Plasminogen activators and their inhibitors in non-small cell lung cancer. Low content of type 2 plasminogen activator inhibitor associated with tumor dissemination.
BACKGROUND
Evidence suggests that plasminogen activators and their inhibitors play an important role in tumor spread.


METHODS
In this study, we measured the antigen levels of urokinase (u-PA), tissue plasminogen activator (t-PA), type 1 plasminogen activator inhibitor (PAI-1), and type 2 plasminogen activator inhibitor (PAI-2), and cancer tissue (19 adenocarcinomas and 19 squamous cell carcinomas) and normal lung tissue.


RESULTS
u-PA, PAI-1, and PAI-2 antigen levels in cancer tissue were significantly higher than those in normal tissue (P < 0.001 in u-PA and PAI-1; P < 0.005 in PAI-2), whereas t-PA antigen levels in cancer tissue were significantly lower than those in normal tissue (P < 0.005). In case with lymph node involvement (LN+ cases), PAI-2 antigen levels were significantly lower than those in cases without lymph node involvement (LN- cases) (P < 0.02), whereas there was no difference in either u-PA or PAI-1 antigen levels between these two groups. Furthermore, u-PA antigen levels showed a significant positive correlation with PAI-2 antigen levels in LN- cases (r = 0.696; P < 0.005), although there was no correlation between these two parameters in LN+ cases.


CONCLUSIONS
The antigen levels of u-PA, PAI-1, and PAI-2 in cancer tissue were significantly higher than those in normal tissue, and lower content of PAI-2 was associated with lymph node metastasis.
Nagayama
M
M
Department of Internal Medicine, Hamamatsu University, School of Medicine, Japan.
Sato
A
A
Hayakawa
H
H
Urano
T
T
Takada
Y
Y
Takada
A
A
D000230:Adenocarcinoma / Q000737:chemistry; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000941:Antigens / Q000032:analysis; D002289:Carcinoma, Non-Small-Cell Lung / Q000737:chemistry*; D002294:Carcinoma, Squamous Cell / Q000737:chemistry; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000737:chemistry*; D008207:Lymphatic Metastasis / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D017395:Plasminogen Activator Inhibitor 1 / Q000032:analysis*; D017396:Plasminogen Activator Inhibitor 2 / Q000032:analysis*; D010959:Tissue Plasminogen Activator / Q000032:analysis*; D014568:Urokinase-Type Plasminogen Activator / Q000032:analysis*
D000941:Antigens; D017395:Plasminogen Activator Inhibitor 1; D017396:Plasminogen Activator Inhibitor 2; D010959:Tissue Plasminogen Activator; D014568:Urokinase-Type Plasminogen Activator