IMMUNOHISTOCHEMICAL EXPRESSION OF CD133 IN HIGH GRADE TRANSITIONAL CELL CARCINOMA OF THE URINARY BLADDER

Morooj Jassim Mohammed*, Bassim Shihab Ahmed and Adnan Ibraheem Ali

ABSTRACT

Background: Urothelial carcinoma (transitional cell carcinoma) of the urinary bladder, represents 90% of all primary tumors of this organ, and one of the most common ten malignancy in Iraq and worldwide. These tumors can range from low grade papillary neoplasms to less frequent more aggressive and invasive high grade tumors. More than 70% of superficial tumors recur, and about one-third of the patients have tumor progression, which can affect the quality of their life. Treatment failure, recurrence, and metastasis in bladder cancer are attributed to a subset of tumor cells expressing cancer stem cell (CSC) markers. CSCs have been isolated from leukemia and from a wide spectrum of solid tumors, including BC, using putative CSC markers such as OCT4, CD133, ALDH1, and CD44. • Aims of the study: This study aimed to provide a present outlook of urothelial carcinoma among Iraqi patients through the followings: To assess the immunohistochemical (IHC) expression patterns of CD133 1. in high grade of urothelial carcinoma 2. in the epithelium of normal looking bladder tissue 3. To evaluate the expression of CD133 marker and its association with the Clinico- pathological parameters. • Materials and Methods: cross sectional study which was carried out at the Department of Pathology and Forensic Medicine, at Al-Mustanssria college of medicine during the period from august 2017 to august 2018. A total number of 60 tissue samples were collected for the study, Patients were divided into two groups according to The pathological diagnosis of the bladder tissue Group A: 30 case with high grade TCC of bladder. Group B: (as a control group) 30case with apparently normal bladder tissue • Tissue immunohistochemical analysis was applied to investigate the expression patterns of CSC markers CD133 in bladder cancer samples. • Results: CD133, it was positive in 56.7% of specimens of group A, and16.6% in group B. Regarding CD133 and high grade group, for associated inflammation and necrosis, 87.5% of those without inflammation showed positive CD133 marker result with a significant association (P=0.039) Concerning vascular invasion, 71.4% of patients with vascular invasion showed negative CD133 marker result with a significant association (P=0.003), In the area of muscular invasion, all patients who were free of muscular invasion showed positive CD133 marker result with a significant association (P=0.016) The majority of patients who had glandular differentiation and sequamous metaplasia showed negative CD133 marker result (84.6%) with a significant association (P=0.001) The highest prevalence of positive CD133 marker result was seen in patients without prostate involvement (66.7%) with a significant association (P=0.027). • Conclusions 1-there was a significant expression of CSCs CD133 in transitional cell carcinoma. 2-there was an inverse correlation between the expression of cd133 and the pathological parameters of aggressiveness [muscular and vascular invasion and prostatic involvement] this may affirm that CD133 has a role in tumor initiation, but no role in tumor invasion and dissemination.

Keywords: Urothelial carcinoma, immunohistochemical (IHC).