Combined inhibition of AURKA and HSF1 suppresses proliferation and promotes apoptosis in hepatocellular carcinoma by activating endoplasmic reticulum stress.

In this study we aimed to assess the anti-tumor effect of co-inhibition of Aurora kinase A (AURKA) and heat shock transcription factor 1 (HSF1) on hepatocellular carcinoma (HCC), as well as to explore the mechanism involved. Expression of AURKA and HSF1 in primary HCC tissues and cell lines was detected by immunohistochemistry (IHC), qRT-PCR and Western blotting. AURKA was knocked down in HepG2 and BEL-7402 HCC cells using lentivirus-mediated RNA interference. Next, CCK-8, clone formation, transwell and flow cytometry assays were used to assess their viability, migration, invasion and apoptosis, respectively. The expression of proteins related to cell cycle progression, apoptosis and endoplasmic reticulum stress (ERS) was analyzed using Western blotting. In addition, in vivo tumor growth of HCC cells was assessed using a nude mouse xenograft model, and the resulting tumors were evaluated using HE staining and IHC. Both AURKA and HSF1 were highly expressed in HCC tissues and cells, while being negatively related to HCC prognosis. Knockdown of AURKA significantly inhibited the colony forming and migrating capacities of HCC cells. In addition, we found that treatment with an AURKA inhibitor (Danusertib) led to marked reductions in the proliferation and migration capacities of the HCC cells, and promoted their apoptosis. Notably, combined inhibition of AURKA and HSF1 induced HCC cell apoptosis, while increasing the expression of ERS-associated proteins, including p-eIF2α, ATF4 and CHOP. Finally, we found that co-inhibition of AURKA and HSF1 elicited an excellent in vivo antitumor effect in a HCC mouse model with a relatively low cytotoxicity. Combined inhibition of AURKA and HSF1 shows an excellent anti-tumor effect on HCC cells in vitro and in vivo, which may be mediated by ERS. These findings suggest that both AURKA and HSF1 may serve as targets for HCC treatment.

Shen Z ，Yin L ，Zhou H ，Ji X ，Jiang C ，Zhu X ，He X ... -  《-》

ATP citrate lyase inhibitor triggers endoplasmic reticulum stress to induce hepatocellular carcinoma cell apoptosis via p-eIF2α/ATF4/CHOP axis.

ATP citrate lyase (ACLY), a key enzyme in the metabolic reprogramming of many cancers, is widely expressed in various mammalian tissues. This study aimed to evaluate the effects and mechanisms of ACLY and its inhibitor BMS-303141 on hepatocellular carcinoma (HCC). In this study, ACLY was highly expressed in HCC tissues, especially in HepG2 and Huh7 cells, but was down-regulated in Hep3B and HCC-LM3 cells. Besides, ACLY knockdown inhibited HepG2 proliferation and clone formation, while opposite result was noticed in HCC-LM3 cells with ACLY overexpression. Moreover, ACLY knockdown impeded the migration and invasion abilities of HepG2 cells. Similarly, BMS-303141 suppressed HepG2 and Huh-7 cell proliferation. The p-eIF2α, ATF4, CHOP p-IRE1α, sXBP1 and p-PERK were activated in HepG2 cells stimulated by BMS-303141. In cells where ER stress was induced, ATF4 was involved in BMS-303141-mediated cell death procession, and ATF4 knockdown reduced HCC cell apoptosis stimulated by BMS-303141. In a mouse xenograft model, combined treatment with BMS-303141 and sorafenib reduced HepG2 tumour volume and weight. In addition, ACLY expression was associated with HCC metastasis and tumour-node-metastases staging. Survival analysis and Cox proportional hazards regression model showed that overall survival was lower in HCC patients with high ACLY expression; AFP level, TNM staging, tumour size and ACLY expression level were independent risk factors affecting their overall survival. In conclusion, ACLY might represent a promising target in which BMS-303141 could induce ER stress and activate p-eIF2α/ATF4/CHOP axis to promote apoptosis of HCC cells, and synergized with sorafenib to enhance the efficacy of HCC treatment.

Zheng Y ，Zhou Q ，Zhao C ，Li J ，Yu Z ，Zhu Q ... -  《-》

AGBL2 promotes cancer cell growth through IRGM-regulated autophagy and enhanced Aurora A activity in hepatocellular carcinoma.

AGBL2 has been reported to catalyze α-tubulin detyrosination, by which it promotes tumorigenesis and cancer progression. However, its potential role in the pathogenesis of hepatocellular carcinoma (HCC) has not been revealed yet. In the present study, AGBL2 was frequently found being overexpressed in HCC tissues and cell lines. In a large cohort of clinical HCC tissues, high expression of AGBL2 was positively associated with tumor size, tumor multiplicity and advanced clinical stage (p < 0.05), and it was an independent prognostic factor for HCC patients. In HCC cell lines, ectopic overexpression of AGBL2 substantially enhanced HCC cells survival and proliferation in vitro and promoted tumor growth in vivo. In addition, we demonstrated that overexpression of AGBL2 in HCC cells notably inhibited apoptosis by enhancing IRGM-regulated autophagy. Meanwhile, AGBL2 could up-regulate the expression of TPX2 and Aurora A activity to promote cell proliferation in HCC cells. In summary, our findings suggest that up-regulation of AGBL2 plays a critical oncogenic role in the pathogenesis of HCC through modulation on autophagy and Aurora A activity, and it could be a candidate for prognostic marker and therapeutic target in HCC.

Wang LL ，Jin XH ，Cai MY ，Li HG ，Chen JW ，Wang FW ，Wang CY ，Hu WW ，Liu F ，Xie D ... -  《-》

The role of AURKA/miR-199b-3p in hepatocellular carcinoma cells.

Previous studies proved that AURKA functions as an oncogene in several cancers. This article aimed to probe the miRNA-induced regulatory mechanism of AURKA in hepatocellular carcinoma (HCC). Differentially expressed genes in TCGA-LIHC dataset were screened by bioinformatics methods. Levels of miR-199b-3p and AURKA mRNA were examined by qRT-PCR. Western blot was utilized to evaluate protein levels of AURKA, p-AKT, and AKT. Dual-luciferase assay was introduced to explore their interaction. MTT, colony formation, scratch healing, transwell, and flow cytometry assays were introduced into cell proliferation, migration, invasion, and apoptosis assessment. The impact of miR-199b-3p/AURKA axis on HCC tumor growth was determined in a tumor xenograft model. We found that AURKA was highly expressed in HCC and was coupled to poor prognosis of HCC. As manifested by cellular assays, compared to the normal cells HL-7702, AURKA presented notably high expression in HCC cell lines. Overexpressed AURKA evidently impelled the proliferation, colony formation, migration, and invasion of HCC cells while suppressing apoptosis. The regulatory gene upstream of AURKA was predicted to be miR-199b-3p by bioinformatics method, and there was a markedly negative correlation between the two. Overexpressed miR-199b-3p constrained HCC cell proliferation, migration, and invasion while fostering apoptosis, which could be counteracted by upregulating AURKA. MiR-199b-3p repressed the tumor growth in vivo by targeting AURKA and affected PI3K/AKT signaling pathway. To summarize, this study implied the regulatory mechanism of miR-199b-3p/AURKA axis in HCC, and supplied optional therapeutic targets for HCC patients.

Li G ，Tian Y ，Gao Z 《-》

miR-15b-5p induces endoplasmic reticulum stress and apoptosis in human hepatocellular carcinoma, both in vitro and in vivo, by suppressing Rab1A.

Yang Y ，Hou N ，Wang X ，Wang L ，Chang S ，He K ，Zhao Z ，Zhao X ，Song T ，Huang C ... -  《Oncotarget》