circRNA_101672竞争性结合FAM120A蛋白靶向调控自噬促进肝癌侵袭转移的分子机制研究

Autophagy is the key molecular basis of the metastasis of hepatocellular carcinoma (HCC).Circle RNA (circRNA) is a critical regulator of HCC autophagy which regulates the biological behaviors of malignant tumor cells by binding proteins. Our preliminary experimental discoveries indicated that circRNA_101672 expression significantly increased in the lung metastases of HCC. CircRNA_101672 could induce autophagy of HCC which is closely related to the metastasis of HCC. However, the regulation and the molecular mechanisms of circRNA_101672 in the organ-specific metastasis of HCC remain to be elucidated. Applying multi-techniques including RNA pull down, RIP (RNA binding protein immunoprecipitation), CLIP (UV-crosslinking and immunoprecipitation), EMSA (electrophoretic mobility shift assay), in vivo fluorescence imaging in animal and PCR array, the present study aims to prove our scientific hypothesis in independent experiments on cytology, animal models and clinical HCC specimens, that circRNA_101672 results in poor survival of HCC patients by competitively binding FAM120A (a RNA binding protein) via autophagy and its downstream signaling pathways. The findings achieved from the present study are supposed to elucidate a novel molecular mechanism of the metastasis of HCC promoted by the axis of circRNA_101672/FAM120A protein/autophagy and its downstream targeting genes and the interacted signaling pathways, and provide us with theoretical basis and experimental evidences to improve the prognosis of HCC patients through blocking HCC metastasis via targeting non-coding RNAs.

自噬是导致肿瘤转移的分子基础，环状RNA（circRNA）是重要的自噬调控因子，可通过与RNA结合蛋白质的相互作用调控恶性肿瘤的生物学行为。我们前期发现circRNA_101672在肝癌肺转移灶中表达显著升高，并可诱导自噬，与肝癌细胞侵袭密切相关。但circRNA_101672如何参与肝癌的自噬及器官特异性转移尚待阐明。本项目拟运用RNA pull down、RIP、CLIP、EMSA、小动物活体荧光成像、PCR array等技术，在细胞学、动物模型、临床样本三个层次，逐步验证circRNA_101672通过竞争性结合FAM120A（RNA结合蛋白），靶向调控自噬促进肝细胞癌的侵袭转移，导致肝癌预后不良。从而揭示circRNA_101672/FAM120A/自噬轴及其所调控下游细胞信号促进肝癌进展的新机制，为靶向非编码RNA，阻断肝癌侵袭转移、提高患者预后，提供理论基础和科学证据。

自噬是导致肿瘤转移的分子基础，而环状RNA（circRNA）是重要的自噬调控因子，可与RNA结合蛋白质（RBP）相互作用调控恶性肿瘤的生物学行为。我们前期发现circRNA_101672在有肺转移的肝癌（HCC）中表达升高，并诱导HCC自噬。但circRNA_101672是否及如何参与肝癌的自噬及转移尚待阐明。本项目除应用常规实验技术，还灵活运用RNA pull down、RIP、小动物活体成像、PCR array等多项先进科研手段，在细胞学、裸鼠活体模型、前瞻性/回顾性临床样本三个研究层次，逐步深入、相互验证了circRNA_101672通过竞争性结合FAM120A蛋白，靶向调控Beclin-1进而诱导HCC自噬，促进HCC侵袭转移，导致肝癌患者的不良预后。本项目的研究成果进一步明确了circRNA通过调控自噬促进肝癌进展的分子机制，为利用circRNA作为治疗靶点，阻断肝癌的转移、改善患者预后，提供理论基础和科学证据。