Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, 430060, Hubei, People's Republic of China.
Dig Dis Sci. 2022 Oct;67(10):4780-4796. doi: 10.1007/s10620-021-07335-1. Epub 2022 Jan 7.
KISS-1 is an established tumor suppressor that inhibits metastases in various malignancies. However, little is known regarding its role in esophageal squamous cell carcinoma (ESCC). The aim of the present study was to identify the possible mechanisms of KISS-1 in ESCC metastasis.
The expression levels of KISS-1 mRNA and protein in ESCC samples and cell lines were analyzed by qRT-PCR, IHC, and western blotting. Bisulfite sequencing PCR (BSP) and methylation-specific PCR (MSP) were used to analyze the methylation pattern of KISS-1 promoter in ESCC cells with or without 5-Aza-dC treatment. The role of KISS-1 in the progression and metastasis of ESCC was analyzed through in vitro functional assays.
KISS-1 mRNA and protein were markedly downregulated in ESCC tissues and cell lines compared to the respective controls. Hypermethylation of KISS-1 promoter correlated to its lower expression levels in ESCC, and KISS-1 demethylation inhibited tumor progression. Ectopic KISS-1 overexpression inhibited tumor cell metastasis in vitro. In addition, KISS-1 overexpression downregulated the matrix metalloproteinase 2 and 9 (MMP2 and 9) and inhibited epithelial-mesenchymal transition (EMT). Finally, KISS-1 downregulated phosphorylated extracellular regulated protein kinase 1/2 (ERK1/2) and phosphorylated p38 mitogen-activated protein kinase (MAPK) without affecting their total expression levels in the ESCC cells. MAPK/ERK and p38 MAPK agonists reversed the suppressive effects of KISS-1.
The hypermethylation of KISS-1 promoter partly contributed to its downregulation in ESCC. KISS-1 inhibits the metastasis of ESCC cells by targeting the MMP2/9/ERK/p38 MAPK axis.
KISS-1 是一种已被证实的肿瘤抑制因子，可抑制多种恶性肿瘤的转移。然而，其在食管鳞状细胞癌（ESCC）中的作用知之甚少。本研究旨在确定 KISS-1 在 ESCC 转移中的可能机制。
通过 qRT-PCR、免疫组织化学和 Western blot 分析 ESCC 样本和细胞系中 KISS-1 mRNA 和蛋白的表达水平。采用亚硫酸氢盐测序 PCR（BSP）和甲基化特异性 PCR（MSP）分析经或未经 5-Aza-dC 处理的 ESCC 细胞中 KISS-1 启动子的甲基化模式。通过体外功能测定分析 KISS-1 在 ESCC 进展和转移中的作用。
与相应对照相比，KISS-1 mRNA 和蛋白在 ESCC 组织和细胞系中明显下调。KISS-1 启动子的高甲基化与其在 ESCC 中的低表达水平相关，KISS-1 去甲基化抑制肿瘤进展。异位过表达 KISS-1 可抑制体外肿瘤细胞转移。此外，KISS-1 过表达下调基质金属蛋白酶 2 和 9（MMP2 和 9）并抑制上皮间质转化（EMT）。最后，KISS-1 下调磷酸化细胞外调节蛋白激酶 1/2（ERK1/2）和磷酸化 p38 丝裂原活化蛋白激酶（p38 MAPK），而不影响 ESCC 细胞中它们的总表达水平。MAPK/ERK 和 p38 MAPK 激动剂逆转了 KISS-1 的抑制作用。
KISS-1 启动子的高甲基化部分导致 ESCC 中其下调。KISS-1 通过靶向 MMP2/9/ERK/p38 MAPK 轴抑制 ESCC 细胞的转移。
