title: Erythropoietin-mediated activation of JAK-STAT signaling contributes to cellular invasion in head and neck squamous cell carcinoma.
abstract: Originally characterized as a growth factor for erythrocytes, erythropoietin (EPO) is used to treat anemia and fatigue in cancer patients receiving radiation therapy and chemotherapy. EPO and the EPO receptor (EPOR) are expressed in nonhematopoietic cells and cancers. However, the role of EPO and EPOR within nonhematopoietic cancer cells remains incompletely understood. Although a recent clinical trial demonstrated worse tumor control and survival in head and neck cancer patients treated with EPO, the role of EPO and EPOR in head and neck squamous cell carcinoma (HNSCC) has not been examined. In the present study, we demonstrate the previously unrecognized EPO-mediated invasion by HNSCC cells through the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling pathway. Furthermore, we confirmed the expression of EPO and EPOR in a panel of human HNSCC cell lines and tissue specimens. Pharmacological doses of EPO also had a limited proliferation effect in these cell lines. These results define a novel role for EPO in mediating tumor cell invasion. Increased levels of EPO and EPOR in lymph node metastases as compared to primary tumors from HNSCC patients further support the role of EPO/EPOR in HNSCC disease progression and metastasis.
authors.affiliation: Department of Otolaryngology--Head and Neck Surgery, The Eye & Ear Institute, University of Pittsburgh Cancer Institute, Pittsburgh, PA 15213, USA. laisy@upmc.edu
authors.forename: Stephen Y
authors.initials: SY
authors.lastname: Lai
authors.forename: Erin E
authors.initials: EE
authors.lastname: Childs
authors.forename: Sichuan
authors.initials: S
authors.lastname: Xi
authors.forename: Francesca M
authors.initials: FM
authors.lastname: Coppelli
authors.forename: William E
authors.initials: WE
authors.lastname: Gooding
authors.forename: Alan
authors.initials: A
authors.lastname: Wells
authors.forename: Robert L
authors.initials: RL
authors.lastname: Ferris
authors.forename: Jennifer R
authors.initials: JR
authors.lastname: Grandis
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000473:pathology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004789:Enzyme Activation / Q000187:drug effects; D004921:Erythropoietin / Q000378:metabolism / Q000494:pharmacology*; D005260:Female; D006258:Head and Neck Neoplasms / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D053614:Janus Kinase 2; D008297:Male; D008875:Middle Aged; D008894:Milk Proteins / Q000235:genetics / Q000378:metabolism*; D009154:Mutation / Q000235:genetics; D009361:Neoplasm Invasiveness; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D017467:Receptors, Erythropoietin / Q000378:metabolism; D050799:STAT5 Transcription Factor; D015398:Signal Transduction / Q000187:drug effects*; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*; D020032:Tyrphostins / Q000494:pharmacology
chemical_list: D004268:DNA-Binding Proteins; D008894:Milk Proteins; D047428:Protein Kinase Inhibitors; D011518:Proto-Oncogene Proteins; D017467:Receptors, Erythropoietin; D050799:STAT5 Transcription Factor; D015534:Trans-Activators; D020032:Tyrphostins; C095512:alpha-cyano-(3,4-dihydroxy)-N-benzylcinnamide; D004921:Erythropoietin; D011505:Protein-Tyrosine Kinases; C507924:JAK2 protein, human; D053614:Janus Kinase 2