Dextrin conjugation to colistin inhibits its toxicity, cellular uptake and acute kidney injury in vivo

The acute kidney injury (AKI) and dose-limiting nephrotoxicity, which occurs in 20-60% of patients following systemic administration of colistin, represents a challenge in the effective treatment of multi-drug resistant Gram-negative infections. To reduce clinical toxicity of colistin and improve targeting to infected/inflamed tissues, we previously developed dextrin-colistin conjugates, whereby colistin is designed to be released by amylase-triggered degradation of dextrin in infected and inflamed tissues, after passive targeting by the enhanced permeability and retention effect. Whilst it was evident in vitro that polymer conjugation can reduce toxicity and prolong plasma half-life, without significant reduction in antimicrobial activity of colistin, it was unclear how dextrin conjugation would alter cellular uptake and localisation of colistin in renal tubular cells in vivo. We discovered that dextrin conjugation effectively reduced colistin's toxicity towards human kidney proximal tubular epithelial cells (HK-2) in vitro, which was mirrored by significantly less cellular uptake of Oregon Green (OG)-labelled dextrin-colistin conjugate, when compared to colistin. Using live-cell confocal imaging, we revealed localisation of both, free and dextrin-bound colistin in endolysosome compartments of HK-2 and NRK-52E cells. Using a murine AKI model, we demonstrated dextrin-colistin conjugation dramatically diminishes both proximal tubular injury and renal accumulation of colistin. These findings reveal new insight into the mechanism by which dextrin conjugation can overcome colistin's renal toxicity and show the potential of polymer conjugation to improve the side effect profile of nephrotoxic drugs.

Tissue-specific transcriptional programming of macrophages controls the microRNA transcriptome targeting multiple functional pathways

Recent interest in the biology and function of peritoneal tissue resident macrophages (pMΦ) has led to a better understanding of their cellular origin, programming, and renewal. The programming of pMΦ is dependent on microenvironmental cues and tissue-specific transcription factors, including GATA6. However, the contribution of microRNAs remains poorly defined. We conducted a detailed analysis of the impact of GATA6 deficiency on microRNA expression in mouse pMΦ. Our data suggest that for many of the pMΦ, microRNA composition may be established during tissue specialization and that the effect of GATA6 knockout is largely unable to be rescued in the adult by exogenous GATA6. The data are consistent with GATA6 modulating the expression pattern of specific microRNAs, directly or indirectly, and including miR-146a, miR-223, and miR-203 established by the lineage-determining transcription factor PU.1, to achieve a differentiated pMΦ phenotype. Lastly, we showed a significant dysregulation of miR-708 in pMΦ in the absence of GATA6 during homeostasis and in response to LPS/IFN-γ stimulation. Overexpression of miR-708 in mouse pMΦ in vivo altered 167 mRNA species demonstrating functional downregulation of predicted targets, including cell immune responses and cell cycle regulation. In conclusion, we demonstrate dependence of the microRNA transcriptome on tissue-specific programming of tissue macrophages as exemplified by the role of GATA6 in pMΦ specialization.

Lentiviral Vector Preparation for Efficient Gene and MicroRNA Modulation of Peritoneal Cavity Tissue-Resident Macrophages In Vivo in Mice

Peritoneal tissue-resident macrophages have broad functions in the maintenance of homeostasis and are involved in pathologies within local and neighboring tissues. Their functions are dictated by microenvironmental cues; thus, it is essential to investigate their behavior in an in vivo physiological niche. Currently, specific peritoneal macrophage-targeting methodologies employ whole-mouse transgenic models. Here, a protocol for effective in vivo modulation of mRNA and small RNA species (e.g., microRNA) expression in peritoneal macrophages using lentivirus particles is described. Lentivirus preparations were made in HEK293T cells and purified on a single sucrose layer. In vivo validation of lentivirus effectivity following intraperitoneal injection revealed predominant infection of macrophages restricted to local tissue. Targeting of peritoneal macrophages was successful during homeostasis and thioglycolate-induced peritonitis. The limitations of the protocol, including low-level inflammation induced by intraperitoneal delivery of lentivirus and time restrictions for potential experiments, are discussed. Overall, this study presents a quick and accessible protocol for the rapid assessment of gene function in peritoneal macrophages in vivo.

Th1 Cells Alter the Inflammatory Signature of IL-6 by Channeling STAT Transcription Factors to Alu-like Retroelements

Cytokines that signal via STAT1 and STAT3 transcription factors instruct decisions affecting tissue homeostasis, antimicrobial host defense, and inflammation-induced tissue injury. To understand the coordination of these activities, we applied RNA sequencing, chromatin immunoprecipitation sequencing, and assay for transposase-accessible chromatin with high-throughput sequencing to identify the transcriptional output of STAT1 and STAT3 in peritoneal tissues from mice during acute resolving inflammation and inflammation primed to drive fibrosis. Bioinformatics focused on the transcriptional signature of the immunomodulatory cytokine IL-6 in both settings and examined how profibrotic IFN-γ-secreting CD4+ T cells altered the interpretation of STAT1 and STAT3 cytokine cues. In resolving inflammation, STAT1 and STAT3 cooperated to drive stromal gene expression affecting antimicrobial immunity and tissue homeostasis. The introduction of IFN-γ-secreting CD4+ T cells altered this transcriptional program and channeled STAT1 and STAT3 to a previously latent IFN-γ activation site motif in Alu-like elements. STAT1 and STAT3 binding to this conserved sequence revealed evidence of reciprocal cross-regulation and gene signatures relevant to pathophysiology. Thus, we propose that effector T cells retune the transcriptional output of IL-6 by shaping a regulatory interplay between STAT1 and STAT3 in inflammation.

Associations between serum glucose, insulin, insulin resistance and the risk of incident primary liver cancer or chronic liver disease mortality: a nested case-control study

BACKGROUND

To evaluate the associations between pre-diagnostic levels of serum insulin, glucose and insulin resistance (HOMA-IR) and future risk of incident primary liver cancer (PLC) or chronic liver disease (CLD)-related mortality.

METHODS

We used a nested case-control design to evaluate subjects over 22 years of follow-up. Glucose, insulin, and three markers of hepatitis B virus (HBV) and hepatitis C virus were measured in fasting baseline serum from 119 incident PLCs, 157 CLD-death cases and 512 matched controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression to estimate the associations between insulin, glucose, HOMA-IR and the risk of PLC or CLD death.

RESULTS

Compared with the lowest quartile of insulin, multivariable adjusted models showed that subjects in the highest quartile had elevated odds of developing PLC (OR_Q4/Q1 = 2.42, 95% CI = 1.26-4.75, P_trend = 0.007), particularly in HBV-positive subjects (P_interaction = 0.040), and of CLD death (OR_Q4/Q1 = 1.80, 95% CI = 1.02-3.21, P_trend = 0.018). For glucose, in the HBV-positive group, subjects in the fourth quartile had an increased risk of PLC (OR_Q4/Q1 = 2.18, 95% CI = 1.07-4.60, P_trend = 0.009), and of CLD mortality (OR_Q4/Q1 = 1.75, 95% CI = 0.95-3.28, P_trend = 0.019). Subjects with the highest HOMA-IR values had a threefold risk of developing PLC (OR_Q4/Q1 = 2.94, 95% CI = 1.54-5.87, P_trend = 0.001), and a twofold risk of CLD death (OR_Q4/Q1 = 2.20, 95% CI = 1.25-3.94, P_trend = 0.005).

CONCLUSIONS

We found that serum insulin and HOMA-IR could potentially be risk factors for PLC or CLD death.

An international report on bacterial communities in esophageal squamous cell carcinoma

The incidence of esophageal squamous cell carcinoma (ESCC) is disproportionately high in the eastern corridor of Africa and parts of Asia. Emerging research has identified a potential association between poor oral health and ESCC. One possible link between poor oral health and ESCC involves the alteration of the microbiome. We performed an integrated analysis of four independent sequencing efforts of ESCC tumors from patients from high- and low-incidence regions of the world. Using whole genome sequencing (WGS) and RNA sequencing (RNAseq) of ESCC tumors from 61 patients in Tanzania, we identified a community of bacteria, including members of the genera Fusobacterium, Selenomonas, Prevotella, Streptococcus, Porphyromonas, Veillonella and Campylobacter, present at high abundance in ESCC tumors. We then characterized the microbiome of 238 ESCC tumor specimens collected in two additional independent sequencing efforts consisting of patients from other high-ESCC incidence regions (Tanzania, Malawi, Kenya, Iran, China). This analysis revealed similar ESCC-associated bacterial communities in these cancers. Because these genera are traditionally considered members of the oral microbiota, we next explored whether there was a relationship between the synchronous saliva and tumor microbiomes of ESCC patients in Tanzania. Comparative analyses revealed that paired saliva and tumor microbiomes were significantly similar with a specific enrichment of Fusobacterium and Prevotella in the tumor microbiome. Together, these data indicate that cancer-associated oral bacteria are associated with ESCC tumors at the time of diagnosis and support a model in which oral bacteria are present in high abundance in both saliva and tumors of some ESCC patients.

CSMD1 Shows Complex Patterns of Somatic Copy Number Alterations and Expressions of mRNAs and Target Micro RNAs in Esophageal Squamous Cell Carcinoma

Simple Summary

Human Cub and Sushi Multiple Domains 1 (CSMD1) is a novel candidate tumor-suppressor gene. We investigated CSMD1 in esophageal squamous cell carcinoma (ESCC) by performing an integrated analysis of somatic DNA alterations (i.e., copy number alteration, allelic imbalance, and loss of heterozygosity) with RNA expressions (mRNA and target miRNAs) on specimens from the same ESCC patients, using data from SNP, miRNA, and RT-PCR arrays. Our results indicate that the CSMD1 gene may play a role in the development of ESCC through complex patterns involving somatic alterations and mRNA expression. Furthermore, somatic copy number alterations in SNPs located in non-coding regions of CSMD1 appear to influence expression of both this gene and its target miRNAs.

Abstract

Background: Human Cub and Sushi Multiple Domains 1 (CSMD1) is a novel candidate tumor-suppressor gene that codes for multiple domains, including complement regulatory and adhesion proteins, and has recently been shown to have alterations in multiple cancers. We investigated CSMD1 in esophageal squamous cell carcinoma (ESCC) by performing an integrated analysis on somatic copy number alterations (CNAs), including copy-number gain or loss, allelic imbalance (AI), loss of heterozygosity (LOH), and the expressions of mRNA and its target miRNAs on specimens from the same patients with ESCC. Results: (i) Two-thirds of ESCC patients had all three types of alterations studied—somatic DNA alterations in 70%, and abnormal expressions of CSMD1 RNA in 69% and in target miRNAs in 66%; patterns among these alterations were complex. (ii) In total, 97% of 888 CSMD1 SNPs studied showed somatic DNA alterations, with most located near exons 4–11, 24–25, 39–40, 55–56, and 69–70. (iii) In total, 68% of SNPs with a CNA were correlated with expression of CSMD1. (iv) A total of 33 correlations between non-coding SNPs and expression of CSMD1 target miRs were found. Conclusions: Our results indicate that the CSMD1 gene may play a role in ESCC through complex patterns of DNA alterations and RNA and miRNA expressions. Alterations in some somatic SNPs in non-coding regions of CSMD1 appear to influence expression of this gene and its target miRNAs.

The Association Between Family History of Upper Gastrointestinal Cancer and the Risk of Death from Upper Gastrointestinal Cancer-based on Linxian Dysplasia Nutrition Intervention Trial (NIT) Cohort

Objective

Explore the influence of family history of upper gastrointestinal (UGI) cancer on UGI cancer death, based on the Linxian Dysplasia Nutrition Intervention Trial (NIT) cohort.

Methods

Family history of UGI cancer was defined as at least one first-degree relative (parent, child, or sibling) had a history of esophageal or gastric cancer. Cancer death was carried out by ICD-10 code. Family history information was collected at baseline and cancer deaths were assessed at each annual follow-up. The COX proportional risk model was used to estimate the hazard ratio (HR) and 95% confidence interval (95% CI). We compared the positive family history group with the negative to determine the risk of family history on UGI cancer death. The effect of category of relatives, number of relatives with UGI cancer, and diagnosis age of relatives on the UGI death risk were further analyzed. Interaction and stratification analyses were done to see the subgroup effects. Sensitivity analyses were also conducted by exclusion of individuals who were followed up less than three years. We considered controlling of covariates including: gender, age (continuity), community, education level, number of siblings (continuity), BMI (continuity), smoking, alcohol use, fresh fruit intake, fresh vegetable intake, hot beverage intake, edible oil intake, meat intake, and moldy staple food intake. All food intake variables were converted into categorical variables.

Results

From1985 to2015, we followed up total 3,318 individuals with 898 UGI cancer deaths (537 from ESCC, 77 from GNCC, and 284 from GCC). In a single factor analysis, family history of UGI cancer increased the risk of death of esophageal squamous cell carcinoma (ESCC) by 27% (HR=1.270, 95%CI1.072-1.504). No associations were observed in gastric cardia carcinoma (GCC) and gastric non-cardia carcinoma (GNCC). After adjusting for multi-factor, a family history of UGI cancer risk of death increased by 31.9% from ESCC (HR=1.319,95%CI:1.110-1.567). Subgroup analysis of different types of relatives with UGI cancers, UGI cancers in the mother (HR=1.457,95%CI:1.200-1.768), brother (HR=1.522,95%CI:1.117-2.073), and sister (HR=1.999,95%CI:1.419-2.817) were independent risk factors for ESCC death, while the father was not. In addition, 2 relatives with UGI cancer (HR=1.495, 95%, CI:1.110-2.013) and ≥3 relatives with UGI cancer (HR=2.836, 95%CI:1.842-4.367) significantly increased the risk of ESCC death, and the trend test was statistically significant (P<0.001). Relatives’ diagnostic age of 51-60 years (HR=1.322, 95%CI:1.046-1.672) and 41-50 years (HR=1.442, 95%CI:1.078-1.930) were the risk factors for ESCC death, with statistical significance in the trend test (P=0.010). No statistically significant result of the family history effect on the risk of death from GCC or GNCC was found. Sensitivity analysis of 80% of subjects, randomly selected, did not change the results.

Conclusion

A family history of UGI cancer may predict the risk of death from ESCC but not from GCC or GNCC. UGI cancer in the mother may predict the risk of death from ESCC, but not father, which indicates gender differences. Gender and smoking are the interaction items with family history in a similar extent. In the subgroup, the risk of ESCC death is more distinct by family history in younger, female, and better-lifestyle individuals, which indicates the unique role of genetic factors.

Combined risk factors and risk of upper gastrointestinal cancer mortality in the Linxian general population

We aimed to explore the association of combined risk factors with risk of death from upper gastrointestinal (UGI) cancer, including esophageal squamous cell carcinoma (ESCC), gastric cardia carcinoma (GCC) and gastric noncardia carcinoma (GNCC) in the Linxian Nutrition Intervention Trial (NIT) cohort. The NIT cohort included 29 584 healthy adults. A combined risk score (CRS) was calculated using a point system method based on 10 risk factors collected at baseline, including gender, smoking, alcohol drinking, body mass index, family history of UGI cancer, drinking tap water, tooth loss and consumption of fresh fruit, eggs and meat. Possible score ranged from 0 to 31, and higher score indicated as poorer health status. Subjects were divided into three groups by the CRS (<12 points, 12 to 20 points and >20 points). The group of CRS <12 points was considered as the reference. During the 30-year follow-up, we identified 4553 UGI cancer deaths. Compared to subjects with a CRS <12 points, the adjusted HRs for CRS of 12 to 20 points and >20 points were 1.69 (95% CI: 1.56-1.83) and 3.06 (95% CI: 2.82-3.33) for UGI cancer mortality, respectively (P_trend  < .001). Comparable associations were also observed for ESCC, GCC and GNCC mortality. Results remained similar across different age groups (P_interaction  > .05). All HRs observed in the second half follow-up period were stronger than that observed in the first half follow-up period. Our study indicated that higher CRS was associated with increased risk of UGI cancer mortality. Appropriate measures should be taken to reduce unhealthy lifestyles.

Mortality after multivitamin supplementation: Nearly 35-year follow-up of the randomized Linxian Dysplasia Nutrition Intervention Trial

BACKGROUND

The objective of this study was to update the association between multivitamin supplementation and total or cause-specific mortality in a population with a high prevalence of undernutrition in China.

METHODS

The Linxian Dysplasia Nutrition Intervention Trial was a randomized, double-blind, placebo-controlled trial in which 3318 persons aged 40-69 years with esophageal squamous dysplasia were assigned to receive daily multivitamin supplementation or a placebo for 6 years and were followed for 29 years. The primary outcome was esophageal/gastric cardia cancer mortality. The data were analyzed with Cox proportional hazards regression models. Subgroup analyses were performed by common characteristics such as age and gender.

RESULTS

The cumulative total mortality was 83.5%. Multivitamin supplementation did not affect total or cause-specific mortality in the participants as a whole (hazard ratio [HR], 0.96; 95% confidence interval [CI], 0.89-1.03). Subgroup analyses showed that no association between multivitamin supplementation and all-cause mortality was observed in men (HR, 0.90; 95% CI, 0.81-1.01), women (HR, 1.01; 95% CI, 0.91-1.12), younger participants (HR, 0.97; 95% CI, 0.87-1.08), or older participants (HR, 0.94; 95% CI, 0.85-1.04). Significant reductions in heart disease mortality (HR, 0.64; 95% CI, 0.47-0.87) and cerebrovascular disease mortality (HR, 0.74; 95% CI, 0.56-1.00) were seen in older men. In a subgroup of younger men and a subgroup of moderate or severe dysplasia, subjects receiving multivitamin supplementation had a lower risk of esophageal/cardia cancer mortality (HR for younger men, 0.76; 95% CI, 0.58-0.99; HR for moderate or severe dysplasia, 0.76; 95% CI, 0.58-1.00). No association between multivitamin supplementation and any cause-specific mortality was observed in a mild dysplasia population.

CONCLUSIONS

Multivitamin supplementation in a population with esophageal squamous dysplasia was not associated with the risk of total mortality in the 35-year follow-up of this randomized controlled trial. In light of this and previous trials, multivitamin supplements should be used thoughtfully to improve health status of populations with esophageal squamous dysplasia.

LAY SUMMARY

Multivitamin supplementation is common, yet its effect on mortality is unclear. The aim of this study was to update the long-term effects of multivitamin supplementation on total and cause-specific mortality during nearly 35 years of follow-up in the Linxian Dysplasia Nutrition Intervention Trial in China. Multivitamin supplementation in a population with esophageal squamous dysplasia was not associated with the risk of total mortality in the 35-year follow-up of this randomized controlled trial, and this indicates that multivitamin supplements should be used thoughtfully to improve health status.

Relationships between serum iron and liver diseases in nutrition intervention trials: A nested case-control study

BACKGROUND

Serum iron is associated with the risk of several diseases. However, limited prospective studies have been performed between serum iron and the subsequent risk of chronic liver disease (CLD) and primary liver cancer (PLC) incidence.

METHODS

We performed a nested case-control study using data from the Linxian Nutrition Intervention Trials among participants who developed PLC incidence or died from CLD over 22-years of follow-up. We calculated the odds ratios (ORs) and 95% confidence intervals (CIs) to estimate the risk of PLC incidence or CLD death in different quintile of baseline serum iron using logistic regression.

RESULTS

Individuals with serum iron in the highest quintile, compared to those in the second quintile (the reference), had an increased risk of CLD mortality (OR=2.02, 95% CI=1.27-3.27, P_trend=0.011). The association was stronger among HCV-positive participants (P_interaction=0.005). For PLC incidence, the risk estimates were above one, but not statistically significant (all P > 0.05).

CONCLUSIONS

A significant positive association was found between serum iron and the risk of CLD-related mortality, especially in HCV-positive subjects. Our results suggest that serum iron plays a risk role in CLD death but not in PLC incidence.

Quantitative evaluation of radon, tobacco use and lung cancer association in an occupational cohort with 27 follow-up years

BACKGROUND

Occupational radon cohorts provide important information about exposure at residential level, which are difficult to observe prospectively. However, evidence about radon-related lung cancer risks from initial exposure in childhood or interaction between radon and smoking is still limited.

METHODS

A total of 6017 tin miners with at least 10 years of underground radon exposure were enrolled beginning in 1992 and followed for up to 27 years. Lung cancer risks were estimated by modeling total and intensity of radon exposure.

RESULTS

A total of 933 lung cancer cases occurred in this cohort over 89,092 person-years of follow up. Excess relative risk increased by 0.96% per cumulative working level month (WLM). A unique aspect of this population was the early age at first radon exposure for workers. Results showed that lung cancer risk from initial radon exposure in childhood (<13 years old) was greater than risk when first exposure occurred at later ages (13-17, 18-24, and ≥ 25 years old). Moreover, risk declined with years since last exposure and attained age, but increased with age at last exposure. Importantly, these patterns were stable after adjustment for tobacco use or arsenic exposure. For joint effects of radon and other agents, our results support sub-multiplicative as the most likely model for interaction between radon and tobacco use or arsenic exposure.

CONCLUSION

This study highlights the possible importance of radon exposure in childhood in cancer etiology and suggests another potential strategy to mitigate the global lung cancer burden.

Combined Lifestyle Factors and Risk of All-Cause and Cause-Specific Mortality Among Participants in the Linxian Nutrition Intervention Trial: A Cohort, Observational Study

Background

Several studies have indicated that combinations of lifestyle and dietary factors are associated with risk of total mortality and death from cardiovascular disease and cancer, but limited data are available from long-term follow-up studies in China.

Methods

This study was a observational cohort study. We prospectively examined the associations of combined lifestyle factors and risk of total and cause-specific mortality in the Linxian General Population Nutrition Intervention Trial (NIT) cohort that included 29,584 healthy adults. A points system method was used to calculate a combined risk score of five lifestyle factors, including smoking, alcohol drinking, body mass index, vegetable intake and fruit intake. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs).

Results

Overall, adjusted hazard ratios for mortality increased progressively with an increasing combined risk score. Compared to individuals with a score of zero or one, HRs (95%CIs) for a score of five or above were 1.59 (1.44–1.75) for all-cause mortality, 1.67 (1.48–1.88) for heart disease, 1.69 (1.52–1.88) for stroke, and 1.34 (1.21, 1.47) for cancer. This association for mortality was seen consistently, regardless of gender and age at baseline.

Conclusions

A higher combined risk score was positively associated with risk of total, heart disease, stroke, and cancer mortality. These findings could provide further evidence for the idea that healthy lifestyle is the optimal way to reduce the risk of premature death, and encourage behavior change.

3R Blackboard: A platform for animal and organ sharing

Since the embedding of the principles of the 3Rs (Replacement, Reduction and Refinement) in national and international regulations on the use of animals, scientists have been challenged to find ways to reduce the number of animals in their research. Here, we present a digital platform, called '3R Backboard', linked to a laboratory animal management system, which facilitates sharing of surplus biological materials from animals (e.g. tissues, organs and cells) to other research teams. Based on information provided, such as genotype, age and sex, other animal workers were able to indicate their interest in collecting specific tissues and to communicate with the person providing the animals. A short pilot study of this approach conducted in a limited academic environment presented strong evidence of its effectiveness and resulted in a notable reduction of the number of mice used. In addition, the use of 3R Blackboard led to resource saving, knowledge exchange and even establishment of new collaboration.

Oxylipin metabolism is controlled by mitochondrial β-oxidation during bacterial inflammation

Oxylipins are potent biological mediators requiring strict control, but how they are removed en masse during infection and inflammation is unknown. Here we show that lipopolysaccharide (LPS) dynamically enhances oxylipin removal via mitochondrial β-oxidation. Specifically, genetic or pharmacological targeting of carnitine palmitoyl transferase 1 (CPT1), a mitochondrial importer of fatty acids, reveal that many oxylipins are removed by this protein during inflammation in vitro and in vivo. Using stable isotope-tracing lipidomics, we find secretion-reuptake recycling for 12-HETE and its intermediate metabolites. Meanwhile, oxylipin β-oxidation is uncoupled from oxidative phosphorylation, thus not contributing to energy generation. Testing for genetic control checkpoints, transcriptional interrogation of human neonatal sepsis finds upregulation of many genes involved in mitochondrial removal of long-chain fatty acyls, such as ACSL1,3,4, ACADVL, CPT1B, CPT2 and HADHB. Also, ACSL1/Acsl1 upregulation is consistently observed following the treatment of human/murine macrophages with LPS and IFN-γ. Last, dampening oxylipin levels by β-oxidation is suggested to impact on their regulation of leukocyte functions. In summary, we propose mitochondrial β-oxidation as a regulatory metabolic checkpoint for oxylipins during inflammation.

A Novel Strategy to Identify Haematology Patients at High Risk of Developing Aspergillosis

Invasive Aspergillosis (IA), typically caused by the fungus Aspergillus fumigatus, is a leading cause of morbidity and mortality in immunocompromised patients. IA remains a significant burden in haematology patients, despite improvements in the diagnosis and treatment of Aspergillus infection. Diagnosing IA is challenging, requiring multiple factors to classify patients into possible, probable and proven IA cohorts. Given the low incidence of IA, using negative results as exclusion criteria is optimal. However, frequent false positives and severe IA mortality rates in haematology patients have led to the empirical use of toxic, drug-interactive and often ineffective anti-fungal therapeutics. Improvements in IA diagnosis are needed to reduce unnecessary anti-fungal therapy. Early IA diagnosis is vital for positive patient outcomes; therefore, a pre-emptive approach is required. In this study, we examined the sequence and expression of four C-type Lectin-like receptors (Dectin-1, Dectin-2, Mincle, Mcl) from 42 haematology patients and investigated each patient's anti-Aspergillus immune response (IL-6, TNF). Correlation analysis revealed novel IA disease risk factors which we used to develop a pre-emptive patient stratification protocol to identify haematopoietic stem cell transplant patients at high and low risk of developing IA. This stratification protocol has the potential to enhance the identification of high-risk patients whilst reducing unnecessary treatment, minimizing the development of anti-fungal resistance, and prioritising primary disease treatment for low-risk patients.

Arsenic, tobacco use, and lung cancer: An occupational cohort with 27 follow-up years

BACKGROUND

We explored the shape of the exposure-response relationship of arsenic-related lung cancer and the interaction between arsenic and tobacco use.

METHODS

A total of 3278 tin miners with at least 10 years of arsenic exposure were enrolled since 1992 and followed up for 27 years. After excluding radon-exposed miners and former smokers, 1620 miners were included into the sub-cohort. Lung cancer risks were estimated by modeling total exposure and intensity of arsenic exposure.

RESULTS

The cohort experienced 73,866 person-years and 414 lung cancer cases. Firstly, the ERR/mg/m3-year was 0.0033 (95% CI: 0.0014-0.0045) in arsenic concentration <3 mg/m³ and 0.0056 (95% CI: 0.0035-0.0073) in arsenic concentration ≥3 mg/m³. After adjusting for cumulative arsenic exposure, and the ERR/mg/m³ increased with increasing intensity (0.129 (95% CI: 0.039, 0.189)). Secondly, an unique aspect of this population was the early age at first arsenic exposure for workers. Results showed that lung cancer incidence risk from exposed in childhood (<13 years) was non-significantly greater than those in other age groups (13-17 and ≥ 18 years). Finally, the most likely joint effects of inhaled arsenic and tobacco use was sub-multiplicative.

CONCLUSION

This study enlightened us that for fixed cumulative arsenic exposure, higher concentration over shorter duration might be more deleterious than lower concentration over longer duration. Substantial reductions in the lung cancer burden of smokers exposed to arsenic could be achieved by reductions in either exposure.

Association between serum ferritin, incident primary liver cancer, and chronic liver disease mortality in the Linxian Nutrition Intervention Trials: A nested case-control study

BACKGROUND AND AIM

Previous studies suggest that serum ferritin may be associated with higher risk of liver cancer. However, additional studies of the association are needed. It is also not clear whether serum ferritin is associated with mortality from chronic liver disease (CLD).

METHODS

We performed a nested case-control study in the Linxian Nutrition Intervention Trials. Baseline serum ferritin was measured for 226 incident primary liver cancer cases, 281 CLD mortalities diagnosed, and 1061 age-matched, gender-matched, and trial-matched controls. We used multivariable logistic regression models to calculate odds ratios and 95% confidence intervals. Subgroup analysis and interaction tests were performed by age, gender, alcohol drinking, hepatitis B virus seropositivity (HBV+)/hepatitis C virus seropositivity (HCV+), and trial.

RESULTS

Participants with serum ferritin in the highest quartile, as compared with those in the lowest quartile, had an increased risk of CLD mortality (odds ratio = 1.72, 95% confidence interval = 1.12, 2.64, P-trend < 0.01). Moreover, the association with higher serum ferritin was stronger among alcohol drinkers and those who were HCV+ (P-interaction < 0.05). For incident liver cancer, risk estimates were above one but were not statistically significant.

CONCLUSION

In this study, higher levels of serum ferritin at baseline were associated with subsequent mortality from CLD, particularly if combined with alcohol drinking or viral hepatitis. Further work is warranted to confirm our findings.

A Human Dectin-2 Deficiency Associated With Invasive Aspergillosis

Immunocompromised patients are highly susceptible to invasive aspergillosis. Herein, we identified a homozygous deletion mutation (507 del C) resulting in a frameshift (N170I) and early stop codon in the fungal binding Dectin-2 receptor, in an immunocompromised patient. The mutated form of Dectin-2 was weakly expressed, did not form clusters at/near the cell surface and was functionally defective. Peripheral blood mononuclear cells from this patient were unable to mount a cytokine (tumor necrosis factor, interleukin 6) response to Aspergillus fumigatus, and this first identified Dectin-2–deficient patient died of complications of invasive aspergillosis.

Single-Nucleus RNA Sequencing Identifies New Classes of Proximal Tubular Epithelial Cells in Kidney Fibrosis

BACKGROUND

Proximal tubular cells (PTCs) are the most abundant cell type in the kidney. PTCs are central to normal kidney function and to regeneration versus organ fibrosis following injury. This study used single-nucleus RNA sequencing (snRNAseq) to describe the phenotype of PTCs in renal fibrosis.

METHODS

Kidneys were harvested from naïve mice and from mice with renal fibrosis induced by chronic aristolochic acid administration. Nuclei were isolated using Nuclei EZ Lysis buffer. Libraries were prepared on the 10× platform, and snRNAseq was completed using the Illumina NextSeq 550 System. Genome mapping was carried out with high-performance computing.

RESULTS

A total of 23,885 nuclei were analyzed. PTCs were found in five abundant clusters, mapping to S1, S1-S2, S2, S2-cortical S3, and medullary S3 segments. Additional cell clusters ("new PTC clusters") were at low abundance in normal kidney and in increased number in kidneys undergoing regeneration/fibrosis following injury. These clusters exhibited clear molecular phenotypes, permitting labeling as proliferating, New-PT1, New-PT2, and (present only following injury) New-PT3. Each cluster exhibited a unique gene expression signature, including multiple genes previously associated with renal injury response and fibrosis progression. Comprehensive pathway analyses revealed metabolic reprogramming, enrichment of cellular communication and cell motility, and various immune activations in new PTC clusters. In ligand-receptor analysis, new PTC clusters promoted fibrotic signaling to fibroblasts and inflammatory activation to macrophages.

CONCLUSIONS

These data identify unrecognized PTC phenotype heterogeneity and reveal novel PTCs associated with kidney fibrosis.

PIP2 depletion and altered endocytosis caused by expression of Alzheimer's disease-protective variant PLCγ2 R522

Variants identified in genome-wide association studies have implicated immune pathways in the development of Alzheimer's disease (AD). Here, we investigated the mechanistic basis for protection from AD associated with PLCγ2 R522, a rare coding variant of the PLCG2 gene. We studied the variant's role in macrophages and microglia of newly generated PLCG2-R522-expressing human induced pluripotent cell lines (hiPSC) and knockin mice, which exhibit normal endogenous PLCG2 expression. In all models, cells expressing the R522 mutation show a consistent non-redundant hyperfunctionality in the context of normal expression of other PLC isoforms. This manifests as enhanced release of cellular calcium ion stores in response to physiologically relevant stimuli like Fc-receptor ligation or exposure to Aβ oligomers. Expression of the PLCγ2-R522 variant resulted in increased stimulus-dependent PIP₂ depletion and reduced basal PIP₂ levels in vivo. Furthermore, it was associated with impaired phagocytosis and enhanced endocytosis. PLCγ2 acts downstream of other AD-related factors, such as TREM2 and CSF1R, and alterations in its activity directly impact cell function. The inherent druggability of enzymes such as PLCγ2 raises the prospect of PLCγ2 manipulation as a future therapeutic approach in AD.

Modest changes in Spi1 dosage reveal the potential for altered microglial function as seen in Alzheimer's disease

Genetic association studies have identified multiple variants at the SPI1 locus that modify risk and age of onset for Alzheimer's Disease (AD). Reports linking risk variants to gene expression suggest that variants denoting higher SPI1 expression are likely to have an earlier AD onset, and several other AD risk genes contain PU.1 binding sites in the promoter region. Overall, this suggests the level of SPI1 may alter microglial phenotype potentially impacting AD. This study determined how the microglial transcriptome was altered following modest changes to Spi1 expression in primary mouse microglia. RNA-sequencing was performed on microglia with reduced or increased Spi1/PU.1 expression to provide an unbiased approach to determine transcriptomic changes affected by Spi1. In summary, a reduction in microglial Spi1 resulted in the dysregulation of transcripts encoding proteins involved in DNA replication pathways while an increased Spi1 results in an upregulation of genes associated with immune response pathways. Additionally, a subset of 194 Spi1 dose-sensitive genes was identified and pathway analysis suggests that several innate immune and interferon response pathways are impacted by the concentration of Spi1. Together these results suggest Spi1 levels can alter the microglial transcriptome and suggests interferon pathways may be altered in individuals with AD related Spi1 risk SNPs.

Family History and Risk of Upper Gastrointestinal Cancer in the Linxian General Population

OBJECTIVE

The objective of this study was to investigate family history (FH) of upper gastrointestinal (UGI) cancer and risk of esophageal squamous cell carcinoma (ESCC), gastric cardia carcinoma (GCC), and gastric non-cardia carcinoma (GNCC) in the Linxian General Population Nutrition Intervention Trial (NIT) cohort. Methods: This prospective analysis was conducted using the Linxian NIT cohort data. Subjects with FH of UGI cancer was treated as an exposed group while the remainders were considered as a comparison group. Hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between FH of UGI cancer and risk of UGI cancer incidence and mortality were estimated using Cox proportional hazards models.

RESULTS

There were 5,680 newly diagnosed UGI cancer cases during the follow-up period, with a total of 4,573 UGI cancer deaths occurred, including 2,603 ESCC, 1,410 GCC, and 560 GNCC deaths. A positive FH of UGI cancer was associated with a significantly increased risk of ESCC and GCC (Incidence: HRESCC = 1.45, 95%CI: 1.35-1.56; HRGCC = 1.27, 95%CI: 1.15-1.40; Mortality: HRESCC = 1.40, 95%CI: 1.30-1.52; HRGCC = 1.27, 95%CI: 1.14-1.42) after adjusting for age at baseline, gender, smoking status, alcohol drinking, education level, and frequency of fresh fruit and vegetable consumption. Subjects with FH in both parents had the highest risk of ESCC and GCC incidence (HRESCC = 1.65, 95%CI: 1.40-1.95; HRGCC = 1.42, 95%CI: 1.12-1.81) and deaths (HRESCC = 1.65, 95%CI: 1.38-1.97; HRGCC = 1.42, 95%CI: 1.09-1.85). Spouse diagnosed with UGI cancer did not increase the risk of any UGI cancers of the subjects. In subgroup analysis, FH of UGI cancer was shown to significantly increase the risk of GCC in non-drinkers (Incidence: HR = 1.31, 95%CI: 1.17-1.47; Mortality: HR = 1.33, 95%CI: 1.17-1.50). No associations were observed for risk of GNCC. Sensitivity analysis by excluding subjects who were followed up less than three years did not materially alter our results.

CONCLUSION

Our data point to the role of the FH of UGI cancer to the risk of ESCC and GCC incidence and mortality. The influence of family history on the risk of UGI cancer varies from different types of family members.

ABO genotypes and the risk of esophageal and gastric cancers

BACKGROUND

Blood type has been associated with the risk of gastric cancer, but few studies have examined the association with esophageal squamous cell carcinoma (ESCC).

METHODS

We conducted a case-control study using genotyping data of Chinese individuals, including cases of 2022 ESCC, 1189 gastric cardia adenocarcinoma, 1161 gastric noncardia adenocarcinoma, and 2696 controls. Genetic blood type was imputed using three single nucleotide polymorphisms. We used logistic regression to examine the association between blood type and the risk of each cancer.

RESULTS

Compared to blood type O, the risk of ESCC was significantly elevated for blood type B and AB, with the highest risk for type AB (OR, 95%CI: 1.34, 1.07-1.67). Analysis of genotype suggested that the association of ESCC was from carrying the B allele. Similarly, blood type was significantly associated with gastric noncardia adenocarcinoma (P < 0.001) with risk significantly elevated in type A (1.37, 1.14-1.65) and AB (1.44, 1.10-1.89) compared to type O. Blood type was not associated with gastric cardia adenocarcinoma (P = 0.13).

CONCLUSIONS

This study provides novel insights into the association between blood type and the risk of ESCC and restricted previously observed association to only gastric noncardia cancer, providing important evidence to clarify the pattern of association and suggesting mechanisms of action.

Low Epstein-Barr Virus Prevalence in Cardia Gastric Cancer Among a High-Incidence Chinese Population

BACKGROUND

Epstein-Barr virus (EBV) positivity is associated with better gastric cancer prognosis and is found in a relatively fixed 9% of tumors worldwide.

AIM

We aimed to examine the EBV status of gastric adenocarcinomas in a very high-incidence population and to compare prevalence between cardia and non-cardia anatomic subsites.

METHODS

We evaluated 1035 adult gastric adenocarcinoma cases presenting during 1997-2005 to the Shanxi Cancer Hospital in Taiyuan, Shanxi Province, China. EBV-encoded RNA was detected in alcohol-fixed paraffin-embedded tumor specimens by in situ hybridization. Associations were assessed in case-case comparisons using the Chi-squared test for categorical variables and the Mann-Whitney U test for continuous variables, with p values < 0.05 considered statistically significant. Adjusted odds ratios were calculated using logistic regression, and mortality hazard ratios (HRs) were estimated by Cox proportional hazards regression.

RESULTS

Sixty-four percent of the evaluated cancers were found in the cardia. Cardia tumor localization was associated with male sex, advanced primary tumor stage, better differentiated histology, and intestinal-type Lauren classification. Four percent of the non-cardia and only 0.9% of cardia cancers were EBV-positive. EBV positivity was associated with better overall survival (adjusted HR 0.30, 95% CI 0.14-0.63).

CONCLUSIONS

Our study highlights unusually low EBV prevalence in gastric adenocarcinoma among a high-incidence population, particularly for cardia cancers. These findings suggest a unique risk factor profile for the high incidence of gastric cancer in this population.

Serum Levels of Androgens, Estrogens, and Sex Hormone Binding Globulin and Risk of Primary Gastric Cancer in Chinese Men: A Nested Case-Control Study

Gastric cancer shows a strong male predominance, and sex steroid hormones have been hypothesized to explain this sex disparity. Previous studies examining the associations between sex hormones and sex hormone binding globulin (SHBG) and risk of gastric cancer come primarily from western populations and additional studies in diverse populations will help us better understand the association. We performed a nested case-control study in Linxian Nutrition Intervention Trials cohorts to evaluate the associations among Chinese men, where we had sufficient cases to perform a well-powered study. Using radioimmunoassays and immunoassays, we quantitated androgens, estrogens, and SHBG in baseline serum from 328 men that developed noncardia gastric cancer and matched controls. We used multivariable unconditional logistic regression to calculate ORs and 95% confidence intervals (CI) and explored interactions with body mass index (BMI), age, alcohol drinking, smoking, and follow-up time. Subjects with SHBG in the highest quartile, as compared with those in the lowest quartile, had a significantly increased risk of gastric cancer (OR = 1.87; 95% CI, 1.01-3.44). We found some evidence for associations of sex steroid hormones in men with lower BMI. Our study found a novel association suggesting that higher serum concentrations of SHBG may be associated with risk of gastric cancer in men. We found no overall associations with sex hormones themselves, but future studies should expand the scope of these studies to include women and further explore whether BMI modifies a potential association. PREVENTION RELEVANCE: It was the first study to investigate the association of gastric cancer with prediagnostic sex steroid hormones and SHBG in an Asian male population. Although there were no overall associations for sex steroid hormone concentrations, higher concentrations of SHBG was associated with increased risk of noncardia gastric cancer.

Dependence on Mincle and Dectin-2 Varies With Multiple Candida Species During Systemic Infection

More than 95% of invasive Candida infections are caused by four Candida spp. (C. albicans, C. glabrata, C. tropicalis, C. parapsilosis). C-type lectin-like receptors (CLRs), such as Dectin-1, Dectin-2, and Mincle mediate immune responses to C. albicans. Dectin-1 promotes clearance of C. albicans, C. glabrata, C. tropicalis, and C. parapsilosis, however, dependence on Dectin-1 for specific immune responses varies with the different Candida spp. Dectin-2 is important for host immunity to C. albicans and C. glabrata, and Mincle is important for the immune response to C. albicans. However, whether Dectin-2 drives host immunity to C. tropicalis or C. parapsilosis, and whether Mincle mediates host immunity to C. glabrata, C. tropicalis or C. parapsilosis is unknown. Therefore, we compared the roles of Dectin-2 and Mincle in response to these four Candida spp. We demonstrate that these four Candida spp. cell walls have differential mannan contents. Mincle and Dectin-2 play a key role in regulating cytokine production in response to these four Candida spp. and Dectin-2 is also important for clearance of all four Candida spp. during systemic infection. However, Mincle was only important for clearance of C. tropicalis during systemic infection. Our data indicate that multiple Candida spp. have different mannan contents, and dependence on the mannan-detecting CLRs, Mincle, and Dectin-2 varies between different Candida spp. during systemic infection.

Macrophage reprogramming for therapy

Dysfunction of the immune system underlies a plethora of human diseases, requiring the development of immunomodulatory therapeutic intervention. To date, most strategies employed have been focusing on the modification of T lymphocytes, and although remarkable improvement has been obtained, results often fall short of the intended outcome. Recent cutting-edge technologies have highlighted macrophages as potential targets for disease control. Macrophages play central roles in development, homeostasis and host defence, and their dysfunction and dysregulation have been implicated in the onset and pathogenesis of multiple disorders including cancer, neurodegeneration, autoimmunity and metabolic diseases. Recent advancements have led to a greater understanding of macrophage origin, diversity and function, in both health and disease. Over the last few years, a variety of strategies targeting macrophages have been developed and these open new therapeutic opportunities. Here, we review the progress in macrophage reprogramming in various disorders and discuss the potential implications and challenges for macrophage-targeted approaches in human disease.

Colorectal cancer in the Linxian China Nutrition Intervention Trial: Risk factors and intervention results

BACKGROUND

Colorectal cancer (CRC) is among the most common cancers in economically developed countries and developing world. While dietary factors are associated with risk of CRC in the West and urban China, little is known about risk or protective factors in rural China.

METHODS

The Linxian General Population Nutrition Intervention Trial (NIT) cohort was established over 30 years ago to test whether daily multivitamin/mineral supplements could reduce the incidence and mortality of esophageal/gastric cardia cancer. The cohort included a total of 29,553 healthy participants 40-69 years old who were randomly assigned to supplements or placebos via a 24 fractional factorial study design. We examined risk factors for the development of CRC as well as the effects of four different nutritional factors (Factor A: retinol, zinc; B: riboflavin, niacin; C: ascorbic acid, molybdenum; D: selenium, alpha-tocopherol, beta-carotene,) on CRC incidence following 5.25 years of supplementation in this randomized, placebo-controlled intervention trial.

RESULTS

CRC risk increased with age and height as well as piped water usage, family history of CRC, and consumption of foods cooked in oil, eggs, and fresh fruits. No effect on CRC was seen for any of these four intervention factors tested in both genders, but CRC was reduced 37% in females who received Factor D (selenium/alpha-tocopherol/beta-carotene) (RR = 0.63, 95% CI = 0.43-0.92, P = 0.016) compared to females who did not receive Factor D.

CONCLUSIONS

In this undernourished rural Chinese population, CRC risk factors in this Chinese cohort showed both similarities and differences compared to Western and urban Asian Chinese populations. Intervention results suggested a potential benefit for women supplemented with selenium/alpha-tocopherol/beta-carotene.

Selenium Kinetics in Humans Change Following 2 Years of Supplementation With Selenomethionine

BACKGROUND

Selenium (Se) is a nutritionally essential trace element and health may be improved by increased Se intake. Previous kinetic studies have shown differences in metabolism of organic vs. inorganic forms of Se [e.g., higher absorption of selenomethionine (SeMet) than selenite (Sel), and more recycling of Se from SeMet than Sel]. However, the effects on Se metabolism after prolonged Se supplementation are not known.

OBJECTIVE

To determine how the metabolism and transport of Se changes in the whole-body in response to Se-supplementation by measuring Se kinetics before and after 2 years of Se supplementation with SeMet.

METHODS

We compared Se kinetics in humans [n = 31, aged 40 ± 3 y (mean ± SEM)] studied twice after oral tracer administration; initially (PK1), then after supplementation for 2 y with 200 µg/d of Se as selenomethionine (SeMet) (PK2). On each occasion, we administered two stable isotope tracers of Se orally: SeMet, the predominant food form, and selenite (Na₂⁷⁶SeO_3, or Sel), an inorganic form. Plasma and RBC were sampled for 4 mo; urine and feces were collected for the initial 12 d of each period. Samples were analyzed for tracers and total Se by isotope dilution GC-MS. Data were analyzed using a compartmental model, we published previously, to estimate fractional transfer between pools and pool masses in PK2.

RESULTS

We report that fractional absorption of SeMet or Sel do not change with SeMet supplementation and the amount of Se absorbed increased. The amount of Se excreted in urine increases but does not account for all the Se absorbed. As a result, there is a net incorporation of SeMet into various body pools. Nine of the 11 plasma pools doubled in PK2; two did not change. Differences in metabolism were observed for SeMet and Sel; RBC uptake increased 247% for SeMet, urinary excretion increased from two plasma pools for Sel and from two different pools for SeMet, and recycling to liver/tissues increased from one plasma pool for Sel and from two others for SeMet. One plasma pool increased more in males than females in PK2.

CONCLUSIONS

Of 11 Se pools identified kinetically in human plasma, two did not increase in size after SeMet supplementation. These pools may be regulated and important during low Se intake.

Oral leukoplakia and the long-term risk of upper gastrointestinal cancer deaths in the Linxian dysplasia population

BACKGROUND

To investigate oral leukoplakia (OL) and risk of upper gastrointestinal (UGI) cancer deaths in the Linxian Dysplasia Nutrition Intervention Trial (NIT) cohort.

METHODS

A total of 3318 subjects with esophageal squamous dysplasia enrolled on 1 May 1985, and were followed up until 30 September 2015. Participants with OL at baseline were treated as an exposed group, while the remainder was selected as a control group. All subjects were followed monthly and reviewed quarterly by the Linxian Cancer Registry. Cox proportional hazard model was used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs).

RESULTS

During the 30-year follow-up, a total of 902 UGI cancer deaths occurred, including 541 esophageal squamous cell carcinoma (ESCC) related, 284 gastric cardia carcinoma (GCC) related, and 77 gastric noncardia carcinoma (GNCC) related deaths. Relative to subjects without OL, the long-term risk of ESCC mortality in participants with OL increased by 26.1% (HR = 1.26, 95% CI: 1.05-1.52). In the subgroup analyses, adverse effects of OL on ESCC mortality were observed especially in younger subjects (HR = 1.48, 95% CI: 1.11-1.97), females (HR = 1.44, 95% CI: 1.11-1.89), non-smokers (HR = 1.44, 95% CI: 1.15-1.81), nondrinkers (HR = 1.28, 95% CI: 1.04-1.57), and individuals with a family history of cancer (HR = 1.37, 95% CI: 1.05-1.79). No associations were observed between OL and risk of GCC and GNCC mortality.

CONCLUSIONS

OL may increase the long-term risk of ESCC mortality, especially in younger subjects, females, nondrinkers, non-smokers, and subjects with a family cancer history. Future studies are needed to explore the potentially etiological mechanism.

Methylated DNA Markers of Esophageal Squamous Cancer and Dysplasia: An International Study

BACKGROUND

Discovery of methylated DNA markers (MDM) of esophageal squamous cell carcinoma (ESCC) has sparked interest in assessing these markers in tissue. We evaluated MDMs in ESCC from three geographically and ethnically distinct populations, and explored the feasibility of assaying MDMs from DNA obtained by swallowed balloon devices.

METHODS

MDMs were assayed in ESCC and normal tissues obtained from the populations of United States, Iran, and China, and from exfoliative cytology specimens obtained by balloons in a Chinese population. Areas under the receiver operating curve (AUC) of MDMs discriminating ESCC from normal tissues were calculated. Random forest prediction models were built, trained on U.S. cases and controls, and calibrated to U.S.-only controls (model 1) and three-country controls (model 2). Statistical tests were used to assess the relationship between dysplasia and MDM levels in balloons.

RESULTS

Extracted DNA from 333 ESCC and 322 normal tissues was analyzed, in addition to archival DNA from 98 balloons. For ESCC, model 1 validated in Iranian and Chinese tissues with AUCs of 0.90 and 0.87, and model 2 yielded AUCs of 0.99, 0.96, and 0.94 in tissues from the United States, Iran, and China, respectively. In Chinese balloons, MDMs showed a statistically significant trend of increasing levels with increasing grades of dysplasia (P < 0.004).

CONCLUSIONS

MDMs accurately discriminate ESCC from normal esophagus in tissues obtained from high- and low-incidence countries. Preliminary data suggest that levels of MDMs assayed in DNA from swallowed balloon devices increase with dysplasia grade. Larger studies are needed to validate these results.

IMPACT

MDMs coupled with minimally invasive collection methods have the potential for worldwide application in ESCC screening.

Independent and Joint Associations between Serum Calcium, 25-Hydroxy Vitamin D, and the Risk of Primary Liver Cancer: A Prospective Nested Case-Control Study

BACKGROUND

Accumulating evidence has shown that serum calcium and vitamin D may be associated with or influence various cancer risks. However, no prospective studies have evaluated the independent and joint associations between prediagnostic levels of serum calcium and vitamin D and future risk of incident primary liver cancer.

METHODS

We used a nested case-control design to evaluate subjects over 22 years of follow-up. Serum calcium, 25-hydroxy vitamin D [25(OH)D], and three markers of hepatitis B virus and hepatitis C virus were measured in baseline serum from 226 incident primary liver cancer cases and 1,061 matched controls. We calculated ORs and 95% confidence intervals (CI) using logistic regression to estimate the associations between calcium, 25(OH)D, and primary liver cancer risk.

RESULTS

Multivariable adjusted models showed that subjects with both low (OR_Low/Medium = 1.48, 95% CI = 1.01-2.17) or high (OR_High/Medium = 1.92, 95% CI = 1.34-2.76) calcium had an increased primary liver cancer risk, while those with high 25(OH)D had a decreased risk of primary liver cancer (OR_High/Medium = 0.54, 95% CI = 0.35-0.82). In joint analyses, when compared with subjects with medium calcium and 25(OH)D, subjects with high calcium and medium 25(OH)D had elevated odds of developing primary liver cancer (OR = 1.89, 95% CI = 1.17-3.05); those with medium calcium and high 25(OH)D had reduced odds of developing primary liver cancer (OR = 0.34, 95% CI = 0.17-0.67); and subjects in other classifications of calcium and serum 25(OH)D levels had no change in the odds of developing primary liver cancer (all P > 0.05).

CONCLUSIONS

In a nutrient-deficient population, we found that serum calcium and serum 25(OH)D could potentially be modifiable risk or protective factors.

IMPACT

Our findings provide potential targets for primary liver cancer prevention and control.

Fresh fruit consumption may decrease the long-term risk of esophageal cancer mortality: A 30-year follow-up study in the Linxian Dysplasia Nutrition Intervention trial (NIT)

BACKGROUND

The objective of this study was to explore the association between fresh fruit consumption and long-term risk of upper gastrointestinal cancer (UGI) in the Linxian Dysplasia Nutrition Intervention Trial (NIT) cohort.

METHODS

A cohort of 3318 subjects with esophageal squamous dysplasia participated in the Linxian Dysplasia NIT in May 1985 and were followed up until 30 September 2015. Demographic characteristics, lifestyle, and history of diseases were collected at the baseline. The primary endpoint was death from esophageal squamous cell carcinoma (ESCC), gastric cardia carcinoma (GCC), and gastric noncardia carcinoma (GNCC). Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were estimated using the Cox proportional hazard model.

RESULTS

In the 30-year follow-up, a total of 541 ESCC, 284 GCC, and 77 GNCC deaths occurred. Relative to those who never or rarely consumed fresh fruit, the risk of ESCC mortality in participants who consumed fresh fruit more than 12 times/year were significantly decreased by 37.3% (HR = 0.63, 95% CI: 0.49-0.81). In the subgroup analyses, significantly protective effects on ESCC mortality were observed especially in females (HR = 0.59, 95% CI: 0.40-0.89), non-smokers (HR = 0.67, 95% CI: 0.48-0.94), and nondrinkers (HR = 0.69, 95% CI: 0.51-0.93).

CONCLUSIONS

Consuming fresh fruit more than 12 times/year may reduce the long-term risk of ESCC mortality in this dysplasia population, particularly in females, non-smokers, and nondrinkers. Future studies are needed to confirm these findings.

Tissue-resident macrophages actively suppress IL-1beta release via a reactive prostanoid/IL-10 pathway

The alarm cytokine interleukin‐1β (IL‐1β) is a potent activator of the inflammatory cascade following pathogen recognition. IL‐1β production typically requires two signals: first, priming by recognition of pathogen‐associated molecular patterns leads to the production of immature pro‐IL‐1β; subsequently, inflammasome activation by a secondary signal allows cleavage and maturation of IL‐1β from its pro‐form. However, despite the important role of IL‐1β in controlling local and systemic inflammation, its overall regulation is still not fully understood. Here we demonstrate that peritoneal tissue‐resident macrophages use an active inhibitory pathway, to suppress IL‐1β processing, which can otherwise occur in the absence of a second signal. Programming by the transcription factor Gata6 controls the expression of prostacyclin synthase, which is required for prostacyclin production after lipopolysaccharide stimulation and optimal induction of IL‐10. In the absence of secondary signal, IL‐10 potently inhibits IL‐1β processing, providing a previously unrecognized control of IL‐1β in tissue‐resident macrophages.

Integrated analysis of genome-wide miRNAs and targeted gene expression in esophageal squamous cell carcinoma (ESCC) and relation to prognosis

Background

Esophageal squamous cell carcinoma (ESCC) is a leading cause of cancer death worldwide and in China. We know miRNAs influence gene expression in tumorigenesis, but it is unclear how miRNAs affect gene expression or influence survival at the genome-wide level in ESCC.

Methods

We performed miRNA and mRNA expression arrays in 113 ESCC cases with tumor/normal matched tissues to identify dysregulated miRNAs, to correlate miRNA and mRNA expressions, and to relate miRNA and mRNA expression changes to survival and clinical characteristics.

Results

Thirty-nine miRNAs were identified whose tumor/normal tissue expression ratios showed dysregulation (28 down- and 11 up-regulated by at least two-fold with P < 1.92E-04), including several not previously reported in ESCC (miR-885-5p, miR-140-3p, miR-708, miR-639, miR-596). Expressions of 16 miRNAs were highly correlated with expressions of 195 genes (P < 8.42E-09; absolute rho values 0.51–0.64). Increased expressions of miRNA in tumor tissue for both miR-30e* and miR-124 were associated with increased survival (P < 0.05). Similarly, nine probes in eight of 818 dysregulated genes had RNA expression levels that were nominally associated with survival, including NF1, ASXL1, HSPA4, TGOLN2, BAIAP2, EZH2, CHAF1A, SUPT7L.

Conclusions

Our characterization and integrated analysis of genome-wide miRNA and gene expression in ESCC provides insights into the expression of miRNAs and their relation to regulation of RNA targets in ESCC tumorigenesis, and suggest opportunities for the future development of miRs and mRNAs as biomarkers for early detection, diagnosis, and prognosis in ESCC.

Associations Between Prediagnostic Concentrations of Circulating Sex Steroid Hormones and Esophageal/Gastric Cardia Adenocarcinoma Among Men

Background

Esophageal adenocarcinoma (EA) and gastric cardia adenocarcinoma (GCA) are characterized by a strong male predominance. Concentrations of sex steroid hormones have been hypothesized to explain this sex disparity. However, no prospective population-based study has examined sex steroid hormones in relation to EA/GCA risk. Thus, we investigated whether prediagnostic circulating sex steroid hormone concentrations were associated with EA/GCA in a nested case-control study drawn from participants in three prospective cohort studies.

Methods

Using gas chromatography-mass spectrometry (GC-MS) and electrochemiluminescence immunoassay, we quantitated sex steroid hormones and sex hormone binding globulin, respectively, in serum from 259 EA/GCA male case participants and 259 matched male control participants from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial, Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study, and Cancer Prevention Study II Nutrition Cohort. Multivariable conditional logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for associations between circulating hormones and EA/GCA risk. All statistical tests were two-sided.

Results

Higher concentrations of dehydroepiandrosterone (DHEA) were associated with a 38% decreased risk of EA/GCA (OR per unit increase in log2 DHEA = 0.62, 95% CI = 0.47 to 0.82, Ptrend = .001). Higher estradiol concentrations were associated with a 34% reduced risk of EA/GCA (OR = 0.66, 95% CI = 0.45 to 0.98, Ptrend = .05), and the association with free estradiol was similar. No other associations between baseline hormone concentrations and future EA/GCA risk were observed.

Conclusions

This study provides the first evidence that higher concentrations of circulating DHEA, estradiol, and free estradiol may be associated with lower risks of EA/GCA in men.

Body mass index and risk of upper gastrointestinal cancer: A 30-year follow-up of the Linxian dysplasia nutrition intervention trial cohort

BACKGROUND

Although a number of previous studies have noted the association between body mass index (BMI) and upper gastrointestinal (UGI) cancer risk, little evidence exists in the Chinese esophageal squamous dysplasia population. This prospective study investigated the association between BMI and UGI cancer risk in the Linxian Dysplasia Nutrition Intervention Trial (NIT) cohort.

METHODS

A total of 3298 participants were included in the final analysis. Asian-specific BMI cut-offs were used to define BMI subgroups: underweight <18.5 kg/m², normal ≥18.5 to <24 kg/m² and overweight or obese ≥24 kg/m². Hazard ratios (HRs) and 95 % confidence intervals (95 %CIs) were estimated using the Cox proportional hazard model.

RESULTS

During over 30 years of follow-up we identified 654 incident esophageal squamous-cell carcinoma (ESCC) cases and 434 gastric cancer cases which included 88 gastric non-cardia carcinoma (GNCC) and 346 gastric cardia carcinoma (GCC) cases. Relative to normal weight, overweight or obesity were associated with a significantly reduced risk of ESCC (HR 0.69, 95 %CI 0.48-0.98) after multivariate adjustment, including age at baseline, gender, smoking, drinking, family history of cancer, education and consumption of fresh fruit. Subgroup analyses found that clear effects were evident in women and subjects with a family history of cancer. No association with gastric cancer was observed in any subjects or subgroups.

CONCLUSION

Overweight/obesity was associated with decreased risk of ESCC in this dysplasia population, particularly in women and persons who had a family history of cancer. Future studies are needed to confirm these findings.

The U-shaped association between body mass index and gastric cancer risk in the Helicobacter pylori Biomarker Cohort Consortium: A nested case-control study from eight East Asian cohort studies

The association between body mass index (BMI) and noncardia gastric cancer (NCGC) risk remains controversial. The purpose of our study was to examine the association of BMI with NCGC risk with consideration of Helicobacter pylori (HP) biomarkers. This international nested case-control study, composed of 1,591 incident NCGC cases and 1,953 matched controls, was established from eight cohorts in China, Japan and Korea, where the majority of NCGCs are diagnosed worldwide. HP antibody biomarkers were measured in blood collected at cohort enrollment by multiplex serology. The NCGC risk according to baseline BMI was estimated using logistic regression to produce odds ratios (ORs) and 95% confidence intervals (CIs). We found a U-shaped association between BMI category and NCGC risk. Compared to those with reference BMI (22.6-25.0 kg/m² ), those with lower and higher BMI had an increased NCGC risk (BMI <18.5 kg/m² , OR = 1.56, 95% CI = 1.04-2.34; BMI >27.5 kg/m² , OR = 1.48, 95% CI = 1.15-1.91; adjusted for age, sex and smoking). The U-shaped association was persistent among subjects with HP infection and high-risk biomarkers (HP+ CagA+: BMI <18.5 kg/m² , OR = 1.60, 95% CI = 1.00-2.55; BMI >27.5 kg/m² , OR = 1.59, 95% CI = 1.21-2.11; and Omp+ HP0305+: BMI <18.5 kg/m² , OR = 1.88, 95% CI = 1.04-3.42; BMI >27.5 kg/m² , OR = 1.70, 95% CI = 1.20-2.42, respectively). Our study provides evidence of significantly increased NCGC risk among individuals with low or high BMI, including in subjects with high-risk HP biomarkers (HP+ CagA+, Omp+ HP0305+) in the high-risk area of East Asia.

Effective In Vivo Gene Modification in Mouse Tissue-Resident Peritoneal Macrophages by Intraperitoneal Delivery of Lentiviral Vectors

Tissue-resident macrophages exhibit specialized phenotypes dependent on their in vivo physiological niche. Investigation of their function often relies upon complex whole mouse transgenic studies. While some appropriate lineage-associated promoters exist, there are no options for tissue-specific targeting of macrophages. We have developed full protocols for in vivo productive infection (defined by stable transgene expression) of tissue-resident macrophages with lentiviral vectors, enabling RNA and protein overexpression, including expression of small RNA species such as shRNA, to knock down and modulate gene expression. These approaches allow robust infection of peritoneal tissue-resident macrophages without significant infection of other cell populations. They permit rapid functional study of macrophages in homeostatic and inflammatory settings, such as thioglycolate-induced peritonitis, while maintaining the cells in their physiological context. Here we provide detailed protocols for the whole workflow: viral production, purification, and quality control; safety considerations for administration of the virus to mice; and assessment of in vivo transduction efficiency and the low background levels of inflammation induced by the virus. In summary, we present a quick and accessible protocol for the rapid assessment of gene function in peritoneal tissue-resident macrophages in vivo.

Effects of Nutrition Intervention on Total and Cancer Mortality: 25-Year Post-trial Follow-up of the 5.25-Year Linxian Nutrition Intervention Trial

Background

A beneficial effect of supplementation with selenium, vitamin E, and beta-carotene was observed on total and cancer mortality in a Chinese population, and it endured for 10 years postintervention, but longer durability is unknown.

Methods

A randomized, double-blind, placebo-controlled trial was conducted in Linxian, China, from 1986 to 1991; 29 584 residents age 40 to 69 years received daily supplementations based on a factorial design: Factors A (retinol/zinc), B (riboflavin/niacin), C (vitamin C/molybdenum), and/or D (selenium/vitamin E/beta-carotene), or placebo for 5.25 years, and followed for up 25 years. Hazard ratios (HRs) and 95% confidence intervals (CIs) for the intervention effects on mortalities were estimated using Cox proportional hazards models.

Results

Through 2016, the interventions showed no effect on total mortality. The previously reported protective effect of Factor D against total mortality was lost 10 years postintervention. The protective effect of Factor D for gastric cancer was attenuated (HR = 0.93, 95% CI = 0.85 to 1.01), but a newly apparent protective effect against esophageal cancer was found for Factor B (HR = 0.92, 95% CI = 0.85 to 1.00, two-sided P = .04). Other protective/adverse associations were observed for cause-specific mortalities. Protective effects were found in people younger than age 55 years at baseline against non-upper gastrointestinal cancer death for Factor A (HR = 0.80, 95% CI = 0.69 to 0.92) and against death from stroke for Factor C (HR = 0.89, 95% CI = 0.82 to 0.96). In contrast, increased risk of esophageal cancer was found when the intervention began after age 55 years for Factors C (HR = 1.16, 95% CI = 1.04 to 1.30) and D (HR = 1.20, 95% CI = 1.07 to 1.34).

Conclusions

Multiyear nutrition intervention is unlikely to have a meaningful effect on mortality more than a decade after supplementation ends, even in a nutritionally deprived population. Whether sustained or repeat intervention would provide longer effects needs further investigation.

Serologic Profile of Antiparietal Cell Antibodies, Pepsinogens, and H. pylori and Risk of Upper Gastrointestinal Cancer: A Nested Case-Control Study in China

BACKGROUND

Autoimmune gastritis is understudied and possibly associated with gastric noncardia adenocarcinoma (GNCA) and esophageal squamous cell carcinoma (ESCC) in Western populations when it presents as pernicious anemia.

METHODS

A nested case-control study within a Chinese cohort included 100 ESCC, 200 gastric cardia adenocarcinoma (GCA), and 200 GNCA cases diagnosed between 1986 and 2001 and 400 controls. Serostatus of antiparietal cell antibodies (APCA), Helicobacter pylori antibodies, and pepsinogens were measured using commercial kits and serum collected at baseline. We used logistic regression to calculate odds ratios (OR) and 95% confidence interval (CI) for associations between serologic biomarkers and cancer risk adjusted for numerous potential confounders.

RESULTS

There was an average interval of 8 years between baseline blood draw and cancer diagnosis. The baseline prevalence of APCA seropositivity was 10.0% and 14.5% in subjects who developed GCA and GNCA, respectively. APCA seropositivity was inversely associated with later development of GCA (OR = 0.42; 95% CI, 0.24-0.75), but not significantly associated with later development of GNCA (OR = 0.82; 95% CI, 0.50-1.36) or ESCC (OR = 1.05; 95% CI, 0.58-1.88). APCA seropositivity was significantly associated with low pepsinogen I/II ratios (OR = 3.69; 95% CI, 1.66-8.21), and individuals with low pepsinogen I/II ratios who were seronegative for APCA had the highest risk of both GCA and GNCA.

CONCLUSIONS

APCA seropositivity measured years prior to diagnosis was associated with prevalent atrophic gastritis but inversely associated with incident GCA in this Chinese population.

IMPACT

APCA may contribute to a growing list of serologic markers that can improve risk stratification for gastric cancer.

Dependence on Dectin-1 Varies With Multiple Candida Species

Four Candida spp. (albicans, glabrata, tropicalis, parapsilosis) cause >95% of invasive Candida infections. C. albicans elicits immune responses via pathogen recognition receptors including C-type lectin-like receptors (CLRs). The CLR, Dectin-1 is important for host immunity to C. albicans and C. glabrata, however, whether Dectin-1 is important for host defense against C. tropicalis or C. parapsilosis is unknown. Therefore, we compared the involvement of Dectin-1 in response to these four diverse Candida spp. We found that Dectin-1 mediates innate cytokine responses to these Candida spp. in a species- and cell-dependent manner. Dectin-1 KO mice succumbed to infection with highly virulent C. albicans while they mostly survived infection with less virulent Candida spp. However, Dectin-1 KO mice displayed increased fungal burden following infection with each Candida spp. Additionally, T cells from Dectin-1 KO mice displayed enhanced effector functions likely due to the inability of Dectin-1 KO mice to clear the infections. Together, these data indicate that Dectin-1 is important for host defense to multiple Candida spp., although the specific roles for Dectin-1 varies with different Candida spp.

Development and characterization of novel anti-C5 monoclonal antibodies capable of inhibiting complement in multiple species

Over the last decade there has been an explosion in complement therapies; one-third of the drugs in the clinic or in development target C5 protein. Eculizumab, a monoclonal antibody (mAb) that binds C5 and blocks its cleavage by the convertase, is the current reference standard treatment for atypical haemolytic uraemic syndrome (aHUS) and paroxysmal nocturnal haemoglobinuria (PNH) and in clinical trials for many other diseases. Here we describe a panel of novel anti-C5 mAb, including mAb that, like Eculizumab, are efficient inhibitors of complement but, unlike Eculizumab, inhibit across species, including human, rat, rabbit and guinea pig. Several inhibitory anti-C5 mAb were identified and characterized for C5 binding and lytic inhibitory capacity in comparison to current therapeutic anti-C5 mAb; three clones, 4G2, 7D4 and 10B6, were selected and further characterized for ligand specificity and affinity and cross-species inhibitory activity. The mAb 10B6 was human-specific whereas mAb 4G2 and 7D4 efficiently inhibited lysis by human, rabbit and rat serum, and weakly inhibited guinea pig complement; 7D4 also weakly inhibited mouse complement in vitro The rat C5-cross-reactive mAb 4G2, when administered intraperitoneally in a rat model of myasthenia gravis, effectively blocked the disease and protected muscle endplates from destruction. To our knowledge this is the first report of an anti-C5 function blocking mAb that permits preclinical studies in rats.

The protective effect of inflammatory monocytes during systemic C. albicans infection is dependent on collaboration between C-type lectin-like receptors

Invasive candidiasis, mainly caused by Candida albicans, is a serious healthcare problem with high mortality rates, particularly in immunocompromised patients. Innate immune cells express pathogen recognition receptors (PRRs) including C-type lectin-like receptors (CLRs) that bind C. albicans to initiate an immune response. Multiple CLRs including Dectin-1, Dectin-2 and Mincle have been proposed individually to contribute to the immune response to C. albicans. However how these receptors collaborate to clear a fungal infection is unknown. Herein, we used novel multi-CLR knockout (KO) mice to decipher the individual, collaborative and collective roles of Dectin-1, Dectin-2 and Mincle during systemic C. albicans infection. These studies revealed an unappreciated and profound role for CLR co-operation in anti-fungal immunity. The protective effect of multiple CLRs was markedly greater than any single receptor, and was mediated through inflammatory monocytes via recognition and phagocytosis of C. albicans, and production of C. albicans-induced cytokines and chemokines. These CLRs were dispensable for mediating similar responses from neutrophils, likely due to lower expression of these CLRs on neutrophils compared to inflammatory monocytes. Concurrent deletion of Dectin-1 and Dectin-2, or all three CLRs, resulted in dramatically increased susceptibility to systemic C. albicans infection compared to mice lacking a single CLR. Multi-CLR KO mice were unable to control fungal growth due to an inadequate early inflammatory monocyte-mediated response. In response to excessive fungal growth, the multi-CLR KO mice mounted a hyper-inflammatory response, likely leading to multiple organ failure. Thus, these data reveal a critical role for CLR co-operation in the effective control of C. albicans and maintenance of organ function during infection.

Fungal infections including invasive candidiasis are a serious healthcare problem particularly for immunocompromised patients. Mortality rates for invasive candidiasis are very high and complex anti-fungal immune responses are poorly understood, hindering the development of novel immunotherapies. Dectin-1, Dectin-2 and Mincle are three cell surface receptors that are proposed to be involved in the immune response to fungal pathogens. However, if or how these receptors work together during infection is currently unknown. Here we demonstrate that these receptors, in particular Dectin-1 and Dectin-2, work together to promote fungal clearance by a group of innate immune cells called inflammatory monocytes. Furthermore, we found that mice lacking these three receptors are dramatically susceptible to systemic Candida albicans infection due to defective early innate immune responses. These mice develop hyper-inflammation to try to control excessive fungal growth likely resulting in multi-organ failure. Our work helps explain how these receptors work together to clear/control invasive candidiasis. Our improved knowledge of the interactions between these receptors could be used to help design novel anti-fungal immunotherapies.

Association between tooth loss and upper gastrointestinal cancer: A 30-year follow-up of the Linxian Dysplasia Nutrition Intervention Trial Cohort

Background

This prospective study investigated the association between tooth loss and upper gastrointestinal (UGI) cancer mortality in the Linxian Dysplasia Nutrition Intervention Trial Cohort.

Methods

Subjects were categorized into three groups according to age at baseline. No missing teeth and less or greater than median tooth loss in each group was defined as none, moderate, and severe, respectively. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were estimated using the Cox proportional hazard model.

Results

Through 30 September 2015, 541 esophageal squamous cell carcinoma (ESCC), 284 gastric cardia carcinoma (GCC), and 77 gastric non‐cardia carcinoma (GNCC) deaths occurred. In the six‐year follow‐up, severe tooth loss was associated with an increased risk of GCC mortality (HR 1.55, 95% CI 1.06–2.18). In the 15‐year follow‐up, moderate tooth loss increased the ESCC mortality risk by 58% (HR 1.58, 95% CI 1.06–2.35), while severe loss increased the GCC mortality risk by 30% (HR 1.30, 95% CI 1.03–1.64). In the 30‐year follow‐up, moderate tooth loss increased the risk of ESCC mortality (HR 1.34, 95% CI 1.01–1.76). In subjects aged < 55 at baseline and men, moderate tooth loss had 53% and 52% higher risks of ESCC mortality (HR_{<55 years} 1.53, 95% CI 1.06–2.05; HRmen 1.52, 95% CI 1.01–2.28). No significant association was observed for GNCC in any subjects or subgroups.

Conclusion

Moderate tooth loss increased the risk of ESCC mortality, particularly in younger subjects and men. Severe tooth loss increased the risk of GCC mortality. Future studies are needed to confirm these findings.

Structural and Functional Analyses of the Shedding Protease ADAM17 in HoxB8-Immortalized Macrophages and Dendritic-like Cells

A disintegrin and metalloproteinase (ADAM) 17 has been implicated in many shedding processes. Major substrates of ADAM17 are TNF-α, IL-6R, and ligands of the epidermal growth factor receptor. The essential role of the protease is emphasized by the fact that ADAM17 deficiency is lethal in mice. To study ADAM17 function in vivo, we generated viable hypomorphic ADAM17 mice called ADAM17ex/ex mice. Recent studies indicated regulation of proteolytic ADAM17 activity by cellular processes such as cytoplasmic phosphorylation and removal of the prodomain by furin cleavage. Maturation and thus activation of ADAM17 is not fully understood. So far, studies of ADAM17 maturation have been mainly limited to mouse embryonic fibroblasts or transfected cell lines relying on nonphysiologic stimuli such as phorbol esters, thus making interpretation of the results difficult in a physiologic context. In this article, we present a robust cell system to study ADAM17 maturation and function in primary cells of the immune system. To this end, HoxB8 conditionally immortalized macrophage precursor cell lines were derived from bone marrow of wild-type and hypomorphic ADAM17ex/ex mice, which are devoid of measurable ADAM17 activity. ADAM17 mutants were stably expressed in macrophage precursor cells, differentiated to macrophages under different growth factor conditions (M-CSF versus GM-CSF), and analyzed for cellular localization, proteolytic activity, and podosome disassembly. Our study reveals maturation and activity of ADAM17 in a more physiological-immune cell system. We show that this cell system can be further exploited for genetic modifications of ADAM17 and for studying its function in immune cells.

Association of tooth loss with liver cancer incidence and chronic liver disease mortality in a rural Chinese population

BACKGROUND

Tooth loss has been reported to be associated with the risk of liver cancer in several prior studies in economically advantaged countries. Whether this relationship is also evident in economically disadvantaged populations is not known.

METHODS

We analyzed data from the Nutrition Intervention Trials, two randomized placebo-controlled trials of vitamin/mineral supplementation in Linxian, China. Participants who reported having lost permanent teeth were examined to determine the number of teeth remaining. In the 30-year follow-up period, 329 liver cancers were diagnosed and 368 chronic liver disease deaths occurred. Tooth loss was categorized based on loess smoothed age-specific predicted quartiles. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the two outcomes.

RESULTS

Overall, persons in the highest quartile of age-specific tooth loss had an increased risk of liver cancer (HR = 1.27, 95%CI: 0.96, 1.67) which was not statistically significant. Results varied by sex and body mass index (BMI), however. Women in the highest quartile of age-specific tooth loss had a significantly increased risk (HR = 1.64, 95%CI: 1.04, 2.59), while men did not (HR = 1.08, 95%CI = 0.75, 1.57), and persons with a BMI > 23.0 kg/m2 (HR = 1.71, 95%CI: 1.00, 2.92) had a significantly increased risk, while persons with a BMI <23.0 kg/m2 did not (HR = 1.14, 95%CI: 0.82, 1.5). No relationships with chronic liver disease mortality were observed.

CONCLUSIONS

In a rural, economically disadvantaged population, persons with the highest levels of age-specific tooth loss had an increased risk of liver cancer. The results, which were stronger among women and persons with greater BMI, suggest that periodontal disease may increase risk of liver cancer.