BMP2 and monocytic leukemia: Olioso et al. described the effect of Arnica montana L on the gene expression of the human monocytic leukemia cell line THP-1, reporting that homeopathic preparations of Arnica upregulated the expression of genes, such as CCL7, CXCL1, CXCL2, interleukin 8, and bone morphogenetic protein 2 (BMP2) (1).