Department of Pancreatic Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1277 Jiefang Avenue, Wuhan, 430022, Hubei Province, China.
J Exp Clin Cancer Res. 2021 Apr 8;40(1):124. doi: 10.1186/s13046-021-01894-x.
Pancreatic cancer is a malignant tumor and ranks the sixth in incidence among cancers. Circular RNA (circRNA) has been reported to regulate the progression of pancreatic cancer. However, the effects of circ-membrane bound O-acyltransferase domain containing 2 (circ-MBOAT2) on regulating pancreatic cancer process were unclear.
The expression levels of circ-MBOAT2, microRNA-433-3p (miR-433-3p) and glutamic-oxaloacetic transaminase 1 (GOT1) mRNA were detected by quantitative real-time polymerase chain reaction (qRT-PCR). GOT1 protein expression was determined by western blot analysis. Cell proliferation was illustrated by 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide (MTT) and cell colony formation assay. Cell apoptosis was demonstrated by flow cytometry analysis. Cell invasion and migration were investigated by transwell invasion and wound-healing assays. Glutamine catabolism was explained by detecting glutamine consumption, alpha ketoglutarate (α-KG) production and glutamate production. In vivo assay was performed to illustrate the impacts of circ-MBOAT2 silencing on tumor formation in vivo. The binding relationship between miR-433-3p and circ-MBOAT2 or GOT1 was predicted by circinteractome or starbase online databases, and identified by dual-luciferase reporter assay.
Circ-MBOAT2 and GOT1 expression were significantly upregulated, while miR-433-3p expression was downregulated in pancreatic cancer tissues and cells compared with normal pancreatic tissues or cells. Circ-MBOAT2 silencing repressed cell proliferation, migration, invasion and glutamine catabolism, whereas promoted cell apoptosis in pancreatic cancer. Additionally, circ-MBOAT2 acted as a sponge of miR-433-3p, which was found to be associate with GOT1. MiR-433-3p inhibitors hindered circ-MBOAT2 silencing-mediated impacts on pancreatic cancer progression and glutamine catabolism. Furthermore, circ-MBOAT2 silencing repressed tumor formation in vivo.
Circ-MBOAT2 modulated tumor development and glutamine catabolism by miR-433-3p/GOT1 axis in pancreatic cancer. This finding suggests that circ-MBOAT2 may be a therapeutic target for pancreatic cancer.
胰腺癌是一种恶性肿瘤，在癌症发病率中排名第六。环状 RNA（circRNA）已被报道可调节胰腺癌的进展。然而，circ-膜结合酰基转移酶结构域包含 2（circ-MBOAT2）对调节胰腺癌过程的影响尚不清楚。
通过实时定量聚合酶链反应（qRT-PCR）检测 circ-MBOAT2、微小 RNA-433-3p（miR-433-3p）和谷草转氨酶 1（GOT1）mRNA 的表达水平。通过 Western blot 分析检测 GOT1 蛋白表达。通过 3-(4,5)-二甲基噻唑 (-z-y1)-3,5-二苯基四唑溴盐（MTT）和细胞集落形成实验说明细胞增殖。通过流式细胞术分析说明细胞凋亡。通过 Transwell 侵袭和划痕愈合实验研究细胞侵袭和迁移。通过检测谷氨酰胺消耗、α-酮戊二酸（α-KG）产生和谷氨酸产生来解释谷氨酰胺分解代谢。进行体内实验以说明沉默 circ-MBOAT2 对体内肿瘤形成的影响。通过 circinteractome 或 starbase 在线数据库预测 miR-433-3p 与 circ-MBOAT2 或 GOT1 的结合关系，并通过双荧光素酶报告基因实验进行验证。
与正常胰腺组织或细胞相比，胰腺癌组织和细胞中 circ-MBOAT2 和 GOT1 的表达显著上调，而 miR-433-3p 的表达下调。沉默 circ-MBOAT2 可抑制胰腺癌细胞增殖、迁移、侵袭和谷氨酰胺分解代谢，而促进细胞凋亡。此外，circ-MBOAT2 作为 miR-433-3p 的海绵，与 GOT1 相关。miR-433-3p 抑制剂阻碍了 circ-MBOAT2 沉默对胰腺癌细胞增殖和谷氨酰胺分解代谢的影响。此外，沉默 circ-MBOAT2 可抑制体内肿瘤形成。
circ-MBOAT2 通过 miR-433-3p/GOT1 轴调节胰腺癌的肿瘤发生和谷氨酰胺分解代谢。这一发现表明 circ-MBOAT2 可能是胰腺癌的治疗靶点。
