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Background and Purpose: DNA repair capacity enhancement is one of the causes of adult acute leukemia primary or secondary resistance. Non-homologous end joining (non-homologous end joining, NHEJ) plays a key role in the damage and repair of DNA double-strand breaks (DSB), DNA-PK is the most important protein factors involved in NHEJ repair by Ku70, Ku80 and DNA- PKcs (DNA-dependent protein kinase catalytic subunit), DNA-PKcs is the catalytic subunit of three subunits. DNA-PKcs put in the tumor chemosensitivity aspect controversial, emerging high expression of DNA-PKcs tumor of radiotherapy and chemotherapy resistant and non-resistant to view. Few reports on DNA-PKcs study in adult patients with acute leukemia, DNA-PKcs expression levels can be used as indicators that further studies were needed to predict acute leukemia. Therefore, the study of adult acute leukemia bone marrow mononuclear cells in the expression levels of DNA-PKcs detection and analysis of its clinical features, clinical efficacy and chromosomal abnormalities relationship, to explore NHEJ significance of this major repair pathways in acute leukemia . Methods: 105 patients with newly diagnosed acute leukemia patients before chemotherapy and in 41 cases two course DNA-PKcs expression in bone marrow mononuclear cells after chemotherapy, in order to analyze the relationship between the clinical features, clinical efficacy using indirect immunofluorescence. R-banding karyotype detected 26 cases of newly diagnosed leukemia patients, and to analyze its relationship with the expression of DNA-PKcs. SPSS16.0 statistical software, data, chi-square test, Fisher exact test, rank conversion of non-parametric tests and signed rank test for paired samples, P lt; 0.05 difference was statistically significant. Results: 1.DNA-PKcs and clinical characteristics of DNA-PKcs in 105 previously untreated patients with leukemia patients total positive rate was 53.3%, DNA-PKcs expression in age, gender, average hemoglobin level, mean platelet count, bone marrow leukemic cells the proportion of the clinical classification level there was no significant difference (P = 0.891, P = 0.411, P = 0.240, P = 0.052, P = 0.376, P = 0.261). DNA-PKcs-positive group, 30.4% (17/56) in patients with newly diagnosed white blood cell count greater than 100 × 10 ^ 9/1, compared with the negative group, 10.2% (5/49), the difference was statistically significant (P = 0.011) . Expression levels and efficacy 2.DNA-PKcs relationship in 62 patients, and 33 patients without remission, remission group, 29 cases. Two groups before chemotherapy, DNA-PKcs in positive and strong positive (~) expression rates were 69.7% (23/33) and 37.9% (11/29) (P = 0.012), the difference was statistically significant. 41 cases after two cycles of chemotherapy without remission group and remission group DNA-PKcs positive and strongly positive (~) the expression rate accounted for 73.7% (14/19) and 40.9% (9/22), (P = 0.035), The difference was statistically significant. 41 patients before and after chemotherapy own line paired rank sum test, the change in fluorescence intensity of DNA-PKcs difference was not statistically significant (Z = -0.551, P = -0.593) DNA-PKcs expression of the relationship between the level of the chromosome 26 previously untreated patients with acute leukemia patients, chromosomal abnormalities in 10 cases, accounting for 38.5%, abnormal karyotype t (15; 17) (q22; q21) in two cases, the remaining abnormal karyotype del (7p), t (9; 22) (q34 ; q11); t (9; 22) (q34; q11), der (13), -20; -3; 22;-Y, t (8; 21) (q22; q22); 7q-?, mar; chromosome the 9q-; 6, 12/7, 12 one each, DNA-PKcs group of chromosomal abnormalities in the positive and strong positive (~) expression rate of 70% (7/10), significantly higher than the level of 25% of the normal group (4 / 16), (P = 0.032). Conclusion: 1. DNA-PKcs expression in adult acute leukemia in newly diagnosed increased white blood cell count. The 2.DNA-PKcs expression with age, gender, the proportion of myeloid leukemia cells, clinical type, mean hemoglobin level, mean platelet count level is no obvious correlation 3.DNA-PKcs protein levels in patients with acute leukemia, chromosomal abnormalities have a certain correlation.
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