CD71 erythroid cells promote multiple myeloma progression and impair anti-bacterial immune response.

Multiple myeloma (MM), one of the most frequent haematological malignancies, significantly increases the risk of bacterial infections due to treatment-related side effects, comorbidities and cancer-induced immune deficiencies. Recently, CD71 erythroid cells (CECs) have been identified as key immunomodulators in neonates and cancer patients, but their role in MM progression remains unclear. Using a murine MM model, closely resembling human disease, we observed that MM progression is associated with anaemia and an increase in immature CECs, which are characterized by elevated arginase 2 (ARG2) expression.

p66Shc Protein-Oxidative Stress Sensor or Redox Enzyme: Its Potential Role in Mitochondrial Metabolism of Human Breast Cancer.

This work presents a comprehensive evaluation of the role of p66Shc protein in mitochondrial physiology in MDA-MB-231 breast cancer cells. The use of human breast cancer cell line MDA-MB-231 and its genetically modified clones (obtained with the use of the CRISPR-Cas9 technique), expressing different levels of p66Shc protein, allowed us to demonstrate how the p66Shc protein affects mitochondrial metabolism of human breast cancer cells. Changes in the level of p66Shc (its overexpression, and overexpressing of its Serine 36-mutated version, as well as the knockout of p66Shc) exert different effects in breast cancer cells.

SARS-CoV-2 and its ORF3a, E and M viroporins activate inflammasome in human macrophages and induce of IL-1α in pulmonary epithelial and endothelial cells.

Inflammasome assembly is a potent mechanism responsible for the host protection against pathogens, including viruses. When compromised, it can allow viral replication, while when disrupted, it can perpetuate pathological responses by IL-1 signaling and pyroptotic cell death. SARS-CoV-2 infection was shown to activate inflammasome in the lungs of COVID-19 patients, however, potential mechanisms responsible for this response are not fully elucidated.

Trinucleotide mRNA Cap Analogue 6-Benzylated at the Site of Posttranscriptional A Mark Facilitates mRNA Purification and Confers Superior Translational Properties In Vitro and In Vivo.

Eukaryotic mRNAs undergo cotranscriptional 5'-end modification with a 7-methylguanosine cap. In higher eukaryotes, the cap carries additional methylations, such as A─a common epitranscriptomic mark unique to the mRNA 5'-end. This modification is regulated by the Pcif1 methyltransferase and the FTO demethylase, but its biological function is still unknown.

lncRNA DIRC3 regulates invasiveness and insulin-like growth factor signaling in thyroid cancer cells.

Differentiated thyroid cancers (DTCs) are malignancies that demonstrate strong but largely uncharacterized heritability. Germline variants that influence the risk of DTCs localize in disrupted in renal carcinoma 3 (DIRC3), a poorly described long non-coding RNA gene. Here, we investigated the function of DIRC3 in DTCs.

Arginase Inhibition Mitigates Bortezomib-Exacerbated Cardiotoxicity in Multiple Myeloma.

Background: Multiple myeloma (MM) is associated with increased cardiovascular morbidity and mortality, while MM therapies also result in adverse cardiac effects. Endothelial dysfunction and impaired nitric oxide (NO) pathway is their possible mediator.

Objective: Since MM is associated with increased arginase expression, resulting in the consumption of ʟ-arginine, precursor for NO synthesis, our aim was to test if cardiotoxicity mediated by MM and MM therapeutic, bortezomib (a proteasome inhibitor), can be ameliorated by an arginase inhibitor through improved endothelial function.

The potential of PARP inhibitors in targeted cancer therapy and immunotherapy.

DNA damage response (DDR) deficiencies result in genome instability, which is one of the hallmarks of cancer. Poly (ADP-ribose) polymerase (PARP) enzymes take part in various DDR pathways, determining cell fate in the wake of DNA damage. PARPs are readily druggable and PARP inhibitors (PARPi) against the main DDR-associated PARPs, PARP1 and PARP2, are currently approved for the treatment of a range of tumor types.

Targeting arginase-1 exerts antitumor effects in multiple myeloma and mitigates bortezomib-induced cardiotoxicity.

Multiple myeloma (MM) remains an incurable malignancy of plasma cells despite constantly evolving therapeutic approaches including various types of immunotherapy. Increased arginase activity has been associated with potent suppression of T-cell immune responses in different types of cancer. Here, we investigated the role of arginase 1 (ARG1) in Vκ*MYC model of MM in mice.

Immune checkpoint inhibition improves antimyeloma activity of bortezomib and STING agonist combination in Vk*MYC preclinical model.

Unlabelled: Multiple myeloma (MM), a hematological malignancy of plasma cells, has remained incurable despite the development of novel therapies that improve patients' outcome. Recent evidence indicates that the stimulator of interferon genes (STING) pathway may represent a novel target for induction of antitumor immune response in multiple myeloma. Here, we investigated antitumor effects of STING agonist with bortezomib with or without checkpoint inhibitor in the treatment of MM.

Ablation of Gene Impairs Erythropoiesis in Mice.

(1) Background: Transcriptomic and proteomic studies provide a wealth of new genes potentially involved in red blood cell (RBC) maturation or implicated in the pathogenesis of anemias, necessitating validation of candidate genes in vivo; (2) Methods: We inactivated one such candidate, transmembrane and coiled-coil domain 2 () in mice, and analyzed the erythropoietic phenotype by light microscopy, transmission electron microscopy (TEM), and flow cytometry of erythrocytes and erythroid precursors; (3) Results: pups presented pallor and reduced body weight due to the profound neonatal macrocytic anemia with numerous nucleated RBCs (nRBCs) and occasional multinucleated RBCs. nRBCs had cytoplasmic intrusions into the nucleus and double membranes. Significantly fewer erythroid cells were enucleated.

Potent but transient immunosuppression of T-cells is a general feature of CD71 erythroid cells.

CD71 erythroid cells (CECs) have been recently recognized in both neonates and cancer patients as potent immunoregulatory cells. Here, we show that in mice early-stage CECs expand in anemia, have high levels of arginase 2 (ARG2) and reactive oxygen species (ROS). In the spleens of anemic mice, CECs expansion-induced -arginine depletion suppresses T-cell responses.

MLK4 regulates DNA damage response and promotes triple-negative breast cancer chemoresistance.

Chemoresistance constitutes a major challenge in the treatment of triple-negative breast cancer (TNBC). Mixed-Lineage Kinase 4 (MLK4) is frequently amplified or overexpressed in TNBC where it facilitates the aggressive growth and migratory potential of breast cancer cells. However, the functional role of MLK4 in resistance to chemotherapy has not been investigated so far.

Inhibition of PIM Kinases in DLBCL Targets MYC Transcriptional Program and Augments the Efficacy of Anti-CD20 Antibodies.

The family of PIM serine/threonine kinases includes three highly conserved oncogenes, and , which regulate multiple prosurvival pathways and cooperate with other oncogenes such as . Recent genomic CRISPR-Cas9 screens further highlighted oncogenic functions of PIMs in diffuse large B-cell lymphoma (DLBCL) cells, justifying the development of small-molecule PIM inhibitors and therapeutic targeting of PIM kinases in lymphomas. However, detailed consequences of PIM inhibition in DLBCL remain undefined.

Inhibition of arginase modulates T-cell response in the tumor microenvironment of lung carcinoma.

Immunotherapy has demonstrated significant activity in a broad range of cancer types, but still the majority of patients receiving it do not maintain durable therapeutic responses. Amino acid metabolism has been proposed to be involved in the regulation of immune response. Here, we investigated in detail the role of arginase 1 (Arg1) in the modulation of antitumor immune response against poorly immunogenic Lewis lung carcinoma.

The role of CD71 erythroid cells in the regulation of the immune response.

Complex regulation of the immune response is necessary to support effective defense of an organism against hostile invaders and to maintain tolerance to harmless microorganisms and autoantigens. Recent studies revealed previously unappreciated roles of CD71 erythroid cells (CECs) in regulation of the immune response. CECs physiologically reside in the bone marrow where erythropoiesis takes place.

Inhibition of the ʟ-glutamine transporter ASCT2 sensitizes plasma cell myeloma cells to proteasome inhibitors.

Proteasome inhibitors (PIs), used in the treatment of plasma cell myeloma (PCM), interfere with the degradation of misfolded proteins leading to activation of unfolded protein response (UPR) and cell death. However, despite initial strong antimyeloma effects, PCM cells eventually develop acquired resistance to PIs. The pleiotropic role of ʟ-glutamine (Gln) in cellular functions makes inhibition of Gln metabolism a potentially good candidate for combination therapy.

Tumor Immune Evasion Induced by Dysregulation of Erythroid Progenitor Cells Development.

Cancer cells harness normal cells to facilitate tumor growth and metastasis. Within this complex network of interactions, the establishment and maintenance of immune evasion mechanisms are crucial for cancer progression. The escape from the immune surveillance results from multiple independent mechanisms.

Mosaic IL6ST variant inducing constitutive GP130 cytokine receptor signaling as a cause of neonatal onset immunodeficiency with autoinflammation and dysmorphy.

Interleukin-6 signal transducer (IL6ST) encodes the GP130 protein which transduces the proinflammatory signaling of the IL6 cytokine family through Janus kinase signal transducers and activators of transcription pathway (JAK/STAT) activation. Biallelic loss-of-function IL6ST variants cause autosomal recessive hyper-IgE syndrome or a variant of the Stuve-Wiedemann syndrome. Somatic gain-of-function IL6ST mutations, in particular, small monoallelic in-frame deletions of which the most prevalent is the IL6ST Ser187_Tyr190del, are an established cause of inflammatory hepatocellular tumors, but so far, no disease caused by such mutations present constitutively has been described.

Transport of nanoprobes in multicellular spheroids.

The efficient delivery of drugs to cells depends on their diffusion through the extracellular matrix (ECM) of tissues. Here we present a study on the diffusion of nanoprobes of radius from 1 nm to over 100 nm in the ECM of spheroids of three cell types (HeLa, MCF-7 and fibroblasts). We quantified the nanoparticle transport in the spheroids' proliferating zone.