Molecular switch that allows TN breast cancer cells to grow

This looks like some further research into microRNAs (miRNAs) that Yale researchers have been doing to shut off genes (switches) that cause and promote lung cancer.

It is known by Laboratory Oncologists that on-off switches and back up switches constitute the controls of cancer. When one of these switches stops working and a cell short-circuits, cancer results, and more importantly, metastasis can start.

The stretches of DNA that we call genes are only a very small piece of what makes the body work. Much more important is the stuff in between the genes.

Most of the changes that affect cancer don't lie in the genes themselves but in as many as 40 million different switches that are controlling these genes, turning them on and off in complex and subtle ways.

In other words, the genome is loaded with gene controlling switches.

Each gene provides the code for a single protein. The proteins are the building blocks of cells, and the products made by the cells, from compounds called growth factors to signal-carrying chemicals.

An intermediary genetic structure called RNA carries this information. That RNA generates the 40 million switches that can affect how and when many things happen within the cells.

Again, Laboratory Oncologists know the nuances of human biology encompass the epigenetic, siRNA, pseudogene, non-coding DNA and protein kinetics that ultimately characterize the human phenotype.

For all these reasons, the simple measurement of gene sequences cannot accurately predict biological behavior. Genes do not make us what we are, they only (sometimes) permit us to become what we are, with the vagaries of transcription and translation lying between.

With the discovery of post-transcriptional silencing, widespread involvement of microRNAs (miRNAs) was thought to be the magic bullet against multiple diseases. However, several hurdles, ranging from targeted delivery to side effects still have to be resolved.

In contrast to siRNAs, miRNAs have only been used reluctantly in clinical settings. Reasons for this might be that miRNAs are able to target more than one signaling cascade, bearing potential side effects in other organs and affecting their therapeutic efficacy.

http://www.eurekalert.org/pub_releases/2013-01/cshl-csd010713.php