[LncRNA PVT1 Regulates the MiR-20a-5p/HMGA2 Signaling Axis to Affect Proliferation and Apoptosis of Diffuse Large B-Cell Lymphoma Cells].

OBJECTIVE

To investigate the effect of long non-coding RNA (lncRNA) PVT1 on proliferation and apoptosis of diffuse large B-cell lymphoma (DLBCL) cells and the underlying mechanisms.

METHODS

qRT-PCR was used to detect the expression of PVT1 in human B lymphoblastic cells IM-9 and DLBCL cells OCI-Ly1, OCI-Ly3, OCI-Ly4, and OCI-Ly10. OCI-Ly1 cells were divided into four groups: si-NC (negative control), si-PVT1, si-PVT1+miR-20a-5p inhibitor, and si-PVT1+miR-20a-5p inhibitor+si-HMGA2. OCI-Ly3 cells were divided into four groups: Control, PVT1, PVT1+miR-20a-5p mimic, and PVT1+miR-20a-5p mimic+HMGA2. Dual-luciferase reporter assay was performed to verify the targeting relationship between PVT1 and miR-20a-5p, as well as the targeting relationship between miR-20a-5p and HMGA2. CCK-8 assay was used to detect cell proliferative capacity. Flow cytometry was used to detect cell apoptosis, and Western blot was used to detect the expression of HMGA2 protein.

RESULTS

The expression of PVT1 in OCI-Ly1, OCI-Ly3, OCI-Ly4, and OCI-Ly10 cells was significantly higher than that in IM-9 cells. Dual-luciferase reporter assay confirmed that miR-20a-5p could bind specifically to PVT1, and HMGA2 is a target of miR-20a-5p. In OCI-Ly1 cells, the si-PVT1 group exhibited significantly reduced cell proliferation and HMGA2 protein expression (P <0.05) and markedly increased apoptosis (P <0.001) compared with the si-NC group; The si-PVT1 + miR-20a-5p inhibitor group exhibited significantly higher proliferation (P <0.01) and substantially lower apoptosis (P <0.001) than the si-PVT1 group; Furthermore, the si-PVT1 + miR-20a-5p inhibitor + si-HMGA2 group displayed significantly decreased proliferation (P <0.01) and dramatically elevated apoptosis (P <0.001) when compared with the si-PVT1 + miR-20a-5p inhibitor group. In OCI-Ly3 cells, the PVT1 group displayed significantly enhanced proliferation and elevated HMGA2 protein expression (P <0.05) with markedly reduced apoptosis (P <0.001) compared to the Control group. Conversely, the PVT1 + miR-20a-5p mimic group showed dramatically impaired proliferation (P <0.001) and substantially increased apoptosis (P < 0.001) versus the PVT1 group. Notably, the PVT1 + miR-20a-5p mimic + HMGA2 group rescued proliferation (P <0.05) and suppressed apoptosis (P <0.001) relative to the PVT1 + miR-20a-5p mimic group.

CONCLUSION

PVT1 promotes the proliferation and inhibits the apoptosis of DLBCL cells by regulating the miR-20a-5p/HMGA2 signaling axis.