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Chronic myeloid leukemia (CML) stem cells have been identified to promote CML relapse due to their quiescent cell cycle and tyrosine kinase inhibitor resistance. Therefore, their eradication is important for the cure of CML. We herein identified the quiescent CML stem cell fraction using a G0 marker that can visualize quiescent cells. Whole-transcriptome analysis of imatinib-resistant, quiescent CML stem cells revealed that NF-κB is activated via inflammatory signals in the same cells. The combination of imatinib and an inhibitor of this inflammatory signal (IRAK1/4 inhibitor) effectively eliminated CML stem cells and attenuated PD-L1 expression in CML stem cells. Furthermore, the combination of anti-PD-L1 antibody and imatinib effectively eliminated CML stem cells in the presence of T-cell immunity, indicating the importance of creating an environment in which T cells can attack CML stem cells. Thus, IRAK1/4 inhibitors exert two effects: blocking CML stem cell survival and proliferation signals by inhibiting NF-κB and blocking T cell immune evasion by reducing PD-L1 expression in CML stem cells. Collectively, their combination may be one of the attractive strategies for achieving a radical cure for CML. Discussions regarding the possibility of future medications seem warranted.

Primary central nervous system lymphoma (PCNSL) is a rare extra-nodal non-Hodgkin's lymphoma confined to the central nervous system with a diffuse large B-cell lymphoma (DLBCL) histology and is highly prevelant in elderly patients. Whole brain radiotherapy (WBRT) does not provide considerable remission; rather it is highly involved in the development of leukoencephalopathy with delayed neurotoxicity, notably in elderly patients. Standard care for newly diagnosed patients with PCNSL comprised induction with high-dose methotrexate (HD-MTX)-based multi-agent immunochemotherapy, such as R-MPV (rituximab, MTX, procarbazine, vincristine) yielding 70-75% complete response rate, followed by HD-cytarabine consolidation. Consolidation high-dose chemotherapy with the key drug thiotepa supported by autologous stem cell transplant has recently been investigated to replace WBRT in multiple randomized trials, demonstrating non-inferiority to WBRT with less neurotoxicity. Comprehensive genetic analyses have revealed high rates of oncogenic mutations in CD79B and MYD88 genes, the hallmarks for MCD/C5 subtype of DLBCL, leading to constitutive activation of NF-κB signaling pathways in PCNSL. Bruton's tyrosine kinase (BTK), an intermediate kinase downstream to CD79B/MYD88, has emerged as a promising therapeutic target. Furthermore, tirabrutinib, a second-generation BTK inhibitor, has shown substantial activity against relapsed/refractory PCNSL, resulting in its approval in 2020 in Japan. Additionally, other new agents against PI3-kinase and immunotherapies including immunomodulatory agents, immune checkpoint blockade, and CAR-T have been actively tested in clinical trials.

Antiphospholipid syndrome (APS) is an autoimmune disorder defined by the presence of antiphospholipid antibodies in plasma of patients with vascular thrombosis and/or pregnancy morbidity. APS is considered the major cause of brain infarction in young adults and is a generally accepted cause of recurrent pregnancy loss. Antiphospholipid antibodies are a heterogeneous group of autoantibodies strongly related to the clinical manifestations of APS and with a widely recognized pathogenic role in thrombosis. In this article, recent clinical and pathophysiological advances in APS are discussed.

Amyotrophic lateral sclerosis (ALS) is a devastating disorder characterized by degeneration of motor neurons of the primary motor cortex, brainstem and spinal cord. ALS patients die within 3 to 5 years without respiratory support. Detecting the causing gene is necessary to elucidate ALS. We identified mutations of optineurin (OPTN) in ALS. We found three types of mutation of OPTN: a homozygous deletion of exon 5, a homozygous Q398X nonsense mutation and a heterozygous E478G missense mutation within its ubiquitin-binding domain. Cell transfection experiments showed that the nonsense and missense mutations of OPTN abolished the inhibition of activation of nuclear factor kappa B. The missense mutation revealed a cytoplasmic distribution different from that of the wild type. A case with the E478G mutation showed OPTN-immunoreactive cytoplasmic retention, and Golgi fragmentation was identified in 70% of the anterior horn cells. TDP-43- or SOD1-positive inclusions of sporadic and SOD1 cases of ALS were also immunolabelled with anti-OPTN antibodies. Furthermore, optineurin is co-localized with fused in sarcoma (FUS) in basophilic inclusions of ALS with FUS mutation and in basophilic inclusion body disease. Our findings suggest that OPTN is involved in the great part of pathogenesis of ALS.

High concordance rate in monozygotic twins and familial clustering of patients with primary biliary cirrhosis (PBC) indicate the involvement of strong genetic factors in the development of PBC. Recent genome-wide association studies (GWASs) and subsequent meta-analyses in European descent have identified HLA and 21 non-HLA susceptibility loci which are involved in IL12/IL12R signaling, TNF/TLR-NFKB signaling and B cell differentiation in the development of PBC. To identify susceptibility loci for PBC in Japanese population, a GWAS and subsequent replication study was performed in a total of 1327 PBC cases and 1120 healthy controls. In addition to the most significant susceptibility region at HLA, two significant (p<5×10(-8)) susceptibility loci (TNFSF15 and POU2AF1) were identified. Although these susceptibility loci are different from those identified in European descent (IL12A, IL12RB2, SPIB), these loci are involved in the same signaling pathways, differentiation of T lymphocyte to Th1 cells and differentiation of B lymphocyte to plasma cells. Among 21 non-HLA susceptibility loci for PBC identified in GWASs of European descent, 10 loci (CD80, IKZF3, IL7R, NFKB1, STAT4, TNFAIP2, CXCR5, MAP3K7IP1, rs6974491, DENND1B) showed significant associations in the Japanese population. The comparative analysis of disease-susceptibility genes in multiple ethnicities may provide an important clue for the dissection of disease-pathogenesis.

Immunity is based on self/nonself discrimination. In vertebrates, two major systems, innate and adaptive immune systems, constitute host defense against invading microbes. Adaptive immunity is characterized by specific immune responses through B- or T-cell antigen receptors that are generated by somatic recombination, whereas nonspecific responses to microbes had been accentuated in innate immunity. However, the discovery of pattern recognition receptors (PRRs) that are encoded in the germ-line, including Toll-like receptors, RIG-I-like receptors, NOD-like receptors and AIM2-like receptors, advanced our understanding of a mechanism for innate immune recognition. These types of PRR recognize pathogen- or damage-associated molecular patterns (PAMPs or DAMPs) during infection or tissue damage, and commonly evoke the downstream gene induction programme, such as expression of type I interferons, inflammatory cytokines and chemokines. Dysregulation of PRR-triggered signal activation leads to pathologic inflammatory responses. In this regard, it has been shown that many of "autoinflammatory diseases", recently defined clinical entity, have putatively causative mutations in the genes that encode PRRs or their signaling mediators. In this review article, we describe recent overview of PRRs as innate sensors and update knowledge of "autoinflammatory diseases" particularly by focusing on their association with innate signaling.

Nucleosides and nucleotides are one of the most important elements for cells by the fact that they are components of DNAs and RNAs. In addition, they play important roles in most fundamental cellular metabolic pathways such as energy donors, second messengers, and cofactors for various enzymes. Therefore, there exists a rich source in drug discovery targeting nucleosides and nucleotides. In order to utilize nucleosides and nucleic acids on the drug development, it is very important to develop reactions and methods, by which the highly coordinating and labile nucleoside intermediates can be used. With these in mind, we have been working on synthetic nucleoside and nucleic acid chemistry. First, branched sugar nucleoside derivatives, which are potential antitumor agents, have been synthesized utilizing samarium diiodide (SmI(2)) mediated Reformatsky reaction or aldol reaction. 3'-beta-Carbamoylmethylcytidine (CAMC) was found to exhibit potent cytotoxicity against various human tumor cell lines. Synthetic methodology of the caprazamycins, which are promising antibacterial nucleoside natural products, was also developed by the strategy including beta-selective ribosylation without using a neighboring group participation. Our synthetic route provided a range of key analogues with partial structures to define the pharmacophore. Simplification of the caprazamycins was further pursued to develop diketopiperazine analogs. Medicinal chemistry of oligodeoxynucleotides has been conducted. Thus, novel triazole-linked dumbbell oligodeoxynucleotides and modular bent oligodeoxynucleotides were synthesized. They exhibit excellent binding affinity to NF-kappaB or HMGB1 A-box protein, which are important therapeutic targets. Therefore, the results obtained conclusively demonstrated these oligodeoxynucleotides could be proposed as powerful decoy molecules.

Recent progress in cellular and molecular research has provided a new insight into the improvement of multiple organ dysfunction in sepsis. This paper introduces gene therapy targeting nuclear factor- kappaB, activator protein-1 and apoptosis of inflammatory alert cells in severe sepsis.

Chromium exists in many different oxidation states in the environment, Cr(VI) and Cr(III) being the most stable forms. Chromium has been known for over 100 years to be a human carcinogen. The greatest risk of cancer from chromium exposure is associated with Cr(VI). Cr(VI) enters cells via the sulfate anion transporter system and is reduced to intermediate oxidation states, such as Cr(V) and Cr(IV), in the process of forming stable Cr(III) forms. It is known that Cr(VI) affects expression of various genes. Metal responsive element-binding transcription factor-1 (MTF-1) is involved in sensing heavy metal load and the induced transcription of several protective genes, including metallothionein (MT)-I, MT-II, zinc transporter-1, and gamma-glutamylcysteine synthetase. Cr(VI) inhibits zinc-induced MT transcription via modifying transactivation potential of MTF-1. However, the molecular mechanism for the Cr(VI)-mediated inhibition of MTF-1 has not been fully elucidated. In this review, I briefly summarize the previous studies and discuss the current status of research on Cr(VI) toxicity and Cr(VI)-mediated inhibition against transcription.

Barrett's esophagus is the result of chronic injury which is usually caused by gastroesophageal reflux. NF-kappaB is expressed in the reflux esophagitis. Specialized columnar epithelium (SCE) is characteristic of Barrett's esophagus and has a malignant predisposition. SCE expresses Cdx1 and Cdx2. Adenocarcinoma in Barrett's esophagus is believed to develop through the metaplasia-dysplasia-carcinoma sequence. P53, beta-catenin, PPARgamma, and estrogen receptor beta are closely related to the development of esophageal carcinogenesis.