Chen Tian, Xiang Lunjian, Zhang Wenjin, Xia Zhenyi, Chen Weixian
Department of Laboratory Medicine, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China.
Hepatobiliary Surgery, Chongqing University Three Gorges Hospital, Chongqing, People's Republic of China.
J Hepatocell Carcinoma. 2024 Aug 24;11:1623-1639. doi: 10.2147/JHC.S470250. eCollection 2024.
Alanine glyoxylate aminotransferase (AGXT) family members are crucial in cancer processes, but their role in hepatocellular carcinoma (HCC) metabolism is unclear. This study investigates AGXT2's function in HCC.
AGTX2 expression was studied using bioinformatics, real-time reverse transcriptase-polymerase chain reaction (RT-qPCR), Western blot, and Enzyme-linked immunosorbent assay (ELISA). A lentivirus-induced AGTX2 overexpression cell model was analyzed with RNA sequencing (RNA-seq) and liquid chromatography-mass spectrometry (LC-MS). Cholesterol levels were confirmed by Oil Red O staining. AGTX2 effects were evaluated through cell cycle analysis, wound healing, and transwell migration assays.Tumorigenic effects were observed in NOD-SCID IL2Rγnull (NTG) mice in subcutaneous experiments. Protein interaction was examined through co-immunoprecipitation methods.
We observed a significant reduction in AGXT2 mRNA and protein levels in both HCC tumor tissues and serum samples from patients with liver cancer, which was associated with a worse prognosis. The activation of has been shown to effectively decrease cholesterol levels in liver cancer cells, serving as an antagonist in the cholesterol metabolism pathway. An increase in low density lipoprotein receptor ( mRNA was noted in cells overexpressing AGXT2, accompanied by a decrease in LDLR protein and an elevation in proprotein convertase subtilisin/kexin type 9 () mRNA and protein levels. Molecular docking and co-immunoprecipitation experiments further elucidated the interaction between AGXT2 and LDLR proteins. AGXT2 was observed to suppress the migratory and invasive capabilities of HCC cells, inducing cell cycle arrest in the G2/M phase. AGXT2 activation inhibited subcutaneous liver cancer tumor growth in NTG mice.
AGXT2 was found to lower cholesterol levels in liver cancer cells, possibly through interactions with the LDLR protein and modulation of PCSK9-mediated LDLR degradation. This mechanism may impede cholesterol transport to liver cancer cells, thereby suppressing their growth and metastasis.
丙氨酸乙醛酸氨基转移酶（AGXT）家族成员在癌症进程中至关重要，但其在肝细胞癌（HCC）代谢中的作用尚不清楚。本研究调查AGXT2在HCC中的功能。
采用生物信息学、实时逆转录聚合酶链反应（RT-qPCR）、蛋白质印迹法和酶联免疫吸附测定（ELISA）研究AGXT2的表达。用RNA测序（RNA-seq）和液相色谱-质谱联用（LC-MS）分析慢病毒诱导的AGXT2过表达细胞模型。通过油红O染色确认胆固醇水平。通过细胞周期分析、伤口愈合和Transwell迁移试验评估AGXT2的作用。在皮下实验中观察NOD-SCID IL2Rγnull（NTG）小鼠的致瘤作用。通过免疫共沉淀方法检测蛋白质相互作用。
我们观察到HCC肿瘤组织和肝癌患者血清样本中AGXT2 mRNA和蛋白质水平显著降低，这与较差的预后相关。已证明 的激活可有效降低肝癌细胞中的胆固醇水平，在胆固醇代谢途径中起拮抗剂作用。在过表达AGXT2的细胞中，低密度脂蛋白受体（LDLR）mRNA水平升高，同时LDLR蛋白水平降低，前蛋白转化酶枯草溶菌素/kexin 9型（PCSK9）mRNA和蛋白质水平升高。分子对接和免疫共沉淀实验进一步阐明了AGXT2与LDLR蛋白之间的相互作用。观察到AGXT2抑制HCC细胞的迁移和侵袭能力，诱导细胞周期停滞在G2/M期。AGXT2激活抑制NTG小鼠皮下肝癌肿瘤生长。
发现AGXT2可能通过与LDLR蛋白相互作用并调节PCSK9介导的LDLR降解来降低肝癌细胞中的胆固醇水平。该机制可能阻碍胆固醇向肝癌细胞的转运，从而抑制其生长和转移。
