- 作者: Hong-Yi Chang, Hsin-Mei Chang, Tsung-Jung Wu, Chang-Yao Chaing, Tzong-Shin Tzai, Hong-Lin Cheng, Giri Raghavaraju, Nan-Haw Chow and Hsiao-Sheng Liu
- 作者服務機構: 1. Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan, Republic of China
- 中文摘要:
- 英文摘要:
Background
Lutheran/basal cell adhesion molecule (Lu/BCAM) is a membrane bound glycoprotein. This study was performed to investigate the role and downstream signaling pathway of Lu/BCAM in human bladder tumorigenesis.
Methods
Five human bladder cancer (E6, RT4, TSGH8301, TCCSUP and J82), one stable mouse fibroblast cell line (NIH-Lu) expressing Lu/BCAM transgene and sixty human uroepithelial carcinoma specimens were analyzed by real-time PCR, immunohistochemistry (IHC), immunofluorescence (IFA) staining, Western blotting and promoter luciferase assay for Lu/BCAM, respectively. The tumorigenicity of Lu/BCAM was demonstrated by focus formation, colony-forming ability, tumour formation, cell adhesion and migration.
Results
H-ras V12 was revealed to up-regulate Lu/BCAM at both transcriptional and translation levels. Lu/BCAM expression was detected on the membrane of primary human bladder cancer cells. Over-expression of Lu/BCAM in NIH-Lu stable cells increased focus number, colony formation and cell adhesion accompanied with F-actin rearrangement and decreased cell migration compared with parental NIH3T3 fibroblasts. In the presence of laminin ligand, Lu/BCAM overexpression further suppressed cell migration accompanied with increased cell adhesion. We further revealed that laminin-Lu/BCAM-induced cell adhesion and F-actin rearrangement were through increased Erk phosphorylation with an increase of RhoA and a decrease of Rac1 activity. Similarly, high Lu/BCAM expression was detected in the tumors of human renal pelvis, ureter and bladder, and was significantly associated with advanced tumor stage (p = 0.02). Patients with high Lu/BCAM expression showed a trend toward larger tumor size (p = 0.07) and lower disease-specific survival (p = 0.08), although not reaching statistical significance.
Conclusion
This is the first report showing that Lu/BCAM, in the presence of its ligand laminin, is oncogenic in human urothelial cancers and may have potential as a novel therapeutic target. - 中文關鍵字:
- 英文關鍵字: Lutheran, Basal cell adhesion molecule, Laminin, Urothelial cancer, Ras