eMedicineLive

Although extremely rare, Rhabdoid tumor is one of the most rapidly spreading and deadly form of childhood cancers. It usually affects young children between the ages of 2 to 13 though it is commonest in children below 3 years of age. Rhabdoid tumors are most common in the brain and kidneys but have been detected in almost all other parts of the body like heart, lungs, liver and soft tissues, etc. These tumors are generally associated with a poor prognosis.

A characteristic feature of rhabdoid tumors that helps in differentiating them from other poorly differentiated malignant tumors of the brain is the deletion of 22q11 chromosome. Now, researchers at the Albert Einstein College of Medicine, Yeshiva University, led by Ganjam Kalpana, Ph.D., a professor of genetics, microbiology and immunology, have identified a gene which is responsible for the growth of rhabdoid tumors. They have found that Aurora A gene is found in more than normal levels in patients of rhabdoid tumor and may be the target for future potential therapies. These findings have been published in the April 26 issue of Cancer Research.

Scientists have known that mutations in INI1/hSNF5, a tumor suppressor gene can result in rhabdoid tumors. Dr. Kalpana’s team has found that loss of this gene leads to over expression of Aurora A which is vital for the growth of the tumor. The scientists, working on tumor cell lines have shown for the first time that the deletion of INI1/hSNF5 tumor suppressor gene from the cells of rhabdoid tumor causes “de-repression” of Aurora A. If Aurora A gene is stopped from over expressing itself in some manner, the growth of rhabdoid tumor cells can be brought under control.

According to Dr. Kalpana, these findings can be an important breakthrough in the treatment of rhabdoid cancers which seemed untreatable until now. Over-expression of Aurora A has been implicated in the development of melanoma and non- Hodgkin’s lymphoma as well, and now it has been associated with the development of rhabdoid tumors too. Armed with this knowledge, scientists may soon begin trials with Aurora inhibitors for treating rhabdoid tumors in children.

References:
• http://www.cancer.gov/cancertopics/pdq/treatment/child-CNS-ATRT/patient/page1
• http://cancerres.aacrjournals.org/content/71/9/3225.abstract
• http://www.eurekalert.org/pub_releases/2011-05/aeco-erf050511.php