title: Rituximab synergizes with hydroxyurea or vincristine in the killing of Ramos Burkitt's lymphoma B cell line.
abstract: Rituximab is an effective immunotherapy for CD20-positive B-cell non-Hodgkin's lymphoma. However, some patients show resistance, particularly those suffering from more aggressive lymphoma types, such as Burkitt's lymphoma. Hence, Rituximab is commonly combined with several chemotherapeutic drugs. With a view to reduce the number of such drugs, we examined the effect of combining Rituximab individually with hydroxyurea, vincristine, or etoposide on the killing of Ramos Burkitt lymphoma cell line type I. Cell death was examined by using Annexin-V/propidium iodide staining. Combining Rituximab with hydroxyurea or vincristine resulted in a synergistic effect, whereas combining it with etoposide resulted in a subadditive effect. In single treatments, the percentage of cell death ranged from 23% (Rituximab) to 36% (hydroxyurea). Combining Rituximab with hydroxyurea or vincristine resulted in a synergistic effect (83% and 74% killing, respectively). In contrast, only a subadditive effect was noticed with etoposide (36%). We conclude that the synergistic effect of Rituximab with hydroxyurea or vincristine is worthy of further study, and that further in vitro screening of chemotherapeutics might identify chemo-immunotherapeutic combinations that are effective in vivo but less toxic than currently used regimens.
authors.affiliation: 1 Cell Biology Research Group, Biotechnology Research Center , Twisha, Tripoli, Libya .
authors.forename: Mohamed
authors.initials: M
authors.lastname: Deyab
authors.forename: Abdulrhman
authors.initials: A
authors.lastname: Elbanani
authors.forename: Salah
authors.initials: S
authors.lastname: Tabal
authors.forename: Hajer
authors.initials: H
authors.lastname: Geriani
authors.forename: Yosra
authors.initials: Y
authors.lastname: Lamami
authors.forename: Amin
authors.initials: A
authors.lastname: Bredan
authors.forename: Abdulmunem
authors.initials: A
authors.lastname: Abulayha
mesh_terms: D058846:Antibodies, Monoclonal, Murine-Derived / Q000008:administration & dosage / Q000494:pharmacology; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D002051:Burkitt Lymphoma / Q000188:drug therapy* / Q000473:pathology; D045744:Cell Line, Tumor; D004357:Drug Synergism; D006801:Humans; D006918:Hydroxyurea / Q000008:administration & dosage / Q000494:pharmacology; D000069283:Rituximab; D014750:Vincristine / Q000008:administration & dosage / Q000494:pharmacology
chemical_list: D058846:Antibodies, Monoclonal, Murine-Derived; D000069283:Rituximab; D014750:Vincristine; D006918:Hydroxyurea