European Society of Human Genetics Congress, Nice, France, 16 - 19 June 2007, vol.1, no.1, pp.154
Cancer occurs as a result of various genetic and epigenetic mechanisms
which cause loss/gain of functions of tumour suppressor genes,
oncogenes, DNA repair and apoptosis genes. DAP kinase gene, which
is an proapoptotic gene, induces the cell to apoptosis response to several
internal and external apoptotic stimulants. Changes occurring in
DAP kinase gene cause uncontrolled proliferation instead of going to
apoptosis of the cell and cause development. Therefore DAP Kinase
gene is described as a tumor suppressor gene. DNA methylation, one
of epigenetic mechanisms that have as much importance as genetic
mechanisms in cancer formation can prevent gene expression by silencing.
Silencing of DAP kinase through this methylation mechanism
can be observed in many solid tumour and hematopoietic malignancies.
In this study methylation of DNAs of 35 patients with chronic myeloid
leukaemia and DNAs of 25 healthy patients were analysed by
Methylation Spesific PCR (MSP). As a result, it has been determined
that 4 of 12 CML patients with drug resistance have hypermethylation
and statistically the significant difference is established. However all of
the CML patients with no drug resistance and all of the control sample
groups DNAs don’t have methylation. In this study although no correlation
is found between hypermethylation of DAPK1 which is defined as
a tumour suppressor gene and formation of CML, significant relation
between hypermethylation of DAPK1and progress of CML and drug
resistance is determined.