PPACKII (trifluoroacetate salt) (Synonyms: H-D-Phe-Phe-Arg-Chloromethyl Ketone)

PPACKII is a specific and irreversible inhibitor of glandular and plasma kallikreins [1].

Human tissue kallikreins (hKs) are a class of secreted serine proteases that involved in the release of vasodepressor peptides or kinins from a plasma substrate. Kallikrein has diverse expression patterns and physiological roles. Kallikrein has been primarily known as cancer biomarkers. Kallikrein has been implicated in many cancer-related processes, such as cell-growth regulation, angiogenesis, invasion and metastasis. Kallikrein could promote or inhibit neoplastic progression individually and/or with the interaction in cascades with other hKs and proteases [2].

PPACKII prevented apolipoprotein proteolysis in dextran sulfate-precipitated human plasma LDL and inhibited serum atrial natriuretic peptide cleavage at micromolar concentrations [1]. It has been reported that PPACKII inactivated the amidolytic activity of native human Hageman Factor (Factor XII) at 5.3 μM [3].

References:
[1].  Byrne R E, Scanu A M. Apolipoprotein B-100 of plasma low density lipoproteins undergoes proteolysis by contact activation factors when plasma is treated with dextran sulfate-500-MgCl2[J]. Journal of lipid research, 1989, 30(1): 109-120.
[2].  Borgoo C A, Diamandis E P. The emerging roles of human tissue kallikreins in cancer[J]. Nature Reviews Cancer, 2004, 4(11): 876-890.
[3].  Silverberg M, Kaplan A P. Enzymatic activities of activated and zymogen forms of human Hageman factor (factor XII)[J]. Blood, 1982, 60(1): 64-70.