Three New Steroid Biglycosides, Plancisides A, B, and C, from the Starfish Acanthaster planci

Three new steroid biglycosides, plancisides A-C (1-3), were isolated from the ethanolic extract of the starfish Acanthaster planci. The structures of 1-3 were determined by extensive NMR and ESI-MS techniques, as (24 S)-28- O-[β-D-galactofuranosyl-(1→5)-α-L-arabinofuranosyl]-24-methyl-5α-cholestane-3β,4β,6α,8,15β,16β,28-heptol (1), (24 S)-28- O-[α-L-fucopyranosyl-(1→2)-3- O-methyl-β-D-xylopyranosyl]–24-methyl-5α-cholestane-3β,4β,6α,8,15β,16β,28-heptol (2) and (24 S)-28- O-[2,4-di- O-methyl-β-D-xylopyranosyl-(1→2)-α-L-arabinofuranosyl]-24-methyl-5α-cholestane-3β,4β,6α,8,15β,16β,28-heptol 6- O-sulfate (3), respectively. Compound 2 is the first steroid glycoside containing an α-fucopyranose unit found from starfish. Compound 1 slightly inhibits cell proliferation of HCT-116, T-47D, and RPMI-7951 cancer cell lines, but has no effect on colony formation of these cells in a soft agar clonogenic assay.

Two New Asterosaponins from the Far Eastern Starfish Lethasterias fusca

Two new asterosaponins, lethasteriosides A (1) and B (2), were isolated along with previously known thornasteroside A (3), anasteroside A (4), and luidiaquinoside (5) from the ethanolic extract of the Far Eastern starfish Lethasterias fusca. The structures of the new compounds were elucidated by extensive NMR and ESIMS techniques, and chemical transformations. Compounds 1 and 3–5 did not show any apparent cytotoxicity against cancer cell lines T-47D, RPMI-7951, and HCT-116, but glycoside 1, at concentration of 20 μM, demonstrated considerable inhibition of the T-47D (97%), RPMI-7951 (90%) and HCT-116 (90%) cell colony formations in a soft agar clonogenic assay.

Detection of neuroblastoma cells in bone marrow using GD2 specific monoclonal antibodies.

Three murine monoclonal antibodies (Mab) against a cell surface antigen, the disialoganglioside GD2, were investigated for detecting bone marrow metastasis in patients with neuroblastoma (NB) by indirect immunofluorescence (IF). As few as 0.01% NB cells could be detected. No Mab reactivity was found in 60 non-NB marrows. Thirty-five marrows from patients with stage III and stage IV NB at diagnosis were examined during the course of their disease. Tumor involvement was found in 74% by Mab, 55% by the two-layer soft agar clonogenic assay (CA), and 27% by conventional histochemical stains. All marrows containing NB histologically were positive for tumor by Mab; 71% were also positive by CA. Of histologically negative marrows, 63% were Mab positive, the majority (78%) of which were also positive by CA. All Mab nonreactive samples were negative histologically and by CA. We conclude that these antibodies are highly sensitive and specific in detecting NB metastasis in bone marrow.