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Background: Upper tract urothelial carcinoma (UTUC) is a rare tumor with extraordinarily different features between Eastern and Western countries. Vascular endothelial growth factor‐A (VEGFA) was originally identified as a secreted signaling protein and regulator of vascular development and cancer progression. In this study, we aimed to elucidate the molecular mechanisms underlying the regulation of VEGFA by microRNA in UTUC. Methods: VEGFA expression was evaluated by immunohistochemistry in 140 human UTUC tissue samples. Next, we assessed the regulatory relationship between VEGFA and miR‐299‐3p by real‐time PCR, western blotting, ELISA and dual‐luciferase reporter assays using two UTUC cell lines. The role of miR‐299‐3p/VEGFA in cell proliferation, motility, invasion, and tube formation was analyzed in vitro. Results: High VEGFA expression was significantly associated with tumor stage, grade, distant metastasis and cancer‐related death and correlated with poor progression‐free and cancer‐specific survival. VEGFA knockdown repressed proliferation, migration, invasion and angiogenesis in UTUC cell lines. miR‐299‐3p significantly reduced VEGFA protein expression and miR‐299‐3p overexpression inhibited VEGFA mRNA and protein expression by directly targeting its 3′‐UTR. Functional studies indicated that VEGFA overexpression reversed the miR‐299‐3p‐mediated suppression of tumor cell proliferation, migration, invasion and angiogenesis. In addition, miR‐299‐3p/VEGFA suppressed cellular functions in UTUC by modulating the expression of P18 and cyclin E2. Conclusions: Our findings suggest that miR‐299‐3p possibly suppresses UTUC cell proliferation, motility, invasion and angiogenesis via VEGFA. VEGFA may act as a prognostic predictor, and both VEGFA and miR‐299‐3p could be potential therapeutic targets for UTUC. [ABSTRACT FROM AUTHOR]

Polyglutamine (polyQ)-mediated spinocerebellar ataxia (SCA), including SCA1, 2, 3, 6, 7, and 17, are caused by mutant genes with expanded CAG repeats, leading to the intracellular accumulation of aggregated proteins, the production of reactive oxygen species, and cell death. Among SCA, SCA3 is caused by a mutation in the ATXN3 (ataxin-3) gene. In a circumstance of polyQ aggregation, the autophagic pathway is induced to degrade the aggregated proteins, thereby suppressing downstream deleterious effects and promoting neuronal survival. In this study, we tested the effects of synthetic indole (NC009-1, -2, -3, -6) and coumarin (LM-022, -031) derivatives as chemical chaperones to assist mutant ATXN3-Q75 folding, as well as autophagy inducers to clear aggregated protein. Among the tested compounds, NC009-1, -2, and -6 and LM-031 interfered with Escherichia coli-derived ATXN3-Q75 aggregation in thioflavin T binding and filter trap assays. In SH-SY5Y cells expressing GFP-fused ATXN3-Q75, these compounds displayed aggregation-inhibitory and neurite growth-promoting potentials compared to untreated cells. Furthermore, these compounds activated autophagy by increasing the phosphatidylethanolamine-conjugated LC3 (microtubule associated protein 1 light chain 3)-II:cytosolic LC3-I ratio in these cells. A biochemical co-immunoprecipitation assay by using a mixture of HEK 293T cell lysates containing recombinant ATXN3-Q75-Venus-C-terminus (VC) or Venus-N-terminus (VN)-LC3 protein indicated that NC009-1 and -2 and LM-031 served as an autophagosome-tethering compound (ATTEC) to interact with ATXN3-Q75 and LC3, and the interaction was further confirmed by bimolecular fluorescence complementation analysis in cells co-expressing both ATXN3-Q75-VC and VN-LC3 proteins. The study results suggest the potential of NC009-1 and -2 and LM-031 as an ATTEC in treating SCA3 and, probably, other polyQ diseases. [ABSTRACT FROM AUTHOR]

DUSP22 is a dual-specificity phosphatase that inhibits T cell activation by inactivating the kinase Lck. Here we show that the E3 ubiquitin ligase UBR2 is a positive upstream regulator of Lck during T-cell activation. DUSP22 dephosphorylates UBR2 at specific Serine residues, leading to ubiquitin-mediated UBR2 degradation. UBR2 is also modified by the SCF E3 ubiquitin ligase complex via Lys48-linked ubiquitination at multiple Lysine residues. Single-cell RNA sequencing analysis and UBR2 loss of function experiments showed that UBR2 is a positive regulator of proinflammatory cytokine expression. Mechanistically, UBR2 induces Lys63-linked ubiquitination of Lck at Lys99 and Lys276 residues, followed by Lck Tyr394 phosphorylation and activation as part of TCR signalling. Inflammatory phenotypes induced by TCR-triggered Lck activation or knocking out DUSP22, are attenuated by genomic deletion of UBR2. UBR2-Lck interaction and Lck Lys63-linked ubiquitination are induced in the peripheral blood T cells of human SLE patients, which demonstrate the relevance of the UBR2-mediated regulation of inflammation to human pathology. In summary, we show here an important regulatory mechanism of T cell activation, which finetunes the balance between T cell response and aggravated inflammation. The T cell receptor signalosome integrates multiple positive and negative regulatory elements to finetune the response and limit harmful inflammation. Here authors show a regulatory cascade of T cell activation, in which DUSP22 negatively regulates UBR2, which is an activator of the kinase Lck via K63 ubiquitination. [ABSTRACT FROM AUTHOR]

Background: The aim of the study was investigate the impact of body-mass factors (BMF) on setup displacement during pelvic radiotherapy in patients with lower abdominal cancers. Patients and methods: The clinical data of a training cohort composed of 60 patients with gynecological, rectal, or prostate cancer were analyzed. The daily alignment data from image-guided radiotherapy (IGRT) were retrieved. Setup errors for were assessed by systematic error (SE) and random error (RE) through the superior-inferior (SI), anterior-posterior (AP), and medial-lateral (ML) directions. Several BMFs and patient-related parameters were analyzed with binary logistic regression and receiver-operating characteristic curves. A scoring system was proposed to identify those with greater setup displacement during daily treatment. The results were validated by another cohort. Results: A large hip lateral diameter correlated with a greater SI-SE and AP-SE, whereas a large umbilical AP diameter correlated with a greater ML-SE and ML-RE. A higher SI-RE was associated with a large hip circumference. The positive predictors for setup uncertainty were chosen to dichotomize patients into groups at high risk and low risk for setup displacement. Based on the scoring system, the adequate treatment margins for the SI direction in the high-and low-risk groups were 5.4 mm and 3.8 mm, whereas those for the ML direction were 8.2 mm and 4.2 mm, respectively. The validated cohort showed a similar trend. Conclusions: Large BMFs including hip lateral diameter, hip circumference, and umbilical AP diameter are associated with greater setup uncertainty. Based on the scores, IGRT or required treatment margins can be adapted for patients with high risk features. [ABSTRACT FROM AUTHOR]

Gemcitabine-based chemotherapy is the current standard treatment for biliary tract cancers (BTCs) and resistance to gemcitabine remains the clinical challenge. TP53 mutation has been shown to be associated with poor clinicopathologic characteristics and survival in patients with BTCs, indicating that p53 plays an important role in the treatment of these cancers. Herein, we comprehensively reviewed previous BTC preclinical research and early clinical trials in terms of p53, as well as novel p53-targeted treatment, alone or in combination with either chemotherapy or other targeted therapies in BTCs. Preclinical studies have demonstrated that p53 mutations in BTCs are associated with enhanced gemcitabine resistance, therefore targeting p53 may be a novel therapeutic strategy for treatment of BTCs. Directly targeting mutant p53 by p53 activators, or indirectly by targeting cell cycle checkpoint proteins (Chk1, ataxia telangiectasia related (ATR), and Wee1) leading to synthetic lethality, may be potential future strategies for gemcitabine-resistant p53 mutated BTCs. In contrast, for wild-type p53 BTCs, activation of p53 by inhibition of its negative regulators (MDM2 and wild-type p53-induced phosphatase 1 (WIP1)) may be alternative options. Combination therapies consisting of standard cytotoxic drugs and novel small molecules targeting p53 and related signaling pathways may be the future key standard approach to beat cancer. [ABSTRACT FROM AUTHOR]

This study investigated the effects of a single dose of arginine (Arg) administration at the beginning of sepsis on CD4+ T-cell regulation and liver inflammation in C57BL/6J mice. Mice were divided into normal control (NC), sham (SH), sepsis saline (SS), and sepsis Arg (SA) groups. An inducible nitric oxide (NO) synthase (iNOS) inhibitor was administered to additional sepsis groups to evaluate the role of NO during sepsis. Sepsis was induced using cecal ligation and puncture (CLP). The SS and SA groups received saline or Arg (300 mg/kg body weight) via tail vein 1 h after CLP. Mice were euthanized at 12 and 24 h post-CLP. Blood, para-aortic lymph nodes, and liver tissues were collected for further measurement. The findings showed that sepsis resulted in decreases in blood and para-aortic lymph node CD4+ T-cell percentages, whereas percentages of interleukin (IL)-4- and IL-17-expressing CD4+ T cells were upregulated. Compared to the SS group, Arg administration resulted in maintained circulating and para-aortic lymph node CD4+ T cells, an increased Th1/Th2 ratio, and a reduced Th17/Treg ratio post-CLP. In addition, levels of plasma liver injury markers and expression of inflammatory genes in liver decreased. These results suggest that a single dose of Arg administered after CLP increased Arg availability, sustained CD4+ T-cell populations, elicited more-balanced Th1/Th2/Th17/Treg polarization in the circulation and the para-aortic lymph nodes, and attenuated liver inflammation in sepsis. The favorable effects of Arg were abrogated when an iNOS inhibitor was administered, which indicated that NO may be participated in regulating the homeostasis of Th/Treg cells and subsequent liver inflammation during sepsis. [ABSTRACT FROM AUTHOR]