title: Characterization of PI (breast cancer cell special  peptide) in MDA-MB-231 breast cancer cells  and its potential therapeutic applications.
abstract: Gene therapy is one of the most important aspects of molecular targeted therapeutic approaches for tumors. A small molecule targeting carrier plays an important role in this process. PI, a new peptide found in our phage library, has been specifically suggested, combined with the human triple-negative breast cancer cell line MDA-MB‑231, and may be developed as a targeting/individualization therapy strategy to be applied in breast cancer research. In this study, we further investigated whether this peptide could carry exogenous protein to the target cells by forming a fusion peptide. PI-GST and PI-TK were cloned into plasmids and used for expression studies, analyses of PI-mediated protein delivery efficiency, and to investigations into the effect of PI on thymidine kinase/ganciclovir-mediated cytotoxicity. Biodistribution profiles were also investigated in vivo. The results showed the PI fusion protein was expressed correctly in vitro, and could carry GST into the target cells. Under certain conditions, PI-TK sensitizes cells to ganciclovir more efficiently than TK. In vivo there was a trend for increased inhibition of tumor growth with PI-TK when ganciclovir was present. Therefore, our results suggest the potential of PI as a new specific target carrier in breast cancer therapy.
authors.forename: Change
authors.initials: C
authors.lastname: Gao
authors.forename: Min
authors.initials: M
authors.lastname: Hong
authors.forename: Jiwei
authors.initials: J
authors.lastname: Geng
authors.forename: Huahua
authors.initials: H
authors.lastname: Zhou
authors.forename: Jian
authors.initials: J
authors.lastname: Dong
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics; D015153:Blotting, Western; D001943:Breast Neoplasms; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D057846:Cell-Penetrating Peptides / Q000008:administration & dosage* / Q000493:pharmacokinetics; D005455:Fluorescent Antibody Technique; D015774:Ganciclovir / Q000494:pharmacology; D041722:Genes, Transgenic, Suicide; D015316:Genetic Therapy / Q000379:methods*; D064593:Heterografts; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D027361:Organic Anion Transporters; D011993:Recombinant Fusion Proteins / Q000008:administration & dosage* / Q000493:pharmacokinetics; D013937:Thymidine Kinase / Q000008:administration & dosage; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D000970:Antineoplastic Agents; D057846:Cell-Penetrating Peptides; D015774:Ganciclovir; D027361:Organic Anion Transporters; D011993:Recombinant Fusion Proteins; D013937:Thymidine Kinase; C487009:SLCO6A1 protein, human