Cell-Free Circulating Tumor DNA
Accomplished researcher Madhu Kumar has contributed to recent developments in cancer screening and diagnostics. Madhu Kumar’s work centers on cancer therapy and the applications of DNA in cancer identification.
Researchers have been in pursuit of a reliable cancer biomarker for many years. The variable and mutative nature of cancer made this difficult until a few years ago. Now, scientists are using DNA from tumors to help identify the presence of cancer faster.
As tumor cells naturally die off, they release bits of their DNA into the patient’s bloodstream. These pieces are known as cell-free circulating tumor DNA, or ctDNA. These particles make it easier to find cancer even when a biopsy is not practical.
Scientists first looked at 187 patients who had 17 different varieties of cancer. In addition to finding ctDNA mutations in some patients’ blood, researchers discovered that there is a correlation between cancer stage and ctDNA concentration. This suggests that ctDNA testing can help screen for cancer at any stage, and could help physicians monitor tumors throughout treatment.
Immune checkpoint therapies
A graduate of Massachusetts Institute of Technology, Madhu Kumar recently served as a scientific advisor at Wilson Sonsini Goodrich and Rosati. Madhu Kumar specializes in molecular biology and in recent years has been interested in cancer-related topics including immune checkpoint therapy.
Immune checkpoint therapy as a discipline has seen significant clinical developments throughout the years and is seen as a new weapon to curb cancer. In clinical trials where this therapy has been utilized, a considerable number of patients with cancer have experienced long-term remission.
This therapy mainly relies on a natural component of the body: the immune system. A vital component of the immune system is the ability to recognize normal and foreign cells, thus giving the immune system an idea which cells to attack. In order to do this, the immune system uses checkpoints, a term used for molecules found on certain immune cells that have to be either activated or inactivated in order to trigger an immune response.
Cancer cells can sometimes use these checkpoints to hide from the body’s immune system, so the main idea behind immune checkpoint therapy is to inhibit these checkpoints and boost the immune response against cancer cells.
Immune checkpoint therapies
Dr. Madhu Kumar is an alumnus of MIT, where he earned his PhD in biology. Since then, Madhu Kumar has pursued research on the diagnosis and treatment of cancers and maintains a particular professional interest in immune checkpoint therapies.
When the human body is invaded by disease, whether caused by a bacterium, parasite, virus, fungus, or cancer cell, it triggers a reaction in certain immune cells, known as T cells, which, in turn, produce an immune system response. The T cells are triggered by the activation (or deactivation) of molecules on their surface, called checkpoint molecules. Many cancers use these checkpoint molecules to avoid triggering an immune system response. One of these molecules, known as PD-1 or PD-L1, tells T cells to leave a given cell alone, and some cancers have large amounts of PD-L1, which helps them avoid attack.
Immune checkpoint therapies target molecules such as PD-L1 by introducing antibodies to the molecule in the vicinity of the cancer. This boosts the immune response to cancers and has had promising results in treating cancers such as melanoma of the skin, non-small-cell lung cancer, kidney cancer, and Hodgkin’s lymphoma.