New Cell Lines for Anaplastic Thyroid Cancer Created
Mayo Clinic researchers have created a new set of laboratory anaplastic thyroid cancer (ATC) cells, derived from tumors donated by patients. They developed 4 ATC cell lines, each with a different set of molecular mutations driving this aggressive cancer.
Details are published in the August 25 online issue of the Journal of Clinical Endocrinology & Metabolism. The cell-line development project was prompted by researchers at Mayo Clinic when they discovered several years ago that laboratory samples of ATC they were using to help find new treatments were probably some other kind of cancer.
- Up to half of the cell lines that were supposed to originate from patients with this rare thyroid cancer were either colon cancer or melanoma,
- Studies on the newly created cell line reportedly shows detailed molecular fingerprinting that links genetic mutations found in the patients’ tumors to the cell lines that are derived from these tumors,
- If any question arises in the future as to whether these lines have become contaminated by other cancers, researchers can use the Mayo Clinic data to confirm the origin of the cells,
- The study also tested 5 different drugs in these new cell lines for potential benefit,
- The researchers found that all of these agents—everything from an approved cholesterol-lowering agent to experimental transferase inhibitors—reactivated a tumor suppressor gene called RhoB, leading to growth suppression.
Mayo researchers led by Dr. John Copland,PhD, the study’s co-principal author had previously discovered that RhoB function was missing in ATC cells, as it is in some other cancers. Robert Smallridge, MD, also a co-principal author is currently conducting a Phase I trial testing an agent that can turn the tumor suppressor function back on.
Because thyroid cancers are uncommon and anaplastic thyroid cancer is exceedingly rare—fewer than 600 new ATC cases a year in the US. Dr. Smallridge asked every patient having surgery for thyroid cancer at Mayo Clinic for a tumor sample.
Surgeons around the country have sent Laura Marlow, the study’s lead investigator, tumor samples in her quest to create new cell lines for thyroid cancer. Using tumor samples from this collaboration, it took 2 years and several tries to create the 4 new lines. “These cells are very difficult to grow and to maintain because of their chromosomal instability.” Marlow had to derive a new formula for the media that the cells live on in their culture dishes, a recipe that is special for this kind of cancer and which is reproduced in the study publication. The article also identifies multiple genetic and phenotypic tests that will uniquely identify each cell line now and in the future.(HWM and GEN)
