Tumours and tissues were snap-frozen on dry ice and stored at 80 C or placed in 10% neutral buffered formalin (Fisher Scientific, 22-110-761) for 24 h and then stored in 100% methanol (Fisher Scientific, A412P-4)
This is where careful preformulation drug characterization is needed in order to fully understand and predict the nature of niclosamides solid forms, its resulting solubility in aqueous media, and hence its bioavailability, in (any) dosage form
Western blot analysis RIPA Lysis Buffer (TransGen, Beijing, China) was used to extract total protein from tissues/fibroblasts and a Nuclear and Cytoplasmic Protein Extraction Kit (TransGen) was used to extract the protein from nucleus and cytoplasm of fibroblasts
These ideas are in line with metalloproteomics experiments in Saccharomyces cerevisiae , which reveal that 20 cell-abundant Zn II metalloenzymes, if fully metalated, account for 90% of the zinc quota in the cell, one of which is methionine aminopeptidase