| Objective:To study the relationship between IK6 overexpression and clinical biological characteristics and long-term prognosis in children with acute B lymphoblastic leukemia.Methods:A total of 126 patients with acute B lymphoblastic leukemia were enrolled in our hospital from August 2008 to June 2015.Bone marrow specimens were collected at the initial diagnosis without chemotherapy,and the diagnostic models of MICM(morphology,immunology,cytogenetics,and molecular biology)were used,and the CCLG-ALL2008 protocol was used for risk grading and standard chemotherapy.Detection of IKZF1-IK6 expression in newly diagnosed bone marrow samples by PCR-GeneScan analysis.Analyse the clinical features of IK6 overexpression positive and negative groups in terms of gender,age,number of newly diagnosed white blood cells,karyotype,fusion gene status,MRD status,and final risk grouping,and evaluate the effect of IK6 overexpression on the survival rate and overall survival of children.Results:(1)Of the 126 children with B-ALL,61 were male and 65 were female,the ratio was 0.94:1,aged from 5 to 14 years,and the median age was 4.89(3.32,7.6)years.(2)Among 126 patients with B-ALL,there were 17 cases with IK6 positive,and the positive rate was 13.49%.According to whether IK6 was overexpressed,126 cases were divided into IK6+group and IK6-group.① The median age of the IK6+group was 5.70(3.99,9.40)years old,and the median age of the IK6-group was 4.89(2.89,7.47)years old.There was no significant difference in age between the two groups(U=692.5,P=0.171).There were 9 males(52.94%)and 8 females(47.06%)in the IK6+group,52 males(47.71%)and 57 females(52.29%)in the IK6-group.There was no significant difference in gender composition between the two groups 0(χ2=0.161,P=0.688).②IK6+group have a white blood cell count to 17.5(11.1,178.0)x 10 ^ 9/L,IK6-group have a number of white blood cells 14.87(4.77,49.57)x 10 ^ 9/L,white blood cell count at newly diagnosis between the two groups have statistical significance(U=531.5,P=0.039),prompted IK6 overexpression is associated with high white blood cell count.③ The BCR/ABL1 fusion gene was detected in 17 cases in the IK6+group(29.41%),and the BCR/ABL1 fusion gene was detected in 109 cases in the IK6-group(6.42%)..(χ2=6.55,P＝0.010).④There was no significant difference in chromosome typing(hyperdiploid,hypodiploid,pseudodiploid,normal karyotype)between the two groups(P=0.0The difference of BCR/ABL1 proportion between the two groups was statistically significant99,1.000,0.708,0.174).⑤The difference in sensitivity of hormone pretreatment between the two groups was statistically significant(χ2=8.33,P＝0.004).⑥There were 79 people test D15MRD,104 people test D33MRD.It was divided into low medium and high levels,according to<10-4,10-4～10-2>10,-2and the D15MRD level of the IK6+ group was significantly higher than that of the IK6-group,with a statistically significant difference(U＝362.0,P=0.048).The proportion of medium and high level D33MRD in the IK6+group was still higher than that in the IK6-group(50.00%vs44.32%,18.75%vs9.09%),but the difference was not statistically significant(U=577,P=0.144).⑦Among the 121 patients who received treatment and reached the treatment evaluation point,16 cases were in the IK6+group,including 7 cases in the high-risk group,5 cases in the middle risk group,and 4 cases in the standard risk group.There were 105 cases in the IK6-group,including 38 cases in the high-risk group,41 cases in the medium-risk group and 26 cases in the standard risk group.There was no statistically significant difference in risk distribution between the two groups(U＝793.5,P=0.704).(4)The relationship between overexpression of IK6 and prognosis.①122 B-ALL patients with standard treatment in our hospital were divided into IK6+group and IK6-group according to whether IK6 overexpression was found.The overall DFS rate between the two groups was 25.57%±19.38%vs55.47%±5.56%,respectively.χ2=0.6429,P=0.4204(P>0.05).The overall EFS rates between the two groups were 25.57%±19.38%vs51.76%±5.39%,respectively.χ2=0.199,P=0.6555(P>0.05).Overall OS rates between the two groups were 51.14%±13.95%vs49.45%±12.94%,respectively.χ2=1.058,P=0.3036(P>0.05).Compared with the overall DFS rate and overall EFS rate between the two groups,the IK6+group was lower than the IK6+group,and there was no significant difference in the overall OS rate,but the differences were not statistically significant.② According to the clinical risk group,the patients were divided into standard risk group and medium-high risk group,and the effect of IK6 overexpression in the group on the prognosis was compared.There was no statistical difference in DFS,EFS and OS between the positive and negative groups in the standard risk group.In the medium-high risk group,the overall DFS rate between the two groups was 0vs51.31%±6.59%,respectively.χ2=2.142,P=0.1433(P>0.05).The overall EFS rates between the two groups were 0vs46.49%±6.27%,respectively.χ2＝1.057,P=0.3040(P>0.05).The overall OS rate between the two groups was 33.33%±16.67%,vs62.48%±5.83%,respectively.χ2=2.453,P=0.1173(P>0.05).The DFS rate,EFS rate and OS rate between the two groups were lower in the positive group than in the negative group,but the differences were not statistically significant.Conclusion:1.IK6 overexpression occurs at a frequency of about 15.6%in children with acute lymphoblastic leukemia of B line,and is highly associated with BCR/ABL1 fusion gene.2.IK6+ is associated with high risk factors,like high initial white blood cell count,BCR/ABL1 positive,insensitivity to hormone preconditioning and high level of D33MRD,which may be one of the reasons for poor prognosis of children with this high risk factor.However,it is not clear whether it can be used as a risk stratification index alone.3.The overall relapse-free and event-free survival rates of patients with IK6 overexpression in this group were lower than those in the IK6-group,and the overall survival rates were similar,but the differences were not statistically significant.It suggests that the effect of IK6 overexpression on prognosis after intensive treatment needs further study. |
