Cancers avoid immune surveillance through an array of mechanisms, including perturbation of HLA class I antigen presentation. Merkel cell carcinoma (MCC) is an aggressive, HLA-I–low, neuroendocrine carcinoma of the skin often caused by the Merkel cell polyomavirus (MCPyV). Through the characterization of 11 newly generated MCC patient-derived cell lines, we identified transcriptional suppression of several class I antigen presentation genes. To systematically identify regulators of HLA-I loss in MCC, we performed parallel, genome-scale, gain- and loss-of-function screens in a patient-derived MCPyV-positive cell line and identified MYCL and the non-canonical Polycomb repressive complex 1.1 (PRC1.1) as HLA-I repressors. We observed physical interaction of MYCL with the MCPyV small T viral antigen, supporting a mechanism of virally mediated HLA-I suppression. We further identify the PRC1.1 component USP7 as a pharmacologic target to restore HLA-I expression in MCC.
Patrick C. Lee, Susan Klaeger, Phuong M. Le, Keegan Korthauer, Jingwei Cheng, Varsha Ananthapadmanabhan, Thomas C. Frost, Jonathan D. Stevens, Alan Y.L. Wong, J. Bryan Iorgulescu, Anna Y. Tarren, Vipheaviny A. Chea, Isabel P. Carulli, Camilla K. Lemvigh, Christina B. Pedersen, Ashley K. Gartin, Siranush Sarkizova, Kyle T. Wright, Letitia W. Li, Jason Nomburg, Shuqiang Li, Teddy Huang, Xiaoxi Liu, Lucas Pomerance, Laura M. Doherty, Annie M. Apffel, Luke J. Wallace, Suzanna Rachimi, Kristen D. Felt, Jacquelyn O. Wolff, Elizabeth Witten, Wandi Zhang, Donna Neuberg, William J. Lane, Guanglan Zhang, Lars R. Olsen, Manisha Thakuria, Scott J. Rodig, Karl R. Clauser, Gabriel J. Starrett, John G. Doench, Sara J. Buhrlage, Steven A. Carr, James A. DeCaprio, Catherine J. Wu, Derin B. Keskin
Atrial fibrosis is an essential contributor to atrial fibrillation (AF). It remains unclear whether atrial endocardial endothelial cells (AEECs) that undergo endothelial-mesenchymal transition (EndMT) are among the sources of atrial fibroblasts. We studied human atria, TGF-β–treated human AEECs, cardiac-specific TGF-β–transgenic mice, and heart failure rabbits to identify the underlying mechanism of EndMT in atrial fibrosis. Using isolated AEECs, we found that miR-181b was induced in TGF-β–treated AEECs, which decreased semaphorin 3A (Sema3A) and increased EndMT markers, and these effects could be reversed by a miR-181b antagomir. Experiments in which Sema3A was increased by a peptide or decreased by a siRNA in AEECs revealed a mechanistic link between Sema3A and LIM-kinase 1/phosphorylated cofilin (LIMK/p-cofilin) signaling and suggested that Sema3A is upstream of LIMK in regulating actin remodeling through p-cofilin. Administration of the miR-181b antagomir or recombinant Sema3A to TGF-β–transgenic mice evoked increased Sema3A, reduced EndMT markers, and significantly decreased atrial fibrosis and AF vulnerability. Our study provides a mechanistic link between the induction of EndMT by TGF-β via miR-181b/Sema3A/LIMK/p-cofilin signaling to atrial fibrosis. Blocking miR-181b and increasing Sema3A are potential strategies for AF therapeutic intervention.
Ying-Ju Lai, Feng-Chun Tsai, Gwo-Jyh Chang, Shang-Hung Chang, Chung-Chi Huang, Wei-Jan Chen, Yung-Hsin Yeh
The roles of neutrophils in renal inflammation are currently unclear. On examining these cells in the unilateral ureteral obstruction murine model of chronic kidney disease, we found that the injured kidney bore a large and rapidly expanding population of neutrophils that expressed the eosinophil marker Siglec-F. We first verified that these cells were neutrophils. Siglec-F+ neutrophils were recently detected in several studies in other disease contexts. We then showed that a) these cells were derived from conventional neutrophils in the renal vasculature by TGF-β1 and GM-CSF; b) they differed from their parent cells by more frequent hypersegmentation, higher expression of profibrotic inflammatory cytokines, and notably, expression of collagen 1; and c) their depletion reduced collagen deposition and disease progression, but adoptive transfer increased renal fibrosis. These findings have thus unveiled a subtype of neutrophils that participate in renal fibrosis and a potentially new therapeutic target in chronic kidney disease.
Seungwon Ryu, Jae Woo Shin, Soie Kwon, Jiwon Lee, Yong Chul Kim, Yoe-Sik Bae, Yong-Soo Bae, Dong Ki Kim, Yon Su Kim, Seung Hee Yang, Hye Young Kim
Fibrodysplasia ossificans progressiva (FOP) is a rare genetic disorder whose most debilitating pathology is progressive and cumulative heterotopic ossification (HO) of skeletal muscles, ligaments, tendons, and fascia. FOP is caused by mutations in the type I BMP receptor gene ACVR1, which enable ACVR1 to utilize its natural antagonist, activin A, as an agonistic ligand. The physiological relevance of this property is underscored by the fact that HO in FOP is exquisitely dependent on activation of FOP-mutant ACVR1 by activin A, an effect countered by inhibition of anti–activin A via monoclonal antibody treatment. Hence, we surmised that anti-ACVR1 antibodies that block activation of ACVR1 by ligands should also inhibit HO in FOP and provide an additional therapeutic option for this condition. Therefore, we generated anti-ACVR1 monoclonal antibodies that block ACVR1’s activation by its ligands. Surprisingly, in vivo, these anti-ACVR1 antibodies stimulated HO and activated signaling of FOP-mutant ACVR1. This property was restricted to FOP-mutant ACVR1 and resulted from anti-ACVR1 antibody–mediated dimerization of ACVR1. Conversely, wild-type ACVR1 was inhibited by anti-ACVR1 antibodies. These results uncover an additional property of FOP-mutant ACVR1 and indicate that anti-ACVR1 antibodies should not be considered as therapeutics for FOP.
Senem Aykul, Lily Huang, Lili Wang, Nanditha M. Das, Sandra Reisman, Yonaton Ray, Qian Zhang, Nyanza Rothman, Kalyan C. Nannuru, Vishal Kamat, Susannah Brydges, Luca Troncone, Laura Johnsen, Paul B. Yu, Sergio Fazio, John Lees-Shepard, Kevin Schutz, Andrew J. Murphy, Aris N. Economides, Vincent Idone, Sarah J. Hatsell
CD4+ Th cells play a key role in orchestrating immune responses, but the identity of the CD4+ Th cells involved in the antitumor immune response remains to be defined. We analyzed the immune cell infiltrates of head and neck squamous cell carcinoma and colorectal cancers and identified a subset of CD4+ Th cells distinct from FOXP3+ Tregs that coexpressed programmed cell death 1 (PD-1) and ICOS. These tumor-infiltrating lymphocyte CD4+ Th cells (CD4+ Th TILs) had a tissue-resident memory phenotype, were present in MHC class II–rich areas, and proliferated in the tumor, suggesting local antigen recognition. The T cell receptor repertoire of the PD-1+ICOS+ CD4+ Th TILs was oligoclonal, with T cell clones expanded in the tumor, but present at low frequencies in the periphery. Finally, these PD-1+ICOS+ CD4+ Th TILs were shown to recognize both tumor-associated antigens and tumor-specific neoantigens. Our findings provide an approach for isolating tumor-reactive CD4+ Th TILs directly ex vivo that will help define their role in the antitumor immune response and potentially improve future adoptive T cell therapy approaches.
Rebekka Duhen, Olivier Fesneau, Kimberly A. Samson, Alexandra K. Frye, Michael Beymer, Venkatesh Rajamanickam, David Ross, Eric Tran, Brady Bernard, Andrew D. Weinberg, Thomas Duhen
Wnt signaling regulates the balance between stemness and differentiation in multiple tissues and in cancer. RNF43-mutant pancreatic cancers are dependent on Wnt production, and pharmacologic blockade of the pathway, e.g., by PORCN inhibitors, leads to tumor differentiation. However, primary resistance to these inhibitors has been observed. To elucidate potential mechanisms, we performed in vivo CRISPR screens in PORCN inhibitor–sensitive RNF43-mutant pancreatic cancer xenografts. As expected, genes in the Wnt pathway whose loss conferred drug resistance were identified, including APC, AXIN1, and CTNNBIP1. Unexpectedly, the screen also identified the histone acetyltransferase EP300 (p300), but not its paralog, CREBBP (CBP). We found that EP300 is silenced due to genetic alterations in all the existing RNF43-mutant pancreatic cancer cell lines that are resistant to PORCN inhibitors. Mechanistically, loss of EP300 directly downregulated GATA6 expression, thereby silencing the GATA6-regulated differentiation program and leading to a phenotypic transition from the classical subtype to the dedifferentiated basal-like/squamous subtype of pancreatic cancer. EP300 mutation and loss of GATA6 function bypassed the antidifferentiation activity of Wnt signaling, rendering these cancer cells resistant to Wnt inhibition.
Zheng Zhong, Nathan Harmston, Kris C. Wood, Babita Madan, David M. Virshup
Fibrodysplasia ossificans progressiva (FOP) is a rare genetic disease characterized by progressive and catastrophic heterotopic ossification (HO) of skeletal muscle and associated soft tissues. FOP is caused by dominantly acting mutations in the gene encoding the bone morphogenetic protein (BMP) type I receptor, ACVR1 (ALK2), the most prevalent of which results in an arginine to histidine substitution at position 206 (ACVR1[R206H]). The fundamental pathological consequence of FOP-causing ACVR1 receptor mutations is to enable activin A to initiate canonical BMP signaling in fibro-adipogenic progenitors (FAPs), which drives HO. We developed a monoclonal blocking antibody (JAB0505) against the extracellular domain of ACVR1 and tested its effect on HO in 2 independent FOP mouse models. Although JAB0505 inhibited BMP-dependent gene expression in wild-type and ACVR1(R206H)-overexpressing cell lines, JAB0505 treatment profoundly exacerbated injury-induced HO. JAB0505-treated mice exhibited multiple, distinct foci of heterotopic lesions, suggesting an atypically broad anatomical domain of FAP recruitment to endochondral ossification. This was accompanied by dysregulated FAP population growth and an abnormally sustained immunological reaction following muscle injury. JAB0505 drove injury-induced HO in the absence of activin A, indicating that JAB0505 has receptor agonist activity. These data raise serious safety and efficacy concerns for the use of bivalent anti-ACVR1 antibodies to treat patients with FOP.
John B. Lees-Shepard, Sean J. Stoessel, Julian T. Chandler, Keith Bouchard, Patricia Bento, Lorraine N. Apuzzo, Parvathi M. Devarakonda, Jeffrey W. Hunter, David J. Goldhamer
Once human photoreceptors die, they do not regenerate, thus, photoreceptor transplantation has emerged as a potential treatment approach for blinding diseases. Improvements in transplant organization, donor cell maturation, and synaptic connectivity to the host will be critical in advancing this technology for use in clinical practice. Unlike the unstructured grafts of prior cell-suspension transplantations into end-stage degeneration models, we describe the extensive incorporation of induced pluripotent stem cell (iPSC) retinal organoid–derived human photoreceptors into mice with cone dysfunction. This incorporative phenotype was validated in both cone-only as well as pan-photoreceptor transplantations. Rather than forming a glial barrier, Müller cells extended throughout the graft, even forming a series of adherens junctions between mouse and human cells, reminiscent of an outer limiting membrane. Donor-host interaction appeared to promote polarization as well as the development of morphological features critical for light detection, namely the formation of inner and well-stacked outer segments oriented toward the retinal pigment epithelium. Putative synapse formation and graft function were evident at both structural and electrophysiological levels. Overall, these results show that human photoreceptors interacted readily with a partially degenerated retina. Moreover, incorporation into the host retina appeared to be beneficial to graft maturation, polarization, and function.
Sylvia J. Gasparini, Karen Tessmer, Miriam Reh, Stephanie Wieneke, Madalena Carido, Manuela Völkner, Oliver Borsch, Anka Swiersy, Marta Zuzic, Olivier Goureau, Thomas Kurth, Volker Busskamp, Günther Zeck, Mike O. Karl, Marius Ader
Patients with high-risk, nonmuscle-invasive bladder cancer (NMIBC) frequently relapse after standard intravesical bacillus Calmette-Guérin (BCG) therapy and may have a dismal outcome. The mechanisms of resistance to such immunotherapy remain poorly understood. Here, using cancer cell lines, freshly resected human bladder tumors, and samples from cohorts of patients with bladder cancer before and after BCG therapy, we demonstrate 2 distinct patterns of immune subversion upon BCG relapse. In the first pattern, intracellular BCG infection of cancer cells induced a posttranscriptional downregulation of HLA-I membrane expression via inhibition of autophagy flux. Patients with HLA-I–deficient cancer cells following BCG therapy had a myeloid immunosuppressive tumor microenvironment (TME) with epithelial-mesenchymal transition (EMT) characteristics and dismal outcomes. Conversely, patients with HLA-I–proficient cancer cells after BCG therapy presented with CD8+ T cell tumor infiltrates, upregulation of inflammatory cytokines, and immune checkpoint–inhibitory molecules. The latter patients had a very favorable outcome. We surmise that HLA-I expression in bladder cancers at relapse following BCG does not result from immunoediting but rather from an immune subversion process directly induced by BCG on cancer cells, which predicts a dismal prognosis. HLA-I scoring of cancer cells by IHC staining can be easily implemented by pathologists in routine practice to stratify future treatment strategies for patients with urothelial cancer.
Mathieu Rouanne, Julien Adam, Camélia Radulescu, Diane Letourneur, Delphine Bredel, Séverine Mouraud, Anne-Gaëlle Goubet, Marion Leduc, Noah Chen, Tuan Zea Tan, Nicolas Signolle, Amélie Bigorgne, Michael Dussiot, Lambros Tselikas, Sandrine Susini, François-Xavier Danlos, Anna K. Schneider, Roman Chabanon, Sophie Vacher, Ivan Bièche, Thierry Lebret, Yves Allory, Jean-Charles Soria, Nicholas Arpaia, Guido Kroemer, Oliver Kepp, Jean Paul Thiery, Laurence Zitvogel, Aurélien Marabelle
Chimeric antigen receptor (CAR) T cell expansion and persistence represent key factors to achieve complete responses and prevent relapses. These features are typical of early memory T cells, which can be highly enriched through optimized manufacturing protocols. Here, we investigated the efficacy and safety profiles of CAR T cell products generated from preselected naive/stem memory T cells (TN/SCM), as compared with unselected T cells (TBULK). Notwithstanding their reduced effector signature in vitro, limiting CAR TN/SCM doses showed superior antitumor activity and the unique ability to counteract leukemia rechallenge in hematopoietic stem/precursor cell–humanized mice, featuring increased expansion rates and persistence together with an ameliorated exhaustion and memory phenotype. Most relevantly, CAR TN/SCM proved to be intrinsically less prone to inducing severe cytokine release syndrome, independently of the costimulatory endodomain employed. This safer profile was associated with milder T cell activation, which translated into reduced monocyte activation and cytokine release. These data suggest that CAR TN/SCM are endowed with a wider therapeutic index compared with CAR TBULK.
Silvia Arcangeli, Camilla Bove, Claudia Mezzanotte, Barbara Camisa, Laura Falcone, Francesco Manfredi, Eugenia Bezzecchi, Rita El Khoury, Rossana Norata, Francesca Sanvito, Maurilio Ponzoni, Beatrice Greco, Marta Angiola Moresco, Matteo G. Carrabba, Fabio Ciceri, Chiara Bonini, Attilio Bondanza, Monica Casucci
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