Oral-recombinant Methioninase Converts an Osteosarcoma from Docetaxel-resistant to -Sensitive in a Clinically-relevant Patient-derived Orthotopic-xenograft (PDOX) Mouse Model

Background/Aim: Osteosarcoma is the most frequent malignant bone tumor. Failure of first-line therapy results in poor prognosis osteosarcoma. In present report, we examined efficacy combination oral recombinant methioninase (o-rMETase) and docetaxel (DOC) on an osteosarcoma patient-derived orthotopic xenograft (PDOX) mouse model. Materials Methods: Osteosarcoma-PDOX models were established by tumor insertion within tibia nude mice. The PDOX randomized into four groups (4-5 mice per group): control; o-rMETae alone; DOC o- rMETase combined with DOC. treatment period was 3 weeks. Results: o-rMETase showed significant compared to control group (p=0.03). contrast, there no alone or (p=0.65, 0.60, respectively). Conclusion: converted from DOC-resistant -sensitive. This may be effective against recalcitrant other cancers.