PMID- 28377489 OWN - NLM STAT- MEDLINE DCOM- 20180328 LR - 20200930 IS - 1538-8514 (Electronic) IS - 1535-7163 (Linking) VI - 16 IP - 7 DP - 2017 Jul TI - Preclinical Activity of the Novel Anti-Prolactin Receptor (PRLR) Antibody-Drug Conjugate REGN2878-DM1 in PRLR-Positive Breast Cancers. PG - 1299-1311 LID - 10.1158/1535-7163.MCT-16-0839 [doi] AB - The Prolactin Receptor (PRLR) is a type 1 cytokine receptor that is expressed in a subset of breast cancers and may contribute to its pathogenesis. It is relatively overexpressed in approximately 25% of human breast tumors while expressed at low levels in some normal human tissues including the mammary gland. We developed an anti-PRLR antibody-drug conjugate (ADC), to target PRLR-positive breast cancer. REGN2878-DM1 is comprised of a fully human high-affinity function-blocking anti-PRLR IgG1 antibody (REGN2878) conjugated via a noncleavable SMCC linker to the cytotoxic maytansine derivative DM1. Both unconjugated REGN2878 and conjugated REGN2878-DM1 block PRL-mediated activation in vitro and are rapidly internalized into lysosomes. REGN2878-DM1 induces potent cell-cycle arrest and cytotoxicity in PRLR-expressing tumor cell lines. In vivo, REGN2878-DM1 demonstrated significant antigen-specific antitumor activity against breast cancer xenograft models. In addition, REGN2878-DM1 showed additive activity when combined with the antiestrogen agent fulvestrant. These results illustrate promising antitumor activity against PRLR-positive breast cancer xenografts and support the evaluation of anti-PRLR ADCs as potential therapeutic agents in breast cancer. Mol Cancer Ther; 16(7); 1299-311. (c)2017 AACR. CI - (c)2017 American Association for Cancer Research. FAU - Kelly, Marcus P AU - Kelly MP AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. marcus.kelly@regeneron.com. FAU - Hickey, Carlos AU - Hickey C AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. FAU - Makonnen, Sosina AU - Makonnen S AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. FAU - Coetzee, Sandra AU - Coetzee S AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. FAU - Jalal, Sumreen AU - Jalal S AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. FAU - Wang, Yu AU - Wang Y AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. FAU - Delfino, Frank AU - Delfino F AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. FAU - Shan, Jing AU - Shan J AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. FAU - Potocky, Terra B AU - Potocky TB AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. FAU - Chatterjee, Ishita AU - Chatterjee I AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. FAU - Andreev, Julian AU - Andreev J AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. FAU - Kunz, Arthur AU - Kunz A AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. FAU - D'Souza, Christopher AU - D'Souza C AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. FAU - Giurleo, Jason T AU - Giurleo JT AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. FAU - Nittoli, Thomas AU - Nittoli T AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. FAU - Trail, Pamela A AU - Trail PA AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. FAU - Thurston, Gavin AU - Thurston G AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. FAU - Kirshner, Jessica R AU - Kirshner JR AD - Regeneron Pharmaceuticals, Inc., Tarrytown, New York. LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't DEP - 20170404 PL - United States TA - Mol Cancer Ther JT - Molecular cancer therapeutics JID - 101132535 RN - 0 (Antibodies, Anti-Idiotypic) RN - 0 (Antibodies, Monoclonal, Humanized) RN - 0 (Immunoconjugates) RN - 0 (Receptors, Prolactin) SB - IM MH - Animals MH - Antibodies, Anti-Idiotypic/administration & dosage/immunology MH - Antibodies, Monoclonal, Humanized/*administration & dosage/immunology MH - Breast Neoplasms/*drug therapy/genetics/immunology/pathology MH - Cell Proliferation/drug effects MH - Female MH - Humans MH - Immunoconjugates/*administration & dosage/immunology MH - Mice MH - Receptors, Prolactin/genetics/*immunology MH - Xenograft Model Antitumor Assays EDAT- 2017/04/06 06:00 MHDA- 2018/03/29 06:00 CRDT- 2017/04/06 06:00 PHST- 2016/12/06 00:00 [received] PHST- 2017/03/21 00:00 [revised] PHST- 2017/03/29 00:00 [accepted] PHST- 2017/04/06 06:00 [pubmed] PHST- 2018/03/29 06:00 [medline] PHST- 2017/04/06 06:00 [entrez] AID - 1535-7163.MCT-16-0839 [pii] AID - 10.1158/1535-7163.MCT-16-0839 [doi] PST - ppublish SO - Mol Cancer Ther. 2017 Jul;16(7):1299-1311. doi: 10.1158/1535-7163.MCT-16-0839. Epub 2017 Apr 4.