Distribution of Cytoskeleton Protein Nestin in Acute Leukemia.

Abstract Abstract 4721 Objective Nestin was detected in some tumor cells and nestin expression was positive relative with malignancy of glioma, angioma and melanoma. Nestin maybe was considered as marker of tumor malignancy and cell proliferation. There was no report about nestin expression in acute myeloid leukemia (AML) and acute lymphoblast leukemia (ALL). Herein, we describe the clinicopathological and immunohistochemical features of 48 patients with acute leukemia, introducing nestin as an additional marker that identifies these tumors .Meanwhile, Nestin and ki67 antigen expression were done to identify the relation of nestin and cell proliferation in AML, and the correlation between histoscore of nestin expression on leukemic blasts and patients' complete remission rate (CR) and overall survival (OS) was analyzed in AML. Methods Nestin and ki67 antigen expression in a series of 37 AML samples, 11 ALL samples, 2 multiple myeloma samples (MM) and 2 chronically myeloid leukemia samples (CML) were done with immunohistochemistry. Histoscore of nestin expression on leukemic blasts with AML and ALL was done and analyzed with independent t-test. The correlation of histoscore of nestin expression with patients' CR rate in AML was analyzed by the method of chi-square test. Patients' OS analysis was determined by the method of Kaplan and Meier, with log-rank analysis to estimate statistical significance in AML. P values of <0.05 were considered significant. Results Among 37 cases with AML, Nestin expression was observed in most leukemic blasts, and matural granulocytic cell also expressed nestin in 30 cases .The ratio of tumor cell expressing nestin and total tumor cells was over fifty percents in AML in 14 patients. The ratio of tumor cell expressing nestin and total tumor cells was over ten percents in AML in 7 patients. The ratio of tumor cell expressing nestin and total tumor cells was less ten percents in AML in 9 patients. Nestin expression was not observed in 8 patients. Where ki67 expressed in AML, nestin expressed intensely in 7 cases with AML. But other cases did not express ki67. However, histoscore of nestin expression on leukemic blasts in AML was not correlated with patients' CR (p=0.701) and OS (p=0.245). Nestin immune-reactivity in ALL mainly focused on matural granulocytic cells, matural lymphocytic cells and tumor cells did not express nestin. Compared with AML, there was significant statistical significance (p=0.007). Conclusions These findings constitute the first conclusive evidence that stem cell marker nestin expression in leukemic blasts with AML, CML, MM, but nestin did not express in leukemic blasts with ALL. Nestin may be a useful immunohistochemical marker for identifying AML and ALL. Nestin expression was not correlated with cell proliferation, patients' CR and OS in AML. Disclosures: No relevant conflicts of interest to declare.