Name | Chlorotoxin |
Synonyms | CLTX Chlorotoxin CLTX (EGYPTIAN SCORPION) |
CAS | 163515-35-3 |
Molecular Formula | C158H256N52O48S11 |
Molar Mass | 3995.7 |
Solubility | aqueous buffer: soluble |
Appearance | Morphological lyophilized powder |
Storage Condition | 提取物 |
Physical and Chemical Properties | The bioactive Chlorotoxin is a 36-amino acid peptide extracted from the venom of the Israeli scorpion of the genus Thundersnake, which has anti-cancer activity. Chlorotoxin are chloride channel (chloride channel) blockers. |
Use | Application of new drugs for selective targeting of human glioma. |
WGK Germany | 3 |
1mg | 5mg | 10mg | |
---|---|---|---|
1 mM | 0.25 ml | 1.251 ml | 2.503 ml |
5 mM | 0.05 ml | 0.25 ml | 0.501 ml |
10 mM | 0.025 ml | 0.125 ml | 0.25 ml |
5 mM | 0.005 ml | 0.025 ml | 0.05 ml |
overview
Chlorotoxin (chlorotoxin) is a scorpion toxin polypeptide isolated from Israeli scorpion Leiurus quinquestraqtum. It has great application prospects as a new drug for selective targeting of human glioma and a specific marker for diagnosis (including grade judgment).
mechanism of action
Human astrocytoma produces a unique voltage-dependent chloride ion current (called GCC current, and its chloride ion channel is called GCC channel), which is used in human normal cells (including normal glial cells) and It is not produced in human tumor cells of non-glial origin. This chlorine current can be effectively inhibited by the Cl-channel inhibitor chlorotoxin and cause changes in the reproduction speed of brain tumor cells, it is speculated that Cl-channels are involved in the regulation of astrocytoma growth. Chlorotoxin-sensitive GCC currents persist in implanted glioma cells and do not occur in adjacent normal host glial cells. This unique chloride channel is confirmed to be unique to glioma. The selective combination of chlorotoxin to this chloride channel provides a new and effective way to identify and treat glioma. Chlorotoxin selectively binds to glioma cells, while normal human tissues including brain, kidney, intestine, etc. show negative immunostaining of chlorotoxin.
Main References
[1] Zeng Xianchun, Li Wenxin. Anti-glioma effect of chlorotoxin [J]. Chemistry of Life, 1999,(04):49-50.
Target
Target: Chloride Channel
in vitro studies
Chlorotoxin (Chlorotoxin) preferentially binds to tumor cells and has been harnessed to develop an imaging agent to help visualize tumors during surgical resection. In addition, chlorotoxin has potential as a vehicle to deliver anti-cancer drugs specifically to cancer cells. Chlorotoxin is shown to bind glioma cells, but is unable to bind normal rat astrocytes and Te671, a human rhabdomyosarcoma cell line. Chlorotoxin inhibits the migration of U251MG (glioma) cells, with an IC 50 of 600 nM. Chlorotoxin binds to glioma cells is specific and involves high affinity (K d =4.2 nM) and low affinity (K d =660 nM) binding sites.Small conductance chloride channels are shown to be potently blocked by Chlorotoxin. Chlorotoxin has been used as a general pharmacological tool to investigate the function of chloride channels.
In vivo studies
Chlorotoxin shows insecticidal activity on insects and other invertebrates. After the administration of I-Chlorotoxin to tumor-bearing mice, the peptides accumulated within the tumor.Chlorotoxin selectively accumulates in the brain of tumor-bearing mice with calculated brain: muscle ratios of 36.4% of injected dose/g (ID/g), as compared to 12.4%ID/g in control animals.