HCT116 Hücrelerinde Floropirimidinlere Karşı p67phox'un Fazla Ekspresyonu

Giriş: Kanser hücreleri büyüme hızı ile başa çıkmak için reaktif oksijen türlerine (ROS) ihtiyaç duyarlar. Antikanser ilaçları tarafından indüklenen ROS'un akümülasyonu oksidatif hasarla hücre ölümünü kolaylaştırabilir. Potansiyel bir ROS kaynağı tek fonksiyonu ROS üretmek olan NADPH oksidaz (NOX) enzimidir. Bu çalışmada insan kolon kanseri hücre hattı olan HCT116 da floropirimidinlere karşı NOX1 ve NOX2'nin ekspresyonunu araştırmayı amaçladık. Yöntemler: Antikanser ilaçlar olarak floropirimidinleri; 5-florourasil (FUra) ve 5'-floro-2'-deoksiuridin (FdUrd) kullandık ve sırasıyla semi-kantitatif polimeraz zincir reaksiyonu (PCR), kantitatif PCR (qPCR) ve mikroarray metodları ile NOX1 ve NOX2'nin mRNA seviyelerini ölçtük. Bulgular: p67phox hariç enzimin hiçbir alt ünitesinin ekspresyonunun FUra ve FdUrd'ye karşı değişmediğini bulduk. p67phox ekspresyonu ilaçlarla bazal seviyelere nazaran yaklaşık 25 kat indüklendi. Sonuç: p67phox alt ünitesi ilaçlarla muamele sonrasında NOX ile üretilen ROS'da önemli bir alt ünite olabilir.

Overexpression of p67phox in Response to Fluoropyrimidines in HCT116 Cells

Objectives: Cancer cells require reactive oxygen species (ROS) in order to keep up with growth rate. The accumulation of ROS induced by anticancer drugs can promote cell death through oxidative damage. A potential source of ROS is the family of NADPH oxidase (NOX) enzyme that produces ROS as their sole function. In this study, we aimed to investigate expression of NOX1 and NOX2 subunits in response to fluoropyrimidines in human colon cancer cell line, HCT116. Methods: We used fluoropyrimidines, 5-fluorouracil (FUra) and 5'-fluoro-2'-deoxyuridine (FdUrd) as anticancer drugs, and measured mRNA levels of NOX1 and NOX2 with semi-quantitative polymerase chain reaction (PCR), quantitative PCR (qPCR) and microarray assays in order. Results: We found that expression of none of enzyme subunits was altered in response to FUra or FdUrd, except expression of p67phox. Expression of p67phox was induced by drugs approximately 25-fold relative to basal level. Conclusion: p67phox subunit may be a key subunit in NOX-mediated ROS production following exposure to drugs.

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