Hypoxia-Inducible Factor-1α Regulates Chemotactic Migration of Pancreatic Ductal Adenocarcinoma Cells through Directly Transactivating the CX3CR1 Gene
Figure 2
HIF-1α directly regulated the expression of CX3CR1.
(A) MiaPaCa2 (upper) and Patu8988 (lower) cells were transfected with pcDNA3.1-HIF1α plasmids (1 µg, 2 µg) (left) or siHIF1α #2 (50 nM) (right) for 48 h and assessed by Western-blotting. (B) MiaPaCa2 (upper) and Patu8988 (lower) cells were transfected with pcDNA3.1-HIF1α plasmids (1 µg, 2 µg) (left) or siHIF1α #2 (50 nM) (right) for 48 h and assessed by semiquantitative PCR. (C) MiaPaCa2 (upper) and Patu8988 (lower) cells were transfected with pcDNA3.1-HIF1α plasmids (1 µg) (left) or siHIF1α #2 (50 nM) (right) for 48 h and assessed by confocal microscopy. Representative images for the analysis show CX3CR1 expression (in red) and nuclei (in blue) in pancreatic cancer cells. (D) MiaPaCa2 (upper) and Patu8988 (lower) cells were transfected with pcDNA3.1-HIF1α plasmids (1 µg, 2 µg) (left) or siHIF1α #2 (50 nM) (right) for 48 h and assessed in EPICS XL flow cytometry. Fluorescence was determined to measure the expression of CX3CR1. Value in control cells (pcDNA3.1 or siControl) were used as the baseline. Value in (pcDNA-HIF1α or siHIF1α #2) were shown as the fold induction in relation to the baseline.** P<0.01 versus control. (E) Immunohistochemistry of tumors originated from MiaPaCa2 cells that were transplanted in nude mice to test the effects of delivery of cholesterol-conjugated siControl (left) or siHIF1α #2 (right). (magnification: ×400).