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- Bicak, Mesude, et al.
(författare)
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Genetic signature of prostate cancer mouse models resistant to optimized hK2 targeted α-particle therapy
- 2020
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 1091-6490. ; 117:26, s. 15172-15181
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Tidskriftsartikel (refereegranskat)abstract
- Hu11B6 is a monoclonal antibody that internalizes in cells expressing androgen receptor (AR)-regulated prostate-specific enzyme human kallikrein-related peptidase 2 (hK2; KLK2). In multiple rodent models, Actinium-225-labeled hu11B6-IgG1 ([225Ac]hu11B6-IgG1) has shown promising treatment efficacy. In the present study, we investigated options to enhance and optimize [225Ac]hu11B6 treatment. First, we evaluated the possibility of exploiting IgG3, the IgG subclass with superior activation of complement and ability to mediate FC-γ-receptor binding, for immunotherapeutically enhanced hK2 targeted α-radioimmunotherapy. Second, we compared the therapeutic efficacy of a single high activity vs. fractionated activity. Finally, we used RNA sequencing to analyze the genomic signatures of prostate cancer that progressed after targeted α-therapy. [225Ac]hu11B6-IgG3 was a functionally enhanced alternative to [225Ac]hu11B6-IgG1 but offered no improvement of therapeutic efficacy. Progression-free survival was slightly increased with a single high activity compared to fractionated activity. Tumor-free animals succumbing after treatment revealed no evidence of treatment-associated toxicity. In addition to up-regulation of canonical aggressive prostate cancer genes, such as MMP7, ETV1, NTS, and SCHLAP1, we also noted a significant decrease in both KLK3 (prostate-specific antigen ) and FOLH1 (prostate-specific membrane antigen) but not in AR and KLK2, demonstrating efficacy of sequential [225Ac]hu11B6 in a mouse model.
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| 2. |
- Storey, Claire M, et al.
(författare)
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Quantitative In Vivo Imaging of the Androgen Receptor Axis Reveals Degree of Prostate Cancer Radiotherapy Response
- 2023
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Ingår i: Molecular cancer research : MCR. - 1557-3125. ; 21:4, s. 1-9
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Tidskriftsartikel (refereegranskat)abstract
- Non-invasive biomarkers for androgen receptor (AR) pathway activation are urgently needed to better monitor patient response to prostate cancer (PCa) therapies. AR is a critical driver and mediator of resistance of PCa but currently available non-invasive PCa biomarkers to monitor AR activity are discordant with downstream AR pathway activity. External beam radiotherapy (EBRT) remains a common treatment for all stages of PCa, and DNA damage induced by EBRT upregulates AR pathway activity to promote therapeutic resistance. [89Zr]11B6-PET is a novel modality targeting prostate-specific protein human kallikrein 2 (hK2), which is a surrogate biomarker for AR activity. Here, we studied if [&sup89;Zr]11B6-PET can accurately assess EBRT-induced AR activity. Genetic and human PCa mouse models received EBRT (2-50 Gy) and treatment response was monitored by [89Zr]11B6-PET/CT. Radiotracer uptake and expression of AR and AR target genes was quantified in resected tissue. EBRT increased AR pathway activity and [&sup89;Zr]11B6 uptake in LNCaP-AR and 22RV1 tumors. EBRT increased prostate-specific [&sup89;Zr]11B6 uptake in PCa-bearing mice (Hi-Myc x Pb_KLK2) with no significant changes in uptake in healthy (Pb_KLK2) mice, and this correlated with hK2 protein levels. Implications: hK2 expression in PCa tissue is a proxy of EBRT-induced AR activity that can non-invasively be detected using [&sup89;Zr]11B6-PET; further clinical evaluation of hK2-PET for monitoring response and development of resistance to EBRT in real time is warranted.
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