Glioblastoma multiforme (GBM) heterogeneity causes a greater number of deaths than any other brain tumor, despite the availability of alkylating chemotherapy. GBM stem-like cells (GSCs) contribute to GBM complexity and chemoresistance, but it remains challenging to identify and target GSCs or factors that control their activity. Here, we identified a specific GSC subset and show that activity of these cells is positively regulated by stabilization of methyl CpG binding domain 3 (MBD3) protein. MBD3 binds to CK1A and to BTRCP E3 ubiquitin ligase, triggering MBD3 degradation, suggesting that modulating this circuit could antagonize GBM recurrence. Accordingly, xenograft mice treated with the CK1A activator pyrvinium pamoate (Pyr-Pam) showed enhanced MBD3 degradation in cells expressing high levels of O6-methylguanine-DNA methyltransferase (MGMT) and in GSCs, overcoming temozolomide chemoresistance. Pyr-Pam blocked recruitment of MBD3 and the repressive nucleosome remodeling and deacetylase (NuRD) complex to neurogenesis-associated gene loci and increased acetyl–histone H3 activity and GSC differentiation. We conclude that CK1A/BTRCP/MBD3/NuRD signaling modulates GSC activation and malignancy, and that targeting this signaling could suppress GSC proliferation and GBM recurrence.
Byoung-San Moon, Mingyang Cai, Grace Lee, Tong Zhao, Xiaofeng Song, Steven L. Giannotta, Frank J. Attenello, Min Yu, Wange Lu
Angiosarcomas are rare, clinically aggressive tumors with limited treatment options and a dismal prognosis. We analyzed angiosarcomas from 68 patients, integrating information from multiomic sequencing, NanoString immuno-oncology profiling, and multiplex immunohistochemistry and immunofluorescence for tumor-infiltrating immune cells. Through whole-genome sequencing (n = 18), 50% of the cutaneous head and neck angiosarcomas exhibited higher tumor mutation burden (TMB) and UV mutational signatures; others were mutationally quiet and non–UV driven. NanoString profiling revealed 3 distinct patient clusters represented by lack (clusters 1 and 2) or enrichment (cluster 3) of immune-related signaling and immune cells. Neutrophils (CD15+), macrophages (CD68+), cytotoxic T cells (CD8+), Tregs (FOXP3+), and PD-L1+ cells were enriched in cluster 3 relative to clusters 2 and 1. Likewise, tumor inflammation signature (TIS) scores were highest in cluster 3 (7.54 vs. 6.71 vs. 5.75, respectively; P < 0.0001). Head and neck angiosarcomas were predominant in clusters 1 and 3, providing the rationale for checkpoint immunotherapy, especially in the latter subgroup with both high TMB and TIS scores. Cluster 2 was enriched for secondary angiosarcomas and exhibited higher expression of DNMT1, BRD3/4, MYC, HRAS, and PDGFRB, in keeping with the upregulation of epigenetic and oncogenic signaling pathways amenable to targeted therapies. Molecular and immunological dissection of angiosarcomas may provide insights into opportunities for precision medicine.
Jason Yongsheng Chan, Jing Quan Lim, Joe Yeong, Vinod Ravi, Peiyong Guan, Arnoud Boot, Timothy Kwang Yong Tay, Sathiyamoorthy Selvarajan, Nur Diyana Md Nasir, Jie Hua Loh, Choon Kiat Ong, Dachuan Huang, Jing Tan, Zhimei Li, Cedric Chuan-Young Ng, Thuan Tong Tan, Mikio Masuzawa, Ken Wing-Kin Sung, Mohamad Farid, Richard Hong Hui Quek, Ngian Chye Tan, Melissa Ching Ching Teo, Steven George Rozen, Patrick Tan, Andrew Futreal, Bin Tean Teh, Khee Chee Soo
ARID1A, a component of the chromatin-remodeling complex SWI/SNF, is one of the most frequently mutated genes in human cancer. We sought to develop rational combination therapy to potentiate the efficacy of immune checkpoint blockade in ARID1A-deficient tumors. In a proteomic analysis of a data set from The Cancer Genomic Atlas, we found enhanced expression of Chk2, a DNA damage checkpoint kinase, in ARID1A-mutated/deficient tumors. Surprisingly, we found that ARID1A targets the nonchromatin substrate Chk2 for ubiquitination. Loss of ARID1A increased the Chk2 level through modulating autoubiquitination of the E3-ligase RNF8 and thereby reducing RNF8-mediated Chk2 degradation. Inhibition of the ATM/Chk2 DNA damage checkpoint axis led to replication stress and accumulation of cytosolic DNA, which subsequently activated the DNA sensor STING-mediated innate immune response in ARID1A-deficient tumors. As expected, tumors with mutation or low expression of both ARID1A and ATM/Chk2 exhibited increased tumor-infiltrating lymphocytes and were associated with longer patient survival. Notably, an ATM inhibitor selectively potentiated the efficacy of immune checkpoint blockade in ARID1A-depleted tumors but not in WT tumors. Together, these results suggest that ARID1A’s targeting of the nonchromatin substrate Chk2 for ubiquitination makes it possible to selectively modulate cancer cell–intrinsic innate immunity to enhance the antitumor activity of immune checkpoint blockade.
Lulu Wang, Lin Yang, Chen Wang, Wei Zhao, Zhenlin Ju, Wei Zhang, Jianfeng Shen, Yang Peng, Clemens An, Yen T. Luu, Shumei Song, Timothy A. Yap, Jaffer A. Ajani, Gordon B. Mills, Xuetong Shen, Guang Peng
The undruggable nature of oncogenic Myc transcription factors poses a therapeutic challenge in neuroblastoma, a pediatric cancer in which MYCN amplification is strongly associated with unfavorable outcome. Here, we show that CYC065 (fadraciclib), a clinical inhibitor of CDK9 and CDK2, selectively targeted MYCN-amplified neuroblastoma via multiple mechanisms. CDK9 — a component of the transcription elongation complex P-TEFb — bound to the MYCN-amplicon superenhancer, and its inhibition resulted in selective loss of nascent MYCN transcription. MYCN loss led to growth arrest, sensitizing cells for apoptosis following CDK2 inhibition. In MYCN-amplified neuroblastoma, MYCN invaded active enhancers, driving a transcriptionally encoded adrenergic gene expression program that was selectively reversed by CYC065. MYCN overexpression in mesenchymal neuroblastoma was sufficient to induce adrenergic identity and sensitize cells to CYC065. CYC065, used together with temozolomide, a reference therapy for relapsed neuroblastoma, caused long-term suppression of neuroblastoma growth in vivo, highlighting the clinical potential of CDK9/2 inhibition in the treatment of MYCN-amplified neuroblastoma.
Evon Poon, Tong Liang, Yann Jamin, Susanne Walz, Colin Kwok, Anne Hakkert, Karen Barker, Zuzanna Urban, Khin Thway, Rhamy Zeid, Albert Hallsworth, Gary Box, Marli E. Ebus, Marco P. Licciardello, Yordan Sbirkov, Glori Lazaro, Elizabeth Calton, Barbara M. Costa, Melanie Valenti, Alexis De Haven Brandon, Hannah Webber, Nicolas Tardif, Gilberto S. Almeida, Rossitza Christova, Gunther Boysen, Mark W. Richards, Giuseppe Barone, Anthony Ford, Richard Bayliss, Paul A. Clarke, Johann De Bono, Nathanael S. Gray, Julian Blagg, Simon P. Robinson, Suzanne A. Eccles, Daniella Zheleva, James E. Bradner, Jan Molenaar, Igor Vivanco, Martin Eilers, Paul Workman, Charles Y. Lin, Louis Chesler
Psoriasis is a frequent, inflammatory skin disease characterized by keratinocyte hyperproliferation and a disease-related infiltration of immune cells. Here, we identified a novel proinflammatory signaling pathway driven by cyclin-dependent kinase 4 (CDK4) and CDK6 and the methyltransferase EZH2 as a valid target for psoriasis therapy. Delineation of the pathway revealed that CDK4/6 phosphorylated EZH2 in keratinocytes, thereby triggering a methylation-induced activation of STAT3. Subsequently, active STAT3 resulted in the induction of IκBζ, which is a key proinflammatory transcription factor required for cytokine synthesis in psoriasis. Pharmacological or genetic inhibition of CDK4/6 or EZH2 abrogated psoriasis-related proinflammatory gene expression by suppressing IκBζ induction in keratinocytes. Importantly, topical application of CDK4/6 or EZH2 inhibitors on the skin was sufficient to fully prevent the development of psoriasis in various mouse models by suppressing STAT3-mediated IκBζ expression. Moreover, we found a hyperactivation of the CDK4/6-EZH2 pathway in human and mouse psoriatic skin lesions. Thus, this study not only identifies a novel psoriasis-relevant proinflammatory pathway, but also proposes the repurposing of CDK4/6 or EZH2 inhibitors as a new therapeutic option for patients with psoriasis.
Anne Müller, Antje Dickmanns, Claudia Resch, Knut Schäkel, Stephan Hailfinger, Matthias Dobbelstein, Klaus Schulze-Osthoff, Daniela Kramer
Women with dense breasts have an increased lifetime risk of malignancy that has been attributed to a higher epithelial density. Quantitative proteomics, collagen analysis, and mechanical measurements in normal tissue revealed that stroma in the high-density breast contains more oriented, fibrillar collagen that is stiffer and correlates with higher epithelial cell density. microRNA (miR) profiling of breast tissue identified miR-203 as a matrix stiffness–repressed transcript that is downregulated by collagen density and reduced in the breast epithelium of women with high mammographic density. Culture studies demonstrated that ZNF217 mediates a matrix stiffness– and collagen density–induced increase in Akt activity and mammary epithelial cell proliferation. Manipulation of the epithelium in a mouse model of mammographic density supported a causal relationship between stromal stiffness, reduced miR-203, higher levels of the murine homolog Zfp217, and increased Akt activity and mammary epithelial proliferation. ZNF217 was also increased in the normal breast epithelium of women with high mammographic density, correlated positively with epithelial proliferation and density, and inversely with miR-203. The findings identify ZNF217 as a potential target toward which preexisting therapies, such as the Akt inhibitor triciribine, could be used as a chemopreventive agent to reduce cancer risk in women with high mammographic density.
Jason J. Northey, Alexander S. Barrett, Irene Acerbi, Mary-Kate Hayward, Stephanie Talamantes, Ivory S. Dean, Janna K. Mouw, Suzanne M. Ponik, Jonathon N. Lakins, Po-Jui Huang, Junmin Wu, Quanming Shi, Susan Samson, Patricia J. Keely, Rita A. Mukhtar, Jan T. Liphardt, John A. Shepherd, E. Shelley Hwang, Yunn-Yi Chen, Kirk C. Hansen, Laurie E. Littlepage, Valerie M. Weaver
Arginase 1 (Arg1), which converts l-arginine into ornithine and urea, exerts pleiotropic immunoregulatory effects. However, the function of Arg1 in inflammatory bowel disease (IBD) remains poorly characterized. Here, we found that Arg1 expression correlated with the degree of inflammation in intestinal tissues from IBD patients. In mice, Arg1 was upregulated in an IL-4/IL-13– and intestinal microbiota–dependent manner. Tie2-Cre Arg1fl/fl mice lacking Arg1 in hematopoietic and endothelial cells recovered faster from colitis than Arg1-expressing (Arg1fl/fl) littermates. This correlated with decreased vessel density, compositional changes in intestinal microbiota, diminished infiltration by myeloid cells, and an accumulation of intraluminal polyamines that promote epithelial healing. The proresolving effect of Arg1 deletion was reduced by an l-arginine–free diet, but rescued by simultaneous deletion of other l-arginine–metabolizing enzymes, such as Arg2 or Nos2, demonstrating that protection from colitis requires l-arginine. Fecal microbiota transfers from Tie2-Cre Arg1fl/fl mice into WT recipients ameliorated intestinal inflammation, while transfers from WT littermates into Arg1-deficient mice prevented an advanced recovery from colitis. Thus, an increased availability of l-arginine as well as altered intestinal microbiota and metabolic products accounts for the accelerated resolution from colitis in the absence of Arg1. Consequently, l-arginine metabolism may serve as a target for clinical intervention in IBD patients. IL-4/IL-13-
Julia Baier, Maximilian Gänsbauer, Claudia Giessler, Harald Arnold, Mercedes Muske, Ulrike Schleicher, Sören Lukassen, Arif Ekici, Manfred Rauh, Christoph Daniel, Arndt Ha rtmann, Benjamin Schmid, Philipp Tripal, Katja Dettmer, Peter J. Oefner, Raja Atreya, Stefan Wirtz, Christian Bogdan, Jochen Mattner
Although IKK-β has previously been shown as a negative regulator of IL-1β secretion in mice, this role has not been proven in humans. Genetic studies of NF-κB signaling in humans with inherited diseases of the immune system have not demonstrated the relevance of the NF-κB pathway in suppressing IL-1β expression. Here, we report an infant with a clinical pathology comprising neutrophil-mediated autoinflammation and recurrent bacterial infections. Whole-exome sequencing revealed a de novo heterozygous missense mutation of NFKBIA, resulting in a L34P IκBα variant that severely repressed NF-κB activation and downstream cytokine production. Paradoxically, IL-1β secretion was elevated in the patient’s stimulated leukocytes, in her induced pluripotent stem cell–derived macrophages, and in murine bone marrow–derived macrophages containing the L34P mutation. The patient’s hypersecretion of IL-1β correlated with activated neutrophilia and liver fibrosis with neutrophil accumulation. Hematopoietic stem cell transplantation reversed neutrophilia, restored a resting state in neutrophils, and normalized IL-1β release from stimulated leukocytes. Additional therapeutic blockade of IL-1 ameliorated liver damage, while decreasing neutrophil activation and associated IL-1β secretion. Our studies reveal a previously unrecognized role of human IκBα as an essential regulator of canonical NF-κB signaling in the prevention of neutrophil-dependent autoinflammatory diseases. These findings also highlight the therapeutic potential of IL-1 inhibitors in treating complications arising from systemic NF-κB inhibition.
Enrica E.K. Tan, Richard A. Hopkins, Chrissie K. Lim, Saumya S. Jamuar, Christina Ong, Koh C. Thoon, Mark J.A. Koh, Eun Mong Shin, Derrick W.Q. Lian, Madhushanee Weerasooriya, Christopher Z.W. Lee, Andreas Alvin Pumomo Soetedjo, Chang Siang Lim, Veonice B. Au, Edmond Chua, Hui Yin Lee, Leigh Ann Jones, Sharmy S. James, Nivashini Kaliaperumal, Jeffery Kwok, Ee Shien Tan, Biju Thomas, Lynn Xue Wu, Lena Ho, Anna Marie Fairhurst, Florent Ginhoux, Adrian K.K. Teo, Yong Liang Zhang, Kok Huar Ong, Weimiao Yu, Byrappa Venkatesh, Vinay Tergaonkar, Bruno Reversade, Keh Chuang Chin, Ah Moy Tan, Woei Kang Liew, John E. Connolly
Males and females differ in body composition and fat distribution. Using a mouse model that segregates gonadal sex (ovaries and testes) from chromosomal sex (XX and XY), we showed that XX chromosome complement in combination with a high-fat diet led to enhanced weight gain in the presence of male or female gonads. We identified the genomic dosage of Kdm5c, an X chromosome gene that escapes X chromosome inactivation, as a determinant of the X chromosome effect on adiposity. Modulating Kdm5c gene dosage in XX female mice to levels that are normally present in males resulted in reduced body weight, fat content, and food intake to a degree similar to that seen with altering the entire X chromosome dosage. In cultured preadipocytes, the levels of KDM5C histone demethylase influenced chromatin accessibility (ATAC-Seq), gene expression (RNA-Seq), and adipocyte differentiation. Both in vitro and in vivo, Kdm5c dosage influenced gene expression involved in extracellular matrix remodeling, which is critical for adipocyte differentiation and adipose tissue expansion. In humans, adipose tissue KDM5C mRNA levels and KDM5C genetic variants were associated with body mass. These studies demonstrate that the sex-dependent dosage of Kdm5c contributes to male/female differences in adipocyte biology and highlight X-escape genes as a critical component of female physiology.
Jenny C. Link, Carrie B. Wiese, Xuqi Chen, Rozeta Avetisyan, Emilio Ronquillo, Feiyang Ma, Xiuqing Guo, Jie Yao, Matthew Allison, Yii-Der Ida Chen, Jerome I. Rotter, Julia S. El -Sayed Moustafa, Kerrin S. Small, Shigeki Iwase, Matteo Pellegrini, Laurent Vergnes, Arthur P. Arnold, Karen Reue
Drivers of sporadic benign pituitary adenoma growth are largely unknown. Whole-exome sequencing of 159 prospectively resected pituitary adenomas showed that somatic copy number alteration (SCNA) rather than mutation is a hallmark of hormone-secreting adenomas and that SCNAs correlate with adenoma phenotype. Using single-gene SCNA pathway analysis, we observed that both cAMP and Fanconi anemia DNA damage repair pathways were affected by SCNAs in growth hormone–secreting (GH-secreting) somatotroph adenomas. As somatotroph differentiation and GH secretion are dependent on cAMP activation and we previously showed DNA damage, aneuploidy, and senescence in somatotroph adenomas, we studied links between cAMP signaling and DNA damage. Stimulation of cAMP in C57BL/6 mouse primary pituitary cultures using forskolin or a long-acting GH-releasing hormone (GHRH) analog increased GH production and DNA damage measured by H2AX phosphorylation and a comet assay. Octreotide, a somatostatin receptor ligand that targets somatotroph adenoma GH secretion in patients with acromegaly, inhibited cAMP and GH and reversed DNA damage induction. In vivo long-acting GHRH treatment also induced pituitary DNA damage in mice. We conclude that cAMP, which induces somatotroph proliferation and GH secretion, may concomitantly induce DNA damage, potentially linking hormone hypersecretion to SCNA and genome instability. These results elucidating somatotroph adenoma pathophysiology identify pathways for targeted treatment.
Anat Ben-Shlomo, Nan Deng, Evelyn Ding, Masaaki Yamamoto, Adam Mamelak, Vera Chesnokova, Artak Labadzhyan, Shlomo Melmed
No posts were found with this tag.