Notably, higher levels of Sphingomonas in healthy mammary tissue compared to tumor tissue have been linked to increased expression of Toll-like receptors (TLR2, TLR5, and TLR9) and antimicrobial effectors such as IL-12A, bactericidal/permeability-increasing protein (BPI), and myeloperoxidase (MPO). This evidence concerns the gene MPO and neoplasm.