scholarly journals Combination of terbium-161 with somatostatin receptor antagonists—a potential paradigm shift for the treatment of neuroendocrine neoplasms

Author(s):  
Francesca Borgna ◽  
Stephanie Haller ◽  
Josep M. Monné Rodriguez ◽  
Mihaela Ginj ◽  
Pascal V. Grundler ◽  
...  

Abstract Purpose The β¯-emitting terbium-161 also emits conversion and Auger electrons, which are believed to be effective in killing single cancer cells. Terbium-161 was applied with somatostatin receptor (SSTR) agonists that localize in the cytoplasm (DOTATOC) and cellular nucleus (DOTATOC-NLS) or with a SSTR antagonist that localizes at the cell membrane (DOTA-LM3). The aim was to identify the most favorable peptide/terbium-161 combination for the treatment of neuroendocrine neoplasms (NENs). Methods The capability of the 161Tb- and 177Lu-labeled somatostatin (SST) analogues to reduce viability and survival of SSTR-positive AR42J tumor cells was investigated in vitro. The radiopeptides’ tissue distribution profiles were assessed in tumor-bearing mice. The efficacy of terbium-161 compared to lutetium-177 was investigated in therapy studies in mice using DOTATOC or DOTA-LM3, respectively. Results In vitro, [161Tb]Tb-DOTA-LM3 was 102-fold more potent than [177Lu]Lu-DOTA-LM3; however, 161Tb-labeled DOTATOC and DOTATOC-NLS were only 4- to fivefold more effective inhibiting tumor cell viability than their 177Lu-labeled counterparts. This result was confirmed in vivo and demonstrated that [161Tb]Tb-DOTA-LM3 was significantly more effective in delaying tumor growth than [177Lu]Lu-DOTA-LM3, thereby, prolonging survival of the mice. A therapeutic advantage of terbium-161 over lutetium-177 was also manifest when applied with DOTATOC. Since the nuclear localizing sequence (NLS) compromised the in vivo tissue distribution of DOTATOC-NLS, it was not used for therapy. Conclusion The use of membrane-localizing DOTA-LM3 was beneficial and profited from the short-ranged electrons emitted by terbium-161. Based on these preclinical data, [161Tb]Tb-DOTA-LM3 may outperform the clinically employed [177Lu]Lu-DOTATOC for the treatment of patients with NENs.

2014 ◽  
Author(s):  
Raul M Luque ◽  
Mario Duran-Prado ◽  
David Rincon-Fernandez ◽  
Marta Hergueta-Redondo ◽  
Michael D Culler ◽  
...  

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii102-ii103
Author(s):  
Syed Faaiz Enam ◽  
Jianxi Huang ◽  
Cem Kilic ◽  
Connor Tribble ◽  
Martha Betancur ◽  
...  

Abstract As a cancer therapy, hypothermia has been used at sub-zero temperatures to cryosurgically ablate tumors. However, these temperatures can indiscriminately damage both tumorous and healthy cells. Additionally, strategies designed to kill tumor typically accelerate their evolution and recurrence can be inevitable in cancers such as glioblastoma (GBM). To bypass these limitations, here we studied the use of hypothermia as a cytostatic tool against cancer and deployed it against an aggressive rodent model of GBM. To identify the minimal dosage of ‘cytostatic hypothermia’, we cultured at least 4 GBM lines at 4 continuous or intermittent degrees of hypothermia and evaluated their growth rates through a custom imaging-based assay. This revealed cell-specific sensitivities to hypothermia. Subsequently, we examined the effects of cytostatic hypothermia on these cells by a cursory study of their cell-cycle, energy metabolism, and protein synthesis. Next, we investigated the use of cytostatic hypothermia as an adjuvant to chemotherapy and CAR T immunotherapy. Our studies demonstrated that cytostatic hypothermia did not interfere with Temozolomide in vitro and may have been synergistic against at least 1 GBM line. Interestingly, we also demonstrated that CAR T immunotherapy can function under cytostatic hypothermia. To assess the efficacy of hypothermia in vivo, we report the design of an implantable device to focally administer cytostatic hypothermia in an aggressive rodent model of F98 GBM. Cytostatic hypothermia significantly doubled the median survival of tumor-bearing rats with no obvious signs of distress. The absence of gross behavioral alterations is in concurrence with literature suggesting the brain is naturally resilient to focal hypothermia. Based on these findings, we anticipate that focally administered cytostatic hypothermia alone has the potential to delay tumor recurrence or increase progression-free survival in patients. Additionally, it could also provide more time to evaluate concomitant, curative cytotoxic treatments.


2020 ◽  
Vol 14 (1) ◽  
pp. 19
Author(s):  
Melpomeni Fani ◽  
Viktoria Weingaertner ◽  
Petra Kolenc Peitl ◽  
Rosalba Mansi ◽  
Raghuvir H. Gaonkar ◽  
...  

Recently, radiolabelled antagonists targeting somatostatin receptors subtype 2 (SST2) in neuroendocrine neoplasms demonstrated certain superior properties over agonists. Within the ERA-PerMED project “TECANT” two 99mTc-Tetramine (N4)-derivatized SST2 antagonists (TECANT-1 and TECANT-2) were studied for the selection of the best candidate for clinical translation. Receptor-affinity, internalization and dissociation studies were performed in human embryonic kidney-293 (HEK293) cells transfected with the human SST2 (HEK-SST2). Log D, protein binding and stability in human serum were assessed. Biodistribution and SPECT/CT studies were carried out in nude mice bearing HEK-SST2 xenografts, together with dosimetric estimations from mouse-to-man. [99mTc]Tc-TECANT-1 showed higher hydrophilicity and lower protein binding than [99mTc]-TECANT-2, while stability was comparable. Both radiotracers revealed similar binding affinity, while [99mTc]Tc-TECANT-1 had higher cellular uptake (>50%, at 2 h/37 °C) and lower dissociation rate (<30%, at 2 h/37 °C). In vivo, [99mTc]Tc-TECANT-1 showed lower blood values, kidney and muscles uptake, whereas tumour uptake was comparable to [99mTc]Tc-TECANT-2. SPECT/CT imaging confirmed the biodistribution results, providing the best tumour-to-background image contrast for [99mTc]Tc-TECANT-1 at 4 h post-injection (p.i.). The estimated radiation dose amounted to approximately 6 µSv/MBq for both radiotracers. This preclinical study provided the basis of selection of [99mTc]Tc-TECANT-1 for clinical translation of the first 99mTc-based SST2 antagonist.


Molecules ◽  
2018 ◽  
Vol 23 (11) ◽  
pp. 2883 ◽  
Author(s):  
Cang Zhang ◽  
Xiaolan Zhang ◽  
Guangji Wang ◽  
Ying Peng ◽  
Xueyuan Zhang ◽  
...  

C118P, a phosphate prodrug of C118, which is a novel microtubule protein inhibitor, is currently under Phase I clinical development in China for treating ovarian cancer and lung cancer. The preclinical pharmacokinetics of prodrug C118P and its metabolite C118 were extensively characterized in vivo in mice, rats, and dogs and in vitro to support the further development of C118P. The preclinical tissue distribution and excretion were investigated in rats. Plasma protein binding in mice, rat, and human, and hepatic microsomal metabolic stability in mice, rat, dog, monkey, and human, were also evaluated. The (AUC0-inf) and C30s of C118P at 50 mg/kg in rats and 6 mg/kg in dogs, and the C2min of C118 at 6 mg/kg in dogs increased less than the dosage increase, suggested nonlinear pharmacokinetic occurred at high dose. As a prodrug, C118P can be quickly hydrolyzed into C118 after an intravenous administration. The unbound C118 in plasma is slightly higher than C118P. C118P can hardly penetrate the tissue, while C118 can distribute widely into tissues. In tumor-bearing nude mice, the concentration of C118 is high in lung, ovary, and tumor, with an extended half-life in tumor. C118P is a promising candidate prodrug for further clinical development.


2018 ◽  
Vol 30 (23) ◽  
pp. 8587-8596 ◽  
Author(s):  
Alexandra Van Driessche ◽  
Agnese Kocere ◽  
Hannelien Everaert ◽  
Lutz Nuhn ◽  
Simon Van Herck ◽  
...  

2022 ◽  
Vol 12 ◽  
Author(s):  
Leanne De Silva ◽  
Ju-Yen Fu ◽  
Thet Thet Htar ◽  
Wan Hamirul Bahrin Wan Kamal ◽  
Azahari Kasbollah ◽  
...  

The purpose of this work was to study the biodistribution of niosomes in tumor-implanted BALB/c mice using gamma scintigraphy. Niosomes were first formulated and characterized, then radiolabeled with Technetium-99 m (99mTc). The biodistribution of 99mTc-labeled niosomes was evaluated in tumor-bearing mice through intravenous injection and imaged with gamma scintigraphy. The labeled complexes possessed high radiolabeling efficiency (98.08%) and were stable in vitro (&gt;80% after 8 h). Scintigraphic imaging showed negligible accumulation in the stomach and thyroid, indicating minimal leaching of the radiolabel in vivo. Radioactivity was found mainly in the liver, spleen and kidneys. Tumor-to-muscle ratio indicated a higher specificity of the formulation for the tumor area. Overall, the formulated niosomes are stable both in vitro and in vivo, and show preferential tumor accumulation.


2021 ◽  
Author(s):  
Yinghui Song ◽  
Zhihua Zhang ◽  
Qin Chai ◽  
GuoYi Xia ◽  
Zhangtao Yu ◽  
...  

Abstract Intrahepatic cholangiocarcinoma (ICC) is a rare high-fatal hepatobiliary malignancy, the treatment option of ICC is very limited, and the prognosis is also poor. Recently, emerging evidence has shown the potential of quercetin (QE) for cancer therapy. We explored the effect and mechanism of QE on ICC in vitro and in vivo. CCK-8 assay and Clonogenic assay showed that QE could inhibit ICC cells proliferation and survival. PI staining suggested QE could induce ICC cells arrest in G1 phase. AV/PI staining suggested QE could promote ICC cells apoptosis. Wound Healing Assay and Transwell chamber experiment suggested QE could inhibit ICC cells EMT. RNA-seq, the changes in the structure of mitochondria by electron microscopy and the key markers of ferroptosis (free iron ions, MDA, SOD, GPX4) were supported QE could promote ferroptosis in ICC cells. Molecular docking showed that QE had direct interaction with NF-κB and GPX4. In vivo, treatment with QE inhibited tumor growth and prolonged survival time of tumor-bearing nude mice. Our data for the first time suggest that QE is a new ferroptosis inducer and combinative treatment of inhibiting NF-κB in ICC cells by inducing ferroptosis and inhibiting EMT, which will hopefully provide a prospective strategy for ICC patients.


2020 ◽  
Author(s):  
Sheng Zhao ◽  
Wen-Bin Pan ◽  
Hui-Jie Jiang ◽  
Rong-Jun Zhang ◽  
Hao Jiang ◽  
...  

Abstract Background : Preclinical and clinical studies have demonstrated that immunotherapy has effectively delayed tumor progression, and the clinical outcomes of anti-PD-1/PD-L1 therapy were related to PD-L1 expression level in the tumors. A 131 I-labeled anti-PD-L1 monoclonal antibody tracer, 131 I-PD-L1-Mab, was developed to study the target ability of non-invasive Cerenkov luminescence imaging in colorectal cancer xenograft mice.Method: Anti-PD-L1 monoclonal antibody labeled with 131 I( 131 I-PD-L1-Mab), and in vitro binding assays were used to evaluate the affinity of 131 I-PD-L1-Mab to PD-L1 and their binding level to different colorectal cancer cells, and compared with flow cytometry, western blot analysis, and immunofluorescence staining. The clinical application value of 131 I-PD-L1-Mab was evaluated through biodistribution and Cerenkov luminescence imaging, and different tumor-bearing models expressing PD-L1 were evaluated.Results: 131 I-PD-L1-Mab showed high affinity to PD-L1, and the equilibrium dissociation constant was 1.069×10 -9 M. The competitive inhibition assay further confirmed the specific binding ability of 131 I-PD-L1-Mab. In four different tumor-bearing models with different PD-L1 expression, the biodistribution and Cerenkov luminescence imaging showed that the RKO tumors demonstrated the highest uptake of the tracer 131 I-PD-L1-Mab, with a maximum uptake of 1.613 ± 0.738% ID/g at 120 h.Conclusions: There is a great potential for 131 I-PD-L1-Mab noninvasive Cerenkov luminescence imaging to assess the status of tumor PD-L1 expression and select patients for anti-PD-L1 targeted therapy.


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