Stem cells
Abstract
Breast cancer stem cells (BCSCs) mitigate oxidative stress to maintain their viability and plasticity. However, the regulatory mechanism of oxidative stress in BCSCs remains unclear. We recently found that the histone reader ZMYND8 was upregulated in BCSCs. Here, we showed that ZMYND8 reduced ROS and iron to inhibit ferroptosis in aldehyde dehydrogenase (ALDH)high BCSCs, leading to BCSC expansion and tumor initiation in mice. The underlying mechanism involved a twofold posttranslational regulation of nuclear factor erythroid 2–related factor 2 (NRF2). ZMYND8 increased stability of NRF2 protein through KEAP1 silencing. On the other hand, ZMYND8 interacted with and recruited NRF2 to the promoters of antioxidant genes to enhance gene transcription in mammospheres. NRF2 phenocopied ZMYND8 to enhance BCSC stemness and tumor initiation by inhibiting ROS and ferroptosis. Loss of NRF2 counteracted ZMYND8’s effects on antioxidant genes and ROS in mammospheres. Interestingly, ZMYND8 expression was directly controlled by NRF2 in mammospheres. Collectively, these findings uncover a positive feedback loop that amplifies the antioxidant defense mechanism sustaining BCSC survival and stemness.
Authors
Maowu Luo, Lei Bao, Yuanyuan Xue, Ming Zhu, Ashwani Kumar, Chao Xing, Jennifer E Wang, Yingfei Wang, Weibo Luo
Abstract
Mutations in ATP-binding cassette A3 (ABCA3), a phospholipid transporter critical for surfactant homeostasis in pulmonary alveolar type II epithelial cells (AEC2s), are the most common genetic causes of childhood interstitial lung disease (chILD). Treatments for patients with pathological variants of ABCA3 mutations are limited, in part due to a lack of understanding of disease pathogenesis resulting from an inability to access primary AEC2s from affected children. Here, we report the generation of AEC2s from affected patient induced pluripotent stem cells (iPSCs) carrying homozygous versions of multiple ABCA3 mutations. We generated syngeneic CRISPR/Cas9 gene-corrected and uncorrected iPSCs and ABCA3-mutant knockin ABCA3:GFP fusion reporter lines for in vitro disease modeling. We observed an expected decreased capacity for surfactant secretion in ABCA3-mutant iPSC-derived AEC2s (iAEC2s), but we also found an unexpected epithelial-intrinsic aberrant phenotype in mutant iAEC2s, presenting as diminished progenitor potential, increased NFκB signaling, and the production of pro-inflammatory cytokines. The ABCA3:GFP fusion reporter permitted mutant-specific, quantifiable characterization of lamellar body size and ABCA3 protein trafficking, functional features that are perturbed depending on ABCA3 mutation type. Our disease model provides a platform for understanding ABCA3 mutation–mediated mechanisms of alveolar epithelial cell dysfunction that may trigger chILD pathogenesis.
Authors
Yuliang L. Sun, Erin E. Hennessey, Hillary Heins, Ping Yang, Carlos Villacorta-Martin, Julian Kwan, Krithi Gopalan, Marianne James, Andrew Emili, F. Sessions Cole, Jennifer A. Wambach, Darrell N. Kotton
Abstract
Authors
Vaidya Govindarajan, Jay Chandar, Avindra Nath, Ashish H. Shah
Abstract
Challenging skeletal repairs are frequently seen in patients experiencing systemic inflammation. To tackle the complexity and heterogeneity of skeletal repair process, we performed single-cell RNA sequencing and revealed that progenitor cell was one of the major lineages responsive to elevated inflammation and this response adversely affected progenitor differentiation by upregulation of Rbpjk in fracture nonunion. We then validated the interplay between inflammation (via Ikk2ca) and Rbpjk specifically in progenitors by using genetic animal models. Focusing on epigenetic regulation, we identified Rbpjk as a direct target of Dnmt3b. Mechanistically, inflammation decreased Dnmt3b expression in progenitor cells, consequently leading to Rbpjk upregulation via hypomethylation within its promoter region. We also showed that Dnmt3b loss-of-function mice phenotypically recapitulated the fracture repair defects observed in Ikk2ca mice, whereas Dnmt3b transgenic mice alleviated fracture repair defects induced by Ikk2ca. Moreover, Rbpjk ablation restored fracture repair in both Ikk2ca mice and Dnmt3b loss-of-function mice. Altogether, this work elucidates a common mechanism involving NFkB/Dnmt3b/Rbpjk axis within the context of inflamed bone regeneration. Building upon this mechanistic insight, we applied local treatment with epigenetically modified progenitor cells in RA mice and showed a functional restoration of bone regeneration under inflammatory condition through an increase in progenitor differentiation potential.
Authors
Ding Xiao, Liang Fang, Zhongting Liu, Yonghua He, Jun Ying, Haocheng Qin, Aiwu Lu, Meng Shi, Tiandao Li, Bo Zhang, Jianjun Guan, Cuicui Wang, Yousef Abu-Amer, Jie Shen
Abstract
The heterogeneity of cancer stem cells (CSCs) within tumors presents a challenge in therapeutic targeting. To decipher the cellular plasticity that fuels phenotypic heterogeneity, we undertook single-cell transcriptomics analysis in triple-negative breast cancer (TNBC) to identify subpopulations in CSCs. We found a subpopulation of CSCs with ancestral features that is marked by FXYD domain–containing ion transport regulator 3 (FXYD3), a component of the Na+/K+ pump. Accordingly, FXYD3+ CSCs evolve and proliferate, while displaying traits of alveolar progenitors that are normally induced during pregnancy. Clinically, FXYD3+ CSCs were persistent during neoadjuvant chemotherapy, hence linking them to drug-tolerant persisters (DTPs) and identifying them as crucial therapeutic targets. Importantly, FXYD3+ CSCs were sensitive to senolytic Na+/K+ pump inhibitors, such as cardiac glycosides. Together, our data indicate that FXYD3+ CSCs with ancestral features are drivers of plasticity and chemoresistance in TNBC. Targeting the Na+/K+ pump could be an effective strategy to eliminate CSCs with ancestral and DTP features that could improve TNBC prognosis.
Authors
Mengjiao Li, Tatsunori Nishimura, Yasuto Takeuchi, Tsunaki Hongu, Yuming Wang, Daisuke Shiokawa, Kang Wang, Haruka Hirose, Asako Sasahara, Masao Yano, Satoko Ishikawa, Masafumi Inokuchi, Tetsuo Ota, Masahiko Tanabe, Kei-ichiro Tada, Tetsu Akiyama, Xi Cheng, Chia-Chi Liu, Toshinari Yamashita, Sumio Sugano, Yutaro Uchida, Tomoki Chiba, Hiroshi Asahara, Masahiro Nakagawa, Shinya Sato, Yohei Miyagi, Teppei Shimamura, Luis Augusto E. Nagai, Akinori Kanai, Manami Katoh, Seitaro Nomura, Ryuichiro Nakato, Yutaka Suzuki, Arinobu Tojo, Dominic C. Voon, Seishi Ogawa, Koji Okamoto, Theodoros Foukakis, Noriko Gotoh
Abstract
In vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) are 2 major assisted reproductive techniques (ARTs) used widely to treat infertility. Recently, spermatogonial transplantation emerged as a new ART to restore fertility to young patients with cancer after cancer therapy. To examine the influence of germ cell manipulation on behavior of offspring, we produced F1 offspring by a combination of two ARTs, spermatogonial transplantation and ICSI. When these animals were compared with F1 offspring produced by ICSI using fresh wild-type sperm, not only spermatogonial transplantation–ICSI mice but also ICSI-only control mice exhibited behavioral abnormalities, which persisted in the F2 generation. Furthermore, although these F1 offspring appeared normal, F2 offspring produced by IVF using F1 sperm and wild-type oocytes showed various types of congenital abnormalities, including anophthalmia, hydrocephalus, and missing limbs. Therefore, ARTs can induce morphological and functional defects in mice, some of which become evident only after germline transmission.
Authors
Mito Kanatsu-Shinohara, Yusuke Shiromoto, Narumi Ogonuki, Kimiko Inoue, Satoko Hattori, Kento Miura, Naomi Watanabe, Ayumi Hasegawa, Keiji Mochida, Takuya Yamamoto, Tsuyoshi Miyakawa, Atsuo Ogura, Takashi Shinohara
Abstract
Reactivation and dysregulation of the mTOR signaling pathway is a hallmark of aging and chronic lung disease, however the impact on microvascular progenitor cells (MVPC), capillary angiostasis and tissue homeostasis is unknown. While the existence of an adult lung vascular progenitor has long been hypothesized, these studies show that Abcg2 enriches for a population of angiogenic tissue resident MVPC present in both adult mouse and human lungs using functional, lineage and transcriptomic analyses. These studies link human and mouse MVPC specific mTORC1 activation to decreased stemness, angiogenic potential, disruption of p53 and Wnt pathways, with consequent loss of alveolar-capillary structure and function. Following mTOR activation these MVPC adapt a unique transcriptome signature and emerge as a venous subpopulation in the angiodiverse microvascular endothelial subclusters. Thus, our findings support a significant role for mTOR in the maintenance of MVPC function, microvascular niche homeostasis as well as a cell-based mechanism driving loss of tissue structure underlying lung aging and the development of emphysema.
Authors
Emma C. Mason, Swapna Menon, Benjamin R. Schneider, Christa F. Gaskill, Maggie M. Dawson, Camille M. Moore, Laura Craig Armstrong, Okyong J. Cho, Bradley W. Richmond, Jonathan A. Kropski, James D. West, Patrick Geraghty, Brigitte N. Gomperts, Kevin C. Ess, Fabienne Gally, Susan M. Majka
Abstract
Human endogenous retroviruses (HERVs) are ancestral viral relics that constitute nearly 8% of the human genome. Although normally silenced, the most recently integrated provirus HERV-K (HML-2) can be reactivated in certain cancers. Here, we report pathological expression of HML-2 in malignant gliomas in both cerebrospinal fluid and tumor tissue that was associated with a cancer stem cell phenotype and poor outcomes. Using single-cell RNA-Seq, we identified glioblastoma cellular populations with elevated HML-2 transcripts in neural progenitor–like cells (NPC-like) that drive cellular plasticity. Using CRISPR interference, we demonstrate that HML-2 critically maintained glioblastoma stemness and tumorigenesis in both glioblastoma neurospheres and intracranial orthotopic murine models. Additionally, we demonstrate that HML-2 critically regulated embryonic stem cell programs in NPC-derived astroglia and altered their 3D cellular morphology by activating the nuclear transcription factor OCT4, which binds to an HML-2–specific long-terminal repeat (LTR5Hs). Moreover, we discovered that some glioblastoma cells formed immature retroviral virions, and inhibiting HML-2 expression with antiretroviral drugs reduced reverse transcriptase activity in the extracellular compartment, tumor viability, and pluripotency. Our results suggest that HML-2 fundamentally contributes to the glioblastoma stem cell niche. Because persistence of glioblastoma stem cells is considered responsible for treatment resistance and recurrence, HML-2 may serve as a unique therapeutic target.
Authors
Ashish H. Shah, Sarah R. Rivas, Tara T. Doucet-O’Hare, Vaidya Govindarajan, Catherine DeMarino, Tongguang Wang, Leonel Ampie, Yong Zhang, Yeshavanth Kumar Banasavadi-Siddegowda, Stuart Walbridge, Dragan Maric, Marta Garcia-Montojo, Robert K. Suter, Myoung-Hwa Lee, Kareem A. Zaghloul, Joseph Steiner, Abdel G. Elkahloun, Jay Chandar, Deepa Seetharam, Jelisah Desgraves, Wenxue Li, Kory Johnson, Michael E. Ivan, Ricardo J. Komotar, Mark R. Gilbert, John D. Heiss, Avindra Nath
Abstract
Acute graft-versus-host disease (aGVHD) is a severe complication of allogeneic hematopoietic stem cell transplantation. Hematopoietic dysfunction accompanied by severe aGVHD, which may be caused by niche impairment, is a long-standing clinical problem. However, how the bone marrow (BM) niche is damaged in aGVHD hosts is poorly defined. To comprehensively address this question, we employed a haplo-MHC-matched transplantation aGVHD murine model and performed single-cell RNA sequencing of non-hematopoietic BM cells. Transcriptional analysis showed that BM mesenchymal stromal cells (BMSCs) were severely affected with a reduction in cell ratio, abnormal metabolism, compromised differentiation potential and defective hematopoietic supportive function, which were validated by functional assays. We found that ruxolitinib, a selective JAK1/2 inhibitor, ameliorated aGVHD-related hematopoietic dysfunction through direct effect on recipient BMSCs, resulting in improved proliferation ability, adipogenesis/osteogenesis potential, mitochondrial metabolism capacity and crosstalk with donor-derived hematopoietic stem/progenitor cells. By inhibiting the JAK2/STAT1 pathway, ruxolitinib maintained long-term improvement of aGVHD BMSC function. Additionally, ruxolitinib pretreatment in vitro primed BMSCs to better support donor-derived hematopoiesis in vivo. These observations in the murine model were validated in patient samples. Overall, our findings suggest that ruxolitinib can directly restore BMSC function via JAK2/STAT1 pathway and in turn, improve the hematopoietic dysfunction caused by aGVHD.
Authors
Yan Lin, Quan Gu, Shihong Lu, Zengkai Pan, Zining Yang, Yapu Li, Shangda Yang, Yanling Lv, Zhaofeng Zheng, Guohuan Sun, Fanglin Gou, Chang Xu, Xiangnan Zhao, Fengjiao Wang, Chenchen Wang, Shiru Yuan, Xiaobao Xie, Yang Cao, Yue Liu, Weiying Gu, Tao Cheng, Hui Cheng, Xiaoxia Hu
Abstract
Multiple sclerosis (MS) is the most common chronic inflammatory disease of the central nervous system (CNS). The individual course is highly variable with complete remission in some patients and relentless courses in others. We generated induced pluripotent stem cells (iPSCs) to investigate possible mechanisms in benign MS (BMS), compared to progressive MS (PMS). We differentiated neurons and astrocytes that were then stressed with inflammatory cytokines typically associated with MS. TNFα/IL-17A treatment increased neurite damage in MS neurons irrespective of clinical phenotypes. In contrast, TNFα/IL-17A-reactive BMS astrocytes cultured with healthy control (HC) neurons exhibited significantly decreased axonal damage, compared to PMS astrocytes. Accordingly, single cell transcriptomic analysis of BMS-astrocyte co-cultured neurons demonstrated upregulated pathways of neuronal resilience, namely these astrocytes revealed differential growth factor expression. Moreover, supernatants from BMS astrocyte-neuron co-cultures rescued TNFα/IL-17-induced neurite damage. This process was associated with the unique expression of the growth factors, LIF and TGF-β1, as induced by TNFα/IL-17 and JAK-STAT activation. Our findings highlight a potential therapeutic role of modulating astrocyte phenotypes that generate a neuroprotective milieu preventing permanent neuronal damage.
Authors
Janis Kerkering, Bakhrom Muinjonov, Kamil Sebastian Rosiewicz, Sebastian Diecke, Charlotte Biese, Juliane Schiweck, Claudia Chien, Dario Zocholl, Thomas Conrad, Friedemann Paul, Marlen Alisch, Volker Siffrin
Copyright © 2026 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)