Nucleic Acid Aptamer Selection against Endoglin (CD105) for the Inhibition of Tumor Cells

Vicki Oladoyin

September 18, 2012

FRI: Aptamer

N40B Pool, RNA, CD105

Nucleic Acid Aptamer Selection against Endoglin (CD105) for the Inhibition of Tumors

Abstract:

           Endoglin (CD105) is a cell membrane glycoprotein expressed on cellular lineages within the vascular system and is involved in blood vessel development (Fonsatti 2003). It has been discovered that endoglin may be involved with tumors associated with the vascular endothelium, because endoglin has been found to be over-expressed on proliferating endothelial cells of both peri-and intra-tumoral blood vessels (Fonsatti 2003).  For research purposes, an aptamer against mouse endoglin will be selected via in vitro SELEX (systematic evolution of ligands by exponential enrichment).  Furthermore, the practical implications of using an aptamer selected against endoglin to inhibit the formation of tumors will be discussed.

Specific Aim 1: Identifying an Aptamer Against Endoglin

Indentifying a high affinity and specific RNA aptamer against endoglin would be beneficial, because endoglin is expressed on over-proliferating endothelial cells as represented in Figure 1.  An aptamer selected against endoglin would therefore be useful for diagnosis and possibly the development of a therapeutic drug to inhibit the over-proliferation of tumor cells.

Specific Aim 2: Identifying an Anti-Endoglin Aptamer

            Identifying an anti-endoglin aptamer would be a useful tool for the studying of the functions and processes of the endoglin glycoprotein in the human body and its role in the formation of blood vessels.  This could then lead to a better understanding of angiogenesis, the physiological process involving the growth of new blood vessels from pre-existing vessels (Wahl 2004).

Endoglin (CD105) protein can be purchased from Sino Biological Inc. at a price of $290 per 100ug; its call number is 50407-M08H.  It has a calculated molecular mass of 61.2kDa.  The cost per round will be about $35.50. This amount will allow eight rounds of selection to be performed using 200 pmols of the target per round.  The company's phone number is 86-400-890-9989.

• for a link to the proposal click here
• for a link to the first progress report click here
• for a link to the second progress report click here
• for a link to the final manuscript click here

References

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