Prognostic analysis of SYTL4 in acute myeloid leukemia.

Background: Acute myeloid leukemia (AML) is a highly heterogeneous hematological malignancy. The key problem lies in the complexity of the genome, so that drug resistance and relapse have become the main problems. Recent studies have found an association between synaptotagmin-like 4 (SYTL4) and drug resistance in triple-negative breast cancer and its high expression is correlated with poor prognosis; however, it is unclear whether this gene is associated with the prognosis of AML. This study aimed to investigate the role and action mechanism of SYTL4 in AML.

Methods: We downloaded gene expression profiles and corresponding clinical data from The Cancer Genome Atlas (TCGA) public database and conducted differential and survival analyses using the Limma and survival packages in R. The receiver operating characteristic (ROC) curve, univariate COX, and multivariate COX were used for gene prediction analysis. Co-expression analysis of SYTL4 was performed using Limma, and enrichment analysis of differentially expressed genes in the SYTL4 high- and low-expression groups was conducted. We performed immune cell infiltration using the CIBERSORTx algorithm.

Results: The expression level of SYTL4 was highest in the poor prognosis group, and lowest in the good prognosis group. Survival was better in the SYTL4 low expression group than that in the high expression group. The areas under the ROC curve for TCGA-Acute Myeloid Leukemia (TCGA-LAML) at 1, 3, and 5 years were 0.725, 0.683, and 0.787, respectively. Sushi repeat protein X-linked 2 (SRPX2), caveolae associated protein 2 (CAVIN2), and other genes were identified as positive regulators of SYTL4 expression, whereas lactoperoxidase (LPO), diacylglycerol lipase beta (DAGLB), and other genes were identified as negative regulators. Differentially expressed genes in the SYTL4 high- and low-expression groups were enriched in pathways such as the embryonic skeletal system and platelet alpha granules. Differences were observed in follicular helper T cells, Tregs, monocytes, and M2 macrophages between SYTL4 high- and low-expression groups.

Conclusions: SYTL4 expression negatively correlates with AML prognosis and may be associated with exosome secretion in AML.