Prospective quantitative gene expression analysis of kallikrein-related peptidase KLK10 as a diagnostic biomarker for childhood acute lymphoblastic leukemia

BACKGROUND: The most common malignancy in children is acute lymphoblastic leukemia (ALL). This study aimed to explore KLK10 mRNA expression as a potential diagnostic biomarker for ALL in children and to examine the effect of chemotherapy on KLK10 mRNA expression following the induction and after three months of receiving chemotherapy. METHODS: In this prospective study, total RNA was extracted from blood samples of 23 pediatric ALL patients on diagnosis, after one month and three months of receiving chemotherapy. Healthy pediatric volunteers (n = 12) were selected as control individuals. After cDNA synthesis, KLK10 mRNA gene expression levels were quantified using quantitative real-time PCR (qRT-PCR). RESULTS: KLK10 mRNA expression levels were significantly decreased in leukemic cells compared to their levels in cells of normal blood samples (p = 0.0001). KLK10 expression levels in ALL patients after one month and three months of receiving chemotherapy decreased compared to normal blood samples (p < 0.0001 and p = 0.0175 respectively). The expression level of KLK10 mRNA in ALL patients after one month of chemotherapy was decreased compared to their level on diagnosis (p = 0.4413). KLK10 mRNA expression levels in ALL patients after three months of chemotherapy were increased compared to their level on diagnosis (p = 0.0602). The ROC curve illustrated that KLK10 mRNA expression could very efficiently discriminate ALL patients from normal counterparts (AUC=0.886, 95% CI [0.7720–1.000], SE = 0.0582, p = 0.0004). CONCLUSION: KLK10 mRNA expression could serve as a potential diagnostic molecular biomarker for ALL in children.