TY - JOUR T1 - Combination Treatment With Sorafenib and Everolimus Regresses a Doxorubicin-resistant Osteosarcoma in a PDOX Mouse Model JF - Anticancer Research JO - Anticancer Res SP - 4781 LP - 4786 DO - 10.21873/anticanres.13662 VL - 39 IS - 9 AU - TAKASHI HIGUCHI AU - NORIHIKO SUGISAWA AU - KENTARO MIYAKE AU - HIROMICHI OSHIRO AU - NORIO YAMAMOTO AU - KATSUHIRO HAYASHI AU - HIROAKI KIMURA AU - SHINJI MIWA AU - KENTARO IGARASHI AU - ZOEY KLINE AU - PAIGE BELT AU - SANT P. CHAWLA AU - MICHAEL BOUVET AU - SHREE RAM SINGH AU - HIROYUKI TSUCHIYA AU - ROBERT M. HOFFMAN Y1 - 2019/09/01 UR - http://ar.iiarjournals.org/content/39/9/4781.abstract N2 - Background/Aim: Osteosarcoma is a rare but recalcitrant type of bone cancer. To discover an effective therapy for osteosarcoma, we used a patient-derived orthotopic xenograft (PDOX) mouse model. A PDOX mouse model has been established for all major cancer types. Strong synergistic efficacy of sorafenib (SFN) and everolimus (EVL) has been demonstrated in several cancers. In the present study, we examined the efficacy of a SFN and EVL combination on a doxorubicin (DOX)-resistant osteosarcoma PDOX. Materials and Methods: The osteosarcoma PDOX models were randomly divided into five treatment groups, each containing six mice: Control; DOX; SFN; EVL; and a combination of SFN and EVL. Mice were treated for 14 days. To observe the efficacy of these treatments, tumor size and body weight were measured, and histological sections were analyzed. Results: Tumor growth regression was observed only in the mice treated with the combination of SFN-EVL. Histological analysis revealed necrosis with degenerative changes in tumors treated with a combination of SFN-EVL. Conclusion: A SFN-EVL combination could be a novel effective treatment option for osteosarcoma. ER -