J Korean Med Sci.  2009 Feb;24(1):97-103. 10.3346/jkms.2009.24.1.97.

EMP3 Overexpression in Primary Breast Carcinomas is not Associated with Epigenetic Aberrations

• Zhou W
• Jiang Z
• Li X
• Xu F
• Liu Y
• Wen P
• Kong L
• Hou M
• Yu J

• KMID: 1794413
• DOI: http://doi.org/10.3346/jkms.2009.24.1.97

Abstract

Epithelial membrane protein 3 (EMP3) is a trans-membrane signaling molecule with important roles in the regulation of apoptosis, differentiation and invasion of cancer cells, but the detailed is largely still unknown. We analyzed the mRNA levels and methylation statuses of EMP3 in 63 primary breast carcinomas and assessed their correlations with clinicopathologic variables. The expression of EMP3 mRNA in primary breast carcinomas was significantly higher than the expression of 20 normal breast tissues (p<10(-7)). EMP3 overexpression in breast carcinomas was significantly related to histological grade III (p=3.9X10(-7)), lymph node metastasis (p= 0.003), and strong Her-2 expression (p=3.3X10(-6)). Hypermethylation frequencies of EMP3 were detected in 36.5% of breast carcinomas by methylation-specific polymerase chain reaction. However, no significant correlations were found between methylation status of EMP3 and mRNA expression levels as well as other clinical parameters. In conclusion, EMP3 may be a novel marker of tumor aggressiveness. Overexpression of EMP3 in primary breast carcinoma is not associated with DNA methylation.

Keyword

PMP22/EMP/MP20 Gene Family; Metastasis; Breast Neoplasms; DNA Methylation; Epigenetics, Genetic

MeSH Terms

Adult
Breast Neoplasms/*genetics/pathology
Carcinoma/*genetics/pathology
DNA Methylation
Epigenesis, Genetic
Female
Gene Expression Regulation, Neoplastic
Humans
Lymphatic Metastasis
Membrane Glycoproteins/*genetics/metabolism
Middle Aged
Neoplasm Staging
RNA, Messenger/metabolism
Receptor, erbB-2/genetics/metabolism
Severity of Illness Index

Figure

• 

  Fig. 1 Expression and methylation analyses of EMP3 in primary breast carcinomas. (A) Semi-quantitative RT-PCR analysis showing EMP3 mRNA is over-expressed in primary breast carcinoma (TB) as compared with their corresponding nonmalignant tissues (NB). (B) Methylation analysis of EMP3 in primary breast carcinomas (TB) by methylation-specific PCR. Lane U, unmethylated; Lane M, methylated. Data in (A, B) are representative of two independent experiments.

• 

  Fig. 2 EMP3 mRNA levels were assayed by real-time PCR and compared between tumors with hypermethylation (M) and without hypermethylation (UM).

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