Expression Of Tim-3 In Acute Leukemia And Its Significance

PARTⅠ Tim-3 expression in acute leukemia cells and clinic characteristics【Objective】To explore the role of Tim-3 in patients with de novo acute leukemia and the correlation between Tim-3 and clinicopathological prognosis.【Methods】The study population consisted of 135 consecutive patients at the First Affiliated Hospital of Soochow University between January 2015 and August 2015.Tim-3 expressing on blast was analyzed by flow cytometry.The relationships between Tim-3 expression and characteristics of patients were analyzed.【Results】1. According to FAB type, 90 AML patients were diagnosed as M0(n=2), M1(n=16),M2(n=20), M3(n=14), M4(n=20), M5(n=16) and M6(n=2), respectively. According to the2013 NCCN guidelines, all the de novo non-M3 AML patients were divided into 3 groups,including 16 cases with low risk group, 38 cases with intermediate risk group, 18 cases with high risk group. And the ALL group consisted of 38 cases with B-cell ALL and 7cases with T-cell ALL, including 16 cases with high risk group and 27 cases of standard risk group.2. The expression level of Tim-3 in non-M3 AML was 58.26±29.23(4).Tim-3was not expressed on blast cells in all M3 cases. Tim-3 expression was significantly increased in M4 patients than in other patients according FAB type(P<0.05). The expression level of Tim-3 in low risk group, intermediate and high risk groups were74.63±24.24(4) 、 50.55±27.72(4) 、 54.72±26.88(4) respectively. High level of Tim-3expression was found in low risk group than in intermediate and high risk group(P<0.05),whereas no significant difference between intermediate and high risk groups(P>0.05). The expression level of Tim-3 in ALL patients was 29.70±23.79(4), while Tim-3 expression significantly increased in the T-ALL group than in the B-ALL group(P<0.05).There was no significant difference between high risk group and standard risk group(P>0.05).3.Tim-3 high expression was also closely associated with inv(16)(P<0.05) and C/EBPA mutation(P<0.05). The expression level of Tim-3 on blast cells was positively correlated with CD13(in AML group, r=0.33, P=0.02; in ALL group, r=0.35, P=0.03), and with CD34(in AML group, r=0.51, P=0.00; in ALL group, r=0.34, P=0.04).4.Tim-3 expression was not significantly associated with potential prognostic factors, including age or cytogenetic risk in ALL patients. AML patients with high Tim-3 expression achieved significantly high complete remission(CR) rate(P<0.05) and then their Tim-3 expression significantly decreased after CR(P<0.05), but such trend did not occur in ALL patients.【Conclusion】Tim-3 is highly expressed in non-M3 AML and T-ALL patients. Tim-3 expression might be associated with clinical characteristics and response to induction chemotherapy in de novo non-M3 AML.PARTⅡ Tim-3 expression in acute leukemia cells and preliminary study of its mechanism【Objective】To investigate Tim-3 expression in different types of acute leukemia cell lines and patients with acute leukemia, and to explore the preliminary study of its mechanism.【Methods】The study consisted of 8 kinds of acute leukemia call lines, 55 acute leukemia patients and 15 healthy donors.Tim-3 m RNA expression was analyzed by real-time quantitative PCR(RT-q PCR). Due to high expression of Tim-3, Kasumi-1 cell line was chosen for in vitro experiment. Cell proliferation was detected the intervention of the compound after blocking Tim-3 expression.We also detected the effect of Tim-3 inhibition on the m RNA expression of TNF-α、p65 and PPARγ by RT-q PCR after interruption of Tim-3 expression with anti-Tim-3 block antibody.【Results】1.The expression level of Tim-3 in NB4、Kasumi-1、HL60、SHI-1、CCRF-CEM、THP-1、Jurkat、Mutz-1 cell lines were(4.51?0.62)×10-5、(79.22?2.91)×10-5、(41.14?3.01)×10-5、(27.70?3.50)×10-5、(42.80?2.95)×10-5、(60.47?4.97)×10-5、(10.44?1.77)×10-5、(11.68?1.96)×10-5 respectively. The expression of Tim-3 m RNA were higher in non-M3(Kasumi-1、HL60、Jurkat etc) cell lines than M3(NB4) cell line.2.The relative expression of Tim-3 m RNA in non-M3 acute myeloid leukemia(AML) group, M3 group and acute lymphoblastic leukemia(ALL) group were(27.64?13.35)×10-4,(4.81?2.30)×10-4,(32.09?23.42)×10-4 respectively.Tim-3 m RNA expression was increased in non-M3 AML group and ALL group than in healthy control group(P<0.05), but no significant difference was found between non-M3 AML and ALL groups(P>0.05).Tim-3 expression was significantly increased in M4 patients than in other non-M3 AML patients according to FAB type(P<0.05). 3. Compared with control, the compound increased cell proliferation in a low concentration after blocking Tim-3 expression(P<0.05). Interruption of Tim-3expression was associated with the decrease of TNF-α、p65 m RNA expression and with the increase of PPARγ m RNA expression(P<0.05).【Conclusion】Tim-3 gene is expressed on non-M3 acute leukemia and cell lines. High expression of Tim-3 might improve the killing activity of anti-tumor drugs, which may be related with the activation of NF-κB signaling pathway and the high expression of TNF-α.