An improved orthotopic rat bladder tumor model using Dil-loaded fluorescent AY-27 cells

Area of Science:

• Oncology
• Biomedical Engineering
• Drug Development

Background:

• Orthotopic rat bladder tumor models are crucial for evaluating novel cancer therapeutics.
• Accurate validation of tumor cell inoculation and monitoring tumor progression are essential for reliable preclinical studies.

Purpose of the Study:

• To evaluate an improved orthotopic rat bladder tumor model using fluorescently labeled AY-27 cells.
• To validate the use of fluorescent labeling for visualizing and tracking tumor cell inoculation and growth.
• To assess the therapeutic potential of MM-C treatment in this validated model.

Main Methods:

• AY-27 bladder tumor cells were labeled with 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine (DiI), a fluorescent dye.
• The effect of DiI labeling on AY-27 cell proliferation was assessed in vitro.
• The orthotopic bladder tumor model was used to evaluate the antitumoral effect of intravesical MM-C instillation.

Main Results:

• DiI labeling did not affect AY-27 cell proliferation and remained associated with the cells.
• Fluorescent labeling enabled visualization and validation of tumor cell inoculation, allowing tracking for up to 5 days.
• The AY-27 tumor model showed that malignant tissue formed non-muscle invasive tumors for 1-3 days post-implantation.
• MM-C treatment resulted in complete survival of rats, urothelial restoration by 10-30 days post-treatment, and presence of fluorescent dots indicating immune cell activity.

Conclusions:

• The DiI-labeled AY-27 orthotopic rat bladder tumor model is a validated tool for preclinical cancer therapeutic evaluation.
• This model allows for accurate monitoring of tumor cell behavior and treatment efficacy.
• MM-C demonstrated significant therapeutic potential, leading to tumor regression and tissue regeneration.