Neuroendocrine markers are expressed in human mammary glands.
BACKGROUND
Regulatory peptides have previously been detected in epithelial cells of human mammary glands. As these peptides are produced by scattered neuroendocrine cells in the epithelium of other tissues the aim of this study was to investigate whether the mammary glands express molecular markers for neuroendocrine cells.


METHODS
Specimens from 28 human mammary glands were retrieved. The distribution of immunoreactive cells was determined using immunohistochemistry with antibodies versus a set of endocrine markers including peptide hormones, chromogranins/secretogranins, vesicular monoamine transporters, synaptophysin, serotonin and synaptic vesicle protein 2.


RESULTS
Cells of the luminal epithelium of ducts and lobules of human mammary glands expressed vesicular monoamine transporter 2 and chromogranin B, as well as the previously reported regulatory peptides obestatin, ghrelin, adrenomedullin and apelin. Using consecutive sections, it was revealed that the immunoreactivity patterns of the regulatory peptides and vesicular monoamine transporter 2 were similar. Interestingly, immunoreactivity for secretogranin II, secretogranin III and chromogranin B was identified in myoepithelial cells. No immunoreactivity was detected for chromogranin A or synaptophysin.


CONCLUSIONS
Specific cells in the epithelium and myoepithelium of mammary glands express neuroendocrine markers suggesting that mammary glands may have neuroendocrine functions.
Grönberg
Malin
M
Dept. of Medical Sciences, Section of Endocrine Oncology, Uppsala University, SE-751 85 Uppsala, Sweden. malin.gronberg@medsci.uu.se
Amini
Rose-Marie
RM
Stridsberg
Mats
M
Janson
Eva T
ET
Saras
Jan
J
D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000032:analysis*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D042361:Mammary Glands, Human / Q000378:metabolism*; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D055099:Neuroendocrine Cells / Q000378:metabolism; D036361:Peptide Hormones / Q000378:metabolism; D055815:Young Adult
D015415:Biomarkers; D009419:Nerve Tissue Proteins; D036361:Peptide Hormones