Rheumatoid arthritis and lymphatic cancer

Identification and Verification of Novel Biomarkers Involving Rheumatoid Arthritis with Multimachine Learning Algorithms: An In Silicon and In Vivo Study

Background

Rheumatoid arthritis (RA) remains one of the most prevalent chronic joint diseases. However, due to the heterogeneity among RA patients, there are still no robust diagnostic and therapeutic biomarkers for the diagnosis and treatment of RA.

Methods

We retrieved RA-related and pan-cancer information datasets from the Gene Expression Omnibus and The Cancer Genome Atlas databases, respectively. Six gene expression profiles and corresponding clinical information of GSE12021, GSE29746, GSE55235, GSE55457, GSE77298, and GSE89408 were adopted to perform differential expression gene analysis, enrichment, and immune component difference analyses of RA. Four machine learning algorithms, including LASSO, RF, XGBoost, and SVM, were used to identify RA-related biomarkers. Unsupervised cluster analysis was also used to decipher the heterogeneity of RA. A four-signature-based nomogram was constructed and verified to specifically diagnose RA and osteoarthritis (OA) from normal tissues. Consequently, RA-HFLS cell was utilized to investigate the biological role of CRTAM in RA. In addition, comparisons of diagnostic efficacy and biological roles among CRTAM and other classic biomarkers of RA were also performed.

Results

Immune and stromal components were highly enriched in RA. Chemokine- and Th cell-related signatures were significantly activated in RA tissues. Four promising and novel biomarkers, including CRTAM, PTTG1IP, ITGB2, and MMP13, were identified and verified, which could be treated as novel treatment and diagnostic targets for RA. Nomograms based on the four signatures might aid in distinguishing and diagnosing RA, which reached a satisfactory performance in both training (AUC = 0.894) and testing (AUC = 0.843) cohorts. Two distinct subtypes of RA patients were identified, which further verified that these four signatures might be involved in the immune infiltration process. Furthermore, knockdown of CRTAM could significantly suppress the proliferation and invasion ability of RA cell line and thus could be treated as a novel therapeutic target. CRTAM owned a great diagnostic performance for RA than previous biomarkers including MMP3, S100A8, S100A9, IL6, COMP, LAG3, and ENTPD1. Mechanically, CRTAM could also be involved in the progression through immune dysfunction, fatty acid metabolism, and genomic instability across several cancer subtypes.

Conclusion

CRTAM, PTTG1IP, ITGB2, and MMP13 were highly expressed in RA tissues and might function as pivotal diagnostic and treatment targets by deteriorating the immune dysfunction state. In addition, CRTAM might fuel cancer progression through immune signals, especially among RA patients.

Malignant lymphoma associated with rheumatoid arthritis, developing shortly after initiation of oral methotrexate

We report a patient with rheumatoid arthritis (RA) who developed malignant lymphoma of the diffuse large B-cell type in the right submandibular region shortly after initiation of oral methotrexate (MTX). Despite cessation of MTX, the lymphadenopathy did not regress, and only reached complete remission after 3 courses of CHOP therapy followed by irradiation. In this patient highly active RA itself was considered to be the main cause of malignant lymphoma, and MTX might have contributed to the development by modifying the immune system. When RA is highly active, MTX should be used carefully because of the possible development of malignant lymphoma as well as other serious complications.

Co-morbidity in rheumatoid arthritis

Rheumatoid arthritis (RA) affects approximately 0.5-1% of the population and imposes substantial societal costs including an increased risk of work-related disability and accelerated mortality. It is increasingly clear that RA-related co-morbidities, including cardiovascular disease (CVD), infection, osteoporosis, lymphoproliferative malignancy, and peptic ulcer disease, serve as major determinants of disease-associated outcome. In this review, the impact of these select co-morbidities on RA outcome is discussed. In addition, this review explores potential mechanisms underlying their association with RA, the possible iatrogenic role of agents used to treat the disease, and measures aimed at both prevention and treatment of disease-specific co-morbidity.

Remission of lymphoma after drug withdrawal in rheumatoid arthritis

A 63-year-old man with rheumatoid arthritis presented with pain and swelling of his right buttock. Imaging and tissue biopsy revealed a diffuse large B-cell, non-Hodgkin's lymphoma. The disease-modifying drugs he was taking, cyclosporin and methotrexate, were stopped, and the lymphoma resolved spontaneously without the use of chemotherapy.

The dual association between lymphoma and autoimmunity

Autoimmune rheumatic diseases and lymphocytic malignancies are related and this association is bidirectional. Lymphomas occur more frequently in the course of autoimmune disease and autoimmune rheumatic manifestations occur in the course of lymphocytic malignancies. An increased incidence of malignant lymphocytic diseases is present in patients with rheumatoid arthritis, systemic lupus erythematosus, Sjögren's syndrome, and autoimmune thyroid disease. Descriptions of lymphocytic malignancies among other autoimmune rheumatic disease have been published. In some patients, the malignant disease is diagnosed months or years before the appearance of the rheumatic disease.

Comorbidity in rheumatoid arthritis

It is increasingly clear that coexistent disease plays a pivotal role in RA outcome and that efforts aimed at specifically addressing these comorbidities need to be aggressively sought, investigated, and implemented once proven effective. RA-associated costs are currently increasing at twice the rate of the medical care index. Comorbidity in the setting of RA independently predicts disease-associated disability (a major cost component) and mortality, underscoring the need for a more comprehensive approach to RA, one that adequately addresses disease-specific comorbidities. At present, many primary and secondary preventative measures (Table 1) for RA-specific comorbidities remain largely unproved and require rigorous investigation in a randomized prospective fashion. Despite this ongoing need, advances are being made in our understanding of the underlying pathogenesis of these comorbid conditions and their relation with RA. This improved understanding should translate into further effective interventions. Bisphosphonates, for instance, have been shown to be effective in the prevention of GIOP and associated fractures. The past several years have seen other exciting therapeutic advances in RA. DMARD combinations have been shown to be more effective and no more toxic than MTX monotherapy. In addition to the recent release of COX-2 NSAIDs, three new disease-modifying agents (leflunomide, etanercept, and infliximab) have been added to the therapeutic armamentarium; these are options that have markedly changed the treatment landscape in RA. Although these important advances have generated much deserved optimism, the precise effect that these agents may have on RA-specific comorbidity remains to be seen. The next decade should prove to be an exciting time in RA management. Better identification, understanding, and management of RA comorbidities have great potential to improve quality of life and survival among our patients with RA.

Medical history and risk of Hodgkin's and non-Hodgkin's lymphomas

The relationship between a history of selected medical conditions and risk of lymphomas was investigated in a hospital-based case-control study conducted in Northern Italy on 429 incident, histologically confirmed cases of non-Hodgkin's lymphoma (NHL), 158 cases of Hodgkin's disease (HD) and 1157 controls admitted to hospitals for acute conditions. The odds ratios (OR) for NHL were above unity in patients with a history of infectious mononucleosis (OR 2.9), herpes zoster (OR 1.8), pyelonephritis (OR 4.9), tuberculosis (OR 1.8), malaria (OR 1.9), any chronic bacterial diseases (OR 1.7), rheumatoid arthritis (OR 1.7) and psoriasis (OR 2.5). With reference to HD, the ORs were 4.0 for infectious mononucleosis, 2.9 for herpes zoster, 3.3 for pyelonephritis, 2.3 for tuberculosis, 1.4 for chronic bacterial diseases, 2.4 for rheumatoid arthritis, 2.7 for psoriasis and 2.1 for diabetes. The association of NHL and HD with herpes zoster was restricted to the first ten years since the onset of the disease. The relationships between NHL and mononucleosis (OR 12.9), malaria (OR 2.8) and psoriasis (OR 14.0) were stronger for cases aged > or = 60 years, and that with tuberculosis (OR 3.5) was stronger for younger cases. For HD, the positive association was stronger for cases aged > or = 40 years for herpes zoster (OR 3.8) and diabetes (OR 2.6). An increased risk of NHL was found in association with poliomyelitis (OR 1.6) (restricted to cases aged > or = 60 years, OR 4.0) and BCG immunizations (OR 1.6), but not with vaccination against smallpox, tetanus and diphtheria; increased risks of HD were found in relation to poliomyelitis and BCG immunization in cases aged > or = 40 years (OR respectively 2.5 and 2.1), or > or = 50 years (OR 4.3 and 2.2). Thus, our results confirm the association between a history of several chronic infectious and inflammatory diseases and the risk of NHL or HD, and are compatible with a role of chronic immunological alterations in the aetiology of lymphomas.

The incidence of cancer associated with the treatment of rheumatoid arthritis

OBJECTIVES

The treatment of rheumatoid arthritis (RA) targets inflammation either by inhibiting the activation of immune cells or their clonal expansion. We evaluated the available evidence concerning the risk of cancer associated with RA treatment.

METHOD

Articles published between 1966 and 1998 reporting the incidence of cancer in RA patients were reviewed.

RESULTS

Large follow-up studies suggest the relative risk (RR) of lymphomas associated with RA is about twofold higher than in the general population. A role for azathioprine in the development of lymphomas and a role for cyclophosphamide in cancers, particularly bladder cancer, has been suggested. However, no studies have shown that methotrexate increases the risk of cancer in RA patients. Studies that showed an increased risk of cancer associated with gold or cyclosporine therapy in RA patients are inconclusive as they have used cancer incidence in the general population as the reference. One study measured the RR of cancer in a group of cyclosporine-treated RA patients (1.6 year on average) using RA patients as a control and found no enhanced risk.

CONCLUSIONS

Although evidence suggests an increased risk of specific cancers associated with the use of some treatments, this may be outweighed by the potential benefit of therapy, especially in patients with severe disease.