Molecular Diagnostic Laboratory

 

Our laboratory is mainly focused on the development of novel noninvasive molecular diagnostic and prognostic tests by discovering new biomarkers for childhood and adult cancers and other diseases.  Our recent studies show that extracellular vesicles (EVs) released by cells are a treasure trove of those biomarkers. EVs are cell membrane bound particles released from different cell and tissue types by an active process into body fluids. Encapsulated within these vesicles are an abundant supply of biomolecules that may provide information about the normal physiological states and disease states of different cell and tissue types.

Research on Extracellular Vesicles in Cancer

It is well known that as compared to normal healthy cells and tissues, cancer cells and tissues release large quantities of EVs into patient's blood stream. In a patient's blood, cancer derived EVs are mixed with EVs derived from healthy cells. One area of our research is to develop methods to separate cancer cell derived EVs from EVs derived from healthy cells in patient blood samples. This will enable us to identify cancer specific biomolecules that can be used to develop noninvasive diagnostic and prognostic assays as well.

We have discovered that a large proportion of extracellular DNA in human blood plasma is localized in EVs. EV derived DNA are highly fragmented but represent the whole human genome. One of our projects is to compare differences in EV derived DNA obtained from healthy people and cancer patients by Next Generation Sequencing (NGS) in order to find disease specific alterations in cancer cell genome. This new information could be used to develop new noninvasive molecular tests.

Another area of our interest is to compare gene expression pattern and miRNA expression patterns in EVs derived from normal cells and cancer cells using microarray and NGS technologies. This will help us to identify novel molecular biomarkers that are either upregulated or downregulated in cancer cells.

Research on Other Inherited Diseases

Our laboratory is currently developing NGS testing panels for some inherited diseases. For example, Usher syndrome is an inherited disease characterized by hearing loss and impairment of vision and balance. This syndrome is diagnosed based on hearing, vision and balance tests. Genetic tests help to confirm diagnosis and decide treatment options.

Since multiple genes are involved in Usher syndrome, it is not practical to develop genetic tests based on traditional Sanger sequencing. NGS technology is a powerful tool that can be used to study many genes simultaneously. Gene analysis using NGS technology is a rapidly developing field and those new developments have greatly contributed to the reduction of the costs associated with those sequencing-based tests. We have undertaken studies to develop an NGS panel to cover all genes that have been implicated in Usher syndrome and a comprehensive hearing loss NGS panel. Newly developed highly consistent and efficient automation technologies will be used to reduce the overall cost and increase testing consistency and accuracy.