Background: EZH2 is a histone methyltransferase that suppresses genes involved in cell cycle control. Overexpression of EZH2 has been associated with a poor prognosis in various malignancies. Pawlyn et al recently reported poor outcomes in patients with multiple myeloma and overexpression of EZH2. In order to validate these findings, we analyzed EZH2 expression and outcomes among patients from the CoMMpass study. Patients and Methods: We extracted clinical, expression, and genomic data from Interim Analysis 13 of the MMRF CoMMpass study, which harbors data from over 1000 patients with multiple myeloma. Correlations were drawn between EZH2 expression and common genetic mutations. We analyzed the association of EZH2 overexpression with progression-free (PFS) and overall survival (OS). Results: The estimated median PFS for patients with EZH2 overexpression was 20.2 months (95% confidence interval [CI], 16.3-25.5 months) compared with 37.2 months (95% CI, 31.5-40.7 months) for patients without (P <.001). The estimated median OS for patients with EZH2 overexpression was 52.3 months (95% CI, 38.5 months to unable to quantitate), whereas the median OS had not been reached for those without (P <.001). EZH2 overexpression was more common in those with 17p and 1q deletions, TP53 missense mutations, and certain KRAS mutations. Coinciding BRAF and EZH2 amplification occurred frequently. Conclusion: EZH2 overexpression is associated with worse outcomes among patients with multiple myeloma from the CoMMpass study. Its known association with p53 and other drivers of malignancy support further lab-based and clinical study in multiple myeloma.
- CoMMpass study