Department of Pathology and Laboratory Medicine, Tulane University Health Sciences Center, 1430 Tulane Avenue, New Orleans, LA 70112, USA.
Southeast Louisiana Veterans Health Care System, 2400 Canal Street, New Orleans, LA 70119, USA.
Cells. 2019 Oct 24;8(11):1308. doi: 10.3390/cells8111308.
Hepatitis C virus (HCV) infection triggers autophagy processes, which help clear out the dysfunctional viral and cellular components that would otherwise inhibit the virus replication. Increased cellular autophagy may kill the infected cell and terminate the infection without proper regulation. The mechanism of autophagy regulation during liver disease progression in HCV infection is unclear. The autophagy research has gained a lot of attention recently since autophagy impairment is associated with the development of hepatocellular carcinoma (HCC). Macroautophagy, microautophagy, and chaperone-mediated autophagy (CMA) are three autophagy processes involved in the lysosomal degradation and extracellular release of cytosolic cargoes under excessive stress. Autophagy processes compensate for each other during extreme endoplasmic reticulum (ER) stress to promote host and microbe survival as well as HCC development in the highly stressed microenvironment of the cirrhotic liver. This review describes the molecular details of how excessive cellular stress generated during HCV infection activates CMA to improve cell survival. The pathological implications of stress-related CMA activation resulting in the loss of hepatic innate immunity and tumor suppressors, which are most often observed among cirrhotic patients with HCC, are discussed. The oncogenic cell programming through autophagy regulation initiated by a cytoplasmic virus may facilitate our understanding of HCC mechanisms related to non-viral etiologies and metabolic conditions such as uncontrolled type II diabetes. We propose that a better understanding of how excessive cellular stress leads to cancer through autophagy modulation may allow therapeutic development and early detection of HCC.
丙型肝炎病毒(HCV)感染会触发自噬过程,有助于清除功能失调的病毒和细胞成分,否则这些成分会抑制病毒复制。细胞自噬增加可能会杀死受感染的细胞并终止感染,但如果没有适当的调节,情况就会如此。HCV 感染中肝脏疾病进展过程中自噬调节的机制尚不清楚。自噬研究最近引起了很多关注,因为自噬功能障碍与肝细胞癌(HCC)的发展有关。巨自噬、微自噬和伴侣介导的自噬(CMA)是三种自噬过程,涉及在过度应激下溶酶体降解和细胞溶质货物的细胞外释放。在极端内质网(ER)应激下,自噬过程相互补偿,以促进宿主和微生物的存活,以及肝硬化肝脏高度应激微环境中的 HCC 发展。本文描述了 HCV 感染期间产生的过度细胞应激如何激活 CMA 以提高细胞存活率的分子细节。讨论了与 HCC 相关的病理意义,即在患有 HCC 的肝硬化患者中,应激相关 CMA 激活导致肝脏先天免疫和肿瘤抑制因子丢失。通过细胞质病毒引发的自噬调节的致癌细胞编程可能有助于我们理解与非病毒病因和代谢状况(如失控的 2 型糖尿病)相关的 HCC 机制。我们提出,更好地了解过度细胞应激如何通过自噬调节导致癌症,可能有助于开发治疗方法和早期检测 HCC。