{Reference Type}: Journal Article {Title}: Review of 10 years of research on breast cancer patients: Focus on indoleamine 2,3-dioxygenase. {Author}: Asghar K;Farooq A;Zulfiqar B;Loya A; {Journal}: World J Clin Oncol {Volume}: 12 {Issue}: 6 {Year}: Jun 2021 24 暂无{DOI}: 10.5306/wjco.v12.i6.429 {Abstract}: Therapeutic manipulation of the immune system in cancer has been an extensive area of research in the field of oncoimmunology. Immunosuppression regulates antitumour immune responses. An immunosuppressive enzyme, indoleamine 2,3-dioxygenase (IDO) mediates tumour immune escape in various malignancies including breast cancer. IDO upregulation in breast cancer cells may lead to the recruitment of regulatory T (T-regs) cells into the tumour microenvironment, thus inhibiting local immune responses and promoting metastasis. Immunosuppression induced by myeloid derived suppressor cells activated in an IDO-dependent manner may enhance the possibility of immune evasion in breast cancer. IDO overexpression has independent prognostic significance in a subtype of breast cancer of emerging interest, basal-like breast carcinoma. IDO inhibitors as adjuvant therapeutic agents may have clinical implications in breast cancer. This review proposes future prospects of IDO not only as a therapeutic target but also as a valuable prognostic marker for breast cancer.