Antisense is a molecule of DNA or RNA which is developed in the laboratory and binds to its complementary sequences of nucleotides in the body stopping their function. Their main goal is to disable the genes which are responsible for causing diseases in the body. These genes are responsible for producing the unwanted proteins in the body. Antisense DNA or RNA bind to these genes and do not allow them to produce such disease causing proteins. It is possible that this Antisense may bind to the proteins or genes which are working properly in the body and stop their function. It will result in causing the side effects of the Antisense techniques.
Antisense therapy is a method of treating different diseases particularly cancer with Antisense oligonucleotides. In this therapy, the small pieces of DNA or RNA are developed in the laboratory and have the ability to bind to the RNA molecules in the body. This binding of the molecules blocks the disease causing genes to develop its protein. Many types of cancers are treated with this therapy. This therapy is also called as Antisense oligonucleotide therapy.
Cancer and Antisense Therapy:-
Cancer is a deadly disease and scientists are using many techniques to treat the cancerous cells and finding cure for this disease. Antisense therapy is one of the methods for treating cancer. Main function of this therapy so far is to stop the production of protein which progresses the growth of cancer by binding the Antisense DNA or RNA to the binding nucleotide sequences of the cancerous cells. The therapy uses such mechanism of protein binding because it is believed that certain proteins are involved in the formation of malignancy.
Mode of action of Antisense Therapy:-
To treat cancer, scientists have made use of the 20 nucleotides which are specially designed of mRNA sequences. These sequences code the complementary sequences which bind to the targeted proteins. Bcl-2, H-ras and PKC-alpha are some of 20 proteins which are targeted with the complementary Antisense nucleotide sequences of mRNA. Other proteins along with the above mentioned proteins are responsible for the growth of many types of cancers in the human body. They also develop the functions of cancerous cells and make them mutated stopping them from functioning in a positive way. These proteins are then treated with the Antisense therapy. When the nucleotides developed in the laboratory bind to these proteins, they make a heteroduplex. This heteroduplex is formed according to the Watson and Crick method. When the duplex is formed, it blocks the protein from undergoing the process of translation and their further growth. An enzyme which is used in this whole process is Rnase H. this enzyme has the ability to bind to the heteroduplex and helps to cleave the mRNA. This is how the mRNA sequence becomes intact. Through similar mechanism, the oligonucleotides move further and start seeking other proteins with cancerous properties. When they found such proteins, they start their mechanism in the same way and block their activity.
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