title: Zinc isotopic compositions of breast cancer tissue.
abstract: An early diagnostic biomarker for breast cancer is essential to improve outcome. High precision isotopic analysis, originating in Earth sciences, can detect very small shifts in metal pathways. For the first time, the natural intrinsic Zn isotopic compositions of various tissues in breast cancer patients and controls were determined. Breast cancer tumours were found to have a significantly lighter Zn isotopic composition than the blood, serum and healthy breast tissue in both groups. The Zn isotopic lightness in tumours suggests that sulphur rich metallothionein dominates the isotopic selectivity of a breast tissue cell, rather than Zn-specific proteins. This reveals a possible mechanism of Zn delivery to Zn-sequestering vesicles by metallothionein, and is supported by a similar signature observed in the copper isotopic compositions of one breast cancer patient. This change in intrinsic isotopic compositions due to cancer has the potential to provide a novel early biomarker for breast cancer.
authors.affiliation: Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, OX1 3AN, UK. fiona.larner@earth.ox.ac.uk.
authors.forename: Fiona
authors.initials: F
authors.lastname: Larner
authors.forename: Laura N
authors.initials: LN
authors.lastname: Woodley
authors.forename: Sami
authors.initials: S
authors.lastname: Shousha
authors.forename: Ashley
authors.initials: A
authors.lastname: Moyes
authors.forename: Emma
authors.initials: E
authors.lastname: Humphreys-Williams
authors.forename: Stanislav
authors.initials: S
authors.lastname: Strekopytov
authors.forename: Alex N
authors.initials: AN
authors.lastname: Halliday
authors.forename: Mark
authors.initials: M
authors.lastname: Rehkämper
authors.forename: R Charles
authors.initials: RC
authors.lastname: Coombes
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis* / Q000097:blood / Q000378:metabolism; D001940:Breast / Q000737:chemistry / Q000378:metabolism; D001943:Breast Neoplasms / Q000737:chemistry* / Q000378:metabolism; D003300:Copper / Q000032:analysis* / Q000097:blood / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D015033:Zinc Isotopes / Q000032:analysis* / Q000097:blood / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D015033:Zinc Isotopes; D003300:Copper