Sandra M. Swain, MD and Sherry Yang, MD, PhD, Cancer Therapeutics Branch, NCI/CCR:

Evaluation of Angiogenesis Parameters and Tumor Markers in Inflammatory Breast Cancer (IBC) Specimens

A NIH IRB approved protocol titled “Evaluation of Angiogenesis Parameters and Tumor Markers in Inflammatory Breast Cancer (IBC) Specimens” to study 150 inflammatory breast cancer (IBC) cases from the IBC Biospecimen Repository at George Washington University and 150 non-IBC from the Co-operative Breast Cancer Tissue Resource is being carried out in the Molecular Profiling Core, CTB, CCR, NCI. This is a comprehensive translational research project directly relevant to identification and validation of biomarkers and/or therapeutic targets in IBC. Dr. Swain has a long-standing interest to study IBC both in translational research and patient treatment^1-3. The Molecular Profiling Core is an appropriate training ground for clinical and/or translational research fellows since Dr. Yang has extensive experience in analyzing patient tumor specimens and in translational research. The success is documented in many peer-reviewed publications^4-7.

AIMS/HYPOTHESIS OF THE PROPOSED RESEARCH:
Inflammatory breast cancer is an aggressive form of breast cancer with a rapid growth rate and high metastatic potential. The pathogenesis of this tumor is poorly understood. It is a highly angiogenenic and angioinvasive disease. Our group has published that the 15 year overall survival is 20% in IBC versus 50 % in stage IIIA breast cancer³. It is therefore imperative to identify molecular markers or therapeutic targets for IBC. Our hypothesis is that multiple factors may contribute to the inflammatory phenotype, highly angiogenic nature, and tumor aggressiveness of IBC. The hypothesis will be examined via several objectives. These are to investigate certain molecular markers and markers of angiogenesis in IBC to help distinguish it from non-inflammatory breast cancer, to study the underlying mechanism of high vascularization in IBC, and to associate these markers, individually or combined, with patient prognosis. Examination of ER, c-erb-2, E-cadherin, MVD, Ki67, podoplanin, VEGF-C, VEGF-A and phospho-KDR will accomplish these objectives that will help identify markers or therapeutic targets specific to IBC.

We have previously described that increased microvessel density (MVD) is associated with the inflammatory phenotype and a trend toward higher MVD in ER-negative tumor than in ER-positive tumor². VEGF-A is one of the most potent factors in angiogenesis playing a crucial role in both normal and pathologic angiogenesis. Higher levels of VEGF-A have been found in many tumor types including breast cancer⁸. VEGF-A binds to both VEGFR-1 and VEGFR-2 (also known as KDR); however, VEGFR-2 appears to be most important for its function. The activated form of this receptor is phospho-KDR and measuring its levels may be another useful approach to monitor VEGF activity and angiogenesis. VEGF expression has been shown to have significant correlation with MVD⁹ and also has been shown to be an independent predictor of tumor recurrence¹⁰, relapse-free and overall survival in node-negative and node-positive breast cancer patients. Associations between MVD and VEGF-A expression or phospho-KDR will be performed.

Metastasis to regional lymph nodes is often the first route of cancer progression. This is especially important in inflammatory breast cancer in which the majority of patients present with lymph node involvement. Recently, a number of molecular markers such as podoplanin and VEGF-C specific to lymphatic endothelium have been identified, which may help to understand the mechanisms of lymphagenesis and lymphatic invasion in IBC.

E-cadherin is a cell adhesion molecule that is expressed in normal breast tissue. E-cadherin is believed to act as a tumor suppressor that attenuates malignant behavior. Loss of E-cadherin expression has been found to correlate with poor prognosis¹¹. However, IBC has been associated with overexpression of E-cadherin. Further investigation has demonstrated IBC to be associated with intact and overexpressed E-cadherin and the lack of sialyl-Lewis (x/a) carbohydrate ligand-binding epitope. These biological characteristics may be one of the explanations for the histological appearance of lymphovascular emboli in IBC. This may be an explanation for the aggressive metastatic behavior of IBC since compact tumor emboli are very efficient at metastatic dissemination¹².

REFERENCES

1. Swain SM, Sorace RA, Bagley CS, et al: Neoadjuvant chemotherapy in the combined modality approach of locally advanced nonmetastatic breast cancer. Cancer Res 47:3889-94, 1987
2. McCarthy NJ, Yang X, Linnoila IR, et al: Microvessel density, expression of estrogen receptor alpha, MIB-1, p53, and c-erbB-2 in inflammatory breast cancer. Clin Cancer Res 8:3857-62, 2002
3. Low JA, Berman AW, Steinberg SM, et al: Long-term follow-up for locally advanced and inflammatory breast cancer patients treated with multimodality therapy. J Clin Oncol 22:4067-74, 2004
4. Yang SX, Simon RM, Tan AR, et al: Gene expression patterns and profile changes pre- and post-erlotinib treatment in patients with metastatic breast cancer. Clin Cancer Res 11:6226-32, 2005
5. Tan AR, Yang X, Hewitt SM, et al: Evaluation of biologic end points and pharmacokinetics in patients with metastatic breast cancer after treatment with erlotinib, an epidermal growth factor receptor tyrosine kinase inhibitor. J Clin Oncol 22:3080-90, 2004
6. Tan AR, Yang X, Berman A, et al: Phase I trial of the cyclin-dependent kinase inhibitor flavopiridol in combination with docetaxel in patients with metastatic breast cancer. Clin Cancer Res 10:5038-47, 2004
7. Yang X, Groshen S, Formenti SC, et al: P7 antigen expression in human breast cancer. Clin Cancer Res 9:201-6, 2003
8. Lee AH, Dublin EA, Bobrow LG, et al: Invasive lobular and invasive ductal carcinoma of the breast show distinct patterns of vascular endothelial growth factor expression and angiogenesis. J Pathol 185:394-401, 1998
9. Obermair A, Bancher-Todesca D, Bilgi S, et al: Correlation of vascular endothelial growth factor expression and microvessel density in cervical intraepithelial neoplasia. J Natl Cancer Inst 89:1212-7, 1997
10. Eppenberger U, Kueng W, Schlaeppi JM, et al: Markers of tumor angiogenesis and proteolysis independently define high- and low-risk subsets of node-negative breast cancer patients. J Clin Oncol 16:3129-36, 1998
11. Parker C, Rampaul RS, Pinder SE, et al: E-cadherin as a prognostic indicator in primary breast cancer. Br J Cancer 85:1958-63, 2001
12. Alpaugh ML, Tomlinson JS, Ye Y, et al: Relationship of sialyl-Lewis(x/a) underexpression and E-cadherin overexpression in the lymphovascular embolus of inflammatory breast carcinoma. Am J Pathol 161:619-28, 2002