AZGP1在结直肠癌复发转移中的作用及机制研究

To identify the serum proteins involved in CRC carcinogenesis, differentially expressed proteins among serum of colorectal cancer, adenoma,healthy control were investigated by a two-dimensional gel electrophoresis and Nano-LC-ESI-Q-TOF-based proteomics approach. AZGP1 was found to be elevated in CRC serum and adenoma serum compared with normal serum. The elevated expression of AZGP1 in CRC serum and adenoma was confirmed by Elisa analysis. There was a significant drop in AZGP1 levels after the removal of tumour. These findings suggest that the high level of AZGP1 in CRC serum is correlated with CRC carcinogenesis and progression. We also found an increase serum level in CRC with liver metastasis compared with CRC without liver metastasis. Overall survival(OS) and Disease-free survival (DFS) was better in patients with low AZGP1 level than in high level.All these results indicated that AZGP1 might play an important role in the recurrence and metastasis of CRC. Realtime PCR and Immunohistochemical analysis on tissue microarray showed that the expression of AZGP1 in CRC tissues was higher than in normal and adenoma tissues, and the elevated expression of AZGP1 was correlated with metastasis of CRC and the decreased survival rate of CRC patients. In CRC cell line SW480, stable overexpression of AZGP1 promoted cell motility and invasion in vitro. The aim of present study is to investigate the feasibility of AZGP1 in the serum as a prognostic marker for CRC, and to investigate the impact of AZGP1 on CRC recurrence and metastasis and its potentional molecular mechanism.

在前期血清蛋白质组学研究中,我们发现1.AZGP1在结直肠癌（CRC）患者血清中的表达显著高于健康对照和腺瘤患者,在CRC术前血清中的表达显著高于术后.2.AZGP1在CRC患者血清及组织中的表达与肝转移显著相关,与患者总生存及无疾病存活呈负相关。3.AZGP1过表达促进SW480细胞的侵袭和迁移。综上说明AZGP1与CRC复发转移密切相关。然而,AZGP1在CRC复发转移中的作用及机制尚不明确。本研究拟通过对AZGP1基因进行沉默/过表达干预,利用基因芯片、免疫共沉淀及体外结合技术深入研究AZGP1在CRC生长、转移中的作用及其可能参与的信号传导通路;运用Elisa及IHC扩大样本且前瞻性地验证AZGP1预测CRC复发转移的准确性和可靠性。通过本研究,以期为CRC 术后复发转移的预测提供新的可靠的分子标志物,使低危复发转移病人免受化疗之苦，节约大量医疗资源，以期实现CRC术后治疗个体化。

结直肠癌（Colorectal Cancer，CRC）是常见的恶性肿瘤之一，发病率和死亡率均有逐年上升的趋势。近年来，虽然结直肠癌的诊断、治疗取得了一些长足的进展，但5年总生存率仍仅为55%左右，结直肠癌根治手术后复发是结直肠癌术后死亡的主要原因。因此,早期预测复发转移的高危因素，对改善患者的预后,提高其生存质量具有重要的现实意义。目前没有一个特异性好、灵敏度高的分子标志物能够准确地预测结直肠癌的手术后复发转移。由于不能区分复发的高危因素，按照规范指南，许多病人都接受了术后的辅助的化疗，而真正获益的仅是那些潜在的有复发转移趋势的病人。我们以往的研究表明， AZGP1在结直肠癌组织和血清中均升高，并与预后负相关。本研究的目的是探讨血清AZGP1做为结直肠癌预后预测指标的可行性，并探讨其对结直肠癌复发的影响和潜在的分子机制。体内体外的实验结果表明AZGP1增强CRC细胞的生长、侵袭和转移。ITGAV被证明是AZGP1的相互作用蛋白。AZGP1 通过与ITGAV相互作用调节了AMPK 通路。通过样本验证和前瞻性研究，探讨了血清中AZGP1作为 CRC复发转移预测的可行性。ROC曲线分析显示血清AZGP1能较好的预测复发转移。我们的研究结果可能为开发新的生物标志物用于CRC的预后预测提供一些有用的信息。这一发现可能有助于我们识别和选择高危患者进行手术后有效和积极的治疗。