Quantitative Reverse Transcription-polymerase Chain Reaction (quantitative + reverse_transcription-polymerase_chain_reaction)

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Distribution within Medical Sciences

Terms modified by Quantitative Reverse Transcription-polymerase Chain Reaction

  • quantitative reverse transcription-polymerase chain reaction analysis

  • Selected Abstracts


    DNA methylation and histone modification regulate silencing of OPG during tumor progression,

    JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 1 2009
    Tung-Ying Lu
    Abstract The identification of molecules that are down-regulated in malignant phenotype is important for understanding tumor biology and their role in tumor suppression. We compared the expression profile of four normal nasal mucosal (NNM) epithelia and a series of nasopharyngeal cancinoma (NPC) cell lines using cDNA microarray and confirmed the actual expression of the selected genes, and found osteoprotegerin (OPG) to be ubiquitously deficient in NPC cells. We also found OPG to be down-regulated in various cancer cell lines, including oral, cervical, ovarian, lung, breast, pancreas, colon, renal, prostate cancer, and hepatoma. Administration of recombinant OPG (rOPG) brought about a reduction in cancer cell growth through apoptotic mechanism. We generated eleven monoclonal antibodies (MAbs) against OPG to study OPG's expression and biological functions in cancer cells. OPG was detected in the tumor stromal regions, but not in the cancer cell per se in surgical specimens of liver cancer. Quantitative reverse transcription-polymerase chain reaction (Q-RT-PCR) revealed that OPG was down-regulated in NPC tissues compared with normal nasal polyp (NNP) tissues. In addition, we showed OPG silencing to be associated with promoter methylation as well as histone modifications. In OPG-silenced cancer cell lines, the OPG gene promoter CpG dinucleotides were highly methylated. Compared to normal cells, silenced OPG gene in cancer cells were found to have reduced histone 3 lysine 4 tri-methylation (H3K4me3) and increased histone 3 lysine 27 tri-methylation (H3K27me3). Taken together, these results suggest that OPG silencing in carcinoma cancer cells occurs through epigenetic repression. J. Cell. Biochem. 108: 315,325, 2009. © 2009 Wiley-Liss, Inc. [source]


    Dystrophin upregulation in pressure-overloaded cardiac hypertrophy in rats

    CYTOSKELETON, Issue 1 2003
    Masato Maeda
    Abstract Dystrophin is a cytoskeletal protein localized to the sarcolemma of skeletal and cardiac muscle, and neurons. We have recently demonstrated that a significant cardiac damage including myocytes injury, inflammation, and fibrosis, was found in dystrophin-deficient myocardium during pressure overload [Kamogawa et al., 2001: Cardiovasc Res 50:509,515]. However, little is known about how the cardiac sarcolemmal cytoskeleton produces qualitative and quantitative changes in response to pressure overload. Accordingly, we investigated dystrophin gene expression and protein accumulation during cardiac hypertrophy. Cardiac hypertrophy was produced by banding of the abdominal aorta of rats. Total RNA from the left ventricle of the heart was used for a quantitative reverse transcription-polymerase chain reaction (RT-PCR). Dystrophin mRNA expression significantly increased by 33 ± 18% at 1 day (P < 0.05) and 45 ± 19% at 2 days (P < 0.01) after banding, while G3PDH mRNA showed no significant change. RT-PCR for dystrophin tissue-specific exon 1 revealed that only muscle type promoter, but not non-muscle type promoter (brain and Purkinje-cell type), was activated immediately after banding. Immunohistochemistry for dystrophin showed intense cellular membrane staining with an increase in the perimeter of the myocytes by 14% at 3 days (46.3 ,m, P < 0.01) and 19% at 7 days (51.2 ,m, P < 0.01) after banding. Western blotting also showed dystrophin protein increased by 14 ± 6% at 2 days (P < 0.05) and by 32 ± 10% at 3 days (P < 0.01) after aortic banding. In conclusion, upregulation of dystrophin mRNA expression and protein accumulation occurs in response to cardiac hypertrophy. These data and the vulnerability of dystrophin-deficient myocardium to pressure overload suggest that dystrophin could play an important role in maintaining the integrity of the sarcolemma. Cell Motil. Cytoskeleton 55:26,35, 2003. © 2003 Wiley-Liss, Inc. [source]


    Impact of microcystin containing diets on physiological performance of Nile tilapia (Oreochromis niloticus) concerning stress and growth,

    ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 3 2010
    Andrea Ziková
    Abstract Diets containing Microcystis with considerable amounts of the cyanotoxin microcystin-LR (MC-LR) were fed to determine their impact on the physiological performance of the omnivorous Nile tilapia (Oreochromis niloticus) with regard to stress and growth performance. Four different diets were prepared based on a commercial diet (control, MC-5% [containing 5% dried Microcystis biomass], MC-20% [containing 20% dried Microcystis biomass], and Arthrospira-20% [containing 20% dried Arthrospira sp. biomass without toxin]) and fed to female Nile tilapia. Blood and tissue samples were taken after 1, 7, and 28 d, and MC-LR was quantified in gills, muscle, and liver by using high-performance liquid chromatography (HPLC). Only in the liver were moderate concentrations of MC-LR detected. The stress hormone cortisol and glucose were analyzed from plasma, suggesting that all modified diets caused only minor to moderate stress, which was confirmed by analyses of hepatic glycogen. In addition, the effects of the different diets on growth performance were investigated by determining gene expression of hypophyseal growth hormone (GH) and hepatic insulin-like growth factor-I (IGF-I). For all diets, quantitative reverse transcription-polymerase chain reaction (RT-qPCR) demonstrated no significant effect on gene expression of the major endocrine hormones of the growth axis, whereas classical growth data, including growth and feed conversion ratio, displayed slight inhibitory effects of all modified diets independent of their MC-LR content. However, no significant change was found in condition or hepatosomatic index among the various diets, so it seems feasible that dried cyanobacterial biomass might be even used as a component in fish diet for Nile tilapia, which requires further research in more detail. Environ. Toxicol. Chem. 2010;29:561,568. © 2009 SETAC [source]


    DNA demethylation of vascular endothelial growth factor-C is associated with gene expression and its possible involvement of lymphangiogenesis in gastric cancer

    INTERNATIONAL JOURNAL OF CANCER, Issue 8 2007
    Shunji Matsumura
    Abstract Previous studies have indicated that lymphangiogenesis in solid tumors is associated with lymphatic metastasis. Overexpression of Vascular endothelial growth factor (VEGF)-C plays a major role in lymphangiogenesis in cancers. In the present study, DNA methylation and expression of the VEGF-C gene was investigated in gastric cancer (GC). Four GC cell lines (MKN-45, MKN-74, HSC-39 and HSC-43) showed no expression of VEGF-C, and the VEGF-C gene was found to be methylated in these cells. In contrast, 7 GC cell lines (MKN-1, MKN-7, MKN-28, TMK-1, KATO-III, SH101-P4 and HSC-44PE) expressed VEGF-C, and the VEGF-C gene was found to be unmethylated in these cell lines. In addition, expression of VEGF-C mRNA was retrieved by treatment with a demethylating agent, Aza-2,-deoxycytidine. In GC tissue samples, bisulfite DNA sequencing analysis revealed that VEGF-C was not methylated in 9 (29.0%) of 31 GC samples, whereas demethylation was not observed in corresponding non-neoplastic mucosa samples. Overexpression of VEGF-C mRNA was observed in 16 (51.6%) of 31 GC samples by quantitative reverse transcription-polymerase chain reaction. Of the 9 GC cases with VEGF-C demethylation, 8 (88.9%) overexpressed VEGF-C. In contrast, of the 22 GC cases without VEGF-C demethylation, 8 (36.4%) overexpressed VEGF-C (p = 0.0155). Furthermore, lymphatic vessel density determined by immunostaining of podoplanin in GC tissues was associated with overexpression of VEGF-C (p < 0.0001). These results suggest that demethylation and activation of the VEGF-C gene is likely involved in lymphangiogenesis in GC. © 2007 Wiley-Liss, Inc. [source]


    Th2 polarization of the immune response of BALB/c mice to Ixodes ricinus instars, importance of several antigens in activation of specific Th2 subpopulations

    PARASITE IMMUNOLOGY, Issue 2 2001
    Naceur Mejri
    BALB/c mice were infested with Ixodes ricinus larvae, nymphs or adults. Expression of IL-4 and IFN-, mRNA in axillary and brachial draining lymph node cells were measured by competitive quantitative reverse transcription-polymerase chain reaction 9 days after the beginning of primary-infestation. IL-4 mRNA was always higher than that of IFN-, mRNA for all tick instars. Moreover, IL-4 mRNA expression progressively increased during nymphal primary-infestation with a high burst of expression 7 days after the beginning of infestation. No evolution of IFN-, mRNA expression was detected. Draining lymph node cells of infested BALB/c produced higher level of IL-4 than IFN-, following in vitro restimulation with adult tick saliva, salivary gland extract (SGE) or with five selected different chromatographic fractions of SGE. Anti-tick IgG1 antibodies but no IgG2a were detected in BALB/c pluri-infested with I. ricinus nymphs, which confirmed the Th2 polarization of the immune response. [source]


    Relative concentrations of hK2/PSA mRNA in benign and malignant prostatic tissue

    THE PROSTATE, Issue 4 2005
    Susanna Lintula
    Abstract BACKGROUND Prostate-specific antigen (PSA/KLK3) and human kallikrein 2 (hK2/KLK2) belong to the human kallikrein gene family. These two highly homologous genes are specifically expressed in the prostate under androgen control. Expression of these is regulated by similar mechanisms but changes in their relative expression have been observed in prostate cancer. METHODS We determined the relative levels of PSA and hK2 mRNA in benign and malignant prostate tissue using a quantitative reverse transcription-polymerase chain reaction (RT-PCR) method. The mRNA of PSA and hK2 are reverse transcribed and amplified in one reaction with the same primers. RESULTS The variation in the ratio of hK2/PSA mRNA was remarkably small, the difference between the highest and lowest values being three-fold. The ratio was significantly higher in WHO grade 2 compared to normal or benign prostatic hyperplasia tissue (P,=,0.032 and P,=,0.035, respectively) and in grade 3 compared to normal or benign prostatic hyperplasia tissue (P,=,0.006 in both). CONCLUSIONS The new quantitative RT-PCR technique facilitates very accurate quantitation of the relative mRNA levels of homologous genes. Using this method we have shown that the ratio of hK2/PSA mRNA is higher in cancerous than in benign prostatic tissue. © 2004 Wiley-Liss, Inc. [source]


    Differentially expressed transcripts in adipose tissue between Korean native pig and Yorkshire breeds

    ANIMAL GENETICS, Issue 1 2009
    J.-K. Moon
    Summary We measured and compared the transcripts of adipose tissue from Korean native pig (KNP) and Yorkshire (YS) breeds to investigate breed-specific transcription changes. We employed both the Affymetrix porcine genome array and quantitative reverse transcription-polymerase chain reaction (qRT-PCR). We found eight genes showing significant changes between the two breeds. Based on a literature review, these genes were indicative of differences in extracellular structure density and differences in the potential to metabolize xenobiotic chemicals and lipids. The differentially expressed genes indicated that KNP has a lower extracellular structure density and a lower potential to metabolize xenobiotic chemicals than YS. [source]


    Increased expression of epidermal fatty acid-binding protein by alveolar macrophages during acute rejection of rat lungs

    APMIS, Issue 10 2010
    JULIA HOLLER
    Holler J, Zakrzewicz A, Garn H, Hirschburger M, Kummer W, Padberg W, Grau V. Increased expression of epidermal fatty acid-binding protein by alveolar macrophages during acute rejection of rat lungs. APMIS 2010; 118: 791,800. In the lung, epidermal fatty acid-binding protein (E-FABP) is expressed by alveolar macrophages (AM) and alveolar epithelial cells type II (AEII). E-FABP may regulate macrophage activation and is involved in the metabolism of surfactant phospholipids. As macrophage activation and surfactant dysfunction are associated with rejection, we hypothesize that E-FABP expression is changed during acute rejection of pulmonary grafts. Orthotopic left lung transplantations were performed in the Dark Agouti to Lewis and in the isogeneic Lewis to Lewis rat strain combinations. E-FABP expression was analyzed in the lung by immunohistochemistry, immunoblotting and quantitative reverse transcription-polymerase chain reaction (RT-PCR). Alveolar leukocytes obtained by bronchoalveolar lavage were analyzed by RT-PCR. Immunohistochemistry of isografts revealed strong E-FABP immunoreactivity in AEII and a moderate immunoreactivity in AM. In allografts undergoing acute rejection, AM exhibiting increased E-FABP immunoreactivity accumulated. Immunoblots revealed a single band at 15 kDa, which corresponds to the expected molecular mass of E-FABP. The levels of E-FABP mRNA were higher in allografts than in isografts and control lungs. Furthermore, alveolar leukocytes isolated by bronchoalveolar lavage from allografts displayed higher E-FABP mRNA expression levels than leukocytes from isografts and controls. In conclusion, we demonstrate for the first time upregulation of E-FABP expression in AM during severe inflammation. [source]


    Increased expression of transient receptor potential vanilloid subfamily 1 in the bladder predicts the response to intravesical instillations of resiniferatoxin in patients with refractory idiopathic detrusor overactivity

    BJU INTERNATIONAL, Issue 5 2007
    Hsin-Tzu Liu
    OBJECTIVES To investigate the correlation of transient receptor potential vanilloid subfamily 1 (TRPV1) mRNA expression levels and the clinical outcome of intravesical resiniferatoxin treatment in patients with idiopathic detrusor overactivity (IDO), as such treatment with vanilloids can be effective for DO. PATIENTS AND METHODS In all, 28 patients with IDO refractory to anticholinergics were enrolled and treated with four weekly intravesical instillations of 10 nm resiniferatoxin. Eleven patients having ureteroscopic surgery served as controls. Two bladder wall biopsies were taken from the posterior wall by rigid cystoscopy. TRPV1 expression in the bladder wall samples was determined by individual quantitative reverse transcription-polymerase chain reaction, and immunohistochemical staining. Responders to the therapy were defined as those with an improvement in an urgency scale by ,1, and with improved general satisfaction. Baseline TRPV1 expression was compared between responders, nonresponders and controls. RESULTS At 3 months, 14 patients (50%) were responders and in the other 14 the treatment failed (nonresponders). Bladder biopsies were available in seven responders and 11 nonresponders. Transcript levels before treatment correlated significantly with the therapeutic effect of resiniferatoxin (P = 0.004), with higher TRPV1 mRNA expression in responders (median 1.50, range 0.89,2.78) than nonresponders (0.74, 0.34,1.32). Responders also had higher TRPV1 expression levels than a control group (P = 0.067), but the TRPV1 transcript levels of nonresponders were not significantly different from those of the control (P = 0.367). CONCLUSION Successful intravesical resiniferatoxin treatment is closely associated with the over-expression of TRPV1 in the bladder mucosa and submucosa in patients with IDO. [source]


    Different vascular endothelial growth factor (VEGF), VEGF-receptor 1 and -2 mRNA expression profiles between clear cell and papillary renal cell carcinoma

    BJU INTERNATIONAL, Issue 3 2006
    BÖRJE J. LJUNGBERG
    OBJECTIVES To examine vascular endothelial growth factor (VEGF), VEGF-receptor-(R)1, and R2 mRNA levels in renal cell carcinoma (RCC), a tumour generally refractory to most medical therapy, but for which a potentially useful therapeutic alternative is inhibition of angiogenesis. PATIENTS AND METHODS VEGF, VEGF-R1 and -R2 mRNA levels were analysed using the quantitative reverse transcription-polymerase chain reaction. RNA was extracted from 84 conventional (clear cell) RCCs (cRCC), 20 papillary (pRCC), six chromophobe (chRCC), and 27 corresponding kidney cortex tissues, obtained from 110 patients in whom high-quality RNA was available from the tumours (53 women and 57 men, mean age 64.7 years, range 25,85). RESULTS The VEGF, VEGF-R1, and -R2 mRNA levels were higher in tumour than in kidney cortex tissues. Among the RCC types, cRCC had higher VEGF levels than pRCC. In cRCC, VEGF-R2 levels were higher in stage I,II than in more advanced stages. In pRCC, VEGF and VEGF-R2 levels were higher in stage III than in stage I,II tumours. In cRCC, patients with VEGF levels below the median had a significantly shorter survival time than those with higher levels. By contrast, in pRCC, VEGF, VEGF-R1 and -R2 RNA levels above the median were related to adverse survival. Using multivariate analysis in cRCCs, VEGF-R1 mRNA level was the last factor to be omitted after stepwise elimination analysis. CONCLUSION VEGF and its receptors were associated with tumour stage and survival, but were not independent prognostic factors. Different RCC types had different expression patterns of VEGF and receptor mRNA levels. We conclude that different pathways might be involved in regulating angiogenesis in the specific RCC types. Detailed knowledge of angiogenesis in RCC is essential when designing new treatment trials where angiogenesis inhibition is used. [source]


    Transglutaminase 1-deficient recessive lamellar ichthyosis associated with a LINE-1 insertion in Jack Russell terrier dogs

    BRITISH JOURNAL OF DERMATOLOGY, Issue 2 2009
    K.M. Credille
    Summary Background, Congenital, nonepidermolytic cornification disorders phenotypically resembling human autosomal recessive ichthyosis have been described in purebred dog breeds, including Jack Russell terrier (JRT) dogs. One cause of gene mutation important to humans and dogs is transposon insertions. Objectives, To describe an autosomal recessive, severe nonepidermolytic ichthyosis resembling lamellar ichthyosis (LI) in JRT dogs due to insertion of a long interspersed nucleotide element (LINE-1) in the transglutaminase 1 (TGM1) gene. Methods, Dogs were evaluated clinically, and skin samples were examined by light and electron microscopy. Phenotypic information and genotyping with a canine microsatellite marker suggested TGM1 to be a candidate gene. Genomic DNA samples and cDNA generated from epidermal RNA were examined. Consequences of the mutation were evaluated by Western blotting, quantitative reverse transcription-polymerase chain reaction (RT-PCR) and enzyme activity from cultured keratinocytes. Results, Affected dogs had generalized severe hyperkeratosis. Histological examination defined laminated to compact hyperkeratosis without epidermolysis; ultrastructurally, cornified envelopes were thin. Affected dogs were homozygous for a 1980-bp insertion within intron 9 of TGM1. The sequence of the insertion was that of a canine LINE-1 element. Quantitative RT-PCR indicated a significant decrease in TGM1 mRNA in affected dogs compared with wild-type. TGM1 protein was markedly decreased on immunoblotting, and membrane-associated enzyme activity was diminished in affected dogs. Conclusions, Based on morphological and molecular features, this disease is homologous with TGM1-deficient LI in humans, clinically models LI better than the genetically modified mouse and represents its first spontaneous animal model. This is the first reported form of LI due to transposon insertion. [source]


    Reduced expression of nicotinic , subunits 3, 7, 9 and 10 in lesional and nonlesional atopic dermatitis skin but enhanced expression of , subunits 3 and 5 in mast cells

    BRITISH JOURNAL OF DERMATOLOGY, Issue 4 2008
    F. Kindt
    Summary Background, The skin cholinergic signalling system is modulated in atopic dermatitis (AD). Objectives, To investigate of the role of nicotinic acetylcholine receptors (nAChRs) in the pathogenesis of AD. Methods, We investigated the expression and localization of nAChR , subunits in AD by quantitative reverse transcription-polymerase chain reaction and immunohistochemistry of biopsies from lesional and nonlesional areas of AD skin and of skin biopsies from healthy control persons. Results, Our data demonstrate the presence of mRNA and protein of the nAChR , subunits 3, 5, 7, 9 and 10 in keratinocytes and mast cells in healthy and AD skin. Expression of the , subunits 3, 7, 9 and 10 was generally reduced in the skin of patients with AD whereas mast cells in AD but not in healthy skin showed ,3 and ,5 subunit immunoreactivity. Differences in the subunit mRNA levels between lesional and nonlesional skin were obtained for the , subunits 3, 9 and 10 with higher levels of ,3 but lower levels of ,10 subunit mRNA in lesional areas. No differences in the expression of the , subunits was found between the groups of extrinsic, intrinsic or mixed AD types, between genders and between smokers and nonsmokers. Conclusions, This supports the idea that the cholinergic system is dysregulated independently from inflammation in AD and that inflammation further modulates individual nAChR subunits. [source]


    Psoriasis genomics: analysis of proinflammatory (type 1) gene expression in large plaque (Western) and small plaque (Asian) psoriasis vulgaris

    BRITISH JOURNAL OF DERMATOLOGY, Issue 4 2004
    W. Lew
    Summary Background, Type 1 T cells are hypothesized to be central in the immunopathogenesis of psoriasis. Through elaboration of interferon (IFN)-,, type 1 T cells regulate the expression of many ,downstream' inflammatory genes, including an array of chemokines that regulate leucocyte trafficking and activation in skin lesions. Accordingly, disease progression and/or severity might be controlled by the degree to which differing cytokines and chemokines are overexpressed in focal skin regions. To examine this possibility, we studied two forms of chronic psoriasis vulgaris that differ significantly in overall severity and progression: small plaque (SP) psoriasis occurring in Korean patients, and large plaque (LP) psoriasis occurring in North American patients. Objectives, To characterize LP and SP psoriasis vulgaris with respect to expression of proinflammatory genes that define the type 1 T-cell axis in skin lesions [genes encoding interleukin (IL)-12, IFN-,, and IFN-,-regulated chemokines or inflammatory mediators]. Methods, Total cellular RNA of skin samples from groups of patients with LP or SP psoriasis was analysed by quantitative reverse transcription-polymerase chain reaction (TaqMan analysis) to compare the differences in mRNA expression of genes related to the IFN-, pathway. Results, The mRNA expression of keratin 16, CD25, IFN-,, IL-12 p40, signal transducer and activator of transcription-1, inducible nitric oxide synthase, IL-8, macrophage inflammatory protein-3,, monocyte chemoattractant protein-1, S100A12, IFN-,-inducible protein of 10 kDa, IFN-inducible T-cell ,-chemoattractant and monokine induced by IFN-, was increased in the lesions of both LP psoriasis and SP psoriasis. However, IL-18 mRNA expression was significantly different in the lesions of LP psoriasis in comparison with those of SP psoriasis. Conclusions, The results indicate that proinflammatory type 1 genes regulated by IFN-, are similarly increased in both SP and LP psoriasis, but a potential difference in IL-18 exists between these disease forms. The consistent activation of this set of genes argues for a central role of IFN-, as a molecular regulator of inflammation in these distinct subtypes of psoriasis vulgaris. In contrast, disease extent/severity must be controlled by yet other factors. [source]


    Identification of transcripts modulated by ETV6 expression

    BRITISH JOURNAL OF HAEMATOLOGY, Issue 1 2007
    Gino Boily
    Summary Deletions at chromosome 12p12-13 are observed in 26,47% of childhood pre-B acute lymphoblastic leukaemia (ALL) cases, suggesting the presence of a tumour suppressor gene (TSG). Accumulating genetic and functional evidence points to ETV6 as being the most probable TSG targeted by the deletions. ETV6 is a ubiquitously expressed transcription factor of the ETS family with very few known targets. To understand its function and to elucidate the impact of its absence in leukaemia, we conducted a study to identify targeted genes. Following the induction of ETV6 expression, global expression was evaluated at different time points. We identified 87 modulated genes, of which 10 (AKR1C1, AKR1C3, IL18, LUM, PHLDA1, PTGER4, PTGS2, SPHK1, TP53 and VEGF) were validated by real-time quantitative reverse transcription-polymerase chain reaction. To assess the significance of the validated candidate genes in leukaemia, their expression patterns were determined, as well as that of ETV6, in pre-B ALL patients. The expression of IL18, LUM, PTGER4, SPHK1 and TP53 was significantly correlated with that of ETV6, further suggesting that ETV6 could regulate the expression of these genes in leukaemia. This work constitutes another step towards the understanding of the functions of ETV6 and the impact of its inactivation in childhood leukaemia. [source]


    Hexosaminidase-altered Aberrant Crypts, Carrying Decreased Hexosaminidase , and , Subunit mRNAs, in Colon of 1,2-Dimethylhydrazine-treated Rats

    CANCER SCIENCE, Issue 2 2001
    Tetsuya Tsukamoto
    Aberrant crypt foci (ACF), consisting of morphologically irregular crypts, are thought to be precancerous lesions for colon cancers. For their molecular analysis, it is necessary to avoid contamination with adjacent normal crypts and stromal cells. Decreased hexosaminidase activity in ACF, which has been histochemically demonstrated, was used in the present study to classify isolated crypts in combination with morphological changes. The length, rim diameter, and width (average±SD, ,m) of hexosaminidase-positive (Hex+) crypts were 238.6±40.4, 89.5±22.9, and 57.6±14.0, respectively. For hexosaminidase-negative (Hex-) crypts, the values were 314.4±77.8, 140.3±45.7, and 97.3±34.7, the width being 1.69 tunes greater (P<0.0001). Crypts wider than 115 ,m (approximately 2 tunes the average size of Hex+ crypts) were all from ACF, judging from hexosaminidase staining. To analyze transcription levels of Hex , and , subunits (Hexa and Hexb, respectively), real-tune relative quantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis was performed using the LightCycler system. In aberrant crypts, both Hexa and Hexb were significantly down-regulated to 0.266 (P<0.002) and 0.131 (P<0.001) units, respectively, compared with those in morphologically normal crypts, with , -actin as the internal standard. This decrease could be a molecular marker for precancerous enzyme-altered ACF. [source]


    Expression of Drug Resistance-related Genes in Head and Neck Squamous Cell Carcinoma and Normal Mucosa

    CANCER SCIENCE, Issue 1 2000
    Shitau Hirata
    We examined the expression levels of mRNA for multidrug resistance 1 (MDR1), multidrug resistance-associated protein (MRP), human canalicular multispecific organic anion transporter (cMOAT), lung resistance-related protein (LRP), topoisomerase II,, ,(Topo II,, ,) and topoisomerase I (Topo I) genes in human head and neck squamous cell carcinoma (HNSCC) specimens and mucosa (HNM) specimens, to elucidate their roles in relation to the biological characteristics and drug resistance in vivo. Fifty-eight samples (45 head and neck carcinomas and 13 head and neck mucosa) obtained during surgical resection or biopsy from 38 patients were analyzed using the quantitative reverse transcription-polymerase chain reaction (RT-PCR) method. MDR1, MRP, LRP, Topo II,, Topo II,, and Topo I gene transcripts were detected in all the samples tested, but cMOAT mRNA was not detected in them. Comparisons of the expression levels in HNSCC with those in HNM showed that the Topo II, gene expression level was higher in HNSCC than in HNM (P=0.0298). Moreover, the Topo II, mRNA level was significantly higher in metastatic lymph node samples of HNSCC than in HNM samples (P=0.0205). There were no significant differences in the six genes' expression levels between samples exposed to platinum drugs and those not exposed to platinum drugs. These results suggest that it may be effective in anticancer therapy to use topoisomerase-targetting drugs against HNSCC, especially metastatic neck tumors, and that the expression of these genes in HNSCC is not associated with platinum drug exposure. [source]