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A 67-year-old woman presented with painful, acute vision loss after 5 days of fever and muscle aches while visiting the Dominican Republic. She had no recent history of ocular surgery, dental work or recent trauma. Anterior chamber aspiration confirmed an initial diagnosis of endogenous endophthalmitis, positive for Streptococcus mitis that progressed to panophthalmitis on return to Canada. Treatment included systemic antibiotics, intravitreal antibiotics and intravitreal dexamethasone. Despite the best medical treatment, the left eye progressed to corneal perforation 5 weeks after presentation. An evisceration with fitted orbital implant was successful in alleviating pain following the surgery. S. mitis is a rare, but possible cause of endogenous endophthalmitis and panophthalmitis. It was important to work with a multidisciplinary and global team to coordinate and offer appropriate treatment measures. Although vision was lost, evisceration of the left eye provided ocular comfort and good cosmetic outcomes for the patient.

Myositis-specific antibodies (MSAs) facilitate grouping children with juvenile dermatomyositis (DM) into distinct phenotypes. The first aim of this study was to investigate the link between anti-p155/140 and lipodystrophy as determined by dual x-ray absorptiometry (DXA) assessment of fat distribution. The second aim was to examine the relationship between anti-p155/140 and damage to the nailfold capillary system.Children with juvenile DM followed for a minimum of 5 years were included. The study population was divided into 3 groups (anti-p155/140, other MSA, and MSA negative). Lipodystrophy was assessed by physician assessment and DXA fat distribution (trunk-to-leg fat ratio). Documentation of nailfold capillary end row loops (ERLs) was obtained at diagnosis.A total of 96 subjects (44% anti-p155/140, 23% other MSA, 33% MSA negative) were included. There was no significant difference in age, disease activity scores, or lipodystrophy between the 3 groups. The trunk-to-leg fat ratios were similar among the 3 groups at different time points. However, the anti-p155/140 group had significantly decreased ERL counts (P = 0.006) at baseline as well as a prolonged duration of untreated disease at diagnosis (P = 0.027). Also, the anti-p155/140 group had fewer patients with a monophasic disease course than the other 2 groups (P = 0.008).Generalized lipodystrophy frequency was equivalent in all 3 groups based on physician assessments and trunk-to-leg fat ratios. The anti-p155/140 group had a greater loss of ERLs, suggesting that this MSA may impact the vascular component of juvenile DM.

Purpose The purpose of this paper is to evaluate leadership training in the Sandwich Glaucoma Fellowship (SGF), a program in which fellows learn skills in a developed world institution and their home country to become leaders in glaucoma care. Design/methodology/approach This paper is a retrospective, qualitative and quantitative evaluation. Participants of the SGF between 2007 and 2019 were provided a survey eliciting demographic information, leadership training exposure, development of leadership competencies and feedback for the fellowship program. Findings Seven of nine alumni responded. The fellowship strongly impacted leadership competencies including integrity (8.8, 95% CI 7.8–9.8), work ethic (8.64, 95% CI 7.7–9.6) and empathy (8.6, 95% CI 7.7–9.5). A total of 85% of alumni indicated positive changes in their professional status and described an increasing role in mentorship of colleagues or residents as a result of new skills. Lack of formal leadership training was noted by three respondents. Informal mentorship equipped fellows practicing in regions of Sub Saharan Africa with competencies to rise in their own leadership and mentoring roles related to enhancing glaucoma management. Suggested higher-order learning objectives and a formal curriculum can be included to optimize leadership training catered to the individual fellow experience. Originality/value Leadership is necessary in health care and specifically in the context of low- and middle-income countries to bring about sustainable developments. The SGF contains a unique “Sandwich” design, focusing on the acquisition of medical and leadership skills. This evaluation outlines successes and challenges of this, and similar fellowship programs. Other programs can use a similar model to promote the development of skills in partnership with the fellows’ home country to strengthen health-care leaders.

Necrotizing enterocolitis (NEC) causes significant morbidity and mortality in premature infants; therefore, the identification of therapeutic and preventative strategies against NEC remains a high priority. The ligand-dependent transcription factor aryl hydrocarbon receptor (AhR) is well known to contribute to the regulation of intestinal microbial communities and amelioration of intestinal inflammation. However, the role of AhR signaling in NEC is unclear. Experimental NEC was induced in 4-d-old wild-type mice or mice lacking AhR expression in the intestinal epithelial cells or AhR expression in CD11c+ cells (AhRΔCD11c) by subjecting animals to twice daily hypoxic stress and gavage feeding with formula supplemented with LPS and enteric bacteria. During NEC, compared with wild-type mice treated with vehicle, littermates treated with an AhR proligand, indole-3-carbinol, had reduced expression of Il1b and Marco, a scavenger receptor that mediates dendritic cell activation and the recognition and clearance of bacterial pathogens by macrophages. Furthermore, indole-3-carbinol treatment led to the downregulation of genes involved in cytokine and chemokine, as revealed by pathway enrichment analysis. AhR expression in the intestinal epithelial cells and their cre-negative mouse littermates were similarly susceptible to experimental NEC, whereas AhRΔCD11c mice with NEC exhibited heightened inflammatory responses compared with their cre-negative mouse littermates. In seeking to determine the mechanisms involved in this increased inflammatory response, we identified the Tim-4− monocyte–dependent subset of macrophages as increased in AhRΔCD11c mice compared with their cre-negative littermates. Taken together, these findings demonstrate the potential for AhR ligands as a novel immunotherapeutic approach to the management of this devastating disease.

This article considers the issue of whether Singapore should amend its trust laws to allow for non-charitable purpose trusts (NCPTs) for the specific purpose of holding company shares in perpetuity. The authors argue that such trusts should be allowed for two reasons. First, NCPTs in general should not be regarded as repugnant to the trust concept. Secondly, the practical advantages of allowing non-charitable trusts in a limited fashion outweigh the disadvantages. The article concludes by proposing possible reforms to the Singapore trust legislation.

Objectives Children with celiac disease (CD) follow a lifelong gluten-free diet. This restrictive diet may be associated with nutritional compromise. Our objectives were, therefore, to evaluate the dietary composition (energy, macronutrients and micronutrients, and fiber) in children with CD compared with healthy controls (HC) and relationship between dietary composition and socioeconomic status. Methods This cross-sectional, case-control study recruited children with CD ages 2 to 18 years and HC matched for age, sex, and socioeconomic status. Clinical, sociodemographic, and dietary information were collected. A false discovery rate correction was applied to the P-value for multiple comparisons (q-value). Results Sixty-five CD children were matched with 65 HC (mean [SD] age: 10.2 [3.6] vs 10.1 [3.7] years, P = 0.96). Compared with HC, CD children had higher intakes of energy (2413.2 [489.9] vs 2190.8 (593.5) kcal/day, P = 0.02), total fat (818.1 ± 180.9 vs 714.3 ± 212.2 kcal/day, q = 0.018), and subtypes of fat (saturated, polyunsaturated, and monounsaturated). There were no differences in other macronutrients, sugar, micronutrients, or fiber between CD and HC, and no difference in dietary intake among CD between socioeconomic disadvantage versus advantage. Children with CD had lower weight z-scores (-0.06 [1.05] vs 0.47 [0.96], P = 0.003) and body mass index (BMI) z-scores (-0.02 [0.88] vs 0.41 [1.09], P = 0.02) than HC. Conclusions Children with CD had higher calorie and fat intake compared with HC. Despite this, CD children had lower weight and BMI z-scores compared with HC.

This study examined neighborhood-level associations among child opportunity, opportunity inequality, racial composition, and frequency of youth psychiatric emergency responses in the nation’s largest county mental health system. Geo-coded data on mobile crisis response (MCR) services, neighborhood opportunity, and child racial/ethnic population were extracted for youth in Los Angeles County between 2016 and 2019 and examined in descriptive and Poisson regression analyses. Black and Multiracial youth were overrepresented in MCRs relative to their county representation. Larger concentrations of child racial/ethnic-minority populations, lower levels of opportunity, and higher levels of opportunity inequality were each associated with higher frequency of MCRs at the zip code level. In adjusted multivariate analyses, Black youth population density and higher education opportunity inequality predicted higher incidence of MCR response. Findings may reflect actual racial disparities in youth mental health need and/or institutional racial biases embedded within community responses to youth behavior.

Objective High-dose glucocorticoids (GC) remain the primary therapy to induce remission in Juvenile Dermatomyositis (JDM). Studies of the natural history of GC associated weight gain in children are very limited, especially in the JDM population. This study aims to measure BMI changes in a cohort of JDM subjects over 60 months and to examine the changes in body composition by DXA. Methods We included all subjects with JDM who had 5 years of follow-up data and multiple DXA studies. BMI and total body fat (TBF) percentiles were calculated based on the CDC published percentile charts. To study the natural history of weight gain and TBF, we assessed the data at four-time points (T0 = baseline, T1 > 1.5 years, T2 = 1.51–3.49 years, T3 = 3.5–5 years). Results 68 subjects (78% female, 70% white) were included in this retrospective study. Paired T-test showed a significant increase in the mean BMI percentile by 17.5 points (P = 0.004) after the initiation of medical treatment, followed by a gradual decrease over the study period. However, the TBF percentile did not change over the study period. TBF in the last visit (T3) had a strong correlation with the T1 BMI, and T1 TBF percentile (correlation coefficients 0.63, 0.56 P P = 0.002) between the TBF percentile and muscle DAS but not the skin DAS. Conclusions Although the BMI percentile decreased throughout the study, the TBF percentile remained high until the end of the study (60 months). This finding raises the concern that some of the reduction in the BMI percentile could reflect a drop in the lean body mass from muscle wasting rather than actual fat loss.

Necrotizing enterocolitis (NEC) is an intestinal disorder that disproportionately affects premature infants and lacks in effective therapeutics. Mihi and colleagues1 demonstrated that the cytokine interleukin-22 promotes intestinal epithelial regeneration and reduces disease severity in an experimental model of NEC., Necrotizing enterocolitis (NEC) is an intestinal disorder that disproportionately affects premature infants and lacks in effective therapeutics. Mihi and colleagues demonstrated that the cytokine interleukin-22 promotes intestinal epithelial regeneration and reduces disease severity in an experimental model of NEC.

Prescription of a high-energy, high-fat diet is a mainstay of nutrition management in cystic fibrosis (CF). However, families may be relying on energy-dense, nutrient-poor (EDNP) foods rather than nutrient-dense (ND) foods to meet dietary targets. We aimed to evaluate the relative contribution of EDNP and ND foods to the usual diets of children with CF and identify sociodemographic factors associated with higher EDNP intakes.This is a cross-sectional comparison of children with CF aged 2-18 years and age- and gender-matched controls. Dietary intake was assessed using the Australian Child and Adolescent Eating Survey (ACAES) food frequency questionnaire.Children with CF (n = 80: 37 males; mean age 9.3 years) consumed significantly more EDNP foods than controls (mean age 9.8 years) in terms of both total energy (median [IQR]: 1301 kcal/day (843-1860) vs. 686 kcal/day (480-1032); p 0.0001), and as a proportion of energy intake (median [IQR]: 44% (34-51) vs. 31% (24-43); p 0.0001). Although children with CF met their estimated energy requirements (median [IQR]: 158% (124-187) vs. 112% (90-137); p 0.0001) and their diets were high in fat (median [IQR]: 38% (35-41) vs. 34% (32-36); p 0.0001), this was largely attributable to EDNP foods. High EDNP intakes (≥10 serves/day) were associated with socioeconomic disadvantage (p = 0.01) and rural residential location (p = 0.03).The energy- and fat-dense CF diet is primarily achieved by overconsumption of EDNP foods, rather than ND sources. This dietary pattern may not be optimal for the future health of children with CF, who are now expected to survive well into adulthood.

Converting checkpoint inhibitor (CPI) resistant patients to responsive requires identifying novel suppressive mechanisms. We identified TREM2 + tumor associated macrophages (TAMs) as being correlated with exhausted CD8 + tumor infiltrating lymphocytes (TILs) in both mouse syngeneic tumor models and human solid tumors of multiple histological types. Fc-domain enhanced anti-TREM2 monoclonal antibody (mAb) therapy promoted anti-tumor immunity by elimination and modulation of TAM populations which led to enhanced CD8 + TIL infiltration and effector function. TREM2 + TAMs were most enriched in human ovarian cancer patients, where TREM2 expression corresponded to disease grade accompanied by worse recurrence-free survival. In an aggressive orthotopic ovarian cancer model, anti-TREM2 mAb therapy drove potent anti-tumor immunity. Together, these results highlight TREM2 as a highly attractive target for immunotherapeutic modulation in patients who are refractory to CPI therapy and likely have a TAM-rich tumor microenvironment.

The following article reviews a collection of photography on view at an exhibition named The Story of Light and Shadow: 20th Century Chinese Photography from Huang Jianpeng's Collection at the National Art Museum of China. Though an exhibition on Chinese photography, it included a sizable collection of Tibet-related photographs taken by early Han Chinese photographers during the early 20th century. Through a brief review of existing scholarship on photography of Tibet and a close reading of the works of Zhuang Xueben, one of the earliest Han Chinese photographers who took photos in Tibetan regions, we see how images produced during the early 20th century in Tibet are coded with layered agencies and complex motivations. Preliminarily contextualizing Zhuang Xueben’s photo-taking aspirations, I argue that early photographers of Tibet are embodiments of complex, overlapping and if not yet incongruous motivations – a complication of their own independent perspectives and professional responsibilities under the larger contextual influence from the society and its aspirations.

A 67-year-old woman presented with painful, acute vision loss after 5 days of fever and muscle aches while visiting the Dominican Republic. She had no recent history of ocular surgery, dental work or recent trauma. Anterior chamber aspiration confirmed an initial diagnosis of endogenous endophthalmitis, positive for Streptococcus mitis that progressed to panophthalmitis on return to Canada. Treatment included systemic antibiotics, intravitreal antibiotics and intravitreal dexamethasone. Despite the best medical treatment, the left eye progressed to corneal perforation 5 weeks after presentation. An evisceration with fitted orbital implant was successful in alleviating pain following the surgery. S. mitis is a rare, but possible cause of endogenous endophthalmitis and panophthalmitis. It was important to work with a multidisciplinary and global team to coordinate and offer appropriate treatment measures. Although vision was lost, evisceration of the left eye provided ocular comfort and good cosmetic outcomes for the patient.

SummaryWe resolved a mechanism connecting tumor epigenetic plasticity with non-genetic adaptive resistance to therapy, with MAPK inhibition ofBRAF-mutant melanomas providing the model. These cancer cells undergo multiple, reversible drug-induced cell-state transitions, ultimately yielding a drug-resistant mesenchymal-like phenotype. A kinetic series of transcriptome and epigenome data, collected over two months of drug treatment and release, revealed changing levels of thousands of genes and extensive chromatin remodeling. However, a 3-step computational algorithm greatly simplified the interpretation of these changes, and revealed that the whole adaptive process was controlled by a gene module activated within just three days of treatment, with RelA driving chromatin remodeling to establish an epigenetic program encoding long-term phenotype changes. These findings were confirmed across several patient-derived cell lines and in melanoma patients under MAPK inhibitor treatment. Co-targeting BRAF and histone-modifying enzymes arrests adaptive transitions towards drug tolerance in epigenetically plastic melanoma cells and may be exploited therapeutically.

Phenotypic plasticity is associated with non-genetic drug tolerance in several cancers. Such plasticity can arise from chromatin remodeling, transcriptomic reprogramming, and/or protein signaling rewiring, and is characterized as a cell state transition in response to molecular or physical perturbations. This, in turn, can confound interpretations of drug responses and resistance development. Using BRAF-mutant melanoma cell lines as the prototype, we report on a joint theoretical and experimental investigation of the cell-state transition dynamics associated with BRAF inhibitor drug tolerance. Thermodynamically motivated surprisal analysis of transcriptome data was used to treat the cell population as an entropy maximizing system under the influence of time-dependent constraints. This permits the extraction of an epigenetic potential landscape for drug-induced phenotypic evolution. Single-cell flow cytometry data of the same system were modeled with a modified Fokker-Planck-type kinetic model. The two approaches yield a consistent picture that accounts for the phenotypic heterogeneity observed over the course of drug tolerance development. The results reveal that, in certain plastic cancers, the population heterogeneity and evolution of cell phenotypes may be understood by accounting for the competing interactions of the epigenetic potential landscape and state-dependent cell proliferation. Accounting for such competition permits accurate, experimentally verifiable predictions that can potentially guide the design of effective treatment strategies., Author summary Cancer cells exhibit varied degrees of phenotypic heterogeneity. These phenotypes, each of them with unique molecular and functional profiles, display dynamic interconversion in response to drug perturbations, and can evolve to form new drug-tolerant phenotypes. Such phenotypic plasticity, in turn, renders tumor cells extremely difficult to treat. To get a quantitative biophysical understanding of the origins of the phenotypic equilibrium and evolution associated with drug tolerance development in highly plastic patient-derived melanoma cells, we employed joint experimental and computational approaches, using either bulk or single cell measurements as input, to interrogate the epigenetic landscape of the phenotypic evolution. We found that the observed phenotypic equilibria were established via competition between state-dependent net proliferation rates and landscape potential. The results reveal how the tumor cells maintain a phenotypic heterogeneity that facilitates appropriate responses to external cues. They implicate that, in certain phenotypically plastic tumor cells, drug targeting the driver oncogenes may not have sustained efficacy unless the phenotypic plasticity of the tumor is co-targeted.

Children with CF have been reported to consume significantly more energy-dense, nutrient-poor foods than controls where there are now concerns of inadequate micronutrient intake. There are no current or comprehensive dietary studies assessing micronutrient intake in CF children.To evaluate micronutrient intake in children with CF compared to recommended dietary intakes (RDIs).Dietary intake of 13 micronutrients was measured in CF children aged 2-18 years and age- and sex-matched controls using a validated food frequency questionnaire (The Australian Child and Adolescent Eating Survey).CF children (n = 82) consumed significantly more energy than controls (n = 82) [3142(2531-3822) kcal vs 2216(1660-2941) kcal; p .001]. Absolute intake in CF children was significantly higher in all micronutrients except vitamin C and folate, however energy-adjusted intake was significantly lower for all micronutrients except vitamin A, sodium, calcium and phosphorous. Energy-adjusted intake in primary school CF children was significantly less than controls in 8/13 micronutrients. Overall, median intakes exceeded the RDIs for all micronutrients however CF children fell short of the RDIs for folate (26.8%), iron (15.9%) and calcium (9.8%). In pre-school, 50% of CF children and 91.7% of controls did not meet the iron RDI. High school CF and control children failed to meet RDIs for 7/13 and 9/13 micronutrients respectively.Increased intake of most micronutrients in CF children was largely attributed to higher energy consumption. However, micronutrient density of the diet declined with increasing age, where high school children failed to meet RDIs for most key micronutrients.

Natural history and behavioral information for species of the genus Pristimantis is scarce. We conducted an extensive study of Pristimantis eremitus, a vulnerable species for which there is scant biological information. We monitored 17 individuals for movements and intraspecific interactions for 13 mo. We describe the species’ variation in dorsal color and pattern, which we used to uniquely identify individuals during the study. We also present results on the habitat utilization and home range of this species, providing evidence that this species shows a preference toward the bromeliad microhabitat when compared with other microhabitat types. We also describe the advertisement call and associated behaviors of the species. We update the known distribution of the species. Our data provide a baseline for future researchers to survey and identify individuals of P. eremitus, and which could be applied comparatively to other species where little of their natural history is known. We also show how an in...

Human small intestinal enteroids are derived from the crypts and when grown in a stem cell niche contain all of the epithelial cell types. The ability to establish human enteroid ex vivo culture systems are important to model intestinal pathophysiology and to study the particular cellular responses involved. In recent years, enteroids from mice and humans are being cultured, passaged, and banked away for future use in several laboratories across the world. This enteroid platform can be used to test the effects of various treatments and drugs and what effects are exerted on different cell types in the intestine. Here, a protocol for establishing primary stem cell-derived small intestinal enteroids derived from neonatal mice and premature human intestine is provided. Moreover, this enteroid culture system was utilized to test the effects of species-specific breast milk. Mouse breast milk can be obtained efficiently using a modified human breast pump and expressed mouse milk can then be used for further research experiments. We now demonstrate the effects of expressed mouse, human, and donor breast milk on the growth and proliferation of enteroids derived from neonatal mice or premature human small intestine.

Objectives The mouse renal cell carcinoma line, Renca, is insensitive to transforming growth factor-beta (TGF-β) in vitro. The present study was conducted to determine whether removal of TGF-β from these tumor cells would inhibit tumor progression in vivo. Methods TGF-β elimination was accomplished either by administration of neutralizing TGF-β antibody into mice receiving intravenous injection of Renca tumor cells or infection of TGF-β antisense expression vector into these tumor cells before subcutaneous injection into recipient mice. Results Although a low dose of TGF-β antibody (5 mg/kg every 3 days) was without any effect, a high dose of TGF-β antibody (50 mg/kg every 3 days), administered to recipient mice, resulted in a significant reduction in lung metastasis and was accompanied by increased apoptosis in the tumor cells. When the tumor cells were transfected with a TGF-β1 antisense expressing vector, a significant reduction occurred in the tumor incidence, as well as the tumor burden. However, in nude mice, cells with reduced TGF-β1 production grew almost as well as did the unmodified Renca cells, suggesting that the host's immune system might play an antitumor role. Conclusions These results indicate that progression of Renca tumor can be inhibited by eliminating TGF-β from the tumor cells. Our results also suggest that, although insensitive to TGF-β under in vitro conditions, Renca tumors could be inhibited by TGF-β removal through the systemic host environment.

The peripheral induction of T regulatory cells can be accomplished by TGF-β through an epigenetic regulation leading to the expression of Foxp3. However, the exact mechanism of such a TGF-β-mediated action remains unclear. In the current study, we found that TGF-β treatment of CD4+CD25− T cells during T cell activation led to a transient inhibition of the phosphorylation of ERK followed by the induction of Foxp3 expression in these cells. Direct treatment with a specific ERK inhibitor, UO126, during CD4+CD25− T cell activation also induced Foxp3 expression and conferred a suppressive function to the induced Foxp3+ T cells. Furthermore, treatment of T cells with either TGF-β or UO126 significantly down-regulated the expression of DNMTs, a reaction normally elicited by demethylation agents, such as 5-Aza-2′-deoxycytidine. These results indicate that the epigenetic regulation of TGF-β-induced expression of Foxp3 may be mediated through the inactivation of ERK.

Transforming growth factor-β (TGF-β) is a potent suppressor of the immune system. In the present study, we investigated the effect of TGF-β resistance on a murine macrophage cell line, RAW 264.7, by overexpressing a dominant negative TGF-β receptor type II (TβRIIDN) construct. As expected, TβRIIDN-expressing RAW cells, designated as RAW-TβRIIDN, were resistant to TGF-β signaling. When these cells were cocultured with the murine renal cell carcinoma cell line, Renca, a dramatic increase in apoptosis of Renca cells was observed. Simultaneously, elevated levels of inducible nitric oxide synthase (iNOS) and tumor necrosis factor-α (TNF-α) in association with IFN-γ were detected in RAW-TβRIIDN cells. When the effects of TNF-α and iNOS were neutralized through the use of neutralizing antibody and NG-methyl-l-arginine, respectively, the enhanced cytotoxicity of TβRIIDN-RAW cells was partially reversed. Taken together, these results show that TGF-β–resistant RAW 264.7 murine macrophage cells have increased cytotoxic activity that is in part mediated by iNOS and TNF-α. [Cancer Res 2007;67(14):6717–24]

CD4+CD25+ T regulatory (Treg) cells were initially described for their ability to suppress autoimmune diseases in animal models. An emerging interest is the potential role of Treg cells in cancer development and progression because they have been shown to suppress antitumor immunity. In this study, CD4+CD25− T cells cultured in conditioned medium (CM) derived from tumor cells, RENCA or TRAMP-C2, possess similar characteristics as those of naturally occurring Treg cells, including expression of Foxp3, a crucial transcription factor of Treg cells, production of low levels of IL-2, high levels of IL-10 and TGF-β, and the ability to suppress CD4+CD25− T cell proliferation. Further investigation revealed a critical role of tumor-derived TGF-β in converting CD4+CD25− T cells into Treg cells because a neutralizing Ab against TGF-β, 1D11, completely abrogated the induction of Treg cells. CM from a nontumorigenic cell line, NRP-152, or irradiated tumor cells did not convert CD4+CD25− T cells to Treg cells because they produce low levels of TGF-β in CM. Finally, we observed a reduced tumor burden in animals receiving 1D11. The reduction in tumor burden correlated with a decrease in tumor-derived TGF-β. Treatment of 1D11 also reduced the conversion of CD4+ T cells into Treg cells and subsequent Treg cell-mediated suppression of antitumor immunity. In summary, we have demonstrated that tumor cells directly convert CD4+CD25− T cells to Treg cells through production of high levels of TGF-β, suggesting a possible mechanism through which tumor cells evade the immune system.

BACKGROUND Inflammation and infection have been linked to the pathogenesis of many cancers including prostate cancer. Components of bacteria and viruses have been identified within pathological specimens of men with prostate cancer. METHODS We characterized the in vitro response of benign prostate epithelial cells to components of infectious agents as they relate to toll-like receptors. RESULTS Primary and immortalized prostate epithelial cells (RWPE) exhibited increased proliferation in response to exposure to lipopolysaccharide (LPS) and CpG DNA. These molecules are well-characterized surrogates for gram negative bacteria (e.g., E. coli) and DNA viruses (e.g., HPV and HSV), which are common in the genitourinary system. Our experiments show that RWPE cells express both TLR 4 (LPS-specific) and TLR 9 (CpG-specific). Targeted knock down of individual TLR expression using siRNA abrogated the proliferative response of RWPE cells to LPS and CpG, respectively. In addition, compared to non-stimulated cells, LPS and CpG up-regulate active NF-kB expression. Increased NF-kB activation was confirmed using RWPE cells that were stably transfected with a NF-kB reporter construct. Interestingly, NF-kB activation was both concentration- and time-dependent when stimulated with LPS. RWPE cells were less susceptible to TNF-alpha induced apoptosis as measured by TUNEL staining when stimulated with CpG or LPS. High concentrations of LPS also prevented cell death as measured by LDH release. CONCLUSIONS Our study has identified a unique mechanism that describes how components of pathogens common in the urinary system may contribute to the malignant transformation of benign prostate epithelia. Prostate 68: 223–229, 2008. © 2007 Wiley-Liss, Inc.

A breakdown in self-tolerance underlies autoimmune destruction of β-cells and type 1 diabetes. A cure by restoring β-cell mass is limited by the availability of transplantable β-cells and the need for chronic immunosuppression. Evidence indicates that inhibiting costimulation through the PD-1/PD-L1 pathway is central to immune tolerance. We therefore tested whether induction of islet neogenesis in the liver, protected by PD-L1–driven tolerance, reverses diabetes in NOD mice. We demonstrated a robust induction of neo-islets in the liver of diabetic NOD mice by gene transfer of Neurogenin3, the islet-defining factor, along with betacellulin, an islet growth factor. These neo-islets expressed all the major pancreatic hormones and transcription factors. However, an enduring restoration of glucose-stimulated insulin secretion and euglycemia occurs only when tolerance is also induced by the targeted overexpression of PD-L1 in the neo-islets, which results in inhibition of proliferation and increased apoptosis of infiltrating CD4+ T cells. Further analysis revealed an inhibition of cytokine production from lymphocytes isolated from the liver but not from the spleen of treated mice, indicating that treatment did not result in generalized immunosuppression. This treatment strategy leads to persistence of functional neo-islets that resist autoimmune destruction and consequently an enduring reversal of diabetes in NOD mice.

The murine renal cell carcinoma (Renca) cells are insensitive to TGF-beta due to a lack of TGF-beta type II receptor (TbetaR-II). The objective of the present study is to determine the mechanism of this loss of sensitivity to TGF-beta in Renca cells. Renca cells were cultured and treated with 5-Aza-2'-Deoxycytidine (5-Aza), a specific inhibitor of methylation. Expression of TGF-beta type I receptor (TbetaRI) and TbetaRII was determined by RT-PCR and Western blot analysis before and after the treatment of Renca cells with 5-Aza. The expression of phosphorylated Smad2 (P-Smad2) was determined by Western blot analysis. TGF-beta levels in the conditioned medium were measured by ELISA. Renca cells did not express TbetaR-II prior to 5-Aza treatment. After 5-Aza treatment, these cells expressed TbetaR-II at both mRNA and protein levels, which corresponded to the restoration of sensitivity to TGF-beta by an increase in P-Smad2. Levels of TGF-beta1 were similar before and after 5-Aza treatment. Results of the present study indicated that, in Renca cells, the loss of sensitivity to TGF-beta is likely due to a promoter hypermethylation in the TbetaR-II gene.

Objective: To test the hypothesis that children and adults with a history of Kawasaki disease (KD) are more likely to have abnormal lipoprotein particle profiles that could place them at increased risk for developing atherosclerosis later in life. Study design: Fasting serum samples were obtained from 192 children and 63 adults with history of KD and 90 age-similar healthy controls. Lipoprotein particle concentrations and sizes were measured by nuclear magnetic resonance spectroscopy (LipoScience Inc, Raleigh, North Carolina), and serum was assayed for total cholesterol (TC), triglycerides, and high-density lipoprotein (HDL) cholesterol (HDL-C). Low-density lipoprotein (LDL) cholesterol was estimated using the Friedewald formula. Data were analyzed in a least-square means model, with adjustment for age and sex and with the use of Holm correction for multiple comparisons. Results: Compared with respective control groups, both adult and pediatric subjects with KD had significantly lower mean very low-density lipoprotein-chylomicron particles, intermediate-density lipoproteins, triglycerides, and TC concentrations. Pediatric subjects with KD had significantly lower LDL particle and LDL cholesterol concentrations and lower mean TC/HDL-C ratio (P

The circadian clock has been shown to regulate metabolic homeostasis. Mice with a deletion of Bmal1, a key component of the core molecular clock, develop hyperglycemia and hypoinsulinemia suggesting β-cell dysfunction. However, the underlying mechanisms are not fully known. In this study, we investigated the mechanisms underlying the regulation of β-cell function by Bmal1. We studied β-cell function in global Bmal1-/- mice, in vivo and in isolated islets ex vivo, as well as in rat insulinoma cell lines with shRNA-mediated Bmal1 knockdown. Global Bmal1-/- mice develop diabetes secondary to a significant impairment in glucose-stimulated insulin secretion (GSIS). There is a blunting of GSIS in both isolated Bmal1-/- islets and in Bmal1 knockdown cells, as compared with controls, suggesting that this is secondary to a loss of cell-autonomous effect of Bmal1. In contrast to previous studies, in these Bmal1-/- mice on a C57Bl/6 background, the loss of stimulated insulin secretion, interestingly, is with glucose but not to other depolarizing secretagogues, suggesting that events downstream of membrane depolarization are largely normal in Bmal1-/- islets. This defect in GSIS occurs as a result of increased mitochondrial uncoupling with consequent impairment of glucose-induced mitochondrial potential generation and ATP synthesis, due to an upregulation of Ucp2. Inhibition of Ucp2 in isolated islets leads to a rescue of the glucose-induced ATP production and insulin secretion in Bmal1-/- islets. Thus, Bmal1 regulates mitochondrial energy metabolism to maintain normal GSIS and its disruption leads to diabetes due to a loss of GSIS.

The aim of this study was to identify differential responses to low concentrations of 17β-estradiol (E2) in primary stromal cell cultures derived from either normal organ donors or benign prostatic hyperplasia or hypertrophy (BPH) specimens. Furthermore, we sought to identify the potential mechanism of E2 action in these cell types, through either a genomic or nongenomic mechanism. We initially treated stromal cells derived from five normal prostates or five BPH specimens with low concentrations of E2 (0.001–1.0 nm) and analyzed their growth response. To determine whether genomic or nongenomic pathways were involved, we performed studies using specific estrogen receptor antagonists to confirm transcriptional activity or MAPK inhibitors to confirm the involvement of rapid signaling. Results of these studies revealed a fundamental difference in the mechanism of the response to E2. In normal cells, we found that a nongenomic, rapid E2 signaling pathway is predominantly involved, mediated by G protein-coupled receptor-30 and the subsequent activation of ERK1/2. In BPH-derived prostate stromal cells, a genomic pathway is predominantly involved because the addition of ICI 182780 was sufficient to abrogate any estrogenic effects. In conclusion, prostate stromal cells respond to far lower concentrations of E2 than previously recognized or examined, and this response is mediated through two distinct mechanisms, depending on its origin. This may provide the basis for new insights into the causes of, and possible treatments for, BPH.

Tumor immunology is characterized by an insufficient immunosurveillance, as most tumors are able to evade host’s immune surveillance program. One of the most profound tumor-derived immune suppressive factors has been TGF-β. Based on this understanding, we have tested adoptive transfer of Indeed, our experimental findings have confirmed this impression. These findings have allowed us to introduce the concept of an antitumor immune response cycle. The postulated cycle consists of three major participants, which are the transferred cytotoxic T-cells, the autologous tumor cells, and the host’s own immune system. The present chapter provides the necessary background, the experimental findings, and the clinical implications of the proposed antitumor immune response cycle. Based on this postulated cycle, we will be able to devise a successful antitumor strategy for advanced cancers.

In this chapter, we introduce a novel concept for an effective treatment of advanced prostate cancer, using our understanding of transforming growth factor (TGF)-β signaling. TGF-β plays an important role in prostate cancer development and progression. Two characteristic features of TGF-β signaling in aggressive prostate cancer are a reduced sensitivity to TGF-β and an overproduction of TGF-β. A reduced sensitivity to TGF-β removes the inhibitory effect of TGF-β and provides a growth advantage for the cancer cells. An overproduction of TGF-β endows cancer cells the ability to metastasize, to enhance angiogenesis, and to evade host’s immune surveillance program, leading to tumor progression and metastasis. TGF-β is a potent tumor-induced immunosuppression. A therapeutic strategy rending host immune cells insensitive to TGF-β should offer an effective approach to eradicate advanced prostate cancer.

In the article listed above, there was an omission in the Funding section. The work was also supported by American Diabetes Association grant 1-14-MN-01 (to L.C.). The online version reflects this change.

Transforming growth factor (TGF)-β is a potent immunosuppressant. Overproduction of TGF-β by tumor cells may lead to tumor evasion from the host immune surveillance and tumor progression. The present study was conducted to develop a treatment strategy through adoptive transfer of tumor-reactive TGF-β-insensitive CD8+ T cells. The mouse TRAMP-C2 prostate cancer cells produced large amounts of TGF-β1 and were used as an experimental model. C57BL/6 mice were primed with irradiated TRAMP-C2 cells. CD8+ T cells were isolated from the spleen of primed animals, were expanded ex vivo, and were rendered TGF-β insensitive by infecting with a retrovirus containing dominant-negative TGF-β type II receptor. Results of in vitro cytotoxic assay revealed that these CD8+ T cells showed a specific and robust tumor-killing activity against TRAMP-C2 cells but were ineffective against an irrelevant tumor line, B16-F10. To determine the in vivo antitumor activity, recipient mice were challenged with a single injection of TRAMP-C2 cells for a period up to 21 days before adoptive transfer of CD8+ T cells was done. Pulmonary metastasis was either eliminated or significantly reduced in the group receiving adoptive transfer of tumor-reactive TGF-β-insensitive CD8+ T cells. Results of immunofluorescent studies showed that only tumor-reactive TGF-β-insensitive CD8+ T cells were able to infiltrate into the tumor and mediate apoptosis in tumor cells. Furthermore, transferred tumor-reactive TGF-β-insensitive CD8+ T cells were able to persist in tumor-bearing hosts but declined in tumor-free animals. These results suggest that adoptive transfer of tumor-reactive TGF-β-insensitive CD8+ T cells may warrant consideration for cancer therapy.

Insulin deficiency in type 1 diabetes leads to disruptions in glucose, lipid, and ketone metabolism with resultant hyperglycemia, hyperlipidemia, and ketonemia. Exogenous insulin and hepatic insulin gene therapy cannot mimic the robust glucose-stimulated insulin secretion (GSIS) from native pancreatic islets. Gene therapy of streptozotocin-diabetic mice with neurogenin 3 (Ngn3) and betacellulin (Btc) leads to the induction of periportal oval cell-derived neo-islets that exhibit GSIS. We hence hypothesized that this gene therapy regimen may lead to a complete correction of the glucose and lipid metabolic abnormalities associated with insulin deficiency; we further hypothesized that the neo-islets formed in response to Ngn3-Btc gene delivery may display an ultrastructure and transcription profile similar to that of pancreatic islets. We injected streptozotocin-diabetic mice with helper-dependent adenoviral vectors carrying Ngn3 and Btc, which restored GSIS and reversed hyperglycemia in these animals. The treatment also normalized hepatic glucose secretion and reversed ketonemia. Furthermore, it restored hepatic glycogen content and reinstated hepatic lipogenesis-related gene transcripts back to nondiabetic levels. By transmission electron microscopy, the neo-islets displayed electron-dense granules that were similar in appearance to those in pancreatic islets. Finally, using RNA obtained by laser capture microdissection of the periportal neo-islets and normal pancreatic islets, we found that the neo-islets and pancreatic islets exhibited a very similar transcription profile on microarray-based transcriptome analysis. Taken together, this indicates that Ngn3-Btc gene therapy corrects the underlying dysregulated glucose and lipid metabolism in insulin-deficient diabetic mice by inducing neo-islets in the liver that are similar to pancreatic islets in structure and gene expression profile.

Summary The transcription factor Neurogenin3 (Ngn3) is required for islet-cell type specification. Here, we show that hepatic gene transfer of Ngn3 transiently induces insulin in terminally differentiated hepatocytes but fails to transdifferentiate them, i.e., switch their lineage into islet cells. However, Ngn3 leads to long-term diabetes reversal in mice due to the emergence of periportal islet-like cell clusters. These neo-islets display glycemia-regulated insulin, β-cell-specific transcripts, and an islet-specific transcription cascade, and they produce all four major islet hormones. They appear to arise from hepatic progenitor cells, most likely endoderm-derived oval cells. Thus, transfer of a single lineage-defining transcription factor, Ngn3, is sufficient to induce cell-lineage switching from a hepatic to an islet lineage in these progenitor cells, a process consistent with transdetermination, i.e, lineage switching in lineage-determined, but not terminally differentiated, cells. This paradigm of induced transdetermination of receptive progenitor cells in vivo may be generally applicable to therapeutic organogenesis for multiple diseases, including diabetes.