The Expression Of Indoleamine 2,3-dioxygenase In Breast Cancer And Its Correlation To Angiogenesis

Objective:To investigate the expression of Indoleamine 2,3-dioxygenase (IDO) in breast cancer and its correlation to clinicopathologic factors and prognosis. To investigate the expression of CD31,CD105 which can be used as markers of MVD. To investigate the relationship between IDO and MVD. Furthermore, using a co-culture system of MCF-7 and HUVEC, we will evaluate the effects of IDO on proliferation of HUVEC in vitro. We also detected the CD105 of HUVEC after the co-culturing. Moreover, IDO expression can promote the formation of vessel-like structures in vitro. These findings suggest that IDO may promote angiogenesis in vitro.Methods:1. The paraffin blocks of 40 cases of breast cancer were collected from Tianjin cancer hospital. Immunohistochemistry was used to detect the expression of IDO,CD31 and CD105 proteins in previous tissues, then to seek the relationship between them. We investigated the relationship between IDO and clinicopathologic factors and prognosis.2. RT-PCR was used to detect the mRNA of IDO in human breast cancer cell lines, such as MDA-MB-231,MDA-MB-435S,MDA-MB-453,SK-Br-3,MCF-7,T47D,ZR-75-1.3. Using a co-culture system of MCF-7 and HUVEC, we evaluate the effects of IDO on proliferation,the expression of CD105,the formation of vessel-like structures of HUVEC in vitro.Results:1. The overexpression ratio of IDO in breast cancer is 67.5%(27/40), and expression of IDO was closely associated with clinical stage and lymph nodes metastasis.2. The disease-free survival rate in patients with overexpression of IDO was lower than that in patients with negative or low expression of IDO (P>0.05)3. The expression of IDO was positively correlated with MVD-CD105 (P <0.05). 4. RT-PCR results showed that human breast cancer cell lines MCF-7,MDA-MB-435S,T47D are high expression of IDO. MDA-MB-231,MDA-MB-453,SK-Br-3,ZR-75-1 are low or no expression of IDO.5. Using a co-culture system of MCF-7 and HUVEC, IDO can promote the proliferation,the expression of CD105,the formation of vessel-like structures of HUVEC in vitro.Conclusion:1. The overexpression ratio of IDO in breast cancer is 67.5%.Expression of IDO was associated with clinical stage and lymph nodes metastasis.2. In breast cancer, the expression of IDO may be in relation to increase MVD, which suggested that IDO maybe induced tumor angiogenesis, then to promote cancer cells metastasis.Meanwhile, CD105 is a better marker than CD31 in cancer.3. Using a co-culture system of MCF-7 and HUVEC, we evaluate the effects of IDO on proliferation the expression of CD105,the formation of vessel-like structures of HUVEC in vitro.