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Journal of Nanobiotechnology Feb 2019Malignant glioma is the most common and deadliest brain cancer due to the obstacle from indistinct tumor margins for surgical excision and blood brain barrier (BBB) for...
BACKGROUND
Malignant glioma is the most common and deadliest brain cancer due to the obstacle from indistinct tumor margins for surgical excision and blood brain barrier (BBB) for chemotherapy. Here, we designed and prepared multifunctional polyethylenimine-entrapped gold nanoparticles (Au PENPs) for targeted SPECT/CT imaging and radionuclide therapy of glioma.
RESULTS
Polyethylenimine was selected as a template for sequential modification with polyethylene glycol (PEG), glioma-specific peptide (chlorotoxin, CTX) and 3-(4-hydroxyphenyl)propionic acid-OSu (HPAO), and were then used to entrap gold nanoparticles (Au NPs). After I radiolabeling via HPAO, the I-labeded CTX-functionalized Au PENPs as a multifunctional glioma-targeting nanoprobe were generated. Before I radiolabeling, the CTX-functionalized Au PENPs exhibited a uniform size distribution, favorable X-ray attenuation property, desired water solubility, and cytocompatibility in the given Au concentration range. The I-labeled CTX-functionalized Au PENPs showed high radiochemical purity and stability, and could be used as a nanoprobe for the targeted SPECT/CT imaging and radionuclide therapy of glioma cells in vitro and in vivo in a subcutaneous tumor model. Owing to the unique biological properties of CTX, the developed nanoprobe was able to cross the BBB and specifically target glioma cells in a rat intracranial glioma model.
CONCLUSIONS
Our results indicated that the formed nanosystem had the significant potential to be applied for glioma targeted diagnosis and therapy.
Topics: Animals; Cell Line, Tumor; Cell Survival; Disease Models, Animal; Drug Delivery Systems; Glioma; Gold; Humans; Male; Metal Nanoparticles; Mice; Peptides; Polyethyleneimine; Rats; Rats, Sprague-Dawley; Scorpion Venoms; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed
PubMed: 30782154
DOI: 10.1186/s12951-019-0462-6 -
ChemMedChem Nov 2020Malignant gliomas are the most lethal form of primary brain tumors. Despite advances in cancer therapy, the prognosis of glioma patients has remained poor. Cytochrome c...
Malignant gliomas are the most lethal form of primary brain tumors. Despite advances in cancer therapy, the prognosis of glioma patients has remained poor. Cytochrome c (Cytc), an endogenous heme-based protein, holds tremendous potential to treat gliomas because of its innate capacity to trigger apoptosis. To this end, a hybrid cytochrome c-chlorotoxin (Cytc-CTX) protein was biosynthesized to enable cellular uptake of the cell impenetrable Cytc using CTX transporters. A nucleotide sequence containing 1 : 1 Cytc and CTX was constructed and separated by a hexahistidine-tag and an enterokinase cleavage site. The sequence was cloned into a pBTR1 plasmid, expressed in Escherichia coli, purified via 2-dimensional chromatography. The identity and size of the protein were determined by Western blot and mass spectrometry. Cytc in this soluble hybrid protein has similar structure and stability as human Cytc and the hybrid protein is endocytosed into a glioma cell line, while displaying potent cytotoxicity and a favorable therapeutic index. Its facile, low-cost, and high yield synthesis, biocompatibility, and robustness suggest that the hybrid protein is a promising candidate for antiglioma drug evaluation.
Topics: Antineoplastic Agents; Brain Neoplasms; Cell Survival; Cells, Cultured; Cytochromes c; Dose-Response Relationship, Drug; Glioma; Humans; Scorpion Venoms; Structure-Activity Relationship
PubMed: 32918396
DOI: 10.1002/cmdc.202000373 -
World Journal of Biological Chemistry Feb 2017Animal venom research is a specialized investigation field, in which a number of different methods are used and this array is constantly expanding. Thus, recently...
Animal venom research is a specialized investigation field, in which a number of different methods are used and this array is constantly expanding. Thus, recently emerged omics and nanotechnologies have already been successfully applied to venom research. Animal venoms have been studied for quite a long time. The traditional reductionist approach has been to isolate individual toxins and then study their structure and function. Unfortunately, the characterization of the venom as a whole system and its multiple effects on an entire organism were not possible until recent times. The development of new methods in mass spectrometry and sequencing have allowed such characterizations of venom, encompassing the identification of new toxins present in venoms at extremely low concentrations to changes in metabolism of prey organisms after envenomation. In particular, this type of comprehensive research has become possible due to the development of the various omics technologies: Proteomics, peptidomics, transcriptomics, genomics and metabolomics. As in other research fields, these omics technologies ushered in a revolution for venom studies, which is now entering the era of big data. Nanotechnology is a very new branch of technology and developing at an extremely rapid pace. It has found application in many spheres and has not bypassed the venom studies. Nanomaterials are quite promising in medicine, and most studies combining venoms and nanomaterials are dedicated to medical applications. Conjugates of nanoparticles with venom components have been proposed for use as drugs or diagnostics. For example, nanoparticles conjugated with chlorotoxin - a toxin in scorpion venom, which has been shown to bind specifically to glioma cells - are considered as potential glioma-targeted drugs, and conjugates of neurotoxins with fluorescent semiconductor nanoparticles or quantum dots may be used to detect endogenous targets expressed in live cells. The data on application of omics and nanotechnologies in venom research are systematized concisely in this paper.
PubMed: 28289514
DOI: 10.4331/wjbc.v8.i1.4 -
British Journal of Pharmacology Feb 2000It was the aim of this study to look for a high-affinity and selective polypeptide toxin, which could serve as a probe for the volume-regulated anion channel (VRAC) or...
It was the aim of this study to look for a high-affinity and selective polypeptide toxin, which could serve as a probe for the volume-regulated anion channel (VRAC) or the calcium-activated chloride channel (CaCC). We have partially purified chlorotoxin, including new and homologous short chain insectotoxins, from the crude venom of Leiurus quinquestriatus quinquestriatus (Lqq) by means of gel filtration chromatography. Material eluting between 280 and 420 min, corresponding to fractions 15-21, was lyophilized and tested on VRAC and CaCC, using the whole-cell patch-clamp technique. We have also tested the commercially available chlorotoxin on VRAC, CaCC, the cystic fibrosis transmembrane conductance regulator (CFTR) and on the glioma specific chloride channel (GCC). VRAC and the correspondent current, I(Cl,swell), was activated in Cultured Pulmonary Artery Endothelial (CPAE) cells by a 25% hypotonic solution. Neither of the fractions 16-21 significantly inhibited I(Cl,swell) (n=4-5). Ca(2+)-activated Cl(-) currents, I(Cl,Ca), activated by loading T84 cells via the patch pipette with 1 microM free Ca(2+), were not inhibited by any of the tested fractions (15-21), (n=2-5). Chlorotoxin (625 nM) did neither effect I(Cl,swell) nor I(Cl,Ca) (n=4-5). The CFTR channel, transiently transfected in COS cells and activated by a cocktail containing IBMX and forskolin, was not affected by 1.2 microM chlorotoxin (n=5). In addition, it did not affect currents through GCC. We conclude that submicromolar concentrations of chlorotoxin do not block volume-regulated, Ca(2+)-activated and CFTR chloride channels and that it can not be classified as a general chloride channel toxin.
Topics: Animals; Astrocytoma; COS Cells; Calcium; Cells, Cultured; Chloride Channels; Cyclic AMP; Cystic Fibrosis Transmembrane Conductance Regulator; Endothelium, Vascular; Humans; Membrane Potentials; Pulmonary Artery; Scorpion Venoms; Substrate Specificity; Transfection
PubMed: 10683204
DOI: 10.1038/sj.bjp.0703102 -
Chinese Journal of Cancer Jun 2010Precisely locating tumors always proves to be difficult. To find a molecule that can specifically bind to tumor cells is the key. Recently, chlorotoxin (CTX) has been... (Review)
Review
Precisely locating tumors always proves to be difficult. To find a molecule that can specifically bind to tumor cells is the key. Recently, chlorotoxin (CTX) has been proved to be able to bind to many kinds of tumor cells. The CTX receptor on the cell surface has been demonstrated to be matrix metalloproteinase-2 (MMP-2). Many researchers have combined CTX with other molecules, including 131I, Cy5.5, iron oxide nanoparticles coated by polyethylene glycol (NP-PEG), and so on, and thus synthesized various types of probes that can be detected by gamma-camera, single photon emission computed tomography (SPECT) or magnetic resonance imaging (MRI). With these methods, the binding degree of CTX could be assessed. These studies demonstrated that CTX has a highly specific binding ability, high stability, and security. CTX could also inhibit or kill the tumor cells. A nonviral nanovector has been developed for gene therapy. As a result, it gradually develops into a new method of diagnosis and targeted therapy of tumors. This article reviews the current progress on CTX including the origin, chemical construction, the mechanism of binding with tumor cells, and the application to tumor imaging diagnosis and therapy.
Topics: Brain Neoplasms; Carbocyanines; Chloride Channels; Diagnostic Imaging; Ferric Compounds; Genetic Therapy; Glioma; Humans; Iodine Radioisotopes; Magnetic Resonance Imaging; Matrix Metalloproteinase 2; Nanoparticles; Neoplasm Invasiveness; Neoplasm Metastasis; Polyethylene Glycols; Scorpion Venoms; Tomography, Emission-Computed, Single-Photon
PubMed: 20507737
DOI: 10.5732/cjc.009.10359 -
Biomedicines Oct 2022Natural peptides isolated from animal venoms generally target cell surface receptors with high affinity and selectivity. On many occasions, some of these receptors are...
Natural peptides isolated from animal venoms generally target cell surface receptors with high affinity and selectivity. On many occasions, some of these receptors are over-expressed in cancer cells. Herein, we identified Lqh-8/6 as a natural peptide analog of chlorotoxin, a proven and useful compound for the diagnosis and treatment of glioma. Lqh-8/6 and two other natural analogues were chemically synthesized for the first time and evaluated for their ability to label, detect and prevent glioma growth in vitro. We demonstrate that a biotinylated version of Lqh-8/6 allows both the labeling of glioma cell lines and the detection of glioma in brain sections of glioma allograft Fisher rats. Lqh-8/6 has intrinsic anti-invasive properties but is non-toxic to glioma cells. To confer anti-tumor properties to Lqh-8/6, we chemically coupled doxorubicin to the glioma-targeting peptide using click chemistry. To this end, we successfully chemically synthesized Lqh-8/6-azide and doxorubicin-alkyne without impairing the toxic nature of doxorubicin. The toxin-drug conjugate efficiently promotes the apoptosis of glioma cells in vitro. This example contributes to the concept that animal venom peptides constitute exquisite warheads for delivering toxic chemical conjugates, a parallel to the popular concept of antibody-drug conjugates for the treatment of cancer.
PubMed: 36289865
DOI: 10.3390/biomedicines10102605 -
JAMA Otolaryngology-- Head & Neck... Apr 2016Surgical cure of head and neck squamous cell carcinoma (HNSCC) remains hampered by inadequately resected tumors and poor recognition of lesions with malignant potential.... (Observational Study)
Observational Study
IMPORTANCE
Surgical cure of head and neck squamous cell carcinoma (HNSCC) remains hampered by inadequately resected tumors and poor recognition of lesions with malignant potential. BLZ-100 is a chlorotoxin-based, tumor-targeting agent that has not yet been studied in HNSCC.
OBJECTIVE
To evaluate BLZ-100 uptake in models of HNSCC and oral dysplasia.
DESIGN, SETTING, AND PARTICIPANTS
This was an observational study (including sensitivity and specificity analysis) of BLZ-100 uptake in an orthotopic xenograft mouse model of HNSCC and a carcinogen-induced dysplasia model of hamster cheek pouches.
INTERVENTIONS
Various HNSCC xenografts were established in the tongues of NOD-scid IL2Rgammanull (NSG) mice. BLZ-100 was intravenously injected and fluorescence uptake was measured. To induce dysplasia, the carcinogen 7,12-dimethylbenz(a)anthracene (DMBA) was applied to the cheek pouch of Golden Syrian hamsters for 9 to16 weeks. BLZ-100 was subcutaneously injected, and fluorescence uptake was measured.
MAIN OUTCOMES AND MEASURES
The signal-to-background ratio (SBR) of BLZ-100 was measured in tumor xenografts. To calculate the sensitivity and specificity of BLZ-100 uptake, a digital grid was placed over tissue sections and correlative histologic sections to discretely measure fluorescence intensity and presence of tumor; a receiver operating characteristic (ROC) curve was then plotted. In the hamster dysplasia model, cheeks were graded according to dysplasia severity. The SBR of BLZ-100 was compared among dysplasia grades.
RESULTS
In HNSCC xenografts, BLZ-100 demonstrated a mean (SD) SBR of 2.51 (0.47). The ROC curve demonstrated an area under the curve (AUC) of 0.89; an SBR of 2.50 corresponded to 92% sensitivity and 74% specificity. When this analysis was focused on the tumor and nontumor interface, the AUC increased to 0.97; an SBR of 2.50 corresponded to 95% sensitivity and 91% specificity. DMBA treatment of hamster cheek pouches generated lesions representing all grades of dysplasia. The SBR of high-grade dysplasia was significantly greater than that of mild-to-moderate dysplasia (2.31 [0.71] vs 1.51 [0.34], P = .006).
CONCLUSIONS AND RELEVANCE
BLZ-100 is a sensitive and specific marker of HNSCC and can distinguish high-risk from low-risk dysplasia. BLZ-100 has the potential to serve as an intraoperative guide for tumor margin excision and identification of premalignant lesions.
Topics: Animals; Carcinoma, Squamous Cell; Cell Line, Tumor; Coloring Agents; Cricetinae; Head and Neck Neoplasms; Heterografts; Humans; Image Processing, Computer-Assisted; Indocyanine Green; Iodine Radioisotopes; Mesocricetus; Mice; Mice, Inbred NOD; Mouth Neoplasms; Neoplasms, Experimental; ROC Curve; Scorpion Venoms; Squamous Cell Carcinoma of Head and Neck; Tongue
PubMed: 26892902
DOI: 10.1001/jamaoto.2015.3617 -
Scientific Reports May 2016
PubMed: 27220539
DOI: 10.1038/srep26630 -
Experimental Biology and Medicine... Jul 2008Over the past two decades it has become apparent that essentially all living cells express voltage-activated ion channels. While the role of ion channels for electrical... (Review)
Review
Over the past two decades it has become apparent that essentially all living cells express voltage-activated ion channels. While the role of ion channels for electrical signaling between excitable cells is well known, their function in non-excitable cells is somewhat enigmatic. Research on cancer cells suggests that certain ion channels, K+ channels in particular, may be involved in aberrant tumor growth and channel inhibitors often lead to growth arrest. An unsuspected role for K+ and Cl(-) channels has now been documented for primary brain tumors, glioma, where the concerted activity of these channels promotes cell invasion and the formation of brain metastasis. Specifically, Ca2+-activated K+ (BK) channels colocalize with ClC-3 Cl(-) channels to the invading processes of these tumor cells. Upon a rise in intracellular Ca2+, these channels activate and release K+ and Cl(-) ions together with obligated water causing a rapid shrinkage of the leading process. This in turn facilitates the invasion of the cell into the narrow and tortuous extracellular brain spaces. The NKCC1 cotransporter accumulates intracellular Cl(-) to unusually high concentrations, thereby establishing an outward directed gradient for Cl(-) ions. This allows glioma cells to utilize Cl(-) as an osmotically active anion during invasion. Importantly, the inhibition of Cl(-) channels retards cell volume changes, and, in turn, compromises tumor cell invasion. These findings have led to the clinical evaluation of a Cl(-) channel blocking peptide, chlorotoxin, in patients with malignant glioma. Data from this clinical trial shows remarkable tumor selectivity for chlorotoxin. The experimental therapeutic was well tolerated and is now evaluated in a multi-center phase II clinical trial. A similar role for Cl(-) and K+ channels is suspected in other metastatic cancers, and lessons learned from studies of gliomas may pave the way towards the development of novel therapeutics targeting ion channels.
Topics: Brain Neoplasms; Chloride Channels; Glioma; Humans; Ion Channels; Neoplasm Metastasis; Potassium Channels
PubMed: 18445774
DOI: 10.3181/0711-MR-308 -
Science Translational Medicine Mar 2020Although chimeric antigen receptor (CAR) T cells have demonstrated signs of antitumor activity against glioblastoma (GBM), tumor heterogeneity remains a critical...
Although chimeric antigen receptor (CAR) T cells have demonstrated signs of antitumor activity against glioblastoma (GBM), tumor heterogeneity remains a critical challenge. To achieve broader and more effective GBM targeting, we developed a peptide-bearing CAR exploiting the GBM-binding potential of chlorotoxin (CLTX). We find that CLTX peptide binds a great proportion of tumors and constituent tumor cells. CAR T cells using CLTX as the targeting domain (CLTX-CAR T cells) mediate potent anti-GBM activity and efficiently target tumors lacking expression of other GBM-associated antigens. Treatment with CLTX-CAR T cells resulted in tumor regression in orthotopic xenograft GBM tumor models. CLTX-CAR T cells do not exhibit observable off-target effector activity against normal cells or after adoptive transfer into mice. Effective targeting by CLTX-CAR T cells requires cell surface expression of matrix metalloproteinase-2. Our results pioneer a peptide toxin in CAR design, expanding the repertoire of tumor-selective CAR T cells with the potential to reduce antigen escape.
Topics: Animals; Cell Line, Tumor; Glioblastoma; Immunotherapy, Adoptive; Matrix Metalloproteinase 2; Mice; Receptors, Antigen, T-Cell; Scorpion Venoms; T-Lymphocytes; Xenograft Model Antitumor Assays
PubMed: 32132216
DOI: 10.1126/scitranslmed.aaw2672