Regenerative medicine aims to replace the lost or damaged cells in the human body through a new source of healthy transplanted cells or by endogenous repair. Although human embryonic stem cells were ...first thought to be the ideal source for cell therapy and tissue repair in humans, the discovery by Yamanaka and colleagues revolutionized the field. Almost any differentiated cell can be sent back in time to a pluripotency state by expressing the appropriate transcription factors. The process of somatic reprogramming using Yamanaka factors, many of which are oncogenes, offers a glimpse into how cancer stem cells may originate. In this review we discuss the similarities between tumor dedifferentiation and somatic cell reprogramming and how this may pose a risk to the application of this new technology in regenerative medicine.
Research in the reprogramming of somatic cells has also led to a better understanding of the origin of cancer stem cells. This review discusses cancers that may be the product of somatic cell reprogramming and as such constitute potential risks to the application of iPSCs in regenerative medicine.
Quantifying gross primary production (GPP) remains a major challenge in global carbon cycle research. Spaceborne monitoring of solar-induced chlorophyll fluorescence (SIF), an integrative ...photosynthetic signal of molecular origin, can assist in terrestrial GPP monitoring. However, the extent to which SIF tracks spatiotemporal variations in GPP remains unresolved. Orbiting Carbon Observatory-2 (OCO-2)'s SIF data acquisition and fine spatial resolution permit direct validation against ground and airborne observations. Empirical orthogonal function analysis shows consistent spatiotemporal correspondence between OCO-2 SIF and GPP globally. A linear SIF-GPP relationship is also obtained at eddy-flux sites covering diverse biomes, setting the stage for future investigations of the robustness of such a relationship across more biomes. Our findings support the central importance of high-quality satellite SIF for studying terrestrial carbon cycle dynamics.
The circadian clock imposes daily rhythms in cell proliferation, metabolism, inflammation and DNA damage response. Perturbations of these processes are hallmarks of cancer and chronic circadian ...rhythm disruption predisposes individuals to tumour development. This raises the hypothesis that pharmacological modulation of the circadian machinery may be an effective therapeutic strategy for combating cancer. REV-ERBs, the nuclear hormone receptors REV-ERBα (also known as NR1D1) and REV-ERBβ (also known as NR1D2), are essential components of the circadian clock. Here we show that two agonists of REV-ERBs-SR9009 and SR9011-are specifically lethal to cancer cells and oncogene-induced senescent cells, including melanocytic naevi, and have no effect on the viability of normal cells or tissues. The anticancer activity of SR9009 and SR9011 affects a number of oncogenic drivers (such as HRAS, BRAF, PIK3CA and others) and persists in the absence of p53 and under hypoxic conditions. The regulation of autophagy and de novo lipogenesis by SR9009 and SR9011 has a critical role in evoking an apoptotic response in malignant cells. Notably, the selective anticancer properties of these REV-ERB agonists impair glioblastoma growth in vivo and improve survival without causing overt toxicity in mice. These results indicate that pharmacological modulation of circadian regulators is an effective antitumour strategy, identifying a class of anticancer agents with a wide therapeutic window. We propose that REV-ERB agonists are inhibitors of autophagy and de novo lipogenesis, with selective activity towards malignant and benign neoplasms.
Mitophagy is critical for cell homeostasis. Externalization of the inner mitochondrial membrane phospholipid, cardiolipin (CL), to the surface of the outer mitochondrial membrane (OMM) was identified ...as a mitophageal signal recognized by the microtubule-associated protein 1 light chain 3. However, the CL-translocating machinery remains unknown. Here we demonstrate that a hexameric intermembrane space protein, NDPK-D (or NM23-H4), binds CL and facilitates its redistribution to the OMM. We found that mitophagy induced by a protonophoric uncoupler, carbonyl cyanide m-chlorophenylhydrazone (CCCP), caused externalization of CL to the surface of mitochondria in murine lung epithelial MLE-12 cells and human cervical adenocarcinoma HeLa cells. RNAi knockdown of endogenous NDPK-D decreased CCCP-induced CL externalization and mitochondrial degradation. A R90D NDPK-D mutant that does not bind CL was inactive in promoting mitophagy. Similarly, rotenone and 6-hydroxydopamine triggered mitophagy in SH-SY5Y cells was also suppressed by knocking down of NDPK-D. In situ proximity ligation assay (PLA) showed that mitophagy-inducing CL-transfer activity of NDPK-D is closely associated with the dynamin-like GTPase OPA1, implicating fission-fusion dynamics in mitophagy regulation.
In keeping with the growing movement in scientific publishing toward transparency in data and methods, we propose changes to journal authorship policies and procedures to provide insight into which ...author is responsible for which contributions, better assurance that the list is complete, and clearly articulated standards to justify earning authorship credit. To accomplish these goals, we recommend that journals adopt common and transparent standards for authorship, outline responsibilities for corresponding authors, adopt the Contributor Roles Taxonomy (CRediT) (docs.casrai.org/CRediT) methodology for attributing contributions, include this information in article metadata, and require authors to use the ORCID persistent digital identifier (https://orcid.org). Additionally, we recommend that universities and research institutions articulate expectations about author roles and responsibilities to provide a point of common understanding for discussion of authorship across research teams. Furthermore, we propose that funding agencies adopt the ORCID identifier and accept the CRediT taxonomy. We encourage scientific societies to further authorship transparency by signing on to these recommendations and promoting them through their meetings and publications programs.
Lung disease is a major cause of death in the United States, with current therapeutic approaches serving only to manage symptoms. The most common chronic and life-threatening genetic disease of the ...lung is cystic fibrosis (CF) caused by mutations in the cystic fibrosis transmembrane regulator (CFTR). We have generated induced pluripotent stem cells (iPSCs) from CF patients carrying a homozygous deletion of F508 in the CFTR gene, which results in defective processing of CFTR to the cell membrane. This mutation was precisely corrected using CRISPR to target corrective sequences to the endogenous CFTR genomic locus, in combination with a completely excisable selection system, which significantly improved the efficiency of this correction. The corrected iPSCs were subsequently differentiated to mature airway epithelial cells where recovery of normal CFTR expression and function was demonstrated. This isogenic iPSC-based model system for CF could be adapted for the development of new therapeutic approaches.
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•Generation of iPSCs from a CF patient homozygous for the common ΔF508 CFTR mutation•CRISPR-based targeting of corrective sequences to endogenous CFTR gene in CF iPSCs•Complete, efficient excision of selection markers by pBac transposase•Differentiation to lung epithelial cells demonstrating functional correction of CFTR
Firth et al. describe a robust in vitro human cellular model of CF with great therapeutic potential. A combination of CRISPR and pBac transposase technology allowed for efficient, footprint-free gene correction in CF iPSCs. Lung epithelial cells subsequently derived from corrected iPSCs demonstrated recovered function and expression of CFTR.
The mesenchymal subtype of glioblastoma is thought to be determined by both cancer cell-intrinsic alterations and extrinsic cellular interactions, but remains poorly understood. Here, we dissect ...glioblastoma-to-microenvironment interactions by single-cell RNA sequencing analysis of human tumors and model systems, combined with functional experiments. We demonstrate that macrophages induce a transition of glioblastoma cells into mesenchymal-like (MES-like) states. This effect is mediated, both in vitro and in vivo, by macrophage-derived oncostatin M (OSM) that interacts with its receptors (OSMR or LIFR) in complex with GP130 on glioblastoma cells and activates STAT3. We show that MES-like glioblastoma states are also associated with increased expression of a mesenchymal program in macrophages and with increased cytotoxicity of T cells, highlighting extensive alterations of the immune microenvironment with potential therapeutic implications.
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•Macrophages induce the MES-like state of glioblastoma cells•Induction is mediated by macrophage-derived OSM interacting with OSMR/LIFR-GP130•Subsets of glioblastoma-associated macrophages express a related MES-like program•The MES-like state in glioblastoma is associated with cytotoxic T cells programs
Hara et al. combine single-cell RNA sequencing and functional experiments to explore the crosstalk between glioblastoma and the microenvironment, revealing that macrophage-derived OSM induces the mesenchymal-like state of glioblastoma, a state associated with upregulation of major histocompatibility complex genes, and with potential implications for immunotherapy.
Safe and efficient delivery of messenger RNAs for protein replacement therapies offers great promise but remains challenging. In this report, we demonstrate systemic, in vivo, nonviral mRNA delivery ...through lipid nanoparticles (LNPs) to treat a Factor IX (FIX)-deficient mouse model of hemophilia B. Delivery of human FIX (hFIX)mRNA encapsulated in our LUNAR LNPs results in a rapid pulse of FIX protein (within 4–6 h) that remains stable for up to 4–6 d and is therapeutically effective, like the recombinant human factor IX protein (rhFIX) that is the current standard of care. Extensive cytokine and liver enzyme profiling showed that repeated administration of the mRNA–LUNAR complex does not cause any adverse innate or adaptive immune responses in immune-competent, hemophilic mice. The levels of hFIX protein that were produced also remained consistent during repeated administrations. These results suggest that delivery of long mRNAs is a viable therapeutic alternative for many clotting disorders and for other hepatic diseases where recombinant proteins may be unaffordable or unsuitable.
Many types of human tumor cells have overexpressed pyruvate kinase M2 (PKM2). However, the mechanism underlying this increased PKM2 expression remains to be defined. We demonstrate here that EGFR ...activation induces PLCγ1-dependent PKCε monoubiquitylation at Lys321 mediated by RINCK1 ubiquitin ligase. Monoubiquitylated PKCε interacts with a ubiquitin-binding domain in NEMO zinc finger and recruits the cytosolic IKK complex to the plasma membrane, where PKCε phosphorylates IKKβ at Ser177 and activates IKKβ. Activated RelA interacts with HIF1α, which is required for RelA to bind the PKM promoter. PKCε- and NF-κB-dependent PKM2 upregulation is required for EGFR-promoted glycolysis and tumorigenesis. In addition, PKM2 expression correlates with EGFR and IKKβ activity in human glioblastoma specimens and with grade of glioma malignancy. These findings highlight the distinct regulation of NF-κB by EGF, in contrast to TNF-α, and the importance of the metabolic cooperation between the EGFR and NF-κB pathways in PKM2 upregulation and tumorigenesis.
► NF-κB is required for EGFR-induced transcriptional upregulation of PKM2 ► Monoubiquitylated PKCε recruits IKK complex ► PKCε phosphorylates IKKβ at Ser177 and activates IKKβ ► PKM2 upregulation is required for EGFR-promoted glycolysis and tumorigenesis
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