|
|
|
| Apolipoprotein E2 inhibits mitochondrial apoptosis in pancreatic cancer cells through ERK1/2/CREB/BCL-2 signaling |
| Hui Wang a , b , Hui-Chao Zhou b , Run-Ling Ren b , Shao-Xia Du b , Zhong-Kui Guo b , Xiao-Hong Shen b , ∗ |
a Tianjin Institute of Medical & Pharmaceutical Sciences, Tianjin 300020, China
b School of Medicine, Nankai University, Tianjin 300071, China
∗Corresponding author.
E-mail address: shenxiaohong@nankai.edu.cn (X.-H. Shen). |
|
|
|
Abstract Background: Apolipoprotein E2 (ApoE2) is a pleiotropic protein that influences several aspects of cancer metabolism and development. Evading apoptosis is a vital factor for facilitating cancer cell growth. However, the role and mechanism of ApoE2 in regulating cell apoptosis of pancreatic cancer remain unclear.
Methods: In this study, we firstly detected the mRNA and protein expressions of ApoE2 in PANC-1 and Capan-2 cells by real-time polymerase chain reaction and Western blotting. We then performed TUNEL and flow cytometric analyses to explore the role of recombinant human ApoE2, pCMV6-ApoE2 and siApoE2 in the apoptosis of PANC-1 and Capan-2 cells. Furthermore, we investigated the molecular mechanism through which ApoE2 affected apoptosis in PANC-1 cells using immunofluorescence, immuno-precipitation, Western blotting and co-immunoprecipitation analysis.
Results: ApoE2 phosphorylated ERK1/2 and inhibited pancreatic cancer cell apoptosis. In addition, our data showed that ApoE2/ERK1/2 altered the expression and mitochondrial localization of BCL-2 via activating CREB. ApoE2/ERK1/2/CREB also increased the total BCL-2/BAX ratio, inhibited the opening of the mitochondrial permeability transition pore and the depolarization of mitochondrial transmembrane potential, blocked the leakage of cytochrome-c and the formation of the apoptosome, and consequently, suppressed mitochondrial apoptosis.
Conclusions: ApoE2 regulates the mitochondrial localization and expression of BCL-2 through the activation of the ERK1/2/CREB signaling cascade to evade the mitochondrial apoptosis of pancreatic cancer cells. ApoE2 may be a distinct prognostic marker and a potential therapeutic target for pancreatic cancer.
|
|
|
|
|
|
|
|
|
2023, Vol. 22 
