Background: The poor prognosis of esophageal squamous cell carcinoma (ESCC) highlights the need for novel strategies against this disease. Our previous study suggested the involvement of CCL2 and tumor associated macrophages (TAMs) in esophageal carcinogenesis. Despite the recognition of TAMs as a promising target for cancer treatment, mechanisms underlying its infiltration, activation and tumor-promotive function in ESCC remain unknown. Methods: Human esophageal tissue array and TCGA database were used to evaluate the clinical relevance of CCL2 and TAMs in ESCC. F344 rats and C57BL/6 mice were treated with N-nitrosomethylbenzylamine (NMBA) to establish orthotopic models of esophageal carcinogenesis. CCL2/CCR2 gene knockout mice and macrophage-specific PPARG gene knockout mice were respectively used to investigate the role of infiltration and polarization of TAMs in ESCC. CCL2-mediated monocyte chemotaxis was estimated in malignantly transformed Het-1A cells. THP-1 cells were used to simulate TAMs polarization in vitro. RNA-sequencing was performed to uncover the mechanism. Results: Increasing expression of CCL2 correlated with TAMs accumulation in esophageal carcinogenesis, and they both predicts poor prognosis in ESCC cohort. Animal studies show blockade of CCL2-CCR2 axis strongly reduces tumor incidence by hindering TAMs recruitment and thereby potentiates the antitumor efficacy of CD8 + T cells in the tumor microenvironment. More importantly, M2 polarization increases PD-L2 expression in TAMs, resulting in immune evasion and tumor promotion through PD-1 signaling pathway. Conclusion: This study highlights the role of CCL2-CCR2 axis in esophageal carcinogenesis. Our findings provide new insight into the mechanism of immune evasion mediated by TAMs in ESCC, suggesting the potential of TAMstargeted strategies for ESCC prevention and immunotherapy.
The putative tumor suppressor miR145 is transcriptionally regulated by TP53 and is downregulated in many tumors; however, its role in prostate cancer is unknown. On the other hand, BCL2/adenovirus E1B 19-kDa interacting protein 3 (BNIP3) is overexpressed in various tumors, including prostate cancer, and may transcriptionally repress the apoptosis-inducing factor (AIF) gene. Although BNIP3 transcription is controlled by hypoxia-inducible factor 1α (also elevated in prostate cancer), we postulated the posttranscriptional regulation of BNIP3 by miR145 through bioinformatics analysis, and herein we experimentally showed that miR145 negatively regulated BNIP3 by targeting its 3′-untranslated region. Artificial overexpression of miR145 by using adenoviral vectors in prostate cancer PC-3 and DU145 cells significantly downregulated BNIP3, together with the upregulation of AIF, reduced cell growth, and increased cell death. Artificial overexpression of wild-type TP53 in PC-3 cells (which lack TP53 protein) and DU145 cells (in which mutated nonfunctioning TP53 is expressed) significantly upregulated miR145 expression with consequent effects on BNIP3 and cell behavior as with miR145 overexpression. Analysis of prostate cancer (n = 134) and benign prostate (n = 83) tissue sample showed significantly decreased miR145 and increased BNIP3 expression in prostate cancer (P < 0.001), particularly in those with tumor progression, and both molecular changes were associated with unfavorable outcome. Abnormalities of the miR145-BNIP3 pair as part of TP53-miR145-BNIP3-AIF network may play a major role in prostate cancer pathogenesis and progression. Cancer Res; 70(7); 2728-38. ©2010 AACR.
BackgroundEmerging studies show that long noncoding RNAs (lncRNAs) play important roles in carcinogenesis and cancer progression. The lncRNA ZEB1 antisense 1 (ZEB1-AS1) derives from the promoter region of ZEB1 and we still know little about its expressions, roles and mechanisms.MethodsRACE was used to obtain the sequence of ZEB1-AS1. RNA interference was used to decrease ZEB1-AS1 expression. Adenovirus expression vector was used to increase ZEB1-AS1 expression. CHIP and RIP were used to detect the epigenetic mechanisms by which ZEB1-AS1 regulated ZEB1. CCK8 assay, wound healing assay and transwell assay were used to measure proliferation and migration of prostate cancer cells.ResultsIn this study, in prostate cancer cells, we found that RNAi-mediated downregulation of ZEB1-AS1 induced significant ZEB1 inhibition while artificial overexpression of ZEB1-AS1 rescued ZEB1 expression, which means that ZEB1-AS1 promotes ZEB1 expression. Also, ZEB1-AS1 indirectly inhibited miR200c, the well-known target of ZEB1, and upregulated miR200c’s target BMI1. Mechanistically, ZEB1-AS1 bound and recruited histone methyltransferase MLL1 to the promoter region of ZEB1, induced H3K4me3 modification therein, and activated ZEB1 transcription. Biologically, ZEB1-AS1 promoted proliferation and migration of prostate cancer cells.ConclusionsCollectively, ZEB1-AS1 functions as an oncogene in prostate cancer via epigenetically activating ZEB1 and indirectly regulating downstream molecules of ZEB1.
The presence of IDC-P was significantly associated with rapid progression of CRPC. And its presence could suggest the poor response to initial ADT and sequential docetaxel-based chemotherapy. Detection of IDC-P should be of importance in CRPC, and re-biopsy at the time of CRPC might be one of practical solutions. The mechanism of the ADT and docetaxel resistance to IDC-P needed to be further investigated.
dHOX cluster genes are activated sequentially in their positional order along the chromosome during vertebrate development. This phenomenon, known as temporal colinearity, depends on transcriptional silencing of 5= HOX genes. Chromatin looping was recently identified as a conserved feature of silent HOX clusters, with CCCTC-binding factor (CTCF) binding sites located at the loop bases. However, the potential contribution of CTCF to HOX cluster silencing and the underlying mechanism have not been established. Here, we demonstrate that the HOXA locus is organized by CTCF into chromatin loops and that CTCF depletion causes significantly enhanced activation of HOXA3 to -A7, -A9 to -A11, and -A13 in response to retinoic acid, with the highest effect observed for HOXA9. Our subsequent analyses revealed that CTCF facilitates the stabilization of Polycomb repressive complex 2 (PRC2) and trimethylated lysine 27 of histone H3 (H3K27me3) at the human HOXA locus. Our results reveal that CTCF functions as a controller of HOXA cluster silencing and mediates PRC2-repressive higher-order chromatin structure. HOX genes are organized in clusters in vertebrate genomes and are essential for the patterning of the anterior-posterior body axis. These genes are activated in a temporal-spatial manner according to their position along the chromosome in vertebrates. This phenomenon, temporal-spatial colinearity, is pivotal for the correct patterning of animal bodies and depends on the proper silencing of 5= HOX genes (1). In a cellular model, a progressive transition from a repressed to an active chromatin state along the cluster from 3= to 5= has been proposed to mediate HOX colinearity (2-5), accompanied by nuclear reorganization (6-9) and changes in the higher-order chromatin structure of the clusters (10). A recent study revealed a transition in HOX cluster architecture from an initial single 3-dimensional (3-D) structure to a bimodal state that separates the active and inactive genes during colinear activation of HOX genes in mouse embryos (11). Whether spatial chromatin organization is the cause or a consequence of colinear activation and 5= silencing remains unknown. In addition, the factors responsible for the organization of the higher-order chromatin structure of HOX clusters remain to be identified.Recent findings have indicated that CCCTC-binding factor (CTCF) acts as a "master weaver" of the genome (12). Approximately 20,000 CTCF-binding sites (CBSs) have been identified in the human genome (13-15). These sites are frequently associated with cohesin complexes, which mediate sister chromatid cohesion during mitosis and gene regulation in postmitotic cells (16)(17)(18)(19). Multiple highly conserved CBSs have been identified in the human HOXA cluster. Bioinformatics analyses have suggested that CTCF mediates 3-D structure and thereby regulates gene expression in HOX clusters (10). CTCF-binding site 5 in the HOXA cluster (CBS5) has been reported to function as a developmental stage-specific insulator that regulates the expressio...
The aim of this study was to examine symptoms of posttraumatic stress disorder (PTSD), depression, and anxiety among junior high school students in worst-hit areas 3 years after the Wenchuan earthquake. Analyses were carried out on 373 of the 377 students enrolled. In addition to obtaining demographic characteristics, the Impact of Event Scale-Revised, the Zung Self-rating Depression Scale, the Zung Self-rating Anxiety Scale, and an Earthquake exposure screening scale were administered. It was found that 29.6%, 44.8%, and 37.6% of participants reported clinical symptoms of PTSD, depression, and anxiety, respectively. PTSD, depression, and anxiety were highly comorbid. Having witnessed someone being killed, family members being killed, close friends seriously injured or being killed, and felt scared remained as significant predictors for PTSD. Having witnessed someone seriously injured and felt scared remained as significant predictors for depression. Having witnessed someone seriously injured, witnessed someone being killed, and felt scared remained as significant predictors for anxiety.
Propofol inducescell death in MDA-MB-435 cells via inactivation of miR-24/p27 signal pathway.
Macrophage polarization is mainly steered by metabolic reprogramming in the tissue microenvironment, thus leading to distinct outcomes of various diseases. However, the role of lipid metabolism in the regulation of macrophage alternative activation is incompletely understood. Using human THP-1 and mouse bone marrow derived macrophage polarization models, we revealed a pivotal role for arachidonic acid metabolism in determining the phenotype of M2 macrophages. We demonstrated that macrophage M2 polarization was inhibited by arachidonic acid, but inversely facilitated by its derived metabolite prostaglandin E2 (PGE2). Furthermore, PPARγ bridges these two seemingly unrelated processes via modulating oxidative phosphorylation (OXPHOS). Through inhibiting PPARγ, PGE2 enhanced OXPHOS, resulting in the alternative activation of macrophages, which was counterweighted by the activation of PPARγ. This connection between PGE2 biosynthesis and macrophage M2 polarization also existed in human and mouse esophageal squamous cell carcinoma. Our results highlight the critical role of arachidonic acid and metabolic PGE2 as immune regulators in modulating tissue homeostasis and pathological process.
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