Inhibition of tumor growth by plasminogen-related protein-B.
BACKGROUND
Various fragments of the fibrinolytic protein plasminogen can act as antiangiogenic factors and inhibit the growth of primary and metastatic tumors in mice. Plasminogen-related gene-B encodes a putative 9 kDa protein virtually identical to the plasminogen N-terminal activation peptide, a 77-amino acid motif that is liberated from the parent plasminogen molecule during conversion to the serine proteinase plasmin. Previous data have documented enhanced transcription of plasminogen-related gene-B in neoplastic tissues.


METHODS
We have tested the effects of recombinant versions of plasminogen-related protein-B and the plasminogen N-terminal activation peptide on the growth of tumors in mice, employing murine tumor cell lines implanted subcutaneously.


RESULTS
The recombinant plasminogen-related protein-B significantly inhibited the growth of primary tumors in mice, while recombinant plasminogen N-terminal activation peptide elicited only a slight inhibition of tumor growth.


CONCLUSIONS
These data suggest that plasminogen-related protein-B may have utility as a novel cancer therapeutic.
Lewis
V O
VO
Orthopaedic Research Laboratories, Massachusetts General Hospital and Harvard Medical School, Boston 02114, USA. volewis@mail.mdanderson.org
O'Reilly
M S
MS
Gehrmann
M
M
Llinás
M
M
Schaller
J
J
Weissbach
L
L
D020533:Angiogenesis Inhibitors / Q000494:pharmacology; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D018827:Carcinoma, Lewis Lung / Q000188:drug therapy / Q000473:pathology; D002455:Cell Division / Q000187:drug effects; D005354:Fibrosarcoma / Q000188:drug therapy / Q000473:pathology; D006131:Growth Inhibitors / Q000494:pharmacology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010446:Peptide Fragments / Q000494:pharmacology; D010958:Plasminogen / Q000494:pharmacology*; D011994:Recombinant Proteins / Q000494:pharmacology
D020533:Angiogenesis Inhibitors; D000970:Antineoplastic Agents; D006131:Growth Inhibitors; C118420:PLGLB1 protein, human; D010446:Peptide Fragments; D011994:Recombinant Proteins; D010958:Plasminogen