Chemical Sciences Seminars

Picturing the future of healthcare through molecular imaging

by Dr. Sanhita Sinharay (MD Anderson Cancer Center, The University of Texas)

Tuesday, August 20, 2019 from to (Asia/Kolkata)
at AG-69
Description
In vivo molecular imaging has the unique advantage of noninvasively assessing cancer metabolism or providing functional real-time information relative to obtaining ex vivo pathological information from tissue biopsies. Two important molecular imaging modalities are Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET).
The first part of the presentation will focus on my research in the development of multiple diamagnetic MRI contrast agents and MRI methods that exploit Chemical Exchange Saturation Transfer (CEST) for the detection of enzyme activity (an important cancer biomarker) within in vivo tumor models of ovarian, colon and pancreatic cancers. This description will also demonstrate CEST MRI methods that have been used to correlate enzyme activity with tumor aggressiveness; to support planning for surgical resection of solid tumors; and to evaluate the early response to enzyme inhibitor treatments.  In conclusion, the first part of the talk represents a new paradigm for molecular imaging that can be translated to the radiology clinic to improve early diagnoses of cancer.
The second part of the presentation will focus on my contribution to the field of molecular imaging of several infectious diseases such as HIV/SIV, cerebral malaria (CM), Ebola virus disease, and Marburg hemorrhagic fever, using both MRI and PET imaging modalities. The overarching goal of these studies was to develop neuroimaging biomarkers that are useful for detecting CNS involvement prior to display of clinical symptoms. These studies with a transgenic rat model and SIV rhesus macaque models have identified dopaminergic and serotonergic neurotransmitter biomarkers and have evaluated the role of neuroinflammation in an SIV-model of encephalitis. In a related study with a CM mouse model, we used MRI to evaluate the neuropathology of the disease.  We demonstrated, for the first-time, that reversal of clinical symptoms such as edema can occur with a glutamine antagonist, JHU-083, thus suggesting a possible drug candidate for CM therapy. These studies hope to convey to the audience the growing importance of molecular imaging in unraveling early details of the disease pathology, and to recognize potential opportunities for treatment for these diseases.
The remaining talk will focus on harnessing molecular imaging techniques such as MRI for evaluating other biomarkers of the tumor microenvironment such as extracellular tumor pH, as well as new imaging modalities such as Photoacoustic tomography for improvement in cancer surgery.