Doxycycline directly targets PAR1 to suppress tumor progression

Abstract

Doxycycline have been reported to exert anti-cancer activity and have been assessed as anti-cancer agents in clinical trials. However, the direct targets of doxycycline in cancer cells remain unclear. In this study, we used a chemical proteomics approach to identify the Protease-activated receptor 1 (PAR1) as a specific target of inhibition of doxycycline. Binding assays and single-molecule imaging assays were performed to confirm the inhibition of doxycycline to PAR1. The effect of doxycycline on multi-omics and cell functions were assessed based on a PAR1/thrombin model. Molecular docking and molecular dynamic simulations revealed that doxycycline interacts with key amino acids in PAR1. Mutation of PAR1 further confirmed the computation-based results. Moreover, doxycycline provides highly selective inhibition of PAR1 signaling in tumors in vitro and in vivo. Using pathological clinical samples co-stained for doxycycline and PAR1, it was found that doxycycline fluorescence intensity and PAR1 expression shown a clear positive correlation. Thus, doxycycline may be a useful targeted anti-cancer drug that should be further investigated in clinical trials.

PAR1 signaling on tumor cells limits tumor growth by maintaining a mesenchymal phenotype in pancreatic cancer

“…Furthermore, it has recently been reported that the epithelial status and E-cadherin expression levels mediate cell proliferation in vitro and promotes xenograft growth in vivo [ 35 , 36 ]. The mechanistic link between PAR1 and E-cadherin has been demonstrated in a follow up study where doxycycline was proposed as a novel PAR1 inhibitor and doxycycline treated cells exhibited increased E-cadherin expression and a significantly decreased metastatic potential [ 37 , 38 ]. Considering these findings we might bring an additional explanation for the increased proliferation in shPAR1 tumors in vivo .…”

Glycyrrhizic Acid-Induced Differentiation Repressed Stemness in Hepatocellular Carcinoma by Targeting c-Jun N-Terminal Kinase 1

“…The terminal alkyne-containing GAyne probe was synthetized by linking GA to 2-(3-but-3-ynyl-3H-diazirin-3-yl)-ethanol. The fluorescent group rhodamine-N3 was synthesized in accordance with previously published procedures (25).…”

The Role of PAR1 Autoantibodies in Patients with Primary Epithelial Ovarian Cancer

“…Nevertheless, there is evidence that targeting PAR1 might be a promising treatment strategy. Recently Zhong et al showed that doxycycline is a direct inhibitor of PAR1-thrombin activation, with subsequent down-regulation of tumour cell migration and tumour growth (43). Furthermore Agarwal et al showed inhibition of angiogenesis, ascites formation and metastasis in xenograft models of peritoneal EOC by giving intracellular pepducins to disturb PAR1-MMP signalling systems (37).…”