Department of General Surgery, Beijing Tiantan Hospital, Capital Medical University, No. 119, South 4th Ring West Road, Fengtai District, Beijing, 100070, China.
Cell Mol Biol Lett. 2021 Nov 27;26(1):49. doi: 10.1186/s11658-021-00295-4.
Hepatocellular carcinoma (HCC) is now the second leading cause of cancer death worldwide and lacks effectual therapy due to its high rate of tumor recurrence and metastasis. The aim of this study was to investigate the effects of L antigen family member 3 (LAGE3, a member of the LAGE gene family involved in positive transcription) on the progression of HCC.
The expression of LAGE3 was detected by quantitative real-time polymerase chain reaction. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, colony formation assay, EdU, and cell cycle analysis assay were employed to evaluate the proliferation of HCC cells. Annexin V-FITC/PI and TUNEL assay were used to assess the apoptosis rate of HCC cells. Wound healing and transwell assay were used to investigate the migration and invasion of HCC cells. A xenograft model of HCC was established with 2 × 10 Hep3B or SK-HEP1 cells to investigate the in vivo effects of LAGE3. Then, the protein levels of LAGE3, p-p38, p-38, c-Jun N-terminal kinase (JNK),p-JNK, extracellular signal-regulated kinase (ERK), and p-ERK were detected by western blot.
We found that LAGE3 was upregulated in HCC tissues compared to adjacent tissues, and its high expression was correlated with poor overall survival by bioinformatics analysis. Next, we manually regulated the expression of LAGE3 in HCC cells. The knockdown of LAGE3 inhibited the proliferation of HCC cells by arresting the cell cycle in G1 phase. Also the downregulation of LAGE3 inhibited cell migration and invasion and induced apoptosis of HCC cells, while overexpression of LAGE3 promoted the malignant phenotypes of HCC. These results were further confirmed by the in vivo growth of HCC xenografts and the inhibition of apoptosis of HCC tumor cells. Furthermore, we found that LAGE3 exerted cancer-promoting effects by potentiating the JNK and ERK signaling pathway. An ERK inhibitor (10 μM SCH772984) or JNK inhibitor (25 μM SP600125) repressed the upregulated LAGE3-induced proliferation, migration, and invasion of HCC cells.
LAGE3 enhanced the malignant phenotypes of HCC by promoting the JNK and ERK signaling pathway.
肝细胞癌（HCC）是全球癌症死亡的第二大主要原因，由于其高复发和转移率，缺乏有效的治疗方法。本研究旨在探讨 L 抗原家族成员 3（LAGE3，一种参与正转录的 LAGE 基因家族成员）对 HCC 进展的影响。
通过实时定量聚合酶链反应检测 LAGE3 的表达。采用 3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐、集落形成实验、EdU 和细胞周期分析实验评估 HCC 细胞的增殖。用 Annexin V-FITC/PI 和 TUNEL 实验评估 HCC 细胞的凋亡率。用划痕愈合和 Transwell 实验研究 HCC 细胞的迁移和侵袭。用 2×10 个 Hep3B 或 SK-HEP1 细胞建立 HCC 异种移植模型，以研究 LAGE3 的体内作用。然后，通过 Western blot 检测 LAGE3、p-p38、p38、c-Jun N-末端激酶（JNK）、p-JNK、细胞外信号调节激酶（ERK）和 p-ERK 的蛋白水平。
我们发现 LAGE3 在 HCC 组织中的表达高于相邻组织，通过生物信息学分析，其高表达与总生存期不良相关。接下来，我们手动调节 HCC 细胞中 LAGE3 的表达。LAGE3 的敲低通过将细胞周期阻滞在 G1 期抑制 HCC 细胞的增殖。此外，LAGE3 的下调抑制 HCC 细胞的迁移和侵袭并诱导 HCC 细胞凋亡，而过表达 LAGE3 促进 HCC 的恶性表型。这些结果通过 HCC 异种移植的体内生长和 HCC 肿瘤细胞凋亡的抑制进一步得到证实。此外，我们发现 LAGE3 通过增强 JNK 和 ERK 信号通路发挥致癌作用。ERK 抑制剂（10 μM SCH772984）或 JNK 抑制剂（25 μM SP600125）抑制上调的 LAGE3 诱导的 HCC 细胞增殖、迁移和侵袭。
LAGE3 通过促进 JNK 和 ERK 信号通路增强 HCC 的恶性表型。
