Table 1.
Basic characteristics of the included studies
| Study/country | Patients
|
Methods | Primary aim | Methylation site | |
|---|---|---|---|---|---|
| MGUS | MM | ||||
| Ng et al25/People’s Republic of China | 12 | MSP | Investigate whether p16/p15 genes are inactivated by hypermethylation of the 5′ CpG islands | Promoter, CpG islands | |
| Fan et al20/People’s Republic of China | 24 | MSP | Study the action, characteristics, and expression of high methylation of p15 and p16 genes in MM | Promoter, CpG islands | |
| Wu et al28/People’s Republic of China | 12 | MSP | Study the effect of operative region hypermethylation gene in human malignant hematopoietic tumors | Promoter, CpG islands | |
| Guillerm et al23/France | 33 | 33 | MSP | Determine how and when the alterations of p15 and p16 contribute to tumorigenesis | Promoter, CpG islands |
| Chen et al18/People’s Republic of China | 22 | MSP | Investigate the frequency of p16 and p15 methylation and its relationship with bone marrow cell apoptosis and clinical outcome | Promoter, CpG islands | |
| Guillerm et al22/France | 61 | MSP | Investigate different prognostic values of p15 and p16 gene methylation in MM | Promoter, CpG islands | |
| Galm et al21/Germany | 3 | 56 | MSP | Gain insight into specific pathways that are relevant in the multiple step transformation process of normal plasma cells to MM | Promoter, CpG islands |
| Seidl et al26/Austria | 29 | 113 | MSP | Investigate the methylation frequencies of ten genes in MGUS and compare with MM | Promoter, CpG islands |
| Chim et al19/People’s Republic of China | 13 | MSP | Study the frequency and whether multiple genes are methylated in any one individual | Promoter, CpG islands | |
| Martin et al24/Spain | 13 | 30 | MSP | Explore the role of DNA methylation in plasma cell disorders | Promoter, CpG islands |
| Braggio et al17/Brazil | 68 | MSP | Gain insights on the prognostic implication resulting from epigenetic silencing | Promoter, CpG islands | |
| Stanganelli et al27/Argentina | 21 | 44 | MSP | Determine the role of aberrant promoter methylation as one of the steps involved in the progression of MGUS to MM | Promoter, CpG islands |
Abbreviations: MGUS, monoclonal gammopathy of undetermined significance; MM, multiple myeloma; MSP, methylation-specific polymerase chain reaction.