Relationship between grade and MDM2 oncoprotein overexpression in transitional cell carcinoma of the urinary bladder

Transitional cell carcinoma (TCC) of the urinary bladder is the second common cancer of the genitourinary tract. Several parameters such as clinical and pathological parameters, molecular factors, and etc play a role in determination of prognosis and type of treatment. In this research study, the relationship between grade and MDM2 oncoprotein overexpression in TCC of bladder was evaluated. This cross-sectional study was carried out on 75 paraffinembeddedtissue blocks (deposited in Pathology Department) from patients with TCC of urinary bladder from 2002 to 2005. In this respect, 3 μm sections were taken from each block. In one of the sections, grade of tumor was determined according to WHO/ISUP criteria using hematoxylin-eosin staining method. In another section, percent of MDM2 positive cells were determined by microscopic observation of 100 cells in each section using immunohistochemical technique and specific antibody. Mean of MDM2 positive cells was %9.08 ± 4.7. In addition, mean of MDM2 positive cells in low malignant potential tissue (grade I), low grade tissue (grade II), and high grade tissue (grade III) was %3.6 ± 2.2, %8.2 ±3.5, and %13.1 ± 3.4 respectively. Meanwhile, a significant relationship was found out between grade and overexpression of MDM2 oncoprotein (p = 0.012). Overexpression of MDM2 oncoprotein exhibits a direct relationship with grade of TCC of the urinary bladder. The obtained results were consistent with the most previous studies. Therefore, through performing studies with a greater follow-up and entailing a larger population of patients, overexpression of MDM2 oncoprotein could be used as a prognostic parameter in TCC of urinary bladder.