Immunohistochemical expression of NANOG in urothelial carcinoma of the bladder

ABSTRACT

Urothelial carcinoma is a common malignant neoplasm that has a poor prognosis and a high frequencyof recurrence and metastasis. Constant disease surveillance with periodic and long term cystoscopyexamination is necessary for management of the disease. However, the monitoring and therapyregimen is expensive, incurring a massive burden to patients and the government. Therefore, thedevelopment of specific biomarkers for urothelial carcinoma at an early stage and recurrence detectionbecomes a priority. Homeobox genes are a family of genes that are involved in tumourigenesis.They might be potential prognostic markers for urothelial carcinoma. The study investigated theexpression pattern of NANOG which is one of a homeobox gene in different stages and grades ofurothelial carcinoma. NANOG expressions were also correlated with patient demographic factors andclinicopathological parameters. The expression of NANOG in 100 formalin-fixed paraffin-embeddedurothelial carcinoma tissues was determined by immunohistochemistry. Immunohistochemistryshowed positive expression of NANOG in all specimens with detection in the cytoplasm, nucleiand the nuclear membrane of the cancer cells. The immunohistochemical expression of NANOGincreased across stages and grades of the tumour. The expression of NANOG was not significantlyassociated with demographic factors; gender (p = 0.376), race (p = 0.718) and age (p = 0.058) aswell as with most of the clinicopathological parameters; pathological stage (p = 0.144), grade (p =0.625), lymph node involvement (p = 0.174) and distant metastasis (p = 0.228). However, NANOGexpression showed significant correlation with tumour invasion (p = 0.019). We concluded thatNANOG might be a potential biomarker for early diagnosis of urothelial carcinoma of the bladder.