The Experts below are selected from a list of 507 Experts worldwide ranked by ideXlab platform
Raymond M Reilly - One of the best experts on this subject based on the ideXlab platform.
-
effectiveness and normal tissue toxicity of auger electron ae radioimmunotherapy rit with 111in in bn dtpa Nimotuzumab in mice with triple negative or trastuzumab resistant human breast cancer xenografts that overexpress egfr
Nuclear Medicine and Biology, 2020Co-Authors: Conrad Chan, Humphrey Fonge, Karen Lam, Raymond M ReillyAbstract:Abstract Introduction Our objective was to evaluate the effectiveness and normal tissue toxicity of Nimotuzumab labeled with the Auger electron (AE)-emitter, 111In ([111In]In-Bn-DTPA-Nimotuzumab) for radioimmunotherapy (RIT) of human triple-negative breast cancer (TNBC) or trastuzumab-resistant HER2-positive BC tumors overexpressing epidermal growth factor receptors (EGFR) in athymic mice. Methods Normal tissue toxicity was studied in non-tumor-bearing Balb/c mice i.v. administered 9.0 or 28.6 MBq (3 mg/kg) of [111In]In-Bn-DTPA-Nimotuzumab, unlabeled Nimotuzumab (3 mg/kg) or normal saline. A complete blood cell count (CBC) and serum alanine aminotransferase (ALT) and creatinine (Cr) were measured at 14 days. Body weight was monitored. RIT studies were performed in CD-1 athymic mice engrafted s.c. with MDA-MB-468 human TNBC tumors or TrR1 HER2-positive but trastuzumab-resistant BC tumors. Mice were i.v. administered two amounts (15.5 MBq; 3 mg/kg) of [111In]In-Bn-DTPA-Nimotuzumab separated by 14 days. Control mice received unlabeled Bn-DTPA-Nimotuzumab (3 mg/kg) or anti-HER2 [111In]In-Bn-DTPA-trastuzumab or normal saline. Tumor growth and body weight were measured for 6 weeks. A tumor growth index (TGI) and body weight index (BWI) were calculated to compare the tumor size and body weight post-treatment with the pre-treatment values. A tumor doubling ratio (TDR) was calculated for each treatment group compared to control mice receiving normal saline. Results There was no loss of body weight or decreased red blood cells (RBC) or platelets (PLT) or increased serum ALT or Cr in Balb/c mice administered 9.0 or 28.6 MBq (3 mg/kg) of [111In]In-Bn-DTPA-Nimotuzumab compared to mice treated with unlabeled Bn-DTPA-Nimotuzumab (3 mg/kg) or normal saline. There was a significant decrease in white blood cell (WBC) counts in Balb/c mice receiving 28.6 MBq but not 9.0 MBq of [111In]In-Bn-DTPA-Nimotuzumab. Based on these results, an administered amount of 15.5 MBq (3 mg/kg) was selected for RIT studies. Administration of two amounts (15.5 MBq; 3 mg/kg) separated by 14 days to CD-1 athymic mice with s.c. MDA-MB-468 xenografts strongly inhibited tumor growth. The TDR for mice treated with [111In]In-Bn-DTPA-Nimotuzumab was 2.15 compared to control mice receiving normal saline. In contrast, treatment with unlabeled Bn-DTPA-Nimotuzumab or [111In]In-Bn-DTPA-trastuzumab had no significant effect on tumor growth (TDR = 0.96 and 1.08, respectively). RIT with [111In]In-Bn-DTPA-Nimotuzumab also strongly inhibited the growth of TrR1 tumors in athymic mice (TDR = 2.13) compared to unlabeled Bn-DTPA-Nimotuzumab (TDR = 0.91). There were no losses in body weight over 6 weeks in tumor bearing mice receiving [111In]In-Bn-DTPA-Nimotuzumab, unlabeled Bn-DTPA-Nimotuzumab, [111In]In-Bn-DTPA-trastuzumab or normal saline. Conclusions [111In]In-Bn-DTPA-Nimotuzumab was effective for treatment of TNBC or trastuzumab-resistant HER2-positive human BC tumors in mice that overexpress EGFR at administered amounts that caused no decrease in body weight or normal tissue toxicity in non-tumor-bearing Balb/c mice. Advances in knowledge and implications for patient care Our results suggest that Auger electron RIT with [111In]In-Bn-DTPA-Nimotuzumab may provide a novel therapeutic option for patients with TNBC or trastuzumab-resistant HER2-positive BC that overexpresses EGFR. The low normal tissue toxicity of this approach may allow combination with other targeted therapies such as antibody-drug conjugates (ADCs).
-
111in bn dtpa Nimotuzumab with without modification with nuclear translocation sequence nls peptides an auger electron emitting radioimmunotherapeutic agent for egfr positive and trastuzumab herceptin resistant breast cancer
Breast Cancer Research and Treatment, 2012Co-Authors: Aisha Fasih, Humphrey Fonge, Raymond M Reilly, Ilia Tikhomirov, Zhongli Cai, Jeffrey V Leyton, Susan J DoneAbstract:Increased expression of epidermal growth factor receptors (EGFR) in breast cancer (BC) is often associated with trastuzumab (Herceptin)-resistant forms of the disease and represents an attractive target for novel therapies. Nimotuzumab is a humanized IgG1 monoclonal antibody that is in clinical trials for treatment of EGFR-overexpressing malignancies. We show here that Nimotuzumab derivatized with benzylisothiocyanate diethylenetriaminepentaacetic acid for labelling with the subcellular range Auger electron-emitter, 111In and modified with nuclear translocation sequence (NLS) peptides (111In-NLS-Bn-DTPA-Nimotuzumab) was bound, internalized and transported to the nucleus of EGFR-positive BC cells. Emission of Auger electrons in close proximity to the nucleus caused multiple DNA double-strand breaks which diminished the clonogenic survival (CS) of MDA-MB-468 cells that have high EGFR density (2.4 × 106 receptors/cell) to less than 3 %. 111In-Bn-DTPA-Nimotuzumab without NLS peptide modification was sevenfold less effective for killing MDA-MB-468 cells. 111In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification were equivalently cytotoxic to MDA-MB-231 and TrR1 BC cells that have moderate EGFR density (5.4 × 105 or 4.2 × 105 receptors/cell, respectively) reducing their CS by twofold. MDA-MB-231 cells have intrinsic trastuzumab resistance due to low HER2 density, whereas TrR1 cells have acquired resistance despite HER2 overexpression. Biodistribution and microSPECT/CT imaging revealed that 111In-NLS-Bn-DTPA-Nimotuzumab exhibited more rapid elimination from the blood and lower tumour uptake than 111In-Bn-DTPA-Nimotuzumab. Tumour uptake of the radioimmunoconjugates in mice with MDA-MB-468 xenografts was high (8–16 % injected dose/g) and was blocked by administration of an excess of unlabelled Nimotuzumab, demonstrating EGFR specificity. We conclude that 111In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification are promising Auger electron-emitting radioimmunotherapeutic agents for EGFR-positive BC, but 111In-Bn-DTPA-Nimotuzumab may be preferred due to its higher tumour uptake in vivo.
-
in bn dtpa Nimotuzumab with without modification with nuclear translocation sequence nls peptides an auger electron emitting radioimmunotherapeutic agent for egfr positive and trastuzumab herceptin resistant breast cancer
Breast Cancer Research and Treatment, 2012Co-Authors: Aisha Fasih, Humphrey Fonge, Raymond M Reilly, Ilia Tikhomirov, Zhongli Cai, Jeffrey V Leyton, Susan J DoneAbstract:Increased expression of epidermal growth factor receptors (EGFR) in breast cancer (BC) is often associated with trastuzumab (Herceptin)-resistant forms of the disease and represents an attractive target for novel therapies. Nimotuzumab is a humanized IgG(1) monoclonal antibody that is in clinical trials for treatment of EGFR-overexpressing malignancies. We show here that Nimotuzumab derivatized with benzylisothiocyanate diethylenetriaminepentaacetic acid for labelling with the subcellular range Auger electron-emitter, (111)In and modified with nuclear translocation sequence (NLS) peptides ((111)In-NLS-Bn-DTPA-Nimotuzumab) was bound, internalized and transported to the nucleus of EGFR-positive BC cells. Emission of Auger electrons in close proximity to the nucleus caused multiple DNA double-strand breaks which diminished the clonogenic survival (CS) of MDA-MB-468 cells that have high EGFR density (2.4 × 10(6) receptors/cell) to less than 3 %. (111)In-Bn-DTPA-Nimotuzumab without NLS peptide modification was sevenfold less effective for killing MDA-MB-468 cells. (111)In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification were equivalently cytotoxic to MDA-MB-231 and TrR1 BC cells that have moderate EGFR density (5.4 × 10(5) or 4.2 × 10(5) receptors/cell, respectively) reducing their CS by twofold. MDA-MB-231 cells have intrinsic trastuzumab resistance due to low HER2 density, whereas TrR1 cells have acquired resistance despite HER2 overexpression. Biodistribution and microSPECT/CT imaging revealed that (111)In-NLS-Bn-DTPA-Nimotuzumab exhibited more rapid elimination from the blood and lower tumour uptake than (111)In-Bn-DTPA-Nimotuzumab. Tumour uptake of the radioimmunoconjugates in mice with MDA-MB-468 xenografts was high (8-16 % injected dose/g) and was blocked by administration of an excess of unlabelled Nimotuzumab, demonstrating EGFR specificity. We conclude that (111)In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification are promising Auger electron-emitting radioimmunotherapeutic agents for EGFR-positive BC, but (111)In-Bn-DTPA-Nimotuzumab may be preferred due to its higher tumour uptake in vivo.
Humphrey Fonge - One of the best experts on this subject based on the ideXlab platform.
-
effectiveness and normal tissue toxicity of auger electron ae radioimmunotherapy rit with 111in in bn dtpa Nimotuzumab in mice with triple negative or trastuzumab resistant human breast cancer xenografts that overexpress egfr
Nuclear Medicine and Biology, 2020Co-Authors: Conrad Chan, Humphrey Fonge, Karen Lam, Raymond M ReillyAbstract:Abstract Introduction Our objective was to evaluate the effectiveness and normal tissue toxicity of Nimotuzumab labeled with the Auger electron (AE)-emitter, 111In ([111In]In-Bn-DTPA-Nimotuzumab) for radioimmunotherapy (RIT) of human triple-negative breast cancer (TNBC) or trastuzumab-resistant HER2-positive BC tumors overexpressing epidermal growth factor receptors (EGFR) in athymic mice. Methods Normal tissue toxicity was studied in non-tumor-bearing Balb/c mice i.v. administered 9.0 or 28.6 MBq (3 mg/kg) of [111In]In-Bn-DTPA-Nimotuzumab, unlabeled Nimotuzumab (3 mg/kg) or normal saline. A complete blood cell count (CBC) and serum alanine aminotransferase (ALT) and creatinine (Cr) were measured at 14 days. Body weight was monitored. RIT studies were performed in CD-1 athymic mice engrafted s.c. with MDA-MB-468 human TNBC tumors or TrR1 HER2-positive but trastuzumab-resistant BC tumors. Mice were i.v. administered two amounts (15.5 MBq; 3 mg/kg) of [111In]In-Bn-DTPA-Nimotuzumab separated by 14 days. Control mice received unlabeled Bn-DTPA-Nimotuzumab (3 mg/kg) or anti-HER2 [111In]In-Bn-DTPA-trastuzumab or normal saline. Tumor growth and body weight were measured for 6 weeks. A tumor growth index (TGI) and body weight index (BWI) were calculated to compare the tumor size and body weight post-treatment with the pre-treatment values. A tumor doubling ratio (TDR) was calculated for each treatment group compared to control mice receiving normal saline. Results There was no loss of body weight or decreased red blood cells (RBC) or platelets (PLT) or increased serum ALT or Cr in Balb/c mice administered 9.0 or 28.6 MBq (3 mg/kg) of [111In]In-Bn-DTPA-Nimotuzumab compared to mice treated with unlabeled Bn-DTPA-Nimotuzumab (3 mg/kg) or normal saline. There was a significant decrease in white blood cell (WBC) counts in Balb/c mice receiving 28.6 MBq but not 9.0 MBq of [111In]In-Bn-DTPA-Nimotuzumab. Based on these results, an administered amount of 15.5 MBq (3 mg/kg) was selected for RIT studies. Administration of two amounts (15.5 MBq; 3 mg/kg) separated by 14 days to CD-1 athymic mice with s.c. MDA-MB-468 xenografts strongly inhibited tumor growth. The TDR for mice treated with [111In]In-Bn-DTPA-Nimotuzumab was 2.15 compared to control mice receiving normal saline. In contrast, treatment with unlabeled Bn-DTPA-Nimotuzumab or [111In]In-Bn-DTPA-trastuzumab had no significant effect on tumor growth (TDR = 0.96 and 1.08, respectively). RIT with [111In]In-Bn-DTPA-Nimotuzumab also strongly inhibited the growth of TrR1 tumors in athymic mice (TDR = 2.13) compared to unlabeled Bn-DTPA-Nimotuzumab (TDR = 0.91). There were no losses in body weight over 6 weeks in tumor bearing mice receiving [111In]In-Bn-DTPA-Nimotuzumab, unlabeled Bn-DTPA-Nimotuzumab, [111In]In-Bn-DTPA-trastuzumab or normal saline. Conclusions [111In]In-Bn-DTPA-Nimotuzumab was effective for treatment of TNBC or trastuzumab-resistant HER2-positive human BC tumors in mice that overexpress EGFR at administered amounts that caused no decrease in body weight or normal tissue toxicity in non-tumor-bearing Balb/c mice. Advances in knowledge and implications for patient care Our results suggest that Auger electron RIT with [111In]In-Bn-DTPA-Nimotuzumab may provide a novel therapeutic option for patients with TNBC or trastuzumab-resistant HER2-positive BC that overexpresses EGFR. The low normal tissue toxicity of this approach may allow combination with other targeted therapies such as antibody-drug conjugates (ADCs).
-
Therapeutic potential of Nimotuzumab PEGylated-maytansine antibody drug conjugates against EGFR positive xenograft
Oncotarget, 2019Co-Authors: Siddesh V. Hartimath, Wendy Bernhard, Wayne Hill, Angel Casaco Parada, Kris Barreto, Clarence Ronald Geyer, Ayman El-sayed, Amal Makhlouf, Carolina Gonzalez, Humphrey FongeAbstract:Nimotuzumab is a humanized anti-epidermal growth factor receptor I (EGFR) monoclonal antibody. We have developed antibody drug conjugates (ADCs) with Nimotuzumab conjugated to PEGylated-maytansine (PEG6-DM1). We generated conjugates with low (Nimotuzumab-PEG6-DM1-Low: DAR = 3.5) and high (Nimotuzumab-PEG6-DM1-High: DAR = 7.3) drug to antibody ratios (DAR). Quality control was performed using UV spectrophotometry, size exclusion HPLC, bioanalyzer, biolayer interferometry (BLI), and flow cytometry in EGFR-positive DLD-1, MDA-MB-468 (high density EGFR), and HT-29 (very low EGFR density) cells. Control antibody drug conjugates were developed using a human anti-maltose binding protein (MBP) antibody. BLI showed that the binding of Nimotuzumab-PEG6-DM1-Low and Nimotuzumab-PEG6-DM1-High was slightly but significantly affected by conjugation of the drug (Nimotuzumab KD 0.89 ± 0.02 nM < Nimotuzumab-PEG6-DM1-Low KD 1.94 ± 0.02 nM < Nimotuzumab-PEG6-DM1-High KD 3.75 ± 0.03 nM). In vitro cytotoxicity was determined following incubation of cells with the immunoconjugates and IC50 values were determined. Nimotuzumab-PEG6-DM1-Low and Nimotuzumab-PEG6-DM1-High were used to treat EGFR positive KRAS mutant DLD-1 colorectal cancer xenograft. DLD-1 cells were transduced with a red fluorescent protein (iRFP702) to allow the use of near infrared imaging (NIR) for tumor response monitoring. In vitro potency correlated with the number of drugs on antibody, with Nimotuzumab-PEG6-DM1-High showing higher activity than Nimotuzumab-PEG6-DM1-Low. Three doses (15 mg/kg) of the ADCs prolonged the survival of DLD-1-iRFP-702 tumor bearing mice as monitored by NIR. Nimotuzumab-PEG6-DM1-Low resulted in 4/6 complete cure while Nimotuzumab-PEG6-DM1-High resulted in 2/5 complete cure. The novel ADCs were very effective in a colorectal cancer model in vivo.
-
Preclinical Evaluation of 111In-Labeled PEGylated Maytansine Nimotuzumab Drug Conjugates in EGFR-Positive Cancer Models.
Journal of nuclear medicine : official publication Society of Nuclear Medicine, 2019Co-Authors: Siddesh V. Hartimath, Elahe Alizadeh, Viswas Raja Solomon, Rufael Chekol, Wendy Bernhard, Wayne Hill, Angel Casaco Parada, Kris Barreto, Clarence Ronald Geyer, Humphrey FongeAbstract:Epidermal growth factor receptor I (EGFR) is overexpressed in most cancers of epithelial origin. Antibody drug conjugates (ADCs) with PEGylated-maytansine (PEG-DM1) show promise in vitro and in vivo. However, in vivo biodistribution data for ADCs with PEG-DM1 have not been reported. Development of methods to understand the real-time in vivo behavior of these ADCs is needed to move these compounds to the clinic. Methods: Here we have used noninvasive small-animal SPECT/CT imaging and ex vivo biodistribution to understand the in vivo behavior of PEG6-DM1 ADCs. We developed Nimotuzumab ADCs conjugated to PEG6-DM1. We generated immunoconjugates with low (Nimotuzumab-PEG6-DM1-Low) and high (Nimotuzumab-PEG6-DM1-High) drug-to-antibody ratios. The drug-to-antibody of Nimotuzumab-PEG6-DM1-Low and Nimotuzumab-PEG6-DM1-High was 3.5 and 7.3, respectively. Quality control was performed using ultraviolet spectrophotometry, size-exclusion high-performance liquid chromatography, bioanalyzer, biolayer interferometry, and flow cytometry in EGFR-positive DLD-1 cells. These immunoconjugates were conjugated with DOTA and radiolabeled with 111In. The in vitro binding and internalization rates of 111In-Nimotuzumab, 111In-Nimotuzumab-PEG6-DM1-Low, and 111In-Nimotuzumab-PEG6-DM1-High were characterized. Furthermore, the pharmacokinetics, biodistribution, and imaging characteristics were evaluated in normal and DLD-1 tumor-bearing mice. Results: Flow cytometry and biolayer interferometry showed a trend toward decreasing EGFR affinity with increasing number of PEG6-DM1 on the antibody. Despite the lower overall cellular binding of the PEG6-DM1 radioimmunoconjugates, internalization was higher for PEG6-DM1 ADCs than for the non-PEGylated ADC in the following order: 111In-Nimotuzumab-PEG6-DM1-High > 111In-Nimotuzumab-PEG6-DM1-Low > 111In-Nimotuzumab. Nuclear uptake of 111In-Nimotuzumab-PEG6-DM1-High was 4.4-fold higher than 111In-Nimotuzumab. Pharmacokinetics and biodistribution showed that 111In-Nimotuzumab-PEG6-DM1-High had the slowest blood and whole-body clearance rate. Uptake in DLD-1 tumors of 111In-Nimotuzumab was similar to 111In-Nimotuzumab-PEG6-DM1-Low but was significantly higher than for 111In-Nimotuzumab-PEG6-DM1-High. Tumor-to-background ratios for 111In-Nimotuzumab and 111In-Nimotuzumab-PEG6-DM1-Low were higher than for 111In-Nimotuzumab-PEG6-DM1-High. Conclusion: The results show that conjugation of multiple PEG6-DM1 reduces the affinity for EGFR in vitro. However, the reduced affinity is counteracted by the high internalization rate of constructs with PEG6-DM1 ADCs in vitro. The decreased affinity resulted in low tumor uptake of 111In-Nimotuzumab-PEG6-DM1-High, with a slow overall whole-body clearance rate. These data provide insights for evaluating the pharmacokinetics and normal -tissue toxicity and in determining dosing rate of PEGylated ADCs.
-
Near infrared fluorescence imaging of EGFR expression in vivo using IRDye800CW-Nimotuzumab
Oncotarget, 2017Co-Authors: Wendy Bernhard, Humphrey Fonge, Wayne Hill, Angel Casaco Parada, Kris Barreto, Ayman El-sayed, Carolina Gonzalez, C. Ronald GeyerAbstract:Nimotuzumab is a humanized anti-epidermal growth factor receptor (EGFR) monoclonal antibody that is approved in many countries for the treatment of EGFR-positive cancers. Near infrared (NIR) fluorescent dye-labeled antibodies represent an attractive class of image-guided surgical probes because of their high specificity, tumor uptake, and low dissociation from tumor cells that express the antigen. In this study, we developed a NIR fluorescent dye-labeled Nimotuzumab immunoconjugate, IRDye800CW-Nimotuzumab, and evaluated in vitro binding with EGFR-positive cells, in vivo tumor uptake by NIR fluorescent imaging, and ex vivo biodistribution. There was no difference in binding between Nimotuzumab and IRDye800CW-Nimotuzumab to EGFR-positive cells. In mice bearing EGFR-positive xenografts, IRDye800CW-Nimotuzumab uptake peaked at 4 days post injection and slowly decreased thereafter with high levels of accumulation still observed at 28 days post injection. In EGFR-positive xenografts, IRDye800CW-Nimotuzumab showed more than 2-fold higher uptake in tumors compared to IRDye800CW-cetuximab. In addition, liver uptake of IRDye800CW-Nimotuzumab was two-fold lower than cetuximab. The lower liver uptake of IRDye800CW-Nimotuzumab could have implications on the selected dose for clinical trials of the immunoconjugate. In summary, this study shows that Nimotuzumab is a good candidate for NIR fluorescent imaging and image-guided surgery.
-
111in bn dtpa Nimotuzumab with without modification with nuclear translocation sequence nls peptides an auger electron emitting radioimmunotherapeutic agent for egfr positive and trastuzumab herceptin resistant breast cancer
Breast Cancer Research and Treatment, 2012Co-Authors: Aisha Fasih, Humphrey Fonge, Raymond M Reilly, Ilia Tikhomirov, Zhongli Cai, Jeffrey V Leyton, Susan J DoneAbstract:Increased expression of epidermal growth factor receptors (EGFR) in breast cancer (BC) is often associated with trastuzumab (Herceptin)-resistant forms of the disease and represents an attractive target for novel therapies. Nimotuzumab is a humanized IgG1 monoclonal antibody that is in clinical trials for treatment of EGFR-overexpressing malignancies. We show here that Nimotuzumab derivatized with benzylisothiocyanate diethylenetriaminepentaacetic acid for labelling with the subcellular range Auger electron-emitter, 111In and modified with nuclear translocation sequence (NLS) peptides (111In-NLS-Bn-DTPA-Nimotuzumab) was bound, internalized and transported to the nucleus of EGFR-positive BC cells. Emission of Auger electrons in close proximity to the nucleus caused multiple DNA double-strand breaks which diminished the clonogenic survival (CS) of MDA-MB-468 cells that have high EGFR density (2.4 × 106 receptors/cell) to less than 3 %. 111In-Bn-DTPA-Nimotuzumab without NLS peptide modification was sevenfold less effective for killing MDA-MB-468 cells. 111In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification were equivalently cytotoxic to MDA-MB-231 and TrR1 BC cells that have moderate EGFR density (5.4 × 105 or 4.2 × 105 receptors/cell, respectively) reducing their CS by twofold. MDA-MB-231 cells have intrinsic trastuzumab resistance due to low HER2 density, whereas TrR1 cells have acquired resistance despite HER2 overexpression. Biodistribution and microSPECT/CT imaging revealed that 111In-NLS-Bn-DTPA-Nimotuzumab exhibited more rapid elimination from the blood and lower tumour uptake than 111In-Bn-DTPA-Nimotuzumab. Tumour uptake of the radioimmunoconjugates in mice with MDA-MB-468 xenografts was high (8–16 % injected dose/g) and was blocked by administration of an excess of unlabelled Nimotuzumab, demonstrating EGFR specificity. We conclude that 111In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification are promising Auger electron-emitting radioimmunotherapeutic agents for EGFR-positive BC, but 111In-Bn-DTPA-Nimotuzumab may be preferred due to its higher tumour uptake in vivo.
Susan J Done - One of the best experts on this subject based on the ideXlab platform.
-
111in bn dtpa Nimotuzumab with without modification with nuclear translocation sequence nls peptides an auger electron emitting radioimmunotherapeutic agent for egfr positive and trastuzumab herceptin resistant breast cancer
Breast Cancer Research and Treatment, 2012Co-Authors: Aisha Fasih, Humphrey Fonge, Raymond M Reilly, Ilia Tikhomirov, Zhongli Cai, Jeffrey V Leyton, Susan J DoneAbstract:Increased expression of epidermal growth factor receptors (EGFR) in breast cancer (BC) is often associated with trastuzumab (Herceptin)-resistant forms of the disease and represents an attractive target for novel therapies. Nimotuzumab is a humanized IgG1 monoclonal antibody that is in clinical trials for treatment of EGFR-overexpressing malignancies. We show here that Nimotuzumab derivatized with benzylisothiocyanate diethylenetriaminepentaacetic acid for labelling with the subcellular range Auger electron-emitter, 111In and modified with nuclear translocation sequence (NLS) peptides (111In-NLS-Bn-DTPA-Nimotuzumab) was bound, internalized and transported to the nucleus of EGFR-positive BC cells. Emission of Auger electrons in close proximity to the nucleus caused multiple DNA double-strand breaks which diminished the clonogenic survival (CS) of MDA-MB-468 cells that have high EGFR density (2.4 × 106 receptors/cell) to less than 3 %. 111In-Bn-DTPA-Nimotuzumab without NLS peptide modification was sevenfold less effective for killing MDA-MB-468 cells. 111In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification were equivalently cytotoxic to MDA-MB-231 and TrR1 BC cells that have moderate EGFR density (5.4 × 105 or 4.2 × 105 receptors/cell, respectively) reducing their CS by twofold. MDA-MB-231 cells have intrinsic trastuzumab resistance due to low HER2 density, whereas TrR1 cells have acquired resistance despite HER2 overexpression. Biodistribution and microSPECT/CT imaging revealed that 111In-NLS-Bn-DTPA-Nimotuzumab exhibited more rapid elimination from the blood and lower tumour uptake than 111In-Bn-DTPA-Nimotuzumab. Tumour uptake of the radioimmunoconjugates in mice with MDA-MB-468 xenografts was high (8–16 % injected dose/g) and was blocked by administration of an excess of unlabelled Nimotuzumab, demonstrating EGFR specificity. We conclude that 111In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification are promising Auger electron-emitting radioimmunotherapeutic agents for EGFR-positive BC, but 111In-Bn-DTPA-Nimotuzumab may be preferred due to its higher tumour uptake in vivo.
-
in bn dtpa Nimotuzumab with without modification with nuclear translocation sequence nls peptides an auger electron emitting radioimmunotherapeutic agent for egfr positive and trastuzumab herceptin resistant breast cancer
Breast Cancer Research and Treatment, 2012Co-Authors: Aisha Fasih, Humphrey Fonge, Raymond M Reilly, Ilia Tikhomirov, Zhongli Cai, Jeffrey V Leyton, Susan J DoneAbstract:Increased expression of epidermal growth factor receptors (EGFR) in breast cancer (BC) is often associated with trastuzumab (Herceptin)-resistant forms of the disease and represents an attractive target for novel therapies. Nimotuzumab is a humanized IgG(1) monoclonal antibody that is in clinical trials for treatment of EGFR-overexpressing malignancies. We show here that Nimotuzumab derivatized with benzylisothiocyanate diethylenetriaminepentaacetic acid for labelling with the subcellular range Auger electron-emitter, (111)In and modified with nuclear translocation sequence (NLS) peptides ((111)In-NLS-Bn-DTPA-Nimotuzumab) was bound, internalized and transported to the nucleus of EGFR-positive BC cells. Emission of Auger electrons in close proximity to the nucleus caused multiple DNA double-strand breaks which diminished the clonogenic survival (CS) of MDA-MB-468 cells that have high EGFR density (2.4 × 10(6) receptors/cell) to less than 3 %. (111)In-Bn-DTPA-Nimotuzumab without NLS peptide modification was sevenfold less effective for killing MDA-MB-468 cells. (111)In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification were equivalently cytotoxic to MDA-MB-231 and TrR1 BC cells that have moderate EGFR density (5.4 × 10(5) or 4.2 × 10(5) receptors/cell, respectively) reducing their CS by twofold. MDA-MB-231 cells have intrinsic trastuzumab resistance due to low HER2 density, whereas TrR1 cells have acquired resistance despite HER2 overexpression. Biodistribution and microSPECT/CT imaging revealed that (111)In-NLS-Bn-DTPA-Nimotuzumab exhibited more rapid elimination from the blood and lower tumour uptake than (111)In-Bn-DTPA-Nimotuzumab. Tumour uptake of the radioimmunoconjugates in mice with MDA-MB-468 xenografts was high (8-16 % injected dose/g) and was blocked by administration of an excess of unlabelled Nimotuzumab, demonstrating EGFR specificity. We conclude that (111)In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification are promising Auger electron-emitting radioimmunotherapeutic agents for EGFR-positive BC, but (111)In-Bn-DTPA-Nimotuzumab may be preferred due to its higher tumour uptake in vivo.
Ilia Tikhomirov - One of the best experts on this subject based on the ideXlab platform.
-
111in bn dtpa Nimotuzumab with without modification with nuclear translocation sequence nls peptides an auger electron emitting radioimmunotherapeutic agent for egfr positive and trastuzumab herceptin resistant breast cancer
Breast Cancer Research and Treatment, 2012Co-Authors: Aisha Fasih, Humphrey Fonge, Raymond M Reilly, Ilia Tikhomirov, Zhongli Cai, Jeffrey V Leyton, Susan J DoneAbstract:Increased expression of epidermal growth factor receptors (EGFR) in breast cancer (BC) is often associated with trastuzumab (Herceptin)-resistant forms of the disease and represents an attractive target for novel therapies. Nimotuzumab is a humanized IgG1 monoclonal antibody that is in clinical trials for treatment of EGFR-overexpressing malignancies. We show here that Nimotuzumab derivatized with benzylisothiocyanate diethylenetriaminepentaacetic acid for labelling with the subcellular range Auger electron-emitter, 111In and modified with nuclear translocation sequence (NLS) peptides (111In-NLS-Bn-DTPA-Nimotuzumab) was bound, internalized and transported to the nucleus of EGFR-positive BC cells. Emission of Auger electrons in close proximity to the nucleus caused multiple DNA double-strand breaks which diminished the clonogenic survival (CS) of MDA-MB-468 cells that have high EGFR density (2.4 × 106 receptors/cell) to less than 3 %. 111In-Bn-DTPA-Nimotuzumab without NLS peptide modification was sevenfold less effective for killing MDA-MB-468 cells. 111In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification were equivalently cytotoxic to MDA-MB-231 and TrR1 BC cells that have moderate EGFR density (5.4 × 105 or 4.2 × 105 receptors/cell, respectively) reducing their CS by twofold. MDA-MB-231 cells have intrinsic trastuzumab resistance due to low HER2 density, whereas TrR1 cells have acquired resistance despite HER2 overexpression. Biodistribution and microSPECT/CT imaging revealed that 111In-NLS-Bn-DTPA-Nimotuzumab exhibited more rapid elimination from the blood and lower tumour uptake than 111In-Bn-DTPA-Nimotuzumab. Tumour uptake of the radioimmunoconjugates in mice with MDA-MB-468 xenografts was high (8–16 % injected dose/g) and was blocked by administration of an excess of unlabelled Nimotuzumab, demonstrating EGFR specificity. We conclude that 111In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification are promising Auger electron-emitting radioimmunotherapeutic agents for EGFR-positive BC, but 111In-Bn-DTPA-Nimotuzumab may be preferred due to its higher tumour uptake in vivo.
-
in bn dtpa Nimotuzumab with without modification with nuclear translocation sequence nls peptides an auger electron emitting radioimmunotherapeutic agent for egfr positive and trastuzumab herceptin resistant breast cancer
Breast Cancer Research and Treatment, 2012Co-Authors: Aisha Fasih, Humphrey Fonge, Raymond M Reilly, Ilia Tikhomirov, Zhongli Cai, Jeffrey V Leyton, Susan J DoneAbstract:Increased expression of epidermal growth factor receptors (EGFR) in breast cancer (BC) is often associated with trastuzumab (Herceptin)-resistant forms of the disease and represents an attractive target for novel therapies. Nimotuzumab is a humanized IgG(1) monoclonal antibody that is in clinical trials for treatment of EGFR-overexpressing malignancies. We show here that Nimotuzumab derivatized with benzylisothiocyanate diethylenetriaminepentaacetic acid for labelling with the subcellular range Auger electron-emitter, (111)In and modified with nuclear translocation sequence (NLS) peptides ((111)In-NLS-Bn-DTPA-Nimotuzumab) was bound, internalized and transported to the nucleus of EGFR-positive BC cells. Emission of Auger electrons in close proximity to the nucleus caused multiple DNA double-strand breaks which diminished the clonogenic survival (CS) of MDA-MB-468 cells that have high EGFR density (2.4 × 10(6) receptors/cell) to less than 3 %. (111)In-Bn-DTPA-Nimotuzumab without NLS peptide modification was sevenfold less effective for killing MDA-MB-468 cells. (111)In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification were equivalently cytotoxic to MDA-MB-231 and TrR1 BC cells that have moderate EGFR density (5.4 × 10(5) or 4.2 × 10(5) receptors/cell, respectively) reducing their CS by twofold. MDA-MB-231 cells have intrinsic trastuzumab resistance due to low HER2 density, whereas TrR1 cells have acquired resistance despite HER2 overexpression. Biodistribution and microSPECT/CT imaging revealed that (111)In-NLS-Bn-DTPA-Nimotuzumab exhibited more rapid elimination from the blood and lower tumour uptake than (111)In-Bn-DTPA-Nimotuzumab. Tumour uptake of the radioimmunoconjugates in mice with MDA-MB-468 xenografts was high (8-16 % injected dose/g) and was blocked by administration of an excess of unlabelled Nimotuzumab, demonstrating EGFR specificity. We conclude that (111)In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification are promising Auger electron-emitting radioimmunotherapeutic agents for EGFR-positive BC, but (111)In-Bn-DTPA-Nimotuzumab may be preferred due to its higher tumour uptake in vivo.
-
bivalent binding by intermediate affinity of Nimotuzumab a contribution to explain antibody clinical profile
Cancer Biology & Therapy, 2011Co-Authors: Greta Garrido, Ailem Rabasa, Tania Crombet, Ilia Tikhomirov, Eric V Yang, Elias Gracia, Normando Iznaga, Luis E Fernandez, Robert S Kerbel, Rolando PerezAbstract:Nimotuzumab is an EGFR-targeting antibody that has demonstrated encouraging clinical results in the absence of severe side-effects observed with other approved anti-EGFR antibodies. We investigated whether different clinical behavior of Nimotuzumab is related to its bivalent/monovalent binding profile. Binding properties of Nimotuzumab and cetuximab, the most development of anti-EGFR antibodies, were studied in vitro using chip surfaces and cells with varying EGFR expression levels. Experimental observations demonstrated that in contrast to cetuximab, the intrinsic properties of Nimotuzumab required bivalent binding for stable attachment to the cellular surface, leading to Nimotuzumab selectively binding to cells that express moderate to high EGFR expression levels. At these conditions, both antibodies bound bivalently, and accumulated to similar degrees. When EGFR density is low, Nimotuzumab monovalent interaction was transient, whereas cetuximab continued to interact strongly with the receptors. We compared the in vitro anti-tumor efficacy of Nimotuzumab and cetuximab. Cetuximab decreased the cell viability and induced apoptosis for all the tested cell lines, effects which did not depend on EGFR expression level. In contrast, Nimotuzumab also provoked significant anti-cellular effects, but its anti-tumor capacity decreased together with EGFR expression level. Cetuximab Fab fragment was able to impact tumor cell survival, whereas Nimotuzumab fragment totally lost this effect. Tumor-xenograft experiments using cells with a high EGFR expression revealed similar tumor growth inhibiting effects for both antibodies. This study suggests an explanation for Nimotuzumab clinical profile, whereby anti-tumor activity is obtained in absence of severe toxicities due to its properties of bivalent binding to EGFR.
-
bivalent binding by intermediate affinity of Nimotuzumab a contribution to explain antibody clinical profile
Cancer Biology & Therapy, 2011Co-Authors: Greta Garrido, Ailem Rabasa, Tania Crombet, Ilia Tikhomirov, Eric V Yang, Elias Gracia, Normando Iznaga, Luis E Fernandez, Robert S Kerbel, Rolando PerezAbstract:Nimotuzumab is an EGFR-targeting antibody that has demonstrated encouraging clinical results in the absence of severe side-effects observed with other approved anti-EGFR antibodies. We investigated whether different clinical behavior of Nimotuzumab is related to its bivalent/monovalent binding profile. Binding properties of Nimotuzumab and cetuximab, the most development of anti-EGFR antibodies, were studied in vitro using chip surfaces and cells with varying EGFR expression levels. Experimental observations demonstrated that in contrast to cetuximab, the intrinsic properties of Nimotuzumab required bivalent binding for stable attachment to the cellular surface, leading to Nimotuzumab selectively binding to cells that express moderate to high EGFR expression levels. At these conditions, both antibodies bound bivalently, and accumulated to similar degrees. When EGFR density is low, Nimotuzumab monovalent interaction was transient, whereas cetuximab continued to interact strongly with the receptors. We comp...
Aisha Fasih - One of the best experts on this subject based on the ideXlab platform.
-
111in bn dtpa Nimotuzumab with without modification with nuclear translocation sequence nls peptides an auger electron emitting radioimmunotherapeutic agent for egfr positive and trastuzumab herceptin resistant breast cancer
Breast Cancer Research and Treatment, 2012Co-Authors: Aisha Fasih, Humphrey Fonge, Raymond M Reilly, Ilia Tikhomirov, Zhongli Cai, Jeffrey V Leyton, Susan J DoneAbstract:Increased expression of epidermal growth factor receptors (EGFR) in breast cancer (BC) is often associated with trastuzumab (Herceptin)-resistant forms of the disease and represents an attractive target for novel therapies. Nimotuzumab is a humanized IgG1 monoclonal antibody that is in clinical trials for treatment of EGFR-overexpressing malignancies. We show here that Nimotuzumab derivatized with benzylisothiocyanate diethylenetriaminepentaacetic acid for labelling with the subcellular range Auger electron-emitter, 111In and modified with nuclear translocation sequence (NLS) peptides (111In-NLS-Bn-DTPA-Nimotuzumab) was bound, internalized and transported to the nucleus of EGFR-positive BC cells. Emission of Auger electrons in close proximity to the nucleus caused multiple DNA double-strand breaks which diminished the clonogenic survival (CS) of MDA-MB-468 cells that have high EGFR density (2.4 × 106 receptors/cell) to less than 3 %. 111In-Bn-DTPA-Nimotuzumab without NLS peptide modification was sevenfold less effective for killing MDA-MB-468 cells. 111In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification were equivalently cytotoxic to MDA-MB-231 and TrR1 BC cells that have moderate EGFR density (5.4 × 105 or 4.2 × 105 receptors/cell, respectively) reducing their CS by twofold. MDA-MB-231 cells have intrinsic trastuzumab resistance due to low HER2 density, whereas TrR1 cells have acquired resistance despite HER2 overexpression. Biodistribution and microSPECT/CT imaging revealed that 111In-NLS-Bn-DTPA-Nimotuzumab exhibited more rapid elimination from the blood and lower tumour uptake than 111In-Bn-DTPA-Nimotuzumab. Tumour uptake of the radioimmunoconjugates in mice with MDA-MB-468 xenografts was high (8–16 % injected dose/g) and was blocked by administration of an excess of unlabelled Nimotuzumab, demonstrating EGFR specificity. We conclude that 111In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification are promising Auger electron-emitting radioimmunotherapeutic agents for EGFR-positive BC, but 111In-Bn-DTPA-Nimotuzumab may be preferred due to its higher tumour uptake in vivo.
-
in bn dtpa Nimotuzumab with without modification with nuclear translocation sequence nls peptides an auger electron emitting radioimmunotherapeutic agent for egfr positive and trastuzumab herceptin resistant breast cancer
Breast Cancer Research and Treatment, 2012Co-Authors: Aisha Fasih, Humphrey Fonge, Raymond M Reilly, Ilia Tikhomirov, Zhongli Cai, Jeffrey V Leyton, Susan J DoneAbstract:Increased expression of epidermal growth factor receptors (EGFR) in breast cancer (BC) is often associated with trastuzumab (Herceptin)-resistant forms of the disease and represents an attractive target for novel therapies. Nimotuzumab is a humanized IgG(1) monoclonal antibody that is in clinical trials for treatment of EGFR-overexpressing malignancies. We show here that Nimotuzumab derivatized with benzylisothiocyanate diethylenetriaminepentaacetic acid for labelling with the subcellular range Auger electron-emitter, (111)In and modified with nuclear translocation sequence (NLS) peptides ((111)In-NLS-Bn-DTPA-Nimotuzumab) was bound, internalized and transported to the nucleus of EGFR-positive BC cells. Emission of Auger electrons in close proximity to the nucleus caused multiple DNA double-strand breaks which diminished the clonogenic survival (CS) of MDA-MB-468 cells that have high EGFR density (2.4 × 10(6) receptors/cell) to less than 3 %. (111)In-Bn-DTPA-Nimotuzumab without NLS peptide modification was sevenfold less effective for killing MDA-MB-468 cells. (111)In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification were equivalently cytotoxic to MDA-MB-231 and TrR1 BC cells that have moderate EGFR density (5.4 × 10(5) or 4.2 × 10(5) receptors/cell, respectively) reducing their CS by twofold. MDA-MB-231 cells have intrinsic trastuzumab resistance due to low HER2 density, whereas TrR1 cells have acquired resistance despite HER2 overexpression. Biodistribution and microSPECT/CT imaging revealed that (111)In-NLS-Bn-DTPA-Nimotuzumab exhibited more rapid elimination from the blood and lower tumour uptake than (111)In-Bn-DTPA-Nimotuzumab. Tumour uptake of the radioimmunoconjugates in mice with MDA-MB-468 xenografts was high (8-16 % injected dose/g) and was blocked by administration of an excess of unlabelled Nimotuzumab, demonstrating EGFR specificity. We conclude that (111)In-Bn-DTPA-Nimotuzumab with/without NLS peptide modification are promising Auger electron-emitting radioimmunotherapeutic agents for EGFR-positive BC, but (111)In-Bn-DTPA-Nimotuzumab may be preferred due to its higher tumour uptake in vivo.