Virchows Archiv

, 455:469

Borderline and malignant phyllodes tumors display similar promoter methylation profiles

Authors

  • Jo-Heon Kim
    • Department of PathologyChonnam National University Medical School and Research Institute of Medical Sciences
  • Yoo Duk Choi
    • Department of PathologyChonnam National University Medical School and Research Institute of Medical Sciences
    • Department of PathologyChonnam National University Medical School and Research Institute of Medical Sciences
    • Department of PathologyChonnam National University Hwasun Hospital
  • Jae Hyuk Lee
    • Department of PathologyChonnam National University Medical School and Research Institute of Medical Sciences
  • Jong Hee Nam
    • Department of PathologyChonnam National University Medical School and Research Institute of Medical Sciences
  • Chan Choi
    • Department of PathologyChonnam National University Medical School and Research Institute of Medical Sciences
  • Min Ho Park
    • Department of SurgeryChonnam National University Medical School and Research Institute of Medical Sciences
  • Jung Han Yoon
    • Department of SurgeryChonnam National University Medical School and Research Institute of Medical Sciences
Original Article

DOI: 10.1007/s00428-009-0858-z

Cite this article as:
Kim, J., Choi, Y.D., Lee, J.S. et al. Virchows Arch (2009) 455: 469. doi:10.1007/s00428-009-0858-z

Abstract

Mammary phyllodes tumors (PTs) are uncommon fibroepithelial neoplasms. On the basis of histologic criteria, PTs can be divided into benign, borderline, and malignant groups; however, the histologic distinction of PTs is often difficult and arbitrary. In breast cancer, promoter hypermethylation is a common phenomenon, but there are no data available concerning methylation status in PTs. The aim of this study was to assess whether the methylation profiles support the classification of PTs into three subgroups. A multiplex, nested, methylation-specific polymerase chain reaction approach was used to examine promoter methylation of five genes (GSTP1, HIN-1, RAR-β, RASSF1A, and Twist) in 87 PTs (54 benign, 23 borderline, and 10 malignant). Immunohistochemical staining for GSTP1 was performed using tissue microarray blocks to determine whether GSTP1 promoter hypermethylation correlated with loss of GSTP1 expression. There was a trend of increasing methylation frequency with increasing grade of PTs. The methylation frequency of all genes and the mean number of methylated genes in borderline and malignant PTs were higher than those in benign PTs; however, there were no statistically significant differences between borderline and malignant PTs. GSTP1 promoter hypermethylation was associated with loss of GSTP1 expression (p < 0.001). These results suggest that PTs segregate into only two groups on the basis of their methylation profiles: the benign group and the combined borderline/malignant group.

Keywords

Breast tumorPhyllodesClassificationMethylation

Copyright information

© Springer-Verlag 2009