Inverse agonism at the Na/K-ATPase receptor reverses EMT in prostate cancer cells.
Prostate
; 81(10): 667-682, 2021 07.
Article
in En
| MEDLINE
| ID: mdl-33956349
ABSTRACT
The surface expression of Na/K-ATPase α1 (NKA) is significantly reduced in primary prostate tumors and further decreased in bone metastatic lesions. Here, we show that the loss of cell surface expression of NKA induces epithelial-mesenchymal transition (EMT) and promotes metastatic potential and tumor growth of prostate cancer (PCa) by decreasing the expression of E-cadherin and increasing c-Myc expression via the activation of Src/FAK pathways. Mechanistically, reduced surface expression of NKA in PCa is due to increased endocytosis through the activation of NKA/Src receptor complex. Using a high-throughput NKA ligand-screening platform, we have discovered MB5 as an inverse agonist of the NKA/Src receptor complex, capable of blocking the endocytosis of NKA. MB5 treatment increased NKA expression and E-cadherin in PCa cells, which reversed EMT and consequently decreased the invasion and growth of spheroid models and tumor xenografts. Thus, we have identified a hitherto unrecognized mechanism that regulates EMT and invasiveness of PCa and demonstrated for the first time the feasibility of identifying inverse agonists of receptor NKA/Src complex and their potential utility as anticancer drugs. We, therefore, conclude that cell surface expression of α1 NKA can be targeted for the development of new therapeutics against aggressive PCa and that MB5 may serve as a prototype for drug development against EMT in metastatic PCa.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Prostatic Neoplasms
/
Sodium-Potassium-Exchanging ATPase
/
Drug Inverse Agonism
/
Epithelial-Mesenchymal Transition
Limits:
Animals
/
Humans
/
Male
Language:
En
Journal:
Prostate
Year:
2021
Document type:
Article
Affiliation country: