1: Lipofectamine™ 2000+pcDNA 3.1(+), PHD3: Lipofectamine™ 2000+pcDNA 3.1(+)-PHD3. Effect LEE011 cell line of

PHD3 on apoptosis of HepG2 cells To investigate whether PHD3 has an effect on inducing apoptosis in HepG2 cells, selleck screening library caspase-3 assays were performed. We found that PHD3 overexpression increased caspase-3 activity (all P = 0.00), and the cleaved 17 kD active caspase-3 fragment was visualized by western blot analysis (Figure 6A and Figure 6B). Figure 6 Activation of caspase-3. Cells transfected with the cleaved 17 kD active caspase-3 fragment of PHD3 expressed more protein than the control groups (all P =0.00). Normal: no treatment, LP2000: Lipofectamine™ 2000, PC3.1: Lipofectamine™ 2000+pcDNA 3.1(+), PHD3: Lipofectamine™ 2000+pcDNA 3.1(+)-PHD3. # P<0.05 indicates statistically significant differences in comparison

to PHD3-transfected cells. Discussion PHD3 was originally considered an HIFα regulator; it played a vital role in the progression and prognosis of cancer by targeting the degradation of HIFα. Recently, a number of studies have shown that PHD3 was closely related to cancer, independent of its hydroxylase activity. Chen, S et al. [8] found that PHD3 was highly expressed in lung cancer (NSCLC), associating with early-stage and well differentiated tumors. Fox, S. B et al. [14] showed that PHD3 expression was significantly increased after therapy with epirubicin, alone or in combination with tamoxifen, in patients with T2-4 N0-1 breast cancer; however, PHD3 expression was not relevant in treatment response and survival. Su, C et al. [6] also demonstrated that Selleckchem GDC 0449 the expression of PHD3 was significantly increased Ribose-5-phosphate isomerase from non-cancerous mucosa to cancer, and its high expression correlated with well differentiated tumors. In contrast, Couvelard, A et al. [10] discovered that high nuclear PHD3 expression related to poor survival in patients with pancreatic endocrine tumors. Gossage, L et al. [9] also found that PHD3 expression in tumor tissue indicated a worse overall

disease-free survival in ampullary adenocarcinomas and pancreatic adenocarcinomas. These studies suggested that the role of PHD3 varied from one cancer type to another and that it could be a predictor for treatment and prognosis of cancer. With an increased understanding of PHD3, more attention has been focused on its ability to suppress tumor growth [11–13]; however, little is known about PHD3’s exact mechanism. In pancreatic cells overexpressing PHD3, Su, Y et al. [13] found that apoptosis increased sharply in the presence of nerve growth factor by the activation of caspase-3. Tennant, D. A et al. [12] demonstrated PHD3-mediated alpha-ketoglutarate-induced apoptosis in three human colorectal cancer cell lines (HCT116, A431 and A375). In colorectal cancer cells, PHD3 inhibits cell growth by blocking IKKβ/NF-κ B signaling [11]. So far, the relationship between PHD3 and hepatocellular cancer (HCC) is still unclear.