Diffuse large B‑cell lymphoma (DLBCL) is the most common type of non‑Hodgkin lymphoma worldwide. Several studies have indicated that Homo sapiens (hsa)‑microRNA (miR)‑429 exerts a tumor‑suppressive effect on a variety of malignant tumors. To the best of our knowledge, the molecular function and mechanism of action of hsa‑miR‑429 in DLBCL have not been evaluated to date. The present study demonstrated that the expression of hsa‑miR‑429 in DLBCL cells was significantly reduced. hsa‑miR‑429 inhibited the proliferation of the DLBCL cell lines, SUDHL‑4 and DB, and promoted apoptosis. A dual luciferase reporter assay was used to demonstrate that chromobox 8 (CBX8) was the target gene of hsa‑miR‑429. Overexpression of CBX8 promoted the proliferation of SUDHL‑4 and DB cells and inhibited apoptosis, thereby playing a cancer‑promoting role. Transfection of hsa‑miR‑429 mimic into DB cells overexpressing CBX8 antagonized the effect of CBX8 on the proliferation of DB cells. Moreover, the apoptotic rate was increased in DB cells overexpressing CBX8 and transfected with hsa‑miR‑429 mimic, while the proportion of cells in the G2/M phase was significantly reduced. These results demonstrated the antagonistic effect of hsa‑miR‑429 on the oncogenic function of CBX8. Therefore, in DLBCL, the tumor suppressor effect of hsa‑miR‑429 may be achieved by targeted downregulation of CBX8, suggesting that hsa‑miR‑429 may be used as a diagnostic marker and a potential nucleic acid drug for DLBCL. CBX8 may also represent an effective therapeutic target for DLBCL.
Keywords: apoptosis; cell proliferation; chromobox 8; diffuse large B‑cell lymphoma; hsa‑microRNA‑429.