The Journal
including several essential amino acids. The L-
type amino acid transporter 1 (LAT1) is
overexpressed to support cell growth in
malignant tumors. Double-stranded RNA-
mediated RNA interference (SiRNA) analysis
can be used in a wide variety of eukaryotes to
induce the sequence-specific inhibition of gene
expression. In a current study RNAi has been
found very successful for silencing LAT1
expression on the KB human oral squamous
cell carcinoma.
Steps in RNAi therapeutic development
i. The initial step in this therapy is proper
identification of the target gene which can be
selected from various prime oncogenes,
antiapoptotic genes or tumor promoting genes
along with growth and angiogenic factors or
their receptors.
ii. The next step is the designing of siRNA
sequences to achieve maximum efficiency.
Adata processing algorithm that searches
through the DNA or RNA sequences can be
used for fulfilling the required criteria and
displaying the resulting RNAi candidates
ranked in their hierarchy of fit to the user
supplied rule set(10).
iii. Depending on the position and sequence of a
given siRNA, specificity can be achieved.
iv. The final step is the delivering of siRNA into
the cells and organisms in a whole. Various
successful delivery systems are available at
present (refer fig.) viz.
a) Direct delivery - Though it is a widely used
technique yet it has less potentiality than the
vector based delivery system.
b) Vector based delivery - Both plasmid and
viral vectors are technically more stable, potent
and provide prolonged gene silencing.
c) Nanoparticle based delivery system - It is one
of the most recently proposed system which
provide efficient specificity in the delivery of
siRNA. In this technique large number of
nanoparticles can be loaded into a protected
environment followed by targeting them to the
cancer cells which can be taken up efficiently by
those cells and release RNA molecules into
interior of the cells.
Fig : siRNA delivery methods (GowharShafi)
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Vol. 14 No. 1
Jan-Apr 2018