Case Study: Heterogeneity of and CD44+/CD24-Cancer Stem Cell Subpopulation of Breast Cancer Patients in Bandung, Indonesia

Breast cancer (BC) cells characteristics have played a crucial role in clinical strategies decision-making and patient outcome prediction. Although there have been several studies examining this, there are still relatively few that analyze stem cell subpopulations or protein biomarkers. The conducted research sought to elucidate breast cancer subtype characteristics based on immunohistochemical analysis and cancer stem cell presence based on flow cytometry analysis in three breast cancer samples from Bandung, Indonesia. A flow cytometry analysis was conducted to determine how much CD44/CD24 was expressed as a marker of cancer stem cell in isolated BC cells using various cell references, such as cell lines of SKBR-3, MDA-MB-468, and Hs587T. Immunohistochemistry analysis was carried out to investigate the expression of p53, HER2, PGR, Ki67, and ER in sample tissue sections. According to histological analysis, 2 samples were solid mammary carcinoma, and 1 sample was mammary fibroadenoma. Immunohistochemistry and histological analysis showed that all BC tissues are classified as Luminal B. In addition, a large percentage of CD44+/CD24-subpopulation was found in isolated BC cells (> 90 % in patients 1 and 3; > 60 % in patient 2). All samples showed similarity to Hs587T cell line characteristic. This study has successfully characterized solid mammary tumors and mammary fibroadenoma with luminal B characteristics. All specimens contained a high proportion of cancer stem cells.