Colitis and colitis-associated cancer are exacerbated in mice deficient for tumor protein 53-induced nuclear protein 1

Broccoli Cultivated with Deep Sea Water Mineral Fertilizer Enhances Anti-Cancer and Anti-Inflammatory Effects of AOM/DSS-Induced Colorectal Cancer in C57BL/6N Mice

This study aimed to determine the alleviating effect of broccoli grown with deep sea water mineral (DSWM) fertilizer extracted from deep sea water on the development of colorectal cancer in C57BL/6N mice treated with AOM/DSS. Naturaldream Fertilizer Broccoli (NFB) cultured with deep sea water minerals (DSWM) showed a higher antioxidant effect and mineral content. In addition, orally administered NFB, showed a level of recovery in the colon and spleen tissues of mice compared with those in normal mice through hematoxylin and eosin (H&E) staining. Orally administered NFB showed the inhibition of the expression of inflammatory cytokine factors IL-1β, IL-6, TNF, IFN-γ, and IL-12 while increasing the expression of IL-10. Furthermore, the expression of inflammatory cytokines and NF-κB in the liver tissue was inhibited, and that of inflammatory enzymes, such as COX-2 and iNOS, was reduced. In the colon tissue, the expression of p53 and p21 associated with cell cycle arrest increased, and that of Bcl-2 associated with apoptosis decreased. Additionally, the expression of Bax, Bad, Bim, Bak, caspase 9, and caspase 3 increased, indicating enhanced activation of apoptosis-related factors. These results demonstrate that oral administration of broccoli cultivated using DSWM significantly restores spleen and colon tissues and simultaneously inhibits the NF-κB pathway while significantly decreasing cytokine expression. Moreover, by inducing cell cycle arrest and activating cell apoptosis, they also suggest alleviating AOM/DSS-induced colon cancer symptoms in C57BL/6N mice.

Effects of polyphenolic maqui (Aristotelia chilensis) extract on the inhibition of NLRP3 inflammasome and activation of mast cells in a mouse model of Crohn's disease-like colitis

Introduction

Crohn's disease (CD) involves activation of mast cells (MC) and NF-кB in parallel with the PPAR-α/NLRP3 inflammasome/IL-1β pathway in the inflamed colon. Whether polyphenols from maqui (Aristotelia chilensis) represent a natural alternative treatment for CD is unclear. Therefore, we used an animal model of 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced CD-like colitis to investigate protective effects of maqui extract through monitoring NLRP3 inflammasome and MC activation in colon tissue.

Methods

Maqui extract was administered via orogastric route to mice after (post-Treatment group) or prior (pre-Treatment group) to TNBS-induction. Colon pathology was characterized by histoarchitectural imaging, disease activity index (DAI), and assessing NF-кB, p-NF-кB, PPAR-α/NLRP3 expression and IL-1β levels.

Results

Compared to mice treated with TNBS alone administration of anthocyanin-rich maqui extract improved the DAI, colon histoarchitecture and reduced both colon wet-weight and transmural inflammation. Induction with TNBS significantly increased colonic NLPR3 inflammasome activation, while co-treatment with maqui extract (either post- or pre-Treatment) significantly downregulated NLRP3, ASC and caspase-1 levels, which manifested as reduced colonic IL-1β levels. Supplemented maqui extract marginally diminished NF-кB activity in epithelial cells but reached statistical significance in immune cells (as judged by decreased NF-кB phosphorylation). PPAR-α signaling was largely unaffected by Maqui whereas MC infiltration into the colon mucosa and submucosa decreased and their level of degranulation was suppressed.

Conclusion

These outcomes show the post- and pre- Treatment effect of a polyphenolic extract rich in anthocyanins from maqui the acute phase of TNBS- induced CD-like colitis is linked to suppression of the NLRP3 inflammasome and reduced MC responses. These data indicate that maqui extract represents a potential nutraceutical for the treatment of inflammatory bowel disease (IBD).

Extraintestinal Manifestations in Induced Colitis: Controversial Effects of N-Acetylcysteine on Colon, Liver, and Kidney

Ulcerative colitis (UC) is a chronic and recurrent inflammatory bowel disease (IBD) characterized by continuous inflammation in the colonic mucosa. Extraintestinal manifestations (EIM) occur due to the disruption of the intestinal barrier and increased permeability caused by redox imbalance, dysbiosis, and inflammation originating from the intestine and contribute to morbidity and mortality. The aim of this study is to investigate the effects of oral N-acetylcysteine (NAC) on colonic, hepatic, and renal tissues in mice with colitis induced by dextran sulfate sodium (DSS). Male Swiss mice received NAC (150 mg/kg/day) in the drinking water for 30 days before and during (DSS 5% v/v; for 7 days) colitis induction. On the 38th day, colon, liver, and kidney were collected and adequately prepared for the analysis of oxidative stress (superoxide dismutase (SOD), catalase (CAT), glutathione reduced (GSH), glutathione oxidized (GSSG), malondialdehyde (MDA), and hydrogen peroxide (H2O2)) and inflammatory biomarkers (myeloperoxidase (MPO) -, tumor necrosis factor alpha - (TNF-α, and interleukin-10 (IL-10)). In colon, NAC protected the histological architecture. However, NAC did not level up SOD, in contrast, it increased MDA and pro-inflammatory effect (increased of TNF-α and decreased of IL-10). In liver, colitis caused both oxidative (MDA, SOD, and GSH) and inflammatory damage (IL-10). NAC was able only to increase GSH and GSH/GSSG ratio. Kidney was not affected by colitis; however, NAC despite increasing CAT, GSH, and GSH/GSSG ratio promoted lipid peroxidation (increased MDA) and pro-inflammatory action (decreased IL-10). Despite some beneficial antioxidant effects of NAC, the negative outcomes concerning irreversible oxidative and inflammatory damage in the colon, liver, and kidney confirm the nonsafety of the prophylactic use of this antioxidant in models of induced colitis, suggesting that additional studies are needed, and its use in humans not yet recommended for the therapeutic routine of this disease.

Inflammatory Bowel Disease-Associated Gut Commensals Degrade Components of the Extracellular Matrix

Extracellular matrix (ECM) remodeling has emerged as a key feature of inflammatory bowel disease (IBD), and ECM fragments have been proposed as markers of clinical disease severity. Recent studies report increased protease activity in the gut microbiota of IBD patients. Nonetheless, the relationship between gut microbiota and ECM remodeling has remained unexplored. We hypothesized that members of the human gut microbiome could degrade the host ECM and that bacteria-driven remodeling, in turn, could enhance colonic inflammation. Through a variety of in vitro assays, we first confirmed that multiple bacterial species found in the human gut are capable of degrading specific ECM components. Clinical stool samples obtained from ulcerative colitis patients also exhibited higher levels of proteolytic activity in vitro, compared to those of their healthy counterparts. Furthermore, culture supernatants from bacteria species that are capable of degrading human ECM accelerated inflammation in dextran sodium sulfate (DSS)-induced colitis. Finally, we identified several of the bacterial proteases and carbohydrate degrading enzymes (CAZymes) that are potentially responsible for ECM degradation in vitro. Some of these protease families and CAZymes were also found in increased abundance in a metagenomic cohort of IBD. These results demonstrate that some commensal bacteria in the gut are indeed capable of degrading components of human ECM in vitro and suggest that this proteolytic activity may be involved in the progression of IBD. A better understanding of the relationship between nonpathogenic gut microbes, host ECM, and inflammation could be crucial to elucidating some of the mechanisms underlying host-bacteria interactions in IBD and beyond. IMPORTANCE Healthy gut epithelial cells form a barrier that keeps bacteria and other substances from entering the blood or tissues of the body. Those cells sit on scaffolding that maintains the structure of the gut and informs our immune system about the integrity of this barrier. In patients with inflammatory bowel disease (IBD), breaks are formed in this cellular barrier, and bacteria gain access to the underlying tissue and scaffolding. In our study, we discovered that bacteria that normally reside in the gut can modify and disassemble the underlying scaffolding. Additionally, we discovered that changes to this scaffolding affect the onset of IBD in mouse models of colitis as well as the abilities of these mice to recover. We propose that this new information will reveal how breaks in the gut wall lead to IBD and will open up new avenues by which to treat patients with IBD.

The Probiotic Effects of the Saccharomyces cerevisiae 28-7 Strain Isolated from Nuruk in a DSS-Induced Colitis Mouse Model

Probiotics are microorganisms that can benefit host health when ingested in a live state, and lactic acid bacteria are the most common type. Among fungi, Saccharomyces boulardii (SB) is the only strain known to have a probiotic function with beneficial effects on colitis; however, information on other probiotic yeast strains is limited. Therefore, this study aimed to discover yeast strains expressing intestinal anti-inflammatory activities by exhibiting probiotic properties in dextran sodium sulfate (DSS)-induced colitis mice model. Nuruk (Korean traditional fermentation starter) containing various microbial strains was used as a source for yeast strains, and S. cerevisiae 28-7 (SC28-7) strain was selected with in vitro and in vivo characteristics to enable survival in the intestines. After 14 days of pretreatment with the yeast strains, DSS was co-administered for six days to induce colitis in mice. The results revealed that the disease activity index score was lowered by SC28-7 treatment compared to the DSS group, and the colon length and weight/length ratio were recovered in a pattern similar to that of the normal group. SC28-7 administration significantly reduced the secretion of pro-inflammatory cytokines in the serum and modified the mRNA expression of inflammatory cytokines (interleukin-1β, transforming growth factor-β, and interferon-γ) and proteins involved in gut barrier functions (mucin 2, mucin 3, zonula occludens-1, and occludin) in colon tissues. These results indicate that SC28-7 attenuates DSS-induced colon damage and inflammation, supporting its future use as a probiotic yeast for treating and preventing intestinal inflammatory diseases such as inflammatory bowel disease.

Chemoprevention with a tea from hawthorn (Crataegus oxyacantha) leaves and flowers attenuates colitis in rats by reducing inflammation and oxidative stress

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A tea from the leaves and flowers of hawthorn is rich in flavonoids, especially vitexin-2-O-rhamnoside.

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Mesalamine and hawthorn tea have positive healing effects in rats with colitis.

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Hawthorn tea reduces the length and area of the brownish necrotic lesions.

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Hawthorn tea diminishes the levels of the inflammatory markers MPO and IL-1β.

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Hawthorn tea regulates the activity of the oxidative stress enzymes CAT and GR.

The purpose of the study was to determine the effects of a tea from the leaves and flowers of Crataegus oxyacantha in rats with colitis. Colitis was induced by administration of 2,4,6-trinitrobenzene sulfonic acid. Hawthorn tea (HT) (100 mg/kg) was given via gavage for 21 days and the mesalamine drug (100 mg/kg) was administrated during the period of disease onset. HT was rich in total phenolic compounds (16.5%), flavonoids (1.8%), and proanthocyanidins (1.5%); vitexin-2-O-rhamnoside was the main compound detected. Mesalamine and the HT diminished the length of the lesions formed in the colon, in addition to reducing the levels of myeloperoxidase and interleukin-1β. Mesalamine was able to significantly reverse the body weight loss, while HT improved the activity of glutathione reductase and catalase. Histological scoring was not changed by the interventions, but it was highly correlated with the necrotic area. HT given at 100 mg/kg can be effective against colitis.

Resolvin D1 suppresses inflammation-associated tumorigenesis in the colon by inhibiting IL-6-induced mitotic spindle abnormality

While failure in resolution of inflammation is considered to increase the risk of tumorigenesis, there is paucity of experimental as well as clinical evidence supporting this association. Resolvin D1 (RvD1) is a representative pro-resolving lipid mediator that is endogenously generated from docosahexaenoic acid for the resolution of inflammation. Here, we report a decreased level of RvD1 in the blood from colorectal cancer patients and mice having inflammation-induced colon cancer, suggesting plasma RvD1 as a potential biomarker for monitoring colorectal cancer. Administration of RvD1 attenuated dextran sodium sulfate (DSS)-induced colitis and azoxymethane (AOM) plus DSS-induced colorectal carcinogenesis by suppressing the production of interleukin-6 (IL-6) and IL-6-mediated chromosomal instability. The protective effect of RvD1 against chromosomal instability is associated with downregulation of IL-6-induced Cyclin D1 expression, which appears to be mediated by blocking the Janus kinase 2 (JAK2)-signal transducer and activator of transcription 3 (STAT3) axis. RvD1 inhibited the STAT3 signaling pathway by interfering with the binding of IL-6 to its receptor (IL-6R), suggesting the novel function of RvD1 as a putative IL-6R antagonist. Together, our findings suggest that RvD1-mediated blockade of IL-6 signal transmission may contribute to inhibition of chromosomal instability and tumorigenesis.

Effects of olives and their constituents on the expression of ulcerative colitis: a systematic review of randomised controlled trials

Extra virgin olive oil is often associated with anti-inflammatory and antioxidant properties. Its effects on inflammatory conditions such as ulcerative colitis (UC), however, have yet to be defined. As such, we aimed to conduct a systematic review and meta-analysis of studies investigating olive-based interventions in UC. A comprehensive database search for randomised controlled trials was performed between 9 July 2018 and 16 August 2018. Studies identified from search alerts were included up to 22 June 2020. Both individuals living with UC at any disease stage and murine models of UC were included in this review. No human trials meeting the eligibility criteria were identified, while nineteen animal studies comprised 849 murine models of UC were included in this review. Pooling of the data could not be performed due to heterogeneous outcomes; however, general trends favouring olive-based interventions were identified. Milder disease expression including weight maintenance, reduced rectal bleeding and well-formed stools favouring olive-based interventions was statistically significant in 16/19 studies, with moderate-to-large effect sizes (-0·66 (95 % CI -1·56, 0·24) to -12·70 (95 % CI -16·8, -8·7)). Olive-based interventions did not prevent the development of colitis-like pathologies in any study. In conclusion, effects of olive-based interventions on murine models of UC appear promising, with milder disease outcomes favouring the intervention in most trials and effect sizes suggesting potential clinical relevance. However, the lack of published randomised controlled human trials warrants further investigation to determine if these effects would translate to individuals living with UC.

Transcriptional Profiling of Porcine Blastocysts Produced In Vitro in a Chemically Defined Culture Medium

The development of chemically defined media is a growing trend in in vitro embryo production (IVP). Recently, traditional undefined culture medium with bovine serum albumin (BSA) has been successfully replaced by a chemically defined medium using substances with embryotrophic properties such as platelet factor 4 (PF4). Although the use of this medium sustains IVP, the impact of defined media on the embryonic transcriptome has not been fully elucidated. This study analyzed the transcriptome of porcine IVP blastocysts, cultured in defined (PF4 group) and undefined media (BSA group) by microarrays. In vivo-derived blastocysts (IVV group) were used as a standard of maximum embryo quality. The results showed no differentially expressed genes (DEG) between the PF4 and BSA groups. However, a total of 2780 and 2577 DEGs were detected when comparing the PF4 or the BSA group with the IVV group, respectively. Most of these genes were common in both in vitro groups (2132) and present in some enriched pathways, such as cell cycle, lysosome and/or metabolic pathways. These results show that IVP conditions strongly affect embryo transcriptome and that the defined culture medium with PF4 is a guaranteed replacement for traditional culture with BSA.

TP53INP1 exerts neuroprotection under ageing and Parkinson's disease-related stress condition

TP53INP1 is a stress-induced protein, which acts as a dual positive regulator of transcription and of autophagy and whose deficiency has been linked with cancer and metabolic syndrome. Here, we addressed the unexplored role of TP53INP1 and of its Drosophila homolog dDOR in the maintenance of neuronal homeostasis under chronic stress, focusing on dopamine (DA) neurons under normal ageing- and Parkinson’s disease (PD)-related context. Trp53inp1^−/− mice displayed additional loss of DA neurons in the substantia nigra compared to wild-type (WT) mice, both with ageing and in a PD model based on targeted overexpression of α-synuclein. Nigral Trp53inp1 expression of WT mice was not significantly modified with ageing but was markedly increased in the PD model. Trp53inp2 expression showed similar evolution and did not differ between WT and Trp53inp1^−/− mice. In Drosophila, pan-neuronal dDOR overexpression improved survival under paraquat exposure and mitigated the progressive locomotor decline and the loss of DA neurons caused by the human α-synuclein A30P variant. dDOR overexpression in DA neurons also rescued the locomotor deficit in flies with RNAi-induced downregulation of dPINK1 or dParkin. Live imaging, confocal and electron microscopy in fat bodies, neurons, and indirect flight muscles showed that dDOR acts as a positive regulator of basal autophagy and mitophagy independently of the PINK1-mediated pathway. Analyses in a mammalian cell model confirmed that modulating TP53INP1 levels does not impact mitochondrial stress-induced PINK1/Parkin-dependent mitophagy. These data provide the first evidence for a neuroprotective role of TP53INP1/dDOR and highlight its involvement in the regulation of autophagy and mitophagy in neurons.

Persimmon-derived tannin ameliorates the pathogenesis of ulcerative colitis in a murine model through inhibition of the inflammatory response and alteration of microbiota

Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) induced by dysregulation of the immune response in the intestinal mucosa. Although the underlying mechanisms of UC development are not fully understood, disruption of gut microbiota, “dysbiosis”, is thought to lead to the development of IBD. Persimmon (Ebenaceae Diospyros kaki Thunb.)-derived tannin, which is a condensed polymeric tannin consisting of catechin groups, has antioxidant, anti-inflammatory, and antimicrobial activities. In this study, we assessed the effect of persimmon-derived tannin on a murine model of UC established by dextran sulfate sodium-induced colitis in female mice. Dietary supplementation of tannin significantly decreased disease activity and colon inflammation. A hydrolysate of tannin directly suppressed expression of inflammatory genes in macrophages in vitro. In faecal microbiota, the relative abundance of Bacteroides was increased significantly by tannin supplementation. Alpha-diversity indices in colitis-induced mice were significantly higher in the tannin diet group compared with the control diet group. Additionally, expansion of Enterobacteriaceae and Enterococcus, which is associated with disease progression of IBD, was remarkably suppressed in the tannin diet group. These results suggest that persimmon-derived tannin ameliorates colon inflammation in UC through alteration of the microbiota composition and immune response, which may be a promising candidate for IBD therapy.

Inhibition of NUPR1-Karyopherin β1 Binding Increases Anticancer Drug Sensitivity

Background: Nuclear protein-1 (NUPR1, also known as p8/Com-1) is a transcription factor involved in the regulation of cellular stress responses, including serum starvation and drug stimulation. Methods: We investigated the mechanism of NUPR1 nuclear translocation involving karyopherin β1 (KPNB1), using a single-molecule binding assay and confocal microscopy. The cellular effects associated with NUPR1–KPNB1 inhibition were investigated by gene expression profiling and cell cycle analysis. Results: The single-molecule binding assay revealed that KPNB1 bound to NUPR1 with a binding affinity of 0.75 nM and that this binding was blocked by the aminothiazole ATZ-502. Following doxorubicin-only treatment, NUPR1 was translocated to the nucleus in more than 90% and NUPR1 translocation was blocked by the ATZ-502 combination treatment in MDA-MB-231 with no change in NUPR1 expression, providing strong evidence that NUPR1 nuclear translocation was directly inhibited by the ATZ-502 treatment. Inhibition of KPNB1 and NUPR1 binding was associated with a synergistic anticancer effect (up to 19.6-fold) in various cancer cell lines. NUPR1-related genes were also downregulated following the doxorubicin–ATZ-502 combination treatment. Conclusion: Our current findings clearly demonstrate that NUPR1 translocation into the nucleus requires karyopherin β1 binding. Inhibition of the KPNB1 and NUPR1 interaction may constitute a new cancer therapeutic approach that can increase the drug efficacy while reducing the side effects.

Newly Developed Self-Assembling Antioxidants as Potential Therapeutics for the Cancers

Elevated reactive oxygen species (ROS) have been implicated as significant for cancer survival by functioning as oncogene activators and secondary messengers. Hence, the attenuation of ROS-signaling pathways in cancer by antioxidants seems a suitable therapeutic regime for targeting cancers. Low molecular weight (LMW) antioxidants such as 2,2,6,6-tetramethylpyperidine-1-oxyl (TEMPO), although they are catalytically effective in vitro, exerts off-target effects in vivo due to their size, thus, limiting their clinical use. Here, we discuss the superior impacts of our TEMPO radical-conjugated self-assembling antioxidant nanoparticle (RNP) compared to the LMW counterpart in terms of pharmacokinetics, therapeutic effect, and adverse effects in various cancer models.

Long noncoding RNA TCONS_00026334 is involved in suppressing the progression of colorectal cancer by regulating miR-548n/TP53INP1 signaling pathway

Recently, long noncoding RNAs (lncRNAs) were recognized as significant therapeutic targets in tumors. Our previous microarray analysis showed that lncRNA TCONS_000026334 expression was reduced in metastatic colorectal cancer (CRC) tissues. The objective of this study was to research the biological functions of TCONS_000026334 and the potential mechanism during the development of CRC. TCONS_00026334 transcription levels were detected in CRC tissues from 86 patients and different CRC cell lines. The clinical prognosis factors related to TCONS_00026334 expression were then analyzed. TCONS_000026334 was overexpressed from plasmid pcDNA3.1‐TCONS_ 000026334 or knocked down using a small interfering RNA (siRNA). Furthermore, bioinformatics approach and luciferase reporter gene assays were utilized to search for candidate miRNAs of TCONS_00026334 and identify the downstream target genes. The results indicated that TCONS_00026334 expression in 86 CRC tissues was markedly lower than that in non‐cancerous tissues. The aberrant expression of TCONS_00026334 correlated negatively with larger tumor size, distant metastasis, serological carcinoembryonic antigen level, and unfavorable survival of patients with CRC. TCONS_00026334 overexpression could inhibit the aggressive phenotypes of CRC in vitro and in vivo. Conversely, TCONS_00026334 silencing accelerated CRC cell proliferation and invasion. We then verified that TCONS_00026334 upregulated the expression level of TP53INP1, a target gene of miR‐548n, via direct binding to miR‐548n as a competing endogenous RNA. Taken together, our study showed that TCONS_00026334 acts as an anti‐tumor and anti‐metastatic gene by regulating the miR548n/TP53INP1 axis in the development of CRC.

Extra virgin olive oil and flaxseed oil have no preventive effects on DSS-induced acute ulcerative colitis

OBJECTIVES

The aim of this study was to evaluate the preventive effects of extra virgin olive oil (EVOO) or flaxseed oil (FO) on dextran sodium sulfate (DSS)-induced acute ulcerative colitis in female mice.

METHODS

Eighty C57BL/6J mice of 8-weeks-old were divided in four groups: Control (SO), 10%EVOO, 10%FO and 5%EVOO+5%FO. The oils were given through the AIN-93M diet. After 30 days, animals were divided in four more groups, in which half received 3%DSS in water for 5 days. Body weight loss, bleeding and stool consistency were verified for the Disease Activity Index (DAI). Animals were euthanized and their colon and spleen weighted and measured. Histopathological analysis, the concentrations of TNF-α, IL-1β, and IL-10 and the iNOS expression were evaluated in the colon samples.

RESULTS

Animals that received DSS presented with elevated disease activity index values; increased colon weight-to-length ratio; augmented leukocyte infiltration into the lamina propria and submucosa; and increased production of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6, and greater inducible nitric oxide synthase expression in the distal colon. Individually or in combination, the oils were not able to reverse or mitigate any of the DSS-induced symptoms or damage. Additionally, the group of animals treated with DSS and supplemented with FO displayed increased spleen weight-to-body weight ratio, and the group that received a combination of EVOO and FO presented increased TNF-α levels compared with the respective control group.

CONCLUSION

Consumption of large amounts of EVOO and FO as a treatment for or prevention against ulcerative colitis could potentially elicit unwanted adverse effects.

Tumor protein 53-induced nuclear protein 1 deficiency alters mouse gastrocnemius muscle function and bioenergetics in vivo

Tumor protein 53-induced nuclear protein 1 (TP53INP1) deficiency leads to oxidative stress-associated obesity and insulin resistance. Although skeletal muscle has a predominant role in the development of metabolic syndrome, the bioenergetics and functional consequences of TP53INP1 deficiency upon this tissue remain undocumented. To clarify this issue, gastrocnemius muscle mechanical performance, energy metabolism, and anatomy were investigated in TP53INP1-deficient and wild-type mice using a multidisciplinary approach implementing noninvasive multimodal-NMR techniques. TP53INP1 deficiency increased body adiposity but did not affect cytosolic oxidative stress, lipid content, and mitochondrial pool and capacity in myocyte. During a fatiguing bout of exercise, the in vivo oxidative ATP synthesis capacity was dramatically reduced in TP53INP1-deficient mice despite ADP level (the main in vivo stimulator of mitochondrial respiration) did not differ between both genotypes. Moreover, TP53INP1 deficiency did not alter fatigue resistance but paradoxically increased the contractile force, whereas there were no differences for muscle fiber-type distribution and calcium homeostasis between both genotypes. In addition, muscle proton efflux was decreased in TP53INP1-deficient mice, thereby indicating a reduced blood supply. In conclusion, TP53INP1 plays a role in muscle function and bioenergetics through oxidative capacity impairment possibly as the consequence of abnormal mitochondrial respiration regulation and/or defective blood supply.

Osteopontin Protects Colonic Mucosa from Dextran Sodium Sulfate-Induced Acute Colitis in Mice by Regulating Junctional Distribution of Occludin

BACKGROUND

Osteopontin (OPN) has been reported to play an important role in intestinal mucosal protection. Although OPN may have positive effects on tight junctions, the exact relationship between OPN and tight junctions has yet to be elucidated.

AIMS

To investigate the role of OPN on tight junctions.

METHODS

We evaluated clinical signs and histopathology of acute colitis induced by dextran sodium sulfate (DSS) in OPN knockout and wild-type (WT) mice in vivo. Expression levels of occludin and zonula occludens-1 were examined using immunofluorescence. For in vitro analysis, an siRNA-mediated OPN-suppressed Caco-2 monolayer was used. Expression levels and patterns of occludin were analyzed by immunofluorescence, and transepithelial electrical resistance (TER) was measured to evaluate barrier function. Triton X-100 fractionation was used to analyze phosphorylated occludin associated with tight junctional localization.

RESULTS

OPN deficiency resulted in an elevated disease activity index, shortened colon length, and aggravated histological signs in mice with DSS-induced acute colitis compared to WT mice. OPN deficiency decreased occludin expression in the colonic mucosa. In Caco-2 monolayers, OPN suppression reduced junctional occludin and redistributed it into the intracellular compartment with decreased TER. Furthermore, western blot for occludin from Triton X-100 insoluble fraction revealed that OPN suppression reduced the phosphorylated form of occludin, which is actually distributed in the tight junction.

CONCLUSIONS

Our study showed that OPN is essential for maintaining the tight junction complex by allowing occludin to localize at tight junctions. This could constitute additional evidence that OPN plays a crucial role in intestinal mucosal protection.

Dietary polysaccharide-rich extract from Eucheuma cottonii modulates the inflammatory response and suppresses colonic injury on dextran sulfate sodium-induced colitis in mice

Inflammatory bowel disease (IBD) is a known medical burden in most developed countries and a significant cause of morbidity. The IBD label includes Crohn's disease (CD) and ulcerative colitis (UC). Pharmacological and surgical intervention are the two main management approaches for IBD. Some drugs have been developed for IBD therapy, but accessibility is limited due to high costs. Furthermore, these agents have demonstrated inactivity over long-term treatment courses. Therefore, an urgent need is present for new treatment options that are safe, able to sustain clinical remission, and improve mucosal gut healing. Seaweed has received much attention in the pharmacological field owing to its various biomedical properties, including the prolongation of blood clotting time, as well as antitumor, anti-inflammation, and antioxidant effects. This study therefore aimed to examine the effects of a dietary polysaccharide-rich extract obtained from Eucheuma cottonii (EC) on a model of colitis. Colitis was induced in male BALB/c mice by the administration of 2.5% (w/v) dextran sulfate sodium (DSS) for 7 days. DSS-induced mice were treated with either one of three different doses of EC extracts (0.35, 0.70, and 1.75 g/kg body weight) or curcumin as a positive control (0.10 g/kg). Mice were sacrificed post-treatment and blood samples were collected. The disease activity index (DAI) and inflammatory cytokine levels (tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-10) were measured. After treatment for 7 days, EC extract administration protected against weight loss and decreased the colon weight per length ratio. EC extract administration also decreased pro-inflammatory cytokine expression, increased IL-10 levels, and reduced colonic damage. Therefore, a dietary polysaccharide-rich extract from E. cottonii reduced DSS-induced bowel inflammation, thereby becoming a promising candidate for the treatment of colitis.

Lack of Adrenomedullin Aggravates Acute TNBS-Induced Colitis Symptoms in Mice, Especially in Females

Adrenomedullin (AM) is a biologically active peptide which has been tested as a new therapy for inflammatory bowel disease (IBD) in animal models and in patients with severe ulcerative colitis. We used an inducible knockout (KO) mouse model for AM to evaluate the effects of endogenous levels of this peptide on the development and degree of pathogenesis of IBD. Acute colitis was induced in mice of both sexes by rectal instillation of 3 mg 2,4,6-trinitrobenzenesulfonic acid (TNBS) in 100 μL of 50% ethanol. Control mice received the same volume of saline in 50% ethanol. During the following 5 days, the weight and the disease severity index of all animals were recorded. After sacrifice, the inflammatory response was macroscopically assessed by analyzing the weight of the colon; by histomorphometrical analysis on histological sections; and by qRT-PCR determination of different inflammatory, adhesion, and regeneration molecules. TNBS administration caused a significantly more severe colitis in KO mice, and especially in females, when compared to wild type (WT) animals. Abrogation of the AM gene caused more severe diarrhea, accompanied by rectal bleeding, anorexia, and a significant increase of colon weight. Histological analysis of TNBS-treated KO mice showed large areas of lymphocyte infiltrates in the mucosa and submucosa, with loss of tissue architecture. No alterations were observed in the expression levels of inflammatory cytokines at the time of sacrifice; meanwhile lack of AM resulted in lower levels of some adhesion molecules and regeneration markers. Taken together, these results support the protective role of endogenous AM against the development of acute colitis, and that its effects are particularly beneficial on females.

Small molecules related to adrenomedullin reduce tumor burden in a mouse model of colitis-associated colon cancer

To investigate the contribution of adrenomedullin (AM) and its gene-related peptide, proadrenomedullin N-terminal 20 peptide (PAMP), to the progression and potential treatment of colon cancer we studied the effects of four small molecules (SM) related to AM and PAMP on a mouse model of colon cancer. For each SM, four experimental groups of male mice were used: (i) Control group; (ii) SM group; (iii) DSS group (injected with azoxymethane [AOM] and drank dextran sulfate sodium [DSS]); and (iv) DSS + SM group (treated with AOM, DSS, and the SM). None of the mice in groups i and ii developed tumors, whereas all mice in groups iii and iv developed colon neoplasias. No significant differences were found among mice treated with PAMP modulators (87877 and 106221). Mice that received the AM negative modulator, 16311, had worse colitis symptoms than their control counterparts, whereas mice injected with the AM positive modulator, 145425, had a lower number of tumors than their controls. SM 145425 regulated the expression of proliferation marker Lgr5 and had an impact on microbiota, preventing the DSS-elicited increase of the Bacteroides/Prevotella ratio. These results suggest that treatment with AM or with positive modulator SMs may represent a novel strategy for colon cancer.

Sphingomyelin synthase 2 deficiency inhibits the induction of murine colitis-associated colon cancer

Sphingomyelin synthase 2 (SMS2) is the synthetic enzyme of sphingomyelin (SM), which regulates membrane fluidity and microdomain structure. SMS2 plays a role in LPS-induced lung injury and inflammation; however, its role in inflammation-mediated tumorigenesis is unclear. We investigated the effect of SMS2 deficiency on dextran sodium sulfate (DSS)-induced murine colitis and found inhibition of DSS-induced inflammation in SMS2-deficient (SMS2-/-) mice. DSS treatment induced a significant increase in ceramide levels, with a decrease of SM levels in SMS2-/- colon tissue, and demonstrated attenuation of the elevation of both inflammation-related gene expression and proinflammatory cytokines and chemokines, leukocyte infiltration, and MAPK and signal transducer and activator of transcription 3 activation. After undergoing transplantation of wild-type bone marrow, SMS2-/- mice also exhibited inhibition of DSS-induced inflammation in the colon, which suggested that SMS2 deficiency in bone marrow-derived immune cells was not involved in the inhibition of colitis. Finally, in an azoxymethane/DSS-induced cancer model, SMS2 deficiency significantly decreased tumor incidence in the colon. Our results demonstrate that SMS2 deficiency inhibits DSS-induced colitis and subsequent colitis-associated colon cancer via inhibition of colon epithelial cell-mediated inflammation; therefore, inhibition of SMS2 may be a potential therapeutic target for human colitis and colorectal cancer.-Ohnishi, T., Hashizume, C., Taniguchi, M., Furumoto, H., Han, J., Gao, R., Kinami, S., Kosaka, T., Okazaki, T. Sphingomyelin synthase 2 deficiency inhibits the induction of murine colitis-associated colon cancer.

TP53INP1 Downregulation Activates a p73-Dependent DUSP10/ERK Signaling Pathway to Promote Metastasis of Hepatocellular Carcinoma

Identifying critical factors involved in the metastatic progression of hepatocellular carcinoma (HCC) may offer important therapeutic opportunities. Here, we report that the proapoptotic stress response factor TP53INP1 is often selectively downregulated in advanced stage IV and metastatic human HCC tumors. Mechanistic investigations revealed that TP53INP1 downregulation in early-stage HCC cells promoted metastasis via DUSP10 phosphatase-mediated activation of the ERK pathway. The DUSP10 promoter included putative binding sites for p73 directly implicated in modulation by TP53INP1. Overall, our findings show how TP53INP1 plays a critical role in limiting the progression of early-stage HCC, with implications for developing new therapeutic strategies to attack metastatic HCC. Cancer Res; 77(17); 4602-12. ©2017 AACR.

Downregulation of tumor protein 53-inducible nuclear protein 1 expression in hepatocellular carcinoma correlates with poor prognosis

The expression of tumor protein 53-inducible nuclear protein 1 (TP53INP1) is upregulated in certain cancers and downregulated in others. However, its expression in hepatocellular carcinoma (HCC) is not clear. The present study aimed to investigate the expression and prognostic value of TP53INP1 and its association with clinicopathological parameters in HCC. TP53INP1 expression in HCC tissue samples was examined via immunohistochemistry, western blotting and reverse transcription-quantitative polymerase chain reaction. Expression was categorized as high or low. The correlations of TP53INP1 expression with clinical characteristics and patients' prognoses were determined. TP53INP1 was frequently decreased in HCC tissues compared with adjacent non-tumorous liver tissues. This decreased expression was significantly associated with American Joint Committee on Cancer stage (P=0.014) and vascular invasion (P=0.024). Kaplan-Meier analysis further revealed that recurrence-free survival (RFS) (P=0.001) and overall survival (OS) (P=0.002) were significantly worse among patients with low TP53INP1 expression than among those with high TP53INP1 expression. In addition, multivariate analyses revealed that TP53INP1 was an independent predictor of OS [hazard ratio (HR)=2.680, 95% confidence interval (CI)=1.087–6.608, P=0.032) and RFS (HR=2.284, 95% CI=1.157–4.511, P=0.017). In conclusion, the expression of TP53INP1 was decreased in HCC, and TP53INP1 downregulation was an independent predictor of poor prognosis in patients with HCC.

Lack of Adrenomedullin Results in Microbiota Changes and Aggravates Azoxymethane and Dextran Sulfate Sodium-Induced Colitis in Mice

The link between intestinal inflammation, microbiota, and colorectal cancer is intriguing and the potential underlying mechanisms remain unknown. Here we evaluate the influence of adrenomedullin (AM) in microbiota composition and its impact on colitis with an inducible knockout (KO) mouse model for AM. Microbiota composition was analyzed in KO and wild type (WT) mice by massive sequencing. Colitis was induced in mice by administration of azoxymethane (AOM) followed by dextran sulfate sodium (DSS) in the drinking water. Colitis was evaluated using a clinical symptoms index, histopathological analyses, and qRT-PCR. Abrogation of the adm gene in the whole body was confirmed by PCR and qRT-PCR. KO mice exhibit significant changes in colonic microbiota: higher proportion of δ-Proteobacteria class; of Coriobacteriales order; and of other families and genera was observed in KO feces. Meanwhile these mice had a lower proportion of beneficial bacteria, such as Lactobacillus gasseri and Bifidobacterium choerinum. TLR4 gene expression was higher (p < 0.05) in KO animals. AM deficient mice treated with DSS exhibited a significantly worse colitis with profound weight loss, severe diarrhea, rectal bleeding, colonic inflammation, edema, infiltration, crypt destruction, and higher levels of pro-inflammatory cytokines. No changes were observed in the expression levels of adhesion molecules. In conclusion, we have shown that lack of AM leads to changes in gut microbiota population and in a worsening of colitis conditions, suggesting that endogenous AM is a protective mediator in this pathology.

A Novel Role of Spred2 in the Colonic Epithelial Cell Homeostasis and Inflammation

Rapid and adequate mucosal healing is important for a remission of ulcerative colitis (UC) patients. Here, we examined whether Spred2, a member of the Sprouty-related EVH1-domain-containing proteins that inhibit the Ras/Raf/ERK pathway, plays a role in colonic mucosal homeostasis and inflammation by using Spred2 knockout (KO) mice. We first detected increased epithelial cell proliferation and cadherin 1 expression in the colon of naïve Spred2 KO mice compared to wild-type mice. Interestingly, Spred2 KO mice were resistant to dextran sulfate sodium (DSS)-induced acute colitis as indicated by lower levels of body weight loss and disease activity index. Histologically, epithelial cell injury and inflammation were milder in the colonic mucosa of Spred2 KO mice on day 3 and almost undetectable by day 8. Experiments with bone chimeric mice indicated that Spred2-deficiency in non-hematopoietic cells was responsible for the reduced sensitivity to DSS. Finally, Spred2 KO mice developed significantly fewer tumors in response to azoxymethane plus DSS. Taken together, our results demonstrate, for the first time, that Spred2 plays an important role in the regulation of colonic epithelial cell proliferation and inflammation by potentially down-regulating the activation of ERK. Thus, Spred2 may be a new therapeutic target for the treatment of UC.

Defects in mitophagy promote redox-driven metabolic syndrome in the absence of TP53INP1

The metabolic syndrome covers metabolic abnormalities including obesity and type 2 diabetes (T2D). T2D is characterized by insulin resistance resulting from both environmental and genetic factors. A genome-wide association study (GWAS) published in 2010 identified TP53INP1 as a new T2D susceptibility locus, but a pathological mechanism was not identified. In this work, we show that mice lacking TP53INP1 are prone to redox-driven obesity and insulin resistance. Furthermore, we demonstrate that the reactive oxygen species increase in TP53INP1-deficient cells results from accumulation of defective mitochondria associated with impaired PINK/PARKIN mitophagy. This chronic oxidative stress also favors accumulation of lipid droplets. Taken together, our data provide evidence that the GWAS-identified TP53INP1 gene prevents metabolic syndrome, through a mechanism involving prevention of oxidative stress by mitochondrial homeostasis regulation. In conclusion, this study highlights TP53INP1 as a molecular regulator of redox-driven metabolic syndrome and provides a new preclinical mouse model for metabolic syndrome clinical research.

The matricellular protein CCN1 promotes mucosal healing in murine colitis through IL-6

The matricellular protein CCN1 (CYR61) is known to function in wound healing and is upregulated in colons of patients with Crohn's disease and ulcerative colitis, yet its specific role in colitis is unknown. Here we have used Ccn1(dm/dm) knockin mice expressing a CCN1 mutant unable to bind integrins α6β1 and αMβ2 as a model to probe CCN1 function in dextran sodium sulfate (DSS)-induced colitis. Ccn1(dm/dm) mice exhibited high mortality, impaired mucosal healing, and diminished interleukin-6 (IL-6) expression during the repair phase of DSS-induced colitis compared with wild-type mice, despite having comparable severity of initial inflammation and tissue injury. CCN1-induced IL-6 expression in macrophages through integrin αMβ2 and in fibroblasts through α6β1, and IL-6 promoted intestinal epithelial cell (IEC) proliferation. Administration of purified CCN1 protein fully rescued Ccn1(dm/dm) mice from DSS-induced mortality, restored IEC proliferation and enhanced mucosal healing, whereas delivery of IL-6 partially rectified these defects. CCN1 therapy accelerated mucosal healing and recovery from DSS-induced colitis even in wild-type mice. These findings reveal a critical role for CCN1 in restoring mucosal homeostasis after intestinal injury in part through integrin-mediated induction of IL-6 expression, and suggest a therapeutic potential for activating the CCN1/IL-6 axis for treating inflammatory bowel disease.

A positive feedback loop of p53/miR-19/TP53INP1 modulates pancreatic cancer cell proliferation and apoptosis

Pancreatic cancer is a common malignancy whose prognosis and treatment of pancreatic cancer is extremely poor, with only 20% of patients reaching two years of survival. Previous findings have shown that the tumor suppressor p53 is involved in the development of various types of cancer, including pancreatic cancer. Additionally, p53 is able to activate TP53INP1 transcription by regulating several phenotypes of cancer cells. Using gain and loss-of-function assays, the aim of the present study was to examine the relationships between miR-19a/b and cancer development as well as potential underlying mechanisms. The results showed that miR-19a/b identified a positive feedback regulation of p53/TP53INP1 axis. Additionally, p53 upregulated the TP53INP1 level in pancreatic cancer cells. However, overexpressed miR-19a/b partially restored the TP53 function in the pancreatic cancer cells while miR-19a/b downregulated TP53INP1 protein by directly targeting 3'UTR of its mRNA at the post-transcriptional level. In addition, the patient tissues identified that the miR-19a/b level in pancreatic cancer tissues was conversely correlated with TP53 and TP53INP1 expression. The results provide evidence for revealing the molecular mechanism involved in the development of pancreatic cancer and may be useful in the identification of new therapeutic targets for pancreatic cancer.

TP53inp1 Gene Is Implicated in Early Radiation Response in Human Fibroblast Cells

Tumor protein 53-induced nuclear protein-1 (TP53inp1) is expressed by activation via p53 and p73. The purpose of our study was to investigate the role of TP53inp1 in response of fibroblasts to ionizing radiation. γ-Ray radiation dose-dependently induces the expression of TP53inp1 in human immortalized fibroblast (F11hT) cells. Stable silencing of TP53inp1 was done via lentiviral transfection of shRNA in F11hT cells. After irradiation the clonogenic survival of TP53inp1 knockdown (F11hT-shTP) cells was compared to cells transfected with non-targeting (NT) shRNA. Radiation-induced senescence was measured by SA-β-Gal staining and autophagy was detected by Acridine Orange dye and microtubule-associated protein-1 light chain 3 (LC3B) immunostaining. The expression of TP53inp1, GDF-15, and CDKN1A and alterations in radiation induced mitochondrial DNA deletions were evaluated by qPCR. TP53inp1 was required for radiation (IR) induced maximal elevation of CDKN1A and GDF-15 expressions. Mitochondrial DNA deletions were increased and autophagy was deregulated following irradiation in the absence of TP53inp1. Finally, we showed that silencing of TP53inp1 enhances the radiation sensitivity of fibroblast cells. These data suggest functional roles for TP53inp1 in radiation-induced autophagy and survival. Taken together, we suppose that silencing of TP53inp1 leads radiation induced autophagy impairment and induces accumulation of damaged mitochondria in primary human fibroblasts.

Mammalian models of chemically induced primary malignancies exploitable for imaging-based preclinical theragnostic research

Compared with transplanted tumor models or genetically engineered cancer models, chemically induced primary malignancies in experimental animals can mimic the clinical cancer progress from the early stage on. Cancer caused by chemical carcinogens generally develops through three phases namely initiation, promotion and progression. Based on different mechanisms, chemical carcinogens can be divided into genotoxic and non-genotoxic ones, or complete and incomplete ones, usually with an organ-specific property. Chemical carcinogens can be classified upon their origins such as environmental pollutants, cooked meat derived carcinogens, N-nitroso compounds, food additives, antineoplastic agents, naturally occurring substances and synthetic carcinogens, etc. Carcinogen-induced models of primary cancers can be used to evaluate the diagnostic/therapeutic effects of candidate drugs, investigate the biological influential factors, explore preventive measures for carcinogenicity, and better understand molecular mechanisms involved in tumor initiation, promotion and progression. Among commonly adopted cancer models, chemically induced primary malignancies in mammals have several advantages including the easy procedures, fruitful tumor generation and high analogy to clinical human primary cancers. However, in addition to the time-consuming process, the major drawback of chemical carcinogenesis for translational research is the difficulty in noninvasive tumor burden assessment in small animals. Like human cancers, tumors occur unpredictably also among animals in terms of timing, location and the number of lesions. Thanks to the availability of magnetic resonance imaging (MRI) with various advantages such as ionizing-free scanning, superb soft tissue contrast, multi-parametric information, and utility of diverse contrast agents, now a workable solution to this bottleneck problem is to apply MRI for noninvasive detection, diagnosis and therapeutic monitoring on those otherwise uncontrollable animal models with primary cancers. Moreover, it is foreseeable that the combined use of chemically induced primary cancer models and molecular imaging techniques may help to develop new anticancer diagnostics and therapeutics.

The stress protein TP53INP1 plays a tumor suppressive role by regulating metabolic homeostasis

In the recent years, we have provided evidence that Tumor Protein 53-Induced Nuclear Protein 1 (TP53INP1) is a key stress protein with antioxidant-associated tumor suppressive function. The TP53INP1 gene, which is highly conserved in mammals, is over-expressed during stress responses including inflammation. This gene encodes two protein isoforms with nuclear or cytoplasmic subcellular localization depending on the context. TP53INP1 contributes to stress responses, thus preventing stress-induced dysfunctions leading to pathologies such as cancer. Two major mechanisms by which TP53INP1 functions have been unveiled. First, in the nucleus, TP53INP1 was shown to regulate the transcriptional activity of p53 and p73 by direct interaction, and to mediate the antioxidant activity of p53. Second, independently of p53, TP53INP1 contributes to autophagy and more particularly mitophagy through direct interaction with molecular actors of autophagy. TP53INP1 is thus required for the homeostasis of the mitochondrial compartment, and is therefore involved in the regulation of energetic metabolism. Finally, the antioxidant function of TP53INP1 stems from the control of mitochondrial reactive oxygen species production. In conclusion, TP53INP1 is a multifaceted protein endowed with multiple functions, including metabolic regulation, as is its main functional partner p53.

Inhibition of chronic ulcerative colitis-associated adenocarcinoma development in mice by VSL#3

BACKGROUND

Colorectal cancer is the most severe complication in inflammatory bowel disease. This study aimed to investigate the effects of the probiotic VSL#3 when administered as either preventive or concurrent treatment in the progression from chronic colitis to colon cancer.

METHODS

Mice were exposed to 5, 10, and 15 cycles of dextran sulfate sodium (DSS); each cycle consisted of 0.7% DSS for 1 week followed by distilled water for 10 days. VSL#3 was administered either from 2 weeks before the colitis induction or from the first day of the colitis until being killed. After each period, macroscopic and histological studies, as well as analysis of inflammatory and tumor biomarkers, were performed.

RESULTS

Prophylactic or concurrent VSL#3 administration attenuated the disease activity index score and colon inflammation after 5, 10, and 15 cycles of DSS, as well as reduced the histological alterations and the incidence of colonic dysplastic lesions at the 3 periods studied. None of the animals receiving VSL#3 as a concurrent treatment developed carcinoma, which is in contrast to 5% and 20% of the mice following preventive VSL#3 administration, developing carcinoma at the 10th and the 15th cycles of DSS, respectively. In addition, the probiotic reduced the proliferating cell nuclear antigen labeling index, tumor necrosis factor alpha, interleukin-1β, interleukin-6 production, cyclooxygenase-2 expression, and increased interleukin-10 levels in colon tissue at the 3 periods assayed.

CONCLUSIONS

VSL#3 administration reduced chronic inflammation and prevented or delayed the development of dysplasia and carcinoma in a mouse model of chronic colitis-associated cancer.

Development of an oral nanotherapeutics using redox nanoparticles for treatment of colitis-associated colon cancer

Oral chemotherapy is the preferred treatment for colon cancer. However, this strategy faces many challenges, including instability in the gastrointestinal (GI) tract, insufficient bioavailability, low tumor targeting, and severe adverse effects. In this study, we designed a novel redox nanoparticle (RNP(O)) that is an ideal oral therapeutics for colitis-associated colon cancer treatment. RNP(O) possesses nitroxide radicals in the core, which act as reactive oxygen species (ROS) scavengers. Orally administered RNP(O) highly accumulated in colonic mucosa, and specifically internalized in cancer tissues, but less in normal tissues. Despite of long-term oral administration of RNP(O), no noticeable toxicities were observed in major organs of mice. Because RNP(O) effectively scavenged ROS, it significantly suppressed tumor growth after accumulation at tumor sites. Combination of RNP(O) with the conventional chemotherapy, irinotecan, led to remarkably improved therapeutic efficacy and effectively suppressed its adverse effects on GI tract. Therefore, RNP(O) is promising oral nanotherapeutics for cancer therapies.

Redox-sensitive TP53INP1 SUMOylation as an oxidative stress sensor to activate TP53

Oxidative stress-induced sumoylation of TP53INP1 (tumor protein p53-induced nuclear protein 1) is essential to enhance the TP53 response. Sumoylation of TP53INP1 on the K113 residue, which is mediated by protein inhibitor of activated STAT 3 (PIAS3) and chromobox homolog 4 (CBX4) and removed by SUMO1/sentrin specific peptidase (SENP1, 2 and 6), favors its interaction with TP53 in the nucleus and enhances TP53-induced gene expression.

Copy number gain of hsa-miR-569 at 3q26.2 leads to loss of TP53INP1 and aggressiveness of epithelial cancers

Small noncoding miRNAs represent underexplored targets of genomic aberrations and emerging therapeutic targets. The 3q26.2 amplicon is among the most frequent genomic aberrations in multiple cancer lineages including ovarian and breast cancers. We demonstrate that hsa-miR-569 (hereafter designated as miR569), which is overexpressed in a subset of ovarian and breast cancers, at least in part due to the 3q26.2 amplicon, alters cell survival and proliferation. Downregulation of TP53INP1 expression by miR569 is required for the effects of miR569 on survival and proliferation. Targeting miR569 sensitizes ovarian and breast cancer cells overexpressing miR569 to cisplatin by increasing cell death both in vitro and in vivo. Thus targeting miR569 could potentially benefit patients with the 3q26.2 amplicon and subsequent miR569 elevation.

The Trp53-Trp53inp1-Tnfrsf10b pathway regulates the radiation response of mouse spermatogonial stem cells

Germ cells are thought to exhibit a unique DNA damage response that differs from that of somatic stem cells, and previous studies suggested that Trp53 is not involved in the survival of spermatogonial stem cells (SSCs) after irradiation. Here, we report a critical role for the Trp53-Trp53inp1-Tnfrsf10b pathway during radiation-induced SSC apoptosis. Spermatogonial transplantation revealed that Trp53 deficiency increased the survival of SSCs after irradiation. Although Bbc3, a member of the intrinsic apoptotic pathway, was implicated in apoptosis of germ and somatic stem cells, Bbc3 depletion inhibited apoptosis in committed spermatogonia, but not in SSCs. In contrast, inhibition of Tnfrsf10b, an extrinsic apoptosis regulator, rescued SSCs. Tnfrsf10b, whose deficiency protected SSCs, was upregulated by Trp53inp1 upon irradiation. These results suggest that the Trp53-Trp53inp1-Tnfrsf10b pathway responds to genotoxic damage in SSCs and that stem and progenitor cells exhibit distinct DNA damage responses in self-renewing tissue.

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Trp53 induces radiation-induced apoptosis of spermatogonial stem cells (SSCs)

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Bbc3 induces radiation-induced apoptosis of spermatogonial progenitors

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Tnfsf10 is induced in spermatogonia and the SSC microenvironment

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Trp53inp1 upregulates Tnfrsf10b and induces SSC apoptosis upon irradiation

Genetic inactivation of Nupr1 acts as a dominant suppressor event in a two-hit model of pancreatic carcinogenesis

BACKGROUND

Nuclear protein 1 (Nupr1) is a major factor in the cell stress response required for Kras(G12D)-driven formation of pancreatic intraepithelial neoplastic lesions (PanINs). We evaluated the relevance of Nupr1 in the development of pancreatic cancer.

METHODS

We investigated the role of Nupr1 in pancreatic ductal adenocarcinoma (PDAC) progression beyond PanINs in Pdx1-cre;LSL-Kras(G12D);Ink4a/Arf(fl/fl)(KIC) mice.

RESULTS

Even in the context of the second tumorigenic hit of Ink4a/Arf deletion, Nupr1 deficiency led to suppression of malignant transformation involving caspase 3 activation in premalignant cells of KIC pancreas. Only half of Nupr1-deficient;KIC mice achieved PDAC development, and incident cases survived longer than Nupr1(wt);KIC mice. This was associated with the development of well-differentiated PDACs in Nupr1-deficient;KIC mice, which displayed enrichment of genes characteristic of the recently identified human classical PDAC subtype. Nupr1-deficient;KIC PDACs also shared with human classical PDACs the overexpression of the Kras-activation gene signature. In contrast, Nupr1(wt);KIC mice developed invasive PDACs with enriched gene signature of human quasi-mesenchymal (QM) PDACs. Cells derived from Nupr1-deficient;KIC PDACs growth in an anchorage-independent manner in vitro had higher aldehyde dehydrogenase activity and overexpressed nanog, Oct-4 and Sox2 transcripts compared with Nupr1(wt);KIC cells. Moreover, Nupr1-deficient and Nurpr1(wt);KIC cells differed in their sensitivity to the nucleoside analogues Ly101-4b and WJQ63. Together, these findings show the pivotal role of Nupr1 in both the initiation and late stages of PDAC in vivo, with a potential impact on PDAC cell stemness.

CONCLUSIONS

According to Nupr1 status, KIC mice develop tumours that phenocopy human classical or QM-PDAC, respectively, and present differential drug sensitivity, thus becoming attractive models for preclinical drug trials.

Oxidative stress-induced p53 activity is enhanced by a redox-sensitive TP53INP1 SUMOylation

Tumor Protein p53-Induced Nuclear Protein 1 (TP53INP1) is a tumor suppressor that modulates the p53 response to stress. TP53INP1 is one of the key mediators of p53 antioxidant function by promoting the p53 transcriptional activity on its target genes. TP53INP1 expression is deregulated in many types of cancers including pancreatic ductal adenocarcinoma in which its decrease occurs early during the preneoplastic development. In this work, we report that redox-dependent induction of p53 transcriptional activity is enhanced by the oxidative stress-induced SUMOylation of TP53INP1 at lysine 113. This SUMOylation is mediated by PIAS3 and CBX4, two SUMO ligases especially related to the p53 activation upon DNA damage. Importantly, this modification is reversed by three SUMO1-specific proteases SENP1, 2 and 6. Moreover, TP53INP1 SUMOylation induces its binding to p53 in the nucleus under oxidative stress conditions. TP53INP1 mutation at lysine 113 prevents the pro-apoptotic, antiproliferative and antioxidant effects of TP53INP1 by impairing the p53 response on its target genes p21, Bax and PUMA. We conclude that TP53INP1 SUMOylation is essential for the regulation of p53 activity induced by oxidative stress.

The role of reactive oxygen species and metabolism on cancer cells and their microenvironment

Compelling evidence show that reactive oxygen species (ROS) levels are finely regulated in the cell and can act as "second messengers" in response to diverse stimuli. In tumor epithelial cells, ROS accumulate abnormally and induce signaling cascades that mediate the oncogenic phenotype. In addition to their impact on tumor epithelial cells, ROS also affect the surrounding cells that constitute the tumor microenvironment. Indeed, ROS production increases tumor angiogenesis, drives the onset of inflammation and promotes conversion of fibroblast into myofibroblasts. These cells, initially identified upon wound healing, exhibit similar properties to those observed in fibroblasts associated with aggressive adenocarcinomas. Indeed, analyses of tumors with distinct severity revealed the existence of multiple distinct co-existing subtypes of carcinoma-associated fibroblasts (CAFs), with specific marker protein profiling. Chronic oxidative stress deeply modifies the proportion of these different fibroblast subtypes, further supporting tumor growth and metastatic dissemination. At last, ROS have been implicated in the metabolic reprogramming of both cancer cells and CAFs, allowing an adaptation to oxidative stress that ultimately promotes tumorigenesis and chemoresistance. In this review, we discuss the role of ROS in cancer cells and CAFs and their impact on tumor initiation, progression, and metastasis.

Role of miR-19a targeting TNF-α in mediating ulcerative colitis

OBJECTIVE

Ulcerative colitis (UC) is a widely studied inflammatory disease associated with differential expression of genes involved in immune function, wound healing, and tissue remodeling. MicroRNAs have been reported to play a role in various cancer types. However, the mechanism of how microRNAs regulate UC remains unclear.

METHODS

In the present study, we investigated the role of miR-19a and tumor necrosis factor (TNF)-α in human colon tissues with UC and dextran sodium sulfate (DSS)-induced experimental colitis.

RESULTS

We identified that the expression of miR-19a was significantly reduced and TNF-α was remarkably increased in human colon tissue with UC. Moreover, this observation of miR-19a and TNF-α was also occurred in DSS-treated mice colitis. Further, we observed that miR-19a directly regulated TNF-α expression because miR-19a can suppress the expression of wild-type TNF-α reporter, but not the mutant form. The expression of inflammatory factors TNF-α, IL-8, and GM-GSF were significantly elevated upon application of miR-19a inhibitor.

CONCLUSION

Taken together, this study determines the levels of miR-19a and TNF-α in both DSS-induced experimental murine colitis and human UC and further demonstrates that miR-19a might directly regulate TNF-α. The findings may provide a new insight in the clinical treatment of UC.

Development of an ELISA detecting Tumor Protein 53-Induced Nuclear Protein 1 in serum of prostate cancer patients

Tumor Protein 53-Induced Nuclear Protein 1 (TP53INP1) plays an important role during cell stress response in synergy with the potent "genome-keeper" p53. In human, the gene encoding TP53INP1 is expressed at very high level in some pathological situations, such as inflammation and prostate cancer (PC). TP53INP1 overexpression in PC seems to be a worse prognostic factor, particularly predictive of biological cancer relapse, making TP53INP1 a relevant specific target for molecular therapy of Castration Resistant (CR) PC. In that context, detection of TP53INP1 in patient biological fluids is a promising diagnostic avenue. We report here successful development of a new Enzyme-Linked Immunosorbent Assay (ELISA) detecting TP53INP1, taking advantage of molecular tools (monoclonal antibodies (mAbs) and recombinant proteins) generated in the laboratory during the course of basic functional investigations devoted to TP53INP1. The ELISA principle is based on a sandwich immunoenzymatic system, TP53INP1 protein being trapped by a first specific mAb coated on microplate then recognized by a second specific mAb. This new assay allows specific detection of TP53INP1 in serum of several PC patients. This breakthrough paves the way towards investigation of a large cohort of patients and assessment of clinical applications of TP53INP1 dosage.

Oxidative stress induced by inactivation of TP53INP1 cooperates with KrasG12D to initiate and promote pancreatic carcinogenesis in the murine pancreas

Tumor protein p53-induced nuclear protein 1 (TP53INP1) is involved in cell stress response. Its expression is lost at the pancreatic intraepithelial neoplasia 1b (PanIN1b)/PanIN2 stage of pancreatic carcinogenesis. Our objective was to determine whether TP53INP1 loss of expression contributes to pancreatic cancer formation in a conditional KrasG12D mouse model. We generated Kras-INP1KO mice using LSL-Kras(G12D/+);Pdx1-Cre(+/-) mice (Kras mice) and TP53INP1(-/-) mice. Analysis of pancreases during ageing shows that in the presence of activated Kras, TP53INP1 loss of expression accelerated PanIN formation and increased pancreatic injury and the number of high-grade lesions as compared with what occurs in Kras mice. Moreover, cystic lesions resembling intraductal papillary mucinous neoplasm (IPMN) were observed as early as 2 months of age. Remarkably, TP53INP1 is down-regulated in human IPMN. Activation of the small GTPase Rac1 shows that more oxidative stress is generated in Kras-INP1KO than in Kras mice pancreas despite elevated levels of the Nrf2 antioxidant regulator. We firmly establish the link between Kras-INP1KO pancreatic phenotype and oxidative stress with rescue of the phenotype by the antioxidant action of N-acetylcysteine. Our data provide in vivo functional demonstration that TP53INP1 deficiency accelerates progression of pancreatic cancer, underlining its role in the occurrence of IPMN and highlighting the importance of TP53INP1 in the control of oxidative status during development of pancreatic cancer.

TP53INP1 as new therapeutic target in castration-resistant prostate cancer

BACKGROUND

Prostate cancer (PC) is one of the most common malignancies in industrialized countries, and the second leading cause of cancer-related death in the United States. We recently showed that over-expression of tumor protein 53-induced nuclear protein 1 (TP53INP1), a cell stress response protein, is a worse prognostic factor in PC, particularly predictive of biological cancer relapse. Moreover, treatment of castration-sensitive (CS) LNCaP tumor cells with a TP53INP1 antisense oligonucleotide (TP53INP1 ASO) inhibits proliferation and induces apoptosis. The aim of this study was to investigate variations of TP53INP1 expression in PC during androgen withdrawal therapy and in castration-resistant prostate cancer (CRPC).

METHODS

Quantitative measurements of immunohistochemical expression of TP53INP1 using high-throughput densitometry, assessed on digitized microscopic tissue micro-array images were correlated with hormone therapy (HT) status in human PC. Northern blot analysis of TP53INP1 after castration was performed in LNCaP xenograft. Treatment of CR C4-2 tumor cells in vitro with TP53INP1 ASO was analyzed. We also analyzed the effect of TP53INP1 ASO treatment in vivo on tumor xenograft growth.

RESULTS

TP53INP1 protein expression decreases during HT and increases after HT in human CRPC. TP53INP1 mRNA increases significantly in CR tumors of LNCaP xenograft. Moreover, treatment of CR C4-2 cells with TP53INP1 ASO downregulates TP53INP1 protein level, inhibits proliferation, and induces apoptosis. Finally, in vivo, TP53INP1 ASO treatment significantly inhibits the tumoral progression of CR C4-2 xenograft and enhances docetaxel cytotoxicity.

CONCLUSIONS

These results suggest that TP53INP1 could be considered as a relevant-specific target for molecular therapy of CRPC.

Meaning of tumor protein 53-induced nuclear protein 1 in the molecular mechanism of gemcitabine sensitivity

Stress proteins of the pancreas, such as tumor protein 53-induced nuclear protein 1 (TP53INP1), are important factors in the invasion and metastasis of pancreatic cancer. TP53INP1 is a pro-apoptotic factor and is transcriptionally regulated in p53-dependent and -independent manners. A previous study proved that gemcitabine induces TP53INP1 expression in pancreatic cancer cells and the pancreatic cancer cell line (PANC-1). The present study aimed to clarify the association between TP53INP1 and gemcitabine sensitivity. The expression of TP53INP1 and its related factors, such as cell growth and cell cycle status in TP53INP1-knockout mouse embryonic fibroblasts [TP53INP1^-/--mouse embryonic fibroblasts (MEFs)] to those in wild-type counterparts (TP53INP1^+/+-MEFs) were compared. Flow cytometric analysis demonstrated no difference of the checkpoint function in TP53INP1^-/--MEFs and TP53INP1^+/+-MEFs when exposed to 10 ng/ml of gemcitabine. No significant difference was found in the level of p53 expression in the cell types, although the base level and gemcitabine-induced expression of p21 were significantly decreased in TP53INP1^-/--MEFs, compared to those in wild-type counterparts. Results showed that gemcitabine induced the p21 expression in TP53INP1^+/+-MEFs, although not in TP53INP1^-/--MEFs. However, their respective cell-cycle checkpoints were not different. Therefore, TP53INP1 was found to be associated with drug sensitivity through control of the cell cycle.

Homotypic cell cannibalism, a cell-death process regulated by the nuclear protein 1, opposes to metastasis in pancreatic cancer

Pancreatic adenocarcinoma (PDAC) is an extremely deadly disease for which all treatments available have failed to improve life expectancy significantly. This may be explained by the high metastatic potential of PDAC cells, which results from their dedifferentiation towards a mesenchymal phenotype. Some PDAC present cell-in-cell structures whose origin and significance are currently unknown. We show here that cell-in-cells form after homotypic cell cannibalism (HoCC). We found PDAC patients whose tumours display HoCC develop less metastasis than those without. In vitro, HoCC was promoted by inactivation of the nuclear protein 1 (Nupr1), and was enhanced by treatment with transforming growth factor β. HoCC ends with death of PDAC cells, consistent with a metastasis suppressor role for this phenomenon. Hence, our data indicates a protective role for HoCC in PDAC and identifies Nupr1 as a molecular regulator of this process.