PETEK BALLAR KIRMIZIBAYRAK, BURCU ERBAYKENT TEPEDELEN

Endoplazmik retikulum-aracılı protein yıkım yolağında görev yapan p97/VCP ve Ufd1-Npl4 adlı proteinlerin NF-κB yolağına etkisinin prostat kanser hücre hattında incelenmesi

Amaç: Bu çalışmada, endoplazmik retikulum-aracılı yıkım yolağındaki retrotranslokasyon basamağının anahtar proteini olan p97/VCP ve etkileşim partnerleri olan Ufd1 ve Npl4 proteinlerinin NF-κB yolağı üzerine etkileri prostat kanser hücre hattında incelendi. Gereç ve Yöntem: p97/VCP, Ufd1 ve Npl4 ifadeleri RNA interferans RNAi (RNA interferans) teknolojisi ile LNCAP hücrelerinde susturuldu ve NF-κB aktivitesi ikili lusiferaz yöntemi ile NF-κB yolağı proteinlerinin ifadesi ise immünoblotlama ile değerlendirildi. Bulgular: p97/VCP, Ufd1 ve Npl4 ifadelerinin susturulması LNCaP hücrelerinde NF-κB aktivitesini anlamlı olarak azaltmış ve IκBα protein seviyesini arttırırken fosforile NF-κB ve fosforile IκBα seviyelerini azaltmıştır. Sonuç: Retrotranslokasyon kompleks üyelerinin susturulması ile LNCaP hücrelerinde NF-κB aktivitesinin azalmasının NF-κB inhibitörü olan IκBα seviyesinin artmasına bağlı olduğu düşünülmektedir. Bulgularımız p97/VCP ve etkileşim partnerleri Ufd1-Npl4 proteinlerinin prostat kanserinde NF-κB yolağının düzenlenmesinde önemli bir etken olabileceğini önermektedir.

Investigating the effect of p97/VCP and Ufd1-Npl4 proteins functioning in the endoplasmic reticulum-associated degradation on the NF-κB pathway

Aim: In this study, the effects of p97/VCP and its interacting partners Ufd1 and Npl4 proteins, which function at the retrotranslocation step of endoplasmic reticulum-associated degradation were investigated on the NF-κB pathway in the prostate cancer cell line. Materials and Methods: The expressions of p97/VCP, Ufd1 and Npl4 were silenced in LNCaP cells using RNAi (RNA interference) technology. NF-κB activity was evaluated by dual luciferase assay system and the expression of NF-κB pathway proteins were investigated using immunoblotting. Results: Silencing of expression of p97/VCP, Ufd1 and Npl4 significantly diminished NF-κB activity and increased the level of IκBα protein while decreased phosphorylated NF-κB and phosphorylated IκBα levels in LNCaP cells. Conclusion: The decrease NF-κB activity upon silencing the expressions of retrotranslocation complex members in LNCaP cells might be associated with the increased level of NF-κB inhibitor IκBα. Our data suggests that p97/VCP and its interacting partners might be important factors on the regulation of NF-κB pathway in the prostate cancer.

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