| Chronic myeloid leukemia is a malignant and proliferating disease originating from multipotent hemopoietic stem cell. It is characterized by a specific chromosomal translocation, t(9;22), that resulting in a shortened chromosome 22, commonly referred to as the Philadelphia (Ph) chromosome. Ph chromosome is a translocation of the distal deleted segment of 22q to the distal portion of 9 q, forming bcr/abl fusion gene. The bcr/abl fusion gene express P210bcr/abl, P190bcr/abl or P230bcr/abl protein with tyrosinkinase activity, which is the pathogenesis of chronic myeloid leukemia. But the Ph chromosome is not a only cytogenetics abnormality in chronic myeloid leukemia. There are also other variant translocations and extra chromosomal abnormalities. STI571 can specificly inhibit tyrosine kinase activity of p210bcr/abl and p190bcr/abl and targeted therapy chronic myeloid leukemia. But STI571 can not eradicate the malignant clone of chronic myeloid leukemia. STI571 treat some patient of chronic myeloid leukemia can not be obtained the satisfied result. With time pass, some patients of chronic myeloid leukemia treated with STI571 appear to resiste STI571. So to search the new and effective scheme for increasing the therapeutic effect , to overcome the resistance to STI571 and eradicate the malignant clone of chronic myeloid leukemia are the research hot spot of treating chronic myeloid leukemia. This research can be divited into two parts. The first part is cytogenetic research ofchronic myeloid leukemia. The second part is the research of STI571 in combination with chemotherapeutic medicine effecting K562 cell line.PART ONECytogenetic research of chronic myeloid leukemiaa. Cytogenetics analysis of chronic myelogenous leukemia in 25 cases of complex variant chromosome translocationObjective To report 25 cases with chronic myelogenous leukemia of complex variant chromosome translocation and to analyze these cytogenetic date Method Bone marrow direct method and/or short-term culture were used to prepare the chromosomes and karyotype was performed with R-banding technique .bcr/abl fusion gene detection was performed with PT-PCR method. Result The overall frequency of complex variant chromosome translocation (based on 1209 cases of chromosome detection with chronic myelogenous leukemia) is 2.07%. It includes 22 cases of chronic myelogenous leukemia in blastic phage, 3 cases in chronic phage .Among 25 cases, 17 cases have complex variant chromosome translocation only involved 3 chromosomes, the others have otherchromosome abnormalities, including ph, +9, +19> +2U -18, -2K -y > der (6), der (9), der (22), del (11), t (17;22) etc. Apart from complex variant chromosome translocation. This group of 25 cases with complex variant chromosome translocation are involved in chromosome 1(4 cases), 3(2 cases), 4(1 case), 6(3 cases), 7(5 cases), 8(1 case), 11(3 cases), 12(2 cases), 14(1 case), 17(3 cases), 19(1 case) besides chromosome 9 and 22. 6 cases ware detected with bcr/abl fusion gene Conclusion The overall frequency of complex variant chromosome translocation (based on 1209 cases of chromosome detection with chronic myelogenous leukemia) is 2. 07%. Among 25 cases, 24 cases of complex variant chromosome translocation are involved in both the chromosome 9 and the chromosome 22;1 case is involved in the chromosome 22. The type of bcr/abl fusion gene in 6 cases detected with bcr/abl fusion gene is positive.4 cases is type b3a2 and 2 cases is type b2a2. It is worth to investigate whether there are other types of bcr/abl fusion gene in these 25 cases complex variant chromosome translocation apart from b3a2 and b2a2.b. Report of 12 cases of chronic myeloid leukemia with isochromosome 17qObjective To report 12 cases of isochromosome 17q with chronic myeloid leukemia Method Bone marrow direct method and/or short-term culture were used to prepare the chromosomes and karyotype was performed with R-banding technique Result The overall frequency of isochromosome 17q (based on 1209 cases of chromosome detection with chronic myeloid leukemia) is 0.99%. It includes 6 cases of chronic phage, 4 cases of accelerated phage and 2 cases of blastic phage with chronic myeloid leukemia. The frequency of them are 6/12 (50%) in chronic phage, 4/12(33%) in accelerated phage and 2/12 (16%) in blastic phage among 12 cases of isochromosome 17q with chronic myeloid leukemia. Apart from sole i( 17q ) , t(9;22)(q34;qll) abnormalities in 5 cases of 12 cases of isochromosome 17q with chronic myeloid leukemia, the other 8 cases have other abnormalities. The other abnormalities include +ph,+8 etc. Conclusion The overall frequency of isochromosome 17q (based on 1209 cases of chromosome detection with chronic myeloid leukemia) is 0. 99%. It includes 6 cases of chronic phage, 4 cases of accelerated phage and 2 cases of blastic phage with chronic myeloid leukemia. The frequency of them are 6/12 (50%) in chronic phage, 4/12 (33%) in accelerated phage and 2/12(16%) in blastic phage among 12 cases of isochromosome 17q with chronic myeloid leukemia. Apart from sole i (17q), t (9;22) (q34;qll) abnormalities in 5 cases of 12 cases of isochromosome 17q with chronic myeloid leukemia, the other 8 cases have other abnormalities. The other abnormalities include +ph, +8 etc. The functional significance of an i (17q) is unclear. The significance of i (17q) in the development of blastic crisis also remains uncertain.c. Report of 16 cases of chronic myeloid leukemia with trisomy 8Objective To report 17 cases of trisomy 8 with chronic myeloid leukemia Method Bone marrow direct method and/or short-term culture were used to prepare the chromosomes and karyotype was performed with R-banding technique Result The overall frequency of trisomy 8 (based on 1210 cases of chromosome detection with chronic myeloid leukemia) is 1. 40%. It includes 8 cases of chronic phage, 6 cases of accelerated phage and 3 casesof blastic phage with chronic myeloid leukemia. The frequency of them are 47% (8/17) in chronic phage, 35% (6/17) in accelerated phage and 18%(3/17) in blastic phage among 17 cases of +8 with chronic myeloid leukemia. Apart from sole +8, t(9;22) (q34;qll) abnormalities in 3 cases of 17 cases of +8 with chronic myeloid leukemia, the other 14 cases have other abnormalities. The other abnormalities include +ph, i (17q), +21 etc. Conclusion The overall frequency of trisomy 8 (based on 1210 cases of chromosome detection with chronic myeloid leukemia) is 1. 40%. It includes 8 cases of chronic phage, 6 cases of accelerated phage and 3 cases of blastic phage with chronic myeloid leukemia. The frequency of them are 47%(8/17) chronic phage, 35% (6/17) in accelerated phage and 18% (3/17) in blastic phage among 17 cases of +8 with chronic myeloid leukemia. Apart from sole +8, t(9;22)(q34;qll) abnormalities in 3 cases of 17 cases of +8 with chronic myeloid leukemia, the other 14 cases have other abnormalities. The other abnormalities include +ph, i(17q), +21 etc.PART TWOResearch of STI571 in combination with chemotherapeutic medicine effecting K562 cell lineObjective To research whether STI571 in combination withhomoharringtonine or cytosine arabinoside have synergistic effect for proliferation and apoptosis of K562 cell line .To research whether STI571 in combination with homoharringtonine or cytosine arabinoside have synergistic effect for bcr/abl fusion gene. Method The experimental groups are divided into following groups: STI571 group, homoharringto-nine group, cytosine arabinoside group, the group of STI571 in combination with homoharringtonine and the group of STI571 in combination with cytosine arabinoside. We perform the MTT method to detecte inhibition ratio of cell proliferation of K562 cell line after using each group of experimental medicine, observe apoptosis using the cell morphology of K562 cell line after using each group of experimental medicine and perform the Annexin V-PI to detect apoptostic ratio of K562 cell line after using each group of experimental medicine. We also perform real-time quantitative PCR to detecte levels of bcr/abl mRNA of K562 cell line after using each group experimental medicine. Result The inhibition ratio of cell proliferation of STI571 group, homoharringtonine group, cytosine arabinoside group, the group of STI571 in combination with homoharringtonine and the group of STI571 in combination with cytosine arabinoside are 11.00 + 5.19%, 21.66 + 2.96% ,15.00 + 4.35% 23. 33±2. 60% and 17.33 + 6.06% respectively after using each experimental groups to effect K562 eel line in 8 hours, each group heve typical cell apoptosis after using eachexperimental groups to effect K562 eel line in 8 hours. The early phase cell apoptosistic ratios of STI571 group, homoharringtonine group, cytosine arabinoside group, the group of STI571 in combination with homoharringtonine and the group of STI571 in combination with cytosine arabinoside are 3. 06%, 5. 44% , 2. 49%, 13. 44% and 4. 49%(control: 0. 53%) respectively after using each experimental groups to effect K562eel line in 8 hours. The advanced phase cell apoptostic ratios of STI571 group, homoharringtonine group, cytosine arabinoside group, the group of STI571 in combination with homoharringtonine and the group of STI571 in combination with cytosine arabinoside are 1.15%, 2.95%, 2.69%, 8. 49% and 2. 45% (control: 1.13%) respectively. The bcr/abl m RNA levels of STI571 group, homoharringtonine group, cytosine arabinoside group, the group of STI571 in combination with homoharringtonine and the group of STI571 in combination with cytosine arabinoside are 46. 96%, 45.67%, 44. 52%, 23. 73% and 36. 20% (control: 68. 54%) respectively. Conclusion STI571 in combination with homohar-ringtonine has stronger synergistic effect for inducing cell apopto-sis. STI571in combination with cytosine arabinoside has not significant synergistic effect for inducing cell apoptosis. Compared with STI571 in combination with homoharringtonine or STI571 in combination with cytosine arabinoside for inhibiting cell proliferation and induc-ing cell apoptosis , inducing cell apoptosis is the main effect other than inhibiting cell proliferation. STI571 in combination with homoh-arringtonine has more distinct synergistic effect for decreasing bcr/abl m RNA level of K562 cell line. STI571 in combination with cytosine arab-inoside has some synergistic effect for decreasing bcr/abl m RNA level of K562 cell line.
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