FOXO3 suppresses lymphoma progression through promoting miR-34b/HSPG2 axis

Diffuse large B-cell lymphoma (DLBCL) is the most common type of lymphoma, which caused many patients to lose their precious lives. FOXO3 was a suppressor in various cancers, however, the role and mechanism of FOXO3 in DLBCL remain unclear.

Bioinformatics analysis was used to offer information FOXO3 expression and its expression for prognosis of DLBCL patients. The abundance of genes and proteins was evaluated using RT-qPCR and western blot. Cell proliferation and apoptosis was detected by CCK-8 and flow cytometry. The interactions among FOXO3, miR-34b, and HSPG2 were predicted by TransmiR and Starbase and validated using dual luciferase reporter assay, ChIP assay, and RIP assay.

Our findings revealed that FOXO3 expression was abnormally declined in DLBCL cells. FOXO3 upregulation restrained cell proliferation and promoted cell apoptosis of DLBCL cells, while miR-34b inhibitor eliminated these influences. Similarly, miR-34b mimic suppressed malignant behaviors of DLBCL cells, which were abolished by HSPG2 overexpression. Mechanically, FOXO3 induced miR-34b expression through interacting with miR-34b promoter and HSPG2 was a targeted gene of miR-34b.

FOXO3 attenuated the capability of cell proliferation and promoted cell apoptosis rate of DLBCL cells through affecting miR-34b/HSPG2 axis, therefore inhibiting DLBCL progression.