[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-354158-105":59,"doc-detail-354158-en":130},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":123,"head_meta":125,"extra_data":127,"updated_unix":129},105,"en","muc1-targeting-small-peptide-radiopharmaceuticals-for-breast-cancer","MUC1-targeting small peptide radiopharmaceuticals for breast cancer","","Mucin 1 (MUC1) is overexpressed and underglycosylated in epithelial malignancies, including triple-negative breast cancer, exposing the VNTR variable number tandem repeat region. A study evaluated small peptide radiopharmaceuticals derived from three minimal VNTR epitope sequences (RPAPGS, PPAHGVT, PDTRP) and assessed how linker lipophilicity influenced MUC1 binding. Reference compounds showed limited uptake and lacked measurable, specific binding in cell assays, saturation binding, surface plasmon resonance, and in vivo mouse tumor models. Results indicate minimal-epitope peptidomimetics do not yield high-affinity MUC1 binders, motivating new peptide discovery efforts.",{"@graph":69,"@context":122},[70,84,105],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":35,"@type":76,"position":81},"https://docshare.wps.com/document/healthcare/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/muc1-targeting-small-peptide-radiopharmaceuticals-for-breast-cancer/354158/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":99,"encodingFormat":97,"isAccessibleForFree":100,"interactionStatistic":101},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/muc1-targeting-small-peptide-radiopharmaceuticals-for-breast-cancer/354158.png","ImageObject",300,407,{"name":92,"@type":93},"Nguyễn Văn Học","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-10-23","2026-09-22",true,{"@type":102,"interactionType":103,"userInteractionCount":29},"InteractionCounter",{"@type":104},"ViewAction",{"@type":106,"mainEntity":107},"FAQPage",[108,114,118],{"name":109,"@type":110,"acceptedAnswer":111},"Why target MUC1 in breast cancer?","Question",{"text":112,"@type":113},"MUC1 is overexpressed and underglycosylated in many epithelial cancers, which exposes a core VNTR peptide region relevant for targeting.","Answer",{"name":115,"@type":110,"acceptedAnswer":116},"Which minimal VNTR epitope sequences were tested?",{"text":117,"@type":113},"The study explored three minimal epitope sequences from the VNTR: RPAPGS, PPAHGVT, and PDTRP.",{"name":119,"@type":110,"acceptedAnswer":120},"Did the peptides bind specifically to MUC1?",{"text":121,"@type":113},"No. Cell uptake was low, MUC1-expressing and MUC1-knockout cells showed no specificity, binding affinity could not be reliably determined, and surface plasmon resonance confirmed absent binding for tested labeled peptides.","https://schema.org",{"og:url":83,"og:type":124,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":126,"canonical":83},"index,follow",{"doc_id":128,"site_id":62},354158,1790810602,{"code":4,"msg":5,"data":131},{"doc_id":128,"user_id":132,"nickname":92,"user_avatar":133,"doc_module":4,"category_id":34,"category_name":35,"doc_title":65,"doc_description":67,"doc_content":134,"file_id":135,"file_url":136,"file_type":137,"file_size":138,"view_count":29,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":139,"language":140,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":141,"faqs":142,"seo_title":143,"seo_description":67,"update_tm":144,"read_time":41},1374402739827,"https://ap-avatar.wpscdn.com/avatar/14000c97e7351f1a627?x-image-process=image/resize,m_fixed,w_180,h_180&k=1787885694763230660","Malek etal. EJNMMI Radiopharmacy and Chemistry (2026) 11:33  \n[https://doi.org/10.1186/s41181-026-00451-1](https://doi.org/10.1186/s41181-026-00451-1)  \nEJNMMI Radiopharmacy and Chemistry  \nRESEARCH ARTICLE Open Access  \nMUC1-targeting small peptide  \nradiopharmaceuticals for breast cancer  \nRim Malek1, Madeleine Landry1, Pierre Cheung1 and Corinne Beinat1*  \n*Correspondence:  \nCorinne Beinat[cbeinat@stanford.edu](cbeinat@stanford.edu)[ ](cbeinat@stanford.edu)1Department of Radiology, Molecular Imaging Program at Stanford, Stanford University, 1701 Page Mill Road, Stanford, CA 94305, USA  \nAbstract  \nBackground Mucin 1 (MUC1) is a transmembrane glycoprotein overexpressed and underglycosylated in numerous epithelial cancers, including breast cancer. Reduced glycosylation leads to the exposure of the variable number tandem repeat (VNTR) region. To the best of our knowledge, all peptides previously described in the literature target the same epitope sequence of the VNTR. Given the high prevalence of breast cancer and the limited treatment options for the aggressive subtype triple-negative breast cancer (TNBC), due to its lack of oestrogen receptors (ER), progesterone receptors (PR), and human epidermal growth factor receptor 2 (HER2), we sought to develop a small peptide radiopharmaceutical targeting MUC1 by exploring all  \n3 minimal epitope sequences ofthe VNTR: RPAPGS, PPAHGVT and PDTRP. We also investigated the influence of linker lipophilicity on the binding affinity to MUC1 . Results The reference compound 1 showed the highest cell uptake among all tested compounds. While some statistically significant differences were observed for the cell uptake between the different peptide sequences and the linkers, the uptake was so low that no reliable structure-activity relationships could be established. We then studied the specificity of all compounds for MUC1 by comparing the uptake in MUC1-expressing and MUC1-knockout (KO) cells, and unexpectedly observed no specificity for any compound. A saturation binding assay of several peptides showed their binding was too low to reliably determine their binding affinity (Kd) . Surface plasmon resonance (SPR) further confirmed the absence of binding of all [NatGa] -and [Nat Lu]-labelled peptides tested. Given the discrepancies between our cell data and the previously reported results, we next assessed the specificity of the reference (1) in vivo in mice bearing MUC1-expressing and MUC1-knockdown (KD) tumours, which further proved its non-specificity.  \nConclusions While MUC1 is a very promising target for the development of breast cancer theranostics, designing peptidomimetics based on its minimal epitopes do not lead to high-affinity binders. Our ongoing efforts involve utilizing phage-display to identify new peptide sequences.  \nKeywords MUC1, Radiopharmaceutical, Epithelial cancer, Breast cancer, Triplenegative breast cancer  \n© The Author(s) 2026. Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit [http://creativecommons.org/l](http://creativecommons.org/l)icenses/by-nc-nd/4.0/.  \nMal","cbCaipficN9rCJaZ","https://ap.wps.com/l/cbCaipficN9rCJaZ","pdf",1579915,12,"English","# Abstract\n## Background\n## Results\n## Conclusions\n## Keywords\n## Background","[{\"question\":\"Why target MUC1 in breast cancer?\",\"answer\":\"MUC1 is overexpressed and underglycosylated in many epithelial cancers, which exposes a core VNTR peptide region relevant for targeting.\"},{\"question\":\"Which minimal VNTR epitope sequences were tested?\",\"answer\":\"The study explored three minimal epitope sequences from the VNTR: RPAPGS, PPAHGVT, and PDTRP.\"},{\"question\":\"Did the peptides bind specifically to MUC1?\",\"answer\":\"No. Cell uptake was low, MUC1-expressing and MUC1-knockout cells showed no specificity, binding affinity could not be reliably determined, and surface plasmon resonance confirmed absent binding for tested labeled peptides.\"}]","MUC1-targeting small peptide radiopharmaceuticals for breast cancer | PDF",1790109288]