Gene mutations in newly diagnosed multiple myeloma patients detected by next-generation sequencing technology

Background

Multiple myeloma (MM) is a heterogeneous plasma-derived hematopoietic malignancy with complex genetic mutation contributing to the pathogenesis. Though gene sequencing has been applied in MM, genetic features from Chinese MM patients are reported less. We investigated the genetic mutation of newly diagnosed multiple myeloma (NDMM) patients and explore its correlation with cytogenetic abnormalities detected by fluorescence in situ hybridization (FISH).

Methods

A total of 206 patients with NDMM were enrolled. After enriching plasma cells with CD138 magnetic beads, 92 MM-related target gene mutations were detected by the Illumina sequencing platform, and six common genetic abnormalities were detected by FISH.

Results

162 cases (78.6%) had at least one gene mutation detected by NDMM. The top 5 mutated genes were KRAS, NRAS, TRAF3, BRAF, and TP53. Cytogenetic abnormalities detected by FISH have a certain correlation with gene mutations, t(11;14) translocations are often accompanied by CCND1 and TP53 mutations, KLHL6 in t(4;14), SP140, CDKN1B and PRKD2 in t(14;16) and t(14;20) translocations. The mutation ratio was higher for EGR1, while lower of CCND1 in patients with gain 1q21. The TP53 mutation was more likely in patients with 17p deletion. The gene mutation affects the pathway of the RNA process is more frequently occurring in males and age less than 70 years patients. The International Staging System (ISS) Stage III correlated with gene mutations in the NK-κB pathway while Revised ISS (R-ISS) Stage III correlated with the DNA damage repair pathway.

Conclusions

There are various gene mutations in NDMM patients, mainly RAS/MAPK and NF-κB pathway gene pathways.