Laetiporus sulphureus lectin inhibits angiogenesis and tumor development in the zebrafish xenograft models of colorectal carcinoma and melanoma.

Abstract

Laetiporus sulphureus, an edible mushroom, for centuries has been used in traditional European and Asian ethno-medicine. Its therapeutic properties have been attributed to different types of biologically active compounds, such as terpenes, polysaccharides, steroids, proteins and lectins. Recently, mushroom lectins emerged as very potent macromolecules with antiproliferative, cytotoxic, antiviral and immunostimulatory activities. Therefore, we isolated lectin from L. sulphureus (LSL) and evaluated its anti-angiogenic and anticancer activity in vivo, using the zebrafish model. We found that LSL is not toxic at high doses up to 400- 500 μg/mL, while it effectively inhibited angiogenesis and cancer development at much lower doses. Compared to sunitinib-malate, cardiotoxic and myelosupressive anti-angiogenic drug of clinical relevance, therapeutic potential of LSL was 378-fold higher. Wound healing and MTT assays were employed to examine antimigratory effect and endothelial cytotoxicity. Surprisingly, LSL affected human colorectal carcinoma and mouse melanoma cell lines, by almost completely diminishing their growth, neovascularization and metastasis. Moreover, in comparison to the used control (cisplatin), LSL showed markedly greater activity, while its potency turned out to be 8-fold higher towards colorectal carcinoma than melanoma. These encouraging data strongly imply that LSL can be considered for the application as supporting agent in chemotherapy against colorectal carcinoma and melanoma or used in pharmaceutical industry.