven genes were ubiquitously expressed or poorly expressed in MMC samples and further deleted. According to the previously defined CT gene categories, we found one novel “testis-restricted” (TEX14), 8 “tissue-restricted” and 5 “differentially expressed” CT genes. Immunogenicity of one gene product - IGSF11 - was already demonstrated in other cancers by identifying a T-cell epitope. Two genes - NLGN4X and FAM133A - are located in X chromosome and 2 genes - CTNNA2 and FAM133A - are expressed only in brain and testis. In conclusion, by analyzing gene expression patterns with Affymetrix microarrays, we found 75 novel putative CT antigen candidates expressed in MMC of 10 to 100% of patients. Real time RT-PCR validation made it possible to confirm the CT status of 14 genes out of the 21 tested. Further studies are warranted to determine their immunogenicity.

Novel blood biomarker panel detects human colorectal cancer

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 3611-3611
Author(s):  
M. Han ◽  
C. T. Liew ◽  
H. W. Zhang ◽  
K. T. Yip ◽  
Z. Y. Song ◽  
...  
Keyword(s):  
Gene Expression ◽  
Colorectal Cancer ◽  
B Cell ◽  
Real Time ◽  
Cytidine Deaminase ◽  
Expression Profiles ◽  
The United States ◽  
Rt Pcr ◽  
Human Colorectal Cancer ◽  
Blind Test

3611 Background: Human colorectal cancer (CRC) is the second leading cause of cancer-related death in the United States, and early detection is critical to improve prognosis. To date, we have applied our unique methodology (the Sentinel Principle) to identify blood-based gene expressed biomarkers for several diseases including osteoarthritis, bladder cancer and psychiatric disorders. In the present CRC study, we identified gene signatures from blood cells and characterized a set of biomarkers able to differentiate patients with CRC from controls. Methods: Microarray: 31 blood RNA sample (15 controls; 16 CRC) were profiled using Affymetrix U133Plus2.0 GeneChips. Differentially expressed genes were identified using the non-parametric, Wilcoxon-Mann-Whitney test. SYBR Green real-time RT-PCR: a subset of identified genes was assayed using 115 samples (57 controls; 58 CRC). Logistic regression was used to assess the ability of linear combinations of specific transcripts to distinguish CRC from controls. The diagnostic power for each combination was evaluated by AUC of the Receiver Operating Characteristic (ROC) curve. Blind Test: 83 samples were assayed (45 controls and 38 CRC). Results: Microarray data: 2,779 probes were significantly different in blood gene expression profiles from controls and those from CRC (p<0.05). Real-time RT-PCR: Two up-regulated genes (cytidine deaminase, 1.3 fold with p<0.001; MGC20553 /FERM domain containing 3, 1.2 fold with p=0.031) and three down-regulated genes were validated (B-cell scaffold protein with ankyrin repeats 1, 0.43 fold with p<0.001; B-cell novel protein 1, 0.44 fold with p<0.001; membrane-spanning 4-domains, subfamily A, member 1, 0.44 with p<0.001). Combination analysis: The AUC was 0.883 (95%, C.I. 0.810–0.935) for the best linear combination of these 5 genes. At a cut-off of -1.1, the sensitivity and specificity were 98% and 51%, respectively. Blind Test: The 5-gene set gave sensitivity of 95% (36/38) and specificity of 42% (19/45) with an overall accuracy of 66%. Conclusions: Gene expression signatures from peripheral blood differentiate between CRC patients and controls. The five-gene panel showed high classification performance and could be used as a novel screening tool for CRC. [Table: see text]

Evaluation of 5-FU metabolism-relating enzyme gene expression levels using quantitative real-time RT-PCR from formalin fixed parafine embedded samples

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 13034-13034
Author(s):  
M. Terashima ◽  
Y. Odashima ◽  
S. Ohtani ◽  
N. Soeta ◽  
F. Ohsuka ◽  
...  
Keyword(s):  
Gene Expression ◽  
Colorectal Cancer ◽  
Real Time ◽  
Clinical Settings ◽  
Rt Pcr ◽  
Expression Levels ◽  
Ffpe Samples ◽  
Fresh Frozen ◽  
Gene Expression Levels

13034 Background: We have previously reported that tumors with high orotate phosphoribosil transferase (OPRT) and low dihydropyrimidine dehydrogenase (DPD) mRNA expression levels showed remarkable sensitivity to 5-fluorouracil (5-FU) by real-time RT-PCR using fresh frozen (FF) tumor samples. However, the use of fresh frozen samples has some limitations. The use of formalin fixed parafine embedded (FFPE) samples has great advantage to apply these technologies for clinical settings. In order to investigate the feasibility of real-time RT-PCR from FFPE samples to predict sensitivitiy to 5-fluorouracil (5-FU), we investigated the gene expression levels of 5-FU metabolism-relating enzymes by real-time RT-PCR from FFPE samples and compared the results from FF samples in gastric and colorectal cancer. Methods: FFPE samples and FF samples were obtained from 46 patients with gastric cancer and 29 patients with colorectal cancer. Gene expression levels of tymidylate synthase (TS), OPRT, thymidine phosphorylase (TP) and DPD were determined by quantitative real-time RT-PCR. In FFPE samples tumor tissue was obtained using laser captured microdissection (LCM). Tumor sensitivity to 5-FU was evaluated by in vitro ATP assay. Results: Gene expression levels of TS, TP, DPD determined from FFPE samples significantly correlated with those from FF samples. Although respective gene expression levels alone failed to show signifcianct correlation with the in vitro 5-FU sensitivity, statistically significant correlation was noted either from the samples of FF or FFPE in both gastric (FF: r = 0.660, FFPE: r = 0.780) and colorectal cancer (FF: r = 0.780, FFPE: r = 0.660), when OPRT/DPD mRNA ratio was applied for comparison with the results of 5-FU sensitivity. Thus, high OPRT/DPD ratio determined from FFPE samples resulted in high sensitivity to 5-FU. Conclusions: From these results, it is suggested that sensitivity to 5-FU is predictable by quantitative RT-PCR using FFPE samples. Measurement of 5-FU metabolism-relating enzyme gene expression level from FFPE samples appeared to be feasible for predicting 5-FU sensitivity and to have great advantage to apply the molecular predicting assay in clinical settings. [Table: see text]

scholarly journals Group A Streptococcus Gene Expression in Humans and Cynomolgus Macaques with Acute Pharyngitis

2003 ◽  
Vol 71 (4) ◽  
pp. 2199-2207 ◽  
Author(s):  
Kimmo Virtaneva ◽  
Morag R. Graham ◽  
Stephen F. Porcella ◽  
Nancy P. Hoe ◽  
Hua Su ◽  
...  
Keyword(s):  
Gene Expression ◽  
Real Time ◽  
Pediatric Patients ◽  
Throat Swab ◽  
Expression Profiles ◽  
Rt Pcr ◽  
Acute Pharyngitis ◽  
Cynomolgus Macaques ◽  
Group A

ABSTRACT The molecular mechanisms used by group A Streptococcus (GAS) to survive on the host mucosal surface and cause acute pharyngitis are poorly understood. To provide new information about GAS host-pathogen interactions, we used real-time reverse transcription-PCR (RT-PCR) to analyze transcripts of 17 GAS genes in throat swab specimens taken from 18 pediatric patients with pharyngitis. The expression of known and putative virulence genes and regulatory genes (including genes in seven two-component regulatory systems) was studied. Several known and previously uncharacterized GAS virulence gene regulators were highly expressed compared to the constitutively expressed control gene proS. To examine in vivo gene transcription in a controlled setting, three cynomolgus macaques were infected with strain MGAS5005, an organism that is genetically representative of most serotype M1 strains recovered from pharyngitis and invasive disease episodes in North America and Western Europe. These three animals developed clinical signs and symptoms of GAS pharyngitis and seroconverted to several GAS extracellular proteins. Real-time RT-PCR analysis of throat swab material collected at intervals throughout a 12-day infection protocol indicated that expression profiles of a subset of GAS genes accurately reflected the profiles observed in the human pediatric patients. The results of our study demonstrate that analysis of in vivo GAS gene expression is feasible in throat swab specimens obtained from infected human and nonhuman primates. In addition, we conclude that the cynomolgus macaque is a useful nonhuman primate model for the study of molecular events contributing to acute pharyngitis caused by GAS.

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