tachyplesin-peptide--tachypleus-tridentatus and Glioblastoma

The levels of microRNAs (miRNAs) are altered in various diseases including glioblastoma (GBM) and this alteration may have widespread effects on various hallmarks of cancer cells. MiR210 is overexpressed in GBM and functions as an oncogenic miRNA. Anti-miR210 therapy holds great promise but its efficient delivery remains a major challenge. Our work here explores a novel role of Tachyplesin (Tpl), a cell-penetrating antimicrobial peptide, as a nanocarrier for anti-miR210. Tpl electrostatically interacts with anti-miR210 at 1:25 and 1:50 (anti-miR:Tpl) weight ratios to form a complex and efficiently delivers anti-miR210 inside GBM cells cultured as 2D and 3D spheroid model. Treatment of GBM cells with the complex significantly inhibited miR210 levels (~90%), proliferation, migration and spheroid formation ability and induced apoptosis as evident by increased levels of caspase 3/7 and ROS. GBM cells pre-treated with anti-miR210:Tpl complex were also found to be sensitive to TMZ mediated action. Uptake of the complex in GBM cells induced the levels of miR210 targeted tumor suppressor genes, NeuroD2 and HIF3A. Overall, our work reveals a novel and efficient miRNA delivery ability of Tpl in glioma cells, holding a great promise for treatment of GBM and potentially for other cancers.

Topics: Antagomirs; Antimicrobial Cationic Peptides; Antineoplastic Agents; Antineoplastic Agents, Alkylating; Apoptosis; Brain Neoplasms; Caspase 3; Caspase 7; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cell-Penetrating Peptides; DNA-Binding Proteins; Drug Carriers; Drug Compounding; Gene Expression Regulation, Neoplastic; Glioblastoma; Humans; MicroRNAs; Peptides, Cyclic; Reactive Oxygen Species; Signal Transduction; Temozolomide

Tachyplesin I is a cationic peptide isolated from hemocytes of the horseshoe crab and its anti-tumor activity has been demonstrated in several tumor cells. However, there is limited information providing the global effects and mechanisms of tachyplesin I on glioblastoma multiforme (GBM). Here, by using two complementary proteomic strategies (2D-DIGE and dimethyl isotope labeling-based shotgun proteomics), we explored the effect of tachyplesin I on the proteome of gliomaspheres, a three-dimensional growth model formed by a GBM cell line U251. In total, the expression levels of 192 proteins were found to be significantly altered by tachyplesin I treatment. Gene ontology (GO) analysis revealed that many of them were cytoskeleton proteins and lysosomal acid hydrolases, and the mostly altered biological process was related to cellular metabolism, especially glycolysis. Moreover, we built protein-protein interaction network of these proteins and suggested the important role of DNA topoisomerase 2-alpha (TOP2A) in the signal-transduction cascade of tachyplesin I. In conclusion, we propose that tachyplesin I might down-regulate cathepsins in lysosomes and up-regulate TOP2A to inhibit migration and promote apoptosis in glioma, thus contribute to its anti-tumor function. Our results suggest tachyplesin I is a potential candidate for treatment of glioma.

Topics: Antigens, Neoplasm; Antimicrobial Cationic Peptides; Antineoplastic Agents; Apoptosis; Cathepsins; Cell Line, Tumor; Cell Movement; DNA Topoisomerases, Type II; DNA-Binding Proteins; Down-Regulation; Glioblastoma; Glioma; Glycolysis; Humans; Lysosomes; Peptides, Cyclic; Poly-ADP-Ribose Binding Proteins; Proteome; Proteomics; Up-Regulation