PMID- 31242384
OWN - NLM
STAT- MEDLINE
DCOM- 20200625
LR  - 20200625
IS  - 1543-8392 (Electronic)
IS  - 1543-8384 (Linking)
VI  - 16
IP  - 8
DP  - 2019 Aug 5
TI  - MicroSPECT/CT Imaging of Cell-Line and Patient-Derived EGFR-Positive Tumor 
      Xenografts in Mice with Panitumumab Fab Modified with Hexahistidine Peptides To 
      Enable Labeling with (99m)Tc(I) Tricarbonyl Complex.
PG  - 3559-3568
LID - 10.1021/acs.molpharmaceut.9b00422 [doi]
AB  - We aimed to investigate the feasibility of conjugating synthetic hexahistidine 
      peptides (His(6)) peptides to panitumumab Fab (PmFab) to enable labeling with 
      [(99m)Tc(H(2)O)(3)(CO)(3)](+) complex and study these radioimmunoconjugates for 
      imaging EGFR-overexpressing tumor xenografts in mice by microSPECT/CT. Fab were 
      reacted with a 10-fold excess of sulfo-SMCC to introduce maleimide functional 
      groups for reaction with the terminal thiol on peptides [CGYGGHHHHHH] that 
      harbored the His(6) motif. Modification of Fab with His(6) peptides was assessed 
      by SDS-PAGE/Western blot, and the number of His(6) peptides introduced was 
      quantified by a radiometric assay incorporating (123)I-labeled peptides into the 
      conjugation reaction. Radiolabeling was achieved by incubation of PmFab-His(6) in 
      PBS, pH 7.0, with [(99m)Tc(H(2)O)(3)(CO)(3)](+) in a 1.4 MBq/mug ratio. The 
      complex was prepared by adding [(99m)TcO(4)](-) to an Isolink kit (Paul Scherrer 
      Institute). Immunoreactivity was assessed in a direct (saturation) binding assay 
      using MDA-MB-468 human triple-negative breast cancer (TNBC) cells. Tumor and 
      normal tissue uptake and imaging properties of (99m)Tc-PmFab-His(6) (70 mug; 35-40 
      MBq) injected i.v. (tail vein) were compared to irrelevant (99m)Tc-Fab 3913 in 
      NOD/SCID mice engrafted subcutaneously (s.c.) with EGFR-overexpressing MDA-MB-468 
      or PANC-1 human pancreatic ductal carcinoma (PDCa) cell-line derived xenografts 
      (CLX) at 4 and 24 h post injection (p.i.). In addition, tumor imaging studies 
      were performed with (99m)Tc-PmFab-His(6) in mice with patient-derived tumor 
      xenografts (PDX) of TNBC, PDCa, and head and neck squamous cell carcinoma 
      (HNSCC). Biodistribution studies in nontumor bearing Balb/c mice were performed 
      to project the radiation absorbed doses for imaging studies in humans with 
      (99m)Tc-PmFab-His(6). PmFab was derivatized with 0.80 +/- 0.03 His(6) peptides. 
      Western blot and SDS-PAGE confirmed the presence of His(6) peptides. 
      (99m)Tc-PmFab-His(6) was labeled to high radiochemical purity (>/=95%), and the 
      K(d) for binding to EGFR on MDA-MB-468 cells was 5.5 +/- 0.4 x 10(-8) mol/L. Tumor 
      uptake of (99m)Tc-PmFab-His(6) at 24 h p.i. was significantly (P < 0.05) higher 
      than irrelevant (99m)Tc-Fab 3913 in mice with MDA-MB-468 tumors (14.9 +/- 3.1%ID/g 
      vs 3.0 +/- 0.9%ID/g) and in mice with PANC-1 tumors (5.6 +/- 0.6 vs 0.5 +/- 0.1%ID/g). 
      In mice implanted orthotopically in the pancreas with the same PDCa PDX, tumor 
      uptake at 24 h p.i. was 4.2 +/- 0.2%ID/g. Locoregional metastases of these PDCa 
      tumors in the peritoneum exhibited slightly and significantly lower uptake than 
      the primary tumors (3.1 +/- 0.3 vs 4.2 +/- 0.3%ID/g; P = 0.02). In mice implanted 
      with different TNBC or HNSCC PDX, tumor uptake at 24 h p.i. was variable and 
      ranged from 3.7 to 11.4%ID/g and 3.8-14.5%ID/g, respectively. MicroSPECT/CT 
      visualized all CLX and PDX tumor xenografts at 4 and 24 h p.i. Dosimetry 
      estimates revealed that in humans, the whole body dose from administration of 
      740-1110 MBq of (99m)Tc-PmFab-His(6) would be 2-3 mSv, which is less than for a 
      (99m)Tc-medronate bone scan (4 mSv).
FAU - Ku, Anthony
AU  - Ku A
AD  - Department of Pharmaceutical Sciences , University of Toronto , 144 College 
      Street , Toronto , ON M5S 3M2 , Canada.
FAU - Chan, Conrad
AU  - Chan C
AD  - Department of Pharmaceutical Sciences , University of Toronto , 144 College 
      Street , Toronto , ON M5S 3M2 , Canada.
FAU - Aghevlian, Sadaf
AU  - Aghevlian S
AD  - Department of Pharmaceutical Sciences , University of Toronto , 144 College 
      Street , Toronto , ON M5S 3M2 , Canada.
FAU - Cai, Zhongli
AU  - Cai Z
AD  - Department of Pharmaceutical Sciences , University of Toronto , 144 College 
      Street , Toronto , ON M5S 3M2 , Canada.
FAU - Cescon, David
AU  - Cescon D
FAU - Bratman, Scott V
AU  - Bratman SV
FAU - Ailles, Laurie
AU  - Ailles L
FAU - Hedley, David W
AU  - Hedley DW
FAU - Reilly, Raymond M
AU  - Reilly RM
AUID- ORCID: 0000-0003-1038-7993
AD  - Department of Pharmaceutical Sciences , University of Toronto , 144 College 
      Street , Toronto , ON M5S 3M2 , Canada.
AD  - Department of Medical Imaging , University of Toronto , 263 McCaul Street , 
      Toronto , ON M5T 1W7 , Canada.
AD  - Toronto General Research Institute and Joint Department of Medical Imaging , 
      University Health Network , 200 Elizabeth Street , Toronto , ON M5G 2C4 , Canada.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20190711
PL  - United States
TA  - Mol Pharm
JT  - Molecular pharmaceutics
JID - 101197791
RN  - 0 (Antineoplastic Agents, Immunological)
RN  - 0 (His-His-His-His-His-His)
RN  - 0 (Oligopeptides)
RN  - 0 (Organotechnetium Compounds)
RN  - 0 (Radiopharmaceuticals)
RN  - 4QD397987E (Histidine)
RN  - 6A901E312A (Panitumumab)
RN  - EC 2.7.10.1 (EGFR protein, human)
RN  - EC 2.7.10.1 (ErbB Receptors)
SB  - IM
MH  - Animals
MH  - Antineoplastic Agents, Immunological/*administration & 
      dosage/chemistry/pharmacokinetics
MH  - Cell Line, Tumor
MH  - ErbB Receptors/antagonists & inhibitors/metabolism
MH  - Feasibility Studies
MH  - Female
MH  - Histidine/chemistry
MH  - Humans
MH  - Mice
MH  - Molecular Imaging/*methods
MH  - Neoplasms/*diagnostic imaging/pathology
MH  - Oligopeptides/chemistry
MH  - Organotechnetium Compounds/administration & dosage/chemistry/pharmacokinetics
MH  - Panitumumab/administration & dosage/chemistry/pharmacokinetics
MH  - Radiopharmaceuticals/*administration & dosage/chemistry/pharmacokinetics
MH  - Tissue Distribution
MH  - Tomography, Emission-Computed, Single-Photon/methods
MH  - Tomography, X-Ray Computed/methods
MH  - X-Ray Microtomography/methods
MH  - Xenograft Model Antitumor Assays
OTO - NOTNLM
OT  - Tc
OT  - epidermal growth factor receptors (EGFR)
OT  - head and neck squamous cell carcinoma
OT  - pancreatic cancer
OT  - panitumumab
OT  - single photon emission computed tomography (SPECT)
OT  - triple-negative breast cancer
EDAT- 2019/06/27 06:00
MHDA- 2020/06/26 06:00
CRDT- 2019/06/27 06:00
PHST- 2019/06/27 06:00 [pubmed]
PHST- 2020/06/26 06:00 [medline]
PHST- 2019/06/27 06:00 [entrez]
AID - 10.1021/acs.molpharmaceut.9b00422 [doi]
PST - ppublish
SO  - Mol Pharm. 2019 Aug 5;16(8):3559-3568. doi: 10.1021/acs.molpharmaceut.9b00422. 
      Epub 2019 Jul 11.