mouse prostate cancer cell line  (ATCC)

Journal: Journal of Experimental & Clinical Cancer Research : CR

Article Title: Mutant p53 epigenetically rewires CXCL10 to promote CD8⁺ T-cell infiltration and enhance the anti-PD-1 response in advanced prostate cancer

doi: 10.1186/s13046-026-03672-z

Figure Lengend Snippet: Trp53 p.R245Q promotes prostate tumor growth and remodels the tumor microenvironment. a Schematic of CRISPR/Cas9-mediated knock-in of Trp53 p.R245Q (arginine→glutamine) in prostate cancer cells and the workflow for in vivo validation and single-cell RNA sequencing. b-d Subcutaneous tumor growth of Myc-CaP cells in FVB/NJ mice (1 × 10 6 cells, WTp53 n = 5; Mutp53 n = 5): representative images of tumors at the experimental endpoint ( b ), tumor growth curves ( c ), and endpoint tumor weights ( d ). Tumors derived from Mutp53-expressing Myc-CaP cells exhibited significantly accelerated growth compared with those derived from control cells ( p < 0.05). e-g Subcutaneous tumor growth of RM-1 cells (1 × 10 6 cells in a Matrigel/PBS mixture) in C57BL/6 mice: representative endpoint tumor images ( e ), longitudinal tumor volume curves ( f ), and final tumor weights at sacrifice ( g ). Compared with those derived from WTp53 control cells, the tumors derived from Mutp53-expressing RM-1 cells markedly accelerated progression (WTp53 n = 5; Mutp53 n = 5; p < 0.05). h Kaplan-Meier survival analysis of subcutaneous RM-1 tumor-bearing mice injected with 5 × 10 5 cells: Compared with WTp53 controls, Mutp53-bearing mice presented significantly shorter overall survival (WTp53 n = 8; Mutp53 n = 10; log-rank test, p = 0.0156). i Dot plot visualization of canonical marker gene expression across major cell types in the single-cell transcriptome dataset derived from orthotopic RM-1 prostate tumors (5 × 10 5 cells implanted), including epithelial cells, endothelial cells, monocytes/macrophages, T/NK cells, fibroblasts, and pericytes, used for cell type annotation. j UMAP visualization of single-cell transcriptomes showing the distribution of major annotated cell types, along with representative top differentially expressed gene modules. k Fractional abundance of major cell populations in the tumor microenvironment. Box plots showing the relative fractions of epithelial cells, endothelial cells, pericytes, monocytes/macrophages, fibroblasts, and T/NK cells in tumors from the WTp53 and Mutp53 groups derived from single-cell transcriptome analysis. Among these populations, fibroblasts were obviously reduced in Mutp53 tumors, whereas changes in other cell types did not reach statistical significance. l Heatmap of observed-to-expected ratios for major cell populations. The Ro/e ratio was calculated for fibroblasts, pericytes, epithelial cells, monocytes/macrophages, endothelial cells, and T/NK cells in WTp53 and Mutp53 tumors. Compared with WTp53 tumors, Mutp53 tumors presented reduced fibroblast and pericyte enrichment, whereas monocytes/macrophages were relatively enriched. m Multiplex immunofluorescence staining of tumor sections for Pan-CK, CD4, FoxP3, CD8, CD68, CD163, and CTLA-4; Mutp53 tumors exhibit increased infiltration of CD4 + FoxP3+ regulatory T cells, CD8 + cytotoxic T cells, and CD68+/CD163 + macrophages, alongside elevated CTLA-4 expression. Scale bars: 100 μm. Note: Unless otherwise specified, p < 0.05 was considered statistically significant. Significance levels are indicated as follows: p < 0.05 (*), p < 0.01 (**), and p < 0.001 (***). Abbreviations: WTp53: Wild-type p53; Mutp53: Mutant p53 ( Trp53 p.R245Q, arginine to glutamine substitution); CRISPR: Clustered Regularly Interspaced Short Palindromic Repeats; Cas9: CRISPR-associated protein 9; scRNA-seq: Single-cell RNA sequencing; UMAP: Uniform Manifold Approximation and Projection; Ro/e: Ratio of observed-to-expected frequency; Mon/Macro: Monocytes/Macrophages; T/NK cells: T lymphocytes/Natural Killer cells; Fibro: Fibroblasts; Peri: Pericytes; Endo: Endothelial cells; Epi: Epithelial cells

Article Snippet: The mouse prostate cancer cell lines RM-1 (CRL-3310TM) and MyC-CaP (CRL-3255TM) were obtained from the Cell Bank of the Chinese Academy of Sciences (Shanghai, China), which provides authenticated lines originally sourced from the American Type Culture Collection (ATCC; Manassas, VA, USA).

Techniques: CRISPR, Knock-In, In Vivo, Biomarker Discovery, Single Cell, RNA Sequencing, Derivative Assay, Expressing, Control, Injection, Marker, Gene Expression, Multiplex Assay, Immunofluorescence, Staining, Mutagenesis

Journal: Journal of Experimental & Clinical Cancer Research : CR

Article Title: Mutant p53 epigenetically rewires CXCL10 to promote CD8⁺ T-cell infiltration and enhance the anti-PD-1 response in advanced prostate cancer

doi: 10.1186/s13046-026-03672-z

Figure Lengend Snippet: Mutant p53 tumors exhibit enhanced sensitivity to PD-1 blockade through augmented CD8 + cytotoxic programs. a Schematic of the experimental design for the subcutaneous and orthotopic RM-1 tumor models treated with an anti-PD-1 antibody. b-d Subcutaneous tumor growth of WTp53 and Mutp53 RM-1 tumors established by injection of 1 × 10 6 cells, with or without anti-PD-1 therapy: representative images ( b ), tumor volume curves ( c ), and endpoint tumor weights ( d ) ( n = 5 per group, one-way ANOVA with Tukey’s test). e-g Orthotopic tumor growth of WTp53 and Mutp53 RM-1 tumors established by prostate implantation of 5 × 10 5 cells following PD-1 blockade: representative images ( e ), tumor volumes ( f ), and endpoint tumor weights ( g ) ( n = 4–5 per group, one-way ANOVA with Tukey’s test). h-i Flow cytometric analysis of intratumoral CD8 + GZMB + T cells at baseline and after PD-1 blockade; quantification is shown in (I) (one-way ANOVA with Tukey’s test). j-k Single-cell RNA-seq clustering of CD8 + T-cell subsets, highlighting enrichment of CD8+, CD8 + CD69+, CD8 + GZMA+GZMB+, CD8 + NKG7+, and CD4 + CD8+ T cells in Mutp53 tumors relative to WTp53 tumors. l-s Functional module scoring of CD8 + T cells, showing comparable costimulatory ( l-m ), exhausted ( n-o ), and resident ( r-s ) signatures between groups but markedly increased cytotoxic signatures in Mutp53 tumors ( p-q ). t Expression of representative effector genes in intratumoral CD8 + T cells, showing upregulation of Nkg7 , Gzmb , and Slamf7 in Mutp53 tumors, whereas Ifng expression remained unchanged (see also Fig. S4a). u Multiplex immunofluorescence staining for CD8 and GZMB, showing increased infiltration of CD8 + GZMB + T cells in Mutp53 tumors at baseline and after PD-1 blockade, alongside reduced IFN-γ expression, compared with WTp53 (see also Fig. S4b-c). Note: Data are presented as the mean ± SEM. * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001; ns, not significant. Abbreviations: Mutp53, mutant p53; WTp53, wild-type p53; PD-1, programmed cell death protein-1; scRNA-seq, single-cell RNA sequencing; GZMA, granzyme A; GZMB, granzyme B; IFN-γ, interferon-γ; UMAP, uniform manifold approximation and projection

Article Snippet: The mouse prostate cancer cell lines RM-1 (CRL-3310TM) and MyC-CaP (CRL-3255TM) were obtained from the Cell Bank of the Chinese Academy of Sciences (Shanghai, China), which provides authenticated lines originally sourced from the American Type Culture Collection (ATCC; Manassas, VA, USA).

Techniques: Mutagenesis, Injection, Single Cell, RNA Sequencing, Functional Assay, Expressing, Multiplex Assay, Immunofluorescence, Staining

Journal: Journal of Experimental & Clinical Cancer Research : CR

Article Title: Mutant p53 epigenetically rewires CXCL10 to promote CD8⁺ T-cell infiltration and enhance the anti-PD-1 response in advanced prostate cancer

doi: 10.1186/s13046-026-03672-z

Figure Lengend Snippet: Mutp53 promotes immunotherapy responsiveness through CXCL10-CXCR3-mediated recruitment and activation of CD8 + T cells. a-b Heatmap ( a ) and qRT-PCR analysis ( b ) of immune-related chemokine expression in subcutaneous WTp53 and Mutp53 tumors, showing significant upregulation of Cxcl10 together with Cxcl1 , Cxcl2 , Cxcl12 , Ccl2 , and Cxcl9 in Mutp53 tumors compared with WTp53 tumors. c Correlation analysis of CXCL10 expression with immune-related signaling pathways in the IMvigor210 urothelial carcinoma cohort treated with immune checkpoint blockade, revealing strong positive associations with IFN-γ-related signatures and the antigen presentation machinery (APM). d Representative immunohistochemical (IHC) staining of CXCL10 in WTp53 and Mutp53 tumors. e-f Immunoblot analysis ( e ) and quantitative densitometry ( f ) of CXCL10 protein expression in WTp53 and Mutp53 tumor cell lines and corresponding tumor tissues. g Transwell coculture assays demonstrating enhanced chemotaxis of CD8 + T cells toward Mutp53-derived tumor cells compared with WTp53-derived tumor cells ( n = 3). h Clinical association between intratumoral CXCL10 expression and immune checkpoint blockade (ICB) benefit in the IMvigor210 cohort, with higher CXCL10 levels predicting improved therapeutic response. i Schematic illustration of the in vivo experimental design for pharmacological disruption of the CXCL10-CXCR3 axis using the CXCR3 antagonist AMG-487 during anti-PD-1 treatment, with RM-1 tumors established by subcutaneous injection of 1 × 10⁶ cells. j-l Representative tumor images ( j ), tumor growth curves ( k ), and endpoint tumor weights ( l ) of WTp53- and Mutp53-bearing mice treated with anti-PD-1 therapy in the presence or absence of AMG-487 ( n = 5 per group). CXCR3 blockade markedly attenuated the therapeutic efficacy of PD-1 blockade, with a substantially stronger reversal observed in Mutp53 tumors. m Serum biochemical analyses evaluating liver and kidney function, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), urea (BUN), and creatinine (CREA), showing no significant differences among treatment groups, indicating minimal systemic toxicity of AMG-487. n Multiplex immunofluorescence staining of tumor sections for CD8 (green), granzyme B (GZMB; red), and nuclei (DAPI; blue), revealing that anti-PD-1 therapy markedly increased infiltration of GZMB+CD8 + T cells in Mutp53 tumors, whereas CXCR3 inhibition significantly impaired this recruitment. o Quantification of GZMB+CD8 + T cells across treatment groups, confirming that the enrichment induced by PD-1 blockade in Mutp53 tumors was largely abolished by AMG-487 treatment. Note: Data are presented as the mean ± SD. Statistical significance was assessed using one-way or two-way ANOVA with Tukey’s multiple-comparison test, as appropriate. p < 0.05, p < 0.01, * p < 0.001; ns, not significant

Article Snippet: The mouse prostate cancer cell lines RM-1 (CRL-3310TM) and MyC-CaP (CRL-3255TM) were obtained from the Cell Bank of the Chinese Academy of Sciences (Shanghai, China), which provides authenticated lines originally sourced from the American Type Culture Collection (ATCC; Manassas, VA, USA).

Techniques: Activation Assay, Quantitative RT-PCR, Expressing, Protein-Protein interactions, Immunopeptidomics, Immunohistochemical staining, Immunohistochemistry, Western Blot, Chemotaxis Assay, Derivative Assay, Clinical Proteomics, In Vivo, Disruption, Injection, Drug discovery, Multiplex Assay, Immunofluorescence, Staining, Inhibition, Comparison

Journal: Journal of Experimental & Clinical Cancer Research : CR

Article Title: Mutant p53 epigenetically rewires CXCL10 to promote CD8⁺ T-cell infiltration and enhance the anti-PD-1 response in advanced prostate cancer

doi: 10.1186/s13046-026-03672-z

Figure Lengend Snippet: Mutant p53 occupies the Cxcl10 promoter and remodels promoter-proximal chromatin to enable Cxcl10 transcription. a Immunoblot of RM-1 tumors showing that siRNA-mediated Trp53 silencing reduces the CXCL10 protein. p53 and GAPDH were used as target and loading controls, respectively. b JASPAR motif analysis identifying putative p53-binding sequences within the Cxcl10 promoter. The schematic shows the positions of Primer 1 and Primer 2 relative to the transcription start site and Exon 1. c-d ChIP-qPCR analysis of p53 occupancy at the Cxcl10 promoter. Mutp53 was more strongly enriched than WTp53 at Primer 2, whereas enrichment at Primer 1 was modest. The signals are normalized to the input signal and expressed relative to the IgG signal. e-f Histone-mark ChIP-qPCR analysis of the Cxcl10 promoter. At Primer 1 ( e ), H3K4me3 is minimally enriched in WTp53 tumors but is increased in Mutp53 tumors. At Primer 2 ( f ), Mutp53 tumors display increased H3K4me3 together with reduced H3K27me3 and H3K36me3, which is consistent with a promoter environment permissive for transcription. IgG, negative control. g Agarose-gel electrophoresis of representative ChIP amplicons validating the expected products for the indicated antibodies in WTp53 and Mutp53 tumors; left, bp ladder. h Working model: Mutp53 preferentially occupies the Cxcl10 promoter (primer 2), recruits the activating machinery, increases H3K4me3, and relieves repressive marks (H3K27me3, H3K36me3) relative to WTp53, thereby facilitating RNA polymerase II-driven Cxcl10 transcription. Note: Statistics. The dots represent biologically independent samples (typically n = 3 per group); the bars represent the means ± SEMs. Unless otherwise indicated, ChIP-qPCR datasets in c-f were analyzed via two-way ANOVA followed by multiple comparisons tests. Significance thresholds: ns, not significant; * p < 0.05; ** p < 0.01; *** p < 0.001. Abbreviations: WTp53, wild-type p53; Mutp53, mutant p53; siRNA, small interfering RNA; ChIP, chromatin immunoprecipitation; qPCR, quantitative PCR; IgG, immunoglobulin G control IP; Pol II, RNA polymerase II; TSS, transcription start site; SEM, standard error of the mean; bp, base pairs; kDa, kilodaltons

Article Snippet: The mouse prostate cancer cell lines RM-1 (CRL-3310TM) and MyC-CaP (CRL-3255TM) were obtained from the Cell Bank of the Chinese Academy of Sciences (Shanghai, China), which provides authenticated lines originally sourced from the American Type Culture Collection (ATCC; Manassas, VA, USA).

Techniques: Mutagenesis, Western Blot, Binding Assay, ChIP-qPCR, Negative Control, Agarose Gel Electrophoresis, Small Interfering RNA, Chromatin Immunoprecipitation, Real-time Polymerase Chain Reaction, Control