Abstract: Objective　To investigate the expression of Hedgehog signaling pathway related molecules BMI1 and Gli1 in children with nephroblastoma (NB) and their relationship with prognosis. Methods　Pathological specimens of NB tissues and adjacent normal tissues in 37 NB children were collected. The expression of BMI1 and Gli1 proteins in tumor tissues was observed by immunohistochemical staining, and the relationship of BMI1 and Gli1 protein expressions with clinicopathological characteristics and serum tumor markers in NB children were analyzed. The relationship between BMI1 and Gli1 expressions and NB prognosis in children were analyzed using a public database. Results　Among the 37 children, 14 were male and 23 were female, and the median age was 2 years (3 months to 6 years). The expressions of BMI1 and Gli1 in NB tissues were higher than those in normal tissues adjacent to cancer (P<0.01). BMI1-positive cells were observed in the tumor tissues of 37 children, while Gli1 positive cells were not detected in the tumor tissues of 16 children. Twenty-two NB children with high BMI1 expression were more likely to have distant metastasis and had the increased expression of serum alpha-fetoprotein and carbohydrate antigen-125 (CA-125), and the overall survival period was shorter. The differences were statistically significant (P<0.05). Increased Gli1 expression was not associated with clinicopathological features or prognosis in NB children. Conclusion　The expression of Hedgehog pathway related molecules BMI1 and Gli1 was increased in NB tumor tissues. BMI1 is positively correlated with tumor metastasis and poor prognosis and it may be an important factor in the development of NB.

Key words: nephroblastoma;　Hedgehog signaling pathway;　child