Cell-Based Anticancer Drug Delivery Systems

Most explored approaches to developing cell-based drug delivery systems (DDSs) are encapsulation of the drug into the cells, cell surface modification, genetic modification of cells to secrete desired therapeutic proteins, and generating new biosynthetic systems. Tumor-tropism of mesenchymal stem cells (MSCs), as demonstrated in many studies, can be coupled with appropriate engineering with anticancer genes to enable their employment in anticancer therapy. Furthermore, MSCs can be loaded with nanoparticles (NPs), providing transport across the blood-brain barrier and accumulation of anticancer agent at the tumor site. Another attractive cell type for DDS are dendritic cells (DC), monocytes and macrophages because of their ability to accumulate in large numbers at hypoxic sites of the tumors. To this moment, exosomes are very attractive and investigated cellular entities that are used to be loaded with RNA, proteins, or other small molecules, including anticancer agents. Some of the above-mentioned cells can also be used as membrane sources in the production of anticancer delivery systems. A number of recent research papers and patents in this field are evidence of the growing interest in cell-based DDSs. In this chapter, we summarize recent developments in the field, present a newly established methodology and approaches, give an overview of the recently published inventions (patent databases FPO and Delphion were searched to locate newly published patents: US20150079631, WO2015058148A1, US20160220613, etc.), and discuss further possible developments. Further expansion in this field is expected, although limitations in design and use of DDSs exist and must be overcome before these innovative formulations can reach clinical trials and marketing authorization.

Keywords: Anticancer agents, anticancer therapy, cell membrane vesicles, dendritic cells, drug delivery systems, exosomes, genetic engineering, mesenchymal stem cells, nanoparticles, recent patents.