a Department of Hepatobiliary Surgery, People Hospital of LiShui, The Sixth Affiliated Hospital of Wenzhou Medical University , The First Affiliated Hospital of LiShui University , LiShui , Zhejiang , PR China.
Cancer Biol Ther. 2019;20(5):711-719. doi: 10.1080/15384047.2018.1564558. Epub 2019 Feb 12.
Hepatocellular carcinoma (HCC), the most common aggressive malignancy of liver, is the third leading cause of cancer death across the world. Laminin gamma 1 (Lamc1), encodes laminin-γ1, an extracellular matrix protein involved in various progresses such as tumor cell proliferation and metabolism. In the present study, high expression of Lamc1 and PKM2 was observed in tumor tissues of HCC patients. In vitro, down-regulation of Lamc1 inhibited proliferation of HCC cells by promoting cell death, reduced glucose consumption and lactate production, accompanied by a decrease in the expression of glucose transporter 1 (GLUT1) and lactate dehydrogenase A (LDHA), and PTEN increased, as well as PTEN S380 and AKT S473/T308 phosphorylation decreased, while Lamc1 up-regulation had the opposite effect. The effects of PKM2 were similar to that of Lamc1 and markedly counteracted the effects of Lamc1 down-regulation. In addition, Lamc1-induced increase in PKM2 expression was strongly attenuated by a PI3K inhibitor, LY294002 or a si-p110 PI3K, with a significant decrease in GLUT1 and LDHA expression, as well as decreased AKT T308 phosphorylation. Thus, we speculated that Lamc1 was implicated in the progression of HCC probably by regulating PKM2 expression through PTEN/AKT pathway.
肝细胞癌(HCC)是肝脏最常见的侵袭性恶性肿瘤,是全球癌症死亡的第三大主要原因。层粘连蛋白γ 1(Lamc1)编码层粘连蛋白-γ1,一种细胞外基质蛋白,参与肿瘤细胞增殖和代谢等多种进展。在本研究中,观察到 HCC 患者肿瘤组织中 Lamc1 和 PKM2 的高表达。在体外,下调 Lamc1 通过促进细胞死亡抑制 HCC 细胞的增殖,减少葡萄糖消耗和乳酸生成,伴随着葡萄糖转运蛋白 1(GLUT1)和乳酸脱氢酶 A(LDHA)的表达减少,以及 PTEN 增加,同时 PTEN S380 和 AKT S473/T308 磷酸化减少,而上调 Lamc1 则产生相反的效果。PKM2 的作用与 Lamc1 相似,明显抵消了 Lamc1 下调的作用。此外,PI3K 抑制剂 LY294002 或 si-p110 PI3K 强烈减弱了 Lamc1 诱导的 PKM2 表达增加,导致 GLUT1 和 LDHA 表达减少,以及 AKT T308 磷酸化减少。因此,我们推测 Lamc1 可能通过 PTEN/AKT 途径调节 PKM2 表达参与 HCC 的进展。