4-acetamido-4--isothiocyanatostilbene-2-2--disulfonic-acid and Neoplasms

The hepatocyte growth factor receptor (HGFR or c-Met) is a driver of multiple cancer subtypes. While there are several c-Met inhibitors in development, few have been approved for clinical use, warranting the need for continued research and development of c-Met targeting therapeutic modalities. The research presented here demonstrates a particular class of compounds known as isothiocyanatostilbenes can act as c-Met inhibitors in multiple cancer cell lines. Specifically, we found that 4,4'-Diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS) and 4,4'-Diisothiocyanatodihydrostilbene-2,2'-disulfonic acid (H2DIDS) had c-Met inhibitory effective doses in the low micromolar range while 4-acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic acid (SITS) and 4,4'-dinitrostilbene-2, 2'-disulfonic acid (DNDS) exhibited IC50s 100 to 1000 fold higher. These compounds displayed much greater selectivity for inhibiting c-Met activation compared to similar receptor tyrosine kinases. In addition, DIDS and H2DIDS reduced hepatocyte growth factor (HGF)-induced, but not epidermal growth factor (EGF)-induced, cell scattering, wound healing, and 3-dimensional (3D) proliferation of tumor cell spheroids. In-cell and cell-free assays suggested that DIDS and H2DIDS can inhibit and reverse c-Met phosphorylation, similar to SU11274. Additional data demonstrated that DIDS is tolerable in vivo. These data provide preliminary support for future studies examining DIDS, H2DIDS, and derivatives as potential c-Met therapeutics.

Topics: 4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid; 4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid; Animals; Blotting, Western; Cell Line, Tumor; Cell Movement; Cell Proliferation; Dose-Response Relationship, Drug; Female; Hepatocyte Growth Factor; Humans; Mice, Nude; Neoplasms; Phosphorylation; Proto-Oncogene Proteins c-met; Stilbenes; Time Factors; Xenograft Model Antitumor Assays

A monoclonal antibody was prepared against DIDS, an inhibitor of anion transport, and used to compare the occurrence and distribution of DIDS-binding sites of tumorigenic and non-tumorigenic human somatic-cell hybrids. The monoclonal antibody (E8) was produced by the fusion of the mouse myeloma (NS-1) with mouse spleen cells and is of the IgG1 subclass. The apparent half-saturation of DIDS for HEp-2 cells is 16 microM and the reaction is rapid. The number of binding sites on tumorigenic and non-tumorigenic hybrid cells was the same. The DIDS-binding protein occurs homogeneously on all cells, a characteristic which distinguishes it from the possible tumour antigen recognised by the M/27 monoclonal antibody.

Topics: 4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid; 4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid; Antibodies, Monoclonal; Antibody Specificity; Binding Sites; Carrier Proteins; Cell Line; Cell Membrane; Cells, Cultured; HeLa Cells; Humans; Kinetics; Neoplasms; Stilbenes