SLC26A3 and breast cancer: Of note, SM-164 plus TNF Ab or CLD slightly but significantly increased tumor BLI levels in bone compared to SM-164 alone or SM-164 plus TNF (Fig. 1C), suggesting that blocking TNF signaling or depletion of macrophages attenuated the effect of SM-164 in inhibiting the growth of breast cancer in bone although SM-164 alone did not significantly reduce the growth of this advanced stage breast cancer.