Language：English   Publisher：Nature Communications  

Prostate cancer harboring BRCA1/2 mutations are often exceptionally sensitive to PARP inhibitors. However, genomic alterations in other DNA damage response genes have not been consistently predictive of clinical response to PARP inhibition. Here, we perform genome-wide CRISPR-Cas9 knockout screens in BRCA1/2-proficient prostate cancer cells and identify previously unknown genes whose loss has a profound impact on PARP inhibitor response. Specifically, MMS22L deletion, frequently observed (up to 14%) in prostate cancer, renders cells hypersensitive to PARP inhibitors by disrupting RAD51 loading required for homologous recombination repair, although this response is TP53-dependent. Unexpectedly, loss of CHEK2 confers resistance rather than sensitivity to PARP inhibition through increased expression of BRCA2, a target of CHEK2-TP53-E2F7-mediated transcriptional repression. Combined PARP and ATR inhibition overcomes PARP inhibitor resistance caused by CHEK2 loss. Our findings may inform the use of PARP inhibitors beyond BRCA1/2-deficient tumors and support reevaluation of current biomarkers for PARP inhibition in prostate cancer.

DOI： 10.1038/s41467-023-35880-y

Web of Science

Scopus

PubMed

Language：English   Publisher：Cell Reports  

Hematopoiesis was considered a hierarchical stepwise process but was revised to a continuous process following single-cell RNA sequencing. However, the uncertainty or fluctuation of single-cell transcriptome dynamics during differentiation was not considered, and the dendritic cell (DC) pathway in the lymphoid context remains unclear. Here, we identify human B-plasmacytoid DC (pDC) bifurcation as large fluctuating transcriptome dynamics in the putative B/NK progenitor region by dry and wet methods. By converting splicing kinetics into diffusion dynamics in a deep generative model, our original computational methodology reveals strong fluctuation at B/pDC bifurcation in IL-7Rα+ regions, and LFA-1 fluctuates positively in the pDC direction at the bifurcation. These expectancies are validated by the presence of B/pDC progenitors in the IL-7Rα+ fraction and preferential expression of LFA-1 in pDC-biased progenitors with a niche-like culture system. We provide a model of fluctuation-based differentiation, which reconciles continuous and discrete models and is applicable to other developmental systems.

DOI： 10.1016/j.celrep.2022.111260

Web of Science

Scopus

PubMed

Language：English   Publisher：Journal for ImmunoTherapy of Cancer  

Background Immune checkpoint blockade (ICB) induces durable clinical responses in patients with various types of cancer. However, its limited clinical efficacy requires the development of better approaches. In addition to immune checkpoint molecules, tumor-infiltrating immunosuppressive cells including regulatory T cells (Tregs) play crucial roles in the immune suppressive tumor microenvironment. While phosphatidylinositol 3-kinase (PI3K) inhibition as a Treg-targeted treatment has been implicated in animal models, its effects on human Tregs and on the potential impairment of effector T cells are required to be clarified for successful cancer immunotherapy. Methods The impact of a selective-PI3K inhibitor ZSTK474 with or without anti-programmed cell death 1 (PD-1) monoclonal antibody on Tregs and CD8 + T cells were examined with in vivo animal models and in vitro experiments with antigen specific and non-specific fashions using peripheral blood from healthy individuals and cancer patients. Phenotypes and functions of Tregs and effector T cells were examined with comprehensive gene and protein expression assays. Results Improved antitumor effects by the PI3K inhibitor in combination with ICB, particularly PD-1 blockade, were observed in mice and humans. Although administration of the PI3K inhibitor at higher doses impaired activation of CD8 + T cells as well as Tregs, the optimization (doses and timing) of this combination treatment selectively decreased intratumoral Tregs, resulting in increased tumor antigen-specific CD8 + T cells in the treated mice. Moreover, on the administration of the PI3K inhibitor with the optimal dose for selectively deleting Tregs, PI3K signaling was inhibited not only in Tregs but also in activated CD8 + T cells, leading to the enhanced generation of tumor antigen-specific memory CD8 + T cells which contributed to durable antitumor immunity. These opposing outcomes between Tregs and CD8 + T cells were attributed to the high degree of dependence on T cell signaling in the former but not in the latter. Conclusions PI3K inhibitor in the combination with ICB with the optimized protocol fine-tuned T cell activation signaling for antitumor immunity via decreasing Tregs and optimizing memory CD8 + T cell responses, illustrating a promising combination therapy.

DOI： 10.1136/jitc-2020-002279

Web of Science

Scopus

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.molcel.2020.04.027

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/s41467-019-12125-5

Web of Science

Scopus

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

We have previously reported that promoter polymorphism of myocardin-related transcription factor A (MRTF-A) is associated with coronary atherosclerosis. However, the contribution of MRTF-A to the development of atherosclerosis remains unknown. Macrophages are known to be important mediators of atherosclerosis. It has been demonstrated that local proliferation and survival of macrophages are atherogenic. In this study, we found that MRTF-A was highly expressed in lesional macrophages in human carotid atherosclerotic plaque. We then investigated the role of macrophagic MRTF-A in the pathogenesis of atherosclerosis. ApoE null MRTF-A transgenic mice (ApoE−/−/MRTF-Atg/+), in which human MRTF-A was specifically overexpressed in monocytes/macrophages, were established and fed with normal diet to examine the progression of atherosclerosis. We found that ApoE−/−/MRTF-Atg/+ aggravated atherosclerosis and lesional macrophages were more prominently accumulated in the aortic sinus of ApoE−/−/MRTF-Atg/+ than in that of ApoE−/− littermates. We also found that MRTF-A promoted proliferation and mitigated apoptosis of macrophages both in vitro and in vivo, and down regulated the expression of cyclin-dependent kinase inhibitors. From these findings, we conclude that MRTF-A modulates functional properties of pro-atherogenic macrophages. Our study may play a valuable role in understanding the pathological role of macrophagic MRTF-A in the progression of atherosclerosis.

DOI： 10.1016/j.yjmcc.2019.05.015

Scopus

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.tcb.2019.03.003

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER ASSOC CANCER RESEARCH  

The oncogenic MUC1-C protein is overexpressed in triple-negative breast cancer (TNBC) cells and contributes to their epigenetic reprogramming and chemoresistance. Here we show that targeting MUC1-C genetically or pharmacologically with the GO-203 inhibitor, which blocks MUC1-C nuclear localization, induced DNA double-strand breaks and potentiated cisplatin (CDDP)-induced DNA damage and death. MUC1-C regulated nuclear localization of the polycomb group proteins BMI1 and EZH2, which formed complexes with PARP1 during the DNA damage response. Targeting MUC1-C downregulated BMI1-induced H2A ubiquitylation, EZH2-driven H3K27 trimethylation, and activation of PARP1. As a result, treatment with GO-203 synergistically sensitized both mutant and wild-type BRCA1 TNBC cells to the PARP inhibitor olaparib. These findings uncover a role for MUC1-C in the regulation of PARP1 and identify a therapeutic strategy for enhancing the effectiveness of PARP inhibitors against TNBC.

DOI： 10.1158/0008-5472.CAN-18-3259

Web of Science

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1371/journal.pgen.1008002

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.ccell.2018.10.014

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/s41586-018-0409-3

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Epigenetic modifications control cancer development and clonal evolution in various cancer types. Here, we show that loss of the male-specific histone demethylase lysine-specific demethylase 5D (KDM5D) encoded on the Y chromosome epigenetically modifies histone methylation marks and alters gene expression, resulting in aggressive prostate cancer. Fluorescent in situ hybridization demonstrated that segmental or total deletion of the Y chromosome in prostate cancer cells is one of the causes of decreased KDM5D mRNA expression. The result of ChIP-sequencing analysis revealed that KDM5D preferably binds to promoter regions with coenrichment of the motifs of crucial transcription factors that regulate the cell cycle. Loss of KDM5D expression with dysregulated H3K4me3 transcriptional marks was associated with acceleration of the cell cycle and mitotic entry, leading to increased DNA-replication stress. Analysis of multiple clinical data sets reproducibly showed that loss of expression of KDM5D confers a poorer prognosis. Notably, we also found stress-induced DNA damage on the serine/threonine protein kinase ATR with loss of KDM5D. In KDM5D-deficient cells, blocking ATR activity with an ATR inhibitor enhanced DNA damage, which led to subsequent apoptosis. These data start to elucidate the biological characteristics resulting from loss of KDM5D and also provide clues for a potential novel therapeutic approach for this subset of aggressive prostate cancer.

DOI： 10.1172/JCI96769

Web of Science

Scopus

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

An increasingly recognized component of resistance to tyrosine kinase inhibitors (TKI) involves persistence of a drug-tolerant subpopulation of cancer cells that survive despite effective eradication of the majority of the cell population. Multiple groups have demonstrated that these drug-tolerant persister cells undergo transcriptional adaptation via an epigenetic state change that promotes cell survival. Because this mode of TKI drug tolerance appears to involve transcriptional addiction to specific genes and pathways, we hypothesized that systematic functional screening of EGFR TKI/transcriptional inhibitor combination therapy would yield important mechanistic insights and alternative drug escape pathways. We therefore performed a genome-wide CRISPR/Cas9 enhancer/suppressor screen in EGFR-dependent lung cancer PC9 cells treated with erlotinib + THZ1 (CDK7/12 inhibitor) combination therapy, a combination previously shown to suppress drug-tolerant cells in this setting. As expected, suppression of multiple genes associated with transcriptional complexes (EP300, CREBBP, and MED1) enhanced erlotinib/THZ1 synergy. Unexpectedly, we uncovered nearly every component of the recently described ufmylation pathway in the synergy suppressor group. Loss of ufmylation did not affect canonical downstream EGFR signaling. Instead, absence of this pathway triggered a protective unfolded protein response associated with STING upregulation, promoting protumorigenic inflammatory signaling but also unique dependence on Bcl-xL. These data reveal that dysregulation of ufmylation and ER stress comprise a previously unrecognized TKI drug tolerance pathway that engages survival signaling, with potentially important therapeutic implications.Significance: These findings reveal a novel function of the recently described ufmylation pathway, an ER stress survival signaling in drug-tolerant persister cells, which has important biological and therapeutic implications. Cancer Res; 78(4); 1044-57. ©2017 AACR.

DOI： 10.1158/0008-5472.CAN-17-1904

Web of Science

Scopus

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER ASSOC CANCER RESEARCH  

The immune checkpoint ligand PD-L1 and the transmembrane mucin MUC1 are upregulated in triple-negative breast cancer (TNBC), where they contribute to its aggressive pathogenesis. Here, we report that genetic or pharmacological targeting of the oncogenic MUC1 subunit MUC1-C is sufficient to suppress PD-L1 expression in TNBC cells. Mechanistic investigations showed that MUC1-C acted to elevate PD-L1 transcription by recruitment of MYC and NF-kappa B p65 to the PD-L1 promoter. In an immunocompetent model of TNBC in which Eo771/MUC1-C cells were engrafted into MUC1 transgenic mice, we showed that targeting MUC1-C associated with PD-L1 suppression, increases in tumor- infiltrating CD8(+) T cells and tumor cell killing. MUC1 expressionin TNBCs also correlated inversely with CD8, CD69, and GZMB, and downregulation of these markers associated with decreased survival. Taken together, our findings show how MUC1 contributes to immune escape in TNBC, and they offer a rationale to target MUC1-C as a novel immunotherapeutic approach for TNBC treatment. (C) 2017 AACR.

DOI： 10.1158/0008-5472.CAN-17-1636

Web of Science

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/onc.2016.439

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1073/pnas.1600420113

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/srep26643

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/neuonc/not31