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hTERT mRNA (htert + mrna)

Distribution by Scientific Domains
Medical Sciences100%

Terms modified by hTERT mRNA

  • htert mrna expression
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    Selected Abstracts

    ENDOSCOPIC TRANSPAPILLARY CATHETERIZATION INTO THE GALLBLADDER FOR DIAGNOSIS OF GALLBLADDER CARCINOMA

    DIGESTIVE ENDOSCOPY, Issue 2 2006
    Naohito Uchida
    It is often difficult to determine the precise nature of lesions in the gallbladder by radiographic, endoscopic and ultrasonographic methods. The approach to the gallbladder by a percutaneous transhepatic route has been reported. However, there is a possibility of seeding tumor cells into the peritoneal cavity and liver in a percutaneous procedure. On the contrary, transpapillary route can be performed without a possibility of seeding. The double-contrast cholecystography, intragallbladder sonography, direct biopsy of gallbladder lesions and cytology using gallbladder bile have been performed by the procedure of the transpapillary catheterization into the gallbladder. Confirming malignancy by histopathological diagnosis is desirous for determining therapeutic strategy in gallbladder carcinoma. Gathering gallbladder bile is comparatively easier than biopsy of the lesion using the transpapillary catheterization into the gallbladder. Examination of telomerase-related molecules is useful for diagnosis of pancreatic carcinoma. Usefulness of combination assay of human telomerase reverse transcriptase mRNA (hTERT mRNA) and cytology using gallbladder bile obtained by transpapillary catheterization is reported here. However, it would appear that hTERT mRNA is less important in the diagnosis of gallbladder carcinoma than in that of pancreatic carcinoma. When the molecular biological substances with higher sensitivity are found, the reliance of the combination assay of the molecular biological substances and cytology will be established. [source]

    Human telomerase catalytic subunit gene re-expression is an early event in oral carcinogenesis

    HISTOPATHOLOGY, Issue 1 2004
    B Luzar
    Aims:, Detection of telomerase catalytic subunit (hTERT) mRNA has been used as a surrogate marker for estimation of telomerase activity. The exact role and timing of telomerase re-activation, a key enzyme implicated in cellular immortalization and transformation, in the multistep process of oral carcinogenesis is still unknown. The aim was to test the hypothesis that (i) quantitative rather than qualitative differences exist in the level of hTERT mRNA expression between normal oral mucosa, different grades of oral epithelial abnormalities and squamous cell carcinomas of the oral cavity, and that (ii) hTERT gene re-expression is an important, probably early event in oral carcinogenesis. Methods and results: The relative quantity of hTERT mRNA was analysed in 45 frozen oral epithelia representing different morphological stages of oral carcinogenesis classified according to the Ljubljana classification and in 37 oral squamous cell carcinomas, using a commercially available LightCycler Telo TAGGG hTERT Quantification kit. hTERT mRNA was not detected in normal or reactive hyperplastic oral epithelia, but was present in 43% of atypical hyperplasias (premalignant lesions), 60% of intraepithelial carcinomas and 68% of oral squamous cell carcinomas. Statistical analysis revealed two groups of oral epithelial changes, with significant differences in the levels of hTERT mRNA expression: 1, normal and reactive hyperplastic oral epithelium, and 2, atypical hyperplasia, intraepithelial carcinomas and squamous cell carcinomas. Conclusion:, These data suggest that hTERT gene re-expression represents an early event in the multistep process of oral carcinogenesis, already detectable at the stage of precancerous oral epithelial changes. Nevertheless, other genetic aberrations appear to be necessary for progression of oral epithelial abnormalities towards invasive squamous cell carcinoma. [source]

    Genistein induces cell growth inhibition in prostate cancer through the suppression of telomerase activity

    INTERNATIONAL JOURNAL OF UROLOGY, Issue 1 2005
    HIDEKI OUCHI
    Abstract Aim:, To clarify the mechanism of the anticancer effect of genistein, we examined the effect of genistein on telomerase activity in prostate cancer cells. We hypothesized that genistein may exert its anticancer effect by modifying telomerase activity in prostate cancer cells. Methods:, Prostate cancer (LNCaP) cells were cultured with genistein and the number of viable cells was counted. Growth medium was also collected to measure prostate-specific antigen (PSA) concentration. Polymerase chain reaction (PCR)-based telomeric repeat amplification protocol (TRAP) assay and reverse transcriptase (RT)-PCR analysis were performed to investigate telomerase activity and the expression of human telomerase reverse transcriptase (hTERT), c-myc and p21 mRNA. To examine the possibility that hTERT transcriptional activity is modulated by genistein, transient cell transfection studies were performed by using luciferase reporter assay. Telomere repeat amplification protocol (TRAP) assay and PCR analysis of hTERT were performed in androgen independent cells, DU-145. Results:, Cell growth of LNCaP was inhibited by genistein and PSA secretion was similarly reduced. In TRAP assay, the telomerase activity of LNCaP cells was reduced by genistein. Reverse transcriptase-PCR analysis revealed that the expression of hTERT and c-myc mRNA was down-regulated by genistein, whereas p21 mRNA increased in response to genistein. Luciferase reporter assay revealed that genistein reduced the transcriptional activity of hTERT. In DU-145 cells, telomerase activity and the expression of hTERT mRNA were also reduced by genistein. Conclusion:, The current study elucidated the molecular mechanism of cell growth inhibition by genistein. The antiproliferative effects of genistein seem to be exerted on the hTERT transcriptional activity via different molecular pathways. [source]

    Inhibition of human telomerase reverse transcriptase by nonsteroidal antiinflammatory drugs in colon carcinoma

    CANCER, Issue 6 2006
    Hua He M.Phil.
    Abstract BACKGROUND Telomerase activation, which is observed in most human cancers, plays an important role in carcinogenesis. Human telomerase reverse transcriptase (hTERT) is a subunit of telomerase that is essential for telomerase activity. The aim of the study was to investigate whether nonsteroidal antiinflammatory drugs (NSAIDs) inhibit telomerase activity and hTERT. METHODS Four colon carcinoma cell lines, HT-29, COLO205, CRL-2134, and SW1116, were used in the experiments. Polymerase chain reaction-based telomeric repeat amplification (TRAP) enzyme-linked immunosorbent assay (ELISA) was used to measure telomerase activity in the cells after treatment with aspirin, indomethacin, or SC-236 (a specific cyclooxygenase-2 [COX-2] inhibitor). Expression of hTERT mRNA and protein was detected by reverse transcription,polymerase chain reaction (RT-PCR) and Western blotting, respectively. The dual luciferase reporter assay was performed to identify the potential cis-response elements to NSAIDs in the promoter region of hTERT. RESULTS Aspirin, indomethacin, and SC-236 inhibited telomerase activity in HT-29, COLO205, and CRL-2134 cell lines, but not in the SW1116 cell line. NSAIDs inhibited hTERT mRNA and protein expression through suppression of hTERT transcriptional activity. The hTERT promoter fragment ,145 to ,330 basepairs (bp) upstream of the ATG starting site was sufficient to respond to the NSAID-induced inhibitory effect and the inhibition was COX-2-independent. CONCLUSION NSAIDs inhibit telomerase activity at hTERT transcriptional, mRNA, and protein levels in colon carcinoma cells. The hTERT promoter fragment ,145 to ,330 bp may be the cis-response element to NSAIDs. Cancer 2006. © 2006 American Cancer Society. [source]

    The diagnostic and prognostic relevance of human telomerase reverse transcriptase mRNA expression detected in situ in patients with nonsmall cell lung carcinoma

    CANCER, Issue 5 2003
    Yuka Fujita M.D.
    Abstract BACKGROUND The objectives of this study were to evaluate the diagnostic and prognostic relevance of human telomerase reverse transcriptase (hTERT) detected in situ in patients with nonsmall cell lung carcinoma (NSCLC) and to investigate the possible correlations between hTERT mRNA in NSCLC and the patients' clinicopathologic features, including survival. METHODS hTERT mRNA was detected by in situ hybridization in 146 samples from patients with NSCLC. The signal intensity of hTERT mRNA expression was evaluated by two independent observers. The expression level was defined subjectively as strong, moderate, or weak. RESULTS hTERT mRNA was detected mainly in the cytoplasm of tumor cells. It was detected in the cytoplasm of 100% of samples from patients with NSCLC but was not detected in normal lung tissue, except in activated lymphocytes. There was a significant correlation between hTERT mRNA expression and pathologic tumor status, pathologic disease stage (pStage), and Ki-67 labeling index. There was no significant correlation between hTERT mRNA expression and age, gender, pathologic lymph node status (pN), histology, or tumor differentiation. The 5-year survival rates for patients with strong and moderate hTERT mRNA expression levels were 46.9% and 77.9%, respectively; the difference was statistically significant (P = 0.0001). A multivariate analysis of survival using a stepwise procedure revealed that hTERT mRNA expression, pN status, pStage, and age were statistically significant prognostic factors (P = 0.0029, P = 0.0012, P = 0.0237, and P = 0.0496, respectively). CONCLUSIONS The findings suggested that hTERT mRNA expression may be useful for the diagnosis of NSCLC and also may be an independent prognostic factor for patients with NSCLC. Cancer 2003;98:1008,13. © 2003 American Cancer Society. DOI 10.1002/cncr.11611 [source]

    Quantitative analysis of hTERT mRNA levels in cells microdissected from cytological specimens

    CANCER SCIENCE, Issue 11 2008
    Hayato Fujita
    Clinicians frequently require cytopathological assessment of tumor samples for preoperative diagnosis, but in some specimens, diagnosis remains inconclusive after cytological examination. To date, several molecular markers, including human telomerase reverse transcriptase (hTERT), have been assessed for the ability to detect malignancy. However, analyses using whole cytological specimens are generally affected by contamination of untargeted cells. The present study investigated the feasibility of more sensitive examination by quantitative mRNA analysis of target cells microdissected from cytological specimens. Laser capture microdissection (LCM) was used to obtain target cells from cytological specimens. hTERT mRNA levels were then measured in target cells by quantitative real-time RT-PCR (qRT-PCR). The effect of RNA fragmentation on qRT-PCR was also assessed. Total RNA from cytological specimens was sometimes fragmented to a large degree. To avoid the effect of RNA fragmentation, gene specific priming and PCR primers generating short PCR products were used and no difference in delta Ct values between fragmented and non-fragmented RNA were found. hTERT mRNA levels were measured in cells microdissected from 33 cytological specimens. The levels of hTERT mRNA were significantly higher in malignant cases compared to those in non-malignant cases (P = 0.0003). The sensitivity was 96.2%, even when the specificities were 100%. High levels of hTERT mRNA were also found in three cases that were not diagnosed as malignant by cytological examination. Quantitative assessment of hTERT mRNA levels in cells microdissected from cytological specimens is a potential diagnostic tool to potentiate cytological examination in diagnosing malignancy. (Cancer Sci 2008; 99: 2244,2251) [source]