In the field of cancer biology, elucidating the factors that promote cancer cellinvasion and progression is crucial for the identification of novel therapeutictargets. CD44 has emerged as a vital biomarker with significant implications forinnovative treatment modalities, particularly in immunotherapy. This receptoris predominantly expressed on cancer stem cells, which play a pivotal role intumorigenesis and contribute to therapeutic resistance. Elevated levels of CD44are associated with aggressive cancer phenotypes, including enhanced metastaticpotential and increased resistance to chemotherapy. Therefore, targeting CD44may enhance the efficacy of cancer treatments. Notably, CD44 exists in multipleisoforms, each exhibiting unique expression patterns across different tissues andtypes of cancer, highlighting the need for a refined approach to clinical targeting.The variations among these isoforms can influence tumor behavior and treatmentresponses, underscoring the importance of understanding these distinctions for theoptimization of therapeutic strategies. This review aims to delineate key aspectsof breast cancer, emphasize the significance of the CD44 biomarker, and explorethe implications of its isoforms in diagnosis and treatment. By scrutinizing theseelements, we seek to clarify the role of CD44 in cancer biology and its potential forenhancing treatment approaches in breast cancer and other malignancies
Gheybi et al. (Sun,) studied this question.