title: Therapeutic effects of γ-irradiation in a primary effusion lymphoma mouse model.
abstract: Primary effusion lymphoma (PEL) is a unique and recently identified non-Hodgkin's lymphoma in immunocompromised individuals. PEL is caused by the Kaposi sarcoma-associated herpes virus/human herpes virus 8 (KSHV/HHV-8) and has a peculiar presentation involving liquid growth in the serous body cavity, chemotherapy resistance and poor prognosis. In search of a new therapeutic modality for PEL, we examined the effect of γ-irradiation on PEL-derived cell lines (BCBL-1, BC-1, and BC-3) in vitro and in vivo. An MTT assay and trypan blue exclusion assay revealed that irradiation significantly suppressed cell proliferation in the PEL cell lines in a dose-dependent manner, and induced apoptosis. The PEL cell lines were relatively radiosensitive compared with other hematological tumor cell lines (Raji, Jurkat, and K562 cells). Inoculation of the BC-3 cell line into the peritoneal cavity of Rag2/Jak3 double-deficient mice led to massive ascites formation, and subcutaneous injection of BCBL-1 led to solid lymphoma formation. Total body irradiation (4 Gy × 2) with bone marrow transplantation resulted in the complete recovery of both types of PEL-inoculated mice. These results suggest that total body irradiation with bone marrow transplantation can be successfully applied for the treatment of chemotherapy-resistant PEL.
authors.affiliation: Division of Hematopoiesis, Center for AIDS Research; ; Radioisotope Center, Institute of Resource Development and Analysis, Kumamoto University, Kumamoto 860-0811,  Japan.
authors.forename: Yoshioki
authors.initials: Y
authors.lastname: Shiraishi
authors.forename: Kumiko
authors.initials: K
authors.lastname: Gotoh
authors.forename: Tomomi
authors.initials: T
authors.lastname: Towata
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Shimasaki
authors.forename: Shinya
authors.initials: S
authors.lastname: Suzu
authors.forename: Akihiro
authors.initials: A
authors.lastname: Kojima
authors.forename: Seiji
authors.initials: S
authors.lastname: Okada