Chen and co-workers used this approach with a PLGA-PEG-PLGAthermosensitivehydrogel that safely delivered shRNA against the tumor oncogene PLK1.234 PLK1 shRNA was complexed with a polylysine-modifiedpolyethylenimine, producing a roughly 100 nm particle,235 which is sufficiently large to tune the releaserate based on the porosity of the hydrogel carrier. The gene discussed is PLK1; the disease is neoplasm.