Fig. 5: TET1 activates AKT signaling by the CK2-mediated PTEN inactivation.
From: Hypoxia switches TET1 from being tumor-suppressive to oncogenic
Western blot analysis of TET1, p-PTENS370, PTEN, p-AKTT308 and t-AKT in 8505C (A) and C643 (B) cells with the indicated treatments. The PIP3 phosphatase assay was performed to detect PTEN activity in 8505C (C) and C643 (D) cells with the indicated treatments (n = 3 biological replicates). The idle PTEN activity was shown as mean ± SD; unpaired Student’s test; *p < 0.05. Western blot analysis of CK2α and β in 8505C (E) and C643 (F) cells with the indicated treatments. G Western blot analysis of TET1, p-AKTS473, p-AKTT308, t-AKT, p-GSK3β, GSK3α/β, p-β-catenin, β-catenin and HIF1α in 8505C cells with the indicated treatments. Cells were treated with CK2 inhibitor CX-4945 at the indicated concentration for 24 h. The densitometry ratio of the indicated proteins to β-actin (loading control) was shown below the corresponding band. H The IHC staining for p-Pten at S370 and Ck2β (upper panel) and their quantification (lower panel) in mice with the indicated genotypes. I A schematic model concluding that TET1 activates AKT signaling by the CK2-mediated PTEN inactivation under hypoxia. Dox− negative control, Dox+ cells inducibly expressing TET1, sgCon control cells, sgTET1 TET1-knockout C643 cells. Scale bare in IHC pictures, 50 μm. Brafm/+ Braf heterozygous mutation, Tet1+/+ Tet1 wild-type, Tet1−/− Tet1 homozygous deletion. Rank scores were estimated [i.e., “negative” (−), “weak” (+), “moderate” (++), and “strong” (+++)]. Graph shows the proportion of each score for different groups.
