INCREASED APOPTOSIS IN LYMPHOMA BONE MARROW ERYTHROID CELLS: POSSIBLE ANEMIC PATHOPHYSIOLOGIC SIGNIFICANCE

Objective: To investigate whether excessive erythroid cell apoptosis and/or suppression of proliferation would be implicated in the pathogenesis of anemia associated with lymphoma. Methods: Bone marrow (BM) erythroid cell (CD71+, GPA+) apoptosis (annexin V) and proliferation (Ki-67) were measured by flow cytometry in lymphoma patients and normal donors. Results: BM CD71+ and GPA+ cells showed a significantly greater proportion of apoptotic cells in lymphoma than in normal samples. Proliferation rate was also significantly increased in lymphoma BM CD71+ and GPA+ cells than in normal samples. Conclusion: Increased apoptosis in lymphoma BM erythroid cells may contribute to the anemia characteristic of this disorder. Proliferation might be up-regulated on BM erythroid cells via negative feedback loop resulting from a state of apoptosis.