1,3,5-triazines inhibit osteosarcoma and avert lung metastasis in a patient-derived orthotopic xenograft mouse model with favorable pharmacokinetics

Iran J Basic Med Sci. 2022 Mar;25(3):295-301. doi: 10.22038/IJBMS.2022.62705.13873.

Abstract

Objectives: Osteosarcoma is a major solid malignant tumor of bone, possessing significant burden on healthcare due to non-availability of specific anticancer agents. The current study was conducted to identify novel 1,3,5-triazine derivatives against osteosarcoma.

Materials and methods: The compounds were synthesized in a straight-forward two-step reaction and subsequently tested against PI3K and mTOR kinase and anticancer activity against osteosarcoma cells (MG-63, U2-OS, and Saos-2). The effect of the most potent compound was evaluated on apoptosis and cell phase of Saos-2 cells. The pharmacological activity was further established in the patient-derived orthotopic xenograft (PDOX) mouse model.

Results: The developed compounds 8 (a-f) showed significant inhibitory activities against PI3K, mTOR, and OS cells. Among the tested series, compound 8a showed highly potent PI3K/mTOR inhibitory activity with significant anticancer activity against Saos-2 cells compared with Imatinib as standard. It also induces apoptosis and causes G2/M arrest in Saos-2 cells. Compound 8a significantly improved body weight, reduced tumor volume, and inhibited lung metastasis in athymic nude mice in a PDOX mouse model. It also showed optimal pharmacokinetic parameters in SD rats.

Conclusion: In summary, 1,3,5-triazine analogs were identified as new PI3K/mTOR inhibitors against osteosarcoma.

Keywords: 1; 3; 5-triazine; Apoptosis; Osteosarcoma; PI3K; mTOR.