Meme Kanserinde Survivin İfadesinin Tamoksifen Direncine Etkisi

Survivin antiapoptotik bir proteindir. Embriyonik yaşamda ve birçok tümördeyüksek düzeyde eksprese olmasına rağmen normal dokularda bulunmaz. Meme kanseri kadınlarda en sık görülen malignitedir. Meme kanserinin standart  tedavisi kemoterapi, estrojen reseptörü pozitif olan hastalarda endokrin tedavi ve HER-2 pozitif hastalıkta trastuzumab tedavilerinin birlikte veya ardışık uygulanmasıdır. Fakat bazı hastalarda endokrin tedaviye karşı direnç gelişmektedir. Bu çalışmamızda amaç survivin ekspresyonunun tamoksifen direncine olan etkisini değerlendirilmektir. 2004-2011 yılları arasında Ankara Üniversitesi Tıp Fakültesi Onkoloji Bilim dalında meme kanseri tanısı ile adjuvan tamoksifen kullanan hastalar çalışmaya alındı. Tamoksifen duyarlı ve dirençli her iki grup da 25’er hasta incelendi. Survivin ekspresyonu survivin antikorları kullanılarak immunhistokimyasal olarak değerlendirildi. Nükleer vesitoplazmik survivin ekspresyonları boyanma yüzdesine göre derecelendirildi.  Tamoksifene dirençli grup da nükleer boyanma, tamoksifen duyarlı gruptakine göre anlamlı olarak daha fazla bulunurken (p=0.045). Sitoplazmik boyanma tamoksifen duyarlı grupda daha fazla  fakat anlamlı bir fark bulunamadı (p=0.544). Nükleer survivin overekspresyonunun, tamoksifen tedavi seçiminde bir belirteç olabileceğini düşünüyoruz. Ancak bu konunun daha fazla hasta sayısı ile yapılacak çalışmalar ile aydınlatılmasına ihtiyaç vardır. Survivinin tamoksifenin indüklediği apoptozisi engelleyerek bu etkisini göstermiş olabileceğini düşünüyoruz.   Keywords – : survivin, immunhistokimya, tamoksifen direnci               Abstract,   Role of Survivin Expression İn Tamoxifen Resistance İn Patient With Early Breast Cancer   Survivin is an anti-apoptotic protein. Survivin is expressed during embryonic life and in many tumors but not in normal tissue. Breast cancer is the most common malignant tumor in women. Adjuvant tamoxifen is one of the basic endocrine treatment modalities for the operable patients with estrogen receptor positive breast cancer. However, some of the patients are resistant to tamoxifen. In the current study we aimed to evaluate the role of surviving expression in tamoxifen resistance in patients with early breast cancer. A total of consecutive fifty patients with early breast cancer diagnosed and treated between 2004 and 2011 in Ankara University School of Medicine included in the study. Patients were divided into two groups namely tamoxifen resistant (25 patients) and tamoxifen sensitive (25 patients). Nuclear and cytoplasmic survivin expression was evaluated by immunohistochemical staining. The survivin expression level was regarded as low in patients with no or less than 5% staining. The nuclear surviving expression was significantly higher in tamoxifen-resistant patients when compared to the sensitive ones (p=0.045). Though not significant, the cytoplasmic surviving staining was more prominent in tamoxifen-sensitive patients (p=0.544). In conclusion, nuclear survivin expression seems to be related with tamoxifen resistance and a favorable prognostic factor in patients with early breast cancer.

Survivin is an anti-apoptotic protein. Survivin is expressed during embryonic life and in many tumors but not in normal tissue. Breast cancer is the most common malignant tumor in women. Adjuvant tamoxifen is one of the basic endocrine treatment modalities for the operable patients with estrogen receptor positive breast cancer. However, some of the patients are resistant to tamoxifen. In the current study we aimed to evaluate the role of surviving expression in tamoxifen resistance in patients with early breast cancer. A total of consecutive fifty patients with early breast cancer diagnosed and treated between 2004 and 2011 in Ankara University School of Medicine included in the study. Patients were divided into two groups namely tamoxifen resistant (25 patients) and tamoxifen sensitive (25 patients). Nuclear and cytoplasmic survivin expression was evaluated by immunohistochemical staining. The survivin expression level was regarded as low in patients with no or less than 5% staining. The nuclear surviving expression was significantly higher in tamoxifen-resistant patients when compared to the sensitive ones (p=0.045). Though not significant, the cytoplasmic surviving staining was more prominent in tamoxifen-sensitive patients (p=0.544). In conclusion, nuclear survivin expression seems to be related with tamoxifen resistance and a favorable prognostic factor in patients with early breast cancer.