Summary In colorectal cancer, tumor budding at the invasive front (peritumoral budding) is an established prognostic parameter and decreased in mismatch repair–deficient tumors. In contrast, the ...clinical relevance of tumor budding within the tumor center (intratumoral budding) is not yet known. The aim of the study was to determine the correlation of intratumoral budding with peritumoral budding and mismatch repair status and the prognostic impact of intratumoral budding using 2 independent patient cohorts. Following pancytokeratin staining of whole-tissue sections and multiple-punch tissue microarrays, 2 independent cohorts (group 1: n = 289; group 2: n = 222) with known mismatch repair status were investigated for intratumoral budding and peritumoral budding. In group 1, intratumoral budding was strongly correlated to peritumoral budding ( r = 0.64; P < .001) and less frequent in mismatch repair–deficient versus mismatch repair–proficient cases ( P = .177). Sensitivity and specificity for lymph node positivity were 72.7% and 72.1%. In mismatch repair–proficient cancers, high-grade intratumoral budding was associated with right-sided location ( P = .024), advanced T stage ( P = .001) and N stage pN ( P < .001), vascular invasion ( P = .041), infiltrating tumor margin ( P = .003), and shorter survival time ( P = .014). In mismatch repair–deficient cancers, high intratumoral budding was linked to higher tumor grade ( P = .004), vascular invasion ( P = .009), infiltrating tumor margin ( P = .005), and more unfavorable survival time ( P = .09). These associations were confirmed in group 2. High-grade intratumoral budding was a poor prognostic factor in univariate ( P < .001) and multivariable analyses ( P = .019) adjusting for T stage, N stage distant metastasis, and adjuvant therapy. These preliminary results on 511 patients show that intratumoral budding is an independent prognostic factor, supporting the future investigation of intratumoral budding in larger series of both preoperative and postoperative rectal and colon cancer specimens.
Estrogens are known modulators of monocyte/macrophage functions; however, the underlying mechanism has not been clearly defined. Recently, a number of estrogen receptor molecules and splice variants ...were identified that exert different and sometimes opposing actions. We assessed the expression of estrogen receptors and explored their role in mediating estrogenic anti-inflammatory effects on human primary monocytes. We report that the only estrogen receptors expressed are estrogen receptor-α 36-kDa splice variant and G-protein coupled receptor 30/G-protein estrogen receptor 1, in a sex-independent manner. 17-β-Estradiol inhibits the LPS-induced IL-6 inflammatory response, resulting in inhibition of NF-κB transcriptional activity. This is achieved via a direct physical interaction of ligand-activated estrogen receptor-α 36-kDa splice variant with the p65 component of NF-κB in the nucleus. G-protein coupled receptor 30/G-protein estrogen receptor 1, which also physically interacts with estrogen receptor-α 36-kDa splice variant, acts a coregulator in this process, because its inhibition blocks the effect of estrogens on IL-6 expression. However, its activation does not mimic the effect of estrogens, on neither IL-6 nor NF-κB activity. Finally, we show that the estrogen receptor profile observed in monocytes is not modified during their differentiation to macrophages or dendritic cells in vitro and is shared in vivo by macrophages present in atherosclerotic plaques. These results position estrogen receptor-α 36-kDa splice variant and G-protein coupled receptor 30 as important players and potential therapeutic targets in monocyte/macrophage-dependent inflammatory processes.
Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors that play pivotal roles in the regulation of a very large number of biological processes including ...inflammation. Using specific examples, this paper focuses on the interplay between PPARs and innate immunity/inflammation and, when possible, compares it among species. We focus on recent discoveries establishing how inflammation and PPARs interact in the context of obesity-induced inflammation and type 2 diabetes, mostly in mouse and humans. We illustrate that PPARγ ability to alleviate obesity-associated inflammation raises an interesting pharmacologic potential. In the light of recent findings, the protective role of PPARα and PPARβ/δ against the hepatic inflammatory response is also addressed. While PPARs agonists are well-established agents that can treat numerous inflammatory issues in rodents and humans, surprisingly very little has been described in other species. We therefore also review the implication of PPARs in inflammatory bowel disease; acute-phase response; and central, cardiac, and endothelial inflammation and compare it along different species (mainly mouse, rat, human, and pig). In the light of the data available in the literature, there is no doubt that more studies concerning the impact of PPAR ligands in livestock should be undertaken because it may finally raise unconsidered health and sanitary benefits.
Obese adipose tissue is characterized by infiltration of macrophages. We and others recently showed that a specific subset of macrophages is recruited to obese adipose and muscle tissue. This subset ...expresses CD11c and produces high levels of proinflammatory cytokines that are linked to the development of obesity-associated insulin resistance. Here, we used a conditional cell ablation system, based on transgenic expression of the diphtheria toxin receptor under the control of the CD11c promoter, to study the effects of depletion of CD11c
+ cells in obese mouse models. Our results show that CD11c
+ cell depletion results in rapid normalization of insulin sensitivity. Furthermore, CD11c
+ cell ablation leads to a marked decrease in inflammatory markers, both locally and systemically, as reflected by gene expression and protein levels. Together, these results indicate that these CD11c
+ cells are a potential therapeutic target for treatment of obesity-related insulin resistance and type II diabetes.
The insulin-like growth factors (IGF)-I and -II have a predominant role in fetal growth and development. IGFs are involved in the proliferation, differentiation and apoptosis of fetal cells in vitro ...and the IGF serum concentration has been shown to be closely correlated with fetal growth and length. IGF transcripts and peptides have been detected in almost every fetal tissue from as early in development as pre‑implantation to the final maturation stage. Furthermore, IGFs have been demonstrated to be involved in limb morphogenesis. However, although ablation of Igf genes in mice resulted in growth retardation and delay in skeletal maturation, no impact on outgrowth and patterning of embryonic limbs was observed. Additionally, various molecular defects in the Igf1 and Igf1r genes in humans have been associated with severe intrauterine growth retardation and impaired skeletal maturation, but not with truncated limbs or severe skeletal dysplasia. The conflicting data between in vitro and in vivo observations with regard to bone morphogenesis suggests that IGFs may not be the sole trophic factors involved in fetal skeletal growth and that redundant mechanisms may exist in chondro- and osteogenesis. Further investigation is required in order to elucidate the functions of IGFs in skeletal development.
Burn is accompanied by long-lasting immuno-metabolic alterations referred to as hypermetabolism that are characterized by a considerable increase in resting energy expenditure and substantial ...whole-body catabolism. In burned patients, the length and magnitude of the hypermetabolic state is the highest of all patients and associated with profoundly increased morbidity and mortality. Unfortunately, the mechanisms involved in hypermetabolism are essentially unknown. We hypothesized that the adipose tissue plays a central role for the induction and persistence of hypermetabolism post-burn injury. Here, we show that burn induces a switch in the phenotype of the subcutaneous fat from white to beige, with associated characteristics such as increased mitochondrial mass and UCP1 expression. Our results further demonstrate the significant role of catecholamines and interleukin-6 in this process. We conclude that subcutaneous fat remodeling and browning represent an underlying mechanism that explains the elevated energy expenditure in burn-induced hypermetabolism.
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•Burn injury results in browning of the subcutaneous fat in rodents and humans•Browning occurs beyond or after 10 days post-burn injury in humans•Markers of browning are reduced by the beta-blocker propranolol•IL-6 is required for browning in mice post-burn injury
Severe trauma such as burn injury is followed by a hypermetabolic state that is characterized by an elevation in energy expenditure and insulin resistance. Patsouris et al. show that severe burn injury results in browning of the subcutaneous fat; this may explain why these patients develop hypermetabolism.
The fasting-induced adipose factor (FIAF, ANGPTL4, PGAR, HFARP) was previously identified as a novel adipocytokine that was
up-regulated by fasting, by peroxisome proliferator-activated receptor ...agonists, and by hypoxia. To further characterize FIAF,
we studied regulation of FIAF mRNA and protein in liver and adipose cell lines as well as in human and mouse plasma. Expression
of FIAF mRNA was up-regulated by peroxisome proliferator-activated receptor α (PPARα) and PPARβ/δ agonists in rat and human
hepatoma cell lines and by PPARγ and PPARβ/δ agonists in mouse and human adipocytes. Transactivation, chromatin immunoprecipitation,
and gel shift experiments identified a functional PPAR response element within intron 3 of the FIAF gene. At the protein level,
in human and mouse blood plasma, FIAF was found to be present both as the native protein and in a truncated form. Differentiation
of mouse 3T3-L1 adipocytes was associated with the production of truncated FIAF, whereas in human white adipose tissue and
SGBS adipocytes, only native FIAF could be detected. Interestingly, truncated FIAF was produced by human liver. Treatment
with fenofibrate, a potent PPARα agonist, markedly increased plasma levels of truncated FIAF, but not native FIAF, in humans.
Levels of both truncated and native FIAF showed marked interindividual variation but were not associated with body mass index
and were not influenced by prolonged semistarvation. Together, these data suggest that FIAF, similar to other adipocytokines
such as adiponectin, may partially exert its function via a truncated form.
Human zona pellucida (ZP) is composed of four glycoproteins, namely ZP1, ZP2, ZP3 and ZP4. ZP proteins form heterodimers, which are incorporated into filaments through a common bipartite polymerizing ...component, designated as the ZP domain. The latter is composed of two individually folded subdomains, named ZP‐N and ZP‐C. Here, we have synthesized six ‘aggregation‐prone’ peptides, corresponding to a common interface of human ZP2, ZP3 and ZP4. Experimental results utilizing electron microscopy, X‐ray diffraction, ATR FT‐IR spectroscopy and polarizing microscopy indicate that these peptides self‐assemble forming fibrils with distinct amyloid‐like features. Finally, by performing detailed modeling and docking, we attempt to shed some light in the self‐assembly mechanism of human ZP proteins.
In most lymphomas, p53 signaling pathway is inactivated by various mechanisms independent to p53 gene mutations or deletions. In many cases, p53 function is largely regulated by alterations in the ...protein abundance levels by the action of E3 ubiquitin-protein ligase MDM2, targeting p53 to proteasome-mediated degradation. In the present study, an integrating transcriptomics and proteomics analysis was employed to investigate the effect of p53 activation by a small-molecule MDM2-antagonist, nutlin-3a, on three lymphoma cell models following p53 activation. Our analysis revealed a system-wide nutlin-3a-associated effect in all examined lymphoma types, identifying in total of 4037 differentially affected proteins involved in a plethora of pathways, with significant heterogeneity among lymphomas. Our findings include known p53-targets and novel p53 activation effects, involving transcription, translation, or degradation of protein components of pathways, such as a decrease in key members of PI3K/mTOR pathway, heat-shock response, and glycolysis, and an increase in key members of oxidative phoshosphorylation, autophagy and mitochondrial translation. Combined inhibition of HSP90 or PI3K/mTOR pathway with nutlin-3a-mediated p53-activation enhanced the apoptotic effects suggesting a promising strategy against human lymphomas. Integrated omic profiling after p53 activation offered novel insights on the regulatory role specific proteins and pathways may have in lymphomagenesis.
The endoplasmic reticulum (ER) is a critical organelle that synthesizes secretory proteins and serves as the main calcium storage site of the cell. The accumulation of unfolded proteins at the ER ...results in ER stress. Although the association between ER stress and the pathogenesis of many metabolic conditions have been well characterized using both in vivo and in vitro models, no standardized model concerning ER stress exists. Here, we report a standardized model of ER stress using two well-characterized ER stress-inducing agents, thapsigargin and tunicamycin. Our aim in this current study was 2-fold: to characterize and establish which agent is optimal for in vitro use to model acute ER stress and to evaluate which agent is optimal for in vivo use. To study the first aim we used two well-established metabolic cell lines; human hepatocellular carcinoma (HepG2s) and differentiated mouse adipocytes (3T3-L1). In the second aim we utilized C57BL/6J mice that were randomized into three treatment groups of sham, thapsigargin, and tunicamycin. Our in vitro results showed that tunicamycin worked as a rapid and efficacious inducer of ER stress in adipocytes consistently, whereas thapsigargin and tunicamycin were equally effective in inducing ER stress in hepatocytes. In regards to our in vivo results, we saw that tunicamycin was superior in not only inducing ER stress but also recapturing the metabolic alterations associated with ER stress. Thus, our findings will help guide and inform researchers as to which ER stress agent is appropriate with regards to their model.
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