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Turtle, N. F.

Publications and source records attributed to Turtle, N. F..

3 recordsLinked to original sources

Simulating Alpha Particle Doses at the Micron Scale from Prostate Cancer Patient Derived Bone Metastatic Biopsies Using GATE

Radiopharmaceutical therapies are poised to enhance patient care for several currently untreatable metastatic cancers. Radium-223 dichloride citrate is indicated for treatment of bone metastatic castrate resistant prostate cancer, serving as the primary use of alpha particle emitting radium to irradiate bone lesions. Improvements and refinement of such therapies relies on patient centric and micro scale quantification to assess and compare efficacy. Computational modeling and Monte Carlo simulations provide a valuable tool for understanding micro scale phenomena of radiopharmaceutical therapies. Via simulation, we undertake and illuminate dose profiles of radium-223 dichloride treatment, evaluating energy and dose distributions based on primary, patient-derived specimens. A set of four activity distributions were simulated on three patient bone lesion biopsy samples. These simulations validate the novel tool for micron-scale modeling with patient-derived specimens. Ablative dose profiles are shown to be driven by uptake distributions as well as the target tissues microstructure.

bioengineering↗

-Labeled PARP-1 PET Imaging of PSMA Targeted Alpha Particle Radiotherapy Response

MotivationThe growing interest and clinical translation of alpha particle () therapies brings with it new challenges to assess target cell engagement and to monitor therapeutic effect. Noninvasive imaging has great potential to guide -treatment and to harness the potential of these agents in the complex environment of disseminated disease. Poly(ADP) ribose polymerase 1 (PARP-1) is among the most abundantly expressed DNA repair enzymes with key roles in multiple repair pathways - such as those induced by irradiation. Materials and MethodsHere, we used a third-generation PARP1-specific radiotracer, [18F]-PARPZ, to delineate castrate resistant prostate cancer xenografts. Following treatment with the clinically applied [225Ac]-PSMA-617, positron emission tomography was performed and analyzed, along with and correlative autoradiography and histology acquired. Results[18F]-PARPZ was able to distinguish treated from control (saline) xenografts by uptake. Kinetic analysis of tracer accumulation also suggests that the localization of the agent to sites of increased PARP-1 expression is a consequence of DNA damage response. ConclusionsTogether, these data support expanded investigation of [18F]-PARPZ to facilitate clinical translation in the -therapy space.

cancer biology↗

PSMA Expression in the Hi-Myc Model; Extended Utility of a Representative Model of Prostate Cancer for Biological Insight and as a Drug Discovery Tool

Prostate specific membrane antigen (PSMA), also known as glutamate carboxypeptidase II (GCPII), is highly overexpressed in primary and metastatic prostate cancer (PCa). This has led to the development of radiopharmaceuticals for targeted imaging and therapy under current clinical evaluation. Despite this progress, the exact biological role of the protein in prostate cancer development and progression has not been fully elucidated. This is in part because the human PSMA and mouse PSMA (mPSMA) have different patterns of anatomical expression which confound study in the most widely utilized model organisms. Most notably, mPSMA is not expressed in the healthy murine prostate. Here, we reveal that mPSMA is highly upregulated in the prostate and prostate adenocarcinoma in the spontaneous Hi-Myc mouse model, a highly accurate and well characterized mouse model of prostate cancer development. Antibody detection and molecular imaging tools are used to confirm that mPSMA is expressed from early prostatic intraepithelial neoplasia (PIN) through adenocarcinoma.

cancer biology↗