5.24.2010

One small step for man, One giant leap for cancer treatment

(PhysOrg.com)
-'DNA -> RNA -> Protein' is the central dogma of genetics.
-A good way for me to remember complex scientific concepts is to put them in context with something simpler that I understand.
-For me the best context for this genetic concept is comparing it to opening a zip file on the computer.
     -Say you have a zip file (DNA). You cannot simply open the zip file, because it is only useful for storage.
     -In order to open the zip file you must first unzip it (transcription) into a readable file (RNA).
     -Now, when you try and open the unzipped file (RNA) it results in something usable such as a word document, pdf, or mp3 (protein).

-Most anticancer drugs target certain proteins unique to the growth and survival of tumor cells.
-These therapeutics have some limitations because of the 3-D shapes of proteins and the possibility of mutations which 'hide' the protein from the drug without changing the protein's use for the cell.
-A new approach using small interfering RNAs (siRNAs) targets a type of RNA in the cell called messenger RNA (mRNA).

-Unlike protein, mRNA is linear in shape (no bends/folds to hide itself) and has fewer potential mutations.
-This therapy is very exciting because it allows for the indirect targeting of virtually every protein.
-A major hurdle of this therapy (other than getting the siRNA into the cell is targeting only the tumor cell(s).
-Solution = packing the siRNA into nanoparticles which bind only to cancerous cells, then release the siRNA into the bound tumor cell.
-Most importantly, this combined treatment was found to be effective in a human patient during a phase I clinical trial.
-This therapy is being developed for treating cancer, but I can see it being utilized for treating nearly every disease.