RNA interfering (RNAi) using
short interfering RNA (
siRNA) is becoming a promising approach for cancer gene
therapy. However, owing to the lack of safe and efficient carriers, the application of RNAi for clinical use is still very limited. In this study, we have developed
cadmium sulphoselenide/
Zinc sulfide quantum dots (CdSSe/ZnS QDs)-based nanocarriers for in vitro gene delivery. These CdSSe/ZnS QDs are functionalized with
polyethyleneimine (PEI) to form stable nanoplex (QD-PEI) and subsequently they are used for
siRNA loading which specially targets human
telomerase reverse transcriptase (TERT). High gene transfection efficiency (>80%) was achieved on two
glioblastoma cell lines, U87 and U251. The gene expression level (49.99 ± 10.23% for U87, 43.28 ± 9.66% for U251) and
protein expression level (51.58 ± 7.88% for U87, 50.69 ± 7.59% for U251) of TERT is observed to decrease substantially after transfecting the
tumor cells for 48 h. More importantly, the silencing of TERT gene expression significantly suppressed the proliferation of
glioblastoma cells. No obvious cytotoxicity from these QD-PEI nanoplexes were observed over
at 10 times of the transfected doses. Based on these results, we envision that QDs engineered here can be used as a safe and efficient gene nanocarrier for
siRNA delivery and a promising tool for future cancer gene
therapy applications.