Background and Aim: Heat shock protein 90 (HSP90) and mammalian target of rapamycin (mTOR) are
involved in the molecular pathogenesis of advanced oral squamous cell carcinoma. HSP90 inhibitors are capable of
effectively interfering with multiple signaling pathways, including the mTOR signaling pathway. However, the combined
effects of HSP90 and mTOR inhibitors on oral squamous cell carcinoma are still unknown. In this study, we investigated
the dual treatment of the novel HSP90 inhibitor NVP-AUY922 and temsirolimus against oral squamous cell carcinoma.
Materials and Methods: The effect of the combination of NVP-AUY922 and temsirolimus on oral squamous cell
carcinoma in vitro and in vivo was determined by MTS assay and mouse xenograft models. The effect of the combination
on angiogenesis was determined by tube formation assay and angioreactor.
Results: The combination treatment of NVP-AUY922 and temsirolimus significantly inhibited the proliferation of SAS
oral squamous cell carcinoma cells in vitro and suppressed the growth of oral squamous cell carcinoma xenografts in vivo.
We have clearly shown that the combination treatment of NVP-AUY922 and temsirolimus inhibited vascular formation
both in vitro and in vivo. Moreover, the combination treatment of NVP-AUY922 and temsirolimus prolonged the survival
rate in mice xenografted with oral squamous cell carcinoma.
Conclusions: Here, we showed the activity of a combination of mTOR and HSP90 inhibitors for the treatment of
advanced oral squamous carcinoma.