Expression Profiles of Apoptosis Related Genes and Investigation of HIF-2α Signal Transduction in the Ovarian Cancer Cell Line OvCa-3

Zusammenfassung

Das Tumorsuppressorgen VHL ist ein wichtiger Regulator sowohl von Bcl-2A als auch von HIF-2α. Mit dieser Studie sollte die Frage geklärt werden, ob VHL die HIF-2α-Expression in der Ovarialkarzinom-Zelllinie OvCa-3 über einen Bcl-2A-abhängigen Weg reguliert. Des Weiteren wurde die Expression verschiedener Tumorsuppressorgene, Bcl-2-Familienmitglieder und Hypoxie-abhängiger Transkriptionsfaktoren (HIF) untersucht. Hierzu wurde die Genfunktion von Bcl-2A mittels eines RNA interference assay ausgeschaltet. Die Expression von HIF-2α wurde dann mit einer TaqMan-Realtime-PCR-Analyse quantifiziert. Zusätzlich wurde die Expression verschiedener Tumorsuppressorgene, Bcl-2-Familienmitglieder und Hypoxie-abhängiger Transkriptionsfaktoren (HIF) mittels RT‐PCR nachgewiesen. Es gelang der Nachweis der Expression der Tumorsuppressorgene RB-1, VHL, NF-1, NF-2, Wt-1, p53 und APC, des Hypoxie-induzierten Faktors HIF-2α, und der Bcl-2 Familienmitglieder Bax, Bcl-2A und Bclx in OvCa-3-Zellen. Nach dem Ausschalten der Genfunktion von Bcl-2A ergab die Quantifizierung der HIF-2α-Expression keine signifikante Veränderung. Es ist deshalb davon auszugehen, dass VHL die Expression von HIF-2α in OvCa-3-Zellen nicht über einen Bcl-2A-abhängigen Weg reguliert. Darüber hinaus ist zu vermuten, dass Bcl-2A nicht in die Signaltransduktion von HIF-2α in OvCa-3-Zellen involviert ist.

Abstract

Since the tumor suppressor gene VHL is an important regulator of Bcl-2A as well as of HIF-2α, we wanted to address the question whether VHL regulates the expression of HIF-2α in the ovarian cancer cell line OvCa-3 via Bcl-2A dependent pathways. Furthermore, we investigated expression of different tumor suppressor genes, Bcl-2 family members and hypoxia inducible factors. Gene function of Bcl-2A was knocked down using RNA interference assay. Quantification of HIF-2α expression was performed by TaqMan-Realtime-PCR analysis. In addition, transcript levels of different tumor suppressor genes, Bcl-2 family members and hypoxia inducible factors were determined by RT‐PCR. We demonstrate expression of the tumor suppressor genes RB-1, VHL, NF-1, NF-2, Wt-1, p53, and APC, hypoxia dependent factor HIF-2α, and the Bcl-2 family members Bax, Bcl-2A, and Bclx in OvCa-3 cells. Furthermore, gene function of Bcl-2A was knocked down. After knock-down of Bcl-2A, expression of HIF-2α was quantified using TaqMan-Realtime-PCR-analysis revealing no significant change. We suggest that VHL is not regulating the expression of HIF-2α via Bcl-2A dependent pathways in OvCa-3 cells. Furthermore, we hypothesise that Bcl-2A might not be involved in the signal transduction of HIF-2α in OvCa-3 cells.

Schlüsselwörter

Apoptose - HIF-2α - Bcl-2A - OvCa-3-Zellen - Tumorsuppressorgene

Key words

Apoptosis - HIF-2α - Bcl-2A - OvCa-3 cells - tumor suppressor genes

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