Supplemental Material and Methods, Table 1, and Figures 1-7 from Systematic Screening Identifies Dual PI3K and mTOR Inhibition as a Conserved Therapeutic Vulnerability in Osteosarcoma

Gupte, Ankita; Baker, Emma K.; Wan, Soo-San; Stewart, Elizabeth; Loh, Amos; Shelat, Anang A.; Gould, Cathryn M.; Chalk, Alistair M.; Taylor, Scott; Lackovic, Kurt; Karlström, Åsa; Mutsaers, Anthony J.; Desai, Jayesh; Madhamshettiwar, Piyush B.; Zannettino, Andrew C.W.; Burns, Chris; Huang, David C.S.; Dyer, Michael A.; Simpson, Kaylene J.; Walkley, Carl R.

doi:10.1158/1078-0432.22458170.v1

Supplemental Material and Methods, Table 1, and Figures 1-7 from Systematic Screening Identifies Dual PI3K and mTOR Inhibition as a Conserved Therapeutic Vulnerability in Osteosarcoma

journal contribution

posted on 2023-03-31, 18:41 authored by Ankita Gupte, Emma K. Baker, Soo-San Wan, Elizabeth Stewart, Amos Loh, Anang A. Shelat, Cathryn M. Gould, Alistair M. Chalk, Scott Taylor, Kurt Lackovic, Åsa Karlström, Anthony J. Mutsaers, Jayesh Desai, Piyush B. Madhamshettiwar, Andrew C.W. Zannettino, Chris Burns, David C.S. Huang, Michael A. Dyer, Kaylene J. Simpson, Carl R. Walkley

Supplemental Material and Methods, Table 1, and Figures 1-7. Supplemental Table 1 - Primer Sequences used for qPCR. Supplemental Figure 1 - Suppressors of doxorubicin induced cell death from siRNA screen. Supplemental Figure 2 - Response to Spliceostatin A treatment. Supplemental Figure 3 - Dose response of curves of murine and human OS cells to dual PI3K/mTOR inhibitors. Supplemental Figure 4 - siRNA against PI3K subunits and mTOR complex components Supplemental Figure 5 - BYL719 and Everolimus Synergy Matrix Supplemental Figure 6 - BYL719 and Everolimus treatment of primary murine osteoblasts. Supplemental Figure 7. GSK2126458 treatment reduces OS tumour proliferation in vivo.

History

ARTICLE ABSTRACT

Purpose: Osteosarcoma is the most common cancer of bone occurring mostly in teenagers. Despite rapid advances in our knowledge of the genetics and cell biology of osteosarcoma, significant improvements in patient survival have not been observed. The identification of effective therapeutics has been largely empirically based. The identification of new therapies and therapeutic targets are urgently needed to enable improved outcomes for osteosarcoma patients.Experimental Design: We have used genetically engineered murine models of human osteosarcoma in a systematic, genome-wide screen to identify new candidate therapeutic targets. We performed a genome-wide siRNA screen, with or without doxorubicin. In parallel, a screen of therapeutically relevant small molecules was conducted on primary murine– and primary human osteosarcoma–derived cell cultures. All results were validated across independent cell cultures and across human and mouse osteosarcoma.Results: The results from the genetic and chemical screens significantly overlapped, with a profound enrichment of pathways regulated by PI3K and mTOR pathways. Drugs that concurrently target both PI3K and mTOR were effective at inducing apoptosis in primary osteosarcoma cell cultures in vitro in both human and mouse osteosarcoma, whereas specific PI3K or mTOR inhibitors were not effective. The results were confirmed with siRNA and small molecule approaches. Rationale combinations of specific PI3K and mTOR inhibitors could recapitulate the effect on osteosarcoma cell cultures.Conclusions: The approaches described here have identified dual inhibition of the PI3K–mTOR pathway as a sensitive, druggable target in osteosarcoma, and provide rationale for translational studies with these agents. Clin Cancer Res; 21(14); 3216–29. ©2015 AACR.