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


           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.


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Gwen Stovall said...

Dear Vicki,
Here are some thoughts...
1. please include the molecular weight & cost per a round of your target in the abstract.
2. consider putting CD105 in the title ...
3. Please pick-up the Sino order we just dropped off at UT procurement, as it appears we might already have CD105 in the lab. I contacted the previous student that worked on it to find out the locations of the protein.

See you on Tuesday!

Gwen Stovall said...

Dear Vicki,
Take 2 ... thanks for stopping by again ...

1. please look at Elena's sol'n today to see if you have enough. Please see my 9/7/12 email on aliquoting the 20 uM CD105 sol'n. And - let me know if we need to order more.
2. please consider reorg, such that a problem is introduced followed by an aptamer solution to hte problem. And - pull only those details that best support your story. Save the extraneious details for the intro in the full proposal.
3. reconsider specific aim #1 - identify an aptamer
4. reconsider specific aim #2 - application of an aptamer ... perhaps as a localization tool & to monitor levels of expression.
5. for the figure - does it support your story? tell me what the abbreviations mean. Perhaps modify the figure to better relate (or only show) the areas you're intereated in.
6. for the figure - get rid of "adapted from"
7. please consider making your own figure.
8. citations - please consider other ref instead of the Sino Biologicals website. Primary litereature is better.
9. citation - consider supportive ref for the HHT foundation website.

Good abstract.

Thank you,