High fractional excretion of glycation adducts is associated with subsequent early decline in renal function in type 1 diabetes

Increased protein glycation, oxidation and nitration is linked to the development of diabetic nephropathy. We reported levels of serum protein glycation, oxidation and nitration and related hydrolysis products, glycation, oxidation and nitration free adducts in patients with type 1 diabetes (T1DM) during onset of microalbuminuria (MA) from the First Joslin Kidney Study, a prospective case–control study of patients with T1DM with and without early decline in GFR. Herein we report urinary excretion of the latter analytes and related fractional excretion values, exploring the link to MA and early decline in GFR. We recruited patients with T1DM and normoalbuminuria (NA) (n = 30) or new onset MA with and without early GFR decline (n = 22 and 33, respectively) for this study. We determined urinary protein glycation, oxidation and nitration free adducts by stable isotopic dilution analysis liquid chromatography-tandem mass spectrometry (LC–MS/MS) and deduced fractional excretion using reported plasma levels and urinary and plasma creatinine estimates. We found urinary excretion of pentosidine was increased ca. twofold in patients with MA, compared to normoalbuminuria (0.0442 vs 0.0103 nmol/mg creatinine, P < 0.0001), and increased ca. threefold in patients with early decline in GFR, compared to patients with stable GFR (0.0561 vs 0.0176 nmol/mg creatinine, P < 0.01). Urinary excretion of all other analytes was unchanged between the study groups. Remarkably, fractional excretions of 6 lysine and arginine-derived glycation free adducts were higher in patients with early decline in GFR, compared to those with stable GFR. Impaired tubular reuptake of glycation free adducts by lysine and arginine transporter proteins in patients with early GFR decline is likely involved. We conclude that higher fractional excretions of glycation adducts are potential biomarkers for early GFR decline in T1DM and MA. Measurement of these analytes could provide the basis for identifying patients at risk of early decline in renal function to target and intensify renoprotective treatment

Gain-of-function IKBKB mutation causes human combined immune deficiency

Genetic mutations account for many devastating early onset immune deficiencies. In contrast, less severe and later onset immune diseases, including in patients with no prior family history, remain poorly understood. Whole exome sequencing in two cohorts of such patients identified a novel heterozygous de novo IKBKB missense mutation (c.607G>A) in two separate kindreds in whom probands presented with immune dysregulation, combined T and B cell deficiency, inflammation, and epithelial defects. IKBKB encodes IKK2, which activates NF-κB signaling. IKK2V203I results in enhanced NF-κB signaling, as well as T and B cell functional defects. IKK2V203 is a highly conserved residue, and to prove causation, we generated an accurate mouse model by introducing the precise orthologous codon change in Ikbkb using CRISPR/Cas9. Mice and humans carrying this missense mutation exhibit remarkably similar cellular and biochemical phenotypes. Accurate mouse models engineered by CRISPR/Cas9 can help characterize novel syndromes arising from de novo germline mutations and yield insight into pathogenesis

Correlates of Circulating 25-Hydroxyvitamin D: Cohort Consortium Vitamin D Pooling Project of Rarer Cancers

Low vitamin D status is common globally and is associated with multiple disease outcomes. Understanding the correlates of vitamin D status will help guide clinical practice, research, and interpretation of studies. Correlates of circulating 25-hydroxyvitamin D (25(OH)D) concentrations measured in a single laboratory were examined in 4,723 cancer-free men and women from 10 cohorts participating in the Cohort Consortium Vitamin D Pooling Project of Rarer Cancers, which covers a worldwide geographic area. Demographic and lifestyle characteristics were examined in relation to 25(OH)D using stepwise linear regression and polytomous logistic regression. The prevalence of 25(OH)D concentrations less than 25 nmol/L ranged from 3% to 36% across cohorts, and the prevalence of 25(OH)D concentrations less than 50 nmol/L ranged from 29% to 82%. Seasonal differences in circulating 25(OH)D were most marked among whites from northern latitudes. Statistically significant positive correlates of 25(OH)D included male sex, summer blood draw, vigorous physical activity, vitamin D intake, fish intake, multivitamin use, and calcium supplement use. Significant inverse correlates were body mass index, winter and spring blood draw, history of diabetes, sedentary behavior, smoking, and black race/ethnicity. Correlates varied somewhat within season, race/ethnicity, and sex. These findings help identify persons at risk for low vitamin D status for both clinical and research purposes

Ikbkb Gain-of-Function in human disease

The NFkB signaling pathway is important in regulating numerous immune and inflammatory responses. NFkB family members can modulate the transcription of cytokines, as well as regulate genes involved in cellular differentiation, survival, proliferation, and immune cell function. Multiple groups have identified hypomorphic mutations in IKBKB (encodes IKKB) in patients suffering from immunodeficiency, where impaired NFkB activity was observed. My PhD has focused on the effects of an IKKB gain-of-function mutation and its role in human disease. In this thesis I describe experiments conducted to investigate the effects of a novel heterozygous de novo missense mutation that we identified in a proband with immunodeficiency. The mutation was found to result in a valine to isoleucine amino acid substitution within the kinase domain of the IKKB domain sequence, and resulted in a gain-of-function effect on IKKB. This enabled overactivation of the NFkB signaling pathway. To prove causation of this mutation, we generated a CRISPR-cas9 mouse model carrying the orthologous mutation. Biochemical and cellular analysis revealed similarities between the human and the mouse, therefore conferring a causative role of the mutation in the proband's immunodeficiency (Chapter 3). Through aging and observation of the mouse model, we identified the development of an inflammatory condition that involved the skin and bone/joints, and closely resembled the IL-17-mediated human disease, psoriatic arthritis (PsA) (Chapter 4). A gene dosage effect was evident where a skin-only disease was present in mice that were heterozygous for the IkbkbV203I variant, whilst a skin and systemic inflammatory illness developed when mice carry a double dose of the IkbkbV203I variant. The Ikbkb gain-of-function mutation generated a remarkable Treg population that abnormally produces increased IL-17 both in lymphoid tissues and at the sites of inflammation (Chapter 5). Single-cell RNA sequencing enabled the identification of an abnormally abundant Treg cluster within the spleen and bone marrow of mice homozygous for the IkbkbV203I. This cluster resembled a gene signature similar to an established non-lymphoid tissue Treg population, as well as a strong NFkB signature mediated by the gain-of-function mutation (Chapter 6). In this thesis I have investigated and identified the effects of an overactive IKKB protein within the immune system to result in primary immunodeficiency disease (PID) and the IL-17-mediated inflammatory condition, psoriatic arthritis in a mouse model. Our findings provide evidence that a fine balance of the NFkB is required to maintain immune system homeostasis. Furthermore, we have identified a biomarker for progression from skin-only inflammation to psoriatic arthritis through the presence of IL-17+ Tregs, mediated by GoF IKKB. We expect that these findings will be important in better defining diagnosis methods, as well as novel therapeutic targets for PIDs and PsA

Surveillance for Health Behaviors of American Indians and Alaska Natives—Findings From the Behavioral Risk Factor Surveillance System, 2000–2006

BACKGROUND. The authors compared estimates for cancer risk factors, use of cancer screening tests, health status indicators, and access to care for American Indians and Alaska Natives (AI/ANs) and non-Hispanic whites (NHWs) in the US and for AI/ANs in 6 Indian Health Service regions. METHODS. Behavioral Risk Factor Surveillance System data were aggregated from the years 2000 through 2006 and were used to calculate weighted prevalence estimates by gender for key variables except demographic variables. RESULTS. Compared with NHWs, AI/ANs had lower prevalence estimates for income, educational attainment, insurance coverage, and access to personal healthcare providers. AI/ANs in Alaska and NHWs had similar estimates for diabetes (approximately 6%); however, the prevalence was nearly twice as high among AI/ANs in the other regions. The prevalence of obesity was higher for AI/ ANs (29.6%) than for NHWs (20.9%). The prevalence of binge drinking was higher among AI/AN males (24.9%) than among AI/AN females (8.5%). Heavy drinking was more prevalent among NHW females (5.3%) than among AI/AN females (3.5%). AI/ANs were more likely to be current smokers (31.1%) than NHWs (22.8%). The prevalence of AI/ANs who never smoked ranged from 31.5% in Alaska to 56.9% in the Southwest. In 5 of the 6 regions, AI/AN females had lower prevalence estimates of both Papanicolaou and mammography testing than NHW females. The use of colorectal cancer screening tests was more common among NHWs (53.8%) than among AI/ANs (44%). CONCLUSIONS. Although cancer health disparities persist among AI/ANs, the current analysis indicated that variation in the prevalence of their chronic disease risk factors may be obscured when national data are not examined by smaller geographic areas such as regions

Colorectal Cancer in U.S. Adults Younger than 50 Years of Age, 1998--2001

BACKGROUND. Colorectal cancer (CRC) incidence rates are increasing among persons younger than 50 years of age, a population routinely not screened unless an individual has a high risk of CRC. This population-based study focuses primarily on describing the CRC burden for persons in this age group. METHODS. The data used for this study were derived from the National Program of Cancer Registries (NPCR) and Surveillance, Epidemiology, and End Results (SEER) surveillance systems. Age-adjusted incidence rates, rate ratios, and their corresponding 95% confidence intervals were calculated. RESULTS. CRC is ranked among the top 10 cancers occurring in males and females aged 20–49 years regardless of race. Persons younger than 50 years were more likely to present with less localized and more distant disease than do older adults. Among younger adults, age-adjusted incidence rates for poorly differentiated cancers were twice as high as rates for well-differentiated cancers. Incidence rates for poorly differentiated cancers were 60% higher than that for welldifferentiated cancers diagnosed in older adults. Rates were significantly higher for blacks and significantly lower for Asians/Pacific Islanders when compared with that for whites for the most demographic and tumor characteristics examined. CONCLUSIONS. This study confirms the findings of previous population-based studies suggesting that younger patients present with more advanced disease than do older patients. This study also identifies racial and ethnic disparities in CRC incidence in this population. These findings suggest the need for additional studies to understand the behavior and etiology of CRC in blacks

Using Population-based Cancer Registry Data to Assess the Burden of Human Papillomavirus-associated Cancers in the United States: Overview of Methods

Increased attention to human papillomavirus (HPV)-associated cancers in light of the recent release of an HPV vaccine, as well as increased availability of cancer registry data that now include reporting from a large proportion of the US population, prompted the current assessment of HPV-associated cancers. This article describes methods used to assess the burden of HPV-associated cervical, vulvar, vaginal, penile, anal, and oral cavity/oropharyngeal cancers in the United States during 1998 through 2003 using cancer registry data, and it provides a brief overview of the epidemiology of these cancers. Persistent infection with the human papillomavirus (HPV) is considered to be a cause of nearly all cervical cancer.1 It is believed that HPV also is associated with approximately 90% of anal cancers; 40% of penile, vaginal, and vulvar cancers; 25% of oral cavity cancers; and 35% of oropharyngeal cancers.2,3 A quadrivalent HPV vaccine that protects against HPV type 6 (HPV-6), HPV-11, HPV-16, and HPV-18 has been approved for use in the United States for females ages 9 years to 26 years, and a bivalent vaccine that protects against HPV-16 and HPV-18 currently is under review by the US Food and Drug Administration. It has been demonstrated that the HPV vaccine reduces the incidence of cervical, vaginal, and vulvar precancers, offering hope for the reduction in incidence of these diseases and the corresponding invasive cancers among women.4,5 Current studies are assessing the efficacy of the vaccine on HPV-associated disease in men.6 Close surveillance of these cancers will be necessary to ensure that high-risk populations are being reached by vaccination programs. Increased attention to HPV-associated cancers in light of the recent release of the vaccine, as well as increased availability of cancer registry data, prompted the current Supplement of Cancer titled ‘‘Assessing the Burden of HPV-Associated Cancers in the United States’’ (ABHACUS). The major purposes of this Supplement are to assess the current burden of anogenital and oropharyngeal cancers associated with HPV within the United States and to provide a baseline for monitoring future trends in HPV-associated cancers. This article describes methods used to assess the burden of HPV-associated cancers in the United States—methods that are common to several articles in the Supplement. This article describes the data sources, case definitions, variables, and analytic methods of descriptive epidemiologic articles that are included in this Supplement, and it provides an overall picture of the burden of HPV-associated cancers