Expression and Function of FAM72A Gene in Multiple myelomaFAM72A.

Aims: This study aims to comprehensively investigate the role of Family Member A with sequence similarity 72-A (FAM72A) in multiple myeloma.

Background: Multiple myeloma poses significant challenges. This study delves into FAM72A's impact on key cellular processes, shedding light on potential therapeutic targets and enhancing our understanding of multiple myeloma progression.

Objective: Investigate the impact of FAM72A on the proliferation, apoptosis, and bortezomib sensitivity of multiple myeloma cell line U266.

Methods: qRT-PCR analyzed FAM72A expression levels in bone marrow samples from 30 patients with multiple myeloma and 10 healthy donors at the Second Hospital of Shanxi Medical University. Cell lines overexpressing FAM72A were constructed, and Cell Counting Kit 8 (CCK-8) and flow cytometry were used to assess U266 cell proliferation, apoptosis, and sensitivity to bortezomib. Biological predictions for FAM72A were performed to find transcription factors binding to the FAM72A promoter region, verified using a luciferase assay. U266 cells were transfected with si-POU2F2 (POU class 2 homeobox 2), and the impact on cell proliferation was validated. Western blot analysis detected the expression of downstream proteins in the p53 signaling pathway. In vivo, experiments established a xenograft mouse model further to study the role of FAM72A in multiple myeloma.

Results: FAM72A was upregulated in multiple myeloma bone marrow tissues. Compared to the OE-NC group, the OE-FAM72A group showed increased Mouse Double Minute 2 homolog (MDM2) expression, decreased p53 expression, increased cell proliferation, and decreased apoptosis. POU2F2 was identified as the upstream transcription factor for FAM72A. Compared to the si-NC group, the si-POU2F2 group exhibited decreased MDM2 expression, increased p53 expression, slowed cell proliferation, and increased apoptosis. Silencing POU2F2 could reverse the pro-proliferative effect of over-expressing FAM72A in U266 cells. In vivo experiments in a xenograft mouse model further studied the role of FAM72A in multiple myeloma.

Conclusion: Overexpression of FAM72A promotes U266 cell proliferation, inhibits apoptosis, and reduces sensitivity to bortezomib by regulating the POU2F2/FAM72A/p53 signaling pathway.