The Study On The Expressions And Significance Of EGFR,AKT And PTEN In Human Bladder Tumors

Objective To investigate the expression of EGFR, AKT ,PTEN and their relationships with clinic characters of human bladder urothelial carcinomas.Methords A total of 20 frozen bladder cancers and 10 normal tissues from 2005 to 2006 were collected from the Department of Pathology in the First Affiliated Hospital of Zhejiang University. RT-PCR was used to detect EGFRmRNA, AKT mRNA and PTENmRNA expressions in tumors and normal tissues. Statistical analyses were done. A total of 65 paraffin-embeded human bladder cancers and 15 normal tissues were also obtained from 1998 to 2003. The expressions of EGFR, AKT and PTEN were detected by im- munohistochemistry. Statistical annlyses were also done.Results RT-PCR showed that EGFRmRNA, AKT mRNA and PTENmRNA expressions in the tumors were 1.98±1.08, 1.66±1.1 land0.92±0.35 respectively, while in the normal tissues the values were 0.67±0.49, 0.81±0.29 and 1.97±0.63 respectively. The expression levels of EGFR and AKT in tumors were significantly higher than those in normal tissues(p<0.05), while PTEN was higher in normal tissues than that in tumors (p<0.05). A positive correlation was observed between EGFR and AKT (r==0.639, p=0.002), while there was negative correlation between EGFR and PTEN (r= -0.649, p=0.037) and between AKT, PTEN a negative correlation but no statistical meaning was proved (r=—0.255, p =0.278 ) .The expressions of EGFR and AKT were higher in the high grade and invasive tumors than those in the low grade and superficial ones, while PTEN had the different results. Immunohistochemistry showed that the positive stainings of EGFR and AKT were located in the cytoplasm and(or) cell surface of the tumor cells, PTEN was located in the cytoplasm. The protein levels of EGFR and AKT in the tumors were higher than those in the normal tissues (p<0.05), while PTEN was higher in the normal tissues than that in the tumors. There were positive relations in EGFR and AKT with tumor grade, clinical stage and recurrence (p<0.05), while in PTEN a different result was detected.Conclusion 1. The hyperexpressions of EGFR and Akt may play an important role in the initiation and development of human bladder carcinomas, while PTEN inhibits those processes. 2 .There are positive relationships between the expressions of EGFR and PTEN with tumordifferentiation, clinical stage and recurrence, which may be useful to evaluate the aggressiveness and prognosis of tumors.