Differential dose effects of recombinant IL-25 on the development of dextran sulfate sodium-induced colitis

Objective

We evaluated different dose effects of rIL-25 on acute ulcerative colitis.

Materials and methods

Mice were fed 2.5% dextran sulfate sodium (DSS) for 5 days while infused i.p. with repeated doses of rIL-25 (0.2, 0.4 and 0.8 μg) in PBS or PBS only after every 24 h at the same time as the start of the DSS exposure. Clinical, macroscopical and microscopical assessment of colitis severity with survival study was performed. Colonic IL-25 expression and production of IFN-γ, IL-10 and IL-4 was also analyzed.

Results

At a dose of 0.2 μg, colitis was aggravated with high mortality, better improvements were observed at a dose of 0.4 μg, and colitis-induced diarrhea was reversed at a dose of 0.8 μg. The expression of IL-25 was found to decrease in severe colitis. Moreover, IL-25 inhibited production of mucosal IFN-γ, induced increase in IL-10 but not IL-4.

Conclusion

Improvements in DSS-induced colitis in response to IL-25 suggest IL-25's protective role by mechanisms including inhibition of IFN-γ with enhancement of anti-inflammatory release.

Comparative proteomics analysis of human osteosarcomas and benign tumor of bone

We conducted comparative proteomic analysis of osteosarcoma, with hopes of identifying the specific protein markers of osteosarcoma and improve the understanding of tumorigenesis and progression of osteosarcoma. Proteins extracted from osteosarcoma tissue and benign bone tumors, including osteoblastoma, chondroblastoma, and giant cell tumor of bone, were examined using two-dimensional gel electrophoresis followed by mass spectrometry analysis and database searches. We also validated the expression levels of interesting proteins by Western blotting assay and immunohistochemical staining. Intensity alterations of 30 spots were detected in osteosarcoma, and 18 of these spots were finally identified, including 12 up-regulated proteins and 6 down-regulated ones. The up-regulated proteins include VIM, TUBA1C, ZNF133, EZR, ACTG1, TF, and so on. The six down-regulated proteins include ADCY1, ATP5B, TUBB, RCN3, ACTB, and YWHAZ. Subsequent immunohistochemical staining and Western blotting assay for TUBA1C and ZNF133 in osteosarcoma samples confirmed the observation obtained by proteomic analysis. Our results suggest that these identified proteins may be potential biomarkers for osteosarcoma tumorigenesis and therapeutics. Aberrant expression of cytoskeletal- and microtubule-associated proteins in osteosarcoma may provide an advantage for tumor invasion and metastasis by affecting the stability of microtubule, which consequently influences the prognosis of patients.

Early exposure of high-dose interleukin-4 to tumor stroma reverses myeloid cell-mediated T-cell suppression

Myeloid-derived suppressor cells (MDSCs) inhibit T-cell activity and promote tumor growth in tumor-bearing hosts. We sought to determine how to prevent the generation of these cells and modulate anti-tumor immunity at different times during tumor growth. Interleukin-4 (IL-4), a cytokine closely associated with the differentiation of myeloid cells, was expressed locally at the tumor site with its dose and expression time tightly regulated by a tet-off system. Early exposure of high-dose IL-4 to the tumor stromal cells effectively prevented the generation of myeloid suppressor cells and led to a T-cell-mediated tumor rejection. However, IL-4 had no effect a few days after tumor growth, when myeloid suppressor cells had been generated and T cells were tolerized. Importantly, coinoculation of IL-4 receptor (IL-4R)-deficient tumor cells with IL-4R competent, but not IL-4R-deficient myeloid cells led to IL-4-mediated tumor regression in IL-4R-deficient mice, indicating that IL-4 acts directly on myeloid cells. These results show a novel way to prevent T cells from MDSC-induced suppression, with important indications for cancer therapy.

Abstract 4653: Role of serum HE4 in studying ovarian cancer progression and response to therapy with ARCHITECT HE4 assay

Human epididymis protein 4 (HE4) is a whey acidic four-disulfide core protein. Serum HE4 has been shown to be a promising biomarker for epithelial ovarian cancer (EOC) with manual HE4 EIA assays. The ARCHITECT system is one of the major automated formats for cancer immunodiagnostics. This abstract describes the clinical performance of an investigational ARCHITECT HE4 assay in the measurement of serum HE4 from longitudinal samples of subjects with EOC and single-point samples from healthy subjects, and subjects with malignancy, benign diseases, EOC or other malignant diseases.

PROCEDURES: The ARCHITECT HE4 Assay is a paramagnetic microparticle chemiluminescent assay adopting the sensitive CHEMIFLEX® technology. Single-point and longitudinal serum samples were tested with an investigational ARCHITECT HE4 Assay reagent lot on the ARCHITECT i2000SR. Single-point sera were collected from healthy subjects (N = 400), subjects with pregnancy (N = 50) and benign disease (N = 612), and subjects which were diagnosed with EOC (N = 314) and other cancers (N = 250) including endometrial, breast, gastrointestinal, lung, and bladder cancer. Longitudinal sera (N = 506), including initial time point and follow-up visits (average = 5.7 per subject), were collected from subjects (N = 76) which were diagnosed with EOC. All of the single-point and longitudinal samples were handled in accordance with IRB-approved and GCP-compliant protocols.

RESULTS: Using an ARCHITECT HE4 cut-off value of >140 pmol/L, the percent distributions of ARCHITECT HE4 by cohort are: 3% of healthy subjects, 0% with pregnancy, 7.2% of subjects with benign diseases, 53.5% with EOC and 28.4% with other cancers. Using the upper 95% point of the distribution of the HE4 ratio at 14% to categorize the successive HE4 readings into those that were and were not significantly elevated for the longitudinal samples, the sensitivity, specificity and positive predictive value of HE4 elevation versus disease progression were 53.4% (95% CI: 44.1%-62.5%), 78.8% (95% CI: 74.7% - 82.4%) and 43.2% (95% CI: 32.9% - 54.1%) respectively. The total concordance between HE4 elevation and disease progression was 73%. Receiver Operator Characteristic analysis showed an area under the curve of 0.685 (SE = 0.033) for the diagnosis of progression from the ratio of successive HE4 readings. When comparing the change of the HE4 ratio with the diagnostic response to therapy, a decrease in HE4 reflected response to therapy with a sensitivity of 82% and a specificity of 53%.

CONCLUSIONS: The study with single-point samples has shown the utility of ARCHITECT HE4 values as a serum biomarker for EOC. The longitudinal increase of ARCHITECT HE4 values in sera seemed to be effective in recognizing the progression of EOC. The longitudinal decrease of ARCHITECT HE4 values in sera seemed to correlate with the response of EOC subjects to therapy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4653.