Department of Surgery, Hammersmith Hospital, Imperial College London, London, UK.
MiNA Therapeutics Ltd., London, UK.
Adv Exp Med Biol. 2017;983:189-194. doi: 10.1007/978-981-10-4310-9_13.
The prognosis for hepatocellular carcinoma (HCC) remains poor and has not improved in over two decades. Most patients with advanced HCC who are not eligible for surgery have limited treatment options due to poor liver function or large, unresectable tumors. Although sorafenib is the standard-of-care treatment for these patients, only a small number respond. For the remaining, the outlook remains bleak. A better approach to target "undruggable" molecular pathways that reverse HCC is therefore urgently needed. Small activating RNAs (saRNAs) may provide a novel strategy to activate expression of genes that become dysregulated in chronic disease. The transcription factor CCAAT/enhancer-binding protein alpha (C/EBPα), a critical regulator of hepatocyte function, is suppressed in many advanced liver diseases. By using an saRNA to activate C/EBPα, we can exploit the cell's own transcription machinery to enhance gene expression without relying on exogenous vectors that have been the backbone of gene therapy. saRNAs do not integrate into the host genome and can be modified to avoid immune stimulation. In preclinical models of liver disease, treatment with C/EBPα saRNA has shown reduction in tumor volume and improvement in serum markers of essential liver function such as albumin, bilirubin, aspartate aminotransferase (AST), and alanine transaminase (ALT). This saRNA that activates C/EBPα for advanced HCC is the first saRNA therapy to have entered a human clinical trial. The hope is that this new tool will help break the dismal 20-year trend and provide a more positive prognosis for patients with severe liver disease.
肝细胞癌 (HCC) 的预后仍然很差,二十多年来没有改善。由于肝功能不佳或肿瘤较大无法切除,大多数不符合手术条件的晚期 HCC 患者的治疗选择有限。索拉非尼虽然是这些患者的标准治疗方法,但只有少数患者有反应。对于其余患者,前景仍然黯淡。因此,迫切需要找到一种更好的方法来靶向逆转 HCC 的“不可成药”分子途径。小激活 RNA (saRNA) 可能为激活慢性疾病中失调基因的表达提供一种新策略。转录因子 CCAAT/增强子结合蛋白α (C/EBPα) 是肝细胞功能的关键调节因子,在许多晚期肝脏疾病中受到抑制。通过使用 saRNA 激活 C/EBPα,我们可以利用细胞自身的转录机制来增强基因表达,而无需依赖一直是基因治疗基础的外源载体。saRNA 不会整合到宿主基因组中,并且可以进行修饰以避免免疫刺激。在肝脏疾病的临床前模型中,用 C/EBPα saRNA 治疗可减少肿瘤体积并改善白蛋白、胆红素、天冬氨酸转氨酶 (AST) 和丙氨酸转氨酶 (ALT) 等重要肝功能的血清标志物。这种用于晚期 HCC 的激活 C/EBPα 的 saRNA 是第一个进入人体临床试验的 saRNA 疗法。希望这种新工具将有助于打破 20 年来的低迷趋势,为严重肝脏疾病患者提供更积极的预后。