Raltitrexed-Modified Gold and Silver Nanoparticles for Targeted Cancer Therapy: Cytotoxicity Behavior In Vitro on A549 and HCT-116 Human Cancer Cells.

Two different raltitrexed gold and silver nanoparticles for the delivery of an antitumoral drug into cancer cells were synthesized and characterized. A cysteine linker was used for the covalent bonding of raltitrexed to the surface of nanoparticles. To evaluate the efficacy of the antifolate-derivative nanoparticles, their cytotoxicity was assayed in vitro with A549 human lung adenocarcinoma and HCT-116 colorectal carcinoma human cells. Modified nanoparticles are a biocompatible material, and administration of silver raltitrexed nanoparticles strongly inhibited the viability of the cancer cells; gold raltitrexed nanoparticles do not show any type of cytotoxic effect. The results suggest that silver raltitrexed nanoparticles could be a potential delivery system for certain cancer cells.

New Bicistronic TALENs Greatly Improve Genome Editing.

Genome editing has become one of the most powerful tools in present-day stem cell and regenerative medicine research, but despite its rapid acceptance and widespread use, some elements of the technology still need improvement. In this unit, we present data regarding the use of a new, more efficient type of transcription activator-like effector nuclease (TALEN) for gene editing. Our group has generated bicistronic genes in which classical TALEN coding sequences are linked by 2A elements to different reporter molecules, such as fluorochromes (TALEN-F) or membrane receptors (TALEN-M). This structure results in two proteins transcribed from the same transcript, of which the second (the reporter) can be used as the target for selection by fluorescence-assisted cell sorting (FACS) or magnetic-activated cell sorting (MACS). The application of these new TALEN genes allows a rapid enrichment of cells in which both members of the TALEN pair are active, thus eliminating the need for lengthy selection in culture and laborious characterization of a large number of clones. © 2020 by John Wiley & Sons, Inc. Basic Protocol 1: Generation of new TALENs Basic Protocol 2: Genome editing using TALEN-F Alternate Protocol 1: Generation of TALEN-M Support Protocol 1: mRNA in vitro transcription (IVT) of TALEN-T2A-reporter expression vector Alternate Protocol 2: Editing of primary T cells using TALEN-M Basic Protocol 3: Verifying gene editing Support Protocol 2: Rapid expansion protocol for edited T-cells.