Presence of simian virus 40 DNA sequences in egyptian patients with lymphoproliferative disorders.

BACKGROUND Although no definite risk factors have emerged for the different hematological malignancies, a viral cause has been postulated. Several studies have detected SV40 DNA sequences in tumor tissues obtained from non-Hodgkin's lymphoma patients. A link between SV40 and NHL is biologically plausible because SV40 causes hematological malignancies in laboratory rodents. METHODS We investigated 266 Egyptian cases of different hematological malignancies, for the presence of SV40 DNA using multiplex nested PCR technique. These cases consisted of 158 non-Hodgkin's lymphoma (NHL), 54 Hodgkin's disease(HD), 26 acute lymphocytic leukemia (ALL), 13 acute myeloid leukemia (AML), 8 chronic lymphoblastic leukemia (CLL), 7 chronic myeloid leukemia (CML), in addition to 34 subjects of control group. RESULTS Our results have shown that SV40 DNA sequences were found in 53.8% of non-Hodgkin lymphoma patients, 29.6% of Hodgkin's disease patients, and 40.7% of different types of leukemia cases. Frequency of SV40 DNA sequences was higher in NHL patients compared to the other tumor cases. Also, frequency of SV40 DNA sequences was significantly higher (p<0.05) in NHL patients than in the control group. Regarding the different histological types of non-Hodgkin's lymphoma, SV40 DNA sequences were detected frequently in diffuse large B-cell lymphoma and in follicular lymphoma. CONCLUSIONS The present study suggests that SV40 DNA virus is significantly associated with non-Hodgkin's lymphoma and might have a role in the development of these hematological malignancies. Polyomavirus SV40 may act as a cofactor in the pathogenesis of these tumors and this could lead to new diagnostic, therapeutic, and preventive approaches.