Conclusion
The combination of FTD/TPI and fruquintinib could be a promising treatment option for colorectal cancer.
Methods
The enhancement of the antitumor effects with FTD/TPI and fruquintinib combination, compared to the single drugs given alone was evaluated using two human colorectal cancer xenografts in nude mouse models. FTD/TPI (200 mg/kg) was orally administered for 5 consecutive days followed by 2 days of rest in a 7-day period. Fruquintinib (10 mg/kg) was orally administered consecutively for 2 and 3 weeks in SW48 and HCT 116 tumor-bearing models, respectively. After treatment with these agents, the microvessel density was evaluated by CD31 immunohistochemical analyses.
Results
In both models, FTD/TPI and fruquintinib significantly inhibited tumor growth, and the activity of the combined treatment was significantly superior to that of either monotherapy. Body weight loss of greater than 20% was not observed in any group. A histochemical analysis showed nuclei enlargement, abnormal mitosis, and karyorrhexis in the FTD/TPI treatment group. The microvessel density in the HCT 116 tumors treated with FTD/TPI and fruquintinib was significantly lower than that in the control group.