Open AccessComparison of telomere length and insulin‐like growth factor‐binding protein 7 promoter methylation between breast cancer tissues and adjacent normal tissues in Turkish women
Author(s) -
Kaya Zehra,
Akkiprik Mustafa,
Karabulut Sevgi,
Peker Irem,
Gullu Amuran Gokce,
Ozmen Tolga,
Gulluoglu Bahadır M.,
Kaya Handan,
Ozer Ayse
Publication year - 2017
Publication title -
journal of clinical laboratory analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.536
H-Index - 50
eISSN - 1098-2825
pISSN - 0887-8013
DOI - 10.1002/jcla.22083
Subject(s) - methylation , telomere , dna methylation , breast cancer , biology , cancer , insulin like growth factor binding protein , insulin like growth factor , growth factor , cancer research , gene expression , gene , genetics , receptor
Background Both insulin‐like growth factor‐binding protein 7 ( IGFBP 7) and telomere length ( TL ) are associated with proliferation and senescence of human breast cancer. This study assessed the clinical significance of both TL and IGFBP 7 methylation status in breast cancer tissues compared with adjacent normal tissues. We also investigated whether IGFBP 7 methylation status could be affecting TL . Methods Telomere length was measured by quantitative PCR to compare tumors with their adjacent normal tissues. The IGFBP 7 promoter methylation status was evaluated by methylation‐specific PCR and its expression levels were determined by western blotting. Results Telomeres were shorter in tumor tissues compared to controls ( P <.0001). The mean TL was higher in breast cancer with invasive ductal carcinoma ( IDC ; n=72; P =.014) compared with other histological type (n=29), and TL in IDC with HER 2 negative (n=53; P =.017) was higher than TL in IDC with HER 2 positive (n=19). However, telomeres were shortened in advanced stages and growing tumors. IGFBP 7 methylation was observed in 90% of tumor tissues and 59% of controls ( P =.0002). Its frequency was significantly higher in IDC compared with invasive mixed carcinoma ( IMC ; P =.002) and it was not correlated either with protein expression or the other clinicopathological parameters. Conclusion These results suggest that IGFBP 7 promoter methylation and shorter TL in tumor compared with adjacent tissues may be predictive biomarkers for breast cancer. Telomere maintenance may be indicative of IDC and IDC with HER 2 (−) of breast cancer. Further studies with larger number of cases are necessary to verify this association.