title: Increased tumor cell expression of Axl is a marker of aggressive features in breast cancer among African women.
abstract: Axl, a receptor tyrosine kinase belonging to the Tyro/Axl/Mer (TAM) family, has been shown to be overexpressed in breast cancer with poor outcome. Moreover, Axl was associated with a basal-like phenotype (BLP) in these tumors. Our aim was to investigate Axl expression in breast cancers from an African population since these tumors are known to be aggressive and have a high frequency of the basal-like phenotype. We studied 170 paraffin-embedded breast carcinoma cases by tissue microarrays and immunohistochemical methods. In total, 128 tumor cases (75%) had strong Axl expression and 42 cases (25%) had weak or negative staining. Strong expression of Axl was associated with high tumor grade (p < 0.0005), estrogen receptor (ER) negativity (p = 0.024), p53 expression (p = 0.004), P-cadherin positivity (p = 0.017), and basal-like phenotypic profiles BLP2 (p = 0.033) and BLP3 (p = 0.022). In addition, Axl overexpression also showed an association with markers of tumor cell proliferation and tumor angiogenesis. In conclusion, our findings indicate strong expression of Axl in a high proportion of breast cancer cases among African women and associations with markers of aggressive features, indicating poor prognosis. These findings suggest Axl as a potential therapeutic target in this population.
authors.affiliation: Centre for Cancer Biomarkers CCBIO, Department of Clinical Medicine, University of Bergen, Bergen, Norway.|BerGenBio AS, Bergen, Norway.
authors.forename: Lavina
authors.initials: L
authors.lastname: Ahmed
authors.affiliation: Centre for Cancer Biomarkers CCBIO, Department of Clinical Medicine, University of Bergen, Bergen, Norway.
authors.forename: Hawa
authors.initials: H
authors.lastname: Nalwoga
authors.affiliation: Department of Pathology, Haukeland University Hospital, Bergen, Norway.
authors.forename: Jarle B
authors.initials: JB
authors.lastname: Arnes
authors.affiliation: Department of Pathology, Makerere University College of Health Sciences, Kampala, Uganda.
authors.forename: Henry
authors.initials: H
authors.lastname: Wabinga
authors.affiliation: BerGenBio AS, Bergen, Norway.
authors.forename: David R
authors.initials: DR
authors.lastname: Micklem
authors.affiliation: Centre for Cancer Biomarkers CCBIO, Department of Clinical Medicine, University of Bergen, Bergen, Norway.|Department of Pathology, Haukeland University Hospital, Bergen, Norway.
authors.forename: Lars A
authors.initials: LA
authors.lastname: Akslen
mesh_terms: D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D044383:Black People / Q000235:genetics; D001943:Breast Neoplasms / Q000175:diagnosis*; D015820:Cadherins / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D005260:Female; D006801:Humans; D008875:Middle Aged; D009389:Neovascularization, Pathologic; D011379:Prognosis; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000235:genetics / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism; D000094963:Axl Receptor Tyrosine Kinase
chemical_list: D014408:Biomarkers, Tumor; D015820:Cadherins; D011518:Proto-Oncogene Proteins; D011960:Receptors, Estrogen; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; D020794:Receptor Protein-Tyrosine Kinases; D000094963:Axl Receptor Tyrosine Kinase; C000722289:AXL protein, human
keywords: Axl; Basal-like breast cancer; angiogenesis