Themajorityofbreastcancersoriginateinthelobularorductalcellsofthemilk-producingglands.Inthesestructures,therearetwomaincelltypes:theinnerluminalcellssurroundedbybasalmyoepithelium.Thesecellstypesaredistinctandaretheprecursorstovariousformsofbreastcancer.Assuch,itisimportanttostudythesecellpopulationsindependentlyaswellasinco-culturemodelssystems.Zenbioisproudtooffercryopreseveredhumanmammaryepithelialcells.
CellshavetestednegativeforHIV-1,HIV-2,HTLV-1,HTLV-2,HbsAG,HbcAB,HCV,andRPR.
Basalmyoepithelialcellsurroundtheluminalcellsandhavebothcontractilemuscleandepithelialproperties.Basalmyoepithelialcellstendtodominatenormalprimarycultures.Additionally,basal-typebreastcancersaretypicallyestrogenandprogesteronereceptornegative.
Luminalcellslinetheapicalsurfaceofthenormalbreastductandhavesecretoryproperties.MostbreastcancersarisefromluminalcellsandareheterogeneousintheirexpressionofhormonereceptorsandERBB2expression.