system
Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, OBJECTIVE, METHODS, RESULTS. Meshes: Animals, Bone Marrow, Breast Neoplasms, Camptothecin, Cations, Cell Line, Tumor, Cell Survival, Chemistry, Pharmaceutical, Dose-Response Relationship, Drug, Female, Humans, Injections, Intravenous, Irinotecan, Lipids, Liposomes, Mice, Mice, Inbred BALB C, Mice, Nude, Particle Size, Polyethylene Glycols, Rats, Rats, Sprague-Dawley, Surface Properties, Tissue Distribution, Topoisomerase I Inhibitors, Xenograft Model Antitumor Assays.
user
Do pEG-coated irinotecan cationic liposomes improve the therapeutic efficacy of breast cancer in animals? Context: Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer death among females owing. This study aimed to construct a kind of PEG-coated irinotecan cationic liposomes for investigating its efficacy and mechanism of action in the treatment of breast cancer in preclinical models. Evaluations were performed on the MDA-MB231 breast cancer cells, the xenografted MDA-MB231 cancer cells in Female nude mice and Sprague-Dawley (SD) rat. The liposomes were characterized through assays of cytotoxicity, intracellular uptake, nuclei morphology, antitumor activities, pharmacokinetics and tissue distribution. The zeta potential of PEG-coated irinotecan cationic liposomes was approximately 23 mV. The PEG-coated irinotecan cationic liposomes were approximately 66nm in diameter, significantly increased the intracellular uptake of irinotecan, and showed strong inhibitory effect on MDA-MB231 breast cancer cells. A significant antitumor efficacy in the xenografted MDA-MB231 breast cancer cells in nude mice was evidenced by intravenous administration of PEG-coated irinotecan cationic liposomes. PEG-coated irinotecan cationic liposomes also improved the irinotecan blood circulation time and showed an enhanced drug concentration in tumor.
assistant
PEG-coated irinotecan cationic liposomes had significant inhibitory effect against breast cancer in vitro and in vivo, hence providing a new strategy for treating breast cancer. Final Decision: yes