Li Guoqing, Wu Qiulei, Gong Lanqing, Xu Xiaohan, Cai Jing, Xu Linjuan, Zeng Ya, He Xiaoqi, Wang Zehua
Department of Obstetrics and Gynecology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
Cancer Cell Int. 2021 Oct 26;21(1):568. doi: 10.1186/s12935-021-02273-4.
Pelvic lymph node metastasis (LNM) is a crucial independent prognostic factor in cervical cancer (CCa) and serves as an indicator for radiation therapy as the primary or an adjuvant treatment option. However, preoperative diagnosis of LNM remains challenging. Thus, we aimed to identify biomarkers of LNM in patients with presumed early-stage CCa.
The differentially expressed genes (DEGs) between tumours with different lymph node statuses were identified by using The Cancer Genome Atlas database. Then, univariate Cox regression analysis and Kaplan-Meier analyses were utilized to screen overall survival (OS)-associated genes. Multivariate Cox analysis and logistical analysis were utilized to evaluate independent risk factors for OS and LNM, respectively. Subsequently, the protein level of fatty acid binding protein 4 (FABP4) was detected in normal cervical and CCa tissues by immunohistochemistry assays. EdU assays were performed to determine whether FABP4 altered the proliferation of cervical cancer cells. Wound healing and Transwell assays were conducted to explore the effects of FABP4 depletion on migratory and invasive abilities of cervical cancer cells. F-actin fluorescence staining were performed to investigate morphological change and Western blotting analyses were performed to determine epithelial mesenchymal transition-related marker expression and downstream signalling pathways.
A total of 243 DEGs, including 55 upregulated and 188 downregulated DEGs, were found in CCa patients with LNM versus those without LNM. Among these, FABP4 was found to be closely associated with poor OS. Multivariate analysis uncovered that FABP4 was an independent risk factor for OS and LNM in patients with CCa. The immunohistochemical results verified dramatically increased FABP4 expression in CCa tissues compared to normal cervical epithelia and its association with poor OS and LNM. In vitro, The proliferation, migration and invasion of cervical cancer cells were significantly inhibited after knocking down of FABP4, which was accompanied by elevated expression of E-cadherin and downregulated expression of N-cadherin, Vimentin and p-AKT.
FABP4 might be a promising biomarker of LNM and survival in patients with early-stage CCa and therefore could significantly contribute to the development of personalized prognosis prediction and therapy optimization.
盆腔淋巴结转移（LNM）是宫颈癌（CCa）的一个关键独立预后因素，也是放射治疗作为主要或辅助治疗选择的一个指标。然而，LNM的术前诊断仍然具有挑战性。因此，我们旨在确定疑似早期CCa患者中LNM的生物标志物。
利用癌症基因组图谱数据库确定不同淋巴结状态肿瘤之间的差异表达基因（DEGs）。然后，采用单变量Cox回归分析和Kaplan-Meier分析来筛选总生存（OS）相关基因。多变量Cox分析和逻辑分析分别用于评估OS和LNM的独立危险因素。随后，通过免疫组织化学检测法检测正常宫颈组织和CCa组织中脂肪酸结合蛋白4（FABP4）的蛋白水平。进行EdU检测以确定FABP4是否改变宫颈癌细胞的增殖。进行伤口愈合和Transwell检测以探讨FABP4缺失对宫颈癌细胞迁移和侵袭能力的影响。进行F-肌动蛋白荧光染色以研究形态变化，并进行蛋白质印迹分析以确定上皮-间质转化相关标志物的表达和下游信号通路。
在有LNM的CCa患者与无LNM的患者中，共发现243个DEGs，包括55个上调和188个下调的DEGs。其中，发现FABP4与不良OS密切相关。多变量分析发现FABP4是CCa患者OS和LNM的独立危险因素。免疫组织化学结果证实，与正常宫颈上皮相比，CCa组织中FABP4表达显著增加，且其与不良OS和LNM相关。在体外，敲低FABP4后，宫颈癌细胞的增殖、迁移和侵袭显著受到抑制，同时伴有E-钙黏蛋白表达升高以及N-钙黏蛋白、波形蛋白和磷酸化AKT表达下调。
FABP4可能是早期CCa患者LNM和生存的一个有前景的生物标志物，因此可能对个性化预后预测和治疗优化的发展做出重大贡献。
