Cancer incidence in blood transfusion recipients

Transposon DNA sequences facilitate the tissue-specific gene transfer of circulating tumor DNA between human cells

The exchange of genes between cells is known to play an important physiological and pathological role in many organisms. We show that circulating tumor DNA (ctDNA) facilitates cell-specific gene transfer between human cancer cells and explain part of the mechanisms behind this phenomenon. As ctDNA migrates into the nucleus, genetic information is transferred. Cell targeting and ctDNA integration require ERVL, SINE or LINE DNA sequences. Chemically manufactured AluSp and MER11C sequences replicated multiple myeloma (MM) ctDNA cell targeting and integration. Additionally, we found that ctDNA may alter the treatment response of MM and pancreatic cancer models. This study shows that retrotransposon DNA sequences promote cancer gene transfer. However, because cell-free DNA has been detected in physiological and other pathological conditions, our findings have a broader impact than just cancer. Furthermore, the discovery that transposon DNA sequences mediate tissue-specific targeting will open up a new avenue for the delivery of genes and therapies.

Comparison of trace elements in peripheral blood and bone marrow of newly diagnosed multiple myeloma patients

Trace elements are essential micronutrients for the human body. Their roles are indispensable, as they are involved in a wide range of vital biological processes. In this study, we aimed to evaluate alterations in trace elements in the blood and bone marrow serum of patients with newly diagnosed multiple myeloma (NMM). The levels of zinc (Zn), copper (Cu), iron (Fe), manganese (Mn), magnesium (Mg), selenium (Se), arsenic (As), boron (B), nickel (Ni), silicon (Si) and chromium (Cr) were analyzed in the venous blood samples of the patient group comprising 70 patients with NMM (41 males and 29 females) and compared to those in the control group comprising 30 individuals (18 males and 12 females). In addition, trace element levels were analyzed in bone marrow samples from the patient group. Blood and bone marrow serum levels were quantified using inductively coupled plasma optical emission spectrometry. When the blood samples of the patient and control groups were compared: Zn (p = 0.011), Fe (p = 0.008), Mn (p = 0.046), Se (p < 0.001), As (p < 0.001), Ni (p < 0.001) and Cr (p < 0.001) levels were significantly higher in the patient group than in the control group. Higher Zn, Fe, Mn, Se, As, Ni and Cr levels in the NMM patients suggest that alterations of trace elements could be predisposing factor that initiates the malignant process. The relationship between malignancies and trace elements is crucial for the development of adjuvant therapy strategies and preventive medicine and as biomarkers for cancer diagnosis. Therefore, there is a need for studies examining the relationship between hematological malignancies and trace elements.

Therapeutic effect of trace elements on multiple myeloma and mechanisms of cancer process

In the human body, trace elements and other micronutrients play a vital role in growth, health and immune system function. The trace elements are Iron, Manganese, Copper, Iodine, Zinc, Cobalt, Fluoride, and Selenium. Estimating the serum levels of trace elements in hematologic malignancy patients can determine the severity of the tumor. Multiple myeloma (MM) is a hematopoietic malignancy and is characterized by plasma cell clonal expansion in bone marrow. Despite the advances in treatment methods, myeloma remains largely incurable. In addition to conventional medicine, treatment is moving toward less expensive noninvasive alternatives. One of the alternative treatments is the use of dietary supplements. In this review, we focused on the effect of three trace elements including iron, zinc and selenium on important mechanisms such as the immune system, oxidative and antioxidant factors and cell cycle. Using some trace minerals in combination with approved drugs can increase patients' recovery speed. Trace elements can be used as not only a preventive but also a therapeutic tool, especially in reducing inflammation in hematological cancers such as multiple myeloma. We hope that the prospect of the correct use of trace element supplements in the future could be promising for the treatment of diseases.

Six-transmembrane epithelial antigen of prostate 3 (STEAP3) is a potential prognostic biomarker in clear cell renal cell carcinoma that correlates with M2 macrophage infiltration and epithelial-mesenchymal

BACKGROUND

The six-transmembrane epithelial antigen of the prostate 3 (STEAP3) is a metalloreductase, which is essential for iron uptake. Existing literature has shown that STEAP3 may perform an important role in the onset and progression of tumors. Nonetheless, a complete pan-cancer investigation of the prognostic significance and immune properties of STEAP3 is currently unavailable.

AIMS

As part of our investigation into the possible functions of STEAP3 in malignancies, we conducted a comprehensive analysis to examine the prognostic value and immune features of STEAP3 in human pan-cancer.

METHODS AND RESULTS

R and Cytoscape programs were applied to analyze and visualize the data. The expression of STEAP3 in both cell lines and tissues was measured utilizing a variety of approaches. Using the shRNA knockdown technique, we tested the viability of the A498 and 786-O cell lines and validated their functions. Both CCK-8 and transwell assays were conducted to estimate cell proliferation and invasion. The expression of STEAP3 was substantially elevated and was shown to be linked to prognosis in the majority of malignancies, notably in clear cell renal cell carcinoma (ccRCC). In addition, the expression of STEAP3 was shown to have a strong correlation with immune infiltrates, which in turn triggered the recruitment and polarization of M2 macrophages in ccRCC. The protein STEAP3 shows promise as a predictor of responses to immune-checkpoint blockade (ICB) therapy. Positive links between STEAP3 and the epithelial-mesenchymal transition (EMT), the p53 pathway, and the immune-associated pathways were also found in the enrichment analysis. Our results illustrated that the STEAP3 expression level was substantially elevated in ccRCC tissues and suggested that it could stimulate EMT in ccRCC by downregulating CDH1.

CONCLUSION

In a diverse range of cancers, STEAP3 might serve as a biomarker for determining the prognosis as well as a predictor of immunotherapy responsiveness. STEAP3 is a novel biological marker for determining prognosis, and it also performs a remarkable function in the promotion of tumor growth in ccRCC by enhancing invasion and EMT, as well as by triggering the recruitment and polarization of M2 macrophages.

Dynamic chromatin accessibility during nutritional iron overload reveals a BMP6-independent induction of cell cycle genes

Iron is essential to organism physiology as it participates in numerous biological processes including oxygen transport, respiration and erythropoiesis. Although iron is critical to physiology, excess iron is toxic to cells and tissues due to generation of reactive oxygen species. Therefore, well-kept iron homeostasis is a mainstay of proper cell and organ function. Iron overload disorders, caused by nutritional or genetic factors, contribute to many pathologies such as diabetes, non-alcoholic steatohepatitis and hepatocellular carcinoma. The liver is not only vulnerable to the effects of iron overload, it is also the major organ controlling iron homeostasis. During iron overload, Bone Morphogenic Protein (BMP) levels increase and initiate a hepatic response aimed at lowering iron levels. The transcriptional effects of iron overload are not well-characterized and the underlining enhancer regulation is uncharted. Here, we profiled the liver's transcriptome and chromatin accessibility following nutritional iron overload. We found marked changes in gene expression and enhancer accessibility following iron overload. Surprisingly, 16% of genes induced following iron overload participate in propagating the cell cycle. Induction of cell cycle genes was independent of BMP. Genome-wide enhancer landscape profiling revealed hundreds of enhancers with altered activity following iron overload. Characterization of transcription factor motifs and footprints in iron-regulated enhancers showed a role for the Activator Protein 1 (AP-1) transcription factor in promoting cell cycle-related transcription. In summary, we found that the transcriptional program at play during iron overload is bifurcated in which BMP signaling controls iron homeostasis genes while an AP-1-driven program controls cell cycle genes.

Iron deficiency screening is a key issue in chronic inflammatory diseases: A call to action

Iron deficiency is frequent in patients with chronic inflammatory conditions (e.g., chronic heart failure, chronic kidney disease, cancers, and bowel inflammatory diseases). Indeed, high concentrations of inflammatory cytokines increase hepcidin concentrations that lead to the sequestration of iron in cells of the reticuloendothelial system (functional iron deficiency). Iron parameters are often assessed only in the context of anemia, but iron deficiency, even without anemia, is present in about half of patients with inflammatory conditions. Iron deficiency worsens underlying chronic diseases and is an independent factor of morbidity and mortality. In daily practice, the most effective biomarkers of iron status are serum ferritin, which reflects iron storage, and transferrin saturation, which reflects the transport of iron. Serum ferritin is increased in an inflammatory context, and there is still no consensus on the threshold to be used in chronic inflammatory conditions. Nevertheless, recent recommendations of international guidelines agreed to define iron deficiency by serum ferritin &lt;100 µg/L and/or transferrin saturation &lt;20%. Iron parameters remain, however, insufficiently assessed in patients with chronic inflammatory conditions. Indeed, clinical symptoms of iron deficiency, such as fatigue, are not specific and often confused with those of the primary disease. Iron repletion, preferably by the intravenous route to bypass tissue sequestration, improves clinical signs and quality of life. Because of the negative impact of iron deficiency on chronic inflammatory diseases and the efficacy of intravenous iron repletion, screening of iron parameters should be part of the routine examination of all patients with chronic inflammatory diseases.

Nrf2 Is a Potential Modulator for Orchestrating Iron Homeostasis and Redox Balance in Cancer Cells

Iron is an essential trace mineral element in almost all living cells and organisms. However, cellular iron metabolism pathways are disturbed in most cancer cell types. Cancer cells have a high demand of iron. To maintain rapid growth and proliferation, cancer cells absorb large amounts of iron by altering expression of iron metabolism related proteins. However, iron can catalyze the production of reactive oxygen species (ROS) through Fenton reaction. Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is an important player in the resistance to oxidative damage by inducing the transcription of antioxidant genes. Aberrant activation of Nrf2 is observed in most cancer cell types. It has been revealed that the over-activation of Nrf2 promotes cell proliferation, suppresses cell apoptosis, enhances the self-renewal capability of cancer stem cells, and even increases the chemoresistance and radioresistance of cancer cells. Recently, several genes involving cellular iron homeostasis are identified under the control of Nrf2. Since cancer cells require amounts of iron and Nrf2 plays pivotal roles in oxidative defense and iron metabolism, it is highly probable that Nrf2 is a potential modulator orchestrating iron homeostasis and redox balance in cancer cells. In this hypothesis, we summarize the recent findings of the role of iron and Nrf2 in cancer cells and demonstrate how Nrf2 balances the oxidative stress induced by iron through regulating antioxidant enzymes and iron metabolism. This hypothesis provides new insights into the role of Nrf2 in cancer progression. Since ferroptosis is dependent on lipid peroxide and iron accumulation, Nrf2 inhibition may dramatically increase sensitivity to ferroptosis. The combination of Nrf2 inhibitors with ferroptosis inducers may exert greater efficacy on cancer therapy.

Ironing out mechanisms of iron homeostasis and disorders of iron deficiency

Iron plays an important role in mammalian physiological processes. It is a critical component for the function of many proteins, including enzymes that require heme and iron-sulfur clusters. However, excess iron is also detrimental because of its ability to catalyze the formation of reactive oxygen species. As a result, cellular and systemic iron levels are tightly regulated to prevent oxidative damage. Iron deficiency can lead to a number of pathological conditions, the most prominent being anemia. Iron deficiency should be corrected to improve adult patients' symptoms and to facilitate normal growth during fetal development and childhood. However, inappropriate use of intravenous iron in chronic conditions, such as cancer and heart failure, in the absence of clear iron deficiency can lead to unwanted side effects. Thus, this form of therapy should be reserved for certain patients who cannot tolerate oral iron and need rapid iron replenishment. Here, we will review cellular and systemic iron homeostasis and will discuss complications of iron deficiency.

[Safety of cell salvage in tumor surgery : Systematic review with meta-analysis]

BACKGROUND

Allogeneic blood transfusion is avoidable in many oncological interventions by the use of cell salvage or mechanical autotransfusion (MAT). As irradiation is elaborate and expensive, the safety of leucocyte depletion filters (LDF) for autologous blood from the surgical field might be a more acceptable alternative for the prevention of cancer recurrences. A previous meta-analysis could not identify an increased risk of cancer recurrence. The aim of this review article is to provide an update of a previous meta-analysis from 2012 as well as a safety analysis of cell salvage with LDF due to the improved data situation.

MATERIAL AND METHODS

This systematic review included all studies in PubMed, Cochrane, Cochrane Reviews and Web of Science on cell salvage or autotransfusion combined with outcomes, e.g. cancer recurrence, mortality, survival, blood transfusion, length of hospital stay (LOS) after the use of MAT without irradiation and with or without LDF. The grades of recommendations (GRADE) assessment of underlying evidence was applied.

RESULTS

A total of seven new observational studies and seven meta-analyses were found that compared unfiltered or filtered cell salvage with autologous predeposition, allogeneic transfusion or without any transfusion. No randomized controlled trials have been completed. A total of 27 observational and cohort studies were included in a meta-analysis. The evidence level was low. The risk of cancer recurrence in recipients of autologous salvaged blood with or without LDF was reduced (odds ratio, OR 0.71, 95% confidence interval, CI 0.58-0.86) as compared to non-transfused subjects, allogeneic or predeposited autologous transfusion. The transfusion rate could not be assessed due to the substantial selection bias and large heterogeneity. Cell salvage does not change mortality and LOS. Leucocyte depletion studies reported a removal rate of cancer cells in the range of 99.6-99.9%.

CONCLUSION

Randomized controlled trials on a comparison of MAT and allogeneic blood transfusion as well as LDF and irradiation would be desirable but are not available. From observational trials and more than 6300 subjects and various tumors, cell salvage in cancer surgery with or without LDF appears to be sufficiently safe. The efficacy of leucocyte depletion of autologous salvaged blood is equivalent to irradiation. Unavailability of radiation is not a contraindication for cell salvage use in cancer surgery. By usage of leucocyte depleted salvaged autologous blood, the risks of allogeneic transfusion can be avoided.

Blood transfusions may adversely affect survival outcomes of patients with lung cancer: a systematic review and meta-analysis

Background

Despite common use in clinical practice, the impact of blood transfusions on prognosis among patients with lung cancer remains unclear. The purpose of the current study is to perform an updated systematic review and meta-analysis to evaluate the influence of blood transfusions on survival outcomes of lung cancer patients.

Methods

We searched PubMed, Embase, Cochrane Library, and Ovid MEDLINE for publications illustrating the association between blood transfusions and prognosis among people with lung cancer from inception to November 2019. Overall survival (OS) and disease-free survival (DFS) were the outcomes of interest. Pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were computed using the random-effects model. Study heterogeneity was evaluated with the I² test. Publication bias was explored via funnel plot and trim-and-fill analyses.

Results

We included 23 cohort studies with 12,175 patients (3,027 cases and 9,148 controls) for meta-analysis. Among these records, 22 studies investigated the effect of perioperative transfusions, while one examined that of transfusions during chemotherapy. Two studies suggested the possible dose-dependent effect in accordance with the number of transfused units. In pooled analyses, blood transfusions deleteriously influenced both OS (HR=1.35, 95% CI: 1.14–1.61, P<0.001, I²=0%) and DFS (HR=1.46, 95% CI: 1.15–1.86, P=0.001, I²=0%) of people with lung cancer. No evidence of significant publication bias was detected in funnel plot and trim-and-fill analyses (OS: HR=1.26, 95% CI: 1.07–1.49, P=0.006; DFS: HR=1.35, 95% CI: 1.08–1.69, P=0.008).

Conclusions

Blood transfusions were associated with decreased survival of patients with lung cancer.

Iron: An Essential Element of Cancer Metabolism

Cancer cells undergo considerable metabolic changes to foster uncontrolled proliferation in a hostile environment characterized by nutrient deprivation, poor vascularization and immune infiltration. While metabolic reprogramming has been recognized as a hallmark of cancer, the role of micronutrients in shaping these adaptations remains scarcely investigated. In particular, the broad electron-transferring abilities of iron make it a versatile cofactor that is involved in a myriad of biochemical reactions vital to cellular homeostasis, including cell respiration and DNA replication. In cancer patients, systemic iron metabolism is commonly altered. Moreover, cancer cells deploy diverse mechanisms to increase iron bioavailability to fuel tumor growth. Although iron itself can readily participate in redox reactions enabling vital processes, its reactivity also gives rise to reactive oxygen species (ROS). Hence, cancer cells further rely on antioxidant mechanisms to withstand such stress. The present review provides an overview of the common alterations of iron metabolism occurring in cancer and the mechanisms through which iron promotes tumor growth.

Blood Transfusion and the Risk of Cancer in the US Population: Is There an Association?

Purpose

We aimed to test if blood transfusion is a risk factor for the prevalence of cancer.

Patients and Methods

We conducted secondary analyses using the NHANES database from 1999 to 2016. We included all individuals who received a blood transfusion with known cancer comorbidity (diseased or not). We used univariate logistic regression to identify any possible association between history of blood transfusion and the prevalence of cancer with adjustment for different co-founders was done. Regression results were expressed as odds ratios (ORs) and 95% confidence interval (95% CI) for both adjusted and unadjusted models.

Results

A total of 48,796 individuals were included in the final analysis: 6333 of them received a blood transfusion, while the other 42,463 individuals did not. In individuals who received a blood transfusion, the most prevalent cancer was breast cancer (3.4%), followed by prostate (3.0%), non-melanoma skin (2.4%) cancers, while non-melanoma skin (1.2%), prostate (1.1%) and breast (1.1%) cancers were the most prevalent in the no transfusion individuals. There was a significant association between the reported history of blood transfusion and the overall prevalence of cancer in both the unadjusted (OR= 3.47; 95% CI= 3.23–0.72; P-value< 0.001) and adjusted model (OR= 1.86; 95% CI= 1.72–0.2.01; P-value< 0.001). On the level of individual cancers, a significant reduction in cancer prevalence was found in patients with breast, cervix, larynx, Hodgkin’s lymphoma, melanoma, prostate, skin (non-melanoma), skin (unspecified), soft tissue, testicular, thyroid, and uterine cancers.

Conclusion

Results did not imply any concrete association between cancer risk and history of blood transfusion. These findings would help in debunking the myth of increased cancer risk following blood transfusion.

Peripartum Blood Transfusions are Associated with Increased Risk of Cancer: A National Retrospective Cohort Study

Background

The effect of blood transfusions on the risk of developing primary cancer remains unclear, especially when administered in the peripartum period.

Materials and Methods

We conducted a retrospective cohort study of 270,529 pregnant women who delivered between January 1, 2007 and December 31, 2009, with data obtained from three national databases in South Korea. From this cohort, we identified 4569 patients who received peripartum blood transfusions. We calculated hazard ratios (HRs) for new diagnoses of cancer and adjusted them for relevant clinical factors using a Cox proportional hazards model.

Results

During follow-up, patients who received peripartum transfusions had an increased risk of developing cancer, with an adjusted HR of 1.16 (95% confidence interval [CI], 1.01–1.34). In a subgroup analysis, this risk was significant only among patients who received 3 or more units of blood, with an adjusted HR of 1.40 (95% CI, 1.10–1.79). Increased risk after transfusions were seen with brain, lung, ovarian, and gallbladder cancers. The difference in cancer risk between the transfusion and no-transfusion groups remained significant during both the first (1.29% vs 1.07%, p < 0.01) and second year (0.74% vs 0.56%, p < 0.01) after delivery.

Conclusion

Receipt of 3 or more blood transfusions in the peripartum period was associated with a significantly increased risk of developing cancer. Prospective studies should be pursued to further understand the link between blood transfusions and long-term oncologic risks.

Iron: The cancer connection

Iron plays an essential role in normal biological processes: The generation of cellular energy, oxygen transport, DNA synthesis and repair are all processes that require iron-coordinated proteins, either as elemental iron, heme or iron-sulfur clusters. As a transition metal with two major biological oxidation states, iron is also a critical intermediate in the generation of reactive oxygen species that can damage cellular structures and contribute to both aging and cancer. In this review, we focus on experimental and epidemiologic evidence that links iron and cancer, as well as strategies that have been proposed to either reduce or increase cellular iron for cancer therapy.

Prediction of perioperative transfusions using an artificial neural network

BACKGROUND

Accurate prediction of operative transfusions is essential for resource allocation and identifying patients at risk of postoperative adverse events. This research examines the efficacy of using artificial neural networks (ANNs) to predict transfusions for all inpatient operations.

METHODS

Over 1.6 million surgical cases over a two year period from the NSQIP-PUF database are used. Data from 2014 (750937 records) are used for model development and data from 2015 (885502 records) are used for model validation. ANN and regression models are developed to predict perioperative transfusions for surgical patients.

RESULTS

Various ANN models and logistic regression, using four variable sets, are compared. The best performing ANN models with respect to both sensitivity and area under the receiver operator characteristic curve outperformed all of the regression models (p < .001) and achieved a performance of 70-80% specificity with a corresponding 75-62% sensitivity.

CONCLUSION

ANNs can predict >75% of the patients who will require transfusion and 70% of those who will not. Increasing specificity to 80% still enables a sensitivity of almost 67%. The unique contribution of this research is the utilization of a single ANN model to predict transfusions across a broad range of surgical procedures.

Blood transfusion history and risk of non-Hodgkin lymphoma: an InterLymph pooled analysis

PURPOSE

To conduct a pooled analysis assessing the association of blood transfusion with risk of non-Hodgkin lymphoma (NHL).

METHODS

We used harmonized data from 13 case-control studies (10,805 cases, 14,026 controls) in the InterLymph Consortium. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using unconditional logistic regression, adjusted for study design variables.

RESULTS

Among non-Hispanic whites (NHW), history of any transfusion was inversely associated with NHL risk for men (OR 0.74; 95% CI 0.65-0.83) but not women (OR 0.92; 95% CI 0.83-1.03), pheterogeneity = 0.014. Transfusion history was not associated with risk in other racial/ethnic groups. There was no trend with the number of transfusions, time since first transfusion, age at first transfusion, or decade of first transfusion, and further adjustment for socioeconomic status, body mass index, smoking, alcohol use, and HCV seropositivity did not alter the results. Associations for NHW men were stronger in hospital-based (OR 0.56; 95% CI 0.45-0.70) but still apparent in population-based (OR 0.84; 95% CI 0.72-0.98) studies.

CONCLUSIONS

In the setting of a literature reporting mainly null and some positive associations, and the lack of a clear methodologic explanation for our inverse association restricted to NHW men, the current body of evidence suggests that there is no association of blood transfusion with risk of NHL.

Iron and Cancer

This review explores the multifaceted role that iron has in cancer biology. Epidemiological studies have demonstrated an association between excess iron and increased cancer incidence and risk, while experimental studies have implicated iron in cancer initiation, tumor growth, and metastasis. The roles of iron in proliferation, metabolism, and metastasis underpin the association of iron with tumor growth and progression. Cancer cells exhibit an iron-seeking phenotype achieved through dysregulation of iron metabolic proteins. These changes are mediated, at least in part, by oncogenes and tumor suppressors. The dependence of cancer cells on iron has implications in a number of cell death pathways, including ferroptosis, an iron-dependent form of cell death. Uniquely, both iron excess and iron depletion can be utilized in anticancer therapies. Investigating the efficacy of these therapeutic approaches is an area of active research that promises substantial clinical impact.

Iron Metabolism in Prostate Cancer; From Basic Science to New Therapeutic Strategies

An increasing amount of research has recently strengthened the case for the existence of iron dysmetabolism in prostate cancer. It is characterized with a wide array of differential expression of iron-related proteins compared to normal cells. These proteins control iron entry, cellular iron distribution but also iron exit from prostate cells. Iron dysmetabolism is not an exclusive feature of prostate cancer cells, but it is observed in other cells of the tumor microenvironment. Disrupting the machinery that secures iron for prostate cancer cells can retard tumor growth and its invasive potential. This review unveils the current understanding of the ways that prostate cancer cells secure iron in the tumor milieu and how can we exploit this knowledge for therapeutic purposes.

Storage time of platelet concentrates and risk of a positive blood culture: a nationwide cohort study

BACKGROUND

Concern of transfusion-transmitted bacterial infections has been the major hurdle to extend shelf life of platelet (PLT) concentrates. We aimed to investigate the association between storage time and risk of positive blood cultures at different times after transfusion.

STUDY DESIGN AND METHODS

We performed a nationwide cohort study among PLT transfusion recipients in Denmark between 2010 and 2012, as recorded in the Scandinavian Donations and Transfusions (SCANDAT2) database. Linking with a nationwide database on blood cultures (MiBa), we compared the incidence of a positive blood culture among recipients of PLTs stored 6 to 7 days (old) to those receiving fresh PLTs (1-5 days), using Poisson regression models. We considered cumulative exposures in windows of 1, 3, 5, and 7 days.

RESULTS

A total of 9776 patients received 66,101 PLT transfusions. The incidence rate ratio (IRR) of a positive blood culture the day after transfusion of at least one old PLT concentrate was 0.77 (95% confidence interval [CI], 0.54-1.09) compared to transfusion of fresh PLT concentrates. The incidence rate of a positive blood culture was lower the day after receiving one old compared to one fresh PLT concentrate (IRR, 0.57; 95% CI, 0.37-0.87). Three, 5, or 7 days after transfusion, storage time was not associated with the risk of a positive blood culture.

CONCLUSION

Storage of buffy coat-derived PLT concentrates in PAS-C up to 7 days seems safe regarding the risk of a positive blood culture. If anything, transfusion of a single old PLT concentrate may decrease this risk the following day.

Epidemiology of donors and recipients: lessons from the SCANDAT database

With the development of several 'vein-to-vein' databases, which capture data on the entire donor-recipient continuum and link this data to health outcomes, there has been an increasing number of studies investigating the health effects of all aspects of the practice of transfusion medicine. The Scandinavian Donations and Transfusions (SCANDAT) database is one of several such databases, which includes all electronically available data on blood donors, donations and transfusions since the late 1960s in Sweden and the early 1980s in Denmark. The SCANDAT database has been used to characterise disease occurrence among blood donors and transfused patients, as well as to investigate possible health effects of blood donations, aspects of transfusion care and possible transfusion transmission of disease. Recent publications include studies on recipient mortality associated with the storage lesion, studies on the effects of donor demographics on patient mortality and health effects of frequent blood donation. Although this research approach is clearly very powerful, the appropriate analysis of such real-world data is complex and requires close methodological attention. The purpose of this review is to present some of the research conducted within the SCANDAT collaboration. We hope more international collaboration may help improve our understanding of the important remaining questions about donor and recipient health.

Taming the immune system through transfusion in oncology patients

Blood transfusion is a clinical replacement therapy with many successes with some benefit and, also, some harm. Cancer is a multifaceted disease potentially associated with the immune system's weakness where the cancerous tumor cells escape from the immune system. Allogeneic blood transfusion, through five major mechanisms including the lymphocyte-T set, myeloid-derived suppressor cells (MDSCs), tumor-associated macrophages (TAMs), natural killer cells (NKCs), and dendritic cells (DCs) can help the recipient's defense mechanisms. On the other hand, the role for each of the listed items includes activation of the antitumor CD8+ cytotoxic T lymphocytes (CD8+/CTL), temporal inactivation of Tregs, inactivation of the STAT3 signaling pathway, the use of bacteria to enhance the antitumor immune response and cellular immunotherapy. The above issues are concisely addressed in this manuscript based on a literature survey on this topic carried out by the first author.

Cancer risk among 21st century blood transfusion recipients

Background

Some carcinogenic viruses are known to be transmissible by blood transfusion. Intensive viral screening of transfused blood now exists in most countries. In the UK, high-sensitivity nucleic acid amplification tests for hepatitis C virus were introduced in 1999 and it was thought that this would reduce, and possibly eliminate, transfusion-related liver cancer. We aimed to investigate cancer risk in recipients of blood transfusion in 2000 or after.

Methods

A total of 1.3 million UK women recruited in 1998 on average were followed for hospital records of blood transfusion and for cancer registrations. After excluding women with cancer or precancerous conditions before or at the time of transfusion, Cox regression yielded adjusted relative risks of 11 site-specific cancers for women with compared to without prior blood transfusion.

Results

During follow up, 11 274 (0.9%) women had a first recorded transfusion in 2000 or after, and 1648 (14.6%) of them were subsequently diagnosed with cancer, a mean 6.8 years after the transfusion. In the first 5 years after transfusion there were significant excesses for most site-specific cancers examined, presumably because some had preclinical cancer. However, 5 or more years (mean 8 years) after blood transfusion, there were significant excess risks only for liver cancer (adjusted relative risk = 2.63, 95%CI 1.45-4.78) and for non-Hodgkin lymphoma (adjusted relative risk = 1.74, 1.21-2.51). When analyses were restricted to those undergoing hip or knee replacement surgery, the commonest procedure associated with transfusion, these relative risks were not materially altered.

Conclusions

In a large cohort of UK women, transfusions in the 21st century were associated with long-term increased risks of liver cancer and non-Hodgkin lymphoma. Some of these malignancies may have been caused by carcinogenic agents that are not currently screened for in transfused blood.

Marseillevirus in lymphoma: a giant in the lymph node

The family Marseilleviridae is a new clade of giant viruses whose original member, marseillevirus, was described in 2009. These viruses were isolated using Acanthamoeba spp primarily from the environment. Subsequently, a close relative of marseillevirus was isolated from the faeces of a healthy young man, and others were detected in blood samples of blood donors and recipients and in a child with lymph node adenitis. In this Grand Round we describe the detection of marseillevirus by PCR, fluorescence in-situ hybridisation, direct immunofluorescence, and immunohistochemistry in the lymph node of a 30-year-old woman diagnosed with Hodgkin's lymphoma, together with IgG antibodies to marseillevirus. A link with viruses and bacteria has been reported for many lymphomas. We review the literature describing these associations, the criteria used to consider a causal association, and the underlying mechanisms of lymphomagenesis. Our observations suggest that consideration should be given to marseillevirus infections as an additional viral cause or consequence of Hodgkin's lymphoma, and that this hypothesis should be tested further.

Protocol for a national blood transfusion data warehouse from donor to recipient

INTRODUCTION

Blood transfusion has health-related, economical and safety implications. In order to optimise the transfusion chain, comprehensive research data are needed. The Dutch Transfusion Data warehouse (DTD) project aims to establish a data warehouse where data from donors and transfusion recipients are linked. This paper describes the design of the data warehouse, challenges and illustrative applications.

STUDY DESIGN AND METHODS

Quantitative data on blood donors (eg, age, blood group, antibodies) and products (type of product, processing, storage time) are obtained from the national blood bank. These are linked to data on the transfusion recipients (eg, transfusions administered, patient diagnosis, surgical procedures, laboratory parameters), which are extracted from hospital electronic health records.

APPLICATIONS

Expected scientific contributions are illustrated for 4 applications: determine risk factors, predict blood use, benchmark blood use and optimise process efficiency. For each application, examples of research questions are given and analyses planned.

CONCLUSIONS

The DTD project aims to build a national, continuously updated transfusion data warehouse. These data have a wide range of applications, on the donor/production side, recipient studies on blood usage and benchmarking and donor-recipient studies, which ultimately can contribute to the efficiency and safety of blood transfusion.

Up-regulation of NKG2A inhibitory receptor on circulating NK cells contributes to transfusion-induced immunodepression in patients with β-thalassemia major

Accumulating evidence has shown that allogeneic blood transfusions can induce significant immunosuppression in recipients, and thereby increase the risk of postoperative infection and/or tumor relapse. Although it is well known that natural killer (NK) cells are responsible for the immunodepression effects of transfusion, the underlying mechanisms remain obscure. In this study, we investigated the role of NK cells in transfusion-induced immunodepression in β-thalassemia major. The proportion of circulating NK cells and the expression of NK receptors (NKG2A, CD158a, NKP30, NKP46 and NKG2D) as well as CD107a were detected by multicolor flow cytometry. IFN-γ production by circulating NK cells was detected by intracellular cytokine staining. Our results showed that the proportion and cytotoxicity (CD107a expression) of circulating NK cells in transfusion-dependent β-thalassemia major patients were remarkably lower than those of β-thalassemia minor patients or healthy volunteers. Expression of NKG2A inhibitory receptor on circulating NK cells in patients with β-thalassemia major was remarkably up-regulated, but there were no significant differences in the expression levels of NKP30, NKP46, NKG2D, CD158a and IFN-γ. These results indicate NKG2A inhibitory receptor may play a key role in transfusion-induced immunodepression of NK cells in patients with β-thalassemia major.

Impact of Transfusion on Cancer Growth and Outcome

For many years, transfusion of allogeneic red blood cells, platelet concentrates, and plasma units has been part of the standard therapeutic arsenal used along the surgical and nonsurgical treatment of patients with malignancies. Although the benefits of these blood products are not a matter of debate in specific pathological conditions associated with life-threatening low blood cell counts or bleeding, increasing clinical evidence is nevertheless suggesting that deliberate transfusion of these blood components may actually lead to negative clinical outcomes by affecting patient’s immune defense, stimulating tumor growth, tethering, and dissemination. Rigorous preclinical and clinical studies are needed to dimension the clinical relevance, benefits, and risks of transfusion of blood components in cancer patients and understand the amplitude of problems. There is also a need to consider validating preparation methods of blood components for so far ignored biological markers, such as microparticles and biological response modifiers. Meanwhile, blood component transfusions should be regarded as a personalized medicine, taking into careful consideration the status and specificities of the patient, rather than as a routine hospital procedure.

Blood donation and risk of polycythemia vera

BACKGROUND

It has been suggested that blood donors could have an increased risk of polycythemia vera (PV). However, no study has assessed whether frequent donors have a higher PV risk than less frequent donors.

STUDY DESIGN AND METHODS

From the Scandinavian Donations and Transfusions (SCANDAT2) database, we established a cohort of blood donors who had donated whole blood at least once between 1980 and 2012. Within this cohort we first assessed the risk of PV, comparing the donors to the general population using standardized incidence ratios (SIRs) with corresponding 95% confidence intervals (CIs). To assess the association between frequency of blood donation and risk of PV we then conducted a case-control study nested within the cohort, where we compared prior donation activity among donors who were diagnosed with PV and matched controls. Here odds ratios (ORs) were used as measures of relative risk comparing donors with different donation frequency.

RESULTS

Among 1.4 million donors in the cohort a total of 271 donors developed PV, yielding a SIR of 1.00 (95% CI, 0.89-1.13) compared to the general population. The nested case-control study showed no association between donation frequency and risk of PV. The OR of PV comparing donors who had made at least 33 donations in the period from 3 to 22 years before diagnosis of the case, to donors with one to eight donations in the same period was 1.01 (95% CI, 0.51-1.97).

CONCLUSIONS

We find no evidence of excess risk of PV among blood donors or of an association between donation frequency and PV risk.

Epstein- Barr Virus: Clinical and Epidemiological Revisits and Genetic Basis of Oncogenesis

Epstein-Barr virus (EBV) is classified as a member in the order herpesvirales, family herpesviridae, subfamily gammaherpesvirinae and the genus lymphocytovirus. The virus is an exclusively human pathogen and thus also termed as human herpesvirus 4 (HHV4). It was the first oncogenic virus recognized and has been incriminated in the causation of tumors of both lymphatic and epithelial nature. It was reported in some previous studies that 95% of the population worldwide are serologically positive to the virus. Clinically, EBV primary infection is almost silent, persisting as a life-long asymptomatic latent infection in B cells although it may be responsible for a transient clinical syndrome called infectious mononucleosis. Following reactivation of the virus from latency due to immunocompromised status, EBV was found to be associated with several tumors. EBV linked to oncogenesis as detected in lymphoid tumors such as Burkitt's lymphoma (BL), Hodgkin's disease (HD), post-transplant lymphoproliferative disorders (PTLD) and T-cell lymphomas (e.g. Peripheral T-cell lymphomas; PTCL and Anaplastic large cell lymphomas; ALCL). It is also linked to epithelial tumors such as nasopharyngeal carcinoma (NPC), gastric carcinomas and oral hairy leukoplakia (OHL). In vitro, EBV many studies have demonstrated its ability to transform B cells into lymphoblastoid cell lines (LCLs). Despite these malignancies showing different clinical and epidemiological patterns when studied, genetic studies have suggested that these EBV- associated transformations were characterized generally by low level of virus gene expression with only the latent virus proteins (LVPs) upregulated in both tumors and LCLs. In this review, we summarize some clinical and epidemiological features of EBV- associated tumors. We also discuss how EBV latent genes may lead to oncogenesis in the different clinical malignancies

Iron, human growth, and the global epidemic of obesity

Iron is an essential nutrient utilized in almost every aspect of cell function and its availability has previously limited life. Those same properties which allow iron to function as a catalyst in the reactions of life also present a threat via generation of oxygen-based free radicals. Accordingly; life exists at the interface of iron-deficiency and iron-sufficiency. We propose that: (1) human life is no longer positioned at the limits of iron availability following several decades of fortification and supplementation and there is now an overabundance of the metal among individuals of many societies; (2) this increased iron availability exerts a positive effect on growth by targeting molecules critical in regulating the progression of the cell cycle; there is increased growth in humans provided greater amounts of this metal; and indices of obesity can positively correlate with body stores of iron; and (3) diseases of obesity reflect this over-abundance of iron. Testing potential associations between iron availability and both obesity and obesity-related diseases in populations will be difficult since fortification and supplementation is so extensively practiced.

Blood transfusions and the subsequent risk of cancers in the United States elderly

BACKGROUND

Blood transfusions are common in older adults and also may modulate the immune system. However, the impact of transfusion on cancer risk in the elderly has not been studied.

STUDY DESIGN AND METHODS

Cancer risk after blood transfusion was evaluated in a US population-based case-control study using 552,951 elderly cases identified from cancer registries and 100,000 frequency-matched controls. Transfusions received 0 to 12, 13 to 30, and 31 to 48 months before cancer diagnosis or selection date were identified using Medicare claims. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression models. A Bonferroni correction adjusted for multiple testing.

RESULTS

Transfusions received 0 to 12 months before cancer diagnosis and/or selection were associated with significantly elevated risk of cancer overall (OR,2.05; 95% CI, 1.95-2.16) and cancer of the stomach; cancer of the colon; cancer of the liver, kidney, renal pelvis, and/or ureter; lymphoma; myeloma; and leukemia. No significant associations for cancer overall were observed for the two earlier intervals. No site was associated with transfusions received 13 to 30 or 31 to 48 months before diagnosis and/or selection. Nonetheless, overall cancer risk increased with the number of transfused periods (p-trend<0.0001).

CONCLUSION

Risk of overall cancer and specific sites was elevated 0 to 12 months after blood transfusion and associated with multiple transfusions, possibly due to reverse causation, that is, incipient cancers or cancer precursors causing anemia.

Time interval from cigarette smoke exposure to blood donation and markers of inflammation: should a smoking cut-off be designated?

Allogeneic blood transfusion leads to the infusion into the recipient of large amounts of antigens that may create conditions which are related to immune system modulation. The aim of this study was to determine the effects of smoking habit on vascular endothelial growth factor (VEGF) and interleukin 6 (IL-6) levels in the plasma of blood donors. Blood samples from 170 consecutive blood donors was collected and analyzed for serum markers, while questionnaire data was collected. Serum cotinine levels were calculated for non-smokers, while serum cytokine IL-6 and VEGF concentrations were also calculated among 88 randomly selected subjects. Controlling for the donors age and gender, a strong tendency was found for smoking within 24 h of the blood donation to be associated with a higher VEGF concentration of the donated blood (ß = 141.13, p = 0.06), while the donor age was independently related to VEGF levels (p = 0.001). Additionally the IL-6 levels in the transfused blood were independently associated with the donors age (p = 0.001) and gender (p = 0.002) but not with their smoking status. Further research is needed so as to assess the need of updating blood donation guide lines to regulate the time intervals between the time from the last cigarette and blood donation.

Association between red blood cell transfusions and development of non-Hodgkin lymphoma: a meta-analysis of observational studies

The incidence of non-Hodgkin lymphoma (NHL) has increased steadily for the past few decades. Previous studies have suggested an association between blood transfusions and NHL. The main objective of this study was to evaluate this relationship with a meta-analysis of observational studies. A literature search was undertaken, looking for case-control and cohort studies evaluating the risk of developing NHL in persons who received allogeneic blood transfusions; 14 studies were included. Outcome was calculated and reported as relative risk (RR). Heterogeneity was assessed with Cochrane Q and I2 statistics. Dissemination bias was evaluated by funnel plot visualization and trim-and-fill analysis. Quality assessment was performed with the Newcastle-Ottawa scale. Our analysis showed a RR of developing NHL of 1.05 (95% CI, 0.89-1.25; P = .42) and 1.34 (95% CI, 1.15-1.55; P < .01) in case-control and cohort studies, respectively. When pooling all studies, RR was 1.2 (95% CI, 1.07-1.35; P < .01). In subset analysis, RR of chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) was 1.66 (95% CI, 1.08-2.56; P = .02). The RR of NHL was elevated in both men and women and in persons receiving transfusions either before or after 1992. Blood transfusions appear to increase the risk of developing NHL; however, the risk of CLL/SLL appears higher than for other NHL subtypes.

Blood transfusions and the subsequent risk of hematologic malignancies

BACKGROUND

Blood transfusions are associated with viral transmission and immunomodulation, perhaps increasing subsequent risk of hematologic malignancies (HMs). Prior studies of transfusion recipients have lacked details on specific HM subtypes.

STUDY DESIGN AND METHODS

Risk of HM after blood transfusion was evaluated in a US population-based case-control study (77,488 elderly HM cases identified through cancer registries, 154,509 controls). Transfusions were identified using linked Medicare hospitalization claims. Polytomous logistic regression was used to calculate odds ratios (ORs) associating transfusion and HM subtypes by features suggestive of a causal relationship.

RESULTS

A history of transfusion was present in 7.9% of HM cases versus 5.9% of controls. Associations for most HM subtypes suggested reverse causality: ORs were elevated only during the shortest latency periods; ORs for unspecified anemia and gastrointestinal bleeding, which may be related to undiagnosed HM, were stronger than for surgeries, which are unlikely to be related to HM; and/or there was no dose response. In contrast, risk for lymphoplasmacytic lymphoma (1397 cases) was elevated at long latency (OR, 1.56 at 10+ years after transfusion), after transfusions related to surgeries (OR, 1.22-1.47), and in a dose-response relationship with number of transfusion-related hospitalizations (OR, 1.53 with one hospitalization; OR, 1.80 with two or more hospitalizations, p trend < 0.0001). Risk for marginal zone lymphoma (1915 cases) was also elevated at 10+ years after transfusion (OR, 1.80).

CONCLUSION

Consistent with prior studies, blood transfusions did not increase risk of most HM subtypes. Patterns of elevated risk for lymphoplasmacytic and marginal zone lymphomas suggest an etiologic role for transfusion.

Researching genetic versus nongenetic determinants of disease: a comparison and proposed unification

Research standards deviate in genetic versus nongenetic epidemiology. Besides some immutable differences, such as the correlation pattern between variables, these divergent research standards can converge considerably. Current research designs that dissociate genetic and nongenetic measurements are reaching their limits. Studies are needed that massively measure genotypes, nongenetic exposures, and outcomes concurrently.

Duration of red blood cell storage and survival of transfused patients (CME)

BACKGROUND

Disquieting reports of increased complication and death rates after transfusions of red blood cells (RBCs) stored for more than 14 days prompted us to perform an observational retrospective cohort study of mortality in relation to storage time.

STUDY DESIGN AND METHODS

We conducted a cohort study utilizing data on all recipients of at least one RBC transfusion in Sweden and Denmark between 1995 and 2002, as recorded in the Scandinavian Donations and Transfusions (SCANDAT) database. Relative risks of death in relation to storage time were estimated using Cox regression, adjusted for several possible confounding factors.

RESULTS

After various exclusions, 404,959 transfusion episodes remained for analysis. The 7-day risk of death was similar in all exposure groups, but a tendency for a higher risk emerged among recipients of blood stored for 30 to 42 days (hazard ratio, 1.05; 95% confidence interval [CI], 0.97-1.12), compared to recipients of blood stored for 10 to 19 days. With 2-year follow-up, this excess remained at the same level (hazard ratio, 1.05; 95% CI, 1.02-1.08). No dose-response pattern was revealed and no differential effect was seen when the analyses were restricted to recipients of leukoreduced units only.

CONCLUSION

Although a small excess mortality was noted in recipients of the oldest RBCs, the risk pattern was more consistent with weak confounding than with an effect of the momentary exposure to stored RBCs. It seems, thus, that any excess mortality conferred by older RBCs in the combined Swedish and Danish transfusion recipient population is likely less than 5%, which is considerably smaller than in the hitherto largest investigation.

A proposed method to adjust for selection bias in cohort studies

Selection bias is a concern in cohort studies in which selection into the cohort is related to the studied outcome. An example is chronic infection with hepatitis C virus, where the initial infection may be asymptomatic for decades. This problem leads to selection of more severely ill individuals into registers of such infections. Cohort studies often adjust for this bias by introducing a time window between entry into the cohort and entry into the study. This paper describes and assesses a novel method to improve adjustment for this type of selection bias. The size of the time window is decided by calculating a standardized incidence ratio as a continuous function of the size of the time window. The resulting graph is used to decide on an appropriate window size. The method is evaluated by using the Swedish register of hepatitis C virus infections for 1990-2006. The complications studied were non-Hodgkin lymphoma and liver cancer. Selection bias differed for the studied outcomes, and a time window of a minimum of 2 months and 12 months, respectively, was judged to be appropriate. The novel method may have advantages compared with an interval-based method, especially in cohort studies with small numbers of events.

Blood transfusion exposure in Denmark and Sweden

BACKGROUND

Although essential for the evaluation of blood transfusion safety, the prevalence of blood transfusion in the general population is not presently known. This study estimated the exposure to blood transfusion in the general Scandinavian population.

STUDY DESIGN AND METHODS

Population-based registry data of more than 600,000 transfusion recipients and general population data from 2000 to 2002 in Denmark and 1996 to 2002 in Sweden were reviewed. Outcome measures were the unit exposure rate, the 1-year period prevalence, the incidence rate, and the prevalence of exposure to blood transfusion.

RESULTS

The unit exposure rate was 71.9 per 1000 population per year in Denmark and 60.9 in Sweden, corresponding to 29 percent more blood units being transfused in Denmark than in Sweden. The 1-year period prevalence was 8.8 and the incidence rate was 7.2 per 1000 population per year in Denmark, being 37 and 25 percent higher than in Sweden, respectively. The prevalences of blood transfusion in Danish males at 20, 40, 60, and 80 years of age were 1.9, 3.1, 7.6, and 18.1 percent, respectively. In Danish females, the corresponding prevalences were 1.6, 5.9, 11.1, and 20.5 percent. A similar but slightly lower prevalence was found in Sweden.

CONCLUSION

Exposure to blood transfusion is frequent in Denmark and Sweden. At age 80 years, approximately one in five persons in the general population had received blood at least once.

Blood transfusions, thrombosis, and mortality in hospitalized patients with cancer

BACKGROUND

Anemia is frequent in patients with cancer, but there are concerns regarding treatment with erythropoiesis-stimulating agents. Blood transfusions are commonly used as an alternative, but with little data regarding outcomes.

METHODS

In a retrospective cohort study, we investigated the associations between transfusions and venous thromboembolism, arterial thromboembolism, and mortality in hospitalized patients with cancer using the discharge database of the University HealthSystem Consortium, which included 504 208 hospitalizations of patients with cancer between 1995 and 2003 at 60 US medical centers.

RESULTS

Of the patients included, 70 542 (14.0%) received at least 1 red blood cell (RBC) transfusion and 15 237 (3.0%) received at least 1 platelet transfusion. Of patients receiving RBC transfusions, 7.2% developed venous thromboembolism and 5.2% developed arterial thromboembolism, and this was significantly greater than the rates of 3.8% and 3.1%, respectively, for the remaining study population (P < .001). In multivariate analysis, RBC transfusion (odds ratio [OR], 1.60; 95% confidence interval [CI], 1.53-1.67) and platelet transfusion (1.20; 1.11-1.29) were independently associated with an increased risk of venous thromboembolism. Both RBC transfusion (OR, 1.53; 95% CI, 1.46-1.61) and platelet transfusion (1.55; 1.40-1.71) were also associated with arterial thromboembolism (P < .001 for each). Transfusions were also associated with an increased risk of in-hospital mortality (RBCs: OR, 1.34; 95% CI, 1.29-1.38; platelets: 2.40; 2.27-2.52; P < .001).

CONCLUSIONS

Both RBC and platelet transfusions are associated with increased risks of venous and arterial thrombotic events and mortality in hospitalized patients with cancer. Further investigation is necessary to determine whether this relationship is causal.