Biological Research (Jan 2015)

Colorectal cancer DNA methylation patterns from patients in Manaus, Brazil

  • Fabiana Greyce Oliveira Almeida,
  • Priscila Ferreira de Aquino,
  • Afonso Duarte Leäo de Souza,
  • Antonia Queiroz Lima de Souza,
  • Sonia do Carmo Vinhote,
  • Thais Messias Mac-Cormick,
  • Marcelo Soares da Mota Silva,
  • Sidney Raimundo Silva Chalub,
  • Juliana de Saldanha da Gama Fischer,
  • Paulo Costa Carvalho,
  • Maria da Gloria da Costa Carvalho

DOI
https://doi.org/10.1186/S40659-015-0042-7
Journal volume & issue
Vol. 48, no. 0
pp. 1 – 6

Abstract

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BACKGROUND: DNA methylation is commonly linked with the silencing of the gene expression for many tumor suppressor genes. As such, determining DNA methylation patterns should aid, in times to come, in the diagnosis and personal treatment for various types of cancers. Here, we analyzed the methylation pattern from five colorectal cancer patients from the Amazon state in Brazil for four tumor suppressor genes, viz.: DAPK, CDH1, CDKN2A, and TIMP2 by employing a polymerase chain reaction (PCR) specific to methylation. Efforts in the study of colorectal cancer are fundamental as it is the third most of highest incidence in the world. RESULTS: Tumor biopsies were methylated in 1/5 (20 %), 2/5 (40 %), 4/5 (80 %), and 4/5 (80 %) for CDH1, CDKN2A, DAPK, and TIMP2 genes, respectively. The margin biopsies were methylated in 3/7 (43 %), 2/7 (28 %), 7/7 (100 %), and 6/7 (86 %) for CDH1, CDKN2A, DAPK, and TIMP2, respectively. CONCLUSIONS: Our findings showed DAPK and TIMP2 to be methylated in most samples from both tumor tissues and adjacent non-neoplastic margins; thus presenting distinct methylation patterns. This emphasizes the importance of better understanding of the relation of these patterns with cancer in the context of different populations.

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