Indoleamine 2,3-dioxygenase is a novel prognostic indicator for endometrial cancer.
Indoleamine 2,3-dioxygenase (IDO) is a tryptophan-catabolising enzyme inducing immune tolerance. The present study aimed to investigate IDO expression and its prognostic significance in endometrial cancer. Indoleamine 2,3-dioxygenase expression in endometrial cancer tissues (n = 80) was immunohistochemically scored as four groups (IDO-, 1+, 2+, and 3+). The high IDO expression (IDO2+ or 3+) in tumour cells was found in 37 (46.3%) of the 80 cases, and was positively correlated with surgical stage, myometrial invasion, lymph-vascular space involvement, and lymph node metastasis, but not with the histological grade. Patients with high IDO expression had significantly impaired overall survival and progression-free survival (PFS) (P = 0.002 and P = 0.001, respectively) compared to patients with no or weak expression of IDO (IDO- or 1+). The 5-year PFS for IDO-/1+, 2+, and 3+ were 97.7, 72.9, and 36.4%, respectively. Even in patients with early-stage disease (International Federation of Gynecology and Obstetrics I/II, n = 64), the PFS for IDO2+/3+ was significantly poor (P = 0.001) compared to that for IDO-/1+. On multivariate analysis, IDO expression was an independent prognostic factor for PFS (P = 0.020). These results indicated that the high IDO expression was involved in the progression of endometrial cancer and correlated with the impaired clinical outcome, suggesting that IDO is a novel and reliable prognostic indicator for endometrial cancer.
Ino
K
K
Department of Obstetrics and Gynecology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan. kazuino@med.nagoya-u.ac.jp
Yoshida
N
N
Kajiyama
H
H
Shibata
K
K
Yamamoto
E
E
Kidokoro
K
K
Takahashi
N
N
Terauchi
M
M
Nawa
A
A
Nomura
S
S
Nagasaka
T
T
Takikawa
O
O
Kikkawa
F
F
D014408:Biomarkers, Tumor / Q000032:analysis*; D015153:Blotting, Western; D018269:Carcinoma, Endometrioid / Q000378:metabolism* / Q000401:mortality / Q000473:pathology*; D018572:Disease-Free Survival; D016889:Endometrial Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase / Q000096:biosynthesis*; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D016019:Survival Analysis
D014408:Biomarkers, Tumor; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase