10/23/2023
By Joanne Gagnon-Ketchen
Prof. Tayyaba Hasan (Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School; Division of Health Sciences and Technology, Harvard University and Massachusetts Institute of Technology) will present "Photodynamic Therapy: A bridge between Science, Engineering and Medicine."
Abstract: Photodynamic therapy (PDT) is a photochemistry-based process resulting from the light activation of chemicals localized at anatomical sites of disease. PDT is approved for specific clinical applications by regulatory agencies worldwide and has inherent selectivity built in it. The first arising from a preferential localization of the PS and second the simultaneous requirement for light to activate any cytotoxic process which can be controlled by confining the volume of tissue exposed to light. A small fraction of the excited state de-energizes via fluorescence thus providing an opportunity to use the same molecule for detection/diagnostics and therapy. As with any therapy, PDT elicits molecular responses that can be exploited to enrich our arsenal of cancer treatment. It involves the excitation of certain chemicals, called photosensitizers (PS) by photons of a specific wavelength to produce reactive species that are toxic to cells The active molecular species produced by such a molecular excitation destroys biological targets in the vicinity. As the complexity of the target disease increases for reasons such as heterogeneity in disease biology or diffuse disease spread over large surface areas, so must the sophistication in PDT planning and application. As we move forward in the field, light and PS delivery become more important. Not the least because the process of photodynamic priming facilitates enhance delivery of conventional chemotherapeutic drugs and makes the microenvironment more conducive to secondary treatments. This has given rise to innovative engineering in light delivery and nanotechnology. This presentation will focus on the challenges associated with applying PDT as a therapeutic and a theranostic modality.
Bio: Tayyaba Hasan, Ph.D. is a Professor of Dermatology at Harvard Medical School and a Professor of Health Sciences and Technology at Harvard-MIT. She is a leader in photochemical and photobiological approaches to treatment and diagnosis of cancer and infection using targeted strategies especially nanotechnology. She is an inventor of the photodynamic treatment of Age-Related Macular Degeneration in the eye, which has been used for millions of patients. She has ~300 publications and over 30 inventions. Hasan leads an NCI-funded multinational Program Project grant focused on image-guided treatment of pancreatic and skin cancers and an international consortium on developing low-cost technologies for image-guided photodynamic therapy of oral cancer in addition to several investigator-initiated programs. Hasan’s contributions to successful translational studies and other discoveries earned her the coveted US National Institutes of Health Pioneer Award in Biomedical Optics Award. She has received 5 Lifetime Achievement awards from leading scientific organizations, including the ICPP, the American Society for Photobiology, the International Photodynamic Association, and the Society of American Asian Scientists in Cancer Research. Recent awards include the Gold Medal Award for Excellence in Photobiological Research from the European Society for Photobiology, and the Gold Medal from the International Photodynamic Association, recognizing her significant career in photodynamic therapy. She has also earned numerous awards for her commitment to mentoring, teaching, and equitable representation in science.