Overexpressed genes/ESTs and characterization of distinct amplicons on 17q23 in breast cancer cells

Erson Bensan, Ayşe Elif
17q23 is a frequent site of gene amplification in breast cancer. Several lines of evidence suggest the presence of multiple amplicons on 17q23. To characterize distinct amplicons on 17q23 and localize putative oncogenes, we screened genes and expressed sequence tags (ESTs) in existing physical and radiation hybrid maps for amplification and overexpression in breast cancer cell lines by semiquantitative duplex PCR, semiquantitative duplex RT-PCR, Southern blot, and Northern blot analyses. We identified two distinct amplicons on 17q23, one including TBX2 and another proximal region including RPS6KB1 (PS6K) and MUL. In addition to these previously reported overexpressed genes, we also identified amplification and overexpression of additional uncharacterized genes and ESTs, some of which suggest potential oncogenic activity. In conclusion, we have further defined two distinct regions of gene amplification and overexpression on 17q23 with identification of new potential oncogene candidates. Based on the amplification and overexpression patterns of known and as of yet unrecognized genes on 17q23, it is likely that some of these genes mapping to the discrete amplicons function as oncogenes and contribute to tumor progression in breast cancer cells.


GST isoenzymes in matched normal and neoplastic breast tissue
OĞUZTÜZÜN, SERPİL; Abu-Hijleh, A.; ÇOBAN, TÜLAY; Bulbul, D.; KILIÇ, MURAT; İŞCAN, Mümtaz; İşcan, Mesude (AEPress, s.r.o., 2011-01-01)
The potential to metabolize endogenous and exogenous substances may influence breast cancer development and tumor growth. Therefore we investigated GST activity and the protein expression of glutathione S-transferases (GSTs) isoenzymes known to be involved in the metabolism of endogenous and exogenous carcinogens in breast cancer tissue to obtain new information on their possible role in tumor progression.
An investigation of microRNAs mapping to breast cancer related genomic gain and loss regions
Selcuklu, S. D.; Yakicier, M. C.; Erson Bensan, Ayşe Elif (Elsevier BV, 2009-02-01)
Various regions of amplification or loss are observed in breast tumors as a manifestation of genomic instability. To date, numerous oncogenes or tumor suppressors on some of these regions have been characterized. An increasing body of evidence suggests that such regions also harbor microRNA genes with crucial regulatory roles in cellular processes and disease mechanisms, including cancer. Here, we investigated 35 microRNAs localized to common genomic gain and/or loss regions in breast cancers. To examine am...
Vimentin silencing effect on invasive and migration characteristics of doxorubicin resistant MCF-7 cells
Tezcan, Okan; Gündüz, Ufuk (2014-04-01)
Chemotherapy is one of the well-known treatments in cancer therapy. The effectiveness of chemotherapy is limited by several factors one of which is the emergence of multidrug resistance (MDR). One of the major mechanisms of MDR is the activity of several ATP binding cassette (ABC) transporters that pump drugs out of the cells. Doxorubicin intercalates and inhibits DNA replication; it is a powerful chemotherapeutic agent. However, it causes development of MDR in tumor cells. Vimentin is a type III intermedia...
Comparison of GST Isoenzyme Expression in Normal and Neoplastic Breast Tissue: Correlation with Clinical and Prognostic Factors
OĞUZTÜZÜN, SERPİL; İşcan, Mesude; ÖZHAVZALI, MÜZEYYEN; Sak, Serpil Dizbay (2009-01-01)
Glutathione S-transferases in breast tissue play an important role in the susceptibility to the mutagenic effects of chemical carcinogens and in the response of breast tumors to chemotherapy. In this study the immunohistochemical staining characteristics of glutathione S-transferase isoenzymes (alpha, mu, pi, and theta) were investigated in invasive duct carcinomas and in normal breast tissue of 43 patients. The relationships between the expression of the GST isoenzymes and some clinicopathological features...
Investigaton of chemopreventive properties of Urtica Dioica L., in MCF-7 and MDA231 breast cancer cell lines
Güler, Elif; İşcan, Mesude; Department of Biology (2011)
Cancer is a major health problem in developing world with mostly unsufficient treatment. Cancer prevention through dietary modification appears to be a practical and cost effective possibility. The aim of present study is to investigate the chemical components of “Urtica diocia,L (U. diocia) grown in Turkey” and the possible protective potential of its aqueous extract against breast cancer cell lines. U. diocia was extracted by maceration method which was performed for 6,12, 24, and 36 hours, at 50°C, 37°C,...
Citation Formats
A. E. Erson Bensan, S. DEMERS, J. ROUILLARD, S. HANASH, and E. PETTY, “Overexpressed genes/ESTs and characterization of distinct amplicons on 17q23 in breast cancer cells,” NEOPLASIA, pp. 521–526, 2001, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/42818.