Gold nanoparticles
Gold nanoparticles (GNPs) can be used not only as a delivery vehicle but
also as a therapeutic agent (Hashemi Goradel et al., 2018; Negahdari,
Darvishi, & Saeedi, 2019). In several studies, GNPs have been used as
effective siRNA carriers, as they encompass various suitable
characteristics including surface plasmon resonance property, easily
controllable size and shape, and easy modification with other molecules
(Y. Gao, Liu, & Li, 2011). GNPs exhibit effective gene knockdown with
no detectable toxicity and off-target effects. Recently Gold
Nanoclusters (GNCs) with fluorescent tags have gained more attention
because of their unique properties. In addition to their ultra-small
size, GNCs have fluorescence emission from near-infrared to the visible
region (Zheng, Lai, Liu, Jiang, & Wang, 2017).
Perineural invasion is one of the most important pathologic
characteristics of pancreatic cancer (Bapat, Hostetter, Von Hoff, &
Han, 2011). NGFs (nerve growth factors) are crucial regulators of the
tumor-induced neurogenesis and their overexpression has been associated
with pancreatic cancer (Z. Zhu et al., 2002). Recently Lei et al .
(Lei et al., 2017) aimed to develop GNCs to deliver NGF siRNA
(GNC–siRNA) in pancreatic cancer. The results showed high silencing of
NGF gene and suppression of tumor progression in three pancreatic tumor
models. The GNC–siRNA conjugate showed high stability of siRNA in
serum, improved siRNA circulation lifetime in blood, increased cellular
uptake, and no apparent toxicity.
Yin et al . (Yin et al., 2015) used layered structure of gold
nanorods (AuNR) with anionic PSS polymer coating to gravitate
doxorubicin and on the other hand, cationic PAH polymer was used to take
up K-ras siRNA (AuNRs/DOX/K-ras). This compound inhibits tumor growth
for at least 25 days through the controlled release of doxorubicin and
K-ras siRNA in cancer cells and subsequent laser light exposure.