Chlamydia psittaci in ocular adnexa MALT lymphoma: a possible role in lymphomagenesis and a different geographical distribution

Utility of PD-1, PD-L1, and IDO-1 Stains in Ocular Extranodal Marginal Zone Lymphoma (MZL) and Diffuse Large B-cell Lymphoma (DLBCL)

Extranodal marginal zone lymphoma (EMZL) is the most common subtype of ocular lymphomas. Diffuse large B-cell lymphoma (DLBCL) and EMZL with large-cell transformation present diagnostic challenges. Radiotherapy is the standard treatment for ocular lymphomas, but complications and relapse are common. Diagnostic utility in challenging cases, as well as treatment options using immune checkpoint inhibitors, are unclear in ocular lymphomas. We herein investigated the PD-1, PD-L1, and IDO1 staining patterns in 20 cases of ocular lymphomas, including EMZL (n=14), EMZL with increased large cells (n=2), and DLBCL (n=4). PD-1, PD-L1, and IDO1 staining was not detected in lymphoma cells in any cases but was observed within the tumor microenvironment in all cases. Positivity for PD-1, PD-L1, and IDO1 in inflammatory cells was seen either intratumorally or peritumorally. In all 6 cases with significantly more large B cells, the density of PD-1, PD-L1, and IDO1 expression in the tumor microenvironment was higher than that of the remaining 14 cases without large B cells (P-value<0.0001), whereas other clinicopathologic features showed no statistical correlation. Increased expression of PD-1, PD-L1, and IDO1 in the inflammatory milieu in cases with large cells may provide diagnostic utility in small biopsies as well as therapeutic potential.

Declining incidence and improving survival of ocular and orbital lymphomas in the US between 1995 and 2018

This epidemiological study examined ocular and orbital lymphomas in the United States from 1995 to 2018, using data from the North American Association of Central Cancer Registries database of 87,543 patients with ocular and adnexal malignancies. We identified 17,878 patients (20.4%) with ocular and orbital lymphomas, with an age-standardized incidence rate (ASIR) of 2.6 persons per million (ppm). The incidence was the highest in the orbit (ASIR = 1.24), followed by the conjunctiva (ASIR = 0.57). Non-Hodgkin B-cell lymphoma was the most prevalent subtype (85.4%), particularly marginal-zone lymphoma (45.7%). Racial disparities were noted, with Asia-Pacific Islanders showing the highest incidence (orbit, 1.3 ppm). The incidence increased significantly from 1995 to 2003 (Average Percent Change, APC = 2.1%) but declined thereafter until 2018 (APC = - 0.7%). 5-year relative survival (RS) rates varied, with the highest rate for conjunctival lymphoma (100%) and the lowest for intraocular lymphoma (70.6%). Survival rates have generally improved, with an annual increase in the 5-year RS of 0.45%. This study highlights the changing epidemiological landscape, pointing to initial increases and subsequent decreases in incidence until 2003, with survival improvements likely due to advancements in treatment. These findings underscore the need for further research to investigate the root causes of these shifts and the declining incidence of ocular lymphoma.

Ocular lymphoma: overcoming a diagnostic challenge with an endoscopic sinus approach

BACKGROUND

Ocular lymphomas are rare, indolent tumours that pose a diagnostic challenge. Patients may be asymptomatic or present with symptoms of increased orbital mass. An index of suspicion is required alongside an understanding of the diagnostics and staging required to facilitate expedited multi-disciplinary work-up and management.

METHODS

A comprehensive literature review was performed. We present a series of three cases, each presenting their own diagnostic challenge.

RESULTS

Although ocular lymphomas are notoriously difficult to diagnose histologically, our case series show procurement of a diagnostic histological sample using an image-guided endoscopic sinus approach.

CONCLUSIONS

Although not typically involved in the diagnosis or management, the otolaryngologist may encounter ocular lymphoma masquerading as sinus disease or with disseminated disease at other sites in the head and neck. Endoscopic sinus surgery is considered a safe, effective approach for achieving a histological diagnosis in these cases.

Comprehensive analysis of orbital lymphoma in a Turkish cohort: clinical characteristics, histological subtypes, treatment modalities, prognostic factors, and implications for management

The study analysed the clinical characteristics, treatment approaches, and survival outcomes of 97 consecutive patients with orbital lymphoma (OL) over a 25-year period at. The median age of the patients was 57.6 years, and 59.8% (n = 58) were male. Marginal zone lymphoma constitutes the most prevalent subtype, accounting for 67% of cases, whereas other common subtypes include diffuse large B-cell lymphoma, follicular lymphoma, mantle cell lymphoma, Burkitt lymphoma, and T-cell lymphomas. Unilateral involvement was observed in the majority of cases (72.3%). Common clinical presentations included mass (30.9%), swelling (26.8%), and epiphora (11.3%). Of the patients, 7.2% received rituximab alone, 14.4% received radiotherapy alone, 48.5% received chemotherapy, 27.8% received radiotherapy plus rituximab, 22.7% received radiotherapy plus chemotherapy, and 5.2% underwent surgery as the first-line treatment. During a median follow-up of 4.3 years, 15.5% of patients experienced relapse or disease progression. The 5-year and 10-year progression-free survival rates were 84.1% and 79.1%, respectively. This study contributes to our understanding of OLs and provides a foundation for further investigations in this field. Male gender, presence of B symptoms, advanced stage, secondary orbital lymphoma, aggressive histological subtype, and elevated serum lactate dehydrogenase levels were associated with poorer (either inferior or worse) progression-free survival.

Feasibility of oral doxycycline as first-line therapy for conjunctival mucosa-associated lymphoid tissue lymphoma

OBJECTIVES

To investigate the long-term outcomes of oral doxycycline as first-line treatment in patients with conjunctival extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma).

METHODS

In this case series, the medical records of 67 patients with conjunctival MALT lymphoma who received doxycycline as their primary treatment and were followed up for at least 5 years were retrospectively reviewed. Progression-free survival (PFS) was analysed at 3, 5, and 10 years after the initial doxycycline treatment. A Cox proportional hazards model was used to assess the independent risk factors for progression.

RESULTS

After the initial treatment, 25 patients (37.3%) achieved a complete response, 8 patients (11.9%) achieved a partial response, 30 patients (44.8%) showed stable disease, and 4 patients (6.0%) showed disease progression. The median PFS in all patients was 168 months, and the 3-, 5- and 10-year PFS rates for all patients were 70%, 65%, and 62%, respectively. No further progression was observed 6 years after the initial doxycycline treatment. Younger age and TNM stage T1c were significant risk factors for the time to progression in the multivariate Cox regression analysis (p < 0.05). Additional doxycycline (>2 cycles) showed no benefit. There were no serious adverse events associated with doxycycline therapy, and most patients were successfully salvaged by second-line treatments, including radiotherapy and chemotherapy.

CONCLUSION

In this case series, oral doxycycline treatment yielded acceptable long-term PFS with minimal complications. Especially in patients with stage T1a or T1b conjunctival MALT lymphoma, first-line doxycycline treatment could be considered under close monitoring for at least 6 years.

Management of Marginal Zone Lymphoma: A Canadian Perspective

Marginal zone lymphomas (MZL) are a rare, heterogenous group of lymphomas, accounting for 5-17% of indolent non-Hodgkin lymphomas in the western world. They can be further divided into three subtypes: extranodal MZL, splenic MZL, and nodal MZL. These subtypes differ in clinical presentation and behavior, which influences how they are managed. There is currently no standard of care for the treatment of MZL, owing to the difficulty in conducting phase 3 randomized trials in MZL, and the fact that there are limited data on the efficacy of therapy in individual subtypes. Treatment practices are thus largely borrowed from other indolent lymphomas and are based on patient and disease characteristics, as well as access to therapy. This review summarizes the Canadian treatment landscape for MZL and how these therapies may be sequenced in practice.

First-line antibiotic treatment in patients with localized extragastric mucosa-associated lymphoid tissue lymphoma

Between January 2010 and December 2015, we enrolled 28 patients with stage IEI/IIE1 extragastric mucosa-associated lymphoid tissue (MALT) lymphoma who received first-line antibiotic treatment, after informing them about the pros and cons of alternative therapies. In addition, during the same period, 64 patients with stage IE/IIE1 disease who received conventional treatment were selected as the control group. The most common primary sites were the ocular adnexal area (17 cases), followed by the salivary glands (four cases), pulmonary (three cases), and thyroid, trachea, larynx, and colon region (one case each). First-line antibiotic treatment resulted in an overall response rate of 57.1%: 12 patients achieved complete remission (CR), while four achieved partial remission (antibiotic-responsive tumors). Monoclonal gammopathy was significantly prevalent in antibiotic-unresponsive tumors than in antibiotic-responsive tumors (50.0% [6/12] vs. 12.5% [2/16], p = 0.044). After a median follow-up of 7 years, all patients with CR remained lymphoma-free, with 7-year event-free survival (EFS) and overall survival (OS) rates of 62.7% and 96.4%, respectively. The 7-year EFS and OS rates of patients who received conventional treatments were 73.1% and 91.1%, respectively. Compared with that noted in patients who received conventional treatment, antibiotic treatment was effective in some patients with localized extragastric MALT lymphoma.

Clinicopathologic Characteristics Associated with Prognosis in Ocular Extranodal Marginal Zone B Cell Lymphoma

Background and Objectives: Extranodal marginal zone lymphoma of the mucosa-associated lymphoid tissue (MALT) type is the most common subtype of the ocular adnexal lymphoma. Despite its excellent prognosis, some patients experience partial remission or progressive disease. We aimed to evaluate clinicopathologic differences in the treatment responder group by comparing complete remission (CR) and non-complete remission (non-CR). Materials and Methods: This study retrospectively reviewed 48 patients who were diagnosed with ocular adnexal MALT lymphoma at Ulsan University Hospital between March 2002 and August 2018. Patients who were followed up for less than 6 months were excluded. Histologic and clinical features were analyzed. The patients were divided into two groups: CR and non-CR. Results: Among the 48 patients, 33 achieved CR and 15 achieved non-CR during the median follow-up period of 40.00 months (range, 7-109 months). In univariable analysis, more patients tend to undergo treatment in the CR group, and post-radiotherapy (post-RT) SUVmax, PET and serum lactate dehydrogenase (LDH) levels were higher in the non-CR group (p = 0.043, p = 0.016, and p = 0.042, respectively). In a multivariable analysis, only application of treatment, including radiotherapy or chemotherapy with immunotherapy, was related to CR (odd ratio 7.301, 95% confidence interval 1.273-41.862, p = 0.026). In subgroup analysis according to the site of involvement, none of the variables were significant except for the post-RT SUVmax of PET and level of serum LDH in the non-conjunctiva group (p = 0.026, and p = 0.037, respectively). Seven (14.6%) patients had a recurrence, and those with a recurring site other than the primary site had a higher Ki-67 labeling index, although it was not statistically significant (9.56% vs. 18.00%, p = 0.095). Conclusions: Although belonging to the early stages, the non-CR rate was high in patients with high serum LDH levels, and recurred patients had higher Ki-67. Thus, considering active treatment is recommended in this group of patients.

The Biology of Ocular Adnexal Marginal Zone Lymphomas

This review focuses on the biology of ocular adnexal marginal zone B-cell lymphomas of the mucosa-associated lymphatic tissue (MALT) (OAMZL) subtype. The ocular adnexa includes all structures and tissues within the orbit except for the eye bulb. In the region of the ocular adnexa, MALT lymphomas represent the most common subtype of lymphoma, accounting for around 8% of all non-Hodgkin lymphomas. These lymphomas are often preceded by inflammatory precursor lesions. Either autoantigens or infectious antigens may lead to disease development by functioning as continuous antigenic triggers. This triggering leads to a constitutive activation of the NF-κB signaling pathway. The role of antigenic stimulation in the pathogenesis of OAMZL is supported by the detection of somatic mutations (partially with further intraclonal diversity) in their rearranged immunoglobulin V genes; hence, their derivation from germinal-center-experienced B cells, by a restricted IGHV gene usage, and the validation of autoreactivity of the antibodies in selected cases. In the established lymphomas, NF-κB activity is further enforced by mutations in various genes regulating NF-κB activity (e.g., TNFAIP3, MYD88), as well as recurrent chromosomal translocations affecting NF-κB pathway components in a subset of cases. Further pathogenetic mechanisms include mutations in genes of the NOTCH pathway, and of epigenetic regulators. While gene expression and sequencing studies are available, the role of differential methylation of lymphoma cells, the role of micro-RNAs, and the contribution of the microenvironment remain largely unexplored.

The Effect of the Tumor Microenvironment on Lymphoid Neoplasms Derived from B Cells

Lymphomas are characteristic tumors surrounded by an inflammatory microenvironment. The cells of the microenvironment are essential for the growth and survival of neoplastic cells and are recruited through the effect of cytokines/chemokines. Lymphomas include heterogeneous groups of neoplasms infiltrating various lymphoid structures which may arise from B lymphocytes, T lymphocytes, and natural killer (NK) cells at various stages of their differentiation state. In this review article, we analyze the literature data concerning the involvement of the tumor microenvironment (TME) in the progression of lymphomas and the recent advances in the analysis of microenvironment components in the most common forms: some mature B cell lymphoma neoplasms and classic Hodgkin lymphomas. The complex crosstalk between the TME and tumor cells led to the discovery of many mechanisms usable as molecular-targeted therapy through the control of diverse elements of the TME, varying from inhibitors of angiogenic cytokines and their receptors to the regulation of cells' activities and the novel immune checkpoint inhibitors.

Ocular adnexal lymphoma: an updated review of pathogenesis, diagnosis, and treatment

Lymphoma is the most common primary tumor of the orbit, accounting for 55% of all orbital malignancies. When divided into histopathological subtypes, extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) comprises the largest proportion. Clinical manifestations are unspecific, but in patients with slow-growing painless orbital mass, or red conjunctival lesion suggestive of ‘salmon patch’, ocular adnexa lymphoma (OAL) should be suspected. Although the pathogenetic mechanism of ocular adnexal MALT lymphoma (OAML) is not yet fully understood, the relationship between OAML and Chlamydia psittaci has been hypothesized recently, similar to that between gastric MALT lymphoma and Helicobacter pylori. This suggests a new treatment option for OAML; bacterial eradication therapy with systemic antibiotics. Several other treatment methods for OAML have been introduced, but no treatment guidelines have been established yet. In this article, we summarize the current knowledge on the clinical features, pathogenesis, diagnostic methods, therapeutic strategies, and prognosis of OAML.

Microbiota and cancer: current understanding and mechanistic implications

During last few decades, role of microbiota and its importance in several diseases has been a hot topic for research. The microbiota is considered as an accessory organ for maintaining normal physiology of an individual. These microbiota organisms which normally colonize several epithelial surfaces are known to secrete several small molecules leading to local and systemic effects on normal biological processes. The role of microbiota is also established in carcinogenesis as per several recent findings. The effects of microbiota on cancer is not only limited to their contribution in oncogenesis, but the overall susceptibility for oncogenesis and its subsequent progression, development of coinfections, and response to anticancer therapy is also found to be affected by microbiota. The information about microbiota and subsequent contributions of microbes in anticancer response motivated researchers in development of microbes-based anticancer therapeutics. We provided current status of microbiota contribution in oncogenesis with special reference to their mechanistic implications in different aspects of oncogenesis. In addition, the mechanistic implications of bacteria in anticancer therapy are also discussed. We conclude that several mechanisms of microbiota-mediated regulation of oncogenesis is known, but approaches must be focused on understanding contribution of microbiota as a community rather than single organisms-mediated effects.

A comprehensive review on avian chlamydiosis: a neglected zoonotic disease

Avian chlamydiosis is one of the important neglected diseases with critical zoonotic potential. Chlamydia psittaci, the causative agent, affects most categories of birds, livestock, companion animals, and humans. It has many obscured characters and epidemiological dimensions, which makes it unique among other bacterial agents. Recent reports on transmission from equine to humans alarmed the public health authorities, and it necessitates the importance of routine screening of this infectious disease. High prevalence of spill-over infection in equines was associated with reproductive losses. Newer avian chlamydial species are being reported in the recent years. It is a potential biological warfare agent and the disease is an occupational hazard mainly to custom officers handling exotic birds. Prevalence of the disease in wild birds, pet birds, and poultry causes economic losses to the poultry industry and the pet bird trade. Interestingly, there are speculations on the ‘legal’ and ‘illegal’ bird trade that may be the global source of some of the most virulent strains of this pathogen. The mortality rate generally ranges from 5 to 40% in untreated cases, but it can sometimes be higher in co-infection. The intracellular lifestyle of this pathogen makes the diagnosis more complicated and there is also lack of accurate diagnostics. Resistance to antibiotics is reported only in some pathogens of the Chlamydiaceae family, but routine screening may assess the actual situation in all pathogens. Due to the diverse nature of the pathogen, the organism necessitates the One Health partnerships to have complete understanding. The present review focuses on the zoonotic aspects of avian chlamydiosis with its new insights into the pathogenesis, transmission, treatment, prevention, and control strategies. The review also briefs on the basic understandings and complex epidemiology of avian chlamydiosis, highlighting the need for research on emerging one health perspectives.

Bacterial Infection and Non-Hodgkin B-Cell Lymphoma: Interactions between Pathogen, Host and the Tumor Environment

Non-Hodgkin B-cell lymphomas (NHL) are a heterogeneous group of lymphoid neoplasms with complex etiopathology, rich symptomatology, and a variety of clinical courses, therefore requiring different therapeutic approaches. The hypothesis that an infectious agent may initiate chronic inflammation and facilitate B lymphocyte transformation and lymphogenesis has been raised in recent years. Viruses, like EBV, HTLV-1, HIV, HCV and parasites, like Plasmodium falciparum, have been linked to the development of lymphomas. The association of chronic Helicobacter pylori (H. pylori) infection with mucosa-associated lymphoid tissue (MALT) lymphoma, Borrelia burgdorferi with cutaneous MALT lymphoma and Chlamydophila psittaci with ocular adnexal MALT lymphoma is well documented. Recent studies have indicated that other infectious agents may also be relevant in B-cell lymphogenesis such as Coxiella burnettii, Campylobacter jejuni, Achromobacter xylosoxidans, and Escherichia coli. The aim of the present review is to provide a summary of the current literature on infectious bacterial agents associated with B-cell NHL and to discuss its role in lymphogenesis, taking into account the interaction between infectious agents, host factors, and the tumor environment.

Emerging Roles for the Gut Microbiome in Lymphoid Neoplasms

Lymphoid neoplasms encompass a heterogeneous group of malignancies with a predilection for immunocompromised individuals, and the disease burden of lymphoid neoplasms has been rising globally over the last decade. At the same time, mounting studies delineated a crucial role of the gut microbiome in the aetiopathogenesis of various diseases. Orchestrated interactions between myriad microorganisms and the gastrointestinal mucosa establish a defensive barrier for a range of physiological processes, especially immunity and metabolism. These findings provide new perspectives to harness our knowledge of the gut microbiota for preclinical and clinical studies of lymphoma. Here, we review recent findings that support a role for the gut microbiota in the development of lymphoid neoplasms and pinpoint relevant molecular mechanisms. Accordingly, we propose the microbiota-gut-lymphoma axis as a promising target for clinical translation, including auxiliary diagnosis, novel prevention and treatment strategies, and predicting clinical outcomes and treatment-related adverse effects of the disease in the future. This review will reveal a fascinating avenue of research in the microbiota-mediated lymphoma field.

The Hypothetical Inclusion Membrane Protein CPSIT_0846 Regulates Mitochondrial-Mediated Host Cell Apoptosis via the ERK/JNK Signaling Pathway

Chlamydia psittaci is an important zoonotic factor associated with human and animal atypical pneumonia. Resisting host cell apoptosis is central to sustaining Chlamydia infection in vivo. Chlamydia can secrete inclusion membrane proteins (Incs) that play important roles in their development cycle and pathogenesis. CPSIT_0846 is an Inc protein in C. psittaci identified by our team in previous work. In the current study, we investigated the regulatory role of CPSIT_0846 in HeLa cell apoptosis, and explored potential mechanisms. The results showed that HeLa cells treated with CPSIT_0846 contained fewer apoptotic bodies and exhibited a lower apoptotic rate than untreated cells either with Hoechst 33258 fluorescence staining or flow cytometry with or without induction by staurosporine (STS). CPSIT_0846 could increase the phosphorylation of the extracellular signal-regulated kinases 1/2 (ERK1/2) or stress-activated protein kinases/c-Jun amino-terminal kinases (SAPK/JNK) signaling pathways, and the Bcl-2 associated X protein (Bax)/B cell lymphoma 2 (Bcl-2) ratio, levels of cleaved caspase-3/9 and cleaved Poly-ADP-ribose polymerase (PARP) were significantly up-regulated following inhibition of ERK1/2 or SAPK/JNK pathways with U0126 or SP600125. After carbonyl cyanide 3-chlorophenylhydrazone (CCCP) treatment, the mitochondrial membrane potential (MMP) of cells was significantly decreased in control group, but stable in the CPSIT_0846 treated one, and less cytochrome c (Cyt.c) was released into the cytoplasm. Inhibition of the ERK1/2 or SAPK/JNK pathway significantly decreased the JC-1 red-green fluorescence signal, and promoted Cyt.c discharge into the cytoplasm in HeLa cells treated with CPSIT_0846. In conclusion, CPSIT_0846 can regulate mitochondrial pathway-mediated apoptosis in HeLa cells by activating the ERK/JNK signaling pathway.

Orbital and Eyelid B-Cell Lymphoma: A Multicenter Retrospective Study

Simple Summary

The treatment of orbital and eyelid B-cell lymphoma remains a field of progress. The aim of our study was to analyze patients diagnosed, staged and treated for orbital and eyelid B-cell lymphoma to assess clinical characteristics, treatment outcomes and recurrence patterns. We included in this study 141 cases of orbital and eyelid B-cell lymphoma. We found five lymphoma subtypes and we confirmed that the histopathologic subtype and the type of treatment were found to be the main factors influencing treatment outcome.

Abstract

Background: The aim of this study was to analyze patients diagnosed, staged and treated for orbital and eyelid B-cell lymphoma (OEL). Methods: One hundred and forty-one cases of OEL were included in this study. Primary endpoints were to analyze the histopathologic findings, the main risk factors and the type of treatment and to correlate them with recurrence of OEL. The secondary endpoint was to determine the progression-free survival (PFS) time. Results: Extranodal marginal zone B-cell lymphoma was the most frequent subtype (66%), followed by small lymphocytic lymphoma (12.7%), diffuse large B-cell lymphoma (DLBCL) (9.2%), follicular lymphoma (6.6%), mantle cell lymphoma (4.3%) and Burkitt lymphoma (1.2%). The probability of relapse was influenced by the histopathologic subtype DLBCL (OR = 7.7, 95% CI 1.8–32.3) and treatment with chemotherapy (OR = 14.9, 95% CI 2.6–83.7). Multivariate analysis showed that the histopathologic subtype DLBCL and chemotherapy treatment retained statistical significance for a poorer PFS, with hazard ratios of 8.581 (p = 0.0112) and 9.239 (p = 0.0094), respectively. Conclusions: Five lymphoma subtypes were found in patients with OEL. The histopathologic subtype and the type of treatment were found to be the main factors influencing treatment outcome.

TBL1XR1 Mutations in Primary Marginal Zone Lymphomas of Ocular Adnexa are Associated with Unique Morphometric Phenotypes

PURPOSE

Extranodal marginal zone B-cell lymphoma (EMZL) of mucosa-associated lymphoid tissue (MALT) that affects the ocular adnexa, also known as ocular adnexal MALT lymphomas (OAML), are low-grade lymphomas that mostly affect elderly individuals. This study was conducted to explore the genetic and microbial drivers of OMAL, and unique morphometric phenotypes associated with these mutations and infections.

MATERIALS AND METHODS

In this study, we performed targeted deep sequencing of 8 OAML cases to identify its potential genetic and microbial drivers. We additionally performed computational digital image analysis of cases to determine if morphologic features corresponded to genetic mutations and disease biology.

RESULTS

We identified TBL1XR1 as recurrently mutated in OAML (4/8), and mutations in several other oncogenes, tumor suppressors, transcription regulators, and chromatin remodeling genes. Morphologically, OAML cases with mutations in TBL1XR1 showed lymphoma cells with significantly lower circularity and solidity by computational digital image analysis (p-value <0.0001). Additionally, cases of OAML with mutations in TBL1XR1 showed equivalent or increased vascular density compared to cases without mutations in TBL1XR1. Finally, we did not find any infectious microbial organisms associated with OAML.

CONCLUSIONS

Our study showed recurrent mutations in TBL1XR1 are associated with unique morphometric phenotypes in OMAL cases. Additionally, mutations in genes associated with the methylation status of histone 3, nuclear factor (NF)-κB pathway, and NOTCH pathway were enriched in OMAL cases. Our findings have biologic and clinical implications as mutations in TBL1XR1 and other genes have the potential to be used as markers for the diagnosis of OAML, and also demonstrate a specific biologic phenotypic manifestation of TBL1XR1 mutations.

Radiotherapy alone for stage IE ocular adnexal mucosa-associated lymphoid tissue lymphomas: long-term results

Background

To evaluate the long-term efficacy and toxicity of radiation therapy in patients with Stage IE primary ocular adnexal mucosa-associated lymphoid tissue lymphoma.

Methods

We designed a retrospective analysis to evaluate 81 patients with ocular adnexal mucosa-associated lymphoid tissue lymphoma treated with radiation therapy between 2006 and 2016. The median radiation dose was 30 Gy (range, 30–36 Gy in 15–18 fractions). Local control, progression-free survival, overall survival, and cumulative incidence of Grade 3 cataract were calculated by using the Kaplan–Meier method.

Result

The median follow-up time was 74 months (range, 4–157 months). The 5-year local control was 100%. Although local relapse was suspected in 3 patients after radiation therapy, 2 patients were pathologically diagnosed as IgG4-related inflammation and in 1 patient as intense inflammatory cell infiltration. The 5-year progression-free survival was 94.4%. Five patients had relapse at distant sites. The 5-year overall survival was 98.8%. Twenty patients had Grade 3 cataract. The 5-year cumulative incidences of Grade ≥ 3 and Grade ≥ 2 cataract for 58 patients treated without a lens shield were 38 and 40%, respectively. The incidence of Grade ≥ 3 cataract was 42% for 50 patients treated with 6-MV X-rays (estimated lens dose: 29 Gy) and 17% for 8 patients treated with 9-MeV electrons (estimated lens dose: 24 Gy).

Conclusions

Radiation therapy alone yielded excellent local control and long-term survival in Stage IE ocular adnexal mucosa-associated lymphoid tissue lymphoma. Long-term observation with careful attention to relapse at distant sites is necessary. In the case of suspected local relapse, IgG4-related disease should be carefully ruled out.

Spectroscopic analysis of chlamydial major outer membrane protein in support of structure elucidation

Chlamydial major outer membrane protein (MOMP) is the major protein constituent of the bacterial pathogen Chlamydia trachomatis. Chlamydia trachomatis Serovars D–K are the leading cause of genital tract infections which can lead to infertility or ectopic pregnancies. A vaccine against Chlamydia is highly desirable but currently not available. MOMP accounts for ~ 60% of the chlamydial protein mass and is considered to be one of the lead vaccine candidates against C. trachomatis. We report on the spectroscopic analysis of C. trachomatis native MOMP Serovars D, E, F, and J as well as C. muridarum MOMP by size exclusion chromatography multi angle light scattering (SEC MALS), circular dichroism (CD) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR‐FTIR). MOMP was purified from the native bacterium grown in either adherent HeLa cells or in different suspension cell lines. Our results confirm that MOMP forms homo‐trimers in detergent micelles. The secondary structure composition of C. trachomatis MOMP was conserved across serovars, but different from composition of C. muridarum MOMP with a 13% (CD) to 18% (ATR‐FTIR) reduction in β‐sheet conformation for C. trachomatis MOMP. When Serovar E MOMP was isolated from suspension cell lines the α‐helix content increased by 7% (CD) to 13% (ATIR‐FTIR). Maintenance of a native‐like tertiary and quaternary structure in subunit vaccines is important for the generation of protective antibodies. This biophysical characterization of MOMP presented here serves, in the absence of functional assays, as a method for monitoring the structural integrity of MOMP.

Conjunctival dysbiosis in mucosa-associated lymphoid tissue lymphoma

To investigate the conjunctival microbiota and the association between the development of conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma and dysbiosis, DNA samples were collected from 25 conjunctival MALT lymphoma patients and 25 healthy controls. To compare the microbiota, samples were collected from the following four body locations: conjunctiva, meibomian gland, periocular skin and hand. Extracted DNA was analyzed by 16S rRNA sequences, and libraries were sequenced on an Illumina MiSeq sequencer. The differences in bacteria were characterized by using principal coordinate analysis of metagenomics data, and the differences in bacterial compositions were evaluated by linear discriminant analysis effect size. The conjunctival microbiota of MALT lymphoma patients was compositionally different from that of healthy controls. For the conjunctival MALT lymphoma patients, alterations in the microbial composition were detected, and a remarkable change was detected at the conjunctiva. Detailed analysis showed that a specific population of the microbiota, the genus Delftia, was significantly more abundant in conjunctival MALT lymphoma patients, and the genera Bacteroides and Clostridium were less abundant in the MALT lymphoma patients. A specific microbiota on the ocular surface in conjunctival MALT lymphoma patients was detected, and dysbiosis may play an important role in the pathophysiology of conjunctival MALT lymphoma.

Update on conjunctival pathology

Conjunctival biopsies constitute a fairly large number of cases in a typical busy ophthalmic pathology practice. They range from a single biopsy through multiple mapping biopsies to assess the extent of a particular pathological process. Like most anatomical sites, the conjunctiva is subject to a very wide range of pathological processes. This article will cover key, commonly encountered nonneoplastic and neoplastic entities. Where relevant, sections will include recommendations on how best to submit specimens to the ophthalmic pathology laboratory and the relevance of up-to-date molecular techniques.

Molecular prevalence and genotyping of Chlamydia spp. in wild birds from South Korea

Wild birds are reservoirs for Chlamydia spp. Of the total 225 samples from wild birds during January to September 2016 in Korea, 4 (1.8%) and 2 (0.9%) showed positive for Chlamydia psittaci and Chlamydia gallinacea, respectively. Phylogenetic analyses and comparisons of sequence identities for outer-membrane protein A (ompA) revealed that Korean C. psittaci fall into three previously known genotypes; genotype E, 1V and 6N, whereas the Korean C. gallinacea were classified as new variants of C. gallinacea. Our study demonstrates that wild birds in South Korea carry at least two Chlamydia species: C. psittaci and C. gallinacea, and provides new information on the epidemiology of avian chlamydiosis in wild birds.

Establishment of a combination scoring method for diagnosis of ocular adnexal lymphoproliferative disease

Lymphoproliferative diseases (LPDs) of the ocular adnexa encompass the majority of orbital diseases and include reactive follicular hyperplasia (RFH), atypical lymphoid hyperplasia (ALH), and mucosa-associated lymphoid tissue lymphoma (MALToma). Lymphoid follicles (LFs) are usually observed during the histological examination of LPDs. Currently, because there is a lack of specific clinical signs and diagnostic immunohistochemical biomarkers, it is difficult for pathologists to distinguish MALToma from ocular RFH and ALH, which makes the clinical management of these conditions difficult. Here, we analyzed the clinical features of patients with ocular adnexal LPDs (n = 125) and investigated the structure of LFs in paraffin-embedded tissue samples using anti-CD23 and anti-IgD immunochemistry. We found that some clinical features including age, sex, and laterality were different among RFH, LFH, and MALToma. Additionally, immunohistochemistry revealed that the expression of IgD and CD23 was higher in RFH patients and decreased in patients with ALH and MALToma. Moreover, LFs in RFH were intact, whereas the structures of most LFs were disrupted in ALH. In MALToma specimens, few intact LFs were observed. In a further investigation, we combined the results for CD23/IgD immunohistochemistry and the structure of LFs to establish a scoring method for the differential diagnosis of LPDs. According to the BIOMED-2 protocol, we further detected IgH gene monoclonal rearrangement in 73 cases (35 RFH, 17 ALH, and 21 MALToma cases). The sensitivity of our scoring method, based on a comparison with the results of IgH gene monoclonal rearrangement detection, was 85.7% (18/21) for MALToma and 35.3% (6/17) for ALH. Our study provides a method that may be useful for the differential diagnosis of RFH, ALH, and MALToma.

Lymphoproliferative Tumors of the Ocular Adnexa

The ocular adnexa include the eyelids, conjunctiva, lacrimal apparatus, and orbital soft tissue. One percent of all lymphomas and approximately 8% of all extranodal lymphomas arise in the ocular adnexa and their incidence is increasing. Reactive lymphoid hyperplasia comprises 16% of all lymphoproliferative tumors of the ocular adnexa. The relative frequencies of ocular adnexal lymphoma presentation are in the orbit, 37%; conjunctiva, 29%; lacrimal apparatus, 20%; and eyelid, 14%. The most frequent primary lymphoma types of the ocular adnexa are extranodal marginal zone lymphoma, 62%; follicular lymphoma, 17%; and diffuse large B-cell lymphoma, 10%. The eyelids show the highest proportion of secondary lymphoma involvement, 49% of all eyelid lymphoproliferative lesions, compared with 24% in all ocular adnexa. The specific aspects of the site, histologic, immunohistochemical, cytogenetic, and molecular findings of the most relevant lymphoma types occurring in the various parts of the ocular adnexa will be discussed in relation to clinical parameters and relevance for therapy choice. Furthermore, the implications of the updated version of the World Health Organization Classification of Tumours of Haematopoietic and Lymphoid Tissues in relation to ocular adnexal lymphoma are reviewed.

Comprehensive polymerase chain reaction assay for detection of pathogenic DNA in lymphoproliferative disorders of the ocular adnexa

Infectious agents have been identified as a major cause of specific types of human cancers worldwide. Several microorganisms have been identified as potential aggravators of ocular adnexal neoplasms; however, given the rarity of these neoplasms, large epidemiological studies are difficult to coordinate. This study aimed to conduct an exhaustive search for pathogenic DNA in lymphoproliferative disorders (LPD) of the ocular adnexa in a total of 70 patients who were diagnosed with LPD of the ocular adnexa between 2008 and 2013. Specimens were screened for bacterial, viral, fungal, and parasitic DNA by multiplex polymerase chain reaction (PCR) and quantitative real-time PCR. Among cases of conjunctival mucosa-associated lymphoid tissue lymphoma, human herpes virus (HHV)-6, HHV-7, chlamydia, Epstein-Barr virus (EBV) and bacterial 16S ribosomal DNA were detected. In cases of IgG4-related ocular disease, similar pathogens were detected but in a larger number of patients. Our PCR assays detected DNAs of various infectious agents in tumor specimens, especially HHV6, HHV7, and EBV, with different positive rates in various types of LPD. Chronic inflammatory stimulation or activation of oncogenes from these infectious agents might be involved in the pathogenesis of LPD of the ocular adnexa.

[Lymphoma of the ocular adnexa]

BACKGROUND

Lymphomas of the ocular adnexa are heterogeneous and demonstrate a wide range of clinical, histological, immunohistochemical and molecular genetic characteristics.

AIM

The aim of this article is to give an overview of the interdisciplinary diagnostics and individually adapted lymphoma subtype-based therapy.

DIAGNOSTICS

Depending on the lymphoma localisation, i.e. whether in the eyelid, the conjunctiva or in the orbit, a photograph or a radiological scan is required to record the tumor extent. Visual function is more likely to be impacted when the lymphoma arises in the posterior orbit, close to the optic nerve and imaging diagnostics are therefore necessary. Histological investigations are essential for confirming the lymphoma diagnosis and give information about the particular subtype, which in turn will determine subsequent patient management, Clinical staging investigations for determining the systemic extent of the lymphoma manifestation (e.g. imaging, blood analyses as well as bone marrow biopsy) are mandatory.

THERAPY

External beam radiation, local and systemic chemotherapy or in some cases antibiotics are treatment options after surgical excision in isolated ocular adnexal lymphoma. The TNM classification of the American Joint Committee on Cancer or the Ann Arbor staging system, as well as the guidelines of the German Society of Hematology and Medical Oncology are all tools to aid the choice of the appropriate individually adapted therapy for systemic disease, which includes psycho-oncological care.

Infectious Aetiology of Marginal Zone Lymphoma and Role of Anti-Infective Therapy

Marginal zone lymphomas have been associated with several infectious agents covering both viral and bacterial pathogens and in some cases a clear aetiological role has been established. Pathogenetic mechanisms are currently not completely understood. However, the role of chronic stimulation of the host immune response with persistent lymphocyte activation represents the most convincing explanation for lymphoproliferation. Gastric MALT lymphoma is strictly associated with Helicobacter pylori infection and various eradicating protocols, developed due to increasing antibiotic resistance, represent the first line therapy for gastric MALT. The response rate to eradication is good with 80% of response at 1 year; this finding is also noteworthy because it recapitulates cancer cured only by the antibacterial approach and it satisfies the Koch postulates of causation, establishing a causative relationship between Hp and gastric MALT lymphoma. Patients with chronic HCV infection have 5 times higher risk to develop MZL, in particular, an association with splenic and nodal MZL has been shown in several studies. Moreover, there is evidence of lymphoma regression after antiviral therapy with interferon+ribavirin, thus raising hope that newly available drugs, extremely efficient against HCV replication, could improve outcome also in HCV-driven lymphomas. Another case-study are represented by those rare cases of MZL localized to orbital fat and eye conjunctivas that have been associated with Chlamydophila psittaci infection carried by birds. Efficacy of antibacterial therapy against C. psittaci are conflicting and generally poorer than gastric MALT. Finally, some case reports will cover the relationship between primary cutaneous B-cell Lymphomas and Borrelia Burgdorferi.

Molecular pathogenesis of lymphomas of mucosa-associated lymphoid tissue--from (auto)antigen driven selection to the activation of NF-κB signaling

Lymphomas of mucosa-associated lymphoid tissue (MALT) are typically present at sites such as the stomach, lung or urinary tract, where lymphoid tissues scatter in mucosa lamina propria, intra- or sub-epithelial cells. The infection of certain pathogens, such as Helicobacter pylori, Chlamydophila psittaci, Borrelia burgdorferi, hepatitis C virus, or certain autoantigens cause these sites to generate a germinal center called the "acquired lymphoid tissue". The molecular pathogenesis of MALT lymphoma is a multi-step process. Receptor signaling, such as the contact stimulation of B cell receptors and CD4 positive T cells mediated by CD40/CD40-ligand and T helper cell type 2 cytokines like interleukin-4, contributes to tumor cell proliferation. A number of genetic alterations have been identified in MALT lymphoma, and among them are important translocations, such as t(11;18)(q21;q21), t(1;14)(p22;q32), t(14;18)(q32;q21) and t(3;14)(p13;q32). Fusion proteins generated by these translocations share the same NF-κB signaling pathway, which is activated by the caspase activation and recruitment domain containing molecules of the membrane associated guanylate kinase family, B cell lymphoma-10 and MALT1 (CBM) protein complex. They act downstream of cell surface receptors, such as B cell receptors, T cell receptors, B cell activating factors and Toll-like receptors, and participate in the biological process of MALT lymphoma. The discovery of therapeutic drugs that exclusively inhibit the antigen receptor signaling pathway will be beneficial for the treatment of B cell lymphomas in the future.

A subset of ocular adnexal marginal zone lymphomas may arise in association with IgG4-related disease

We previously suggested a relationship between ocular immunoglobulin (Ig)G4-related disease (IgG4-RD) and marginal zone lymphomas (MZLs). However, the cytokine background associated with these disorders and whether it differs between ocular adnexal MZLs with (IgG4-associated MZL) and without (IgG4-negative MZL) numerous IgG4⁺ plasma cells are unknown. In this study, we identified the mRNA expression pattern of Th2 and regulatory T-cell (Treg) cytokines in IgG4-RD and in IgG4-associated MZL and IgG4-negative MZL using real-time polymerase chain reaction analysis. Ocular IgG4-RD and IgG4-associated MZL exhibited significantly higher expression ratios of interleukin (IL)-4/β-actin, IL-10/β-actin, IL-13/β-actin, transforming growth factor (TGF) β1/β-actin, and FOXP3/β-actin than did IgG4-negative MZL (p < 0.05). This finding further supports our prior observations that a significant subset of ocular MZLs arises in the setting of IgG4-RD. Furthermore, the presence of a different inflammatory background in IgG4-negative MZLs suggests that IgG4-associated MZLs may have a different pathogenesis.

Clinicopathological Analysis of Ocular Adnexal Extranodal Marginal Zone B-Cell Lymphoma with IgG4-Positive Cells

This study aims to analyze clinical and pathological characteristics of ocular adnexal extranodal marginal zone B-cell lymphoma (EMZL) accompanying IgG4-positive cells. Fifty patients with a diagnosis of primary non-conjunctival ocular adnexal EMZL were enrolled in this study. The number of IgG4-positive cells and the ratio of IgG/IgG4 were evaluated by immunohistochemistry in the biopsy specimens. The patients were divided into two groups based on the absolute number and the ratio of IgG4-positive cells (IgG4-posivite vs IgG4-negative groups). The demographic data, clinical staging at diagnosis, histopathological characteristics, and response to initial treatment were comparatively analyzed between the 2 groups. Five (10%) of 50 patients were defined as IgG4-positive group, and all the cases showed characteristic histological features such as extensive plasma cell infiltration and dense fibrosis. Most of these patients (4 of 5 patients) had lymphoma of the lacrimal gland. The patients from the IgG4-positive group showed a lower response rate to initial treatment (87.5 vs 33%, p = 0.03) than IgG4-negative group with a median follow-up period of 38 months. A part of the ocular adnexal EMZLs were accompanied with IgG4-positive cells. Significantly, most IgG4-positive ocular adnexal EMZLs occurred in the lacrimal gland, and can be related with a more frequent treatment failure.

Mechanisms and clinical applications of chromosomal instability in lymphoid malignancy

Lymphocytes are unique among cells in that they undergo programmed DNA breaks and translocations, but that special property predisposes them to chromosomal instability (CIN), a cardinal feature of neoplastic lymphoid cells that manifests as whole chromosome- or translocation-based aneuploidy. In several lymphoid malignancies translocations may be the defining or diagnostic markers of the diseases. CIN is a cornerstone of the mutational architecture supporting lymphoid neoplasia, though it is perhaps one of the least understood components of malignant transformation in terms of its molecular mechanisms. CIN is associated with prognosis and response to treatment, making it a key area for impacting treatment outcomes and predicting prognoses. Here we will review the types and mechanisms of CIN found in Hodgkin lymphoma, non-Hodgkin lymphoma, multiple myeloma and the lymphoid leukaemias, with emphasis placed on pathogenic mutations affecting DNA recombination, replication and repair; telomere function; and mitotic regulation of spindle attachment, centrosome function, and chromosomal segregation. We will discuss the means by which chromosome-level genetic aberrations may give rise to multiple pathogenic mutations required for carcinogenesis and conclude with a discussion of the clinical applications of CIN and aneuploidy to diagnosis, prognosis and therapy.

Immunohistochemical analysis indicates that the anatomical location of B-cell non-Hodgkin's lymphoma is determined by differentially expressed chemokine receptors, sphingosine-1-phosphate receptors and integrins

Background

The aim of this study was to elucidate the mechanisms responsible for the location of B-cell non-Hodgkin’s lymphoma (B-NHL) at different anatomical sites. We speculated that the malignant B cells in these disorders have the potential for trafficking between blood and secondary lymphoid organs (SLO) or extranodal sites and that their preferential accumulation at different locations is governed by the expression of key molecules that regulate the trafficking of normal lymphocytes.

Methods

Biopsy or blood samples from 91 cases of B-NHL affecting SLO (n = 27), ocular adnexae (n = 51) or blood (n = 13) were analysed by immunohistochemistry or flow cytometry for the expression of the following molecules: CCR7, CCL21 and αL (required for the entry of normal lymphocytes into SLO); CXCR4, CXCL12 and α4 (required for entry into extranodal sites); CXCR5, CXCL13 and S1PR2 (required for tissue retention); S1PR1 and S1PR3 (required for egress into the blood). The expression of each of these molecules was then related to anatomical location and histological subtype.

Results

The expression of motility/adhesion molecules varied widely between individual patient samples and correlated much more strongly with anatomical location than with histological subtype. SLO lymphomas [comprising 10 follicular lymphoma (FL), 8 diffuse large B-cell lymphoma (DLBCL), 4 mantle-cell lymphoma (MCL) and 5 marginal-zone lymphoma (MZL)] were characterised by pronounced over-expression of S1PR2, suggesting that the malignant cells in these lymphomas are actively retained at the site of clonal expansion. In contrast, the malignant B cells in ocular adnexal lymphomas (10 FL, 9 DLBCL, 4 MCL and 28 MZL) expressed a profile of molecules suggesting a dynamic process of trafficking involving not only tissue retention but also egress via S1PR3 and homing back to extranodal sites via CXCR4/CXCL12 and α4. Finally, leukaemic lymphomas (6 FL, 5 MCL and 2 MZL) were characterised by aberrant expression of the egress receptor S1PR1 and low expression of molecules required for tissue entry/retention.

Conclusions

In summary, our study strongly suggests that anatomical location in B-NHL is governed by the differential expression of specific adhesion/motility molecules. This novel observation has important implications for therapeutic strategies that aim to disrupt protective micro-environmental interactions.

Electronic supplementary material

The online version of this article (doi:10.1186/s40164-015-0004-3) contains supplementary material, which is available to authorized users.

The first case of human autochtonous subconjunctival dirofilariosis in Poland and MALT lymphoma as possible consequence of this parasitosis

The first case of human dirofilarosis in Poland was recorded in 2007. Until that time our country was free of Dirofilaria repens. Recent studies show that 21,4- 60% of dogs in Warsaw region harbour microfilariae, therefore it is becoming a growing problem in Central Europe.

In April 2013 a subconjunctival D. repens was removed from the eye of 61-year-old woman. It was the twenty first case of this disease in Poland, the third case of eye dirofilaria and the fourth autochtonous case. The patient had never been abroad, so it was the first case of autochtonous human ocular dirofilariosis in Poland. Nine months after the D. repens had been removed, a MALT lymphoma was discovered. In the article we discuss whether a MALT lymphoma of the lacrimal gland of the eye, previously affected by the parasite, may be the consequence of the invasion.

Chlamydia psittaci: update on an underestimated zoonotic agent

Chlamydia (C.) psittaci is an economically relevant pathogen in poultry and pet birds, where it causes psittacosis/ornithosis, and also a human pathogen causing atypical pneumonia after zoonotic transmission. Despite its well-documented prevalence, the agent has received less attention by researchers than other Chlamydia spp. in the last decades. In the present paper, we review recently published data on C. psittaci infection and attempt to single out characteristic features distinguishing it from related chlamydial agents. It is remarkable that C. psittaci is particularly efficient in disseminating in the host organism causing systemic disease, which occasionally can take a fulminant course. At the cellular level, the pathogen's broad host cell spectrum (from epithelial cells to macrophages), its rapid entry and fast replication, proficient use of intracellular transport routes to mitochondria and the Golgi apparatus, the pronounced physical association of chlamydial inclusions with energy-providing cell compartments, as well as the subversive regulation of host cell survival during productive and persistent states facilitate the characteristic efficient growth and successful host-to-host spread of C. psittaci. At the molecular level, the pathogen was shown to upregulate essential chlamydial genes when facing the host immune response. We hypothesize that this capacity, in concert with expression of specific effectors of the type III secretion system and efficient suppression of selected host defense signals, contributes to successful establishment of the infection in the host. Concerning the immunology of host-pathogen interactions, C. psittaci has been shown to distinguish itself by coping more efficiently than other chlamydiae with pro-inflammatory mediators during early host response, which can, to some extent, explain the effective evasion and adaptation strategies of this bacterium. We conclude that thorough analysis of the large number of whole-genome sequences already available will be essential to identify genetic markers of the species-specific features and trigger more in-depth studies in cellular and animal models to address such vital topics as treatment and vaccination.

Genome-wide DNA methylation profiles according to Chlamydophila psittaci infection and the response to doxycycline treatment in ocular adnexal lymphoma

PURPOSE

To compare genome-wide DNA methylation profiles according to Chlamydophila psittaci (Cp) infection status and the response to doxycycline treatment in Korean patients with ocular adnexal extranodal marginal zone B-cell lymphoma (EMZL).

METHODS

Twelve ocular adnexal EMZL cases were classified into two groups (six Cp-positive cases and six Cp-negative cases). Among the 12 cases, eight were treated with doxycycline as first-line therapy, and they were divided into two groups according to their response to the treatment (four doxy-responders and four doxy-nonresponders). The differences in the DNA methylation states of 27,578 methylation sites in 14,000 genes were evaluated using Illumina bead assay technology. We also validated the top-ranking differentially methylated genes (DMGs) with bisulfite direct sequencing or pyrosequencing.

RESULTS

The Infinium methylation chip assay revealed 180 DMGs in the Cp-positive group (74 hypermethylated genes and 106 hypomethylated genes) compared to the Cp-negative group. Among the 180 DMGs, DUSP22, which had two significantly hypomethylated loci, was validated, and the correlation was significant for one CpG site (Spearman coefficient=0.6478, p=0.0262). Regarding the response to doxycycline treatment, a total of 778 DMGs were revealed (389 hypermethylated genes and 336 hypomethylated genes in the doxy-responder group). In a subsequent replication study for representative hypomethylated (IRAK1) and hypermethylated (CXCL6) genes, the correlation between the bead chip analysis and pyrosequencing was significant (Spearman coefficient=0.8961 and 0.7619, respectively, p<0.05).

CONCLUSIONS

Ocular adnexal EMZL showed distinct methylation patterns according to Cp infection and the response to doxycycline treatment in this genome-wide methylation study. Among the candidate genes, DUSP22 has a methylation status that was likely attributable to Cp infection. Our data also suggest that the methylation statuses of IRAK1 and CXCL6 may reflect the response to doxycycline treatment.

Diffuse large B-cell lymphoma and mantle cell lymphoma of the ocular adnexal region, and lymphoma of the lacrimal gland: an investigation of clinical and histopathological features

Diffuse large B-cell lymphoma (DLBCL) and mantle cell lymphoma (MCL) constitute two distinct subtypes of non-Hodgkin lymphoma (NHL) associated with considerable morbidity and mortality. Marked diversities with regard to molecular biology and clinical features are recognized in different subsets of the two lymphomas. Because these differences could be related to the location of the lymphoma, it is of interest to investigate the clinical and histopathological features of DLBCL and MCL involving the ocular adnexal region (i.e. the orbit, eyelids, conjunctiva, lacrimal gland and lacrimal sac). Similarly, the lacrimal gland is the only glandular structure within the orbit. Because the lacrimal gland represents an important part of the immunological system, it is of interest to investigate lymphomas involving this location with regard to clinical and histological characteristics.

PURPOSE

  To characterize the clinical and histopathological features of Danish patients with DLBCL of the ocular adnexal region between 1980 and 2009 and of Danish ocular adnexal MCL patients from 1980 to 2005. Furthermore, the aim of this PhD was to review all specimens from patients with lymphoma of the lacrimal gland in Denmark between 1975 and 2009 to determine the distribution of lymphoma subtypes of the lacrimal gland and to describe the clinicopathological features of these patients.

RESULTS

  A total of 34 patients with DLBCL and 21 with MCL of the ocular adnexal region were identified. Twenty-seven patients had lacrimal gland lymphoma, including four DLBCLs and three MCLs from studies I and II. Elderly patients predominated in all three groups, with median ages of 78, 75 and 69 years in the DLBCL, the MCL and the lacrimal gland lymphoma groups, respectively. MCL patients had a preponderance of males, whereas females prevailed among lacrimal gland lymphoma patients. The orbit was the most common site of involvement in DLBCL and MCL. Most DLBCL patients had unilateral involvement, while MCL patients had a high frequency of bilateral involvement. Similarly, localized lymphoma was relatively frequently seen in DLBCL patients in contrast to the predominance of disseminated lymphoma in the MCL group. The majority of lacrimal gland lymphomas were low grade, and the distribution of subtypes was as follows: extranodal marginal zone lymphoma, 10 (37%); follicular lymphoma, 5 (19%); DLBCL, 4 (15%); MCL, 3 (11%); chronic lymphocytic leukaemia/small lymphatic lymphoma, 2 (7%); and unclassified B-cell lymphoma, 3 (11%). The overall survival rates at 3 and 5 years for the entire study group of DLBCL were 42% and 20%, whereas 58% and 22% of MCL patients were alive 3 and 5 years after the time of diagnosis. The 5-year overall survival rate of lacrimal gland lymphoma patients was 70%. Concordant bone marrow involvement and the International Prognostic Index score were predictive factors for the overall survival in the DLBCL group in Cox regression analysis. Rituximab-containing chemotherapy was associated with an improved survival rate in MCL patients.

CONCLUSIONS

  Diffuse large B-cell lymphoma and MCL involving the ocular adnexal region and lymphoma of the lacrimal gland are prevalent among elderly patients. The overall prognosis in DLBCL and MCL was poor, whereas the prognosis for lacrimal gland lymphoma patients was relatively good. Concordant bone marrow involvement and the International Prognostic Index score were independent predictive factors for mortality in the DLBCL group. Chemotherapy containing rituximab significantly improved survival in the MCL group.

The Elusive but Pathogenic Peptidoglycan of Chlamydiae

Chlamydia species cause a broad spectrum of diseases in humans including severe chronic sequelae related to persistent forms. Despite the lack of detectable amounts of peptidoglycan, several studies suggest the presence of small quantities of peptidoglycan or its derivative at least in some stages of the growth cycle. Based on recent discovery in Chlamydiae of the aminotransferase pathway for biosynthesis of meso-diaminopimelic acid, we demonstrated the up-regulation of the gene (cp0259) encoding L,L-diaminopimelate aminotransferase in chlamydial persistent forms. This finding may be important in the search for target molecules to diagnose and treat Chlamydia-associated chronic diseases.

Signaling pathways bridging microbial-triggered inflammation and cancer

Microbial-triggered inflammation protects against pathogens and yet can paradoxically cause considerable secondary damage to host tissues that can result in tissue fibrosis and carcinogenesis, if persistent. In addition to classical pathogens, gut microbiota bacteria, i.e. a group of mutualistic microorganisms permanently inhabiting the gastrointestinal tract and which plays a key role in digestion, immunity, and cancer prevention, can induce inflammation-associated cancer following the alterations of their microenvironment. Emerging experimental evidence indicates that microbiota members like Escherichia coli and several other genotoxic and mutagenic pathogens can cause DNA damage in various cell types. In addition, the inflammatory response induced by chronic infections with pathogens like the microbiota members Helicobacter spp., which have been associated with liver, colorectal, cervical cancers and lymphoma, for instance, can also trigger carcinogenic processes. A microenvironment including active immune cells releasing high amounts of inflammatory signaling molecules can favor the carcinogenic transformation of host cells. Pivotal molecules released during immune response such as the macrophage migration inhibitory factor (MMIF) and the reactive oxygen and nitrogen species' products superoxide and peroxynitrite, can further damage DNA and cause the accumulation of oncogenic mutations, whereas pro-inflammatory cytokines, adhesion molecules, and growth factors may create a microenvironment promoting neoplastic cell survival and proliferation. Recent findings on the implication of inflammatory signaling pathways in microbial-triggered carcinogenesis as well as the possible role of microbiota modulation in cancer prevention are herein summarized and discussed.