UK122 HCl

UK122 HCl is the hydrochloride salt form of UK122（CAS No.：940290-58-4）。UK122 is a small-molecule selective urokinase-type plasminogen activator（uPA, Urokinase-type plasminogen activator）inhibitor，which selectively inhibits uPA serine protease activity（the enzymatic IC₅₀ for uPA is 0.2 μmol/L，while the IC₅₀ values for homologous enzymes such as tPA、plasmin、thrombin、and trypsin are all >100 μmol/L，with >500-fold selectivity）。By blocking uPA-mediated plasminogen activation，it reduces extracellular matrix degradation in tumors、inhibits tumor cell invasion and migration，remodels the immune microenvironment、increases CD8⁺T cell infiltration and cytotoxicity，and acts synergistically with immune checkpoint inhibitors to exert antitumor effects；in airway smooth muscle，it inhibits downstream plasmin-mediated ERK1/2、PI3K/Akt and EGFR transactivation pathways，suppressing abnormal smooth muscle cell proliferation；in hypertension-related cerebrovascular lesions，it can inhibit abnormal vascular wall remodeling and reduce the risk of vascular rupture，and this vascular protective effect is not directly dependent on a reduction in blood pressure.

At the cellular level，UK122 is commonly used at a concentration gradient of 11.1–100 μM in CFPAC-1 pancreatic cancer cells；100 μM can inhibit cell migration by approximately 80% and invasion by approximately 68%，without significant cytotoxic effects on cell proliferation；in primary human airway smooth muscle cells（ASM cells），10 μM is commonly used and can effectively block plasminogen-induced cell proliferation and cyclin D1 upregulation；in HepG2 human liver cancer cells，10 μM UK122 combined with sorafenib（Sorafenib，CAS No.：284461-73-0，Catalog No.：A3009）can enhance the inhibition of cell proliferation and induction of apoptosis，and can reverse sorafenib resistance.

In animal experiments，UK122 is primarily administered therapeutically in disease models：in a mouse model of hypertensive intracerebral hemorrhage induced by angiotensin II combined with L-NAME，daily intraperitoneal injection of 4 mg/kg can significantly delay the onset of intracerebral hemorrhage；in a mouse model of subcutaneously transplanted RM-1 prostate cancer，the same dose and administration regimen（4 mg/kg，daily intraperitoneal injection）can inhibit tumor growth，and shows synergistic antitumor effects when combined with an anti-PD-1 antibody.

References：

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