Cancer stem cells are responsible for breast cancer initiation, metastasis, and relapse. Targeting breast cancer stem cells (BCSCs) using phytochemicals is a good strategy for the treatment of cancer. A silica gel, a reversed-phase C18 column (ODS), a Sephadex LH-20 gel, thin layer chromatography, and high-performance liquid chromatography (HPLC) were used for compound isolation from Saururus chinensis extracts. The isolated compound was identified as machilin D by mass spectrometry and nuclear magnetic resonance (NMR). Machilin D inhibited the growth and mammosphere formation of breast cancer cells and inhibited tumor growth in a xenograft mouse model. Machilin D reduced the proportions of CD44⁺/CD24^- and aldehyde dehydrogenase 1 (ALDH1)-positive cells. Furthermore, this compound reduced the nuclear localization of the NF-κB protein and decreased the IL-6 and IL-8 secretion in mammospheres. These results suggest that machilin D blocks IL-6 and IL-8 signaling and induces CSC death and thus may be a potential agent targeting BCSCs.

Macrophages engineered with chimeric antigen receptors (CAR) are suitable for immunotherapy based on their immunomodulatory activity and ability to infiltrate solid tumours. However, the production and application of genetically edited, highly effective, and mass-produced CAR-modified macrophages (CAR-Ms) are challenging. Here, we used homology-independent targeted insertion (HITI) for site-directed CAR integration into the safe-harbour region of human pluripotent stem cells (hPSCs). This approach, together with a simple differentiation protocol, produced stable and highly effective CAR-Ms without heterogeneity. These engineered cells phagocytosed cancer cells, leading to significant inhibition of cancer-cell proliferation in vitro and in vivo. Furthermore, the engineered CARs, which incorporated a combination of CD3ζ and Megf10 (referred to as FRP5_Mζ), markedly enhanced the antitumour effect of CAR-Ms by promoting M1, but not M2, polarisation. FRP5_Mζ promoted M1 polarisation via nuclear factor kappa B (NF-κB), ERK, and STAT1 signalling, and concurrently inhibited STAT3 signalling even under M2 conditions. These features of CAR-Ms modulated the tumour microenvironment by activating inflammatory signalling, inducing M1 polarisation of bystander non-CAR macrophages, and enhancing the infiltration of T cells in cancer spheroids. Our findings suggest that CAR-Ms have promise as immunotherapeutics. In conclusion, the guided insertion of CAR containing CD3ζ and Megf10 domains is an effective strategy for the immunotherapy of solid tumours. This work was supported by KRIBB Research Initiative Program Grant (KGM4562431, KGM5282423) and a Korean Fund for Regenerative Medicine (KFRM) grant funded by the Korean government (Ministry of Science and ICT,Ministry of Health and Welfare) (22A0304L1-01).

Breast cancer is a major health problem that affects lives worldwide. Breast cancer stem cells (BCSCs) are small subpopulations of cells with capacities for drug resistance, self-renewal, recurrence, metastasis, and differentiation. Herein, powder extracts of beetroot were subjected to silica gel, gel filtration, thin layer chromatography (TLC), and preparatory high-pressure liquid chromatography (HPLC) for isolation of one compound, based on activity-guided purification using tumorsphere formation assays. The purified compound was identified as betavulgarin, using nuclear magnetic resonance spectroscopy and electrospray ionization (ESI) mass spectrometry. Betavulgarin suppressed the proliferation, migration, colony formation, and mammosphere formation of breast cancer cells and reduced the size of the CD44⁺/CD24⁻ subpopulation and the expression of the self-renewal-related genes, C-Myc, Nanog, and Oct4. This compound decreased the total level and phosphorylated nuclear level of signal transducer and activator of transcription 3 (Stat3) and reduced the mRNA and protein levels of sex determining region Y (SRY)-box 2 (SOX2), in mammospheres. These data suggest that betavulgarin inhibit the Stat3/Sox2 signaling pathway and induces BCSC death, indicating betavulgarin might be an anticancer agent against breast cancer cells and BCSCs.

In the complex tumor microenvironment, cancer stem cells (CSCs), a rare population of cells, are responsible for malignant tumor initiation, metastasis, drug resistance and recurrence. Controlling breast CSCs (BCSCs) using natural compounds is a novel potential therapeutic strategy for clinical cancer treatment. In this study, a mammosphere assay-guided isolation protocol including silica gel, a C18 column, gel filtration, and high-pressure liquid chromatography was used to isolate an inhibitory compound from Cynanchum auriculatum extracts. The isolated inhibitory compound was identified as caudatin. Caudatin inhibited breast cancer cell proliferation, mammosphere formation and tumor growth. Caudatin decreased the CD44⁺/CD24⁻ and aldehyde dehydrogenase⁺ cell proportions and the levels of c-Myc, Oct4, Sox2, and CD44. Caudatin induced ubiquitin (Ub)-dependent glucocorticoid receptor (GR) degradation and blocked subsequent Yes-associated protein (YAP) nuclear accumulation and target gene transcription signals in BCSCs. These results show that the GR/YAP signaling pathway regulates BCSC formation and that caudatin may be a potential chemopreventive agent that targets breast cancer cells and CSCs.

Cultured meat, a sustainable alternative to conventional meat, addresses ethical and environmental challenges in livestock production. Its production relies on bovine muscle stem cells from adult muscle or fetal tissue, whose proliferation and differentiation vary with age and developmental stage. However, the molecular mechanisms underlying these variations remain unclear. RNA sequencing was performed to characterize the transcriptomic landscape of bovine muscle stem cells across developmental stages, including myogenic maturation. Differentially expressed genes and key signaling pathways regulating myogenesis were identified, and the functional impact of modulating the AKT-autophagy pathway on differentiation was assessed. Transcriptomic analysis revealed distinct age-dependent gene expression patterns. It was possible to classify cells into three categories: young undifferentiated, young differentiated, and old differentiated. Young undifferentiated-like cells exhibited upregulation of genes associated with active states during the transitions from quiescence to activation and, ultimately, to commitment, indicating that they had robust differentiation potential. In contrast, aged myogenic samples displayed gene expression profiles that acted as barriers to efficient myogenic differentiation. Notably, modulation of the AKT-autophagy pathway both facilitated the production of very mature myogenic cells and prevented spontaneous differentiation, thereby preserving differentiation capacity in vitro. These findings provide insights into age-dependent muscle stem cell differentiation and suggest strategies to optimize cultured meat production. The appropriate modulation of key signaling pathways may help us to overcome major challenges in achieving scalable and efficient cultured meat manufacturing.

Autophagy plays a critical role in maintaining cellular homeostasis and regulating stem cell fate. Although microRNAs (miRNAs) are being increasingly recognized for their ability to modulate autophagy and pluripotency in human pluripotent stem cells (hPSCs), the underlying molecular mechanisms remain incompletely understood. This study defines a role for miR-150 deficiency in biasing ectoderm–mesoderm lineage specification in hPSCs and identifies SOX2 as a key downstream node regulated primarily through altered mRNA stability, with additional involvement of an autophagy-associated pathway. miR-150-deficient hPSCs were generated by CRISPR/Cas9-mediated deletion of the miR-150 locus. A range of molecular and cellular techniques were used to investigate how miR-150 regulates SOX2 and KLHL20 expression, modulates the KLHL20–ULK1 interaction, and influences autophagy-mediated SOX2 degradation. Directed differentiation protocols were used to determine the role of miR-150 in germ layer lineage specification. The loss of miR-150 led to increased SOX2 expression by stabilizing its mRNA, resulting in elevated SOX2 protein levels in hPSCs. Concurrently, miR-150 deficiency increased KLHL20 mRNA stability, disrupted ULK1-mediated autophagy, and inhibited SOX2 degradation. Functional assays demonstrated that miR-150 fine-tunes SOX2 expression through dual regulation of mRNA stability and autophagy via the KLHL20–ULK1 axis, maintaining a balanced commitment to the mesodermal and ectodermal lineages. These findings establish miR-150 as a regulator of SOX2 activity and autophagy in hPSCs. By targeting both SOX2 and the KLHL20–ULK1 axis, miR-150 coordinates SOX2 turnover through complementary mechanisms, ensuring precise mesodermal and ectodermal lineage commitment. This multiregulatory strategy provides new insights into how miRNAs integrate intracellular signaling pathways to direct stem cell fate decisions.