%0 Journal Article %T Differential expression of HIF-1¦Á in CD44+CD24-/low breast ductal carcinomas %A Jo£¿o Oliveira-Costa %A Juliana S Zanetti %A Gi¨®rgia G Silveira %A Danilo F Soave %A Lucinei R Oliveira %A Ver£¿nica A Zorgetto %A Fernando A Soares %A S¨¦rgio Zucoloto %A Alfredo Ribeiro-Silva %J Diagnostic Pathology %D 2011 %I BioMed Central %R 10.1186/1746-1596-6-73 %X Immunohistochemical analysis of CD44+CD24-/low expression and its relationship with hypoxia markers and clinical outcome were evaluated in 253 samples of breast ductal carcinomas. Double-immunolabeling was performed using EnVision Doublestain System (Dako, Carpinteria, CA, USA). Slides were then scanned into high-resolution images using Aperio ScanScope XT and then, visualized in the software Image Scope (Aperio, Vista, CA, USA).In univariate analysis, CD44+CD24-/low expression showed association with death due to breast cancer (p = 0.035). Breast tumors expressing CD44+CD24-/low immunophenotype showed relationship with HIF-1¦Á (p = 0.039) and negativity for HER-2 (p = 0.013).Considering that there are strong evidences that the fraction of a tumour considered to be cancer stem cells is plastic depending upon microenvironmental signals, our findings provide further evidence that hypoxia might be related to the worse prognosis found in CD44+CD24-/low positive breast tumors.The cancer stem cell (CSC) hypothesis postulates that tumors are maintained by a self-renewing CSC population that is also capable of differentiating into non-self-renewing cell populations that constitute the bulk of the tumor [1]. The first insight indicating a role of breast cancer stem cells (BCSC) in breast carcinogenesis was demonstrated by the study of Al-Hajj and co-workers, where Lin-CD44+CD24-/low cells injected into the mammary fat pad of non-obese diabetic/severed combined immunodeficient (NOD/SCID) mice were able to form palpable tumors, even with just a few hundred of cells being transplanted. Another interesting observation in the same study was the fact that Lin-CD44+CD24-/low cells were not only able to give origin to additional Lin-CD44+CD24-/low cells, but also generated phenotypically distinct cells, indicating that BCSC could generate an homogeneous population of non-tumorigenic cells, besides the generation of new BCSC [2].Stem cells renewal and differentiation can be directly i %K breast cancer %K CD44 %K CD24 %K HIF-1¦Á %K hypoxia %K immunohistochemistry %K prognosis %K stem cell %U http://www.diagnosticpathology.org/content/6/1/73