Our virus-like particles (VLPs) have a unique tropism towards cancer cells based on their multivalent binding to modified tumor-associated glycosaminoglycans (GAGs) that are specifically found in solid tumors. We have consistently shown that our VLPs bind and kill multiple cancer cell lines in vitro with picomolar activity. In vivo, we have also observed selective binding and dose-dependent durable tumor regressions after a single systemic administration of bel-sar using xenografts of human tumor cell lines and allografts of murine tumor cell lines, like lung, ovarian, bladder, melanoma, prostate and colon. These results help to corroborate the thesis that many solid tumors appear to consistently express and specifically modify GAGs on the tumor cell membrane as part of the biology of tumor growth and early malignant transformation. Accordingly, we believe we may be able to treat a broad spectrum of solid tumors with our novel technology platform.