en Radiation Biology Radiation Biology تحقيق بديع Original Research <div style="text-align: justify;"><span style="font-size:10pt"><span style="text-justify:newspaper"><span style="text-kashida-space:50%"><span style="line-height:119%"><span style="font-family:Calibri"><span style="color:black"><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-US">Background</span></span></span></span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-weight:bold"><span style="language:en-US">:</span></span></span></span></span> <span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">Nowadays, radiolabeled monoclonal antibodies (mAbs) are satisfactorily used for the diagnosis and therapy of different types of cancers. In this study, the human absorbed dose of </span></span></span><span lang="en-US" style="font-size:5.9939pt"><span style="font-family:Calibri"><span style="language:en-US">¹⁷⁷</span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">Lu-Cetuximab-PAMAM was estimated based on the biodistribution data in tumor-bearing mice. </span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-US">Materials and Methods: </span></span></span></span></span></span><span lang="en-US" style="font-size:5.9939pt"><span style="font-family:Calibri"><span style="language:en-US">¹⁷⁷</span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">Lu-DTPA-CHX-Cetuximab-PAMAM was prepared after the conjugation of cetuximab to PAMAM nanoparticles and DTPA-CHX to mAb-PAMAM. The biodistribution of the labeled nano-system was studied in the tumor-bearing nude mice up to 72 h after injection. The absorbed dose of human organs was calculated according to the animals&rsquo; data utilizing the radiation absorbed dose assessment resource (RADAR) and the relative mass extrapolation methods. </span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-US">Results: </span></span></span></span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">The radiolabeled compound, prepared at the optimized conditions, had a radiochemical purity (RCP) of 99.6% &plusmn; 0.4% (P < 0.05).&nbsp; Most of the activity was accumulated in the tumor site (10.14 &plusmn; 0.89; P < 0.05). The liver and the kidneys received the highest absorbed dose with 0.561 and 0.207 mSv/MBq, respectively, which is lesser than the other monoclonal antibodies labeled with </span></span></span><span lang="en-US" style="font-size:5.9939pt"><span style="font-family:Calibri"><span style="language:en-US">¹⁷⁷</span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">Lu. </span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-US">Conclusion: </span></span></span></span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">Considering the special characteristics of </span></span></span><span lang="en-US" style="font-size:5.9939pt"><span style="font-family:Calibri"><span style="language:en-US">¹⁷⁷</span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">Lu-DTPA-CHX-Cetuximab-PAMAM, this radiolabeled nano-system can be considered as a safe and effective radiolabeled compound for treatment of EGFR-expressing tumors.</span></span></span></span></span></span></span></span></span></div> PAMAM, Radiation, Dose, Lutetium-177, anti-EGFR. 817 822 http://ijrr.com/browse.php?a_code=A-10-1-1244&slc_lang=en&sid=1 S. Zolghadri szolghadri@aeoi.org.ir 7900319475328460028430 7900319475328460028430 Yes Radiation Application Research School, Nuclear Science and Technology Research Institute (NSTRI), Tehran, 14155-1339, Iran M. Rabiei 7900319475328460028431 7900319475328460028431 No Radiation Application Research School, Nuclear Science and Technology Research Institute (NSTRI), Tehran, 14155-1339, Iran A. Karimian 7900319475328460028432 7900319475328460028432 No Radiation Application Research School, Nuclear Science and Technology Research Institute (NSTRI), Tehran, 14155-1339, Iran S.M. Hosseini 7900319475328460028433 7900319475328460028433 No Department of Life Science Engineering, Faculty of Modern Science and Technology, Nano Biotechnology Group, University of Tehran, Tehran, 1439957131, Iran