| Objective:To investigate the clinical significance of macrophage inhibitory factor1(MIC1) in the diagnosis and prognosis of Esophageal Squamous Cell Carcinoma (ESCC), assess the treatment value of anti-MIC1antibody against the ESCC and explore its mechanisms, evalute the effection of MIC1antibody on self-renewal of ESCC cancer stem cell, and discuss the feasibility of combination of MIC1antibody with chemotherapy for ESCC, lay the foundation for MIC1in the diagnosis and treatment of ESCC.Methods:Serum samples were collected before any treatment for286patients with ESCC and250healthy subjects, one month post-surgery for110ESCC patients undergoing resection and post-surgery recurrence for20relapse patients; The performance of serum MIC1levels in the diagnosis of ESCC was evaluated and compared with SCC, CEA, CA199and CA724by ROC curve analysis; The correlation between serum levels of MIC1and clinical parameters, and the changement of MIC1level before and after treatment were analyzed, to evaluate the predictive and monitoring value of MIC1; The expression of MIC1in ESCC cell lines and tissue microarrays was qualitative analyzed, and the transcriptional level of MIC1in80pairs ESCC and matched normal tissues were detected by quantitative RT-PCR, and analyzed with clinical parameters, to evaluate the role of MIC1in ESCC; The inhibition of MIC1antibody on human ESCC cell was conducted on nude mouse model, and the distribution of the antibody was analyzed by in vivo fluorescence imaging system; The inhibition mechanism of MIC1antibody was investigated by H&E staining and immunohistochemical staining for tumor tissue sections; ALDH1+cancer stem cells was sorted through flow cytometry, the effection and mechanism of MIC1on self-renewal of stem cells was studied by flow cytometry and quantitative analysis of sternness genes; The inhibition of MIC1antibody against ESCC cancer stem cells in vitro and sensitizing effect of MIC1antibdoy combination with chemotherapy for ESCC were conducted by in vitro chemotherapy susceptibility assay.Results:The serum MICl of ESCC was significantly higher than normal groups (p<0.001), and was positively associated with the depth of tumor invasion (P=0.023) and lymph node metastasis (P=0.015). The sensitivity of MIC1was significantly better than SCC, CEA, CA199and CA724, especially for Phase Ⅰ ESCC. Patients with higher serum MIC1also had a poorer prognosis in relapse-free (P=0.050) and tumor-specific survival (P=0.005), monitoring of post-surgery serum MIC1is useful in evaluation of early recurrence. The expression of MIC1in ESCC cells was significantly elevated. The expression in tumor tissues was significantly higher than paired adjacent normal tissues (p=0.001), and associated with lymph node metastasis (p=0.025). The antibody of MIC1inhibited the tumor growth (p<0.001), and showing preference for MIC1over-expressing tumor tissues. H&E staining of Paraffin embedded tissue showed that lymphocytes were largely presented in tumor necrosis field, and CD31immunohistochemical staining showed that micro vessel density was significantly decreased (P<0.01), implied that the angiogenesis and immune system may be involved in the mechanism. The expression level of MIC1in tumor stem cells was significantly higher than non-stem cells and MIC1promoted the self-renewal of cancer stem cell. The Bmi-1may be involved in the mechanism. MIC1antibodies inhibit cancer stem cell self-renewal, MIC1antibody inhibited this function by neutralizing MIC1in medium, and the combined application increased the sensitivity of cancer stem cells to chemotherapeutic drugs.Conclusion:MIC1is a new serum marker for diagnosis and prognosis of ESCC, and also can be used to monitor patients during the treatment. MIC1antibody inhibits tumor angiogenesis and alters immunosuppressive status by adjusting tumor microenvironment. Additionally, MIC1can serve as a therapeutic target for ESCC cancer stem cells; MIC1antibody can increase the sensitivity of cancer stem cells to chemotherapeutic drugs by inhibiting self-renewal of cancer stem cells. |
PDF Full Text Request