| Background and ObjectiveAcute myeloid leukemia (AML) is a heterogeneous disorder characterized by aberrant proliferation and differentiation of the malignant cells. Factors contributing to the loss of responsiveness to normal growth controls exhibited by the leukemic clone include factor independent activation of signal transduction pathways critical to normal cell proliferation and survival. Integrin-linked kinase (ILK) is an ankyrin-repeat containing serine/threonine kinase involved in both cell interactions with the extracellular matrix and regulation of cell growth and survival, cell-cycle progression, epithelialm esenchymal transition, invasion, migration, and tumor angiogenesis, ILK activates a range of signaling pathways. ILK is avtivated in the phosphatidylinositol-3-kinase (P13K)-dependent pathway, The expression and activity of ILK are increased in a variety of solid tumors. ILK, in combination with Rictor promotes cell survival by stimulating phosphorylation of protein kinase B/Akt on ser473, a necessary step for maximal Akt activation. In addition, small molecule inhibitors of ILK activity have been identified and shown to inhibit tumor growth, invasion, and angiogenesis. Therefore, ILK is identified as a potential therapeutic target of a number solid tumor. However, little was known about expression and activation of ILK and ILK/Akt pathway in human AL or how such expression and activation might contribute to the signaling abnormalities that have been observed in leukemic blasts. In present study, ILK and Akt-mRNA expression in bone marrow mononuclear cells from patient with acute leukemia was detected by RT-PCR, and the correlation beween the expression level of ILK and Akt was evaluated. At the same time, explore the possible effects of ILK/Akt pathway in acute leukemia.Material and methods1. Research objectives:(1) De novo leukemia group: Samples from 48 cases of de novo Acute Leukemia were collected. Patients were 17-66 years (median 39 years old) with 21 males and 27 females. Patients were divided into two groups:Acute Myeloid Leukemia (AML) (n=31), including M2 18 cases, M3 6 cases, M5 7 cases; Acute Lymphoblastic Leukemia (ALL)(n=17):including B-ALL 10 cases and T-ALL 7 cases. (2)Relapsed patients (n=9):this group included 5 males and 4 females with a median age of 40(16 to 64) years. (3)AL-CR group(n=11):bone marrow samples form 11 patients who reached CR after chemotherapy. (4)The control group(n=10):bone marrow samples from non-malignant hematologic diseses or HSCT donors. All patients were enrolled for the research, who hospitalized in the Department of Hematology of the First Affliated Hopsital of ZhengZhou Univesrity from April to September,2010. The diagnosis of acute leukemia is made based on complete blood count, bone marrow morphology, cytochemistry, cytogenetic and immunophenotype, according to the criteria for diagnosis of acute leukemia.2. Method:This experiment uses RT-PCR to detect the ILK and Akt mRNA in bone marrow mononuclear cells (BMMNCs). BMMNCs were separated from bone marrow, total RNAs were extracted by TRIZOL, then reverse transcripted to cDNA, and PCR were performed in the primers of the ILK and Akt mRNA. The products of PCR were electrophoresed in agarose gel, the bands were visualized by UV light and the optic density of each band was measured. The ratios of ILK and Akt mRNA/β-action mRNA were evaluated.3. Statistical analysis:The data were analyzed using Software SPSS 17.0. Quantitative data were expressed as mean±standard deviation (x±SD); Paired means were analyzed by Independent-Samples t test, while Various means were analyzed by variance analysis. Qualitative data were analyzed by chi-square test; The standard of significant level was a=0.05.Results1. Expression of ILK mRNA in Acute LeukemiaThe expression rate of ILK mRNA in Do nove AL was 72.9%,6 patients that relapsed out of 9 (66.7%) expressed ILK mRNA and ILK mRNA also expressed in 4 out of 11 AL-CR patients (36.4%), the average expression levels of three groups were 0.689±0.181,0.628±0.203 and 0.329±0.092 respectively; the positive rate of control group was 20.0%.77.4% of Do nove AML patients expressed ILK mRNA, a little higher than it's counterpart of ALL, which was 64.7%, the average expression level of these two groups were 0.710±0.193 and 0.641±0.151, however, the differences between the later two groups were not statistically significant(p>0.05). The positive rate of Do nove group was higher than that of AL-CR group and control group, the difference was statistically significant(p<0.05). The difference between Do nove group and recurrent group was not statistically significant whether in positive rate or in average expression level(p>0.05). Interestingly, the difference between AL-CR group and recurrent group's average expression levels were statistically significant, however, there was no statistical significance between their positive rate(p>0.05).2. Expression of Akt mRNA in Acute Leukemia29 out of 48 Do nove AL expressed Akt mRNA, ratio was 60.8%, the average expression level of this group was 0.593±0.192; among this group,58.1%(18/31) AML and 64.7%(11/17) ALL expressed Akt mRNA, there average expression levels were 0.625±0.225 and 0.541±0.112 respectively; however, the later two groups' difference was not statistically significant(p>0.05). The expression rate of control group and AL-CR group were 10% and 27.3% respectively, which were lower than Do nove group(p<0.05).44.5% patients that relapsed expressed Akt mRNA,the average expression level was 0.479±0.010, the positive rate between recurrent group and AL-CR group has no statistically significance, however(p>0.05), the difference between their average expression levels was statically significant(p<0.05)3. There was a positive correlation between ILK and Akt expression in Do nove AL group(r=0.369,p<0.05).4. There was no significant relationship between ILK and Akt expression and clinical features(p>0.05).Conclusions1. The expression of ILK and Akt mRNA were abnormal expressed in acute leukemia.2. The expression of ILK and Akt mRNA in acute leukemia were positively correlated, ILK/Akt pathway may involved in the progression of acute leukemia and can be potential therapeutic target of acute leukemia. |
PDF Full Text Request