METHYLATED APC AND GSTP1 GENES IN SERUM DNA CORRELATE WITH THE PRESENCE OF CIRCULATING BLOOD TUMOR CELLS AND ARE ASSOCIATED WITH A MORE AGGRESSIVE AND ADVANCED BREAST CANCER DISEASE

Christiane Matuschek, E. Bolke*, G. Lammering, P. A. Gerber, M. Peiper, Wilfried Budach, H. Taskin, H. B. Prisack, Gisela Schieren, K. Orth, H. Bojar

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

Background. Tumor-related methylated DNA and circulating tumor cells (CTC) m the peripheral blood might be of prognostic importance in breast cancer Thus, the aim of our study was to examine free methylated DNA and CTC in the blood from breast cancer patients and to correlate it with chnicopathological features known to influence prognosisMaterials and Methods. We prospectively obtained serum samples from 85 patients with breast cancer and 22 healthy volunteers. Sera were analysed by methylation specific PCR (MethyLight PCR) for five genes adenomatous polyposis coli (APC), ras association domain family protein 1A (RASSF1A), estrogen receptor 1 (ESR1), CDKN2A (p16) and glutathione s-transferase pt 1 (GSTP 1), Beta actin (ACTB) served as control. In parallel matched peripheral blood of 63 patients was used to assay for circulating tumor cells in the peripheral blood by a modified immunomagnetic AdnaTest BreastCancerSelect with PCR detection for EPCAM, MUC1, MGB1 and SPDEF.Results. A hypermethylation in the APC gene in 29% (25/85), in RASSF1A in 26% (22/85), in GSTP I in 18% (14/76) and in ESR1 in 38% (32/85) of all breast cancer patients was detected. No hypermethylation of CDKN2A was found (0/25). Blood samples of patients were defined CTC positive by detecting the EPCAM 13% (8/63), MUC1 16% (10/63), MGB 9% (5/55), SPDEF 12% (7/58) and in 27% detecting one or more genes (15/55). A significant difference was seen in methylated ARC DNA between cancer patients and healthy volunteers Moreover, methylated A PC, RASSF1 and CTC were significantly different in metastatic versus non-metastatic disease. In addition, the presence of methylated ARC. RASSF1A and CTC correlated significantly with AJCC-staging (p = 0.001, p = 0 031 and 0.002, respectively) High incidences of methylations were found for the genes RASSF1 and ESR1 in healthy individuals (both 23% 5/22). Methylated GSTP1 was predominantly found in the serum of patients with large primaries (p 0 023) and was highly significantly correlated with positive Her2/neu status (p = 0.003). Elevated scrum CA15.3 was strongly correlated with methylated ARC and CTC detection (both p = 0.000). Methylated ESR1 failed to exhibit significant correlations with any of the above mentioned parameters. The presence of CTC in peripheral blood was significantly associated with methylated ARC (p = 0 012) and methylated GSTP1 (p = 0.001).Conclusion: The detection of methylated APC and GSTP1 DNA in serum correlated with the presence of CTC in the blood of breast cancer patients Both methylated DNA and CTC correlated with a more aggressive tumor biology and advanced disease.
Original languageEnglish
Pages (from-to)277-286
JournalEuropean Journal of Medical Research
Volume15
Issue number7
DOIs
Publication statusPublished - 26 Jul 2010

Keywords

  • methylated genes
  • circulating tumor cells
  • circulating DNA
  • breast cancer

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