Vincristine is a widely used chemotherapeutic drug for the treatment of multiple malignant diseases that causes a dose-limiting peripheral neurotoxicity. There is no clinically effective preventative treatment for vincristine-induced sensory peripheral neurotoxicity (VIPN), and mechanistic details of this side effect remain poorly understood. We hypothesized that VIPN is dependent on transporter-mediated vincristine accumulation in dorsal root ganglion neurons. Using a xenobiotic transporter screen, we identified OATP1B3 as a neuronal transporter regulating the uptake of vincristine. In addition, genetic or pharmacological inhibition of the murine orthologue transporter OATP1B2 protected mice from various hallmarks of VIPN, including mechanical-induced allodynia, thermal hyperalgesia, and changes in digital maximal action potential amplitudes and neuronal morphology, without negatively affecting plasma levels or antitumor effects of vincristine. Finally, we identified α-tocopherol from an untargeted metabolomics analysis as a circulating endogenous biomarker of neuronal OATP1B2 function, which could serve as a future companion diagnostic to guide dose selection of OATP1B-type transport modulators given in combination with vincristine to prevent VIPN. Collectively, our findings shed light on the fundamental basis of VIPN and provide a rationale for the clinical development of transporter inhibitors to prevent this debilitating side effect.
Yang Li, Thomas Drabison, Mahesh Nepal, Richard H. Ho, Alix F. Leblanc, Alice A. Gibson, Yan Jin, Wenjian Yang, Kevin M. Huang, Muhammad Erfan Uddin, Mingqing Chen, Duncan F. DiGiacomo, Xihui Chen, Sobia Razzaq, Jeffrey R. Tonniges, Dana M. McTigue, Alice S. Mims, Maryam B. Lustberg, Yijia Wang, Amanda B. Hummon, William E. Evans, Sharyn D. Baker, Guido Cavaletti, Alex Sparreboom, Shuiying Hu
We previously reported that measles virus nucleocapsid protein (MVNP) expression in osteoclasts (OCLs) of Paget’s disease (PD) patients or targeted to the OCL lineage in transgenic (T-MVNP) mice increases IGF1 production in osteoclasts (OCL-IGF1) and develop PD-OCLs and pagetic bone lesions (PDLs). Conditional deletion of Igf1 in OCLs of T-MVNP mice fully blocked development of pagetic bone lesions (PDLs). In this manuscript we examined if osteocytes (OCys), key regulators of normal bone remodeling, contribute to PD. OCys in PDLs of patients and of T-MVNP mice expressed less sclerostin, and had increased RANKL expression compared to OCys in bones from WT mice or normal patients. To test if increased OCL-IGF1 is sufficient to induce PDLs and PD-phenotypes, we generated TRAP-Igf1 (T-Igf1) transgenic mice to characterize if increased IGF1 expression in the absence of MVNP in OCLs is sufficient to induce pagetic lesions and pagetic OCLs. We found that T-Igf1 mice at 16 months of age developed PD-OCLs, PDLs, and OCys with decreased sclerostin and increased RANKL similar to T-MVNP mice. Thus, pagetic phenotypes could be induced by OCLs expressing increased IGF1. OCL-IGF1 in turn increased RANKL production in OCys to induce PD-OCL and PDLs.
Kazuaki Miyagawa, Hirofumi Tenshin, Patrick L. Mulcrone, Jesus Delgado-Calle, Mark A. Subler, Jolene J. Windle, John M. Chirgwin, Garson David Roodman, Noriyoshi Kurihara
Antibodies capable of neutralising SARS-CoV-2 are well studied, but Fc receptor-dependent antibody activities that can also significantly impact the course of infection have not been studied in such depth. As most SARS-CoV-2 vaccines induce only anti-spike antibodies, here we investigated spike-specific antibody-dependent cellular cytotoxicity (ADCC). Vaccination produced antibodies that weakly induced ADCC, however, antibodies from individuals who were infected prior to vaccination (‘hybrid’ immunity) elicited strong anti-spike ADCC. Quantitative and qualitative aspects of humoral immunity contributed to this capability, with infection skewing IgG antibody production towards S2, vaccination skewing towards S1 and hybrid immunity evoking strong responses against both domains. Antibodies targeting both spike domains support strong antibody-dependent NK cell activation, with three regions of antibody reactivity outside the receptor-binding domain (RBD) corresponding with potent anti-spike ADCC. Consequently, ADCC induced by hybrid immunity with ancestral antigen was conserved against variants containing neutralisation escape mutations in the RBD. Induction of antibodies recognising a broad range of spike epitopes and eliciting strong and durable ADCC may partially explain why hybrid immunity provides superior protection against infection and disease than vaccination alone, and demonstrates that spike-only subunit vaccines would benefit from strategies that induce combined anti-S1 and S2 antibody responses.
Michael D. Grant, Kirsten Bentley, Ceri A. Fielding, Keeley M. Hatfield, Danielle P. Ings, Debbie Harnum, Eddie C.Y. Wang, Richard J. Stanton, Kayla A. Holder
Changes in neuronal activity modulate the vulnerability of motoneurons (MNs) in neurodegenerative diseases including amyotrophic lateral sclerosis (ALS). So far, the molecular basis of neuronal activity’s impact in ALS is poorly understood. Herein we investigated the impact of deleting the neuronal activity stimulated transcription factor (TF) serum response factor (SRF) in MNs of SOD1G93A mice. SRF was present in vulnerable MMP9 positive MNs. Ablation of SRF in MNs induced an earlier disease onset starting around 7-8 weeks after birth revealed by enhanced weight loss and decreased motor ability. This earlier disease onset in SRF depleted MNs was accompanied by mild elevation of neuroinflammation and neuromuscular synapse degeneration whereas overall MN numbers and mortality were unaffected. In SRF deficient mice, MNs showed impaired induction of autophagy encoding genes suggesting a new SRF function in transcriptional regulation of autophagy. Complementary, constitutive-active SRF-VP16 enhanced autophagy encoding gene transcription and autophagy progression in cells. Furthermore, SRF-VP16 decreased ALS-associated aggregate induction. Chemogenetic modulation of neuronal activity uncovered SRF as important TF mediating activity-dependent effects which might be beneficial to reduce ALS disease burden. Thus, our data identify with SRF a new gene regulator connecting neuronal activity with the cellular autophagy program initiated in degenerating MNs.
Jialei Song, Natalie Yashoda Dikwella, Daniela Sinske, Francesco Roselli, Bernd Knöll
Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disorder that causes debilitating swelling and destruction of the joints. People with RA are treated with drugs that actively suppress one or more parts of their immune system, and these may alter their response to vaccination against SARS-CoV-2. In this study, we analyzed blood samples from a cohort of RA subjects after receiving a 2-dose mRNA COVID-19 vaccine regimen. Our data show that individuals on the CTLA4-Ig therapy abatacept have reduced levels of SARS-CoV-2-neutralizing antibodies after vaccination. At a cellular level, these subjects show reduced activation and class-switching of SARS-CoV-2-specific B cells, as well as reduced numbers and impaired helper cytokine production by SARS-CoV-2-specific CD4+ T cells. Individuals on methotrexate showed similar but less severe defects in vaccine response, whereas individuals on the B cell-depleting therapy rituximab had a near-total loss of antibody production after vaccination. These data define a specific cellular phenotype associated with impaired response to SARS-CoV-2 vaccination in RA subjects on different immune-modifying therapies, and help inform efforts to improve vaccination strategies in this vulnerable population.
Samuel D Klebanoff, Lauren B. Rodda, Chihiro Morishima, Mark H. Wener, Yevgeniy Yuzefpolskiy, Estelle Bettelli, Jane H. Buckner, Cate Speake, Marion Pepper, Daniel J. Campbell
The RNA-binding protein LIN28B is overexpressed in over 30% of patients with colorectal cancer (CRC) and is associated with poor prognosis. In the present study, we unravel a novel mechanism by which LIN28B regulates colonic epithelial cell-cell junctions and CRC metastasis. Using human CRC cells (DLD-1, Caco-2 and LoVo) with either knockdown or overexpression of LIN28B, we identified Claudin 1 (CLDN1) tight junction protein as a direct downstream target and effector of LIN28B. RNA immunoprecipitation revealed that LIN28B directly binds to and post-transcriptionally regulates CLDN1 mRNA. Furthermore, using in vitro assays and a novel murine model of metastatic CRC, we show that LIN28B-mediated CLDN1 expression enhances collective invasion, cell migration, and metastatic liver tumor formation. Bulk RNA-sequencing of the metastatic liver tumors identified NOTCH3 as a downstream effector of the LIN28B-CLDN1 axis. Additionally, genetic and pharmacologic manipulation of NOTCH3 signaling revealed that NOTCH3 was necessary for invasion and metastatic liver tumor formation. In summary, our results suggest that LIN28B promotes invasion and liver metastasis of CRC by post-transcriptionally regulating CLDN1 and activating NOTCH3 signaling. This discovery offers a promising new therapeutic option for metastatic CRC to the liver, an area where therapeutic advancements have been relatively scarce.
Kensuke Sugiura, Yasunori Masuike, Kensuke Suzuki, Alice E. Shin, Nozomu Sakai, Hisahiro Matsubara, Masayuki Ohtsuka, Peter A. Sims, Christopher J. Lengner, Anil K. Rustgi
Influenza A virus (IAV) infection is commonly complicated by secondary bacterial infections, leading to increased morbidity and mortality. Our recent work demonstrates that IAV disrupts airway homeostasis, leading to airway pathophysiology resembling cystic fibrosis disease through diminished cystic fibrosis transmembrane conductance regulator (CFTR) function. Here, we use human airway organotypic cultures to investigate how IAV alters the airway microenvironment to increase susceptibility to secondary infection with Streptococcus pneumoniae (Spn). We observed that IAV-induced CFTR dysfunction and airway surface liquid acidification is central to increasing susceptibility to Spn. Additionally, we observed that IAV induced profound transcriptional changes in the airway epithelium and proteomic changes in the airway surface liquid in both CFTR dependent and independent manners. These changes correspond to multiple diminished host defense pathways and altered airway epithelial function. Collectively, these findings highlight both the importance of CFTR function during infectious challenge and demonstrate a central role for the lung epithelium in secondary bacterial infections following IAV.
Erin Y. Earnhardt, Jennifer L. Tipper, Adonis D'Mello, Ming-Yuan Jian, Elijah S. Conway, James A. Mobley, Carlos J. Orihuela, Hervé Tettelin, Kevin S. Harrod
Radiation therapy is an effective cancer treatment although damages to healthy tissues are common. Here we analyzed cell-free, methylated DNA released from dying cells into the circulation to evaluate radiation-induced cellular damages in different tissues. To map the circulating DNA fragments to human and mouse tissues, we established sequencing-based, cell-type specific reference DNA methylation atlases. We found that cell-type specific DNA blocks were mostly hypomethylated and located within signature genes of cellular identity. Cell-free DNA fragments were captured from serum samples by hybridization to CpG-rich DNA panels and mapped to the DNA methylation atlases. In a mouse model, thoracic radiation-induced tissue damages were reflected by dose-dependent increases in lung endothelial and cardiomyocyte methylated DNA in serum. The analysis of serum samples from breast cancer patients undergoing radiation treatment revealed distinct dose-dependent and tissue-specific epithelial and endothelial responses to radiation across multiple organs. Strikingly, patients treated for right-sided breast cancers also showed increased hepatocyte and liver endothelial DNA in the circulation indicating the impact on liver tissues. Thus, changes in cell-free methylated DNA can uncover cell-type specific effects of radiation and provide a readout of the biologically effective radiation dose received by healthy tissues.
Megan E. McNamara, Netanel Loyfer, Amber J. Kiliti, Marcel O. Schmidt, Sapir Shabi-Porat, Sidharth S. Jain, Sarah Martinez Roth, A. Patrick McDeed IV, Nesreen Shahrour, Elizabeth Ballew, Yun-Tien Lin, Heng-Hong Li, Anne Deslattes Mays, Sonali Rudra, Anna T. Riegel, Keith Unger, Tommy Kaplan, Anton Wellstein
Myotonic dystrophy type 1 (DM1), the most common form of adult-onset muscular dystrophy, is caused by a CTG expansion resulting in significant transcriptomic dysregulation that leads to muscle weakness and wasting. While strength training is clinically beneficial in DM1, molecular effects had not been studied. To determine whether training rescued transcriptomic defects, RNA-sequencing was performed on vastus lateralis samples from nine male DM1 patients before and after a 12-week strength training program and six male controls who did not undergo training. Differential gene expression and alternative splicing analysis were correlated with the one-repetition maximum strength evaluation method (leg extension, leg press, hip abduction, and squat). While training program-induced improvements in splicing were similar among most individuals, rescued splicing events varied considerably between individuals. Gene expression improvements were highly varied between individuals with the percentage of differentially expressed genes rescued after training strongly correlated with strength improvements. Evaluating transcriptome changes individually revealed responses to the training not evident from grouped analysis, likely due to disease heterogeneity and individual exercise response differences. Our analyses indicate that transcriptomic changes are associated with clinical outcomes in DM1 patients undergoing training and these changes are often specific to the individual and should be analyzed accordingly.
Emily E. Davey, Cécilia Légaré, Lori Planco, Sharon Shaughnessy, Claudia D. Lennon, Marie-Pier Roussel, Hannah K. Shorrock, Man Hung, John Douglas Cleary, Elise Duchesne, J. Andrew Berglund
The mineralocorticoid aldosterone, secreted by the adrenal zona glomerulosa (ZG), is critical for life, maintaining ion homeostasis and blood pressure. Therapeutic inhibition of protein phosphatase 3 (Calcineurin (Cn)) results in inappropriately low plasma aldosterone levels despite concomitant hyperkalemia and hyperreninemia. We tested the hypothesis that Cn participates in the signal transduction pathway regulating aldosterone synthesis. Inhibition of Cn with tacrolimus abolished the potassium (K+)-stimulated expression of aldosterone synthase, encoded by CYP11B2, in the NCI-H295R human adrenocortical cell line as well as ex vivo in mouse and human adrenal tissue. ZG-specific deletion of the regulatory Cn subunit CnB1 diminished Cyp11b2 expression in vivo and disrupted K+-mediated aldosterone synthesis. Phosphoproteomic analysis identified Nuclear factor of activated T-cells, cytoplasmic 4 (NFATc4) as a target for Cn-mediated dephosphorylation. Deletion of NFATc4 impaired K+-dependent stimulation of CYP11B2 expression and aldosterone production while expression of a constitutively active form of NFATc4 increased expression of CYP11B2 in NCI-H295R cells. Chromatin immunoprecipitation revealed NFATc4 directly regulates CYP11B2 expression. Thus, calcineurin controls aldosterone production via the Cn-NFATc4 pathway. Inhibition of Cn-NFATc4 signaling may explain low plasma aldosterone levels and hyperkalemia in patients treated with tacrolimus and the Cn-NFATc4 pathway may provide novel molecular targets to treat primary aldosteronism.
Mesut Berber, Sining Leng, Agnieszka Wengi, Denise V. Winter, Alex Odermatt, Felix Beuschlein, Johannes Loffing, David T. Breault, David Penton
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