肝细胞癌（HCC）是全球癌症相关死亡的第三大原因。由于缺乏对发病机制的充分了解，晚期 HCC 的治疗选择有限。细胞衰老是细胞周期停滞的一种状态，在肝癌的发病机制中发挥着重要作用。肝细胞衰老的机制尚不完全清楚。 LncRNA NEAT1 作为癌基因，有助于 HCC 的发展。 NEAT1 是否调节 HCC 中的肝细胞衰老尚不清楚。在体外和体内评估了 NEAT1 和 KIF11 在 HCC 细胞衰老和肿瘤生长中的作用。采用 RNA Pulldown、质谱、染色质免疫沉淀 (ChIP)、荧光素酶报告基因检测、RNA FISH 和免疫荧光 (IF) 染色来探讨 NEAT1 和 KIF11 在 HCC 细胞衰老中的详细分子机制。我们发现 NEAT1 在肿瘤中上调组织和肝癌细胞，与编码 p16INK4a 和 p14ARF 蛋白的衰老生物标志物 CDKN2A 呈负相关。在阿霉素 (DOXO) 或血清饥饿诱导的衰老肝癌细胞中，NEAT1 减少。此外，NEAT1 缺陷会导致培养的肝癌细胞衰老，并在小鼠模型中防止 HCC 的进展。在衰老过程中，NEAT1 易位到细胞质中并与运动蛋白 KIF11 相互作用，导致 KIF11 蛋白降解，并随后在培养的肝癌细胞中增加 CDKN2A 的表达。此外，KIF11 敲低会导致培养的肝癌细胞衰老。肝细胞中 Kif11 的基因缺失抑制了小鼠模型中 HCC 的发展。 总之，NEAT1 过表达可减少 HCC 组织和肝癌细胞的衰老并促进肿瘤进展，而 NEAT1 缺陷会导致 HCC 中的衰老并抑制肿瘤进展。这与 KIF11 依赖性 CDKN2A 抑制有关。这些发现为通过抑制 NEAT1 和 KIF11 或诱导衰老来开发 HCC 潜在疗法奠定了基础。© 2023 作者。约翰·威利出版的《临床与转化医学》

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths worldwide. Therapeutic options for advanced HCC are limited, which is due to a lack of full understanding of pathogenesis. Cellular senescence is a state of cell cycle arrest, which plays important roles in the pathogenesis of HCC. Mechanisms underlying hepatocellular senescence are not fully understood. LncRNA NEAT1 acts as an oncogene and contributes to the development of HCC. Whether NEAT1 modulates hepatocellular senescence in HCC is unknown.The role of NEAT1 and KIF11 in cellular senescence and tumor growth in HCC was assessed both in vitro and in vivo. RNA pulldown, mass spectrometry, Chromatin immunoprecipitation (ChIP), luciferase reporter assays, RNA FISH and immunofluorescence (IF) staining were used to explore the detailed molecular mechanism of NEAT1 and KIF11 in cellular senescence of HCC.We found that NEAT1 was upregulated in tumor tissues and hepatoma cells, which negatively correlated with a senescence biomarker CDKN2A encoding p16INK4a and p14ARF proteins. NEAT1 was reduced in senescent hepatoma cells induced by doxorubicin (DOXO) or serum starvation. Furthermore, NEAT1 deficiency caused senescence in cultured hepatoma cells, and protected against the progression of HCC in a mouse model. During senescence, NEAT1 translocated into cytosol and interacted with a motor protein KIF11, resulting in KIF11 protein degradation and subsequent increased expression of CDKN2A in cultured hepatoma cells. Furthermore, KIF11 knockdown caused senescence in cultured hepatoma cells. Genetic deletion of Kif11 in hepatocytes inhibited the development of HCC in a mouse model.Conclusively, NEAT1 overexpression reduces senescence and promotes tumor progression in HCC tissues and hepatoma cells, whereas NEAT1 deficiency causes senescence and inhibits tumor progression in HCC. This is associated with KIF11-dependent repression of CDKN2A. These findings lay the foundation to develop potential therapies for HCC by inhibiting NEAT1 and KIF11 or inducing senescence.© 2023 The Authors. Clinical and Translational Medicine published by John Wiley & Sons Australia, Ltd on behalf of Shanghai Institute of Clinical Bioinformatics.