NK/T non-Hodgkin’s lymphoma xenografts as a model for therapeutic intervention

B28 NK/T cell non-Hodgkin’s lymphomas (NHL) occur more frequently in Asia and areas of South and Central America but are rare in United States and other Western populations. Disseminated NK/T NHL are mostly incurable and respond poorly to conventional, anthracycline-base regimens. We have established an EBV positive NK lymphoma xenograft (NK-S1) in SCID mice from the testicular metastasis of a patient with nasal-type NK lymphoma. NK-S1 still retained the same immunophenotypic features as the original tumor, and it was shown to be positive for cytoplasmic CD3, TIA-1, granzyme B and EBER. Furthermore, we have used this xenograft as a model for drug testing and showed previously that doxorubicin had no effect on the growth of subcutaneous NK-S1 xenografts. In this study, we found that treatment with gemcitabine caused complete remission of NK-S1 tumors at 60mg/kg by intraperitoneal injection on either the q3d x2 or q7d x4 schedules. Regression of tumors was visible at 24 h after treatment. Although weight loss was observed in the gemcitabine treated mice, the regimens used did not lead to other severe side effects or death. In conclusion, NK-S1 xenograft model can serve as a useful tool to provide representative in vivo platform for rational preclinical drug testing.