Biomarker: IDO

Histology type: endometrial carcinoma

Country: Turkey

Region: Malatya

Study type: prospective cross-sectional study

Followed up time :

Subgroup 1 name : study

Subgroup 1 number: 38

Subgroup 2 name: control

Subgroup 2 number: 21

Conclusion: Serum IDO levels were significantly higher in women with endometrial cancer than in those without cancer. These results may help identify new markers for diagnosing endometrial cancer.

Sample type : serum

Sample method: immunoassay analysis

Expression pattern : high level

Expression elevation: cutoff=6.56 ng/mL

Statictics: Mean ;Range

Subgroup 1 age: 58.5;38–81

Subgroup 2 age: 46;38–73

Funtion Uniprot: Catalyzes the first and rate limiting step of the catabolism of the essential amino acid tryptophan along the kynurenine pathway (PubMed:17671174). Involved in the peripheral immune tolerance, contributing to maintain homeostasis by preventing autoimmunity or immunopathology that would result from uncontrolled and overreacting immune responses (PubMed:25691885). Tryptophan shortage inhibits T lymphocytes division and accumulation of tryptophan catabolites induces T-cell apoptosis and differentiation of regulatory T-cells (PubMed:25691885). Acts as a suppressor of anti-tumor immunity (PubMed:23103127, PubMed:25157255, PubMed:14502282, PubMed:25691885). Limits the growth of intracellular pathogens by depriving tryptophan (PubMed:25691885). Protects the fetus from maternal immune rejection (PubMed:25691885).

UniProt ID: P14902

UniProt Link: https://www.uniprot.org/uniprotkb/P14902/entry

Biological function from UniProt: Immunity, Tryptophan catabolism

Molecular function from UniProt:

Tissue specificity from UniProt: Expressed in mature dendritic cells located in lymphoid organs (including lymph nodes, spleen, tonsils, Peyers's patches, the gut lamina propria, and the thymic medulla), in some epithelial cells of the female genital tract, as well as in endothelial cells of term placenta and in lung parenchyma (PubMed:25691885). Weakly or not expressed in most normal tissues, but mostly inducible in most tissues (PubMed:25691885). Expressed in more than 50% of tumors, either by tumoral, stromal, or endothelial cells (expression in tumor is associated with a worse clinical outcome) (PubMed:18418598). Not overexpressed in tumor-draining lymph nodes (PubMed:26155395, PubMed:25691885)

Subcellular UniProt: #Cytoplasm

Alternative name from UniProt:

Miscellaneous: IDO1 is the target for therapy in a range of clinical settings, including cancer, chronic infections, autoimmune and allergic syndromes, and transplantation.1 Publication IDO1 and IDO2 are 2 distinct enzymes which catalyze the same reaction. IDO2 affinity for tryptophan is much lower than that of IDO1. 50% of Caucasians harbor polymorphisms which abolish IDO2 enzymatic activity. IDO2 is expressed in human tumors in an inactive form: tryptophan degradation is entirely provided by IDO1 in these cells (PubMed:18418598). IDO2 may play a role as a negative regulator of IDO1 by competing for heme-binding with IDO1 (PubMed:25394548). Low efficiency IDO2 enzymes have been conserved throughout vertebrate evolution, whereas higher efficiency IDO1 enzymes are dispensable in many lower vertebrate lineages (PubMed:25950090). IDO1 may have arisen by gene duplication of a more ancient proto-IDO gene before the divergence of marsupial and eutherian (placental) mammals3 Publications Elevated IDO1 expression is a hallmark of major viral infections including HIV, HBV, HCV or influenza and also of major bacteria infections, such as Tb, CAP, listeriosis and sepsis. Depletion of tryptophan and production of tryptophan metabolites with bactericidal activity are important as direct anti-pathogen mechanisms. Pathogens are able to highjack the immunosuppressive effects of IDO1 and make use of them to facilitate their own life cycle.

Gene name from HGNC: IDO1 (IDO, INDO)

HPA link: https://www.proteinatlas.org/ENSG00000131203-IDO1

Tissue specificity RNA from HPA: Tissue enhanced (lymphoid tissue, placenta)

Subcellular summary HPA Located in Nucleoplasm, Vesicles, Mitochondria, Cytosol (Single cell variability)

Cancer prognostic summary HPA Prognostic marker in renal cancer (unfavorable), ovarian cancer (favorable) and melanoma (favorable)

Pathology link: https://www.proteinatlas.org/ENSG00000131203-IDO1/pathology

Pathology endo: https://www.proteinatlas.org/ENSG00000131203-IDO1/pathology/endometrial+cancer

OMIM: 147435

OMIM link2: https://www.omim.org/entry/147435

HGNC ID: HGNC:6059;HGNC:27269;

HGNC link: https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:6059;https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:27269;