Not elevated values of uPA and PAI-1 showed a lower rate of proliferation (average 8.5%) than carcinomas with an increase of uPA and/or PAI-1 (average 13.9%); p = 0.054, Student's t-test.
The current results showed that LC is related to combined thrombophilic gene mutations and individuals with homozygosity of 4G in PAI-1 and MTHFR C677T genes and heterozygosity of FV Leiden, Apo E4 genes have a germ-line risk for LC tumorigenesis.
Investigating specific PAI-1 expressing cells in oral carcinomas by immunohistochemistry, we found that PAI-1 was expressed in 18 of the 20 patients, mainly by cancer cells.
PAI-1 mRNA was detected in 13 of the 16 carcinomas and in 8 of the 9 benign hyperplasias, located in scattered fibroblast-like cells in both groups, in some vascular structures and in a few macrophages located in the interstitial tissue of both malignant and benign lesions.
By generating immunodeficient mice (in Rag-1-/- or nude background) deleted for PAI-1 gene (PAI-1-/-), we have evaluated the impact of host PAI-1 deficiency on the tumorigenicity of two malignant human skin keratinocyte cell lines HaCaT II-4 and HaCaT A5-RT3 forming low-grade and high-grade carcinomas, respectively.
In addition, PAI-1 transcripts were more abundant in poorly and moderately differentiated carcinomas relative to well-differentiated carcinomas and PAI-2 transcripts were more abundant in squamous cell carcinomas than in adenocarcinomas.