Characteristics Of CD44⁺CD24^-/low Phenotype Cells In Breast Cancer

Objects: The aim of this study was to isolate the CD44⁺CD24^-/low phenotype cells in MCF-7 and T47D cell lines and investigate their features of cell cycles and proliferations. To identify the specificity of CD44⁺CD24^-/low marker to breast cancer cells by using the marker separate the subpopulation in others cell lines. To know whether neoadjuvant chemotherapy has the ability to arise the percentage of CD44⁺CD24^-/low phenotype cells in breast cancer.Methods: The CD44⁺CD24^-/low subpopulation was separated from MCF-7 and T47D cell lines by flow cytometry. Identify the difference in cell cycles between the CD44⁺CD24^-/low subpopulation and non- CD44⁺CD24^-/low subpopulation. Using the BrdU flow cytometry kit to detect the proliferation of the CD44⁺CD24^-/low subpopulation can identify whether such subpopulation has the same feature as breast cancer stem cells.We inspected the proportion and cell cycle of CD44⁺CD24^-/low subpopulation in LTEP-2, SKVO3 and HT1080 cell lines to detect the CD44⁺CD24^-/low specific expression besides breast cancer cells.We selected the breast cancer specimens with neoadjuvant chemotherapy and no chemotherapy to contrast the percentage of CD44⁺CD24^-/low subpopulation in two teams.Results: The CD44⁺CD24^-/low phenotype cells was be separated from the MCF-7 and T47D cell lines successfully. The CD44⁺CD24^-/low phenotype cells contained a higher percentage of G0/G1 phase cells (P=0.005) and a lower percentage of S phase cells(P<0.05). The CD44⁺CD24^-/low phenotype cells with BrdU+ account for 24.2±7.3 (%) in MCF-7 and 13.7±4.2 (%) in T47D. All The BrdU+ cells in these two cell lines were tagged with CD44⁺CD24^-/low marker.The marker of CD44⁺CD24^-/low was not only specify for breast cancer cells be proved and separated the CD44⁺CD24^-/low phenotype cells from 3 deferent cell lines (LTEP-2, SKVO3 and HT1080) besides breast caner successfully.The specimens of neoadjuvant chemotherapy team contained a much higher percentage of CD44⁺CD24^-/low phenotype cells than control team (P＜0.05). Conclusion: The CD44⁺CD24^-/low phenotype cells has the similar characteristics as cancer stem cells in aspect of cell cycles and proliferation. The marker of CD44⁺CD24^-/low was not only specify for breast cancer cells. The percentage of CD44⁺CD24^-/low subpopulation can be raised up by neoadjuvant chemotherapy.