Breast cancer stem cells (BCSC) have been identified in breast carcinoma as CD44(+)/CD24(-/low) cells, which display tumorigenic activity and have the ability to self-renew, differentiate and metastasize.
In MCF10DCIS cells treated with vitamin D compounds (1α25(OH)2D3 or BXL0124), the breast cancer stem cell-like population, identified by the CD44(+)/CD24(-/low) and CD49f(+)/CD24(-/low) subpopulations, was reduced.
Our results suggest that CD24 overexpression is an independent unfavourable prognostic factor in breast cancer, especially for luminal A and TNBC subtypes, and CD24 may be a promising therapeutic target for specific subtypes of breast cancer.
Furthermore, the expression of SMO and Gli1 was positively correlated with the expression of CD44+ / CD24-, and the expression of SMO and Gli1 in CD44+ / CD24- tissues was associated with a significantly shorter OS (overall survival) and DFS (disease-free survival) in breast cancer patients receiving chemotherapy.
Second, we overlap all the intrinsic subtypes across cHER2+ BC to obtain a continuum of mixed phenotypes in which one extreme exhibits a high identity with ALDH+ CSCs and the other extreme exhibits a high preponderance of CD44+CD24-/low CSCs.
Knockdown of CD24 expression by CD24-siRNA significantly inhibited invasion and cell viability, and induced apoptosis and increased sensitivity of MCF-7 cells to TAM, indicating that knockdown of CD24 by siRNA might be a potential therapeutic approach against human breast cancer.
Cytoplasmic YB1 was detected more often in carcinomas of ductal type (p = 0.002), of higher nuclear grade (p < 0.001), with lack of ER expression (p = 0.002), positive expression of p53 and Ki67 (p = 0.002 and p = 022, respectively), and with present CD44(+)/CD24(-/low) breast cancer stem cells (p = 0.001), while its association with bcl-2 was found to be inverse (p = 0.042).
Investigations in endocrine-resistant breast cancer cell lines and SRC-1(-/-)/PyMT mice confirmed a role for SRC-1 and HOXC11 in downregulation of CD24 and PAWR.
MKP1 overexpression was also detected in irradiated HER2-positive breast cancer stem-like cells (HER2(+)/CD44(+)/CD24(-/low)) isolated from a radioresistant breast cancer cell population after long-term radiation treatment.
Knockdown of CD24 in breast cancer cells positive for endogenous HER2 downregulated HER2 expression, whereas knockdown of HER2 did not affect the expression of CD24.
Single-nucleotide polymorphisms (SNPs) of CD24 were genotyped by the Sequenom MassArray iPLEX Gold System in 170 patients with breast cancer, and a total of 120 patients with histologically confirmed T2-4N0-2 M0 breast cancer were recruited to therapy with docetaxel, doxorubicin, and cyclophosphamide (TAC) as neoadjuvant chemotherapy.
Interestingly, a protective role of the CD24rs3838646 polymorphism was found in the risk of breast cancer, but lack of statistical significance (del allele vs. TG allele: OR = 0.89; 95 % CI, 0.79-1.01; P OR = 0.063; del/del vs.
CD24(-/low) stem-like breast cancer marker defines the radiation-resistant cells involved in memorization and transmission of radiation-induced genomic instability.
CD44⁻CD24⁺ CSCs-like displayed a distinct bone tropism signature that was enriched in genes that discriminate bone metastases of breast cancer from metastases at other organs.
The CD44(+)/CD24(-/low) and ALDH1+ phenotypes were identified in 16% and 15% of the familial breast cancer cases, respectively, and associated with high-tumor grade, a high-mitotic count, and component features of the medullary type of breast cancer.
Lastly, we used FVBN202 transgenic mouse model of breast carcinoma and determined the hormone receptor status, the proportion of CD44(+)/CD24(-/low) breast cancer stem-like cells, and the behavior of the tumor.
The systematic determination of SLUG/SNAIL2 as a stem/CD44+CD24(-/low) cell-associated protein may improve the therapeutic management of HER2+ breast carcinomas.
CD24Ala57Val polymorphism predicts pathologic complete response to sequential anthracycline- and taxane-based neoadjuvant chemotherapy for primary breast cancer.