The Role of Environmental Factors in the Etiology of Lymphoma

Phytostilbenes in lymphoma: Focuses on the mechanistic and clinical prospects of resveratrol, pterostilbene, piceatannol, and pinosylvin

Lymphoma is a cancer affecting the lymphatic system that fights infections and diseases. In addition to surgery, radiotherapy, and chemotherapy, novel approaches have recently been investigated, such as phytostilbenes in treating lymphoma. Phytostilbenes are natural compounds present in various plants and have been shown to have different therapeutic effects, including anticancer properties. Resveratrol is a main phytostilbene with various derivates followed by pterostilbene and piceatannol. Studies have revealed that phytostilbenes can suppress the growth and proliferation of lymphoma cells by inducing apoptosis and inhibiting specific enzyme activity in cancer cell survival. The compounds also have antiinflammatory effects contributing to reducing lymphoma-associated inflammation. Additionally, phytostilbenes have been shown to increase the immune system's ability to fight cancer cells by activating immune cells (T-cells and natural killer cells). This review investigates the potential therapeutic effects of phytostilbenes, including resveratrol, pterostilbene, piceatannol, and pinosylvin, against lymphoma.

Second malignant neoplasms in lymphomas, secondary lymphomas and lymphomas in metabolic disorders/diseases

With inconsistent findings, evidence has been obtained in recent years that metabolic disorders are closely associated with the development of lymphomas. Studies and multiple analyses have been published also indicating that some solid tumor survivors develop a secondary lymphoma, whereas some lymphoma survivors subsequently develop a second malignant neoplasm (SMN), particularly solid tumors. An interaction between the multiple etiologic factors such as genetic factors and late effects of cancer therapy may play an important role contributing to the carcinogenesis in patients with metabolic diseases or with a primary cancer. In this review, we summarize the current knowledge of the multiple etiologic factors for lymphomagenesis, focusing on the SMN in lymphoma, secondary lymphomas in primary cancers, and the lymphomas associated to metabolic disorders/diseases, which have been received less attention previously. Further, we also review the data of coexistence of lymphomas and hepatocellular carcinoma (HCC) in patients with infection of hepatitis C virus and hepatitis B virus.

Epigenetic Alteration of the Cancer-Related Gene TGFBI in B Cells Infected with Epstein-Barr Virus and Exposed to Aflatoxin B1: Potential Role in Burkitt Lymphoma Development

Burkitt lymphoma (BL) is a malignant B cell neoplasm that accounts for almost half of pediatric cancers in sub-Saharan African countries. Although the BL endemic prevalence is attributable to the combination of Epstein-Barr virus (EBV) infection with malaria and environmental carcinogens exposure, such as the food contaminant aflatoxin B1 (AFB1), the molecular determinants underlying the pathogenesis are not fully understood. Consistent with the role of epigenetic mechanisms at the interface between the genome and environment, AFB1 and EBV impact the methylome of respectively leukocytes and B cells specifically. Here, we conducted a thorough investigation of common epigenomic changes following EBV or AFB1 exposure in B cells. Genome-wide DNA methylation profiling identified an EBV-AFB1 common signature within the TGFBI locus, which encodes for a putative tumor suppressor often altered in cancer. Subsequent mechanistic analyses confirmed a DNA-methylation-dependent transcriptional silencing of TGFBI involving the recruitment of DNMT1 methyltransferase that is associated with an activation of the NF-κB pathway. Our results reveal a potential common mechanism of B cell transformation shared by the main risk factors of endemic BL (EBV and AFB1), suggesting a key determinant of disease that could allow the development of more efficient targeted therapeutic strategies.

Two Cases of Pelvic Diffuse Large B-Cell Lymphoma

Primary diffuse large B-cell lymphoma presenting as an extranodal site in the pelvis is rare and can mimic a gynecological malignancy. Although management for diffuse large B-cell lymphoma is standardized and curative, prognosis depends on timely diagnosis and therapy. Diagnosis can be challenging as patients lack classical symptoms of fever, night sweats, weight loss, and lymphadenopathy associated with lymphoma. A multidisciplinary approach is recommended to diagnose and treat judiciously. In this article, we present cases of 2 females who presented with pelvic masses with initial suspicion of a gynecological malignancy but were ultimately diagnosed as diffuse large B-cell lymphoma of the pelvis and managed accordingly.

Diffuse Large B-Cell Lymphoma Discovered following Total Knee Arthroplasty: A Case Report and Literature Review

Total knee arthroplasty is performed routinely for osteoarthritis of the knee joint. We report a case of high-grade diffuse large B-cell lymphoma as an unexpected diagnosis after histopathological examination of unusual-looking synovium during total knee arthroplasty in a 68-year-old patient without any systemic symptoms.

Primary Synovial Diffuse Large B-Cell Lymphoma Presenting as Loosening of Prosthetic Joint: A Case Report and Review of Literature

Primary synovial diffuse B-cell lymphoma is a rare clinical condition. The condition presents primarily with localized joint symptoms such as swelling, pain and reduced range of motion. It may or may not be associated with lymphadenopathy, hepatosplenomegaly or B-type constitutional symptoms. We report a case of a 74-year-old woman who presented with persistent left knee pain and swelling after left knee replacement secondary to osteoarthritis. There was a concern for mechanical loosening of internal left knee prosthetic joint. On revision surgery (14 weeks after the initial surgery), hypertrophied synovium with areas of fibrotic scars, necrotic tissue and dark colored masses was resected. She was found to have diffuse large B-cell lymphoma (DLBCL) after histological analysis. In cases with persistent joint symptoms or postoperative complications, arthroscopy or arthrotomy should be considered and any atypical appearing tissue should be sent for histopathological analysis.

Erythema Gyratum Repens Associated With Diffuse B-cell Lymphoma-Report of A Rare Case

Erythema gyratum repens (EGR) is a rare paraneoplastic dermatosis known to be associated with internal malignancy. Herein, we report a case of EGR with diffuse large B-cell lymphoma (DLBCL) in a young farmer who presented with generalized massive lymphadenopathy and wood-grain pattern dermatosis. Lymph node biopsy with immunohistochemistry established the diagnosis of DLBCL. He was managed by the oncologist with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) regimen which alleviated his symptoms considerably after completion of three cycles and was under follow-up.

The effect of biological heterogeneity on R-CHOP treatment outcome in diffuse large B-cell lymphoma across five international regions

Addressing the global burden of cancer, understanding its diverse biology, and promoting appropriate prevention and treatment strategies around the world has become a priority for the United Nations and International Atomic Energy Agency (IAEA), the WHO, and International Agency for Research on Cancer (IARC). The IAEA sponsored an international prospective cohort study to better understand biology, treatment response, and outcomes of diffuse large B-cell lymphoma (DLBCL) in low and middle-income countries across five UN-defined geographical regions. We report an analysis of biological variation in DLBCL across seven ethnic and environmentally diverse populations. In this cohort of 136 patients treated to a common protocol, we demonstrate significant biological differences between countries, characterized by a validated prognostic gene expression score (p < .0001), but International Prognostic Index (IPI)-adjusted survivals in all participating countries were similar. We conclude that DLBCL treatment outcomes in these populations can be benchmarked to international standards, despite biological heterogeneity.

Cancer incidence in urban Shanghai, 1973-2010: an updated trend and age-period-cohort effects

Background

To provide a comprehensive overview of temporal trends in cancer incidence during 1973–2010 in urban Shanghai.

Methods

The estimated annual percent changes (EAPCs) for the whole period and for the time segments in age-standardized incidence rates (ASR) were evaluated with Joinpoint analysis. Age-period-cohort (APC) models were modeled to examine the effects of age, period and birth cohort on cancer incidence.

Results

The overall ASR decreased slightly and significantly in males (EAPC of −0.41) but increased significantly in females (EAPC of 0.57) during 1973–2010 in urban Shanghai. The incidence trend was not linear and varied by time segments. During the most recent 10 years (2001–2010), the ASR in males decreased by 1.65 % per year and stabilized in females. Incidence rates continued to decline during 1973–2010 for esophagus, stomach, and liver cancer in both sexes, as well as male lung cancer and cervix cancer. It should be noted that it was the first time to document a significant decline in lung cancer incidence among males during 1973–2010 with EAPC of −0.58 %, and a notable upward for cervix cancer since 1996 with EAPC of 8.94 %. Unfavorable trends in incidence were observed for the most common cancer sites in the 38 years period: colorectum, gallbladder & biliary tract, pancreas, kidney, bladder, brain & central nervous system (CNS), thyroid, non-Hodgkin’s lymphoma (NHL), prostate, female breast, corpus uteri, and ovary. APC analysis showed age, period and birth cohort yielded different effects by cancer sites.

Conclusions

The observed trends primarily reflect dramatic changes in socioeconomic development and lifestyles in urban Shanghai over the past four decades.

Characteristics and prognostic factors for head and neck non-Hodgkin's lymphoma in Chinese patients

BACKGROUND AND OBJECTIVES

The head and neck region is the second most frequent anatomical site of extranodal lymphomas. These tumours affect many individuals worldwide, justifying epidemiological studies in different countries. This study evaluated the characteristics, treatments and prognostic factors for non-Hodgkin's lymphoma of the head and neck in Chinese patients.

METHOD

The clinical manifestations, clinicopathological characteristics, multidisciplinary treatment and prognostic factors for 102 patients with extranodal non-Hodgkin's lymphoma of the head and neck were analysed retrospectively.

RESULT

The tonsil was the most commonly involved primary site, followed by the nasal cavity. The most common histological subtype was diffuse large B-cell lymphoma, followed by natural killer T-cell lymphoma. Patients receiving a combination of rituximab and chemotherapy did better than those receiving chemotherapy alone. Prognosis was significantly associated with both International Prognostic Index and histological subtype; the former was especially strongly associated with poor survival.

CONCLUSION

In this group of Chinese patients, diffuse large B-cell lymphoma was the most common pathological subtype, but the incidence of T-cell lymphomas was higher than that reported in the USA. Combined rituximab and chemotherapy led to better outcomes than chemotherapy alone. Prognosis depended on both International Prognostic Index and histological subtype.

Patients with activated B-cell like diffuse large B-cell lymphoma in high and low infectious disease areas have different inflammatory gene signatures

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease with an association with inflammation and viral infections. We hypothesize that environmental factors may be involved in the pathogenesis of DLBCL. In this study, we compared gene expression profiles of lymph node tissues from patients with DLBCL from two different geographical areas with diverse environmental exposures. Specimens from Egyptian and Swedish patients with DLBCL as well as controls were studied. Gene expression analysis using microarray and quantitative polymerase chain reaction demonstrated significantly higher expression of signal transducer and activator of transcription 3 (STAT3) in Swedish as compared to Egyptian patients and control materials from both countries. This was confirmed at protein level using confocal microscopy. The receptor tyrosine kinase ROR1, a "survival factor" for malignant cells, was overexpressed and significantly related to the STAT3 expression pattern. The difference in the expression of genes involved in inflammatory responses and in the tumorigenic process of DLBCL might relate to infectious agents and/or other environmental exposures.

Aggressive sinonasal natural killer/T-cell lymphoma mimicking refractory sinusitis in a 4-year-old boy

Pediatric patients with nasal symptoms are common, and most of them usually have inflammatory diseases, such as sinusitis, chronic rhinitis, nasal polyp, or adenotonsillar hypertrophy. Rarely, however, these inflammatory symptoms may be associated with more sinister pathology. Recently, we experienced a case of a 4-year-old boy with sinonasal natural killer (NK)/T-cell lymphoma whose initial symptoms were of nasal obstruction and mucopurulent nasal discharge.

Epidemiologic overview of malignant lymphoma

Malignant lymphoma encompasses a wide variety of distinct disease entities. It is generally more common in developed countries and less common in developing countries. The East Asia region has one of the lowest incidence rates of malignant lymphoma. The incidence of malignant lymphoma around the world has been increasing at a rate of 3-4% over the last 4 decades, while some stabilization has been observed in developed countries in recent years. The reasons behind this lymphoma epidemic are poorly understood, although improving diagnostic accuracy, the recent AIDS epidemic, an aging world population and the increasing adoption of cancer-causing behaviors are suggested as contributing factors. Etiologies of malignant lymphoma include infectious agents, immunodeficiency, autoimmune disease, exposure to certain organic chemicals, and pharmaceuticals. The distribution of many subtypes exhibit marked geographic variations. Compared to the West, T/natural killer (NK) cell lymphomas (T/NK-cell lymphoma) and extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) are relatively more common, whereas other B-cell lymphomas, particularly follicular lymphoma and chronic lymphocytic leukemia/small lymphocytic lymphoma, are less common in Asia. Some subtypes of T/NK-cell lymphomas defined by Epstein-Barr virus association are predominantly Asian diseases, if not exclusively so. Both ethnic and environmental factors play roles in such diversity. In this review, we discuss the geographic distribution and etiology of malignant lymphoma, as well as the trend.

Pesticide use, immunologic conditions, and risk of non-Hodgkin lymphoma in Canadian men in six provinces

Pesticide exposures and immune suppression have been independently associated with the risk of non-Hodgkin lymphoma (NHL), but their joint effect has not been well explored. Data from a case-control study of men from six Canadian provinces were used to evaluate the potential effect modification of asthma, allergies, or asthma and allergies and hay fever combined on NHL risk from use of: (i) any pesticide; (ii) any organochlorine insecticide; (iii) any organophosphate insecticide; (iv) any phenoxy herbicide; (v) selected individual pesticides [1,1'-(2,2,2-trichloroethylidene)bis[4-chlorobenzene]; 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT), malathion, (4-chloro-2-methylphenoxy)acetic acid (MCPA), mecoprop, and (2,4-dichlorophenoxy)acetic acid (2,4-D); and (vi) from the number of potentially carcinogenic pesticides. Incident NHL cases (n = 513) diagnosed between 1991 and 1994 were recruited from provincial cancer registries and hospitalization records and compared to 1,506 controls. A stratified analysis was conducted to calculate odds ratios (ORs) adjusted for age, province, proxy respondent, and diesel oil exposure. Subjects with asthma, allergies, or hay fever had non-significantly elevated risks of NHL associated with use of MCPA (OR = 2.67, 95% confidence interval [CI]: 0.90-7.93) compared to subjects without any of these conditions (OR = 0.81, 95% CI: 0.39-1.70). Conversely, those with asthma, allergies, or hay fever who reported use of malathion had lower risks of NHL (OR = 1.25, 95% CI: 0.69-2.26) versus subjects with none of these conditions (OR = 2.44, 95% CI: 1.65-3.61). Similar effects were observed for asthma and allergies evaluated individually. Although there were some leads regarding effect modification by these immunologic conditions on the association between pesticide use and NHL, small numbers, measurement error and possible recall bias limit interpretation of these results.

Exposure to animals and increased risk of marginal zone B-cell lymphomas of the ocular adnexae

BACKGROUND

Ocular adnexal marginal zone B-cell lymphoma (OAMZL) has been associated with Chlamydophila psittaci, an infection that may be transmitted by carrier animals. However, it is still unclear whether exposure to animals affects the risk of OAMZL in comparison with other lymphoma histotypes. We therefore investigated the role of professional and/or domestic exposures to animals in the occurrence of OAMZL, as compared with other types of lymphoma.

METHODS

A hospital-based case-control study was carried out on 43 consecutive OAMZL patients (cases) and 87 consecutive patients with nodal non-Hodgkin's lymphomas (NHLs; controls). Multiple logistic regression (MLR) odds ratios (ORs), and 95% confidence intervals (CIs) were used to estimate the association between exposures to animals and OAMZL risk.

RESULTS

A higher proportion of cases reported a lifetime exposure to household animals (79.1% vs 64.4% among controls), with a non-statistical significant MLR-OR of 2.18 (95% CI: 0.85-5.62). The OAMZL cases more frequently reported a history of occupation in breeding and/or slaughtering than controls (34.9% vs 6.9%), with an overall increased risk of 7.69 (95%CI: 2.65-22.34).

CONCLUSION

These results indicate that, compared with nodal NHLs, the risk of OAMZL is markedly increased by contact with animals, particularly by occupational exposures.

Growing tumor vessels: more than one way to skin a cat - implications for angiogenesis targeted cancer therapies

The establishment of a functional, integrated vascular system is instrumental for tissue growth and homeostasis. Without blood vessels no adequate nutrition and oxygen would be provided to cells, nor could the undesired waste products be efficiently removed. Blood vessels constitute therefore one of the largest and most complex body network whose assembly depends on the precise balance of growth factors acting in a complementary and coordinated manner with cells of several identities. However, the vessels that are crucial for life can also foster death, given their involvement in cancer progression towards malignancy and metastasis. Targeting tumor vasculature has thus arisen as an appealing anti-cancer therapeutic approach. Since the milestone achievements that vascular endothelial growth factor (VEGF) blockade suppressed angiogenesis and tumor growth in mice and prolonged the survival of cancer patients when administered in combination with chemotherapy, the clinical development of anti-VEGF(R) drugs has accelerated remarkably. FDA has approved the use of bevacizumab - a humanized monoclonal antibody against VEGF - in colorectal, lung and metastatic breast cancers in combination with standard chemotherapy. Additional broad-spectrum VEGF receptor tyrosine kinase inhibitors, such as sunitinib and sorafenib, are used in monotherapy for metastatic renal carcinoma, while sunitinib is also approved for imatinib resistant gastrointestinal stromal tumors and sorafenib for advanced stage hepatocellular carcinoma. Nevertheless, the survival benefit offered by VEGF(R) blockers, either as single agents or in combination with chemotherapy, is calculated merely in the order of months. Posterior studies in preclinical models have reported that despite reducing primary tumor growth, the inhibition of VEGF increased tumor invasiveness and metastasis. The clinical implications of these findings urge the need to reconcile these conflicting results. Anti-angiogenic therapy represents a significant step forth in cancer therapy and in our understanding of cancer biology, but it is also clear that we need to learn how to use it. What is the biological consequence of VEGF-blockade? Does VEGF inhibition starve the tumor to death - as initially postulated - or does it rather foster malignancy? Can anti-VEGF(R) therapy favor tumor vessel formation by VEGF-independent means? Tumors are very diverse and plastic entities, able to adapt to the harshest conditions; this is also reflected by the tumor vasculature. Lessons from the bench to the bedside and vice versa have taught us that the diversity of signals underlying tumor vessel growth will likely be responsive (or resistant) to distinct therapeutic approaches. In this review, we propose a reflection of the different strategies tumors use to grow blood vessels and how these can have impact on the (un)success of current anti-angiogenic therapies.

Age-period-cohort modelling of non-Hodgkin's lymphoma incidence in a French region: a period effect compatible with an environmental exposure

BACKGROUND

The incidence of non-Hodgkin's lymphoma (NHL) has risen steadily during the last few decades in all geographic regions covered by cancer registration for reasons that remain unknown. The aims of this study were to assess the relative contributions of age, period and cohort effects to NHL incidence patterns and therefore to provide clues to explain the increasing incidence.

METHODS

Population and NHL incidence data were provided for the Doubs region (France) during the 1980-2005 period. NHL counts and person-years were tabulated into one-year classes by age (from 20 to 89) and calendar time period. Age-period-cohort models with parametric smooth functions (natural splines) were fitted to the data by assuming a Poisson distribution for the observed number of NHL cases.

RESULTS

The age-standardised incidence rate increased from 4.7 in 1980 to 11.9 per 100,000 person-years at risk in 1992 (corresponding to a 2.5-fold increase) and stabilised afterwards (11.1 per 100,000 in 2005). Age effects showed a steadily increasing slope up to the age of 80 and levelled off for older ages. Large period curvature effects, both adjusted for cohort effects and non-adjusted (p < 10-4 and p < 10-5, respectively), showed departure from linear periodic trends; period effects jumped markedly in 1983 and stabilised in 1992 after a 2.4-fold increase (compared to the 1980 period). In both the age-period-cohort model and the age-cohort model, cohort curvature effects were not statistically significant (p = 0.46 and p = 0.08, respectively).

CONCLUSIONS

The increased NHL incidence in the Doubs region is mostly dependent on factors associated with age and calendar periods instead of cohorts. We found evidence for a levelling off in both incidence rates and period effects beginning in 1992. It is unlikely that the changes in classification (which occurred after 1995) and the improvements of diagnostic accuracy could largely account for the 1983-1992 period-effect increase, giving way to an increased exposure to widely distributed risk factors including persistent organic pollutants and pesticides. Continued NHL incidence and careful analysis of period effects are of utmost importance to elucidate the enigmatic epidemiology of NHL.

Imaging of head and neck neoplasms in children

The characteristic imaging appearance for a variety of common and/or important pediatric head and neck tumors will be described in this review. These include benign masses such as hemangioma, teratoma, nerve sheath tumors, juvenile nasopharyngeal angiofibroma and malignant masses such as rhabdomyosarcoma, lymphoma, carcinoma and retinoblastoma. This review focuses primarily on soft tissue tumors.

EPCs and pathological angiogenesis: when good cells go bad

Bone-marrow-derived endothelial progenitor cells (EPCs) contribute to angiogenesis-mediated pathological neovascularization, and recent studies have begun to recognize the biological significance of this contribution. This review will discuss the ability of EPCs to contribute to neovascularization in both physiological and pathological conditions. Circulating EPCs were originally identified in 1997 by Asahara as CD34(+) VEGFR2(+) mononuclear cells. These cells differentiated into an endothelial phenotype, expressed endothelial markers, and incorporated into neovessels at sites of ischemia (Asahara et al., 1997). EPCs provide both instructive (release of pro-angiogenic cytokines) and structural (vessel incorporation and stabilization) functions that contribute to the initiation of neo-angiogenesis. EPC populations can be characterized based on surface markers of freshly isolated cells, or they can be described by their in vitro characteristics once placed in culture. However, a major stumbling block to progress in the field has been the lack of consensus among investigators as to the optimal characterization of EPCs. This review intends to address the role of both EPC classes and evaluate how they interact in the setting of pathological angiogenesis. Since the EPCs may be responsible for turning on the "angiogenic switch," strategies have been employed to keep this switch in the "off" position for diseases like cancer, retinopathy, and wet AMD. The expectation is that EPCs will evolve into clinically useful prognostic and predictive tools in cancer and in ocular diseases associated with pathological neovascularization and that targeting this cell type is a key to successful management of patients suffering from diseases associated with pathological neovascularization.

Diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) remains a curable lymphoma, with improved outcome resulting in large part from the incorporation of rituximab in standard regimens. The disease is heterogeneous clinically, morphologically, and molecularly. Recent insights into the molecular heterogeneity of DLBCL are beginning to yield novel therapeutics with significant promise for key subsets of patients. Although cyclophosphamide, hydroxydaunorubicin, vincristine, and prednisone chemotherapy with rituximab remains a standard therapeutic approach for most patients who have DLBCL, it is anticipated that novel agents will be included in treatment regimens for many patients in the near future.