Clinicopathological significance of the hypermethylation in multiple myeloma, a systematic review and meta-analysis.

It is well known that the loss of function of the gene is mainly caused by the hypermethylation of the gene; however, whether or not the inactivation is associated with the clinical significance of multiple myeloma (MM) remains elusive. A meta-analysis was conducted to quantitatively determine the role of the hypermethylation in the clinical significance of MM. We demonstrated that MM patients show much higher hypermethylation rates on the gene in bone marrow compared to normal individuals, as well as monoclonal gammopathy of undetermined significance (MGUS). The difference of aberrant hypermethylation between MM patients in advanced stage and MM patients in early stage is not statistically significant. Interestingly, the survival rate of MM patients with the hypermethylation is much shorter compared to those without the hypermethylation. Our results demonstrate that hypermethylation status of the gene may play a role in the progression of MGUS to MM, as well as worse survival in MM. The hypermethylation, which induces the loss of function of the gene that plays a critical role in the early tumorigenesis of MM.