How Good Is Online Information for Patients on the Treatment for Luminal Gastrointestinal Cancers? A Comprehensive Evaluation in English and Spanish

The internet has become a necessary communication platform for health information. The quality of online material for patients varies significantly, and this is not different for material on gastrointestinal cancers. We aimed to assess English and Spanish online patient information addressing esophageal, gastric, and colorectal cancer treatment. Six independent Google searches were conducted using the terms: esophageal cancer treatment, gastric cancer treatment, colorectal cancer treatment, and their translations in Spanish. Websites were included in the top 50 results for each search. Readability was assessed using two validated tests for each language. Understandability/actionability, quality, and cultural sensitivity were assessed using Patient Education Materials Assessment Tool (PEMAT), DISCERN, and Cultural Sensitivity Assessment Tool (CSAT), respectively. Pearson's chi-squared was used for categorical variables and Wilcoxon rank-sum (2 groups) or Kruskal-Wallis (> 2 groups) for continuous. One hundred twelve websites were analyzed. Readability levels were high in both languages (between 11th grade and university level) and significantly higher in English. Mean quality scores for English and Spanish were consistent with good quality. CSAT scores met the cultural acceptability with lower CSAT scores for gastric cancer treatment in English. Higher actionability scores were found in English for colorectal cancer. Also, there was a clear trend for higher cultural sensitivity and quality of Spanish material for gastric cancer treatment. Online patient information on esophageal, gastric, and colorectal cancer treatment, in English and Spanish, were at a readability level above the average literacy level and even significantly higher in English. Initiatives to improve online information on gastrointestinal cancer treatments are warranted.

Abstract A016: Successful design and execution of two gastric cancer chemoprevention trials in Central America and Puerto Rico

Gastric adenocarcinoma (GAC) is the third leading global cause of cancer mortality and leading infection-associated cancer. The high incidence regions are Latin America, East Asia, and Eastern Europe. In the U.S., GAC represents a major cancer disparity, double the incidence rates in all non-white populations, the opposite of Barrett’s Esophagus and EAC. Immigrants from high incidence regions maintain the risk profile of their nations of origin. In a paradigm shift, recent guidelines now recommend surveillance endoscopy (eg, 3 years) for patients with high-risk gastric premalignant conditions (GPMCs). Clinical trials of chemoprevention agents for patients with GPMCs are lacking. We conducted two independent, NCI DCP funded, phase II placebo-controlled chemoprevention trials in patients with GPMCs (intestinal metaplasia, atrophic gastritis). The oral agents were curcumin and eflornithine (DFMO). A highly bioavailable preparation of curcumin was used. The RCTs were conducted in Puerto Rico and rural Honduras, with important characteristics: (1) representative of Caribbean and Mesoamerican populations and linked to large U.S. immigrant populations; (2) high prevalence of H. pylori infection and GPMCs; (3) absence of turmeric and curcuminoids in the local diets; (4) proven bidirectional collaboration with academic institutions in the U.S. In the curcumin trial (NCT02782949) H. pylori negative patients were randomized to study drug or placebo for 6 months. In the eflornithine study (NCT02794428), H. pylori positive and negative subjects were randomized to study drug or placebo for 18 months, with endoscopy at baseline, and 6. 18, and 24 months. The primary outcomes were based upon changes in histologic parameters at 6 months. Principal study challenges included: (1) International and bilingual regulatory environment; (2) Strengthening of the research infrastructure, particularly in Central America; (3) Participant recruitment, eg, in the curcumin RCT in Honduras wherein only 10-15% are H. pylori negative; (4) The Covid-19 pandemic; (5) Natural disasters (3 hurricanes).

In Conclusion: Eflornithine and curcumin RCTs have been successfully completed, despite important challenges in implementation and execution. No losses to follow-up were encountered related to the pandemic or natural disasters. The south-south partnership may provide a model for chemoprevention and translational studies in Latino populations with prevalent cancers such as GAC.

Citation Format: Eleazar Montalvan-Sanchez, Maria Gonzalez-Pons, Dalton Norwood, Ricardo Dominguez, Keith Wilson, Marcia Cruz-Correa, Douglas Morgan. Successful design and execution of two gastric cancer chemoprevention trials in Central America and Puerto Rico [abstract]. In: Proceedings of the Second Biennial NCI Meeting: Translational Advances in Cancer Prevention Agent Development (TACPAD); 2022 Sep 7-9. Philadelphia (PA): AACR; Can Prev Res 2022;15(12 Suppl_2): Abstract nr A016.

Determination of Ochratoxin A in Currants, Raisins, Sultanas, Mixed Dried Fruit, and Dried Figs by Immunoaffinity Column Cleanup with Liquid Chromatography: Interlaboratory Study

An interlaboratory study was performed on behalf of the Food Standards Agency to evaluate the effectiveness of an affinity column cleanup liquid chromatographic (LC) method for the determination of ochratoxin A in a variety of dried fruit at European regulatory limits. To ensure homogeneity before analysis, laboratory samples are normally slurried with water in the ratio of 5 parts fruit to 4 parts water, and test materials in this form were used in the study. The test portion was extracted with acidified methanol. The extract was filtered, diluted with phosphate-buffered saline, and applied to an affinity column. The column was washed and ochratoxin A was eluted with methanol. Ochratoxin A was quantified by reversed-phase LC. The use of post-column pH shift to enhance the fluorescence of ochratoxin A by the addition of 1.1M ammonia solution to the column eluant is optional. Determination was by fluorescence. Currants, sultanas, raisins, figs, and mixed fruit (comprising dried pineapple, papaya, sultanas, prunes, dates, and banana chips), both naturally contaminated and blank (very low level), were sent to 24 collaborators in 7 European countries. Participants were asked to spike test portions of all test samples at a level equivalent to 5 ng/g ochra toxin A. Average recoveries ranged from 69 to 74%. Based on results for 5 naturally contaminated test samples (blind duplicates) the relative standard deviation for repeatability (RSDr) ranged from 4.9 to 8.7%, and the relative standard deviation for reproducibility (RSDR)rangedfrom14to28%. The method showed acceptable within-and be-tween-laboratory precision for all 5 matrixes, as evidenced by HORRAT values <1.3.

N-methyl D-aspartate receptor-mediated bidirectional control of extracellular signal-regulated kinase activity in cortical neuronal cultures

N-Methyl D-aspartate (NMDA) receptor activation of extracellular-signal regulated kinase (ERK) was examined in primary cortical cultures. Tetrodotoxin, NMDA receptor antagonists, or reduced extracellular calcium (0.1 mm) greatly decreased basal levels of phospho-ERK2, indicating that activity-dependent activation of NMDA receptors maintained a high level of basal ERK2 activation. This activity-dependent activation of phospho-ERK2 was blocked by pertussis toxin and inhibition of calcium/calmodulin-dependent kinase II and phosphatidylinositol 3-kinase but not by inhibition of protein kinase C or cAMP-dependent protein kinase. Addition of a calcium ionophore or 100 microm NMDA decreased phospho-ERK2 in the presence of 1 mm extracellular calcium but enhanced phospho-ERK2 in 0.1 mm extracellular calcium. The reduction in basal phospho-ERK2 by 100 microm NMDA was also reflected as a decrease in phospho-cAMP response element-binding protein. Inhibition of tyrosine phosphatases and serine/threonine phosphatases protein phosphatase 1 (PP1), PP2A, and PP2B did not prevent the inhibitory effect of NMDA. In the presence of tetrodotoxin, NMDA produced a bell-shaped dose-response curve with stimulation of phospho-ERK2 at 10, 25, and 50 microm NMDA and reduced stimulation at 100 microm NMDA. NMDA (50 microm) stimulation of phospho-ERK2 was completely blocked by pertussis toxin and inhibitors of phosphatidylinositol 3-kinase and was partially blocked by a calcium/calmodulin-dependent kinase II inhibitor. These results suggests that NMDA receptors can bidirectionally control ERK signaling.

Long-term telomere dynamics: modest increase of cell turnover in HIV-infected individuals followed for up to 14 years

To quantify the long-term dynamics of telomere lengths and the effect of HIV infection on lymphocyte turnover rates, we measured in a blinded study longitudinal samples from 6 individuals using a highly accurate method based on two-dimensional calibration of DNA sizes. For two uninfected controls followed 8 and 10 years the average telomeric terminal restriction fragment (TRF) shortening rate in peripheral blood mononuclear cells (PBMCs) was 50 and 60 bp/year, respectively, in agreement with previous measurements of cross-sectional samples. The TRF lengths of PBMCs from two slow progressors followed for 14 years declined by a rate of 120 +/-10 bp/year, i.e. 2-fold higher than the rate of TRF shortening for uninfected individuals. The rate of TRF shortening was higher in CD8 (140 +/-10 bp/year) than in CD4 (100 +/-10 bp/year) cells. The CD8 cell TRFs of the two fast progressors shortened faster (240 +/-10 bp/year) and the rate of CD4 cell TRF shortening in one of the fast progressors was 160 bp/year. These data suggest that HIV infection causes only a modest increase in the lymphocyte turnover which we speculate could be due to chronic activation of the immune system, and may not result in the exhaustion of its regenerative capacity and immunopathogenesis.

Inefficient formation of a complex among CXCR4, CD4 and gp120 in U937 clones resistant to X4 gp120-gp41-mediated fusion

Certain subclones (designated as minus clones) of the promonocytic U937 cell line do not support efficient infection and fusion mediated by T cell line adapted (TCLA) X4 HIV-1 gp120-gp41 (Env) although the CXCR4 and CD4 concentrations at their surfaces are similar to those at the surfaces of clones susceptible to HIV-1 entry (plus clones) (H. Moriuchi et al., J. Virol. 71, 9664-9671, 1997). To test the hypothesis that inefficient formation of gp120-CD4-CXCR4 complexes could contribute to the mechanism of resistance to Env-mediated fusion in the minus clones, we incubated plus and minus cells with HIV-1 LAI gp120 and coimmunoprecipitated CD4 by using anti-CXCR4 antibodies. The gp120 induced inefficient coimmunoprecipitation of CD4 in the minus clones but not in the plus ones. Overexpression of CD4 resulted in significant restoration of the minus clones' susceptibility to fusion in parallel with an increase in the amount of the gp120-CD4-CXCR4 complexes. These results not only suggest that the resistance to TCLA X4 HIV-1 entry in the U937 minus clones is due to the inability of these cells to efficiently form complexes among CD4, gp120, and CXCR4, but also provide a direct evidence for the correlation between fusion and the cell surface concentration of the complexes among CXCR4, CD4, and gp120. These data and similar recent observations in macrophages suggest that inefficient complex formation among CXCR4, CD4, and gp120 could be a general mechanism of cell resistance to gp120-gp41-mediated fusion and a major determinant of HIV-1 evolution in vivo.

A mechanism of resistance to HIV-1 entry: inefficient interactions of CXCR4 with CD4 and gp120 in macrophages

To test the hypothesis that inefficient interactions of CXCR4 with CD4 and gp120 could affect HIV-1 entry, we incubated macrophages, monocytes, and lymphocytes with gp120 and coimmunoprecipitated CD4 by using anti-CXCR4 antibodies. CD4 was efficiently coimmunoprecipitated in lymphocytes and monocytes but not in macrophages. Overexpression of CD4 in macrophages resulted in detection of CD4-CXCR4 and gp120-CD4-CXCR4 complexes in parallel with the restoration of macrophage fusion susceptibility. These results suggest a mechanism of resistance to entry of some X4 HIV-1 strains into macrophages and a method for dissection of the initial stages of HIV entry.

Telomere dynamics in monkeys: increased cell turnover in macaques infected with chimeric simian-human immunodeficiency viruses

To address the question of how cell turnover is affected by retroviral infections, we used the telomeric terminal restriction fragments (TRFs) as markers of cell replicative history and measured their length in macaques infected with chimeric simian-human immunodeficiency viruses (SHIVs). The TRF lengths of mononuclear cells in 104 samples, including longitudinal samples from nine cynomolgus and ten pig-tailed macaques infected with SHIV, and in samples from 26 uninfected macaques, were quantitated by an improved method, based on two-dimensional calibration of DNA sizes, pulsed field electrophoresis, and high-resolution Southern blot images. The average TRF lengths of peripheral blood mononuclear cells (PBMCs) from uninfected pig-tailed (14.9+/-1.6 kbp) and cynomolgus (14.1+/-1.8 kbp) macaques were about 3 and 5 kbp longer than those of human infants and 30-year-old adults, respectively. The rate of TRF length shortening in infected pig-tailed macaques was significantly (P = 0.035) higher (2.2-fold) than in uninfected monkeys. The TRFs in SHIV-infected cynomolgus monkeys, which, in general, had lower viral loads than pig-tailed macaques, shortened on average more rapidly (1.6-fold) than in uninfected animals, but the difference was not statistically significant. The TRFs of mononuclear cells from the lymph nodes of two rapidly progressing SHIV-infected macaques that developed AIDS and died also shortened in parallel but somewhat more rapidly than in the PBMCs. These results suggest that the rate of PBMC turnover in macaques could be increased several-fold during infections by immunodeficiency viruses, likely due to immune activation by SHIV antigens.

Chronic ethanol upregulates NMDA and AMPA, but not kainate receptor subunit proteins in rat primary cortical cultures

The present study examined the effects of chronic ethanol exposure on the expression of N-methyl-D-aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxalone (AMPA) and kainate receptor subunit proteins in rat cortical neuronal cultures grown in media containing 2 mM (high) or 0.1 mM (low) glutamine. Immunoblot analysis of NMDA (NR1, NR2A, NR2B, and NR2D), AMPA (GluR1 and GluR2/3), and kainate (GluR6/7) subunit polypeptides in 3-, 5-, 8-, 10-, and 12 day-old-cultures showed that NMDA receptor subunits NR1, NR2A, and NR2B and AMPA receptor subunits GluR2/3 progressively increased as a function of time, whereas levels of NMDA subunit NR2D were high at day 3 and progressively declined to barely detectable levels by day 12. Levels of AMPA subunit GluR1 and the kainate subunit GluR6/7 remained stable throughout the time course. Replacing the culture media with low glutamine media at culture day 5 did not alter the levels of subunit proteins measured at culture days 9 and 13. However, exposure of low glutamine cultures to 100 mM ethanol for 4 days (starting at culture day 9) significantly increased the levels of NMDA receptor subunits (NR1, NR2A, and NR2B) and AMPA receptor subunits (GluR1 and GluR2/3), but had no effect upon kainate receptor subunits (GluR6/7) or the synapse-associated proteins synapsin I and PSD-95. In contrast, chronic ethanol did not alter the levels of any of these subunit proteins in cells grown in high glutamine. These data demonstrate that under certain experimental conditions, prolonged exposure to ethanol upregulates NMDA and AMPA receptor subunit proteins, but has no effect upon kainate receptor subunit proteins. Because we have previously shown that acute ethanol can inhibit NMDA and AMPA, but not kainate, receptor function in these cultures, the increase in subunit expression likely reflects an adaptive response to the inhibitory effects of ethanol and suggests that both NMDA and AMPA receptors may play an important role in adaptation of the CNS to chronic ethanol.

Sensitive method for measuring telomere lengths by quantifying telomeric DNA content of whole cells

Recently, a new method for measuring telomere lengths based on telomere DNA content was developed. The method, which is based on the ratio of telomere to centromere DNA content (TC ratio), is highly sensitive, allowing the analysis of small quantities of DNA. However, the method required the isolation of DNA, which can be difficult or impossible for small numbers of cells. Here, we suggest an improvement of this method that can directly estimate telomere lengths from whole cells. We optimized the method for whole cells and purified DNA and found that accurate TC ratios can be obtained from as little as 9 ng of DNA or 800 whole cells. There was no statistically significant difference between the ratios obtained with purified DNA or with whole cells, indicating that the isolation of DNA is not necessary for small samples.

Telomere dynamics in HIV-1 infected and uninfected chimpanzees measured by an improved method based on high-resolution two-dimensional calibration of DNA sizes

We developed an improved method for accurately measuring telomere lengths based on two-dimensional calibration of DNA sizes combined with pulsed field electrophoresis and quantitative analysis of high-resolution gel images. This method was used to quantify the length of telomeres in longitudinal samples of peripheral blood mononuclear cells (PBMCs) from five chimpanzees infected with human immunodeficiency virus type 1 (HIV-1) and three uninfected animals, 14 to 27 years of age. The average length of the telomere restriction fragments (TRF) of infected and uninfected chimpanzees were 11.7 +/- 0.25 kbp, and 11.6 +/- 0.61 kbp, respectively, and were about 1 kbp and 3 kbp longer than those of human infants and 30 year old adults, respectively. There was a trend of a slight decrease (30-60 bp per year) in the TRF of two HIV infected chimpanzees over 30-35 months, while the TRF of one naive chimpanzee slightly increased over 20 months. Although the number of chimpanzees in this study is small and no statistically significant linear dependencies on time were observed, it appears that in chimpanzees, rates of shortening of the TRF are comparable or smaller than in adult humans and are not significantly affected by HIV-1 infection, which may be related to the inability of HIV-1 to cause disease in these animals.

Chronic ethanol increases N-methyl-D-aspartate-stimulated nitric oxide formation but not receptor density in cultured cortical neurons

The effects of prolonged ethanol exposure on excitatory amino acid receptor stimulated nitric oxide (NO) formation were examined in primary rat cortical neuronal cultures. Chronic ethanol (4 days, 100 mM) potentiated N-methyl-D-aspartate (NMDA)-stimulated NO formation as determined by measuring the conversion of [3H]arginine to [3H]citrulline. In contrast, chronic ethanol had no effect on NO formation stimulated by kainate, alpha-amino-3-hydroxy-5-methyl-4-isoxalonepropionic acid, or the calcium ionophore ionomycin. Potassium chloride-stimulated NO formation was also enhanced by chronic ethanol treatment, but this effect was not seen in the presence of the ionotropic glutamate receptor antagonists MK-801 and 6-cyano-7-nitroquinoxaline-2,3-dione. Immunoblot analysis of expression of NR1, NR2A, and NR2B receptor subunits showed no difference between control and chronic ethanol-treated cultures. In support of this apparent lack of change in receptor density, there was no difference in the specific binding of 125I-MK-801 between control and chronic ethanol-treated groups. These results demonstrate that prolonged ethanol exposure selectively enhanced NMDA receptor-stimulated NO formation, which may play an important role in alcohol dependence, withdrawal, and alcohol-associated brain damage. These results also suggest that chronic ethanol-induced increases in NMDA receptor function may not be due to a simple increase in the number of NMDA receptors or change in NMDA receptor subunit composition but may instead reflect more complicated and subtle changes.