PMID- 34208071 OWN - NLM STAT- PubMed-not-MEDLINE LR - 20230920 IS - 2072-6694 (Print) IS - 2072-6694 (Electronic) IS - 2072-6694 (Linking) VI - 13 IP - 12 DP - 2021 Jun 11 TI - Targeting mTOR and Glycolysis in HER2-Positive Breast Cancer. LID - 10.3390/cancers13122922 [doi] LID - 2922 AB - Up to one third of all breast cancers are classified as the aggressive HER2-positive subtype, which is associated with a higher risk of recurrence compared to HER2-negative breast cancers. The HER2 hyperactivity associated with this subtype drives tumor growth by up-regulation of mechanistic target of rapamycin (mTOR) pathway activity and a metabolic shift to glycolysis. Although inhibitors targeting the HER2 receptor have been successful in treating HER2-positive breast cancer, anti-HER2 therapy is associated with a high risk of recurrence and drug resistance due to stimulation of the PI3K-Akt-mTOR signaling pathway and glycolysis. Combination therapies against HER2 with inhibition of mTOR improve clinical outcomes compared to HER2 inhibition alone. Here, we review the role of the HER2 receptor, mTOR pathway, and glycolysis in HER2-positive breast cancer, along with signaling mechanisms and the efficacy of treatment strategies of HER2-positive breast cancer. FAU - Holloway, Ryan W AU - Holloway RW AUID- ORCID: 0000-0002-9475-0130 AD - Department of Biochemistry & Molecular Biology, Faculty of Medicine, Dalhousie University, Halifax, NS B3H 4R2, Canada. FAU - Marignani, Paola A AU - Marignani PA AUID- ORCID: 0000-0001-8070-905X AD - Department of Biochemistry & Molecular Biology, Faculty of Medicine, Dalhousie University, Halifax, NS B3H 4R2, Canada. LA - eng GR - 0/Dalhousie Medical Research Foundation/ GR - 0/Breast Cancer Society of Canada/ PT - Journal Article PT - Review DEP - 20210611 PL - Switzerland TA - Cancers (Basel) JT - Cancers JID - 101526829 PMC - PMC8230691 OTO - NOTNLM OT - 2-deoxyglucose OT - HER2-positive breast cancer OT - Herceptin OT - LKB1 OT - PI3K-Akt-mTOR signaling pathway OT - clinical diagnostics OT - glycolysis OT - mTOR OT - rapalog OT - trastuzumab OT - tumor recurrence COIS- The authors declare no conflict of interest. EDAT- 2021/07/03 06:00 MHDA- 2021/07/03 06:01 PMCR- 2021/06/11 CRDT- 2021/07/02 01:33 PHST- 2021/05/10 00:00 [received] PHST- 2021/06/09 00:00 [revised] PHST- 2021/06/10 00:00 [accepted] PHST- 2021/07/02 01:33 [entrez] PHST- 2021/07/03 06:00 [pubmed] PHST- 2021/07/03 06:01 [medline] PHST- 2021/06/11 00:00 [pmc-release] AID - cancers13122922 [pii] AID - cancers-13-02922 [pii] AID - 10.3390/cancers13122922 [doi] PST - epublish SO - Cancers (Basel). 2021 Jun 11;13(12):2922. doi: 10.3390/cancers13122922.