bioRxiv Science⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.1101/2024.07.15.603489

CD24a knockout transforms the tumor microenvironment from cold to hot by promoting tumor-killing immune cell infiltration in a murine triple-negative breast cancer model

Chan, S.-H.·Tseng, H.-J.·Wang, L.-H.
View original source ↗Export metadata ↓

Abstract

BackgroundCD24 plays a crucial role not only in promoting tumor progression and metastasis but also in modulating macrophage-mediated anti-tumor immunity. However, the impact of tumor CD24 on the immune landscape of the tumor microenvironment (TME) remains poorly explored. Here, we investigated the role of CD24a, murine CD24 gene, in the progression and immune dynamics of the tumor microenvironment (TME) in the 4T1 murine model of triple-negative breast cancer (TNBC). Methods: We employed Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR)/Cas9 technology to perform a gene knockout of Cd24a in 4T1 cells. Flow cytometry was utilized to analyze the distribution and number of immune cells, including myeloid-derived suppressor cells (MDSCs), natural killer (NK) cells, T cells, and macrophages, within tumors, spleens, and bone marrow. Immunofluorescence (IF) staining was used to detect these immune cells in tumor sections. Additionally, ANDOR Dragonfly High-Speed Confocal was used to perform three-dimensional (3D) mapping of mouse tumors. ResultsOur study showed that knocking out CD24a significantly impeded tumor progression and prolonged mouse survival. Flow cytometry and IF analysis revealed that the loss of CD24a transformed tumor microenvironment from cold to hot by promoting the infiltration of M1 macrophages, cytotoxic CD8+ T cells, and CD49b+ natural killer (NK) cells while reducing the recruitment and expansion of granulocytic myeloid-derived suppressor cells (gMDSCs) in the TME. Additionally, the 3D mapping of TME further validated the "hot state" of CD24a knockout tumors. ConclusionsOur study provides the first evidence that targeting CD24a could effectively reprogram the TME, enhancing its immunogenicity, and transforming immune cold tumors into hot tumors. This strategy may offer a promising therapeutic strategy for enhancing the immune response against poorly immunogenic tumors.

Explore related subjects

cancer biologyPreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Chan, S.-H., Tseng, H.-J., Wang, L.-H.. 2024-07-17. CD24a knockout transforms the tumor microenvironment from cold to hot by promoting tumor-killing immune cell infiltration in a murine triple-negative breast cancer model. https://doi.org/10.1101/2024.07.15.603489

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

Tissue resident CD4+ memory T-cells mark response to immune checkpoint inhibition in high-grade glioma

Background: Immune checkpoint inhibitors (ICI) are efficacious in many solid tumors, but response in glioma is restricted to a small subgroup. The determinants of response and resistance to ICI remain poorly understood. Methods: Here we exploit a syngeneic hypermutated high-grade glioma model with dichotomous response to combined PD-1 and CTLA-4 inhibition to unravel determinants of tumor-infiltrating T-cells driving response. Tumor-infiltrating T-cells from ICI-responsive and non-responsive tumors were analyzed by single-cell RNA and T-cell receptor sequencing and tumor-reactive T-cell receptor clonotypes were functionally validated to characterize their transcriptional phenotypes. We verify our findings in IDH1 wildtype glioblastoma patients treated with neoadjuvant pembrolizumab. Results: ICI response was associated with intratumoral clonal expansion of tumor-reactive cytotoxic T-cells and increased infiltration of CXCR6+ CD4+ tissue resident memory T-cells (Trm). CD4 stem-like memory T-cells in responding tumors demonstrated elevated interferon responses, following trajectories toward clonally expanded Trm, versus trajectories toward exhaustion in non-responsive tumors. In responsive tumors, CD4+ Trm interacted with infiltrating CXCR3+ tumor-reactive and clonally expanded, yet transcriptionally versatile cytotoxic T-cells. Probing the post neoadjuvant ICI high-grade glioma patient tissue dataset, we confirmed increased CXCR6 expression in CD4+ T cells and the association of CD4+ Trm with prolonged overall survival. Conclusion: These findings identify CD4 tissue-resident memory T-cells as determinants of ICI response in IDH1 wildtype high-grade glioma and warrant their further investigation to improve immunotherapy outcomes.

cancer biology↗
bioRxiv2026

Circadian gene-network distortion in high-risk neuroblastoma across multiple biological reference contexts

Background: The circadian clock regulates cellular homeostasis, and its disruption has been implicated in aggressive neuroblastoma, particularly in tumours harbouring MYCN- amplification. However, it remains unclear whether alterations are restricted to individual clock genes or extend to circadian gene network coordination. We therefore examined circadian clock network disruption in adverse neuroblastoma across multiple biological contexts. Methods: We estimated circadian gene network dysregulation using Delta-CCD in tumours from two neuroblastoma cohorts (SEQC n=498 and Kocak n=649), comparing clinical features associated with outcome across canonical, adrenal-tissue matched, and developmental references. Robustness was assessed by cross-cohort meta-analysis and leave-one-gene-out analyses. Cox proportional hazards models adjusted for clinical covariates assessed association between individual clock gene expression patient outcome. Results: Delta-CCD was highest in tumours classified as high-risk (study-specific definition) across reference contexts in both cohorts. MYCN-amplified tumours showed a more reference-dependent pattern, strongest in adrenal context, while stage 4 tumours showed a similar but weaker pattern. Additional analyses supported the high-risk signal as a distributed network-level alteration rather than a single-gene phenomenon. Conclusions: High-risk neuroblastoma is characterised by robust disruption of coordinated clock gene network organisation across canonical and tissue-matched references, extending beyond individual clock genes. The extent of circadian dysregulation depends on the reference state used.

cancer biology↗
bioRxiv2026

BAP1 loss and PRAME expression converge to remodel the tumor-immune ecosystem during uveal melanoma progression

Uveal melanoma (UM) is characterized by a small number of recurrent genetic alterations that determine metastatic propensity. BAP1 loss and PRAME expression define the dominant prognostic axes in UM, yet how they promote malignant progression remains unclear. We profiled 190,535 cells from normal uvea, uveal nevus, primary and metastatic UM using single-cell transcriptomics, T cell receptor sequencing, spatial transcriptomics and isogenic perturbation models. Normal melanocytes, nevus cells and UM cells formed a transcriptional continuum marked by loss of differentiation and emergence of neural crest-like, stress-responsive, hypoxic-glycolytic and immune-interacting states. BAP1 loss and PRAME expression imposed distinct but convergent immunoregulatory programs, inducing interferon and TNF-NFkB signaling and MHC-I expression, with HLA-E showing the strongest response. These alterations were accompanied by macrophage and CD8+ T cell remodeling. PRAME-enriched tumor regions formed spatially organized niches enriched for macrophages and plasma cells. These findings define BAP1 loss and PRAME expression as distinct but convergent axes of tumor-immune coevolution and nominate HLA-E as a candidate mediator of immune resistance.

cancer biology↗