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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. |
- Thorek, Daniel L.J., et al.
(författare)
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Harnessing androgen receptor pathway activation for targeted alpha particle radioimmunotherapy of breast cancer
- 2019
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Ingår i: Clinical Cancer Research. - 1078-0432. ; 25:2, s. 881-891
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: The impact of androgen receptor (AR) activity Results: D-Norgestrel and DHT activated the AR pathway, in breast cancer biology is unclear. We characterized and while 17b-Estradiol did not. Competitive binding for AR tested a novel therapy to an AR-governed target in breast protein showed similar affinity between DHT and D-Norges-cancer. trel, indicating direct AR–ligand interaction. In vivo production Experimental Design: We evaluated the expression of of hK2 was sufficient to achieve site-specific delivery of ther-prototypical AR gene products human kallikrein 2 (hK2) apeutic radionuclide to tumor tissue at >20-fold over back- and PSA in breast cancer models. We screened 13 well-ground muscle uptake; effecting long-term local tumor characterized breast cancer cell lines for hK2 and PSA control. production upon in vitro hormone stimulation by testoster-Conclusions: [225Ac]hu11B6 targeted radiotherapy one [dihydrotestosterone (DHT)]. AR-positive lines were was potentiated by DHT and by D-Norgestrel in murine further evaluated by exposure to estrogen (17b-Estradiol) xenograft models of breast cancer. AR activity in and the synthetic progestin D-Norgestrel. We then evaluated breast cancer correlates with kallikrein-related peptidase-2 an anti-hK2–targeted radiotherapy platform (hu11B6), and can be activated by D-Norgestrel, a common con-labeled with alpha (a)-particle emitting Actinium-225, to traceptive, and AR induction can be harnessed for hK2-specifically treat AR-expressing breast cancer xenografts targeted breast cancer a-emitter radiotherapy. under hormone stimulation.
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| 3. |
- Thorek, Daniel L J, et al.
(författare)
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Internalization of secreted antigen-targeted antibodies by the neonatal Fc receptor for precision imaging of the androgen receptor axis
- 2016
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Ingår i: Science Translational Medicine. - : American Association for the Advancement of Science (AAAS). - 1946-6234 .- 1946-6242. ; 8:367
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Tidskriftsartikel (refereegranskat)abstract
- Targeting the androgen receptor (AR) pathway prolongs survival in patients with prostate cancer, but resistance rapidly develops. Understanding this resistance is confounded by a lack of noninvasive means to assess AR activity in vivo. We report intracellular accumulation of a secreted antigen-targeted antibody (SATA) that can be used to characterize disease, guide therapy, and monitor response. AR-regulated human kallikrein-related peptidase 2 (free hK2) is a prostate tissue-specific antigen produced in prostate cancer and androgen-stimulated breast cancer cells. Fluorescent and radio conjugates of 11B6, an antibody targeting free hK2, are internalized and noninvasively report AR pathway activity in metastatic and genetically engineered models of cancer development and treatment. Uptake is mediated by a mechanism involving the neonatal Fc receptor. Humanized 11B6, which has undergone toxicological tests in nonhuman primates, has the potential to improve patient management in these cancers. Furthermore, cellspecific SATA uptake may have a broader use for molecularly guided diagnosis and therapy in other cancers.
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