Department of Gastroenterology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
Carcinogenesis. 2012 Mar;33(3):555-62. doi: 10.1093/carcin/bgs002. Epub 2012 Jan 4.
A major hallmark of pancreatic ductal adenocarcinoma (PDAC) is extensive local tumor invasion and early systemic dissemination. DJ-1 has been shown to prevent cell death via the Akt pathway, thereby playing an important role in cancer progression and Parkinson's disease development. Here, we investigated the role of DJ-1 in tumor invasion and metastasis of pancreatic cancer and showed that DJ-1 is upregulated in 68.5% of pancreatic cancer specimens, correlated with tumor stage and predictive of short overall survival. Knockdown of DJ-1 expression in two PDAC cell lines reduced cell migration and invasion potential in vitro and inhibited metastasis in vivo. Knockdown of DJ-1 led to cytoskeleton disruption and diminished urokinase plasminogen activator (uPA) activity and expression, without affecting plasminogen activator inhibitor-1 and uPA receptor (uPAR) expression. All these effects were reversed by restoration of DJ-1 expression. In determining the pathway through which DJ-1 regulated cell migration and invasion, DJ-1 was found not to regulate Akt phosphorylation. Rather, it promoted extracellular signal-regulated kinase (ERK) and SRC phosphorylation. Inhibition of the ERK pathway in PDAC mimicked the effects of DJ-1 on cell migration, invasion, actin cytoskeleton and uPA/uPAR system and abolished the effects on promoting PDAC cell invasion and migration. These data represent the first identification of an important function of DJ-1, which is to regulate the invasion and metastasis properties of PDAC through the ERK/uPA cascade.
胰腺导管腺癌 (PDAC) 的一个主要特征是广泛的局部肿瘤浸润和早期全身扩散。DJ-1 已被证明可通过 Akt 途径防止细胞死亡,从而在癌症进展和帕金森病发展中发挥重要作用。在这里,我们研究了 DJ-1 在胰腺癌肿瘤侵袭和转移中的作用,并表明 DJ-1 在 68.5%的胰腺癌标本中上调,与肿瘤分期相关,并预测总生存期短。在两种 PDAC 细胞系中敲低 DJ-1 表达可降低体外细胞迁移和侵袭潜能,并抑制体内转移。DJ-1 敲低导致细胞骨架破坏,并降低尿激酶纤溶酶原激活物 (uPA) 活性和表达,而不影响纤溶酶原激活物抑制剂-1 和 uPA 受体 (uPAR) 的表达。所有这些影响均可通过 DJ-1 表达的恢复而逆转。在确定 DJ-1 调节细胞迁移和侵袭的途径时,发现 DJ-1 不调节 Akt 磷酸化。相反,它促进细胞外信号调节激酶 (ERK) 和 SRC 磷酸化。在 PDAC 中抑制 ERK 途径可模拟 DJ-1 对细胞迁移、侵袭、肌动蛋白细胞骨架和 uPA/uPAR 系统的影响,并消除对促进 PDAC 细胞侵袭和迁移的影响。这些数据首次确定了 DJ-1 的一个重要功能,即通过 ERK/uPA 级联调节 PDAC 的侵袭和转移特性。