Role of CYB5A in Pancreatic Cancer Prognosis and Autophagy Modulation
Role of CYB5A in Pancreatic Cancer Prognosis and Autophagy Modulation
复制标题
DOI：
10.1093/jnci/djt346
复制
发表时间：
2014-01-01
影响因子：
10.3
通讯作者：
Giaccone, Giuseppe
中科院分区：
文献类型：
--
作者：
Giovannetti, Elisa;Wang, Qiuyan;Giaccone, Giuseppe
背景 18q22.3 缺失是胰腺导管腺癌 (PDAC) 的一个预后标志物。本研究调查了该细胞带编码的基因。方法我们研究了根治性切除患者 (n = 130) 和转移性患者 (n = 50) 的 mRNA/蛋白质表达。使用伤口愈合、侵袭、膜联蛋白-V、电子显微镜和自噬测定以及自噬基因和激酶阵列，通过逆转录病毒介导的上调和小干扰 RNA，在 11 个 PDAC 细胞系和 5 个原代培养物中测试了 CYB5A 的作用。通过 Firefly 和 Gaussia 荧光素酶生物发光、磁共振成像和高频超声监测 CYB5A+ 原位模型（n = 6 只小鼠/组）。通过 t 检验、Fisher 精确检验、对数秩检验和 Cox 比例风险模型对数据进行分析。所有统计检验均为双侧。结果 CYB5A mRNA 或蛋白表达低的切除和转移患者的生存期均具有统计学意义的显着缩短（例如，中位 = 16.7 个月，95% 置信区间 [CI] = 13.5 至 19.9；vs 中位 = 24.8 个月，95% CI = 12.8 至 36.9；P = .02，两侧时序检验；n = 82 例根治性切除的 PDAC），多变量分析证实了预后相关性。此外，我们还鉴定了 CYB5A 的新功能，即自噬诱导，同时减少 PDAC 细胞的增殖和迁移/侵袭。促自噬通路的网络分析表明 CYB5A 与 TRAF6 相互作用，这通过 CYB5A 重建后 TRAF6 下调得到证实（SU.86.86-CYB5A+ 中为-69%；P = .005，双边 t 检验）。 CYB5A 沉默具有相反的效果，恢复 TRAF6 表达和伤口愈合。体内研究表明，CYB5A 诱导自噬，同时抑制肿瘤生长/转移并提高生存率（中位 = 57 天，95% CI = 52 至 61；vs 中位 = 44 天，95% CI = 21 至 57；P = 0.03，双边时序检验）。 结论 这些结果将 CYB5A 定义为 PDAC 的一种新型预后因素，可发挥其作用通过自噬诱导和 TRAF6 调节发挥肿瘤抑制功能。
Background Loss of 18q22.3 is a prognostic marker in pancreatic ductal adenocarcinoma (PDAC). This study investigated genes encoded by this cytoband.Methods We studied mRNA/protein expression in radically resected (n = 130) and metastatic patients (n = 50). The role of CYB5A was tested in 11 PDAC cell lines and five primary cultures through retrovirus-mediated upregulation and small interfering RNA using wound-healing, invasion, annexin-V, electron microscopy, and autophagic assays, as well as autophagy genes and kinases arrays. CYB5A+ orthotopic models (n = 6 mice/group) were monitored by Firefly and Gaussia-luciferase bioluminescence, magnetic resonance imaging, and high-frequency ultrasound. Data were analyzed by t test, Fisher exact-test, log-rank test and Cox proportional hazards models. All statistical tests were two-sided.Results Both resected and metastatic patients with low mRNA or protein expression of CYB5A had statistically significantly shorter survival (eg, median = 16.7 months, 95% confidence interval [CI] = 13.5 to 19.9; vs median = 24.8 months, 95% CI = 12.8 to 36.9; P = .02, two-sided log-rank test; n = 82 radically resected PDACs), and multivariable analyses confirmed prognostic relevance. Moreover, we characterized a novel function to CYB5A, autophagy induction, concomitant with reduced proliferation and migration/invasion of PDAC cells. Network analysis of proautophagic pathways suggested CYB5A interaction with TRAF6, which was confirmed by TRAF6 downregulation after CYB5A reconstitution (-69% in SU.86.86-CYB5A+; P = .005, two-sided t test). CYB5A silencing had opposite effects, restoring TRAF6 expression and wound healing. In vivo studies showed that CYB5A induced autophagy while inhibiting tumor growth/metastasis and increasing survival (median = 57 days, 95% CI = 52 to 61; vs median = 44 days, 95% CI = 21 to 57; P = .03, two-sided log-rank test).Conclusions These results define CYB5A as a novel prognostic factor for PDAC that exerts its tumor-suppressor function through autophagy induction and TRAF6 modulation.