Altered growth properties and cell surface changes in ras transformed mouse bladder epithelium

Area of Science:

• Oncology
• Molecular Biology
• Cell Biology

Background:

• The c-Ha-ras-1 oncogene plays a critical role in cell proliferation and differentiation.
• Oncogene activation is a key event in the development of various cancers, including bladder cancer.

Purpose of the Study:

• To investigate the effects of c-Ha-ras-1 oncogene transfection on mouse bladder epithelial cells.
• To identify and characterize novel proteins associated with activated ras oncogenes in urothelial cells.

Main Methods:

• Transfection of mouse bladder epithelial cell lines with the c-Ha-ras-1 oncogene.
• Tumorigenicity and anchorage-independent growth assays.
• Immunoprecipitation and immunofluorescence studies to detect and localize specific proteins.

Main Results:

• Transfection led to tumorigenic potential and anchorage-independent growth in most cell lines.
• An 18 kDa protein, specific to urothelial cells expressing activated ras, was identified.
• This 18 kDa protein was localized to the cell surface and not detected in cells transfected with other oncogenes (polyoma middle T, v-myc).

Conclusions:

• Activated c-Ha-ras-1 oncogene confers tumorigenic properties to mouse bladder epithelial cells.
• A novel, urothelium-specific 18 kDa cell surface protein is associated with activated ras gene expression.
• This protein may serve as a biomarker for ras-driven urothelial carcinogenesis.