PMID- 25964777 OWN - NLM STAT- PubMed-not-MEDLINE DCOM- 20150512 LR - 20181113 IS - 1664-2392 (Print) IS - 1664-2392 (Electronic) IS - 1664-2392 (Linking) VI - 6 DP - 2015 TI - Role of IGF1R in Breast Cancer Subtypes, Stemness, and Lineage Differentiation. PG - 59 LID - 10.3389/fendo.2015.00059 [doi] LID - 59 AB - Insulin-like growth factor (IGF) signaling is fundamental for growth and survival. A large body of evidence (laboratory, epidemiological, and clinical) implicates the exploitation of this pathway in cancer. Up to 50% of breast tumors express the activated form of the type 1 insulin-like growth factor receptor (IGF1R). Breast cancers are categorized into subtypes based upon hormone and ERRB2 receptor expression and/or gene expression profiling. Even though IGF1R influences tumorigenic phenotypes and drug resistance across all breast cancer subtypes, it has specific expression and function in each. In some subtypes, IGF1R levels correlate with a favorable prognosis, while in others it is associated with recurrence and poor prognosis, suggesting different actions based upon cellular and molecular contexts. In this review, we examine IGF1R expression and function as it relates to breast cancer subtype and therapy-acquired resistance. Additionally, we discuss the role of IGF1R in stem cell maintenance and lineage differentiation and how these cell fate influences may alter the differentiation potential and cellular composition of breast tumors. FAU - Farabaugh, Susan M AU - Farabaugh SM AD - Department of Pharmacology and Chemical Biology, University of Pittsburgh , Pittsburgh, PA , USA ; Women's Cancer Research Center, Magee-Womens Research Institute, University of Pittsburgh Cancer Institute, University of Pittsburgh , Pittsburgh, PA , USA. FAU - Boone, David N AU - Boone DN AD - Department of Pharmacology and Chemical Biology, University of Pittsburgh , Pittsburgh, PA , USA ; Women's Cancer Research Center, Magee-Womens Research Institute, University of Pittsburgh Cancer Institute, University of Pittsburgh , Pittsburgh, PA , USA. FAU - Lee, Adrian V AU - Lee AV AD - Department of Pharmacology and Chemical Biology, University of Pittsburgh , Pittsburgh, PA , USA ; Women's Cancer Research Center, Magee-Womens Research Institute, University of Pittsburgh Cancer Institute, University of Pittsburgh , Pittsburgh, PA , USA ; Department of Human Genetics, University of Pittsburgh , Pittsburgh, PA , USA. LA - eng GR - R01 CA094118/CA/NCI NIH HHS/United States PT - Journal Article PT - Review DEP - 20150424 PL - Switzerland TA - Front Endocrinol (Lausanne) JT - Frontiers in endocrinology JID - 101555782 PMC - PMC4408912 OTO - NOTNLM OT - ER+ OT - ERBB2+ OT - IGF1R OT - breast cancer subtypes OT - lineages OT - luminal OT - triple negative EDAT- 2015/05/13 06:00 MHDA- 2015/05/13 06:01 PMCR- 2015/01/01 CRDT- 2015/05/13 06:00 PHST- 2015/02/15 00:00 [received] PHST- 2015/04/07 00:00 [accepted] PHST- 2015/05/13 06:00 [entrez] PHST- 2015/05/13 06:00 [pubmed] PHST- 2015/05/13 06:01 [medline] PHST- 2015/01/01 00:00 [pmc-release] AID - 10.3389/fendo.2015.00059 [doi] PST - epublish SO - Front Endocrinol (Lausanne). 2015 Apr 24;6:59. doi: 10.3389/fendo.2015.00059. eCollection 2015.