Effect of MYC and EZH2 expression on clinical and prognosis in plasma cell neoplasms

Effect of Myc and EZH2 Expression on Clinical and Prognosis in Plasma Cell Neoplasms Background and Aim: Multiple myeloma (MM) is characterized by the neoplastic proliferation of plasma cells that produce monoclonal immunoglobulin. MM molecular pathogenesis is a hihgly complex and heterogeneous disease. MM pathogenesis is a multi-step process consisting of genetic and epigenetic changes. Rearrangements involving the MYC protooncogene are common in newly diagnosed MM, but their prognostic significance is still unclear. EZH2 aberration has been seen in a wide range of cancers, including several categories of B cell and T cell lymphoid malignancies, and it is associated with poor clinical prognosis and outcomes. The purpose of this study was to assess the impact of MYC rearrangement and EZH2 overexpression on clinical characteristics, treatment response, and survival in newly diagnosed MM. Material and Method: 92 cases diagnosed with newly diagnosed plasma cell neoplasia followed at the Faculty of Medicine of Çukurova University between 2005-2019 were selected. EZH2 was evaluated by immunohistochemistry (IHC) method. Myc was evaluated using IHC and FISH methods. Statistically, survival and response to treatment analysis of the patients were performed. Results: In the our study; 65.2% (n: 60) of the patients were male, 34.8% (n: 32) were female. Median age was 58.5 (min:21-max:83). 24.4% of the patients showed EZH2 positive, 18.5% Myc IHC positive, 26.7% Myc FISH positive, and 7.7% EZH2 and Myc IHC positive. Overall survival was significantly shorter in EZH2 positive patients, while survival time was found to be shorter in EZH2 and Myc positive patients than in patients with only EZH2 positive. Conclusion: EZH2 and Myc show poor prognostic features in MM. Targeting and treating these two parameters, which have been shown to affect biology badly, can open new horizons for these patients. Keywords: MM, EZH2, MYC