Ablation of Stromal Cells with a Targeted Proapoptotic Peptide Suppresses Cancer Chemotherapy Resistance and Metastasis

Adipose stromal cells (ASCs) recruited by tumors contribute to the population of cancer-associated fibroblasts. ASCs have been reported to induce tumor growth and chemotherapy resistance. The effect of ASCs on metastasis has not been explored. Here, we investigated the role of ASCs in cancer aggressiveness and tested them as a therapy target. We show that ASCs promote the epithelial-mesenchymal transition and invasiveness of triple-negative breast cancer cells. In human cell lines derived from various types of breast tumors, ASCs suppressed cytotoxicity of cisplatin and paclitaxel. D-CAN, a proapoptotic peptide targeting ASC, suppressed spontaneous breast cancer lung metastases in a mouse allograft model when combined with cisplatin. Moreover, in a human breast cancer xenograft model, treatment with D-CAN alone was sufficient to suppress lung metastases. This study improves our understanding of how tumor stromal cells recruited from fat tissue stimulate carcinoma progression to chemotherapy resistance/metastasis and outlines a new approach to combination cancer treatment.