The Journal
Expediencies and Drawbacks of RNAi Therapy
Expediencies
i . It is a natural pathway to gear up the creation of new class of innovative medicines that can be further designed to be highly potent for treating variety of diseases . ii . It is capable of targeting any given protein thereby eliminating the key limitation of traditional medicines that can only target certain classes of proteins . iii . It enables forthright identification of appropriate drug candidates using siRNAs that can be designed eventually to be active across a wide range of species . iv . It has the ability to selectively deplete a specific protein of interest in cultured cells using siRNAs , plasmids and viral vectors . v . The timing and extent of the gene silencing can be controlled . Hence theessential genes can be silenced at any stages of growth and this approach provides a great degree of flexibility .
Drawbacks
i . The direct introduction of chemically synthesized siRNAs into the cells is limited by the short-lived nature of their transient gene silencing effects and their relative instability . ii . Though a high degree of specificity is associated with RNAi yet some effects have been observed that are independent of the specific gene targeted for silencing . iii . Nucleic acid-based gene-silencing molecules may have effects on genes that are not considered targets and these off-target effects are due to similarities in nucleic acid sequences . iv . Thespecificityof RNAi-mediated degradation of homologous mRNAmakes this strategy highly prone to thedevelopment of resistance , as simple changes in targetsequences may make previously effective siRNA triggers absolutely impotent .
v . The targeting of proteins with a long half-life may result in therapeutic failure despite successful gene silencing , since silencing at the transcript level does not affect pre-existing proteins .
Conclusion
In India , an estimated number of people living with oral cancer is about 1 million , approximately 50 thousand oral cancer related deaths occur every year at the mean age of 50 years . The ( 5 year ) survival rate of patients with early stage oral cancer is 82 % and that of advanced stages is 27 % on an average . Keeping the above mentioned facts in mind we can infer that there is a burning necessity of improved health education and oral health awareness amongst the people in order to fight oral cancer . This statistics has not significantly changed during the last two decades due to lack of early diagnosis , deficiencies in implementation of preventive measures and most importantly , inadequacy in the treatment procedures . Hence the recent discoveries owing to RNAi-based methods might prove to be a elixir to the society and subsequently , is going to become a method of choice and an economically novel way of genetic ablation that holds massive hope for improving the ability to un-ravel the complex regulatory pathways that control the cellular behavior in individuals suffering from oral cancer .
37 Vol . 14 No . 1 Jan-Apr 2018