Abstract: Two new metal-based anticancer chemotherapeutic
agents, [(Ph2Sn)2(HGuO)2(phen)Cl2] 1 and [(Ph3Sn)(HGuO)(phen)]-
Cl.CH3OH.H2O 2, were designed, prepared and characterized by
analytical and spectral (IR, ESI-Mass, 1H, 13C and 119Sn NMR)
techniques. The proposed geometry of Sn(IV) in 1 and 2 is distorted
octahedral and distorted trigonal-bipyramidal, respectively. Both 1
and 2 exhibit potential cytotoxicity in vitro against MCF-7, HepG-2
and DU-145 cell lines. The intrinsic binding constant (Kb) values of 1
(2.33 × 105 M-1) and 2 (2.46 × 105 M-1) evaluated from UV-Visible
absorption studies suggest non-classical electrostatic mode of
interaction via phosphate backbone of DNA double helix. The Stern-
Volmer quenching constant (Ksv) of 1 (9.74 × 105 M-1) and 2 (2.9 ×
106 M-1) determined by fluorescence studies suggests the groove
binding and intercalation mode for 1 and 2, respectively. Effective
cleavage of pBR322 DNA is induced by 1.Their interaction with
DNA of cancer cells may account for potency.
Abstract: To determine if the murine insulinoma, β-TC-6, is a
suitable substitute for primary pancreatic β-cells in the study of β-
cell functional heterogeneity, we used three distinct functional assays
to ascertain the cell line-s response to glucose or a glucose analog.
These assays include: (i) a 2-NBDG uptake assay; (ii) a calcium
influx assay, and; (iii) a quinacrine secretion assay. We show that a
population of β-TC-6 cells endocytoses the glucose analog, 2-
NBDG, at different rates, has non-uniform intracellular calcium ion
concentrations and releases quinacrine at different rates when
challenged with glucose. We also measured the Km for β-TC-6
glucose uptake to be 46.9 mM and the Vm to be 8.36 x 10-5
mmole/million cells/min. These data suggest that β-TC-6 might be
used as an alternative to primary pancreatic β-cells for the study of
glucose-dependent β-cell functional heterogeneity.