الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 88 |  |  |
| | | from | 88 | | |
Abstract
B-CLL is a malignant lymphoproliferative disorder of mature B lymphocytes. It is characterized by the progressive accumulation of small mature-appearing, functionally incompetent, long-lived CD5+ lymphocytes in blood, bone marrow, lymph nodes, spleen, liver or other lymphoid tissues.
During the last few years there was a continuous effort to identify novel prognostic factors in B-CLL which may help define patient subgroups who may benefit from early therapeutic intervention. In the context of these efforts, the determination of the IgVH mutational status is recognized now as a significant prognostic marker which is independent on the classical staging of disease. As the costs of this test are fairly high and the availability of this molecular testing is still limited to the large research laboratories, there is a sustained long-term effort to identify the prognostically relevant parameters without these limitations. Surface and/or intracellular molecules which can be easily measured by flow cytometry were investigated. Among these, ZAP-70 expression has emerged as potential surrogate markers for IgVH mutational status.
Also, it was shown that the level of hTERT expression discriminated the Ig-unmutated from Ig-mutated B-CLL and may serve as a molecular prognostic marker. Moreover, CLLU1 appears as a novel gene and disease specific marker. Albeit the function is unknown, CLLU1 expression might hold some prognostic information not offered by other biologic markers in B-CLL.
So, the aim of the current work was to study CLLU1, hTERT and ZAP-70 expression in B-CLL patients. Correlation of these parameters with each other and with the traditional staging systems was also studied.
The study design included clinical assessment, with special emphasis on lymph nodes, liver and spleen, routine hematological examinations, and immunophenotyping.
The current study was carried out on 30 B-CLL patients (16 males and 14 females), who were newly diagnosed and still untreated cases. Lymphoadenopathy was the most frequent presenting feature (76.7%), followed by splenomegaly (66.7%), while only (20%) patients presented with hepatomegaly. Anemic manifestations were present in (36.3%), while only (10%) of patients presented with bleeding.
Patients were stratified according to Binet staging system with 7 (23%) of B-CLL patients in stage A, 10 (33.3%) in stage B and 13 (43.7%) in stage C. In Binet stage A, 3 (43%) males and 4 (57%) females and in Binet stage B, 5 (50%) males and 5 (50%) females while in Binet stage C, 8 (61.5%) males and 5 (38.5%) females. Also, there were insignificant difference in age distribution in the different Binet stage groups (p=0.977)
PBMCs were isolated from B-CLL patients and ZAP-70 expression was detected using immunocytochemical staining technique performed on smears of PBMCs and QRT-PCR was performed for detection of hTERT and CLLU1 mRNA expression in PBMCs.
The results of our study can be summarized in the following points:
As regard Binet stage, Hb level and platelets were significantly lower with stage progression (P<0.001, p<0.001), respectively, while TLC was significantly higher with stage progression (p=0.014). But, the lymphocyte count was statistically non significant with stage progression (p=0.318).
Immunocytochemical staining of ZAP-70 in PBMCs was positive in 9 patients (30%), while 21 patients (70%) were negative for ZAP-70. The percentage of ZAP-70 positive cells was found to be associated with Binet stages, being significantly increased (P=0.007) with stage progression. The Hb level was significantly lower in patients with positive ZAP-70 (p=0.05), while, ZAP-70 expression was statistically non significant as regards TLC, the lymphocyte count and the platelet count
ZAP-70 expression in PBMCs was positively correlated with Binet stage, TLC and lymphocyte count (r=0.236, p= 0.006; r=0.466, P=0.01; r=0.491, p=0.006) respectively, while it correlated negatively with the Hb level and platelet count (r = -0.389, p = 0.034; r= -0.444, p =0.014) respectively.
The expression levels of hTERT mRNA were positive in all studied B-CLL cases ranging from to 0.01 to 104.26 expression units. The expression levels of hTERT mRNA were lower in Binet stage C patients but the difference was statistically non significant as regards clinical Binet stage (P= 0.655).
The expression levels of hTERT mRNA were higher in ZAP-70 positive patients than in ZAP-70 negative patients but the difference was statistically non significant (P=0.060).
The expression levels hTERT mRNA were not correlated with Binet stage, hematological parameters or ZAP-70.
The expression levels of CLLU1 mRNA were positive in all studied B-CLL cases, ranging from 0.03 to 95.49 expression units but completely undetermined in normal healthy cells. This indicates that it is specific for B-CLL. The expression levels of CLLU1 were increased in B and C (advanced) Binet stage compared with those at Binet stage A but the difference was non significant.
The expression levels of CLLU1 mRNA were higher in ZAP-70 positive patients than in ZAP-70 negative patients but the difference was statistically non significant.
The expression levels of CLLU1 mRNA were not correlated with Binet stage, hematological parameters, ZAP-70 or hTERT.