High expression of CXCR4 in HER2 negative breast cancer patient may contribute to lymph node metastasis

• Main Authors: Chin-Sheng Hung, 洪進昇
• Other Authors: 李伯皇
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/70078996122203709811

碩士 === 國立臺灣大學 === 臨床醫學研究所 === 96 === Purposes of the study: Lymph node metastasis is an important prognostic factor in breast cancer, and lymph node metastasis may be the initial step for further distal metastasis. Therefore, identifying the contributing factors of lymph node metastasis in breast cancer may be helpful to understand the mechanism of metastasis. CXC chemokine receptor 4（CXCR4）is a member of chemokine receptor which is mostly expressed in immune cells. However, many studies report the expression in cancer cell and the relationship between cancer metastasis and CXCR4 expression. So, our study is to identify the correlation between the CXCR4 expression and axillary lymph node metastasis. This study investigate the influence of hormone receptor and HER2/neu expression. Material and method: Patients who had distal metastasis, T4 or N3 stage breast cancer, predominant ductal carcinoma in situ, received neoadjuvant chemotherapy or no lymph node data available were excluded. Eighty breast cancer patients between January 2006 and December 2006 were enrolled. All patients received the breast surgery and axillary lymph node dissection or sentinel lymph node sampling. Breast cancer tissue fixed with formalin and embedded with paraffin was obtained and stained with anti-CXCR4 antibody (MAB170, R&D system). This immunohistochemistry (IHC) stain result was interpreted by expert pathologists and then analyzed by image analysis software (Image-pro plus Ver 5.1). According to image analysis result of IHC stain, we divide patients into two groups as CXCR4 high and low expression. The results with age, tumor size, lymph node metastasis, estrogen receptor (ER), progesterone receptor (PR), and HER2/neu were examined by chi-square or Fisher’s exact test. Result: There is no significant difference between CXCR4 expression and pathological characteristics. But, there is significant difference between CXCR4 expression and lymph node metastasis in HER2/neu negative (p = 0.04) and hormone receptor positive patients (p = 0.02 in ER and p = 0.03 in PR). Conclusion: Our finding is that CXCR4 high expression contributes to axillary lymph node metastasis, especially when HER2/neu is negative. In other words, CXCR4 may be an alternative pathway in tumor invasion and metastasis when HER2/neu is not working. Another result is that CXCR4 high expression in hormone receptor positive patient associate with axillary lymph node metastasis. However, the really relationship between hormone receptor and CXCR4 is not quite clear and it needs further study. But, if CXCR4 really has influence on hormone receptor positive cancer cell, maybe that’s the reason why we use hormone therapy could achieve better outcome.