The mature B cell lymphoma studied here is similar to the non-Hodgkin lymphoma studied by R. Mangues, et al., who demonstrated that L-744,832 could prevent the formation of diffuse large B cell splenic lymphomas in mice that expressed an activated N-Ras oncogene under the MMTV promoter [8]. This evidence concerns the gene NRAS and splenic diffuse large B-cell lymphoma.