Synthesis of Biotinylated Glyfoline for Immunoelectron Microscopic Localization

Abstract

Antineoplastic glyfoline (1) has potent antitumor efficacy against various murine and human solid tumors. To elucidate the actual mechanism of action, we synthesized biotinylated glyfoline (B-Gly) and used it for the visualization of glyfoline-binding sites in nasopharyngeal carcinoma (NPC) cells. Under the electron microscope (EM), after cells were incubated for 6-36 h, the reaction products of anti-B-Gly were seen on some areas of the external cell surface and on the outer and inner membranes of the mitochondria. Pure EM morphology of NPC cells after glyfoline treatment revealed the similar morphological change of mitochondria. These findings indicate that the binding site of glyfoline in NPC is the inner membrane of the mitochondria, suggesting that B-Gly can be used as a marker for glyfoline localization.

Skeletal health among African Americans with recent‐onset rheumatoid arthritis

“…1 a ), an anti‐neoplastic 9‐acridone alkaloid first isolated from Glycosmis citrifolia , has been synthesized10 and shows potent antitumor activity against several murine and human tumors both in vitro and in vivo and is cytotoxic for doxorubicin‐resistant human leukemia HL‐60 cells 10, 11. Immunoelectron microscopic analysis of biotinylated glyfoline in nasopharyngeal carcinoma cells revealed that it accumulates at the inner mitochondrial membrane 12. Nasopharyngeal carcinoma cells treated with glyfoline were arrested at G2/M phase of the cell cycle and underwent apoptotic changes,13 indicating that glyfoline‐induced damage alters G2/M progression and results in apoptosis.…”

The correlation of serum protein association and cellular uptake with lipophilicity and polarity of the backbone substituents of the technetium‐99m‐amine‐oxime chelates

“…In our previous work of developing 99m Tc labeled amine-oxime containing 2-NI for tumor hypoxia targeting, 22 it had been noted that the accumulation level (a combination of selective-and non-selective-uptakes) in hypoxic Chinese hamster ovary (CHO) cells of the radiochelates had shown a correlation to their lipophilicity. It has been well known that lipophilicity is an key parameter that plays significant role in extracellular protein binding and in cellular uptake of a drug.…”

“…It has been well known that lipophilicity is an key parameter that plays significant role in extracellular protein binding and in cellular uptake of a drug. [16][17][18][19][20] However, according to our observation in the experiment, 22 polarity of a substituent on the backbone of a molecule may also play a significant role as does the lipophilicity in protein and cellular binding. In order to investigate the roles of these two structural parameters, this work uses two series of amine-oxime chelates, which at one end of the backbone has an attachment of alkyl chains with different lengths and at the other end either a 2-NI or an aniline group (Figure 1).…”

“…Our previous work has reported the development of amine-oxime chelating agents bearing a polar 2-nitroimidazole (2-NI) group to chelate 99m Tc for tumor hypoxia imaging. 22 Since an amine-oxime chelator contains a vicinal dioxime group, it may be able to chelate copper ions to form a stable chelates as well. 23 If it is the case, this series of chelators can be used to chelate 64 Cu and 67 Cu to produce agents for either tumor hypoxia PET imaging or tumor radiotherapy.…”

Cytochrome C Release Induces Apoptosis of Nasopharyngeal Carcinoma (NPC) by Antitumor Glyfoline

“…Additionally, we have synthesized biotinylated glyfoline (B-Gly) to elucidate other plausible mechanisms of action of the natural product. Immunoelectron microscopic localization assays of B-Gly demonstrated that the mitochondria of NPC were the primary target of glyfoline [8]. In this paper we describe additional studies on the mechanism of action of glyfoline.…”