Department of Chemical Engineering and Institute of Biotechnology and Chemical Engineering, I-Shou University, Kaohsiung, Taiwan, R.O.C.
Department of Urology, E-Da Cancer Hospital, Kaohsiung, Taiwan, R.O.C.
Anticancer Res. 2023 Apr;43(4):1521-1531. doi: 10.21873/anticanres.16301.
BACKGROUND/AIM: Nuclear respiratory factor 1 (NRF1) is a key mediator of genes involved in mitochondrial biogenesis and the respiratory chain; however, its role in bladder cancer remains unknown. Transitional cell carcinoma, also known as urothelial cell carcinoma, is the most common type of bladder cancer resistant to chemotherapy. An established high-grade and invasive transitional cell carcinoma line from patients with urinary bladder cancer, known as T24, has been extensively used in cancer research. In this study, we aimed to investigate the mechanisms through which NRF1 regulates proliferation and cell migration of bladder cancer cells using the T24 cell line.
Cells were transfected with plasmid cloning DNA for NRF1 to evaluate the effect of NRF1 overexpression on bladder cancer cells. Western blot was used to examine epithelial and mesenchymal markers (E-cadherin and α-smooth muscle actin), transcriptional regulators for epithelial-mesenchymal transition (snail family transcriptional repressors), components of transforming growth factor-β1/SMADs signaling, high-mobility group box 1 (HMGB1), and receptor for advanced glycation end-products (RAGE). The in situ expression of E-cadherin, α-smooth muscle actin and SMAD7 was determined using immunofluorescence staining. Cell migration capacity was assessed by wound-healing assay.
Transfection with NRF1 expression vector repressed the migration capacity of bladder cancer cells, diminishing HMGB1/RAGE expression and reducing transforming growth factor β-associated epithelial-mesenchymal transition in T24 cells.
Therapeutic avenues that increase NRF1 expression may serve as an adjunct to conventional treatments for bladder cancer.
背景/目的：核呼吸因子 1（NRF1）是参与线粒体生物发生和呼吸链的基因的关键介质；然而，其在膀胱癌中的作用尚不清楚。移行细胞癌，也称为尿路上皮细胞癌，是对化疗耐药的最常见膀胱癌类型。一种已建立的来自膀胱癌患者的高级别和侵袭性移行细胞癌系，称为 T24，已广泛用于癌症研究。在这项研究中，我们旨在使用 T24 细胞系研究 NRF1 调节膀胱癌细胞增殖和细胞迁移的机制。
用质粒克隆 DNA 转染细胞，以评估 NRF1 过表达对膀胱癌细胞的影响。使用 Western blot 检测上皮和间充质标志物（E-钙黏蛋白和α-平滑肌肌动蛋白）、上皮-间充质转化的转录调节剂（snail 家族转录阻遏物）、转化生长因子-β1/SMADs 信号通路的组成部分、高迁移率族 box 1（HMGB1）和晚期糖基化终产物受体（RAGE）。使用免疫荧光染色法测定 E-钙黏蛋白、α-平滑肌肌动蛋白和 SMAD7 的原位表达。通过划痕愈合试验评估细胞迁移能力。
转染 NRF1 表达载体抑制了膀胱癌细胞的迁移能力，降低了 HMGB1/RAGE 的表达，并减少了 T24 细胞中转化生长因子β相关的上皮-间充质转化。
增加 NRF1 表达的治疗途径可能作为膀胱癌常规治疗的辅助手段。
