EXCEED THE SPACE PROVIDED. With the advent of anti-angiogenic cancer therapies, effective treatment will require imaging techniques and other surrogates that can establish the optimal dose, provide an early assessment of efficacy, and reduce toxicity associated with systemic delivery of hydrophic drugs. Ultrasound can play a major role in both the assessment of therapeutic efficacy and the improvement of therapeutic delivery. While molecular imaging will be important for understanding angiogenesis and anti-angiogenic therapies, ultrasound can continually evaluate the cumulative effects of biochemical pathway changes on the resulting vascular structure and function. Over the past four years of this project, a new contrast-assisted ultrasound imaging technique has been developedthat can assess angiogenesis through an estimate of microvascular flow rate and density in tumors. The ultrasound technique is unique in that phase inversion and subharmonic acquisition are combined to achieve a clear image of an ultrasound contrast agent, and its motion over time. As a result, a contrast agent to tissue ratio exceeding 27 dB is achieved. Preliminary studies in a rat tumor model have shown that microvascular density and flow rate can be estimated over time, and the resulting map of viable tumor volume correlates with histology. Tumors that reach 1-3centimeters in diameter demonstrate heterogeneousperfusion and include regions with a blood velocity less than 1 mm/s. Human studies of the performanceof this new technique during established chemotherapy will be conducted in this renewal. Pre- clinical studies with new anti-angiogenic drugs will also be conducted in a cross-modality study to create spatial maps of flow rate, vascular density, vascular permeability, and glucose metabolism, using ultrasound, PET, and CT. In implanted rat and spontaneous dog tumor models, a small molecule inhibitor of VEGF, bFGF, and PDGF receptor tyrosine kinase activity is the anti-angiogenic drug that will be applied. As correlates, P53, bFGF, and VEGF expression and apoptosis and cell proliferation will be evaluated. The resultingflow, permeability, and metabolic data will be used to create measures that predict the success or failure of a therapy. Since these hydrophobicdrugs are now suspended in Cremophor for human use, a final aim is to develop acoustically-activated drug delivery vehicles that provide an alternative to the toxicity of Cremophor. PERFORMANCE SITE ========================================Section End===========================================
| Hu, Xiaowen; Zheng, Hairong; Kruse, Dustin E et al. (2010) A sensitive TLRH targeted imaging technique for ultrasonic molecular imaging. IEEE Trans Ultrason Ferroelectr Freq Control 57:305-16 |
| Pollard, Rachel E; Dayton, Paul A; Watson, Katherine D et al. (2009) Motion corrected cadence CPS ultrasound for quantifying response to vasoactive drugs in a rat kidney model. Urology 74:675-81 |
| Qin, Shengping; Kruse, Dustin E; Ferrara, Katherine W (2008) Transmitted ultrasound pressure variation in micro blood vessel phantoms. Ultrasound Med Biol 34:1014-20 |
| Zheng, Hairong; Dayton, Paul A; Caskey, Charles et al. (2007) Ultrasound-driven microbubble oscillation and translation within small phantom vessels. Ultrasound Med Biol 33:1978-87 |
| Pollard, Rachel E; Broumas, Amy R; Wisner, Erik R et al. (2007) Quantitative contrast enhanced ultrasound and CT assessment of tumor response to antiangiogenic therapy in rats. Ultrasound Med Biol 33:235-45 |
| Sun, Yang; Kruse, Dustin E; Ferrara, Katherine W (2007) Contrast imaging with chirped excitation. IEEE Trans Ultrason Ferroelectr Freq Control 54:520-9 |
| Qin, Shengping; Ferrara, Katherine W (2007) The natural frequency of nonlinear oscillation of ultrasound contrast agents in microvessels. Ultrasound Med Biol 33:1140-8 |
| Borden, Mark A; Martinez, Gary V; Ricker, Josette et al. (2006) Lateral phase separation in lipid-coated microbubbles. Langmuir 22:4291-7 |
| Sun, Yang; Zhao, Shukui; Dayton, Paul A et al. (2006) Observation of contrast agent response to chirp insonation with a simultaneous optical-acoustical system. IEEE Trans Ultrason Ferroelectr Freq Control 53:1130-7 |
| Qin, Shengping; Ferrara, Katherine W (2006) Acoustic response of compliable microvessels containing ultrasound contrast agents. Phys Med Biol 51:5065-88 |
Showing the most recent 10 out of 27 publications
