Trace Metal Distribution and Correlation to Breast Cancer Progression and Metastasis Based on Synchrotron Radiation X-ray Fluorescence Imaging

Many trace metals are known to have important roles in the state of health and disease of individuals. Breast cancer, with highly invasive character, has been suggested to increased iron accumulation in the tumor. To investigate the role of iron in breast cancer progression and metastasis, 4T1 mammary carcinoma bearing mice was used to establish the human metastatic breast cancer model. Based on the methods of synchrotron radiation X-ray flourescence imaging (SXRF) with multi-elemental high sensitively and high spatial resolution, the distribution of iron, copper and zinc of 4T1 tumor at different growth stages on the 10th, 14th and 21st day after tumor inoculation was detected. Correspondingly, LCN2 and MMPs expressions in the corresponding tumor tissues were detected using immunohistochemistry analysis. The results showed that there was a significantly increased iron distribution during the tumor growth by SRXF. Accordingly, MMP2, MMP9 and LCN2 expression also increased significantly with the tumor growth. Our results suggested there might exist positive correlations of iron accumulation, LCN2 and MMP9 expression in tumor tissues during 4T1 tumor progression to metastasis.