Background: Glucocorticoid response, as one of the most reliable prognostic factors, plays a pivotal role in predicting clinical outcome in the acute lymphoblastic leukemia (ALL). Hence, identifying potential biomarkers of glucocorticoid resistance can help to decide on the best treatment for ALL. On the other hand, the relationship between increased fatty acid synthase (FASN) expression and poor clinical prognosis has been reported in various kinds of cancer. So here, we aimed to evaluate the prognostic value of FASN in ALL.

Materials and Methods: In this study, we investigated FASN expression level in glucocorticoid-resistance and sensitive leukemia cell lines, REH and NALM-6, before and after glucocorticoid (prednisolone and dexamethasone) treatment using quantitative RT-PCR. Then, we evaluated the prognostic and the diagnostic value of FASN in bone marrow samples of children with acute lymphoblastic leukemia.

Results: Our results indicated there was no significant difference in expression level of FASN in REH resistance cells after glucocorticoids treatment, while decreased FASN expression was observed in NALM-6 sensitive cells. Additionally, we reported FASN overexpression in ALL samples in comparison with non-cancerous controls, particularly in high-risk samples (p < 0.002).

Conclusions: This study suggests that increased expression of FASN may play a pivotal role in the development of ALL. Also, FASN could be considered as a potential marker of the poor prognosis in pediatric ALL.