ATPase抑制因子1在索拉非尼抑制肝癌射频消融后残留癌EMT中的作用机制

Residual tumor progression in hepatocellular carcinoma (HCC) after radiofrequency ablation (RFA) is an important prognostic risk factor. Our previous study demonstrated that EMT occur in residual HCC after insufficient RFA, sorafenib inhibited the EMT of residual tumor in HCC after insufficient thermal ablation, and the level of glycolysis and ATPase inhibitory factor 1 (IF1) expression were increased in HCC cells after insufficient thermal ablation. IF1 is involved in the EMT and glycolysis of tumor in HCC. So we hypothesized that sorafenib inhibits the EMT of residual tumor in HCC after insufficient thermal ablation through IF1/NFκB/Snail/E-cadherin signaling pathway. The present study was designed to verify the hypothesis by the following steps. We construct the model of HCC cell after insufficient thermal ablation in vitro. Then down- or up-regulating the expression of IF1, the effect of sorafenib on proliferation, migration, invasion, glycolysis, NFκB signaling pathways and markers associated EMT were investigated. Meanwhile, we established the model of HCC orthotopic xenograft, and the model the residual HCC after RFA. Then the effect of sorafenib on in-situ growth and metastasis of residual HCC, and the expression of IF1, E-cadherin, and IF1 were investigated. Furthermore, activating or inhibiting the activity of ERK/NFκB, the effect of sorafeinb on the expression of IF1 was observed in HCC cells after insufficient thermal ablation. If the hypothesis is verified, the mechanism of sorafenib inhibiting the EMT of residual tumor in HCC after insufficient thermal ablation would be further revealed, which provides new insight for preventing the process.

肝细胞癌（HCC）射频消融（RFA）后残留癌进展是影响其疗效的重要因素。我们前期发现，HCC不完全RFA后残留癌发生EMT；索拉非尼抑制了HCC不完全热消融后残留癌EMT；HCC细胞不完全热消融后糖酵解水平和ATPase抑制因子1（IF1）表达增加。IF1涉及肿瘤EMT和糖酵解。因此提出：IF1/NFκB/Snail/E-cadherin通路参与索拉非尼抑制HCC不完全热消融后残留癌EMT。本研究拟利用HCC细胞不完全热消融模型，敲低或过表达IF1，观察索拉非尼对HCC细胞增殖、侵袭、糖酵解、NFκB通路和EMT的影响；建立肝脏原位移植瘤RFA后残留癌模型，观察索拉非尼对残留癌生长及转移和IF1等表达的影响；激活/抑制ERK/NFκB活性，观察索拉非尼对HCC细胞不完全热消融后IF-1表达影响。该假说如获证实，将揭示索拉非尼抑制HCC不完全热消融后残留癌EMT机制，从而提高其临床防治水平。

肝细胞癌（HCC）射频消融后残留癌进展是影响其疗效的重要因素，其中涉及的机制包括上皮间充质转化、血管新生等，对其机制的进一步研究对于预防残留癌进展，提高射频消融疗效具有重要意义。主要研究内容主要为：ATP酶抑制因子1（IF1）在肝细胞癌（HCC）细胞不完全热消融后发生EMT中的作用；IF1在索拉非尼抑制HCC细胞不完全热消融后发生EMT中的作用机制；NF-kB信号通路在上述过程中的作用机制。研究发现：HepG2和SMMC7721细胞体外不完全射频消融后命名为HepG2-H和SMMC7721-H细胞；HepG2-H和SMMC7721-H细胞的增殖、迁移和侵袭能力较对照组细胞明显增强；索拉非尼抑制了HepG2和SMMC7721细胞不完全射频消融后增强的增殖、迁移和侵袭能力；索拉非尼抑制了HepG2-H和SMMC7721-H细胞的相关EMT标记物；注射HepG2-H细胞的小鼠的肿瘤体积较注射HepG2细胞的明显增大；索拉非尼抑制了肿瘤的生长。ATPase抑制因子1（IF1）、N-cadherin和CD31在裸鼠肝癌不完全射频消融后残留癌中表达升高；HepG2-H和SMMC7721-H细胞中IF1表达较HepG2和SMMC7721细胞中表达明显升高；抑制HepG2-H和SMMC7721-H中IF1表达后，其克隆形成、迁移和侵袭能力受损和其EMT相关标记N-cadherin、Snail和Vimetin明显降低；过表达HepG2和SMMC7721中IF1表达后，其克隆形成、迁移和侵袭能力增强和EMT相关标记N-cadherin、Snail和Vimetin明显升高；HCC细胞不完全热消融后通过IF1直接或间接影响肿瘤相关内皮细胞的血管新生；IF1促进了HCC细胞不完全射频消融后肿瘤生长和转移；IF1降低了体外和体内HCC细胞不完全热消融后对索拉非尼治疗的敏感性。该研究进一步解释了HCC不完全热消融后肿瘤进展的机制，并提出可联合索拉非尼和抑制IF1可预防残留癌后进展。