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Fulltext The Microenvironment in Epstein-Barr Virus-Associated Malignancies

Tan GW, Visser L, Tan LP, van den Berg A, Diepstra A

Pathogens, 2018 04 13;7(2).
PMID: 29652813 DOI: 10.3390/pathogens7020040

The Epstein–Barr virus (EBV) can cause a wide variety of cancers upon infection of different cell types and induces a highly variable composition of the tumor microenvironment (TME). This TME consists of both innate and adaptive immune cells and is not merely an aspecific reaction to the tumor cells. In fact, latent EBV-infected tumor cells utilize several specific mechanisms to form and shape the TME to their own benefit. These mechanisms have been studied largely in the context of EBV+ Hodgkin lymphoma, undifferentiated nasopharyngeal carcinoma, and EBV+ gastric cancer. This review describes the composition, immune escape mechanisms, and tumor cell promoting properties of the TME in these three malignancies. Mechanisms of susceptibility which regularly involve genes related to immune system function are also discussed, as only a small proportion of EBV-infected individuals develops an EBV-associated malignancy.
Partially hydrolyzed formula in non-exclusively breastfed infants: A systematic review and expert consensus

Vandenplas Y, Latiff AHA, Fleischer DM, Gutiérrez-Castrellón P, Miqdady MS, Smith PK, et al.

Nutrition, 2019 01;57:268-274.
PMID: 30223233 DOI: 10.1016/j.nut.2018.05.018

OBJECTIVES: Guidance and evidence supporting routine use of partially hydrolyzed formula (pHF) versus intact cows' milk protein (CMP) formula are limited in non-exclusively breastfed infants. The aim of this review was to better clarify issues of routine use of pHF in non-exclusively breastfed infants who are not at risk for allergic disease by using a systematic review and Delphi Panel consensus.
METHODS: A systematic review and Delphi consensus panel (consisting of eight8 international pediatric allergists and gastroenterologists) was conducted to evaluate evidence supporting growth, tolerability, and effectiveness of pHF in non-exclusively breastfed infants.
RESULTS: None of the studies reviewed identified potential harm of pHF use compared with CMP in non-exclusively breastfed infants. There was an expert consensus that pHF use is likely as safe as intact CMP formula, given studies suggesting these have comparable nutritional parameters. No high-quality studies were identified evaluating the use of pHF to prevent allergic disease in non-exclusively breastfed infants who are not at risk for allergic disease (e.g., lacking a parental history of allergy). Limited data suggest that pHF use in non-exclusively breastfed infants may be associated with improved gastric emptying, decreased colic incidence, and other common functional gastrointestinal symptoms compared with CMP. However, because the data are of insufficient quality, the findings from these studies have to be taken with caution. No studies were identified that directly compared the different types of pHF, but there was an expert consensus that growth, allergenicity, tolerability, effectiveness, and clinical role among such pHF products may differ.
CONCLUSIONS: Limited data exist evaluating routine use of pHFs in non-exclusively breastfed infants, with no contraindications identified in the systematic review. An expert consensus considers pHFs for which data were available to be as safe as CMP formula as growth is normal. The preventive effect on allergy of pHF in infants who are not at risk for allergic disease has been poorly studied. Cost of pHF versus starter formula with intact protein differs from country to country. However, further studies in larger populations are needed to clinically confirm the benefits of routine use of pHF in non-exclusively breastfed infants. These studies should also address potential consumer preference bias.
Fulltext HLA Expression in Relation to HLA Type in Classic Hodgkin Lymphoma Patients

Tan GW, Jiang P, Nolte IM, Kushekhar K, Veenstra RN, Hepkema BG, et al.

Cancers (Basel), 2021 Nov 20;13(22).
PMID: 34830986 DOI: 10.3390/cancers13225833

Several human leukocyte antigen (HLA) alleles are strongly associated with susceptibility to classic Hodgkin lymphoma (cHL), also in subgroups stratified for presence of the Epstein-Barr virus (EBV). We tested the hypothesis that the pressure on cHL tumour cells to lose HLA expression is associated with HLA susceptibility alleles. A meta-analysis was carried out to identify consistent protective and risk HLA alleles in a combined cohort of 839 cHL patients from the Netherlands and the United Kingdom. Tumour cell HLA expression was studied in 338 cHL cases from these two cohorts and correlated to the presence of specific susceptibility HLA alleles. Carriers of the HLA-DRB1*07 protective allele frequently lost HLA class II expression in cHL overall. Patients carrying the HLA-DRB1*15/16 (DR2) risk allele retained HLA class II expression in EBV- cHL and patients with the HLA-B*37 risk allele retained HLA class I expression more frequently than non-carriers in EBV+ cHL. The other susceptibility alleles showed no significant differences in expression. Thus, HLA expression by tumour cells is associated with a subset of the protective and risk alleles. This strongly suggests that HLA associations in cHL are related to peptide binding capacities of specific HLA alleles.
Fulltext Detection of circulating tumor DNA in plasma of patients with primary CNS lymphoma by digital droplet PCR

Zhong Y, Tan GW, Bult J, Veltmaat N, Plattel W, Kluiver J, et al.

BMC Cancer, 2024 Apr 02;24(1):407.
PMID: 38566053 DOI: 10.1186/s12885-024-12191-z

BACKGROUND: Primary central nervous system lymphoma (PCNSL) are rare mature B-cell lymphoproliferative diseases characterized by a high incidence of MYD88 L265P and CD79B Y196 hotspot mutations. Diagnosis of PCNSL can be challenging. The aim of the study was to analyze the detection rate of the MYD88 L265P and CD79B Y196 mutation in cell free DNA (cfDNA) in plasma of patients with PCNSL.
METHODS: We analyzed by digital droplet PCR (ddPCR) to determine presence of the MYD88 L265P and CD79B Y196 hotspot mutations in cfDNA isolated from plasma of 24 PCNSL patients with active disease. Corresponding tumor samples were available for 14 cases. Based on the false positive rate observed in 8 healthy control samples, a stringent cut-off for the MYD88 L265P and CD79B Y196 mutation were set at 0.3% and 0.5%, respectively.
RESULTS: MYD88 L265P and CD79B Y196 mutations were detected in 9/14 (64%) and 2/13 (15%) tumor biopsies, respectively. In cfDNA samples, the MYD88 L265P mutation was detected in 3/24 (12.5%), while the CD79B Y196 mutation was not detected in any of the 23 tested cfDNA samples. Overall, MYD88 L265P and/or CD79B Y196 were detected in cfDNA in 3/24 cases (12.5%). The detection rate of the combined analysis did not improve the single detection rate for either MYD88 L265P or CD79B Y196.
CONCLUSION: The low detection rate of MYD88 L265P and CD79B Y196 mutations in cfDNA in the plasma of PCNSL patients argues against its use in routine diagnostics. However, detection of MYD88 L265P by ddPCR in cfDNA in the plasma could be considered in challenging cases.
Fulltext Skin color variation in Orang Asli tribes of Peninsular Malaysia

Ang KC, Ngu MS, Reid KP, Teh MS, Aida ZS, Koh DX, et al.

PLoS One, 2012;7(8):e42752.
PMID: 22912732 DOI: 10.1371/journal.pone.0042752

Pigmentation is a readily scorable and quantitative human phenotype, making it an excellent model for studying multifactorial traits and diseases. Convergent human evolution from the ancestral state, darker skin, towards lighter skin colors involved divergent genetic mechanisms in people of European vs. East Asian ancestry. It is striking that the European mechanisms result in a 10-20-fold increase in skin cancer susceptibility while the East Asian mechanisms do not. Towards the mapping of genes that contribute to East Asian pigmentation there is need for one or more populations that are admixed for ancestral and East Asian ancestry, but with minimal European contribution. This requirement is fulfilled by the Senoi, one of three indigenous tribes of Peninsular Malaysia collectively known as the Orang Asli. The Senoi are thought to be an admixture of the Negrito, an ancestral dark-skinned population representing the second of three Orang Asli tribes, and regional Mongoloid populations of Indo-China such as the Proto-Malay, the third Orang Asli tribe. We have calculated skin reflectance-based melanin indices in 492 Orang Asli, which ranged from 28 (lightest) to 75 (darkest); both extremes were represented in the Senoi. Population averages were 56 for Negrito, 42 for Proto-Malay, and 46 for Senoi. The derived allele frequencies for SLC24A5 and SLC45A2 in the Senoi were 0.04 and 0.02, respectively, consistent with greater South Asian than European admixture. Females and individuals with the A111T mutation had significantly lighter skin (p = 0.001 and 0.0039, respectively). Individuals with these derived alleles were found across the spectrum of skin color, indicating an overriding effect of strong skin lightening alleles of East Asian origin. These results suggest that the Senoi are suitable for mapping East Asian skin color genes.
Should Partial Hydrolysates Be Used as Starter Infant Formula? A Working Group Consensus

Vandenplas Y, Alarcon P, Fleischer D, Hernell O, Kolacek S, Laignelet H, et al.

J Pediatr Gastroenterol Nutr, 2016 Jan;62(1):22-35.
PMID: 26513620 DOI: 10.1097/MPG.0000000000001014

Partially hydrolyzed formulas (pHFs) are increasingly used worldwide, both in the prevention of atopic disease in at-risk infants and in the therapeutic management of infants with functional gastrointestinal manifestations. Because prevention is always preferable to treatment, we reviewed the literature aiming to find an answer for the question whether pHF may be recommended for feeding all infants if breast-feeding is not possible. PubMed and Cochrane databases were searched up to December 2014. In addition, to search for data that remained undetected by the searches, we approached authors of relevant articles and major producers of pHFs asking for unpublished data. Because few data were found, nonrandomized, controlled trials and trials in preterm infants were included as well. Overall, only limited data could be found on the efficacy and safety of pHF in healthy term infants. Available data do not indicate that pHFs are potentially harmful for healthy, term infants. With respect to long-term outcomes, particularly referring to immune, metabolic and hormonal effects, data are, however, nonexistent. From a regulatory point of view, pHFs meet the nutrient requirements to be considered as standard formula for term healthy infants. Cost, which is different from country to country, should be considered in the decision-making process. Based on limited available data, the use of pHF in healthy infants is safe with regard to growth. The lack of data, in particular for metabolic consequences and long-term outcomes, is, however, the basis for our recommendation that health authorities should develop and support long-term follow-up studies. Efficacy and long-term safety data are required before a recommendation of this type of formula for all infants can be made.
Fulltext Metabolic reprogramming and dysregulated metabolism: cause, consequence and/or enabler of environmental carcinogenesis?

Robey RB, Weisz J, Kuemmerle NB, Salzberg AC, Berg A, Brown DG, et al.

Carcinogenesis, 2015 Jun;36 Suppl 1(Suppl 1):S203-31.
PMID: 26106140 DOI: 10.1093/carcin/bgv037

Environmental contributions to cancer development are widely accepted, but only a fraction of all pertinent exposures have probably been identified. Traditional toxicological approaches to the problem have largely focused on the effects of individual agents at singular endpoints. As such, they have incompletely addressed both the pro-carcinogenic contributions of environmentally relevant low-dose chemical mixtures and the fact that exposures can influence multiple cancer-associated endpoints over varying timescales. Of these endpoints, dysregulated metabolism is one of the most common and recognizable features of cancer, but its specific roles in exposure-associated cancer development remain poorly understood. Most studies have focused on discrete aspects of cancer metabolism and have incompletely considered both its dynamic integrated nature and the complex controlling influences of substrate availability, external trophic signals and environmental conditions. Emerging high throughput approaches to environmental risk assessment also do not directly address the metabolic causes or consequences of changes in gene expression. As such, there is a compelling need to establish common or complementary frameworks for further exploration that experimentally and conceptually consider the gestalt of cancer metabolism and its causal relationships to both carcinogenesis and the development of other cancer hallmarks. A literature review to identify environmentally relevant exposures unambiguously linked to both cancer development and dysregulated metabolism suggests major gaps in our understanding of exposure-associated carcinogenesis and metabolic reprogramming. Although limited evidence exists to support primary causal roles for metabolism in carcinogenesis, the universality of altered cancer metabolism underscores its fundamental biological importance, and multiple pleiomorphic, even dichotomous, roles for metabolism in promoting, antagonizing or otherwise enabling the development and selection of cancer are suggested.
Fulltext Assessing the carcinogenic potential of low-dose exposures to chemical mixtures in the environment: the challenge ahead

Goodson WH, Lowe L, Carpenter DO, Gilbertson M, Manaf Ali A, Lopez de Cerain Salsamendi A, et al.

Carcinogenesis, 2015 Jun;36 Suppl 1:S254-96.
PMID: 26106142 DOI: 10.1093/carcin/bgv039

Lifestyle factors are responsible for a considerable portion of cancer incidence worldwide, but credible estimates from the World Health Organization and the International Agency for Research on Cancer (IARC) suggest that the fraction of cancers attributable to toxic environmental exposures is between 7% and 19%. To explore the hypothesis that low-dose exposures to mixtures of chemicals in the environment may be combining to contribute to environmental carcinogenesis, we reviewed 11 hallmark phenotypes of cancer, multiple priority target sites for disruption in each area and prototypical chemical disruptors for all targets, this included dose-response characterizations, evidence of low-dose effects and cross-hallmark effects for all targets and chemicals. In total, 85 examples of chemicals were reviewed for actions on key pathways/mechanisms related to carcinogenesis. Only 15% (13/85) were found to have evidence of a dose-response threshold, whereas 59% (50/85) exerted low-dose effects. No dose-response information was found for the remaining 26% (22/85). Our analysis suggests that the cumulative effects of individual (non-carcinogenic) chemicals acting on different pathways, and a variety of related systems, organs, tissues and cells could plausibly conspire to produce carcinogenic synergies. Additional basic research on carcinogenesis and research focused on low-dose effects of chemical mixtures needs to be rigorously pursued before the merits of this hypothesis can be further advanced. However, the structure of the World Health Organization International Programme on Chemical Safety 'Mode of Action' framework should be revisited as it has inherent weaknesses that are not fully aligned with our current understanding of cancer biology.
Fulltext Predicting attitudinal and behavioral responses to COVID-19 pandemic using machine learning

Pavlović T, Azevedo F, De K, Riaño-Moreno JC, Maglić M, Gkinopoulos T, et al.

PNAS Nexus, 2022 Jul;1(3):pgac093.
PMID: 35990802 DOI: 10.1093/pnasnexus/pgac093

At the beginning of 2020, COVID-19 became a global problem. Despite all the efforts to emphasize the relevance of preventive measures, not everyone adhered to them. Thus, learning more about the characteristics determining attitudinal and behavioral responses to the pandemic is crucial to improving future interventions. In this study, we applied machine learning on the multinational data collected by the International Collaboration on the Social and Moral Psychology of COVID-19 (N = 51,404) to test the predictive efficacy of constructs from social, moral, cognitive, and personality psychology, as well as socio-demographic factors, in the attitudinal and behavioral responses to the pandemic. The results point to several valuable insights. Internalized moral identity provided the most consistent predictive contribution-individuals perceiving moral traits as central to their self-concept reported higher adherence to preventive measures. Similar results were found for morality as cooperation, symbolized moral identity, self-control, open-mindedness, and collective narcissism, while the inverse relationship was evident for the endorsement of conspiracy theories. However, we also found a non-neglible variability in the explained variance and predictive contributions with respect to macro-level factors such as the pandemic stage or cultural region. Overall, the results underscore the importance of morality-related and contextual factors in understanding adherence to public health recommendations during the pandemic.