Zhang Wenfan, Zhao Jing, Fan Xueting, Chen Shuang, Wang Rong
Department of Laboratory Medicine, School of Medical Technology, Tianjin Medical University, Tianjin, China.
Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin, China.
Cell Death Dis. 2025 Apr 21;16(1):324. doi: 10.1038/s41419-025-07512-4.
Aberrant methylation of the EphA7 promoter has been observed in cervical cancer (CC); however, its precise function and role in CC remain largely unknown. In this study, we investigated the role and molecular mechanisms of EphA7 promoter methylation in cervical carcinogenesis. First, our results indicated that the reactivation of EphA7 expression via a CRISPR demethylation tool (dCas9-Tet1) had antitumor effects. It restrained tumor proliferation and invasion while promoting apoptosis via the PI3K/AKT signaling pathway in both CaSki and SiHa cells. The upstream interacting factors were subsequently captured by CRISPR-mediated pull-down in situ, and the result revealed that SP1 and MAZ interacted with the promoter of EphA7. However, the perturbation results revealed that EphA7 expression was associated with SP1/DNMT1 but not MAZ. Furthermore, 17-β-estradiol (E2) can upregulate EphA7 expression through demethylation via the SP1/DNMT1 axis. A rescue experiment revealed that interference with SP1 expression could restore the effect of E2 on increasing the expression of EphA7 by upregulating estrogen receptor expression. In addition, EphA7 demethylation reduced the half-maximal inhibitory concentration (IC) of cisplatin and paclitaxel. Pooled analysis revealed that EphA7 promoter hypermethylation was positively correlated with tumor purity but negatively correlated with immune cell infiltration, cytotoxic T lymphocyte (CTL) and immune checkpoint (IC) activity, and the expression of EphA7 was significantly positively correlated with tumor mutational burden (TMB), microsatellite instability (MSI) and the presence of single nucleotide variant (SNV) neoantigens, suggesting a better prognosis for patients with EphA7 promoter hypomethylation and high expression. Collectively, these findings indicate that targeted demethylation of the EphA7 promoter and restoration of endogenous EphA7 expression by dCas9-Tet1 are promising therapeutic approaches and are favorable for the prognosis of CC patients.
在宫颈癌(CC)中已观察到EphA7启动子的异常甲基化;然而,其在CC中的精确功能和作用在很大程度上仍不清楚。在本研究中,我们调查了EphA7启动子甲基化在宫颈癌发生中的作用和分子机制。首先,我们的结果表明,通过CRISPR去甲基化工具(dCas9-Tet1)重新激活EphA7表达具有抗肿瘤作用。它通过PI3K/AKT信号通路抑制CaSki和SiHa细胞中的肿瘤增殖和侵袭,同时促进细胞凋亡。随后通过CRISPR介导的原位下拉捕获上游相互作用因子,结果显示SP1和MAZ与EphA7启动子相互作用。然而干扰实验结果表明,EphA7表达与SP1/DNMT1相关,而与MAZ无关。此外,17-β-雌二醇(E2)可通过SP1/DNMT1轴去甲基化上调EphA7表达。一项挽救实验表明,干扰SP1表达可通过上调雌激素受体表达恢复E2对增加EphA7表达的作用。此外,EphA7去甲基化降低了顺铂和紫杉醇的半数抑制浓度(IC)。汇总分析显示,EphA7启动子高甲基化与肿瘤纯度呈正相关,但与免疫细胞浸润、细胞毒性T淋巴细胞(CTL)和免疫检查点(IC)活性呈负相关,并且EphA7的表达与肿瘤突变负荷(TMB)、微卫星不稳定性(MSI)和单核苷酸变异(SNV)新抗原的存在显著正相关,这表明EphA7启动子低甲基化和高表达的患者预后较好。总的来说,这些发现表明,EphA7启动子的靶向去甲基化和通过dCas9-Tet1恢复内源性EphA7表达是有前景的治疗方法,并且有利于CC患者的预后。