Background and aims: Colorectal cancer (CRC) is known as the fourth leading cause of death across the world. The fate of patients depends on the metastatic spread of cancer cells. Micrometastases are small clusters of cancer cells with no diagnostic evidence during diagnosis and surgery. Therefore, experimental models for micrometastasis are necessary to investigate tumors. We developed a mouse model to evaluate micrometastasis of colon carcinoma cells by systemic injection of tumor cells.
Methods: In this study, stably transfected CT26 cells expressing Leishmania major GP63 were intravenously (IV) injected into BALB/c mice for induction of micrometastases. The mice were divided into three groups and the groups were sacrificed on days 3, 7, and 14 of the injection. reverse transcriptase-polymerase chain reaction (RT-PCR) was performed on tissue samples to detect Gp63 gene.
Results: Our results showed the successful construction and transfection of pcDNA3 L. major Gp63 into CT26 cells. After IV injection, total cellular RNA was extracted and the Gp63 gene was detected in the liver, lung, and kidney but not in the colon.
Conclusion: Due to the significance of micrometastasis and the need to establish simple models for cancer research, an experimental mouse model was developed. CT26 tumor cells stably expressing Gp63 generated a potent system for diagnosis of micrometastatic cells in tissues. Injection into the tail vein is a practical model for cancer research because of the lower fatality rate and no need for anesthesia