Scientist profiles A-F
Sunnybrook Health Sciences Centre
2075 Bayview Ave., Room T2 167
Administrative Assistant: Jennifer Coccagna
- B.Sc., 1991, biochemistry, McMaster University, Canada
- PhD, 1995, medical biophysics, University of Toronto, Canada
- MD, 2000, University of Toronto, Canada
Appointments and Affiliations:
- Senior scientist, Physical Sciences, Odette Cancer Research Program (director), Sunnybrook Research Institute
- Radiation oncologist, Sunnybrook Health Sciences Centre
- Associate professor, departments of radiation oncology and medical biophysics, University of Toronto
- Ultrasound imaging
- Spectroscopy of cancer therapy responses
Dr. Czarnota is conducting research focused on using ultrasound imaging and spectroscopy at conventional and high frequencies to detect apoptosis and other forms of cell death in response to chemotherapy and radiation therapy. In addition to being a scientist in the imaging discipline he is an MD in the department of radiation oncology with applied research in breast cancer patients. His basic science research interests include studies in biochemistry, chromatin biology, biophysics, medicine and oncology.
Dr. Czarnota, along with his collaborator Dr. Michael Kolios, discovered that ultrasound could be used to detect apoptosis. This finding has since been applied to important questions in oncology and organ transplantation. Our research group has demonstrated that this special form of cell death may be detected using ultrasound imaging and spectroscopy in vitro, in situ, and in vivo. The use of ultrasound to detect apoptosis and other forms of cell death has numerous applications listed below.
Cell and molecular biology:
Despite the use of medical ultrasound for decades, the features inside cells that contribute to ultrasound backscatter at conventional and high frequencies remain unknown. We are systematically probing how subcellular constituents such as DNA, RNA, protein and lipids contribute to backscatter. In particular we are interested in how nuclear and chromatin structure affects ultrasound signals since we have found it to be a dominant structure in the formation of backscatter signals.
Image and spectroscopic analysis:
We are collaboratively investigating a number of spectroscopic parameters for characterizing tumours and tumour responses to chemotherapy and radiation therapy at conventional and high frequencies. We are developing these methods to generate colour-coded ultrasound parameteric maps to aid in assessing tumour responses to therapy. Since these spectroscopic signals are potentially linked to nuclear structure and chromatin structure which differs between normal and neoplastic tissue there is potential to develop our spectroscopic methods not only into a method to track tumour responses but a potentially important diagnostic tool.
Clinical evaluations of ultrasound imaging and spectroscopy:
We are instituting a number of clinical evaluations of our spectroscopic detection of cell death. Our main investigational site is breast cancer patients with large “locally advanced” breast cancers who receive neoadjuvant combined chemotherapy and radiation therapy. We hope to rapidly distinguish responding tumours from those that are non-responding so that the latter may be treated with different chemotherapy regimens or with radiation sensitizers to hopefully improve outcomes.
- Tunis AS, Czarnota GJ, Giles A, Sherar MD, Hunt JW and Kolios MC. Monitoring structural changes in cells with high frequency ultrasound signal statistics. Ultrasound Med Biol. 2005 Aug; 31(8):1041–1049.
- Czarnota GJ. Role of ultrasound in the detection of apoptosis. Eur J Nucl Med Mol Imaging. 2005 May; 32(5):622–632.
- Kolios MC, Czarnota GJ, Lee M, Hunt JW, Sherar MD. Ultrasonic spectral parameter characterization of apoptosis. Ultrasound Med Biol. 2002 May; 28(5): 589–597.
- Czarnota GJ, Kolios M, Abraham J, Portnoy M, Sherar MD, Ottensmeyer FP and Hunt JW. Ultrasound imaging of apoptosis: high resolution non-invasive monitoring of programmed cell death in vitro, in situ, and in vivo. Br J Cancer. 1999 Oct; 81(3):520–527.
- Czarnota GJ, Kolios M, Vaziri H, Benchimol S, Ottensmeyer FP and Hunt JW. Ultrasound biomicroscopy of living, dead, and apoptotic cells. Ultrasound Med Biol. 1997; 23(6):961–965.
Related News and Stories:
- Individualizing breast cancer therapy: New technologies can deliver highly specific information about a therapy’s effectiveness in days, not months; and help women with DCIS decide on the best course of action (from 2016 SRI Magazine)
- Hi-dose re-irradiation helps breast cancer patients who have limited options: Sunnybrook-led report published in Oncotarget (Oct. 16, 2015)
- Terry Fox Foundation supports cancer research: Funding for quantitative ultrasound research for more tailored cancer treatment (Sept. 11, 2014)
- Crowdfunding success for cancer innovation: WaveCheck raises $20,000 in first day through online donations (Oct. 10, 2013),
- Competition spurs high scores: Scientists secure funding with federal agency (July 25, 2013)
- Discoverers' recompense: Scientists recognized for innovation in prostate cancer research (July 18, 2013)
- New use of ultrasound enhances radiation: Research points to bigger treatment impact at lower radiation doses (July 10, 2012)
- In Focus: Image-Guided Sound Waves Will Change Medicine, Here's How (PDF, Sunnybrook Research Institute Magazine, 2010)
- Smarter, Faster, Better: On the Horizon Innovations in Cancer Care (PDF, Sunnybrook Research Institute Magazine, 2009)
- Crowning Tomorrow's Medical Scientists: Annual project competition highlights research talent of SRI's summer students (August 26, 2009)
- Science and Tech Students Lauded: Ontario Graduate Scholarship recognizes science and technology excellence (December 7, 2007)
- Translation in Collaboration - Sunnybrook plans a novel breast cancer treatment: A feature from Research Report 2004-2006