Deepak Dinakaran

At A Glance

• Translational research program focused on therapeutic and diagnostic applications of biophotonics in cancer

• Developing polymeric nanoparticles for radiation-activated photodynamic therapy (radioPDT)

• Applying photon absorption remote sensing for rapid molecular diagnostics

• Radiosensitization of CNS malignancies with biophotonics and targeted small molecules

Short Bio

Dr. Dinakaran is a clinician scientist in radiation oncology at the Sunnybrook Research Institute/Odette Cancer Center. He completed his H.BSc at the University of Toronto, MD.CM at McGill University, MEd at the University of British Columbia and PhD at the University of Alberta during his residency as part of the clinician-investigator program. He completed a CNS clinical/postdoctoral fellowship in NCI/NIH under Dr. Kevin Camphausen on radiosensitizer discovery in the lab through to first-in-human trials. His research lab focuses on biophotonics systems for diagnostics and therapeutic applications with radiation. In particular, he is interested in radiation & drug combinations, novel nanoparticle-based therapeutics, and understanding radiotherapy-drug interactions using molecular biomarker analysis.

Research Synopsis

Radiation-activated Photodynamic Therapy (radioPDT)
Photodynamic Therapy (PDT) uses visible light to excite a photosensitizing drug to generate short-lived, highly reactive singlet oxygen locally at the site of disease. This reacts with lipid membranes and macromolecules to induces oxidative stress, vascular damage, inflammation, and cell death. PDT is highly effective in killing cancer cells with minimal toxicity to normal tissue outside the field of the light source. However, due to limited penetrance of light, PDT cannot easily treat deep-seated targets without invasive techniques. Dr. Dinakaran's research program has developed a novel PDT approach using nanoscintillators co-encapsulated with photosensitizers into a nanoparticle that can address these limitations. High energy X-rays penetrate deeply into tissue to stimulate the nanoscintillators, activating the photosensitizer via Forster resonance energy transfer (FRET). Preclinical studies show radioPDT can nominally double the therapeutic effect of radiation alone by adding organelle damage, vascular infarction and acute cell death to radiation's DNA damage effects. Future directions are aimed at translating radioPDT into Phase I clinical trials, and developing nanoparticle variants capable of MRI enhancement for image guidance and selective drug release.

Molecular imaging with Photon Absorption and Remote Sensing
Treating CNS malignancies have significantly advanced with the use of molecular pathology, which can significantly improve clinical care by better stratification, prognostication and predicting disease treatment response. Current molecular diagnostics is limited by costly and lengthy processing steps, need for sufficient tissue sample, and underestimating the heterogeneity of the tumour. A potential solutions, lies in a new imaging technique called Photon Absorption Remote Sensing (PARS) imaging that uses a super-fast pulsed excitation laser and a detection laser to detect how macromolecules within tissue can absorb and dissipate photons. These optical properties are unique to different biomolecules, which allows molecular PARS (M-PARS) to detect molecular characteristics within tissue in near-realtime without any processing or expensive preparation steps. The goal of this line of research is to bring molecular information earlier into the clinical management of patients to enable personalized medicine that can monitor and adapt delivery of treatment in real-time. 

Radiation-activated Photodynamic Therapy (radioPDT)
Photodynamic Therapy (PDT) uses visible light to excite a photosensitizing drug to generate short-lived, highly reactive singlet oxygen locally at the site of disease. This reacts with lipid membranes and macromolecules to induces oxidative stress, vascular damage, inflammation, and cell death. PDT is highly effective in killing cancer cells with minimal toxicity to normal tissue outside the field of the light source. However, due to limited penetrance of light, PDT cannot easily treat deep-seated targets without invasive techniques. Dr. Dinakaran's research program has developed a novel PDT approach using nanoscintillators co-encapsulated with photosensitizers into a nanoparticle that can address these limitations. High energy X-rays penetrate deeply into tissue to stimulate the nanoscintillators, activating the photosensitizer via Forster resonance energy transfer (FRET). Preclinical studies show radioPDT can nominally double the therapeutic effect of radiation alone by adding organelle damage, vascular infarction and acute cell death to radiation's DNA damage effects. Future directions are aimed at translating radioPDT into Phase I clinical trials, and developing nanoparticle variants capable of MRI enhancement for image guidance and selective drug release.

Molecular imaging with Photon Absorption and Remote Sensing
Treating CNS malignancies have significantly advanced with the use of molecular pathology, which can significantly improve clinical care by better stratification, prognostication and predicting disease treatment response. Current molecular diagnostics is limited by costly and lengthy processing steps, need for sufficient tissue sample, and underestimating the heterogeneity of the tumour. A potential solutions, lies in a new imaging technique called Photon Absorption Remote Sensing (PARS) imaging that uses a super-fast pulsed excitation laser and a detection laser to detect how macromolecules within tissue can absorb and dissipate photons. These optical properties are unique to different biomolecules, which allows molecular PARS (M-PARS) to detect molecular characteristics within tissue in near-realtime without any processing or expensive preparation steps. The goal of this line of research is to bring molecular information earlier into the clinical management of patients to enable personalized medicine that can monitor and adapt delivery of treatment in real-time.