目的：探讨肽基精氨酸脱亚胺酶1（PADI1）对肾透明细胞癌（ccRCC）细胞迁移、增殖、侵袭等生物学行为的影响及相关分子机制。方法：首先，利用转录组测序筛选肾癌组织与癌旁组织之间的差异表达基因，并通过GEPIA、TIMER2.0等数据库分析其差异表达水平。选取2024至2025年河北医科大学第四医院泌尿外科术中留存的59例ccRCC患者的组织标本，用RT-qPCR法、免疫组化SP法检测肾癌组织及癌旁组织中PADI1的表达水平，分析其与各临床参数之间的关系。通过划痕愈合、CCK-8、克隆形成及Transwell实验评估PADI1对ccRCC细胞迁移、增殖和侵袭能力的影响，用流式细胞术检测PADI1对细胞周期的影响，并采用WB法检测A498细胞转染si-PADI1后角质化包膜（CE）形成通路及EMT相关蛋白表达的变化。结果：在ccRCC组织中PADI1的相对表达量显著高于癌旁正常组织（P < 0.01），并与患者年龄、淋巴结转移、远处转移及临床分期相关（P < 0.05）。A498和ACHN细胞中转染si-PADI1，可以有效地下调PADI1 mRNA和蛋白表达水平（P < 0.05）；而转染过表达质粒则能够显著上调其表达（P < 0.05），敲低PADI1能够显著抑制其迁移（P < 0.05）、增殖（P < 0.05）与侵袭能力（P < 0.001），而过表达则增强其迁移（P < 0.05）、增殖（P < 0.05）与侵袭能力（P < 0.001），但对细胞周期影响不显著。在A498细胞中，WB实验结果显示PADI1表达能够改变EMT及CE通路相关蛋白表达水平。结论：PADI1在ccRCC中高表达且与ccRCC患者年龄及其淋巴结转移、远处转移、临床分期有关联，其表达水平升高能够影响CE形成通路及加速EMT进程，并增强ccRCC细胞的迁移、增殖、侵袭能力。

Objective: This study aimed to investigate the impact of peptidylarginine deiminase 1 (PADI1) on the migration, proliferation, and invasion of clear cell renal cell carcinoma (ccRCC) cells and the related molecular mechanisms. Methods: Differentially expressed genes between ccRCC and adjacent normal tissues were screened using transcriptome sequencing, and their expression levels were analyzed via GEPIA, TIMER2.0, and other bioinformatics platforms. A total of 59 ccRCC specimens were obtained from patients who underwent nephrectomy at the Department of Urology, The Fourth Hospital of Hebei Medical University between 2024 and 2025. The expression levels of PADI1 in cancerous and adjacent tissues were measured by RT-qPCR and immunohistochemistry (SP method), and their correlations with various clinicopathological parameters were analyzed. The effects of PADI1 on migration, proliferation, and invasion of ccRCC cells were evaluated by wound-healing, CCK-8, colony formation, and Transwell assays. Flow cytometry was used to examine the effects of PADI1 on cell cycle, and Western blotting was employed to detect changes in the expression levels of proteins related to the cornified envelope (CE) formation pathway and epithelial-mesenchymal transition (EMT) in the transfected A498 cells. Results: The relative expression level of PADI1 in ccRCC tissues was significantly higher than that in adjacent normal tissues (P < 0.01), and was correlated with patient age, lymph node metastasis, distant metastasis, and clinical stage (P < 0.05). Transfection of A498 and ACHN cells with si-PADI1 effectively down-regulated PADI1 mRNA and protein expression (P < 0.05), whereas transfection with overexpression plasmid significantly up-regulated its expression (P < 0.05). Knockdown of PADI1 significantly inhibited cell migration (P < 0.05), proliferation (P < 0.05), and invasion (P < 0.001), while PADI1 overexpression enhanced these abilities (P < 0.05, P < 0.05, and P < 0.001), whereas no significant effect on cell cycle progression was detected. Western blotting results showed that altered PADI1 expression in A498 cells was accompanied by changes in the expression levels of proteins related to EMT and the CE formation pathway. Conclusion: PADI1 is highly expressed in ccRCC and associated with patient age, lymph node metastasis, distant metastasis, and clinical stage. Elevated PADI1 expression affects the CE formation pathway and accelerates EMT progression, thereby enhancing the migration, proliferation, and invasion of renal cancer cells.

河北省财政厅政府资助临床医学优秀人才项目（ZF2026205）