[Correlation of LncRNA-PVT1 with Prognosis of Children with Acute Lymphoblastic Leukemia]

To investigate the expression of long non-coding RNA plasmacytoma variant translocation 1 (lncRNA-PVT1) in children with acute lymphoblastic leukemia (ALL) and its correlation with prognosis.

Clinical data of 64 children with ALL were retrospectively analyzed. All children received standardized treatment according to CCLG-ALL-2015 protocol, and their overall survival (OS) was followed up. Bone marrow examination and lncRNA-PVT1 examination were performed before first diagnosis (T1), early intensive therapy (T2), consolidation therapy (T3), delayed intensive therapy (T4), and maintenance therapy (T5). Bone marrow samples of 25 children with thrombocytopenic purpura were collected during the same period as control group. LncRNA-PVT1 expression was compared between ALL group and control group. ALL children were divided into high-risk group and non-high-risk group according to the risk factors at T3, and the expression changes of lncRNA-PVT1 were analyzed. The correlation of lncRNA-PVT1 with clinical features and prognosis of ALL children was analyzed.

The expression of lncRNA-PVT1 in ALL children was significantly higher than that in control group (P < 0.001). ROC curve analysis showed that the area under curve (AUC) of lncRNA-PVT1 for ALL diagnosis was 0.919(95%CI : 0.863-0.975), the optimal cut-off value was 1.465, sensitivity was 87.50%, and specificity was 98.80%. ALL children were divided into low lncRNA-PVT1 group (lncRNA-PVT1< 2.18) and high lncRNA-PVT1 group (lncRNA-PVT1≥2.18) according to the median lncRNA-PVT1 value (2.18). The high lncRNA-PVT1 group had higher Day 33 MRD compared with low lncRNA-PVT1 group (P < 0.01). At T3, T4 and T5, the expression of lncRNA-PVT1 in high-risk group was significantly higher than that in non-highrisk group (all P < 0.01). The expression of lncRNA-PVT1 were significantly increased in high-risk group at 5 time points (P < 0.001), while, there was no significant difference in non-high-risk group (P >0.05). The median OS of low lncRNA-PVT1 group was 35(9-37) months, which was significantly higher than 25(5-33) months of high lncRNA-PVT1 group (P < 0.01). Univariate and multivariate Cox regression analysis showed that Day 33 MRD (>10^-2) and lncRNA-PVT1 (≥2.18) were independent risk factors for OS in ALL children (both P < 0.05).

LncRNA-PVT1 is involved in the pathogenesis of ALL in children and closely related to the prognosis.