THBS1 Is a Novel Serum Prognostic Factors of Acute Myeloid Leukemia

Abstract

Dysregulation of cytokines and growth factors is a general feature of tumor microenvironment, and unraveling the expression spectrum of cytokine and growth factor in niche is of utmost importance. Here, we evaluated cytokine profiling of bone marrow serum samples in AML patients and healthy controls. Protein expression profiling of serum from nine AML patients and five healthy controls was obtained using a biotinylated antibody chip. A total of 507 cytokines and growth factors were analyzed. Compared with healthy people, AML patients expressed 31 signature proteins, among which, 27 were significantly higher expressed and 4 proteins were lower. When patients were divided into favorable and poor prognosis, 12 signature proteins were significantly differentially expressed between these two groups. Furthermore, in order to identify the accuracy of cytokine expression profiles, we verified and analyzed the expression of THBS1 (Thrombospondin 1) in 116 patients and 9 healthy people. We found that THBS1 was lowly expressed in AML patients, which might be induced by promoter methylation, and patients with low THBS1 possessed shorter survivor time. Our data indicated that we successfully unveil differentially expressed proteins in AML patients using a biotinylated antibody chip; among them, THBS1 may be a potential therapeutic target for AML patients' treatment.

Keywords: Acute myeloid leukemia; THBS1; promoter methylation; protein microarray; serum protein markers.

Figure 1

Differential abundance of serum cytokines in AML patients and normal controls. (A) Hierarchical clustering analysis of cytokine profiles based on the top 31 genes in AML patients and healthy controls. (B) Biological process revealed the significant association of the genes with different expression in each group, column length: –log(P). (C) Heatmap of Kyoto Encyclopedia of Gene and Genomes (KEGG) enriched terms colored by P-values. (D) Hierarchical clustering analysis of cytokine profiles based on the top 12 genes in AML patients. (E) Biological process enriched terms colored by P-value, column length: –log(P). (F) KEGG enriched terms colored by P-values. (G–I) The top three enriched pathway in AML patients and healthy control analyzed by gene set enrichment analysis (GSEA).

Figure 2

Expression of THBS1 in the AML patients and normal control serum samples. (A) Expression level of THBS1 in 116 AML patients and 9 healthy controls. (B) Serum expression of THBS1 in AML patients with favorable, intermediate, and poor prognosis. (C) Kaplan–Meier survival curves estimated overall survival of patients with different expression of THBS1. (D–F) Kaplan–Meier estimated overall survival of serum THBS1 expression in patients with intermediate/poor prognosis, intermediate prognosis, and poor prognosis group. (G–I) Kaplan–Meier survival curves estimated overall survival of treatment with HSCT in patients with intermediate/poor prognosis, intermediate prognosis, and poor prognosis group. (J,K) Overall survival analysis of HSCT treatment in patients with high and low serum THBS1 expression patients. *P < 0.05, **P < 0.01.

Figure 3

Methylation of THBS1 in AML patients and normal controls. (A) MSP analysis of THBS1 methylation in AML patients and healthy controls, and AML cell lines. M and U represent MSP results using primer for methylated and unmethylated THBS1 genes, respectively. (B) The methylation status of CpG island in the THBS1 gene promoter of MV4-11 and HL-60 cells; each row of circles represents a single clone, and open circles represent unmethylated cytosine and filled circles represent methylated cytosine. (C) Expression of THBS1 in AML patients and healthy controls based on the GSE 13164 dataset. (D) Expression of THBS1 in AML primary cells treated with decitabine (DAC) based on dataset GSE40871. (E) Methylation beta value of THBS1 3′-UTR in AML primary cells treated with decitabine (DAC) based on dataset GSE40871. (F) Methylation beta value of THBS1 S-Shelf and S-Shore in AML primary cells treated with decitabine (DAC) based on dataset GSE40871. (G) Methylation beta value of THBS1 3′-UTR, 5′-UTR in AML patients treated with decitabine (DAC) based on dataset GSE80762. (H) Methylation beta value of THBS1 N-Shore in AML patients treated with decitabine (DAC) based on dataset GSE80762. (I) Methylation beta value of THBS1 Island in AML patients treated with decitabine (DAC) based on dataset GSE80762. (J) Methylation beta value of THBS1 S-Shore, S-Shelf in AML patients treated with decitabine (DAC) based on dataset GSE80762. ns, no significant; **P < 0.01.