Increased tissue factor expression is associated with reduced survival in non-small cell lung cancer and with mutations of TP53 and PTEN.
BACKGROUND
Tissue factor (TF), the main initiator of blood coagulation, is also a signaling protein that regulates cancer progression. TF synthesis was recently shown to be affected by tumor suppressor genes (TSGs) in tumor cell lines. We therefore studied TF gene (F3) expression and the status of genes coding for tumor protein p53 (TP53), phosphatase and tensin homolog (PTEN), and serine/threonine kinase 11 (STK11) in non-small cell lung cancer (NSCLC). Heparanase (HPSE) gene expression was also measured because this endo-beta-D-glucuronidase was recently shown to enhance TF gene expression.


METHODS
TF and heparanase mRNA expression was measured by real-time PCR in 53 NSCLC tumors. Exons 5-8 of TP53 were sequenced from genomic DNA. Mutations of PTEN and STK11 were screened by multiplex ligation-dependent probe amplification.


RESULTS
TF mRNA levels were significantly higher in T(3)-T(4) tumors (P = 0.04) and in stages III-IV of NSCLC (P = 0.03). Mutations of TP53, STK11, and PTEN were identified in 20 (37.7%), 21 (39%), and 20 (37.7%) of tumors, respectively. TF expression was higher in mutated TP53 (TP53(Mut)) (P = 0.02) and PTEN(Mut) (P = 0.03) samples. Moreover, TF mRNA increased from 2700 copies (no mutation) to 11 6415 when 3 TSG were mutated. Heparanase gene expression did not differ according to TF gene (F3) expression or TSG mutation. The median survival time was shorter in patients with tumor TF mRNA levels above median values (relative risk 2.2; P = 0.03, multivariate analysis) and when TP53 was mutated (relative risk 1.8; P = 0.02).


CONCLUSIONS
These results provide clear evidence that combined oncogene events affecting TSG dramatically increase TF gene expression in lung tumors. Moreover, this study suggests that TF gene expression could be used as a prognostic marker in NSCLC.
Regina
Sandra
S
Department of Hematology-Hemostasis, Trousseau Hospital and François Rabelais University, Tours, France.
Valentin
Jean-Baptiste
JB
Lachot
Sébastien
S
Lemarié
Etienne
E
Rollin
Jérôme
J
Gruel
Yves
Y
D000091162:AMP-Activated Protein Kinase Kinases; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000096:biosynthesis*; D002289:Carcinoma, Non-Small-Cell Lung / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D005260:Female; D005966:Glucuronidase / Q000096:biosynthesis; D006801:Humans; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009154:Mutation; D051059:PTEN Phosphohydrolase / Q000235:genetics*; D016133:Polymerase Chain Reaction; D016016:Proportional Hazards Models; D017346:Protein Serine-Threonine Kinases / Q000096:biosynthesis; D015996:Survival Rate; D013925:Thromboplastin / Q000096:biosynthesis*; D016159:Tumor Suppressor Protein p53 / Q000235:genetics*; D000099175:Heparanase
D000091162:AMP-Activated Protein Kinase Kinases; D014408:Biomarkers, Tumor; D005966:Glucuronidase; D051059:PTEN Phosphohydrolase; D017346:Protein Serine-Threonine Kinases; D013925:Thromboplastin; D016159:Tumor Suppressor Protein p53; D000099175:Heparanase; C495901:TP53 protein, human; C109790:STK11 protein, human