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Romiani A, Simonsson K, Pettersson D, Al-Awar A, Rassol N, Bakr H, Lind D, Umapathy G, Spetz J, Palmer R, Hallberg B, Helou K, Forssell-Aronsson E. Comparison of 177Lu-octreotate and 177Lu-octreotide for treatment in human neuroblastoma-bearing mice. Heliyon 2024; 10:e31409. [PMID: 38826727 PMCID: PMC11141386 DOI: 10.1016/j.heliyon.2024.e31409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 05/01/2024] [Accepted: 05/15/2024] [Indexed: 06/04/2024] Open
Abstract
Background Patients with high-risk neuroblastoma (NB) have a 5-year event-free survival of less than 50 %, and novel and improved treatment options are needed. Radiolabeled somatostatin analogs (SSTAs) could be a treatment option. The aims of this work were to compare the biodistribution and the therapeutic effects of 177Lu-octreotate and 177Lu-octreotide in mice bearing the human CLB-BAR NB cell line, and to evaluate their regulatory effects on apoptosis-related genes. Methods The biodistribution of 177Lu-octreotide in mice bearing CLB-BAR tumors was studied at 1, 24, and 168 h after administration, and the absorbed dose was estimated to tumor and normal tissues. Further, animals were administered different amounts of 177Lu-octreotate or 177Lu-octreotide. Tumor volume was measured over time and compared to a control group given saline. RNA was extracted from tumors, and the expression of 84 selected genes involved in apoptosis was quantified with qPCR. Results The activity concentration was generally lower in most tissues for 177Lu-octreotide compared to 177Lu-octreotate. Mean absorbed dose per administered activity to tumor after injection of 1.5 MBq and 15 MBq was 0.74 and 0.03 Gy/MBq for 177Lu-octreotide and 2.9 and 0.45 Gy/MBq for 177Lu-octreotate, respectively. 177Lu-octreotide treatment resulted in statistically significant differences compared to controls. Fractionated administration led to a higher survival fraction than after a single administration. The pro-apoptotic genes TNSFS8, TNSFS10, and TRADD were regulated after administration with 177Lu-octreotate. Treatment with 177Lu-octreotide yielded regulation of the pro-apoptotic genes CASP5 and TRADD, and of the anti-apoptotic gene IL10 as well as the apoptosis-related gene TNF. Conclusion 177Lu-octreotide gave somewhat better anti-tumor effects than 177Lu-octreotate. The similar effect observed in the treated groups with 177Lu-octreotate suggests saturation of the somatostatin receptors. Pronounced anti-tumor effects following fractionated administration merited receptor saturation as an explanation. The gene expression analyses suggest apoptosis activation through the extrinsic pathway for both radiopharmaceuticals.
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Affiliation(s)
- A. Romiani
- Department of Medical Radiation Sciences, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - K. Simonsson
- Department of Medical Radiation Sciences, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - D. Pettersson
- Department of Medical Radiation Sciences, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - A. Al-Awar
- Department of Medical Radiation Sciences, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - N. Rassol
- Department of Medical Radiation Sciences, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - H. Bakr
- Department of Medical Radiation Sciences, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - D.E. Lind
- Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - G. Umapathy
- Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - J. Spetz
- Department of Medical Radiation Sciences, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - R.H. Palmer
- Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - B. Hallberg
- Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - K. Helou
- Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - E. Forssell-Aronsson
- Department of Medical Radiation Sciences, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg, Sweden
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Elvborn M, Shubbar E, Forssell-Aronsson E. Hyperfractionated Treatment with 177Lu-Octreotate Increases Tumor Response in Human Small-Intestine Neuroendocrine GOT1 Tumor Model. Cancers (Basel) 2022; 14:cancers14010235. [PMID: 35008397 PMCID: PMC8750112 DOI: 10.3390/cancers14010235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 12/29/2021] [Accepted: 12/29/2021] [Indexed: 02/01/2023] Open
Abstract
Simple Summary Neuroendocrine tumors are slow growing and initially associated with vague symptoms and, therefore, often spread in the patient’s body at diagnosis, leading to a poor prognosis without means of curation through surgery. Although tumor-targeting treatments exist and are used in clinics, they are not fully optimized. The aim of this study was to test different dosages and time intervals of the radioactive pharmaceutical 177Lu-octreotate. We found that dividing a dosage into several portions and administering it at short time intervals resulted in a stronger tumor reduction and/or prolonged time for regrowth in mice than if given as a single dose. The biggest differences were seen in the lower dosage levels of the study. The findings indicate that there is clear room for improvements in the treatment of neuroendocrine tumors with 177Lu-octreotate. Abstract Radionuclide treatment of patients with neuroendocrine tumors has advanced in the last decades with favorable results using 177Lu-octreotate. However, the gap between the high cure rate in animal studies vs. patient studies indicates a potential to increase the curation of patients. The aim of this study was to investigate the tumor response for different fractionation schemes with 177Lu-octreotate. BALB/c mice bearing a human small-intestine neuroendocrine GOT1 tumor were either mock treated with saline or injected intravenously with a total of 30–120 MBq of 177Lu-octreotate: 1 × 30, 2 × 15, 1 × 60, 2 × 30, 1 × 120, 2 × 60, or 3 × 40 MBq. The tumor volume was measured twice per week until the end of the experiment. The mean tumor volume for mice that received 2 × 15 = 30 and 1 × 30 MBq 177Lu-octreotate was reduced by 61% and 52%, respectively. The mean tumor volume was reduced by 91% and 44% for mice that received 2 × 30 = 60 and 1 × 60 MBq 177Lu-octreotate, respectively. After 120 MBq 177Lu-octreotate, given as 1–3 fractions, the mean tumor volume was reduced by 91–97%. Multiple fractions resulted in delayed regrowth and prolonged overall survival by 20–25% for the 120 MBq groups and by 45% for lower total activities, relative to one fraction. The results indicate that fractionation and hyperfractionation of 177Lu-octreotate are beneficial for tumor reduction and prolongs the time to regrowth.
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Affiliation(s)
- Mikael Elvborn
- Department of Medical Radiation Sciences, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, SE-413 45 Gothenburg, Sweden; (E.S.); (E.F.-A.)
- Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, SE-413 45 Gothenburg, Sweden
- Correspondence: ; Tel.: +46-(0)-31-342-95-99
| | - Emman Shubbar
- Department of Medical Radiation Sciences, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, SE-413 45 Gothenburg, Sweden; (E.S.); (E.F.-A.)
- Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, SE-413 45 Gothenburg, Sweden
| | - Eva Forssell-Aronsson
- Department of Medical Radiation Sciences, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, SE-413 45 Gothenburg, Sweden; (E.S.); (E.F.-A.)
- Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, SE-413 45 Gothenburg, Sweden
- Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, SE-413 45 Gothenburg, Sweden
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Cockburn KC, Toumi Z, Mackie A, Julyan P. Radioguided Surgery for Gastroenteropancreatic Neuroendocrine Tumours: a Systematic Literature Review. J Gastrointest Surg 2021; 25:3244-3257. [PMID: 34506015 PMCID: PMC8654712 DOI: 10.1007/s11605-021-05115-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 08/07/2021] [Indexed: 02/08/2023]
Abstract
BACKGROUND Radioguided surgery (RGS) for gastroenteropancreatic neuroendocrine tumours (GEP-NETs) has been suggested as a way to improve intraoperative lesion detection. This systematic literature review of reports of the use of RGS for GEP-NETs was performed to determine if there is a benefit. METHODS A literature search was conducted using Google Scholar and PubMed, and snowballing from any relevant literature. Full-text studies were included if they were published in the English language and reported outcomes of RGS on human subjects with GEP-NETs. Qualitative data synthesis was performed. RESULTS Twenty-six papers including a total of 209 patients were included. The tracers used were predominantly indium-111 pentetreotide, gallium-68 DOTA-peptides, and technetium-99m EDDA/HYNIC-peptides. Heterogeneous protocols make comparisons difficult, but most papers reported a benefit from the use of RGS in tumours in the gastrointestinal tract; utility in localisation of pancreatic tumours was less clear. Time between tracer administration and operation varied: from 16 h to 8 days with indium-111, 0-24 h with technetium-99m, and 19-193 min with gallium-68. Eight teams reported the thresholding technique used for discrimination-four used a ratio, four statistical methods, and one looked at the sensitivity and specificity of different cut-offs. Six teams performed follow-up of 24 patients (three pancreas, eight gastrinoma, 13 gastrointestinal tract) for between 3 months and 3 years. Two patients relapsed (one pancreas, one gastrinoma) between 6 and 12 months post-surgery. CONCLUSIONS RGS appears to aid in localisation of gastrointestinal NETs, but the benefit is more equivocal in pancreatic NETs. Further work into outcomes is warranted.
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Affiliation(s)
- Katrina Clair Cockburn
- Northern Medical Physics and Clinical Engineering, County Durham and Darlington NHS Foundation Trust, Hollyhurst Road, Darlington, DL3 6HX, UK.
| | - Zaher Toumi
- Department of General Surgery, County Durham and Darlington NHS Foundation Trust, Hollyhurst Road, Darlington, DL3 6HX, UK
| | - Alison Mackie
- Northern Medical Physics and Clinical Engineering, County Durham and Darlington NHS Foundation Trust, Hollyhurst Road, Darlington, DL3 6HX, UK
| | - Peter Julyan
- Department of Nuclear Medicine, The Christie Hospital NHS Foundation Trust, Manchester, UK
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Romiani A, Spetz J, Shubbar E, Lind DE, Hallberg B, Palmer RH, Forssell-Aronsson E. Neuroblastoma xenograft models demonstrate the therapeutic potential of 177Lu-octreotate. BMC Cancer 2021; 21:950. [PMID: 34433438 PMCID: PMC8386073 DOI: 10.1186/s12885-021-08551-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 06/14/2021] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Neuroblastoma (NB) is one of the most frequently diagnosed tumors in infants. NB is a neuroendocrine tumor type with various characteristics and features, and with diverse outcome. The most malignant NBs have a 5-year survival rate of only 40-50%, indicating the need for novel and improved treatment options. 177Lu-octreotate is routinely administered for treatment of neuroendocrine tumors overexpressing somatostatin receptors (SSTR). The aim of this study was to examine the biodistribution of 177Lu-octreotate in mice bearing aggressive human NB cell lines, in order to evaluate the potential usefulness of 177Lu-octreotate for treatment of NB. METHODS BALB/c nude mice bearing CLB-BAR, CLB-GE or IMR-32 tumor xenografts (n = 5-7/group) were i.v. injected with 0.15 MBq, 1.5 MBq or 15 MBq 177Lu-octreotate and sacrificed 1 h, 24 h, 48 h and 168 h after administration. The radioactivity concentration was determined for collected tissue samples, tumor-to-normal-tissue activity concentration ratios (T/N) and mean absorbed dose for each tissue were calculated. Immunohistochemical (IHC) staining for SSTR1-5, and Ki67 were carried out for tumor xenografts from the three cell lines. RESULTS High 177Lu concentration levels and T/N values were observed in all NB tumors, with the highest for CLB-GE tumor xenografts (72%IA/g 24 h p.i.; 1.5 MBq 177Lu-octreotate). The mean absorbed dose to the tumor was 6.8 Gy, 54 Gy and 29 Gy for CLB-BAR, CLB-GE and IMR-32, respectively, p.i. of 15 MBq 177Lu-octreotate. Receptor saturation was clearly observed in CLB-BAR, resulting in higher concentration levels in the tumor when lower activity levels where administered. IHC staining demonstrated highest expression of SSTR2 in CLB-GE, followed by CLB-BAR and IMR-32. CONCLUSION T/N values for all three human NB tumor xenograft types investigated were high relative to previously investigated neuroendocrine tumor types. The results indicate a clear potential of 177Lu-octreotate as a therapeutic alternative for metastatic NB.
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Affiliation(s)
- Arman Romiani
- Department of Medical Radiation Sciences, Institute of Clinical Sciences, Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
- Department of Medical Physics, Sahlgrenska University Hospital, SE-41345, Gothenburg, Sweden.
| | - Johan Spetz
- Department of Medical Radiation Sciences, Institute of Clinical Sciences, Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Emman Shubbar
- Department of Medical Radiation Sciences, Institute of Clinical Sciences, Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Dan E Lind
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Bengt Hallberg
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Ruth H Palmer
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Eva Forssell-Aronsson
- Department of Medical Radiation Sciences, Institute of Clinical Sciences, Sahlgrenska Center for Cancer Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg, Sweden
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Spetz J, Langen B, Rudqvist N, Parris TZ, Helou K, Nilsson O, Forssell-Aronsson E. Hedgehog inhibitor sonidegib potentiates 177Lu-octreotate therapy of GOT1 human small intestine neuroendocrine tumors in nude mice. BMC Cancer 2017; 17:528. [PMID: 28789624 PMCID: PMC5549301 DOI: 10.1186/s12885-017-3524-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 08/01/2017] [Indexed: 01/04/2023] Open
Abstract
Background 177Lu-octreotate can be used to treat somatostatin receptor expressing neuroendocrine tumors. It is highly effective in animal models, but clinical studies have so far only demonstrated low cure rates. Hedgehog inhibitors have shown therapeutic effect as monotherapy in neuroendocrine tumor model systems and might be one option to enhance the efficacy of 177Lu-octreotate therapy. The aim of this study was to determine the therapeutic effect of combination therapy using 177Lu-octreotate and the Hedgehog signaling pathway inhibitor sonidegib. Methods GOT1-bearing BALB/c nude mice were treated with either sonidegib (80 mg/kg twice a week via oral gavage), a single injection of 30 MBq 177Lu-octreotate i.v., or a combination of both. Untreated animals served as controls. Tumor size was measured twice-weekly using calipers. The animals were killed 41 d after injection followed by excision of the tumors. Total RNA was extracted from each tumor sample and then subjected to gene expression analysis. Gene expression patterns were compared with those of untreated controls using Nexus Expression 3.0, IPA and Gene Ontology terms. Western blot was carried out on total protein extracted from the tumor samples to analyze activation-states of the Hh and PI3K/AKT/mTOR pathways. Results Sonidegib monotherapy resulted in inhibition of tumor growth, while a significant reduction in mean tumor volume was observed after 177Lu-octreotate monotherapy and combination therapy. Time to progression was prolonged in the combination therapy group compared with 177Lu-octreotate monotherapy. Gene expression analysis revealed a more pronounced response following combination therapy compared with both monotherapies, regarding the number of regulated genes and biological processes. Several cancer-related signaling pathways (i.e. Wnt/β-catenin, PI3K/AKT/mTOR, G-protein coupled receptor, and Notch) were affected by the combination therapy, but not by either monotherapy. Protein expression analysis revealed an activation of the Hh- and PI3K/AKT/mTOR pathways in tumors exposed to 177Lu-octreotate monotherapy and combination therapy. Conclusions A comparative analysis of the different treatment groups showed that combination therapy using sonidegib and 177Lu-octreotate could be beneficial to patients with neuroendocrine tumors. Gene expression analysis revealed a functional interaction between sonidegib and 177Lu-octreotate, i.e. several cancer-related signaling pathways were modulated that were not affected by either monotherapy. Protein expression analysis indicated a possible PI3K/AKT/mTOR-dependent activation of the Hh pathway, independent of SMO. Electronic supplementary material The online version of this article (doi:10.1186/s12885-017-3524-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Johan Spetz
- Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Cancer Center, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, 413 45, Gothenburg, SE, Sweden.
| | - Britta Langen
- Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Cancer Center, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, 413 45, Gothenburg, SE, Sweden
| | - Nils Rudqvist
- Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Cancer Center, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, 413 45, Gothenburg, SE, Sweden
| | - Toshima Z Parris
- Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Cancer Center, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, 413 45, Gothenburg, SE, Sweden
| | - Khalil Helou
- Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Cancer Center, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, 413 45, Gothenburg, SE, Sweden
| | - Ola Nilsson
- Department of Pathology, Institute of Biomedicine, Sahlgrenska Cancer Center, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, 413 45, Gothenburg, SE, Sweden
| | - Eva Forssell-Aronsson
- Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Cancer Center, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, 413 45, Gothenburg, SE, Sweden
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Nicolas GP, Mansi R, McDougall L, Kaufmann J, Bouterfa H, Wild D, Fani M. Biodistribution, Pharmacokinetics, and Dosimetry of 177Lu-, 90Y-, and 111In-Labeled Somatostatin Receptor Antagonist OPS201 in Comparison to the Agonist 177Lu-DOTATATE: The Mass Effect. J Nucl Med 2017; 58:1435-1441. [DOI: 10.2967/jnumed.117.191684] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 04/11/2017] [Indexed: 01/08/2023] Open
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Dude I, Zhang Z, Rousseau J, Hundal-Jabal N, Colpo N, Merkens H, Lin KS, Bénard F. Evaluation of agonist and antagonist radioligands for somatostatin receptor imaging of breast cancer using positron emission tomography. EJNMMI Radiopharm Chem 2017; 2:4. [PMID: 29503845 PMCID: PMC5824694 DOI: 10.1186/s41181-017-0023-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Accepted: 03/28/2017] [Indexed: 01/21/2023] Open
Abstract
Background The somatostatin receptor subtype 2 (sstr2) is expressed on a majority of luminal breast cancers, however SPECT and scintigraphy imaging with agonistic sstr2 probes has been sub-optimal. High affinity antagonists can access more binding sites on the cell surface, resulting in higher tumor uptake and improved sensitivity. We compared the tumor uptake and biodistribution of the antagonist 68Ga-NODAGA-JR11 with two agonists 68Ga-DOTA-Tyr3-octreotide (68Ga-DOTATOC) and 68Ga-DOTA-Tyr3-octreotate (68Ga-DOTATATE), in the human, sstr2-positive, luminal breast cancer model: ZR-75-1. Results Peptides were assayed for binding affinity using a filtration-based competitive assay to sstr2. natGa-DOTATOC and natGa-DOTATATE had excellent affinity (inhibition constant Ki: 0.9 ± 0.1 nM and 1.4 ± 0.3 nM respectively) compared to natGa-NODAGA-JR11 (25.9 ± 0.2 nM). The number of binding sites on ZR-75-1 cells was determined in vitro by saturation assays. Agonist 67/natGa-DOTATOC bound to 6.64 ± 0.39 × 104 sites/cells, which was 1.5-fold higher than 67/natGa-NODAGA-JR11 and 2.3-fold higher than 67/natGa-DOTATATE. All three 68Ga-labeled peptides were obtained in good decay-corrected radiochemical yield (61-68%) and were purified by high performance liquid chromatography to ensure high specific activity (137 – 281 MBq/nmol at the end of synthesis). NOD scid gamma mice bearing ZR-75-1 tumors were injected intravenously with the labeled peptides and used for PET/CT imaging and biodistribution at 1 h post-injection. We found that 68Ga-DOTATOC had the highest tumor uptake (18.4 ± 2.9%ID/g), followed by 68Ga-DOTATATE (15.2 ± 2.2%ID/g) and 68Ga-NODAGA-JR11 (12.2 ± 0.8%ID/g). Tumor-to-blood and tumor-to-muscle ratios were also higher for the agonists (>40 and >150 respectively), compared to the antagonist (15.6 ± 2.2 and 45.2 ± 11.6 respectively). Conclusions The antagonist 68Ga-NODAGA-JR11 had the lowest tumor uptake and contrast compared to agonists 68Ga-DOTATOC and 68Ga-DOTATATE in ZR-75-1 xenografts. The main contributing factor to this result could be the use of an endogenously expressing cell line, which may differ from previously published transfected models in the number of low-affinity, antagonist-specific binding sites. The relative merit of agonists versus antagonists for sstr2 breast cancer imaging warrants further investigation, first in preclinical models with other sstr2-positive breast cancer xenografts, and ultimately in luminal breast cancer patients. Electronic supplementary material The online version of this article (doi:10.1186/s41181-017-0023-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Iulia Dude
- 1Department of Molecular Oncology, BC Cancer Agency Research Centre, 675 West 10th Ave, Vancouver, V5Z 1 L3 BC Canada
| | - Zhengxing Zhang
- 1Department of Molecular Oncology, BC Cancer Agency Research Centre, 675 West 10th Ave, Vancouver, V5Z 1 L3 BC Canada
| | - Julie Rousseau
- 1Department of Molecular Oncology, BC Cancer Agency Research Centre, 675 West 10th Ave, Vancouver, V5Z 1 L3 BC Canada
| | - Navjit Hundal-Jabal
- 1Department of Molecular Oncology, BC Cancer Agency Research Centre, 675 West 10th Ave, Vancouver, V5Z 1 L3 BC Canada
| | - Nadine Colpo
- 1Department of Molecular Oncology, BC Cancer Agency Research Centre, 675 West 10th Ave, Vancouver, V5Z 1 L3 BC Canada
| | - Helen Merkens
- 1Department of Molecular Oncology, BC Cancer Agency Research Centre, 675 West 10th Ave, Vancouver, V5Z 1 L3 BC Canada
| | - Kuo-Shyan Lin
- 1Department of Molecular Oncology, BC Cancer Agency Research Centre, 675 West 10th Ave, Vancouver, V5Z 1 L3 BC Canada.,2Department of Radiology, University of British Columbia, Vancouver, BC Canada
| | - François Bénard
- 1Department of Molecular Oncology, BC Cancer Agency Research Centre, 675 West 10th Ave, Vancouver, V5Z 1 L3 BC Canada.,2Department of Radiology, University of British Columbia, Vancouver, BC Canada
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Notni J, Steiger K, Hoffmann F, Reich D, Schwaiger M, Kessler H, Wester HJ. Variation of Specific Activities of 68Ga-Aquibeprin and 68Ga-Avebetrin Enables Selective PET Imaging of Different Expression Levels of Integrins α5β1 and αvβ3. J Nucl Med 2016; 57:1618-1624. [DOI: 10.2967/jnumed.116.173948] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 03/29/2016] [Indexed: 12/22/2022] Open
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Schüler E, Österlund A, Forssell-Aronsson E. The amount of injected 177Lu-octreotate strongly influences biodistribution and dosimetry in C57BL/6N mice. Acta Oncol 2015; 55:68-76. [PMID: 25813472 DOI: 10.3109/0284186x.2015.1027001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND (177)Lu-octreotate therapy has proven to give favorable results after treatment of patients with neuroendocrine tumors. Much focus has been on the binding and uptake of (177)Lu-octreotate in tumor tissue, but biodistribution properties in normal tissues is still not fully understood, and the effect of receptor saturation may be important. The aim of this study was to investigate the influence of the amount of (177)Lu-octreotate on the biodistribution of (177)Lu-octreotate in normal tissues in mice. MATERIAL AND METHODS C57BL/6N female mice were intravenously injected with 0.1-150 MBq (177)Lu-octreotate (0.039 μg peptide/MBq). The mice were killed 0.25 h to 14 days after injection by cardiac puncture under anesthesia. Activity concentration was determined in blood, bone marrow, kidneys, liver, lungs, pancreas, and spleen, and mean absorbed doses were calculated. RESULTS The activity concentration varied with time and amount of injected activity. At 4-8 h after injection, a local maximum in activity concentration was found for liver, lungs, pancreas, and spleen. With the exception for the lower injected activities (0.1-1 MBq), the overall highest uptake was found in the kidneys (%IA/g). Large variations were found and the activity concentration in kidneys was 11-23%IA/g at 4 h, and 0.22-1.9%IA/g at 7 days after injection. Furthermore, a clear reduction in activity concentration with increased injected activity was observed for lungs, pancreas and spleen. CONCLUSION The activity concentration in all tissues investigated was strongly influenced by the amount of (177)Lu-octreotate injected. Large differences in mean absorbed dose per unit injected activity were found between low (0.1-1 MBq, 0.0039-0.039 μg) and moderate amounts (5-45 MBq, 0.2-1.8 μg). Furthermore, the results clearly showed the need for better ways to estimate absorbed dose to bone marrow other than methods based on a single blood sample analysis. Since the absorbed dose to critical organs will limit the amount of (177)Lu-octreotate administered, these findings must be taken into consideration when optimizing this type of therapy.
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Affiliation(s)
- Emil Schüler
- Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Cancer Center, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Andreas Österlund
- Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Cancer Center, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Eva Forssell-Aronsson
- Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Cancer Center, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
- Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg, Sweden
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Konijnenberg MW, Breeman WAP, de Blois E, Chan HS, Boerman OC, Laverman P, Kolenc-Peitl P, Melis M, de Jong M. Therapeutic application of CCK2R-targeting PP-F11: influence of particle range, activity and peptide amount. EJNMMI Res 2014; 4:47. [PMID: 26116111 PMCID: PMC4452684 DOI: 10.1186/s13550-014-0047-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 08/15/2014] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Targeted radionuclide therapy with high-energy beta-emitters is generally considered suboptimal to cure small tumours (<300 mg). Tumour targeting of the CCK2 receptor-binding minigastrin analogue PP-F11 was determined in a tumour-bearing mouse model at increasing peptide amounts. The optimal therapy was analysed for PP-F11 labelled with (90)Y, (177)Lu or (213)Bi, accounting for the radionuclide specific activities (SAs), the tumour absorbed doses and tumour (radio) biology. METHODS Tumour uptake of (111)In-PP-F11 was determined in nude mice bearing CCK2 receptor-transfected A431 xenografts at 1 and 4 h post-injection for escalating peptide masses of 0.03 to 15 nmol/mouse. The absorbed tumour dose was estimated, assuming comparable biodistributions of the (90)Y, (177)Lu or (213)Bi radiolabelled peptides. The linear-quadratic (LQ) model was used to calculate the tumour control probabilities (TCP) as a function of tumour mass and growth. RESULTS Practically achievable maximum SAs for PP-F11 labelled with (90)Y and (177)Lu were 400 MBq (90)Y/nmol and 120 MBq(177)Lu/nmol. Both the large elution volume from the 220 MBq (225)Ac generator used and reaction kinetics diminished the maximum achieved (213)Bi SA in practice: 40 MBq (213)Bi/nmol. Tumour uptakes decreased rapidly with increasing peptide amounts, following a logarithmic curve with ED50 = 0.5 nmol. At 0.03 nmol peptide, the (300 mg) tumour dose was 9 Gy after 12 MBq (90)Y-PP-F11, and for (111)In and (177)Lu, this was 1 Gy. A curative dose of 60 Gy could be achieved with a single administration of 111 MBq (90)Y labelled to 0.28 nmol PP-F11 or with 4 × 17 MBq (213)Bi (0.41 nmol) when its α-radiation relative biological effectiveness (RBE) was assumed to be 3.4. Repeated dosing is preferable to avoid complete tumour receptor saturation. Tumours larger than 200 mg are curable with (90)Y-PP-F11; the other radionuclides perform better in smaller tumours. Furthermore, (177)Lu is not optimal for curing fast-growing tumours. CONCLUSIONS Receptor saturation, specific radiopharmaceutical activities and absorbed doses in the tumour together favour therapy with the CCK2 receptor-binding peptide PP-F11 labelled with (90)Y, despite its longer β-particle range in tissue, certainly for tumours larger than 300 mg. The predicted TCPs are of theoretical nature and need to be compared with the outcome of targeted radionuclide experiments.
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Affiliation(s)
- Mark W Konijnenberg
- Department of Nuclear Medicine, Erasmus MC, PO Box 2040, 3000, CA, Rotterdam, The Netherlands,
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11
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Vandeghinste B, Van Holen R, Vanhove C, De Vos F, Vandenberghe S, Staelens S. Use of a Ray-Based Reconstruction Algorithm to Accurately Quantify Preclinical MicroSPECT Images. Mol Imaging 2014. [DOI: 10.2310/7290.2014.00007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Bert Vandeghinste
- From the Department of Electronics and Information Systems, Medical Image and Signal Processing (MEDISIP) Research Group, Ghent University-IBBT-IBiTech, Ghent, Belgium; Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium; and Molecular Imaging Center Antwerp (MICA), University of Antwerp, Wilrijk, Belgium
| | - Roel Van Holen
- From the Department of Electronics and Information Systems, Medical Image and Signal Processing (MEDISIP) Research Group, Ghent University-IBBT-IBiTech, Ghent, Belgium; Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium; and Molecular Imaging Center Antwerp (MICA), University of Antwerp, Wilrijk, Belgium
| | - Christian Vanhove
- From the Department of Electronics and Information Systems, Medical Image and Signal Processing (MEDISIP) Research Group, Ghent University-IBBT-IBiTech, Ghent, Belgium; Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium; and Molecular Imaging Center Antwerp (MICA), University of Antwerp, Wilrijk, Belgium
| | - Filip De Vos
- From the Department of Electronics and Information Systems, Medical Image and Signal Processing (MEDISIP) Research Group, Ghent University-IBBT-IBiTech, Ghent, Belgium; Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium; and Molecular Imaging Center Antwerp (MICA), University of Antwerp, Wilrijk, Belgium
| | - Stefaan Vandenberghe
- From the Department of Electronics and Information Systems, Medical Image and Signal Processing (MEDISIP) Research Group, Ghent University-IBBT-IBiTech, Ghent, Belgium; Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium; and Molecular Imaging Center Antwerp (MICA), University of Antwerp, Wilrijk, Belgium
| | - Steven Staelens
- From the Department of Electronics and Information Systems, Medical Image and Signal Processing (MEDISIP) Research Group, Ghent University-IBBT-IBiTech, Ghent, Belgium; Laboratory of Radiopharmacy, Ghent University, Ghent, Belgium; and Molecular Imaging Center Antwerp (MICA), University of Antwerp, Wilrijk, Belgium
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Forssell-Aronsson E, Spetz J, Ahlman H. Radionuclide therapy via SSTR: future aspects from experimental animal studies. Neuroendocrinology 2013; 97:86-98. [PMID: 22572526 DOI: 10.1159/000336086] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Accepted: 12/11/2011] [Indexed: 12/24/2022]
Abstract
There is need for better therapeutic options for neuroendocrine tumours. The aim of this review was to summarize results of experimental animal studies and raise ideas for future radionuclide therapy based on high expression of somatostatin (SS) receptors by many neuroendocrine tumours. In summary, one of the major options is individualized treatment for each patient, including choice of SS analogues, radionuclides and treatment schedules. Other options are methods to increase the treatment effect on tumour tissue (increasing tumour uptake and retention by upregulation of receptor expression and avoiding saturation of receptor binding), methods to increase the tumour tissue response (by choice of radionuclides, SS analogues or combined therapies), and methods to reduce side effects (diminished uptake and retention in critical organs and reduced normal tissue response). Furthermore, combination therapy with other radiopharmaceuticals, cytotoxic drugs or radiosensitizers can be considered to enhance the effects of radiolabelled SS analogues.
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Affiliation(s)
- Eva Forssell-Aronsson
- Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Cancer Centre, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
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Tolmachev V, Wållberg H, Sandström M, Hansson M, Wennborg A, Orlova A. Optimal specific radioactivity of anti-HER2 Affibody molecules enables discrimination between xenografts with high and low HER2 expression levels. Eur J Nucl Med Mol Imaging 2010; 38:531-9. [PMID: 21069318 DOI: 10.1007/s00259-010-1646-3] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Accepted: 10/04/2010] [Indexed: 12/13/2022]
Abstract
PURPOSE Overexpression of the HER2 receptor is a biomarker for predicting those patients who may benefit from trastuzumab therapy. Radiolabelled Affibody molecules can be used to visualize HER2 expression in tumour xenografts with high sensitivity. However, previous studies demonstrated that the difference in uptake in xenografts with high and low HER2 expression levels is not proportional to the difference in expression levels. We hypothesized that discrimination between tumours with high and low HER2 expression may be improved by increasing the injected dose (reducing the specific activity) of the tracer. METHODS The influence of injected dose of anti-HER2 (111)In-DOTA-Z(HER2 342) Affibody molecule on uptake in SKOV-3 (high HER2 expression) and LS174T (low expression) xenografts was investigated. The optimal range of injected doses enabling discrimination between xenografts with high and low expression was determined. To verify this, tumour uptake was measured in mice carrying both SKOV-3 and LS174T xenografts after injection of either 1 or 15 μg (111)In-DOTA-Z(HER2:342). RESULTS An increase in the injected dose caused a linear decrease in the radioactivity accumulation in the LS174T xenografts (low HER2 expression). For SKOV-3 xenografts, the dependence of the tumour uptake on the injected dose was less dramatic. The injection of 10-30 μg (111)In-DOTA-Z(HER2:342) per mouse led to the largest difference in uptake between the two types of tumour. Experiments in mice bearing two xenografts confirmed that the optimized injected dose enabled better discrimination of expression levels. CONCLUSION Careful optimization of the injected dose of Affibody molecules is required for maximum discrimination between xenografts with high and low levels of HER2 expression. This information has potential relevance for clinical imaging applications.
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Affiliation(s)
- Vladimir Tolmachev
- Biomedical Radiation Sciences, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden.
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In vivo binding of [68Ga]-DOTATOC to somatostatin receptors in neuroendocrine tumours — impact of peptide mass. Nucl Med Biol 2010; 37:265-75. [DOI: 10.1016/j.nucmedbio.2009.11.008] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Revised: 10/28/2009] [Accepted: 11/25/2009] [Indexed: 11/20/2022]
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15
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Kareem H, Sandström K, Elia R, Gedda L, Anniko M, Lundqvist H, Nestor M. Blocking EGFR in the liver improves the tumor-to-liver uptake ratio of radiolabeled EGF. Tumour Biol 2010; 31:79-87. [DOI: 10.1007/s13277-009-0011-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Accepted: 12/21/2009] [Indexed: 01/19/2023] Open
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Velikyan I, Beyer GJ, Bergström-Pettermann E, Johansen P, Bergström M, Långström B. The importance of high specific radioactivity in the performance of 68Ga-labeled peptide. Nucl Med Biol 2008; 35:529-36. [DOI: 10.1016/j.nucmedbio.2008.03.002] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2007] [Revised: 02/14/2008] [Accepted: 03/04/2008] [Indexed: 10/21/2022]
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17
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Melis M, Krenning EP, Bernard BF, de Visser M, Rolleman E, de Jong M. Renal uptake and retention of radiolabeled somatostatin, bombesin, neurotensin, minigastrin and CCK analogues: species and gender differences. Nucl Med Biol 2007; 34:633-41. [PMID: 17707803 DOI: 10.1016/j.nucmedbio.2007.05.002] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2007] [Revised: 04/24/2007] [Accepted: 05/08/2007] [Indexed: 02/04/2023]
Abstract
INTRODUCTION During therapy with radiolabeled peptides, the kidney is most often the critical organ. Newly developed peptides are evaluated preclinically in different animal models before their application in humans. In this study, the renal retention of several radiolabeled peptides was compared in male and female rats and mice. METHODS After intravenous injection of radiolabeled peptides [somatostatin, cholecystokinin (CCK), minigastrin, bombesin and neurotensin analogues], renal uptake was determined in both male and female Lewis rats and C57Bl mice. In addition, ex vivo autoradiography of renal sections was performed to localize accumulated radioactivity. RESULTS An equal distribution pattern of renal radioactivity was found for all peptides: high accumulation in the cortex, lower accumulation in the outer medulla and no radioactivity in the inner medulla of the kidneys. In both male rats and mice, an increasing renal uptake was found: [(111)In-DTPA]CCK8<[(111)In-DTPA-Pro(1),Tyr(4)]bombesin approximately [(111)In-DTPA]neurotensin<[(111)In-DTPA]octreotide<<[(111)In-DTPA]MG0. Renal uptake of [(111)In-DTPA]octreotide in rats showed no gender difference, and renal radioactivity was about constant over time. In mice, however, renal uptake in females was significantly higher than that in males and decreased rapidly over time in both genders. Moreover, renal radioactivity in female mice injected with [(111)In-DTPA]octreotide showed a different localization pattern. CONCLUSIONS Regarding the renal uptake of different radiolabeled peptides, both species showed the same ranking order. Similar to findings in patients, rats showed comparable and constant renal retention of radioactivity in both genders, in contrast to mice. Therefore, rats appear to be the more favorable species for the study of the renal retention of radioactivity.
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Affiliation(s)
- Marleen Melis
- Department of Nuclear Medicine, Erasmus MC Rotterdam, 3015 CE Rotterdam, The Netherlands.
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Schmitt A, Bernhardt P, Nilsson O, Ahlman H, Kölby L, Forssell-Aronsson E. Differences in biodistribution between 99mTc-depreotide, 111In-DTPA-octreotide, and 177Lu-DOTA-Tyr3-octreotate in a small cell lung cancer animal model. Cancer Biother Radiopharm 2005; 20:231-6. [PMID: 15869461 DOI: 10.1089/cbr.2005.20.231] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
AIM (177)Lu-DOTA-Tyr(3)-octreotate is a candidate radiopharmaceutical for the therapy of somatostatin receptor (sstr)-positive small cell lung cancer (SCLC). Scintigraphy of lung tumors is made with 2 alternative somatostatin analogs, (111)In-DTPA-octreotide or (99m)Tc-depreotide. The aim of this study was to compare the biodistribution of these 3 radiopharmaceuticals in SCLC xenografted to nude mice. METHODS Nude mice, bearing tumors from the human SCLC cell line NCI-H69, were intravenously injected with 10 MBq (2.4 microg) (99m)Tc-depreotide and 2 MBq (0.5 microg) (111)In-DTPA-octreotide simultaneously. The activity concentration (%IA/g) was measured in tumor and normal tissue at 2, 4, and 24 hours postinjection (hpi). The results were compared with earlier published biodistribution data of 3 MBq (0.7 microg) (177)Lu-DOTA-Tyr(3)-octreotate in the same animal model. RESULTS The activity concentration of (111)In-DTPAoctreotide in tumor was higher than the activity concentration of (99m)Tc-depreotide at 2-24 hpi, p < 0.05. The highest tumor uptake at 24 hpi was, however, found for (177)Lu-DOTA-Tyr(3)-octreotate. The activity concentration of (99m)Tc-depreotide was significantly higher in the heart, lungs, liver, the salivary glands, spleen, and bone marrow than for (111)In-DTPA-octreotide at 2-24 hpi. Saturation of the somatostatin receptors may have influenced the uptake in tumor and sstr-positive normal tissues. CONCLUSION The low tumor-to-lung and tumor-to-liver activity concentration ratios for (99m)Tc-depreotide could result in a lower detection rate of SCLC with this compound versus (111)In-DTPA-octreotide. (177)Lu-DOTA-Tyr(3)-octreotate gave the highest tumor-activity concentration, and has, thus, the best properties for therapy.
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Affiliation(s)
- Anneli Schmitt
- Department of Radiation Physics, Göteborg University, Sahlgrenska University Hospital, SE-413 45 Göteborg, Sweden.
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Eberle AN, Mild G, Froidevaux S. Receptor-Mediated Tumor Targeting with Radiopeptides. Part 1. General Concepts and Methods: Applications to Somatostatin Receptor-Expressing Tumors. J Recept Signal Transduct Res 2004; 24:319-455. [PMID: 15648449 DOI: 10.1081/rrs-200040939] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Radiolabeled peptides have become important tools in nuclear oncology, both as diagnostics and more recently also as therapeutics. They represent a distinct sector of the molecular targeting approach, which in many areas of therapy will implement the old "magic bullet" concept by specifically directing the therapeutic agent to the site of action. In this three-part review, we present a comprehensive overview of the literature on receptor-mediated tumor targeting with the different radiopeptides currently studied. Part I summarizes the general concepts and methods of targeting, the selection of radioisotopes, chelators, and the criteria of peptide ligand development. Then, the >400 studies on the application to somatostatin/somatostatin-release inhibiting factor receptor-mediated tumor localization and treatment will be reviewed, demonstrating that peptide radiopharmaceuticals have gained an important position in clinical medicine.
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Affiliation(s)
- Alex N Eberle
- Laboratory of Endocrinology, Department of Research, University Hospital and University Children's Hospital, Basel, Switzerland.
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Nilsson O, Kölby L, Bernhardt P, Forssell-Aronsson E, Johanson V, Ahlman H. GOT1 xenografted to nude mice: a unique model for in vivo studies on SSTR-mediated radiation therapy of carcinoid tumors. Ann N Y Acad Sci 2004; 1014:275-9. [PMID: 15153445 DOI: 10.1196/annals.1294.031] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Malignant carcinoid tumors express high numbers of somatostatin receptors. Radiation therapy using labeled somatostatin analogs is a novel treatment modality for these tumors. We have analyzed the biokinetics and therapeutic effect of radiolabeled somatostatin analog on a human midgut carcinoid grafted to nude mice. A transplantable human midgut carcinoid (GOT1) was grafted to the back of nude mice. Tumor-bearing mice were injected with (111)In-DTPA-D-Phe(1)-octreotide, followed by measurement of (111)In activity concentration ratios in tumor tissues. Tumor-bearing mice were also injected with (177)Lu-DOTA-Tyr(3)-octreotate and followed for 7 days. The concentration of (111)In-DTPA-D-Phe(1)-octreotide in tumor tissues was very high 4 hours postinjection with 0.4-13% of injected activity per gram. Injection of 30-120 MBq (177)Lu-DOTA-Tyr(3)-octreotate reduced tumor volume to 7-14% of the original tumor volume 7 days postinjection. Microscopic analysis of treated tumors revealed widespread areas of tumor cell necrosis and fibrosis. It was found that grafted GOT1 cells to nude mice represent an authentic model for studying human midgut carcinoids. Radiolabeled somatostatin analogs have a high selectivity for tumor tissue and can induce tumor cell necrosis. Radiotherapy of carcinoid tumors with (177)Lu-DOTA-Tyr(3)-octreotate appears to be a promising treatment modality for either palliative treatment or completion therapy after attempted surgical cure.
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Affiliation(s)
- Ola Nilsson
- Lundberg Laboratory for Cancer Research at the Department of Pathology, Sahlgrenska University Hospital, Göteborg, Sweden.
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