Abstract: Clean version of Abstract Small interfering RNA (siRNA) for inhibiting the expression of the mini-chromosome maintenance 7 (MCM7) gene, and a composition and use thereof are provided. The siRNA designed and verified by the present disclosure can effectively inhibit the expression of the MCM7 gene, and thus inhibit the DNA synthesis, cell proliferation, and colony formation of cancer cells, thereby achieving the purpose of preventing and treating a tumor. The present disclosure provides a new target and candidate compound for cancer prevention or treatment.

Abstract: The present invention provides the preparation processes for several crystal forms of the compound 17beta-Neriifolin (17bNF) and use thereof in anti-tumor applications. The present invention provides preparation processes for four kinds of non-solvated crystal forms, amorphous powders and eleven kinds of solvated crystalline solids, including ethanol-solvated ones, of 17bNF that are not present in nature, and the identification and characterization of these crystal forms by crystallographic research methods such as X-ray powder diffraction. In addition, through vivo anti-tumor experiments with five of the crystal forms in nude mice, we provide anti-tumor and anti-cancer applications of the crystal forms of 17bNF.