Integrin α6 mediates the drug resistance of acute lymphoblastic B-cell leukemia.

Resistance to multimodal chemotherapy continues to limit the prognosis of acute lymphoblastic leukemia (ALL). This occurs in part through a process called adhesion-mediated drug resistance, which depends on ALL cell adhesion to the stroma through adhesion molecules, including integrins. Integrin α6 has been implicated in minimal residual disease in ALL and in the migration of ALL cells to the central nervous system. However, it has not been evaluated in the context of chemotherapeutic resistance. Here, we show that the anti-human α6-blocking Ab P5G10 induces apoptosis in primary ALL cells in vitro and sensitizes primary ALL cells to chemotherapy or tyrosine kinase inhibition in vitro and in vivo. We further analyzed the underlying mechanism of α6-associated apoptosis using a conditional knockout model of α6 in murine BCR-ABL1+ B-cell ALL cells and showed that α6-deficient ALL cells underwent apoptosis. In vivo deletion of α6 in combination with tyrosine kinase inhibitor (TKI) treatment was more effective in eradicating ALL than treatment with a TKI (nilotinib) alone. Proteomic analysis revealed that α6 deletion in murine ALL was associated with changes in Src signaling, including the upregulation of phosphorylated Lyn (pTyr507) and Fyn (pTyr530). Thus, our data support α6 as a novel therapeutic target for ALL.

Iodine status of adults in Taiwan 2005-2008, 5 years after the cessation of mandatory salt iodization.

BACKGROUND/PURPOSE: Iodine deficiency causes a broad spectrum of disorders across all ages. Mandatory salt iodization in Taiwan successfully reduced the goiter rate from 21.6% to 4.3% in schoolchildren surveyed in 1971. The program continued until 2003 when salt iodization was changed from mandatory to voluntary. The purpose of this study was to investigate the iodine status of Taiwanese individuals after the change in the iodine policy. METHODS: Urinary iodine (UI) was measured in samples from adults in the Nutrition and Health Survey in Taiwan 2005-2008. RESULTS: The median UI level was 100 µg/L, and the percentage of populations with UI levels below 100 µg/L and 50 µg/L was 50.1% and 15.1%, respectively, indicating that the iodine status was borderline adequate. Men had a higher UI level than women (102 µg/L vs. 98 µg/L, p = 0.003), and older individuals (age > 60 years) had a lower UI level than younger people, particularly in women. The iodine status of the population < 50 years was sufficient, but it was insufficient in older groups. Mild iodine insufficiency was noted in all areas of Taiwan except the Southern area and Penghu islands, with the lowest UI level of 79 µg/L in the Mountain area. Although the UI level of women of childbearing age (19-44 years) was 103 µg/L, there may be a risk of iodine deficiency during pregnancy. CONCLUSION: The iodine nutrition of the Taiwanese population in 2005-2008 was borderline adequate, with insufficiency in some subgroups. Further monitoring of the iodine status is necessary.

Integrin alpha4 blockade sensitizes drug resistant pre-B acute lymphoblastic leukemia to chemotherapy.

Bone marrow (BM) provides chemoprotection for acute lymphoblastic leukemia (ALL) cells, contributing to lack of efficacy of current therapies. Integrin alpha4 (alpha4) mediates stromal adhesion of normal and malignant B-cell precursors, and according to gene expression analyses from 207 children with minimal residual disease, is highly associated with poorest outcome. We tested whether interference with alpha4-mediated stromal adhesion might be a new ALL treatment. Two models of leukemia were used, one genetic (conditional alpha4 ablation of BCR-ABL1 [p210(+)] leukemia) and one pharmacological (anti-functional alpha4 antibody treatment of primary ALL). Conditional deletion of alpha4 sensitized leukemia cell to nilotinib. Adhesion of primary pre-B ALL cells was alpha4-dependent; alpha4 blockade sensitized primary ALL cells toward chemotherapy. Chemotherapy combined with Natalizumab prolonged survival of NOD/SCID recipients of primary ALL, suggesting adjuvant alpha4 inhibition as a novel strategy for pre-B ALL.

Targeting survivin overcomes drug resistance in acute lymphoblastic leukemia.

Relapse of drug-resistant acute lymphoblastic leukemia (ALL) has been associated with increased expression of survivin/BIRC5, an inhibitor of apoptosis protein, suggesting a survival advantage for ALL cells. In the present study, we report that inhibition of survivin in patient-derived ALL can eradicate leukemia. Targeting survivin with shRNA in combination with chemotherapy resulted in no detectable minimal residual disease in a xenograft model of primary ALL. Similarly, pharmacologic knock-down of survivin using EZN-3042, a novel locked nucleic acid antisense oligonucleotide, in combination with chemotherapy eliminated drug-resistant ALL cells. These findings show the importance of survivin expression in drug resistance and demonstrate that survivin inhibition may represent a powerful approach to overcoming drug resistance and preventing relapse in patients with ALL.

Iodine Status of Taiwanese Population in 2013: 10 Years After Changing From Mandatory to Voluntary Salt Iodization.

BACKGROUND: In 2003, Taiwan's iodine policy changed from mandatory to voluntary. The Nutrition and Health Survey in Taiwan (NAHSIT) 2001-2002 for schoolchildren showed adequate iodine nutrition, while NAHSIT 2005-2008 for adults showed the iodine status was at borderline adequacy. OBJECTIVE: To investigate the iodine status of the Taiwanese population from schoolchildren to adulthood 10 years after the change of the salt iodization policy. METHOD: Urinary iodine was measured in samples from subjects in NAHSIT 2013. RESULTS: The median urinary iodine concentration (UIC) of the Taiwanese population aged 6 years and above in 2013 was 96 µg/L, indicating mild iodine deficiency. The median UIC of 6- to 12-year-old schoolchildren was 124 µg/L (interquartile range [IQR]: 92-213 µg/L), and 115 µg/L (IQR: 80-166 µg/L), 125 µg/L (IQR: 74-161 µg/L), 73 µg/L (IQR: 52-131 µg/L), and 78 µg/L (IQR: 52-132 µg/L) in populations aged 13 to 18 years, 19 to 44 years, 45 to 64 years, and ≥65 years, respectively. Declining iodine nutrition in age groups ≥45 years old was noted that the median UIC of populations aged 45 to 64 years and ≥65 years was 99 and 88 µg/L, respectively, in NAHSIT 2005-2008. The median UIC of schoolchildren was not lower than that during the mandatory salt fortification period, but the distribution of urinary iodine levels signified a dietary pattern change. CONCLUSION: Wide-ranging variation in iodine nutrition levels was observed in different age groups. Universal salt iodization, as suggested by the World Health Organization, should be the best strategy to achieve adequate iodine nutrition.

Characterization of FcγRIIIA effector cells used in in vitro ADCC bioassay: Comparison of primary NK cells with engineered NK-92 and Jurkat T cells.

Antibody-dependent cell-mediated cytotoxicity (ADCC) is an important mechanism of action (MOA) of several therapeutic antibody drugs and evaluation in ADCC bioassays is important in antibody drug development and maintenance. Three types of effector cells now routinely used in bioassay evaluation of ADCC are natural killer cells from human donors (FcγRIIIA+primary NK), FcγRIIIA engineered NK-92 cells and FcγRIIIA/NFAT-RE/luc2 engineered Jurkat T cells. Engineered effector cells were developed to address need for improved precision and accuracy of classic NK cell ADCC bioassays. The main purpose of our study was to rationalize which of these ADCC effector cells best simulate the expected response in human subjects and to identify which effector cells and assays best fit ADCC bioassay needs during antibody drug development. We characterized differences between the effector cells and compared ADCC biological activities using the well-known humanized IgG1 antibody drug, trastuzumab. The three effector cell types studied expressed either V-158 or F-158 allotype of FcγRIIIA, hence six cell preparations were compared. Our results demonstrate highest surface expression of FcγRIIIA in primary NK and engineered NK-92 (V-158) cells with nearly all expressed on the cell surface. In contrast, expression in engineered Jurkat T cells was low with only a small percentage expressed on the cell surface. Studies evaluating binding of trastuzumab to effector cells demonstrated the highest affinity of FcγRIIIA in primary NK and NK-92 (V-158) cells. ADCC cytotoxicity studies showed greatest trastuzumab potency in primary NK and engineered NK-92 (V-158) cells and negligible cell lysis obtained using engineered Jurkat T cells. In contrast, the engineered Jurkat T (V-158) cells responded as effectively as primary NK (V/V) cells to nuclear factor of activated T cells (NFAT2) activation upon binding of trastuzumab to FcγRIIIA, demonstrating similar ADCC pathway activation in these cells despite the low surface expression of FcγRIIIA and its low affinity for trastuzumab. Dose-response range of trastuzumab in activation of NFAT2 (measured as pNFAT2 dephosphorylation) was very similar to response in classic ADCC assay for primary and NK-92 cells and to response in ADCC reporter assay for Jurkat T effector cells, bridging the assays. Trastuzumab potency in ADCC reporter assay using the engineered Jurkat T cells was close to that seen using either primary NK or engineered NK-92 cells in classic ADCC assay. In summary, all three effector cell systems differentially express FcγRIIIA and provide dose-dependent ADCC pathway activity, yet only primary NK and engineered NK-92 cells are capable of inducing ADCC-mediated cell lysis. Engineered Jurkat T effector cells have value to assure antibody manufacturing consistency and in other applications where accuracy and precision are important. For functional assessment of ADCC activity, primary NK or NK-92 (V-158) cells better reflect the physiologically relevant ADCC mechanism of action. As an engineered cell line, NK-92 cells may behave more reproducibly than primary NK, but this must be balanced with the objective for biological relevance in decisions on which NK cells to use in assay.

Dietary Pattern Associated with Frailty: Results from Nutrition and Health Survey in Taiwan.

OBJECTIVES: To investigate whether dietary patterns are associated with frailty phenotypes in an elderly Taiwanese population. DESIGN: Cross-sectional. SETTING: Nutrition and Health Survey in Taiwan (NAHSIT), 2014-2016. PARTICIPANTS: Noninstitutionalized Taiwanese nationals aged 65 years and older enrolled in the NAHSIT (N = 923). MEASUREMENTS: Dietary intake was assessed using a 79-item food-frequency questionnaire (FFQ). Presence of 5 frailty phenotypes was determined using modified Fried criteria and are summed into a frailty score. Using data from the NAHSIT (2014-15), reduced rank regression was used to find a dietary pattern that explained maximal degree of variation of the frailty scores. Logistic regression models were used to estimate the association between frailty and dietary pattern. The findings were validated with data from 2016. RESULTS: The derived dietary pattern was characterized with a high consumption of fruit, nuts and seeds, tea, vegetables, whole grains, shellfish, milk, and fish. The prevalence of frailty was 7.8% and of prefrailty was 50.8%, defined using the modified Fried criteria. Using data from the NAHSIT (2014-15), the dietary pattern score showed an inverse dose-response relationship with prevalence of frailty and pre-frailty. Individuals in the second dietary pattern tertile were one-third as likely to be frail as those in the first tertile (adjusted odds ratio (aOR) = 0.32, 95% confidence interval (CI) = 0.12-0.85), and those in the third tertile were 4% as likely to be frail as those in the first tertile (aOR = 0.04, 95% CI = 0.01-0.18). The dietary pattern score estimated using FFQ data from the NAHSIT 2016 was also significantly and inversely associated with frailty. CONCLUSION: Individuals with a dietary pattern with more phytonutrient-rich plant foods, tea, omega-3-rich deep-sea fish, and other protein-rich foods such as shellfish and milk had a reduced prevalence of frailty. Further research is necessary to confirm these findings and investigate whether related dietary interventions can reduce frailty in older adults.

Iodine status of Taiwanese children before the change in national salt iodization policy: a retrospective study of the nutrition and health survey in Taiwan 2001-2002.

Taiwan was an iodine deficiency area and endemic goiter was common in 1940's. Mandatory salt iodization started in 1967, and a 1971 survey indicated that goiter rates in children decreased from 21.6% to 4.3%. To understand iodine status before the change of national salt iodization program in 2003, from mandatory to voluntary salt iodization, we retrospectively measured urinary iodine concentrations of samples collected from children in the Nutrition and Health Survey in Taiwan 2001-2002. The median UI level for children aged 6-12 years was 123 µg/L (no differences between males and females). Females aged 10-12 years had the lowest urinary iodine levels. The percentages of this population with urinary iodine levels below 100, 50, and 20 µg/L were 35.2% ± 1.0%, 4.4% ± 0.4%, and 0.2% ± 0.1%, respectively. Older children were more likely to have low urinary iodine levels. People living in different areas of Taiwan had a median urinary iodine levels ranged from 113 µg/L to 164 µg/L (males: 113-153 µg/L; females: 105-174 µg/L), with the highest level in Penghu islands, and the lowest level in the eastern and southern (Southern area 2) areas. According to international criteria, iodine status in 2001-2002 was adequate, comparable to the surveyed goiter rates (4.3%, classified as iodine sufficiency) in 1971, inferring that iodine nutrition remained adequate and stable during this period. The present study is of great importance in documenting the iodine status of Taiwan before the change from mandatory to voluntary salt iodization to serve as a baseline data for future trend analysis in iodine nutrition.

SIRT1 activation by a c-MYC oncogenic network promotes the maintenance and drug resistance of human FLT3-ITD acute myeloid leukemia stem cells.

The FLT3-ITD mutation is frequently observed in acute myeloid leukemia (AML) and is associated with poor prognosis. In such patients, FLT3 tyrosine kinase inhibitors (TKIs) are only partially effective and do not eliminate the leukemia stem cells (LSCs) that are assumed to be the source of treatment failure. Here, we show that the NAD-dependent SIRT1 deacetylase is selectively overexpressed in primary human FLT3-ITD AML LSCs. This SIRT1 overexpression is related to enhanced expression of the USP22 deubiquitinase induced by c-MYC, leading to reduced SIRT1 ubiquitination and enhanced stability. Inhibition of SIRT1 expression or activity reduced the growth of FLT3-ITD AML LSCs and significantly enhanced TKI-mediated killing of the cells. Therefore, these results identify a c-MYC-related network that enhances SIRT1 protein expression in human FLT3-ITD AML LSCs and contributes to their maintenance. Inhibition of this oncogenic network could be an attractive approach for targeting FLT3-ITD AML LSCs to improve treatment outcomes.

Activation of adipose tissue macrophages in obese mice does not require lymphocytes.

OBJECTIVE: Macrophages which infiltrate adipose tissue and secrete proinflammatory cytokines may be responsible for obesity-induced insulin resistance. However, the reason why macrophages migrate into adipose tissue and become activated remains unknown though some studies suggest that this may be regulated by T and B lymphocytes. In this study, it has been tested whether T and B lymphocytes and natural killer (NK) cells were necessary for the obesity-induced activation of macrophages in adipose tissue. DESIGN AND METHODS: NOD/SCID/IL2-receptor gamma-chain knockout (NSG) mice, which lack mature T and B lymphocytes and NK cells, were made obese by selectively reducing litters and weaning onto a high-fat diet. Mice were then maintained on the diet for 10-11 weeks. RESULTS: Adipose tissue from obese NSG mice had more activated macrophages than nonobese mice. These macrophages were found in "crown-like structures" surrounding adipocytes, and expressed higher levels of the inflammatory cytokine TNF-α. However, obesity did not impair glucose tolerance in the NSG mice. CONCLUSIONS: These studies demonstrated that T and B lymphocytes and NK cells are not necessary for adipose tissue macrophage activation in obese mice. T and B lymphocytes and/or NK cells may be necessary for the development of obesity-induced impaired glucose tolerance.

Trends in hyperuricemia and gout prevalence: Nutrition and Health Survey in Taiwan from 1993-1996 to 2005-2008.

Hyperuricemia is a recognized risk factor for cardiovascular disease. This study investigated trends in uric acid levels, hyperuricemia and gout among adults in Taiwan from 1993-1996 to 2005-2008, using data collection from, Nutrition and health surveys in Taiwan (NAHSIT) conducted in 1993-1996 and 2005-2008. Information on food frequency, medical history, physical measures and fasting blood parameters were analyzed. Mean uric acid levels decreased between 1993-1996 and 2005-2008 in both genders (6.77 vs 6.59 mg/dL in men and 5.33 vs 4.97 mg/dL in women) and the prevalence of hyperuricemia declined from 25.3% to 22.0% in men (p<0.0001) and from 16.7% to 9.7% in women (p<0.0001). However, the prevalence of gout (self-reported) increased (4.74% vs 8.21% in men and 2.19% vs 2.33% in women, p<0.0001). Reduced rank regression was used to identify dietary patterns that explained significant amounts of variance in uric acid. Frequency of consumption of lean meat, soy products and soymilk, milk, eggs, vegetables, carrots, mushrooms, fruit and coffee were negatively associated with hyperuricemia, whereas consumption of organ meats, bamboo shoots, and soft drinks were positively associated with hyperuricemia. The dietary factor score (DFS) composed of the frequency of above food items decreased from -5.40 to -6.00 between the two surveys (p<0.0001). In conclusion, uric acid levels and prevalence of hyperuricemia both declined, whilst self-reported gout increased between 1993-1996 and 2005-2008. Changes in dietary patterns may in part explain the decrease in uric acid levels between the two national surveys.

Design and sample characteristics of the 2005-2008 Nutrition and Health Survey in Taiwan.

The Nutrition and Health Survey in Taiwan (NAHSIT) 2005-2008 was funded by the Department of Health to provide continued assessment of health and nutrition of the people in Taiwan. This household survey collected data from children aged less than 6 years and adults aged 19 years and above, and adopted a three-stage stratified, clustered sampling scheme similar to that used in the NAHSIT 1993-1996. Four samples were produced. One sample with five geographical strata was selected for inference to the whole of Taiwan, while the other three samples, including Hakka, Penghu and mountainous areas were produced for inference to each cultural stratum. A total of 6,189 household interviews and 3,670 health examinations were completed. Interview data included household information, socio-demographics, 24-hour dietary recall, food frequency and habits, dietary and nutritional knowledge, attitudes and behaviors, physical activity, medical history and bone health. Health exam data included anthropometry, blood pressure, physical fitness, bone density, as well as blood and urine collection. Response rate for the household interview was 65%. Of these household interviews, 59% participated in the health exam. Only in a few age subgroups were there significant differences in sex, age, education, or ethnicity distribution between respondents and non-respondents. For the health exam, certain significant differences between participants and non-participants were mostly observed in those aged 19-64 years. The results of this survey will be of benefit to researchers, policy makers and the public to understand and improve the nutrition and health status of pre-school children and adults in Taiwan.

Diet and health trends in Taiwan: comparison of two nutrition and health surveys from 1993-1996 and 2005-2008.

The availability of new food choices has increased dramatically in recent times, whilst increasingly sedentary lifestyles have reduced calorie intake requirements. The present study uses 24 hour dietary recall data, and biochemical and anthropometric measurements from the 1993-1996 and 2005-2008 Nutrition and Health Surveys in Taiwan (NAHSIT) to investigate trends in dietary habits, and cardiovascular and metabolic disease markers in Taiwanese persons aged 19 years and above. We found that dietary habits in Taiwan are changing, particularly in regards to intakes of cakes and sweets, and sugary drinks. Energy intakes in young people have increased, and combined with an increasingly sedentary lifestyle, this may have led to the increase in obesity and associated metabolic diseases. Large increases in the prevalence of the metabolic syndrome, diabetes, hypertriglyceridemia and gout have been observed. Fortunately, some positive dietary and behavioral changes have also been observed; including an increased avoidance of products made from animal fats and oils' and a concomitant increase in the use of vegetable oil. Intakes of fruit and vegetables, soy products, fish, whole grains, nuts and seeds have also increased; and intakes of red meat, carbohydrates and sodium containing foods have decreased. These positive dietary changes could explain the lack of large changes in the prevalence of hypertension and hypercholesterolemia, and the decrease in prevalence of hyperuricemia. Intake of dairy products remains low, and continues to be an important dietary issue in Taiwan.

Tubacin suppresses proliferation and induces apoptosis of acute lymphoblastic leukemia cells.

Over the past decade, histone deacetylase inhibitors have increasingly been used to treat various malignancies. Tubacin (tubulin acetylation inducer) is a small molecule that inhibits histone deacetylase 6 (HDAC6) and induces acetylation of α-tubulin. We observed a higher antiproliferative effect of tubacin in acute lymphoblastic leukemia (ALL) cells than in normal hematopoietic cells. Treatment with tubacin led to the induction of apoptotic pathways in both pre-B and T cell ALL cells at a 50% inhibitory concentration (IC(50)) of low micromolar concentrations. Acetylation of α-tubulin increases within the first 30 min following treatment of ALL cells with tubacin. We also observed an accumulation of polyubiquitinated proteins and poly(ADP-ribose) polymerase (PARP) cleavage. Furthermore, the signaling pathways activated by tubacin appear to be distinct from those observed in multiple myeloma. In this article, we demonstrate that tubacin enhances the effects of chemotherapy to treat primary ALL cells in vitro and in vivo. These results suggest that targeting HDAC6 alone or in combination with chemotherapy could provide a novel approach to treat ALL.

Integrated microfluidic and imaging platform for a kinase activity radioassay to analyze minute patient cancer samples.

Oncogenic kinase activity and the resulting aberrant growth and survival signaling are a common driving force of cancer. Accordingly, many successful molecularly targeted anticancer therapeutics are directed at inhibiting kinase activity. To assess kinase activity in minute patient samples, we have developed an immunocapture-based in vitro kinase assay on an integrated polydimethylsiloxane microfluidics platform that can reproducibly measure kinase activity from as few as 3,000 cells. For this platform, we adopted the standard radiometric (32)P-ATP-labeled phosphate transfer assay. Implementation on a microfluidic device required us to develop methods for repeated trapping and mixing of solid-phase affinity microbeads. We also developed a solid-state beta-particle camera imbedded directly below the microfluidic device for real-time quantitative detection of the signal from this and other microfluidic radiobioassays. We show that the resulting integrated device can measure ABL kinase activity from BCR-ABL-positive leukemia patient samples. The low sample input requirement of the device creates new potential for direct kinase activity experimentation and diagnostics on patient blood, bone marrow, and needle biopsy samples.

Gender-specific roles and needs in food-health security.

People rely on foods to provide energy and nutrients to sustain life and to ensure health. In the entire chain from acquiring foods to ingesting them, women contribute in unique ways to the food system. Although foods or nutrients requirements for both sexes are biologically similar in many aspects, women go through more complex life-cycles than men and may experience greater risk of nutrient deprivation due to their role to bear and to rear off-spring. Therefore, women and their offspring are particularly vulnerable to food scarcity and to poor dietary quality. On the other hand, the female genome, partly through sex hormones delays the development of many chronic diseases which result from the modern affluent lifestyle. The inherent biological roles of men and women and their socially constructed roles may interact with one another, affecting the health security of each gender, their families, and the well-being of the societies in which they live. Historically and contemporarily, women in general are socially and politically more underprivileged than men. The inequality which women have faced has jeopardized not only their health and that of their female children, but the well-being of all. In developed countries and in more and more developing countries, equal opportunities for education are promoted. Recent research indicates that women have a greater tendency than men to engage in healthy behaviours when empowered with health knowledge. Risky health-related behaviours, including poor food choices, are more often practiced by men and warrant more public health attention.