Indoleamine-2,3-dioxygenase 1/cyclooxygenase 2 expression prediction for adverse prognosis in colorectal cancer

AIM To evaluate indoleamine-2,3-dioxygenase 1/cyclooxygenase 2(IDO1/COX2) expression as an independent prognostic biomarker for colorectal cancer(CRC) patients.METHODS We retrospectively studied the medical records of 95 patients who received surgical resection from August 2008 to January 2010. All patients were randomly assigned to adjuvant treatment with or without celecoxib groups after surgery. We performed standard immunohistochemistry to assess the expression levels of IDO1/COX2 and evaluated the correlation of IDO1/COX2 with clinicopathological factors and overall survival(OS) outcomes.RESULTS The expression of nuclear IDO1 was significantly correlated with body mass index(P < 0.001), and IDO1 expression displayed no association with sex, age, tumor differentiation, T stage, N stage, carcinoembryonic antigen, cancer antigen 19-9, CD3+ and CD8+ tumor infiltrating lymphocytes, and COX2. In univariate analysis, we found that nuclear IDO1(P = 0.039), nuclear/cytoplasmic IDO1 [hazard ratio(HR) = 2.044, 95% confidence interval(CI): 0.871-4.798, P = 0.039], nuclear IDO1/COX2(HR = 3.048, 95%CI: 0.868-10.7, P = 0.0049) and cytoplasmic IDO1/COX2(HR = 2.109, 95%CI: 0.976-4.558, P = 0.022) all yielded significantly poor OS outcomes. Nuclear IDO1(P = 0.041), nuclear/cytoplasmic IDO1(HR = 3.023, 95%CI: 0.585-15.61, P = 0.041) and cytoplasmic IDO1/COX2(HR = 2.740, 95%CI: 0.764-9.831, P = 0.038) have significantly poor OS outcomes for the CRC celecoxib subgroup. In our multivariate Cox model, high coexpression of cytoplasmic IDO1/COX2 was found to be an independent predictor of poor outcome in CRC(HR = 2.218, 95%CI: 1.011-4.48, P = 0.047) and celecoxib subgroup patients(HR = 3.210, 95%CI: 1.074-9.590, P = 0.037).CONCLUSION Our results showed that cytoplasmic IDO1/COX2 coexpression could be used as an independent poor predictor for OS in CRC.

Feiji Recipe inhibits the growth of lung cancer by modulating T-cell immunity through indoleamine-2,3-dioxygenase pathway in an orthotopic implantation model

Objective： Escape from the body＇s immune response is a basic characteristic of lung cancer, and indoleamine-2,3-dioxygenase （IDO） plays a key role in mediating immune escape of non-small-cell lung cancer, which leads to recurrence and metastasis. Feiji Recipe, a compound Chinese herbal medicine, has the effect of stabilizing lesions and prolonging survival in patients with lung cancer. The purpose of this study was to investigate the mechanisms underlying the anticancer properties of Feiji Recipe. Methods： An orthotopic transplant model of mouse Lewis lung cancer, with stable expression of IDO gene, was established in C57BL/6 mice. Optical imaging was used to observe the effects of Feiji Recipe in the treatment of lung cancer in vivo. The effects of Feiji Recipe on the proliferation of mouse Lewis lung cancer cell line 2LL, 2LL-enhanced green fluorescent protein （2LL-EGFP） and 2LL-EGFP-IDO were investi- gated, and the apoptosis of T-cells was examined by 3-（4,5-dimethyl-2-thiazolyl）-2,5-diphenyl-2H-tetra zolium bromide using flow cytometry. Chemical composition of Feiji Recipe was validated by high- performance liquid chromatography. Results： Compared to the control group, the survival of animals treated with Feiji Recipe was significantly prolonged （P〈0.0074）, and the IDO protein level decreased （P=0.0072）; moreover, the percentages of CD4＋CD25＋ T-cells and Foxp3＋ T-cells were significantly decreased （P〈0.05）. The molecular mechanism of Feiji Recipe against lung cancer may relate to the regulation of immune cells, such as T-cells and reg- ulatory T-cells. Conclusion： The molecular mechanism of Feiji Recipe in treatment of lung cancer is to restore the function of T-cells in the cancer microenvironment through interfering with the IDO pathway.

Tryptophan 2,3-dioxygenase 2 controls M2 macrophages polarization to promote esophageal squamous cell carcinoma progression via AKT/GSK3β/IL-8 signaling pathway

Tryptophan 2,3-dioxygnease 2(TDO2) is specific for metabolizing tryptophan to kynurenine(KYN),which plays a critical role in mediating immune escape of cancer.Although accumulating evidence demonstrates that TDO2 overexpression is implicated in the development and progression of multiple cancers,its tumor-promoting role in esophageal squamous cell carcinoma(ESCC) remains unclear.Here,we observed that TDO2 was overexpressed in ESCC tis sues and correlated significantly with lymph node metastasis,advanced clinical stage,and unfavorable prognosis.Functional experiments showed that TDO2 promoted tumor cell proliferation,migration,and colony formation,which could be prevented by inhibition of TDO2 and aryl hydrocarb on receptor(AHR).Further experimentation demonstrated that TDO2 could promote the tumor growth of KYSE150 tumor-bearing model,tumor burden of C57 BL/6 mice with ESCC induced by 4-NQO,enhance the expression of phosphorylated AKT,with subsequent pho sphorylation of GSK3β,and polarization of M2 macrophages by upregulating interleukin-8(IL-8) to accelerate tumor progression in the tumor microenvironment(TME).Collectively,our results discovered that TDO2 could upregulate IL-8 through AKT/GSK3β to direct the polarization of M2 macrophages in ESCC,and suggested that TDO2 could represent as an attractive therapeutic target and prognostic marker to ESCC.

Recombinant adenovirus with human indoleamine-2,3- dioxygenase and hepatitis B virus preS was constructed and expressed in HepG2 cells

Background Indoleamine-2,3-dioxygenase （IDO） is proven to suppress hepatitis B virus （HBV） specific immune response and depletion of IDO may be a useful approach for HBV therapy. To test this concept, we constructed recombinant adenovirus with human IDO and HBV preS, which would form the basis for future in vivo experiments.Methods The fragment of human IDO and HBV preS cDNA were subcloned into multiple cloning sites in an adenoviral vector system containing two cytomegalovirus （CMV） promoters. Recombination was conducted in the Escherichia coli BJ5183. The recombinant adenovirus containing hlDO gene and HBVpreS gene was packaged and amplified in 293 cells.Integration was confirmed by polymerase chain reaction as well as the quantification of viral titers. HepG2 cells were infected with the recombinant adenovirus and mRNA and protein specific for hlDO and HBVpreS was detected by RT-PCR and Western blotting respectively.Results The recombinant adenovirus was produced successfully. Its titer was 2.5x109 efu/ml. IDO and HBVpreS mRNA as well as the encoded proteins could be found in transfected HepG2 cells, but not in control HepG2 cells.Conclusion The transfer of hlDO-HBVpreS with double-promoter adenoviral vector was efficient. The recombinant adenovirus with hlDO and HBVpreS would provide the experimental basis for future studies.