A study of the relationship between expression level of TRF1 protein and telomerase activity in human acute leukemia

Objective： To study the expression level of TRF1 （telomeric repeat binding factor 1） protein in human acute leukemia and relationship between expression level of TRF1 protein and telomerase, Methods： A quantitative Western±Blot technique was developed using anti±TRF1^33±277 monoclonal antibody and GST±TRFI purity protein as a standard to further determine the expression level of TRF1 protein in total proteins extracted from clinical specimens. Results： Bone marrow tissues of 20 acute leukemia patients were studied, 11 healthy donors＇ bone marrows were taken as a control. The expression level of TRF1 protein was significantly higher （P〈0.01） in normal bone marrow （（2.2174±0.462） μg/μl） than that of acute leukemia patients （（0.7544±0.343） μg/μl）, But there was no remarkable difference between ALL and ANLL patients （（0.6184±0.285） μg/μl vs （0.8454±0.359） μg/μl, P〉0.05）. After chemotherapy, TRFI expression level of patients with complete remission elevated （（0.7724±0.307）/μg/μl vs （1.6834±0,344）μg/μl, P〈0.01 ）, but lower than that of normal （（2.2174±0.462）/μg/μl, P〈0.01）. There was no significantly difference after chemotherapy （（0.7264±0.411） μg/μl vs （0.895±0.339） μg/μl,p〉0.05）. TRF1 expression level of patients with complete remission is higher than that of patients without complete remission （（1,683±0.344）μg/μl vs （0.895±0.339）μg/μl P〈0.01）. All samples were determined for telomerase activity. It was confirmed that the activity of telomerase in normal bone marrow was lower than that of acute leukemia patients （（0.125±0.078） μg/μl vs （0.765±0.284）μg/μl, P〈0.01）. There was no significant difference of expression level ofTRF I protein between ALL and ANLL patients （（0.897±0.290） μg/μl vs （0.677±0.268） μg/μl, P〉0.05）. After chemotherapy, telomerase activity of patients with complete remission decreased （（0.393±0.125） μg/μl）, but was still higher than that of normal （（0.125±0.078） μg/μl, P〈0.01）. Conclusion： The expression level of TRF1 protein has correlativity to the activity of telomerase （P〈0.001）.

Objective: To study the expression level of TRF1 (telomeric repeat binding factor 1) protein in human acute leukemia and relationship between expression level of TRF1 protein and telomerase. Methods: A quantitative Western-Blot technique was developed using anti-TRF133-277 monoclonal antibody and GST-TRF1 purity protein as a standard to further determine the ex-pression level of TRF1 protein in total proteins extracted from clinical specimens. Results: Bone marrow tissues of 20 acute leukemia patients were studied, 11 healthy donors’ bone marrows were taken as a control. The expression level of TRF1 protein was significantly higher (P<0.01) in normal bone marrow ((2.217±0.462) μg/μl) than that of acute leukemia patients ((0.754±0.343) μg/μl). But there was no remarkable difference between ALL and ANLL patients ((0.618±0.285) μg/μl vs (0.845±0.359) μg/μl, P>0.05). After chemotherapy, TRF1 expression level of patients with complete remission elevated ((0.772±0.307) μg/μl vs (1.683±0.344) μg/μl, P<0.01), but lower than that of normal ((2.217±0.462) μg/μl, P<0.01). There was no significantly difference after chemotherapy ((0.726±0.411) μg/μl vs (0.895±0.339) μg/μl, P>0.05). TRF1 expression level of patients with complete remission is higher than that of patients without complete remission ((1.683±0.344) μg/μl vs (0.895±0.339) μg/μl, P<0.01). All samples were determined for telomerase activity. It was confirmed that the activity of telomerase in normal bone marrow was lower than that of acute leukemia patients ((0.125±0.078) μg/μl vs (0.765±0.284) μg/μl, P<0.01). There was no significant difference of expression level of TRF1 protein between ALL and ANLL patients ((0.897±0.290) μg/μl vs (0.677±0.268) μg/μl, P>0.05). After chemotherapy, telomerase activity of patients with complete remission decreased ((0.393±0.125) μg/μl), but was still higher than that of normal ((0.125±0.078) μg/μl, P<0.01). Conclusion: The expression level of TRF1 protein has corre-lativity to the activity of telomerase (P<0.001).