Abstract
INTRODUCTION: A number of evidences have proved that "Nostoc commune" Vauch can improve human immunity and prevent diseases, however, the specific mechanism remains unclear. The biological activity of the main protein component of "Nostoc commune" Vauch extracellular matrix- a water-stress protein (WSP) still needs to be elucidated. METHODS: In our study, we validated the role of WSP in gastric cancer metastasis at the cellular level, the organoid level and in mouse models, and also studied the role of EGFRVIII and downstream signaling molecules after WSP treatment. RESULTS: We found that WSP can significantly inhibit the metastasis of gastric cancer cells. Interestingly, we found that the anti-metastasis ability of WSP on gastric cancer was related to membrane protein receptor EGFRVIII, which was realized by inhibiting the downstream EGFRVIII signaling pathway. In terms of mechanism, WSP can inhibit the downstream EGFRVIII signaling pathway Akt-PI3K and further inhibit the secretion of cancer-related metastasis proteins such as MMP2 and MMP9, thus, significantly affecting the metastasis of gastric cancer cells. DISCUSSION: Given the anticancer properties of WSP, drug developers and manufacturers can further develop protein drugs for cancer patients using protein engineering techniques based on the properties of WSP.