Because short hairpin knockdowns (KD) of QSOX1 have been shown to suppress tumor growth and invasion <i>in vitro</i> and <i>in vivo</i>, we hypothesized that chemical compounds inhibiting QSOX1 enzymatic activity would also suppress tumor growth, invasion, and metastasis.
High QSOX1 expression correlates with tumor invasiveness and Gleason grade, reflects aggressive tumor features, and could be an important biomarker and therapeutic target.
In a nude mouse-human tumor xenograft model, tumors containing shRNA for QSOX1 grew significantly more slowly than controls, suggesting that QSOX1 supports a proliferative phenotype in vivo.
In addition, Kaplan Meyer analyses revealed QSOX1 RNA as a highly significant predictive marker for both relapse and poor overall survival in Luminal B tumors.
Moreover, we investigated QSOX1's potential role in regulating tumor growth and metastasis using cellular models in which we overexpressed or extinguished QSOX1 and xenograft experiments.