BCL2 G quadruplex-binding small molecules: Current status and prospects for the development of next-generation anticancer therapeutics

B cell lymphoma 2 (BCL2) overexpression in a range of human tumors is often related to chemotherapy resistance and poor prognosis. GC-rich regions upstream of the P1 promoter in human BCL2 can form G-quadruplex (G4) structures through the stacking of four Hoogsteen-paired guanine bases. Stabilizing the G4 fold implies the inhibition of BCL2 expression and, thus, small molecules that selectively bind to the G4 are promising anticancer candidates. In this review, we discuss the structural aspects, binding affinity, selectivity, and biological activity of well-characterized BCL2 G4 binding ligands in vitro and in vivo. We also explore future directions in the research and development of G4-based anticancer therapeutics.     

Cancer Stem Cells and Circulatory Tumor Cells Promote Breast Cancer Metastasis

Breast cancer (BC) is a highly metastatic, pathological cancer that significantly affects women worldwide. The mortality rate of BC is related to its heterogeneity, aggressive phenotype, and metastasis. Recent studies have highlighted that the tumor microenvironment (TME) is critical for the interplay between metastasis mediators in BC. BC stem cells, tumor-derived exosomes, circulatory tumor cells (CTCs), and signaling pathways dynamically remodel the TME and promote metastasis. This review examines the cellular and molecular mechanisms governing the epithelial to mesenchymal transition (EMT) that facilitate metastasis. This review also discusses the role of cancer stem cells (CSCs), tumor-derived exosomes, and CTs in promoting BC metastasis. Furthermore, the review emphasizes major signaling pathways that mediate metastasis in BC. Finally, the interplay among CSCs, exosomes, and CTCs in mediating metastasis have been highlighted. Therefore, understanding the molecular cues that mediate the association of CSCs, exosomes, and CTCs in TME helps to optimize systemic therapy to target metastatic BC.     

Redox active or thiol reactive? Optimization of rapid screens to identify less evident nuisance compounds

Compounds that exhibit assay interference or undesirable mechanisms of bioactivity are routinely encountered in assays at various stages of drug discovery. We observed that assays for the investigation of thiol-reactive and redox-active compounds have not been collected in a comprehensive review. Here, we review these assays and subject them to experimental optimization to improve their reliability. We demonstrate the usefulness of our assay cascade by assaying a library of bioactive compounds, chemical probes, and a set of approved drugs. These high-throughput assays should complement the array of wet-lab and in silico assays during the initial stages of hit discovery campaigns to pursue only hit compounds with tractable mechanisms of action.     

Different inflammatory cytokines release after open and endovascular reconstructions influences wound healing

Prodromal signs of a non‐healing wound after revascularisation, which might be strictly linked with impending failure of vascular reconstructions, are associated with an inflammatory response mediated by several circulating adhesion molecules, extracellular endopeptidases, and cytokines. The aim of our study was to investigate the role of selected plasma biomarkers in the prediction of both wound healing and failure of infrapopliteal vein graft or percutaneous trans‐luminal angioplasty (PTA) with selective stent positioning of the superficial femoral artery (SFA) in a population affected with critical limb ischaemia. A total of 68 patients who underwent either surgical or endovascular revascularisation of the inferior limb with autologous saphenous vein infrapopliteal bypass or PTA and selective stenting of the SFA were enrolled in our study. Patients were divided into two groups according to treatment: 41 patients were included in Group 1 (open surgery) and 27 in Group 2 (endovascular procedure). Plasma and blood samples were collected on the morning of surgery and every 6 months thereafter for up to 2 years of follow‐up or until an occlusion occurred of either the vein bypass graft or the vessel treated endovascularly. Fifteen age‐matched healthy male volunteers were considered a reference for biological parameters. Vascular cell adhesion molecule 1 [VCAM‐1]/CD106, inter‐cellular adhesion molecule‐1 [ICAM‐1]/CD54), interleukin‐1 (IL‐1), interleukin‐6 (IL‐6), tumour necrosis factor alpha (TNF‐α), and metalloproteinases (MMP)‐2 and ‐9 plasma levels were measured with enzyme‐linked immunosorbent assay (ELISA) kits. The mean observed time to heal of 54 wounds was 13 ± 4 months, with no statistically significant differences among the groups . The healing failure of the remaining wounds was strictly related to an unsuccessful open (n = 12) or endovascular (n = 8) treatment. The 2‐year primary patency rate was 65% (SE = .09) in Group 1 and 52% (SE = .1) in Group 2. When compared with mean concentration values of Group 1, VCAM‐1 and ICAM‐1 were always significantly higher during follow‐up in patients of Group 2 (P < .05). Furthermore, in the same group, IL‐6 and tumour necrosis factor alpha (TNF‐α) were found to be significantly higher at 6‐ and 12‐month (P < .05) when compared with surgically treated patients. Cox regression analysis showed that elevated plasma levels of VCAM‐1, ICAM‐1, IL‐6, and TNF‐α during follow up were strongly related to impaired wound healing and/or revascularisation failure (P < .05). Elevated plasma levels of inflammatory markers VCAM‐1, ICAM‐1, IL‐6, and TNF‐α may be related to the failure of wound healing and revascularisation procedures. Interestingly, we have observed that endovascular treatments cause a higher level of these inflammation biomarkers when compared with a vein graft, although wound‐healing and patency and limb salvage rates are not influenced.     

Innate immune recognition and modulation in hepatitis D virus infection

Hepatitis D virus(HDV) is a global health threat with more than 15 million humans affected. Current treatment options are largely unsatisfactory leaving chronically infected humans at high risk to develop liver cirrhosis and hepatocellular carcinoma. HDV is the only human satellite virus known. It encodes only two proteins, and requires Hepatitis B virus(HBV) envelope protein expression for productive virion release and spread of the infection. How HDV could evolve and why HBV was selected as a helper virus remains unknown. Since the discovery of Na+-taurocholate co-transporting polypeptide as the essential uptake receptor for HBV and HDV, we are beginning to understand the interactions of HDV and the immune system. While HBV is mostly regarded a stealth virus, that escapes innate immune recognition, HBV-HDV coinfection is characterized by a strong innate immune response. Cytoplasmic RNA sensor melanoma differentiation antigen 5 has been reported to recognize HDV RNA replication and activate innate immunity. Innate immunity, however, seems not to impair HDV replication while it inhibits HBV. In this review, we describe what is known up-to-date about the interplay between HBV as a helper and HDV's immune evasion strategy and identify where additional research is required.     

HMGB‐1, TLR4, IL‐1R1, TNF‐α, and IL‐1β: novel epilepsy markers?

Aim: The purpose of this study was to compare HMGB‐1, TLR4, IL‐1β, IL‐1R1, and TNF‐α levels in patients with mild and severe epilepsy with those in a healthy control group. Methods: Children aged 4–17 years, diagnosed with epilepsy for at least three years and with no progressive neurological disease, metabolic disease or infection, were selected for the study. The severe epilepsy group consisted of 28 children with at least one episode a week despite receiving three or more antiepileptic drugs. The mild epilepsy group consisted of 29 children with no seizures in the previous year, receiving only one antiepileptic drug, while 27 healthy children were selected as the control group. HMGB‐1, TLR4, IL‐1R1, TNF‐α and IL‐1β levels were investigated in these three groups. The MRI findings and clinical characteristics of the patients in the epilepsy group were also compared with these markers. Results: HMGB‐1, TLR4, TNF‐α, and IL‐1β levels in the severe epilepsy group were higher than in the control group and the mild epilepsy group (p<0.05), and were higher in the mild epilepsy group than in the control group (p<0.05). IL‐1R1 was also higher in the severe epilepsy group than in the control group (p<0.05). Conclusion: In this first report to identity a possible correlation between HMGB‐1, TLR4, IL‐1β, IL‐1R1, and TNF‐α levels and severity of epilepsy, our data demonstrates that the serum level of these cytokines is higher in cases of drug‐refractory epilepsy.     

免疫共刺激分子与自身免疫性疾病的研究进展

正常机体的免疫系统具有区别"自己"和"非己"的能力,对非己抗原能够发生免疫应答,对自身抗原则是处于无应答或微弱应答状态,时刻处于"免疫激活-免疫耐受"的动态平衡状态。然而,如果正常的免疫耐受被打破,将"自己"识别成"非己",处于非正常免疫激活状态的T细胞就会持续迁延的对自身抗原产生异常的免疫应答,结果会导致自身免疫性疾病(ADS)的发生。因此,"无效"的免疫识别和免疫应答成为自身免疫性疾病的发病的主要致病机制。免疫共刺激分子(co-stimulatory molecule)作为连接抗原递呈细胞(APC)和免疫细胞(T细胞,B细胞)的重要纽带,有研究已经证实,正性免疫共刺激分子的高表达和负性免疫共刺激分子的低表达都会导致自身免疫耐受的缺陷,进而引发自身免疫性疾病。依据中医药"纠偏","扶正"的治疗特色。本文通过对4种典型性的自身免疫性疾病:系统性则是以红斑狼疮(SLE)和类风湿性关节炎(RA)为代表;器官特异性则是以多发性硬化症(MS)和Ⅰ型糖尿病(T1DM)发病机制进行探讨,依赖于这4种疾病发病过程中免疫共刺激分子对免疫识别与免疫应答的重要影响,并且依托于中医药对自身免疫平衡调节的作用,结合近十年来的相关文献,对免疫共刺激分子与自身免疫性疾病之间的关系进行论述,探寻不同的免疫共刺激分子在不同的自身免疫病中的共性,并初探中药以PD1-PDL1为药物靶点治疗自身免疫病的可行性。     

PPARγ: the dominant regulator among PPARs in dry eye lacrimal gland and diabetic lacrimal gland

AIM: To determine whether lectin-like ox-LDL receptor (LOX-1) regulates adhesion molecules expression and neutrophil infiltration in A. fumigatus keratitis of C57BL/6 mice.METHODS: C57BL/6 mice were pretreated with a neutralizing antibody to LOX-1 (5 μg/5 μL) or control nonspecific IgG (5 μg/5 μL), LOX-1 inhibitor Poly-I (2 μg/5 μL) or PBS by subconjunctival injection. Fungal keratitis mouse models of C57BL/6 mice were established by scraping corneal central epithelium, smearing A. fumigatus on the corneal surface and covering the eye with contact lenses. The corneal response to infection was assessed via clinical score. The mRNA levels of the adhesion molecules ICAM-1, VCAM-1, P-selectin and E-selectin were tested in control and infected corneas by RT-PCR. The protein levels of ICAM-1 were evaluated by immunofluorescence (IF) and Western blot. Neutrophils were extracted from the abdominal cavity of C57BL/6 mice followed by pretreatment using antibody to LOX-1 (10 μg/mL) or control nonspecific IgG (10 μg/mL), the Poly-I (4 μg/mL) or PBS. The cells were then stimulated with A. fumigatus and tested mRNA and protein levels of LFA-1 using RT-PCR and Western blot. IF and myeloperoxidase (MPO) assays were used to assess neutrophil infiltration in mice corneas.RESULTS: Pretreatment of LOX-1 antibody or the Poly-I reduced the degree of inflammation of cornea and decreased the clinical fungal keratitis score compared with pretreatment of IgG or PBS. And these pretreatment also displayed an obvious decline in the mRNA levels of ICAM-1, VCAM-1, P-selectin, E-selectin and LFA-1 expression compared with control groups . Furthermore, pretreated with LOX-1 antibody or Poly-I, the protein levels of ICAM-1 and LFA-1 also decreased compared with control groups. Neutrophil infiltration in the cornea was significantly reduced after pretreatment of LOX-1 antibody or Poly-I compared with control groups by IF and MPO assays. CONCLUSION: These data provide evidence that inhibition of LOX-1 can decrease the expression of adhesion molecules and thus reduce neutrophil infiltration in A. fumigatus infected corneas of C57BL/6 mice.