DUGi

Avaluació de l’enriquiment de cèl·lules mare canceroses en línies cel·lulars de càncer de mama triple negatiu (TNBC) cultivades en scaffolds 3D

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Triple-negative breast cancer (TNBC) is one of the most aggressive subtypes of the disease, characterized by high recurrence rates and resistance to conventional treatments. One major cause of this aggressiveness is the presence of cancer stem cells (BCSCs), which drive tumor initiation, metastasis, and immune evasion. These cells can be identified by the CD44⁺/CD24⁻ phenotype and the expression of pluripotency markers and embryonic signaling pathways. However, their study is limited by traditional two-dimensional (2D) culture systems, which fail to faithfully replicate the tumor microenvironment. To overcome this, three-dimensional (3D) systems have emerged, such as scaffolds obtained via electrospinning, which better mimic the architecture and physical properties of the extracellular matrix. This work evaluated the expression of stemness- and development-related markers in the MDA-MB-231 cell line, cultured under 2D and 3D conditions for 3 and 6 days. The results show an initial increase (at day 3) in colony-forming capacity in 3D cultures, indicating a functional enrichment of cells with BCSC-like characteristics. Transcriptomic analysis revealed a progressive increase in the expression of genes such as CD44, SOX2, and β-CAT by day 6, suggesting a cellular response induced by the 3D microenvironment. At the protein level, discrepancies were observed compared to mRNA expression, likely due to post-transcriptional regulation or post-translational modifications, particularly for markers with low basal expression such as CD24 or CD133. In addition, while total STAT3 levels remained stable, its phosphorylated form (p-STAT3) significantly decreased at day 6, which may reflect progressive deactivation of signaling pathways involved in proliferation as an adaptive response. Overall, these findings indicate that 3D scaffold culture promotes the acquisition of a more plastic, stem-like phenotype, supporting its relevance as a preclinical model for TNBC research

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