Background/aims: Autophagy is crucial for the survival and function of plasma cells including protection from toxic misfolded immunoglobulin and proper energy metabolism. Multiple myeloma (MM) is an indolent but eventually fatal neoplasm of plasma cells. Autophagy may play a critical role in the survival of MM cells and their response to chemotherapeutic agents. In this study, we correlated the expression of autophagy-related proteins with the prognosis of MM.
Methods: In this retrospective cohort study, we examined the expression of the autophagic markers BECLIN 1 and microtubule-associated protein light chain 3 (LC3) in 89 cases of MM biopsied from 2001 to 2004 at the Asan Medical Center. The association of the expression scores of these markers with clinical outcomes was assessed.
Results: Patients with strong immunoreactivity to BECLIN 1 or LC3 had a significantly better overall survival (OS) than patients with negative to moderate immunoreactivity (p = 0.036 and 0.018, respectively). This was also true for disease-specific survival (DSS; p = 0.051 and 0.043, respectively). In addition, LC3 immunostaining remained an independent factor impacting OS (p = 0.028) and DSS (p = 0.020) after multivariate analysis.
Conclusions: The results of this study suggest that higher immunoreactivity for autophagic markers in MM is associated with superior patient survival.