TNF and monocytic leukemia: A recent study has shown that Lactobacillus reuteri enhanced tumor necrosis factor (TNF)-induced apoptosis in human chronic myeloid leukemia-derived cells (18) and that bacterial soluble factors secreted by Lactobacillus casei rhamnosus caused induction of apoptosis in human monocytic leukemia-cell line, THP-1 (19).