Molecular diagnostics are tests used to detect or analyze small molecules such as DNA or RNA. For cancer, molecular diagnostics are used to detect different types of gene mutations. This can be done using DNA or RNA.
How are molecular diagnostics used for patient care?
Gene mutations can some times aid doctors diagnose a cancer (what kind of cancer), determine who needs additional treatment (prognosis), or select a specific treatment that is more likely to work (predictive for best treatment).
Our team is developing novel molecular diagnostic tests to detect different types of mutations in many genes. These results can be used to potentially identify potential treatments that a patient might benefit from in a clinical trial.
Tumor Heterogeneity and Autopsy Donation
Patients with cancers that have spread to different organs may initially respond favorably to therapies. However, scientists have discovered that not all cancer cells in the patient’s body are alike. This phenomenon is called “tumor heterogeneity,” which causes some cancer cells to become resistant to treatment and is why cancers can recur after treatment. We will obtain samples of cancer cells from different organs of patients who have died from their cancer through research autopsy. We are grateful to our patients for donating their bodies to the cause of cancer research. We will study their genomes to determine how certain cancer cells acquire resistance and use this knowledge to advance the discovery of new cancer drugs.
Microsatellites are regions of repetitive DNA with certain motifs of 1-6 base pairs in length. Inherited or acquired defects in DNA repair can affect the length of microsatellite regions, leading to microsatellite instability (MSI) in cancer cells.
MSI can be used as a biomarker to predict response to treatment with immunotherapy. Our lab developed a novel algorithm called MANTIS to detect MSI in multiple cancer types (this work is funded by a grant from the NCI (2017-2021) and Pelotonia). MANTIS is part of a clinical assay called MSI-Dx that can be applied on tumor samples to identify patients with MSI who may benefit from immunotherapy.
Columbus Dispatch article about a patient who taught us about the MSI marker.
Sameek Roychowdhury, MD, PhD discusses research on "MSI" with Tracy Townsend.