By culturing circulating cancer cells, researchers learn more about tumors' shifting genetic profiles, pointing a way toward personalized treatments.
No two people are the same, and that holds true for cancer patients. The genetic profiles of tumors vary from person to person; what’s more, these profiles are in flux, as tumors acquire new mutations during the course of treatment. These mutations in turn may determine whether or not a drug will be effective. Thus, a “one size fits all” approach is not optimal when cancer cells not only differ among individuals but even within the same individual over time.
It would be helpful, then, if health care professionals could readily obtain a snapshot of the genetic profile of a patient’s tumor at a certain time and take that information into account when determining the next plan of action. Taking a sample from a patient may be difficult or impossible and might yield relatively few cancer cells.
Researchers took advantage of the fact that cancer cells circulate through the bloodstream at a low concentration in patients with solid tumors. The investigators built upon their previous work on isolating these circulating cancer cells by means of excluding regular blood cells. Now, the researchers have found favorable conditions for the cells to multiply in the lab.
By obtaining abundant populations of cancer cells, the researchers were able to undertake a particularly comprehensive analysis of the genetic profiles of tumors from six patients with metastatic breast cancer. The cells at hand also enabled the investigators to test various drugs in the lab, alone and in combination.
This way, the researchers could determine which drugs were effective against which types of mutated cancer cells. For example, the experimenters noted the emergence of a mutation in the ESR1 gene in some of the tumors. The best therapy for estrogen receptor-positive, ESR1 mutants is unknown. The researchers found that a low dose of the drug STA9090 was effective in killing these types of cancer cells. In retrospect this made sense, because STA9090 targets a protein that assists in the stability of mutated proteins.
This proof-of-concept study demonstrated that it may be feasible in the future to use this approach to monitor the ever-changing mutational profiles of a tumor, to learn insights about the underlying biology, and to choose the drugs that are the best weapon against those particular cancer cells. As they say, know your enemy.
It stands to reason that studying disease-state products is useful for understanding the particularities of a disease. HemaCare offers fresh and cryopreserved primary cells and blood components from disease states including cancers such as kidney, breast, and prostate.
1. Yu, M et al. Ex vivo culture of circulating breast tumor cells for individualized testing of drug susceptibility. Science 2014 July 11;345(6193):216.