TAp73 and ΔNp73 relative expression in Egyptian patients with lymphoid neoplasms.
OBJECTIVE
The p73 gene has different isoforms with opposing anti- and pro-apoptotic functions. The pro-apoptotic activities are inhibited by overexpression of the dominant ΔNp73 isoform. The aim of this study was to detect the expression of the TAp73 and ΔNp73 isoforms in Egyptian patients with malignant lymphoid neoplasms. Their expression was analyzed by quantitative RT-PCR.


METHODS
The study included 30 B-NHL patients, 24 T-NHL patients, 16 ALL patients, 18 CLL patients, 22 patients with reactive lymphoid hyperplasia, and 6 healthy control subjects.


RESULTS
ALL and CLL patients expressed both isoforms at higher levels compared to lymphoma patients. Higher expression of TAp73 was found in both B-NHL and T-NHL (around 4-fold and 16-fold, respectively) in comparison to ΔNp73 (2-fold and 14-fold, respectively). In CLL patients both isoforms showed higher expression levels in comparison to normal peripheral blood lymphocytes controls: nearly 27-fold for TAp73 and 233-fold for ΔNp73. All ALL patients showed higher expression of both studied isoforms than controls (9-fold for TAp73 and 386-fold for ΔNp73). The highest ΔNp73 expression along with a higher ΔNp73/TAp73 ratio (67-fold) was found in ALL patients compared with CLL patients (21-fold).


CONCLUSIONS
A considerable number of lymphoma patients lacked the expression of either or both isoforms, while all lymphoid leukemia patients expressed both isoforms. The expression pattern differences of p73 isoforms may reflect differences in the biology of these malignancies.
Department of Clinical and Chemical Pathology, Faculty of Medicine, Cairo University, Cairo - Egypt.
Mona Salah Al-Din
MSA
Hamdy
Department of Clinical and Chemical Pathology, Faculty of Medicine, Cairo University, Cairo - Egypt.
Zainab Ali
ZA
El-Saadany
Department of Clinical and Chemical Pathology, Faculty of Medicine, Cairo University, Cairo - Egypt.
Manal Mohamed
MM
Makhlouf
Department of Pathology, National Cancer Institute, Cairo University, Cairo - Egypt.
Asmaa Ibrahim
AI
Salama
Department of Clinical and Chemical Pathology, Faculty of Medicine, Cairo University, Cairo - Egypt.
Nihal Salah
NS
Ibrahim
Department of Clinical and Chemical Pathology, Faculty of Medicine, Cairo University, Cairo - Egypt.
Alaa Amr
AA
Gad
D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell; D016403:Lymphoma, Large B-Cell, Diffuse / Q000235:genetics* / Q000473:pathology; D008228:Lymphoma, Non-Hodgkin / Q000235:genetics* / Q000473:pathology; D008297:Male; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics* / Q000473:pathology; D020033:Protein Isoforms / Q000096:biosynthesis / Q000235:genetics; D000072160:Tumor Protein p73 / Q000096:biosynthesis* / Q000235:genetics
D020033:Protein Isoforms; D000072160:Tumor Protein p73