Activated hepatic stellate cells promote progression of post-heat residual hepatocellular carcinoma from autophagic survival to proliferation

Background: Microscopic residual tumor often occurs after thermal ablation for medium-large hepatocellular carcinoma (HCC), leading to early aggressive recurrence or late relapse during follow-up. The mechanism how microscopic residual HCC cells survive sublethal heat stress and develop rapid outgrowth remains poorly understood.

Methods: HCC cells were exposed to sublethal heat treatment and co-cultured with conditioned media from activated HSCs (HSC-CM). Changes of cell proliferation, parameters of cell autophagy and activation of signaling pathways in heat-treated residual HCC cells were analyzed. An HCC orthotopic model was subjected to partial thermal ablation and antitumor effects of a combined treatment regimen were studied.

Results: HCC cells survived sublethal heat stress via activation of autophagy. HSC-CM enhanced autophagic survival within 24?h and then promoted proliferation of heat-treated residual HCC cells through HGF/c-Met signaling. Inhibition of autophagy or c-Met increased apoptosis of heat-treated residual HCC cells and reversed the protective effect of HSC-CM. HGF modulated biological status in autophagic survival or proliferation of heat-treated residual HCC through HGF/c-Met/ERK signaling and downstream components of ATG5/Beclin1 or cyclinD1. In an animal model, inhibiting autophagy in combination with c-Met inhibitor significantly thwarted tumor progression of residual HCC after incomplete thermal ablation via the suppressed autophagy, the decreased proliferation and the increased apoptosis.

Conclusions: Activated HSCs promote progression of residual HCC cells after sublethal heat treatment from autophagic survival to proliferation via HGF/c-Met signaling. A combined treatment regimen of inhibiting autophagy and c-Met signaling could be used to suppress tumor progression of residual HCC after incomplete thermal ablation.     

Phytosterols Synergize With Endotoxin to Augment Inflammation in Kupffer Cells but Alone Have Limited Direct Effect on Hepatocytes

Introduction: Phytosterols are implicated in the development of parenteral nutrition–associated liver disease. A newly proposed mechanism for phytosterol‐mediated parenteral nutrition–associated liver disease is through phytosterol‐facilitated hepatic proinflammatory cytokine release following exposure to intestinally derived bacteria. Whether the proinflammatory effects are liver cell specific is not known. Aim: To determine if phytosterols cause inflammation in hepatocytes or Kupffer cells independently or require costimulation by lipopolysaccharide (LPS). Methods: In an in vivo study, neonatal piglets on parenteral nutrition for 11 days received an 8‐hour infusion of LPS. In the in vitro studies, neonatal piglet Kupffer cells and hepatocytes were treated with media, media + 1% soy oil, or media + 1% soy oil + 100µM phytosterols. After 24‐hour incubation, cells were treated with farnesoid X receptor (FXR) agonist obeticholic acid or liver X receptor (LXR) agonist GW3965 and challenged with LPS or interleukin 1β. Results: LPS administration in piglets led to transient increases in proinflammatory cytokines and suppression of the transporters bile salt export pump and ATP‐binding cassette transporter G5. In hepatocytes, phytosterols did not activate inflammation. Phytosterol treatment alone did not activate inflammation in Kupffer cells but, combined with LPS, synergistically increased interleukin 1β production. FXR and LXR agonists increased transporter expression in hepatocytes. GW3965 suppressed proinflammatory cytokine production in Kupffer cells, but obeticholic acid did not. Conclusions: LPS suppresses transporters that control bile acid and phytosterol clearance. Phytosterols alone do not cause inflammatory response. However, with costimulation by LPS, phytosterols synergistically maximize the inflammatory response in Kupffer cells.     

HGF 基因修饰的间充质干细胞对犬后肢缺血后股神经的保护作用简

目的观察携带人肝细胞生长因子基因的重组腺病毒（Ad—HGF）修饰的骨髓间充质干细胞（Msc）对犬后肢缺血后神经组织病理学的影响。方法18只犬随机分为Ad—HGF—MSC处理组、模型对照组和正常对照组,每组6只。将Ad—HGF—MSC处理组和模型对照组犬麻醉后,全结扎左后肢股动脉制作犬左后肢缺血模型,体外分离、培养犬骨髓MSC,转染Ad—HGF,并将含Ad-HGF—MSC的细胞悬液对Ad—HGF—MSC处理组犬病肢行多点肌肉注射,模型对照组犬注射等量的PBS缓冲液,正常对照组不进行任何处理。90d后,取组织标本,常规组织病理切片染色,光学显微镜下观察。结果12只犬均建模成功。模型对照组犬病侧股神经至肌束间的细小神经均发生显著退行性变,累及轴突、髓鞘和施旺细胞核。而Ad—HGF—MSC处理组犬的各级神经病变不明显,部分甚至与正常对照组无差别。结论Ad—HGF—MSC局部注射可减轻或阻遏犬后肢缺血后股神经组织损伤,具有一定的神经组织保护作用。     

腺病毒载体介导肝细胞生长因子基因对血管内皮细胞的作用

目的：研究腺病毒载体介导肝细胞生长因子（HGF）基因感染血管内皮细胞后在正常供氧、缺氧及缺氧后复氧的情况下细胞的凋亡情况。方法：将分离、培养的内皮细胞分为3组，分别给予M199（对照组）、HGF（HGF组）和HGF基因腺病毒载体（Ad-HGF组），分别在正常供氧、缺氧及缺氧后复氧3种情况下观察细胞的凋亡情况。结果：Ad-HGF组及HGF组细胞凋亡数均低于对照组（P〈0．01），Ad-HGF组与HGF组细胞凋亡数差异无显著性意义。结论：腺病毒载体介导HGF基因感染内皮细胞后能在缺氧情况下有效地阻止细胞凋亡。     

Efficient differentiation of vascular endothelial cells from dermal-derived mesenchymal stem cells induced by endothelial cell lines conditioned medium

Objective

To directionally-differentiate dermis-derived mesenchymal stem cells (DMSCs) into vascular endothelial cells (VECs) in vitro, providing an experimental basis for studies on the pathogenesis and treatment of vascular diseases.