p53 ve p73 EKSPRESYON DÜZEYİ KOLOREKTAL KANSER İÇİN TANISAL BİR BELİRTEÇ MİDİR?

Abstract

Kanser gelişiminde rolü olduğu gösterilen bazı moleküllerdeki genetik değişimler hastalık tanı, tedavi ve seyrinin takibinde belirleyici olarak kullanılabilmektedir. Kolorektal kanserlerde ise, tümör supressör genlerde meydana gelen birçok genetik değişim tam açıklanmamış olup araştırılması devam etmektedir. Bu nedenle sunulan bu çalışmada; kolorektal kanserli hastaların, normal ve tümör dokuları arasındaki p53 ve p73 geni ekspresyon düzeyi değişimlerinin belirlenmesi ve bu değişimlerin, hastalara ait klinik ve patolojik özellikler ile ilişkisinin saptanması amaçlandı. Çalışmaya, 19 kolorektal kanser hastasından alınan, 19’u normal ve 19’u tümör dokusu olmak üzere, toplam 38 kolorektal doku örneği dahil edildi. p53 ve p73 ekspresyon düzeyi analizleri, RT-PCR ve yarı ölçümsel dansitometrik analizler kullanılarak gerçekleştirildi. Normal ve tümör dokuları arasında p53 ve p73 ekspresyon düzeyleri açısından fark bulunamadı. Yüksek p53 ekspresyonu saptanan hastaların ise ileri patolojik evrelerde oldukları ancak bu hastalara ait tümörlerin metastatik olmadıkları gösterildi. Sonuç olarak, elde ettiğimiz veriler doğrultusunda, p53 ve p73 ekspresyon düzeyi değişimlerinin saptanmasının, kolorektal kanser tümör biyolojisinin anlaşılmasına katkıda bulunacağı ve hasta prognozlarının belirlenmesinde birer prediktif marker olarak kullanılabilineceği düşünülmüştür

Keywords

• Kolorektal kanser, p53, p73, ekspresyon düzeyi, RT-PCR

Are p53 and p73 Expression Levels a Diagnostic Marker in Colorectal Cancer?

Abstract

The genetic changes in some molecules that underlie malign transformation of cells can be used as markers to diagnose, monitor or characterize various forms of cancer. Though in colorectal cancer, many of the genetic changes have continued to be studied in tumor supressor genes, this study aims to clarify the expression pattern of p53, and p73 genes between normal and tumor colorectal tissues and corralate with clinicopathological features. A total of 38 tissue samples (19 normal and 19 tumor tissue)from 19 patients with colorectal cancer were included in this study. The expression of p53 and p73 have been investigated by using the RT-PCR and semi-quantitative densitometric approaches. Between the normal and tumor tissues was found no difference of p53 and p73 expression levels. In patients with high levels expression levels of p53, pathological stage was found significantly more advanced than that of the cases expressing low levels of p53, and these tumors were not metastatic. Our study suggests that the detection of expressional changes of p53, and p73 might contribute to further understanding of the tumor biology of colorectal cancer and could serve as predictive markers for patient prognosis

Keywords

• Colorectal cancer, p53, p73, expression level, RT-PCR

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