Correlation between the DNA methylation and gene expression of IGFBP5 in breast cancer.
BACKGROUND
The insulin-like growth factor binding protein5 (IGFBP5) is often dysregulated in human cancers and considered neither a tumor suppressor nor an oncogene.


OBJECTIVE
We aim to examine the reason of the changeable gene regulation of IGFBP5 in the case of methylation in breast cancer.


METHODS
We used methyl-specific polymerase (MSP) chain reaction to detect CpG methylation of IGFBP5 promoter and exon-I in breast cancer and adjacent tissues. Gene expression is evaluated by quantative polymerase chain reaction (qPCR).


RESULTS
IGFBP5 methylation was detected in 24 of 58 (41%) and 54 of 56 (96.5%) promoter and exon-I site respectively in tumor tissues. In adjacent tissues 17 of 58 (29%) and 53 of 56 (96.5%) was methylated. IGFBP5 expression was higher estrogene receptor (ER)(+) than ER(-) patients (p = 0.0549). Beside, we found a positive correlation between the expression of IGFBP5 and G2 tumor grade (p = 0.0131). However, no correlation was observed between IGFBP5 expression and age, menopause or the presence of lymph node metastasis (p > 0.05).


CONCLUSIONS
In summary, our results showed that IGFBP5 promoter and exon-I methylation did not have any differences between tumor and adjacent tissues so that IGFBP5 methylation did not change IGFBP5 gene regulation in breast cancer. This is the first study investigating the IGFBP5 gene methylation in breast cancer.
Marmara University, School of Medicine, Medical Biology Department, Istanbul, Turkey.|Bayburt University, Health Services Vocational School, Bayburt, Turkey.
Sevgi
S
Karabulut
Marmara University, School of Medicine, Medical Biology Department, Istanbul, Turkey.|Yüzüncü Yıl University, School of Medicine, Medical Biology Department, Van, Turkey.
Zehra
Z
Kaya
Marmara University, School of Medicine, Medical Biology Department, Istanbul, Turkey.
Gökçe Gūllū
GG
Amuran
Marmara University, School of Medicine, Medical Biology Department, Istanbul, Turkey.
Irem
I
Peker
Marmara University, School of Medicine, General Surgery Department, Istanbul, Turkey.
Tolga
T
Özmen
Marmara University, School of Medicine, General Surgery Department, Istanbul, Turkey.
Bahadır M
BM
Gūllūoḡlu
Marmara University, School of Medicine, Pathology Department, Istanbul, Turkey.
Handan
H
Kaya
Marmara University, School of Medicine, Medical Biology Department, Istanbul, Turkey.
Can
C
Erzik
Marmara University, School of Medicine, Medical Biology Department, Istanbul, Turkey.
Ayşe
A
Ōzer
Marmara University, School of Medicine, Medical Biology Department, Istanbul, Turkey.
Mustafa
M
Akkiprik
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D018899:CpG Islands; D019175:DNA Methylation; D005091:Exons; D005260:Female; D015870:Gene Expression; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D018975:Insulin-Like Growth Factor Binding Protein 5 / Q000235:genetics*; D008875:Middle Aged; D060787:Neoplasm Grading; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000378:metabolism*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism
D018975:Insulin-Like Growth Factor Binding Protein 5; D012333:RNA, Messenger; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human
IGFBP5; MSP; breast cancer; methylation; promoter