The Study Of Expression Of Cysteine-Rich 61 And Its Significances In Patients With Acute Leukemia

Objectives: Leukemia is the most common malignant tumor in the blood system with poor prognosis and low survival rate. The study of abnormal angiogenesis of tumor may be of great value in understanding the nature of leukemia formation and evolution, and may be of great help in diagnosis and improving the prognosis of leukemia. CYR61 (cysteine rich 61) (also to call blood vessel induce generate factor) is one of the CNN family members ,a immmediately-early gene expressed abundantly in various tumors.Cell-proliferation and tumor- migation of CYR61 over-expression has been demonstrated in experiments in vitro and in-vivo. Results of study in digestive system neoplasms and breast cancer suggested that it may participate in tumorigeness, angiogenesis and late tumor invasion, and may influence on patients' prognosis. It was speculated that the overexpression of CYR61 may be a common and important event in tumor formation and developmention including leukemia.But, so far, there were still no research reports about the expression of CYR61 in leukemia patients. We explore the correlation between overexpression of CYR61 and abnormal expression of VEGF in AL ( acute leukemia), and chemotherapy outcome prognostic factors,and extramedullary infiltration of AL. The study will provide a theoretic basis to investigate deeply the role of CYR61 in leukemia pathogenesis.Materials and Methods: 1.Study objectTo select 48 newly diagnosed patients with AL of receiving hospitalization and 10 healthy person from June 2007 to April 2008 in department of Hematology, Qilu Hospital ,Shandong University. 48 AL patients include 26 males and 22 females, median age is 40 years old(17-65).All patients were parted by different standards:①28 acute myelocytic leukemia (AMD patients,20 acute lymphoid leukemia (ALL) patients.②22 extramedullary infiltration patients,26 nonextramedullary infiltration patients.2. MethodsExpressions of CYR61 and VEGF mRNA were detected in bone marrow mononuclear cell( BMMNC) from 48 cases of untreated acute leukemia patients and 10 normal controls by reverse transcriptase-polymerase chain reaction(RT-PCR). Expressions of CYR61 and VEGF protein were detected by immunocytochemical staining method analysis in above AL and normal controls.3. StatisticsAll datas were analyzed by statistical software SPSS13.0. Median, (X|-)±SD andpercentage were used to demonstrate datas. To compare two medians of two groups use T-test. To compare Multi-x group use analysis of variance. Multi-variables usemultielement stepwise regression to analyze. Enumeration datas use x~2 test,α= 0.05 issignificant level. The standard of test in statistical significent defference is p <0.05(double sides).Results:1 .Reverse transcriptase-polymerase chain reaction(RT-PCR) showed that:(1)A positive rate of CYR61 and VEGF gene in (acute leukemia) AL patients were significantly higher than that of the controls (p <0.05). The expression levels of CYR61 and VEGF showed positive correlation (r= 0.2718,p<0.05).(2)The overexpressions of CYR61 and VEGF gene were found in AML and ALL (P<0.05); There is no significant diference in the expression of CYR61 and VEGF gene in diferent subtype of AML (p >0.05). (3)The expressions of CYR61 and VEGF gene in pretreated patients who obtained complete remission after chemotherapy were lower than patients who failed to get remission(p <0.05).(4)The expressions of CYR61 and VEGF gene in the patients with extramedullary infiltration were higher than in the patients without extramedullary infiltration (p <0.05).(5)The expressions of CYR61 gene were significantly positive correlated with the number of blast cells in the bone marrow (r=0.3961, p <0.05),the expressions of VEGF gene(r=0.2718, P<0.01),the number of peripheral WBC(r=0.2319, p <0.05); and negative correlated with the number of platelets( r=-0.3723, p <0.05) in pretreated patients;The expressions of VEGF gene were significantly positive correlated with the number of blast cell in the bone marrow (r=0.3571, p <0.05),the number of peripheral WBC (r=0.2116, p <0.05); and negative correlated with the number of platelets (r=-0.4534, p <0.05)in pretreated patients. 2.Immunocytochemical staining method analysis showed that:(1)The expressions of CYR61 gene were mainly located in cytoplasm, and little of it was found in karyon. VEGF gene chiefly experssed in cytoplasm, little of it was found in karyon.(to see attached diagram).(2)The expression level of CYR61 was 87.5% (42/48 )in AL patients. It was significantly higher than the rate of 40%(4/10, p <0.05)in controls; The expression level of VEGF was 75 % (36/48 )in AL patients. It was significantly higher than the rate of 20%(2/10, p <0.05)in controls.(3) The expressions of CYR61 were closely correlated with VEGF in AL(x~2=4.406, p<0.05).(4) The expressions of CYR61 were closely correlated with the number of peripheral WBC,the number of hemoglobin and the number of blast cells in the bone marrow in AL patients.(p=0.036, p =0.012, p =0.005).Conclusion: 1 .There exists obvious overexpression of CYR61 and VEGF in patients with AL. Theexperssion levels of CYR61 and VEGF were negative correlated with effects ofchemotherapy in the AL patients. They could be used as helpful markers to observetherapeutic efficacy and to judge prognosis.2. The expressions of CYR61 and VEGF were positively correlated with thepercentages of primitive bone marrow cells. They might be correlated with tumorload.3.The overexpressions of CYR61 and VEGF in AL patients indicated that they maybepaticipate in the pathogenesis and progressionof acute leukemia. It can be a noveltarget for AL biological treatment.4. The high expressions of CYR61 and VEGF in AL might be correlate with infiltration of acute leukemic cell.5. The expressions of CYR61 are closed with the expressions of VEGF. It can be deduced that CYR61 affected tumor angiogenesis though regulating the expression of VEGF.