간세포암종에서 TPEF의 Methylation에 의한 불활성화 = Inactivation of TPEF Gene by Aberrant Methylation inHepatocellular Carcinoma

다국어 초록 (Multilingual Abstract)

Background : Abnormalities of genomic methylation patterns have been shown to play a role
in the development of carcinoma, and the silencing of tumor suppressor genes is related to
local de novo methylation. Methods : Using methylation specific arbitrarily primed-Polymerase
Chain Reaction (Ms AP-PCR), we identified a 322 bp sequence that contained a 5’ un-translated
and exon1 regions of the TPEF gene. To evaluate the inactivation of the TPEF gene
through hypermethylation in hepatocellular carcinoma (HCC), we investigated the correlation
between methylation patterns and TPEF expression in tumor tissues of human HCC and cell
lines via a Combined Bisulfite Restriction Assay (CoBRA) and RT-PCR. Results : A dense
methylation pattern of the TPEF was detected in most cell lines, as well as in 10 of the 14
(71.4%) HCC tissues. In addition, loss of heterozygosity (LOH) from the TPEF gene was
observed in 5 of the 14 (36%) HCC tissues. Furthermore, RT-PCR analysis revealed TPEF
expression in 5 of 8 (62.5%) cell lines. Finally, treatment with a demethylating agent, 5-Aza-
2’-deoxycitidine (5-AzaC), increased the expression of TPEF mRNA. Conclusion : These
results indicate that inactivation of the TPEF gene through hypermethylation may be a mechanism
by which tumorigenesis occurs in HCC.

참고문헌 (Reference)

1 Wong N, "tocellular carcinoma by spectral karyotyping" 32 : 1060-1068, 2000

2 Singer-Sam J, "X chromosome inactivation and DNA methylation" 64 : 358-384, 1993

3 Barlow DP, "The mouse insulin-like growth factor type-2 receptor is imprinted and closely linked to the Tme locus" 349 : 84-87, 1991

4 Liang G, "The gene for a novel transmembrane protein containing epidermal growth 14 정운복∙김순영∙전소영 외 6인 factor and follistatin domains is frequently hypermethylated in human tumor cells" 60 : 4907-4912, 2000

5 Kanai Y, "The E-cadherin gene is silenced by CpG methylation in human hepatocellular carcinomas" 71 : 355-359, 1997

6 Glynne-Jones E, "TENB2, a proteoglycan identified in prostate cancer that is associated with disease progression and androgen independence" 94 : 178-184, 2001

7 Herman JG, "Silencing of the VHL tumor-suppressor gene by DNA methylation in renal carcinoma" 91 : 9700-9704, 1994

8 Yoshiura K, "Silencing of the E-cadherin invasion-suppressor gene by CpG methylation in human carcinomas" 92 : 7416-7419, 1995

9 Endo C, "Sequential loss of heterozygosity in the progression of squamous cell carcinoma of the lung" 78 : 612-615, 1998

10 Sambrook J, "Molecular Cloning: A laboratory manual. 3rd" Cold Spring Harbor 6.1-6.11, 2001

11 Herman JG, "Methylation- specific PCR: a novel PCR assay for methylation status of CpG islands" 93 : 9821-9826, 1996

12 Ottaviano YL, "Methylation of the estrogen receptor gene CpG island marks loss of estrogen receptor expression in human breast cancer cells" 54 : 2552-2555, 1994

13 Ransom DT, "Loss of heterozygosity on chromosome 2q: possibly a poor prognostic factor in head and neck cancer" 20 : 404-410, 1998

14 Shiraishi M, "Isolation of DNA fragments associated with methylated CpG islands in human adenocarcinomas of the lung using a methylated DNA binding column and denaturing gradient gel electrophoresis" 96 : 2913-2918, 1999

15 Peinado MA, "Isolation and characterization of allelic losses and gains in colorectal tumors by arbitrarily primed polymerase chain reaction" 89 : 10065-10069, 1992

16 Schmutte C, "Involvement of DNA methylation in human carcinogenesis" 379 : 377-388, 1998

17 Liew CT, "High frequency of p16INK4A gene alterations in hepatocellular carcinoma" 18 : 789-795, 1999

18 Young J, "HPP1: a transmembrane protein- encoding gene commonly methylated in colorectal polyps and cancers" 98 : 265-270, 2001

19 Welsh J, "Fingerprinting genomes using PCR with arbitrary primers" 18 : 7213-7218, 1990

20 Lee WH, "Cytidine methylation of regulatory sequences near the pi-class glutathione S-transferase gene accompanies human prostatic carcinogenesis" 91 : 11733-11737, 1994

21 Bird AP, "CpG-rich islands and the function of DNA methylation" 321 : 209-213, 1986

22 Moiseeva EP, "Characterisation of the promoter which regulates expression of a phosphoglucomutase-related protein, a component of the dystrophin/utrophin cytoskeleton predominantly expressed in smooth muscle" 248 : 634-643, 1997