Combination of Trabectedin With Irinotecan, Leucovorin and 5-Fluorouracil Arrests Primary Colorectal Cancer in an Imageable Patient-derived Orthotopic Xenograft Mouse Model

Background/Aim: The aim of the present study was to determine the efficacy of trabectedin combined with FOLFIRI (irinotecan, leucovorin and 5-fluorouracil) on a colorectal cancer (CRC) patient-derived orthotopic xenograft (iPDOX) mouse model. Materials and Methods: A CRC tumor from a patient previously established in nude mice was implanted subcutaneously in transgenic green fluorescence protein (GFP)-expressing nude mice in order to label the tumor stromal cells with GFP. Mice were randomized into four groups: Group 1, untreated control; group 2, FOLFIRI; group 3, trabectedin alone; group 4, trabectedin plus FOLFIRI. Tumor width, length, and mouse body weight was measured twice every week. Results: All three treatment groups showed inhibited tumor growth compared to the untreated control group. Only the combination of FOLFIRI and trabectedin arrested tumor growth. No significant changes was observed in body weight in any group. Conclusion: These findings suggest that the combination of trabectedin plus FOLFIRI has clinical potential for patients with CRC.