Detection of gene promoter methylation and mRNA, protein expression levels of E-cadherin in nasopharyngeal carcinoma / 中华病理学杂志
Chinese Journal of Pathology
; (12): 25-30, 2003.
Article
in Zh
| WPRIM
| ID: wpr-255362
Responsible library:
WPRO
ABSTRACT
<p><b>OBJECTIVE</b>To detect the gene promoter methylation, mRNA and protein expression levels of E-cadherin and beta-catenin in primary and metastatic tumor samples of nasopharyngeal carcinoma (NPC), and to investigate the mechanism of invasion and metastasis of neoplastic cell in NPC.</p><p><b>METHODS</b>Twenty-one patients with NPC were studied. The samples of primary tumor and paired lymph node metastatic tumor were collected and examined for aberrant gene promoter methylation in E-cadherin by DNA Methylation-specific polymerase chain reaction (MSP). Reverse transcriptase polymerase chain reaction (RT-PCR), Western blotting and immunohistochemical staining were adopted to detect mRNA and protein levels of E-cadherin and beta-catenin.</p><p><b>RESULTS</b>(1) The gene promoter methylation in E-cadherin was 52.4% (11/21) in primary tumor of NPC, and 80.9% (17/21) in lymph node metastatic tumor, which existed significant difference (P < 0.05). (2) In primary tumor, about 80% (0 approximately 100%) neoplastic cells expressed E-cadherin protein on the average, which was significantly higher than that of metastatic tumor (50% on the average, P = 0.004). The expression levels of beta-catenin protein were high in both primary and metastatic tumors, but with no statistic difference (P = 0.698). (3) By Western blotting analysis, the relative intensity of protein expression in E-cadherin was significantly higher in primary tumor (206.7 +/- 32.7) compared to that of metastatic tumor (65.0 +/- 15.9), while the expression of beta-catenin protein showed no difference between them (P = 0.754). (4) mRNA expression level of E-cadherin was higher in primary tumor than that of metastatic tumor.No remarkable difference was found for the mRNA expression of beta-catenin.</p><p><b>CONCLUSIONS</b>(1) Downregulation of mRNA and protein expression of E-cadherin may play a critical role in neoplastic cell invasion and metastasis in NPC. The aberrant promoter methylation of E-cadherin may ultimately alter the mobility and scattering of tumor cells in NPC. (2) Downregulation of E-cadherin alone may be enough for the tumor cell to lose intercellular adhesions which results in tumor cell invasion and metastasis. However, mutant beta-catenin could also involve in this progress. (3) The detection of gene promoter hypermethylation of E-cadherin should be evaluated in the screening and surveillance of NPC.</p>
Full text:
1
Index:
WPRIM
Main subject:
Pathology
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RNA, Messenger
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Cadherins
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Down-Regulation
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Trans-Activators
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Nasopharyngeal Neoplasms
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Promoter Regions, Genetic
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DNA Methylation
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Cytoskeletal Proteins
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Beta Catenin
Type of study:
Diagnostic_studies
Limits:
Adult
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Aged
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Female
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Humans
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Male
Language:
Zh
Journal:
Chinese Journal of Pathology
Year:
2003
Type:
Article