Ofatumumab is a feasible alternative anti-CD20 therapy in patients intolerant of rituximab

The complement system as a target in cancer immunotherapy

Malignant cells are part of a complex network within the tumor microenvironment, where their interaction with host cells and soluble mediators, including complement components, is pivotal. The complement system, known for its role in immune defense and homeostasis, exhibits a dual effect on cancer progression. This dichotomy arises from its antitumoral opsonophagocytosis and cytotoxicity versus its protumoral chronic inflammation mediated by the C5a/C5aR1 axis, influencing antitumor T-cell responses. Recent studies have revealed distinct co-expression patterns of complement genes in various cancer types, correlating with prognosis. Notably, some cancers exhibit co-regulated overexpression of complement genes associated with poor prognosis, while others show favorable outcomes. However, significant intra-patient heterogeneity further complicates this classification. Moreover, the involvement of locally produced and intracellular complement proteins adds complexity to the tumor microenvironment dynamics. This review highlights the unique interplay of complement components within different cancers and patient cohorts, showing that "one size does not fit all", for complement in cancer. It summarizes the clinical trials for complement targeting in cancer, emphasizing the need for tailored therapeutic approaches. By elucidating the mechanistic basis of complement's context-dependent role, this review aims to facilitate the development of personalized cancer therapies, ultimately improving patient care and outcomes.

Rituximab Therapy for Primary Sjögren's Syndrome

Primary Sjögren's syndrome (pSS) is a systemic autoimmune diseases of the connective tissues, characteristic of the presentation of keratoconjunctivitis sicca and xerostomia. A cardinal pathogenetic feature of SS is B-cell hyperactivity, which has invited efforts on optimal B-cell targeted therapy, whereas conventional corticosteroids and disease-modifying antirheumatic drugs (DMARDs) are restricted to symptomatic relief. As per the first EULAR recommendation for pSS patients published in 2020, regimens with monoclonal antibodies targeting B cells may be initiated in patients with severe, refractory systemic disease, notably rituximab (RTX), a mouse-derived monoclonal antibody that targets CD20 antigen and contributes to B-cell depletion. Nonetheless, the data available from clinical trials with RTX are often controversial. Despite the lack of promising results from two large RCTs, several positive clinical efficacies were demonstrated. This current review addressed the efficacy and safety of clinical trials available and elucidated the potential of RTX on the immune system, especially B and T cells. Furthermore, plausible explanations for the discrepancy in clinical data were also presented.

Multiple Sclerosis and Cancer: The Ying-Yang Effect of Disease Modifying Therapies

Over the past two decades, the field of multiple sclerosis (MS) has been transformed by the rapidly expanding arsenal of new disease modifying therapies (DMTs). Current DMTs for MS aim to modulate innate and adaptive immune responses toward a less inflammatory phenotype. Since the immune system is also critical for identifying and eliminating malignant cells, immunosuppression from DMTs may predictably increase the risk of cancer development in MS patients. Compared with healthy controls, patients with autoimmune conditions, such as MS, may already have a higher risk of developing certain malignancies and this risk may further be magnified by DMT treatments. For those patients who develop both MS and cancer, these comorbid presentations create a challenge for clinicians on how to therapeutically address management of cancer in the context of MS autoimmunity. As there are currently no accepted guidelines for managing MS patients with prior history of or newly developed malignancy, we undertook this review to evaluate the molecular mechanisms of current DMTs and their potential for instigating and treating cancer in patients living with MS.

Clinical practice: hepatitis C virus infection, cryoglobulinemia and cryoglobulinemic vasculitis

Cryoglobulins are circulating immunoglobulins that reversibly precipitate at temperatures below 37 °C. Type-II cryoglobulins consist of monoclonal IgM/polyclonal IgG immune complexes (ICs), whereas in type-III cryoglobulins both IgM and IgG are polyclonal. The clinical condition resulting from the presence of cryoglobulins in the blood is called mixed cryoglobulinemia (MC), which can be asymptomatic or manifest as cryoglobulinemic vasculitis (CV). Type-I cryoglobulins, consisting of a single monoclonal isotype, are detected in patients with lymphoproliferative disorders. It is now established that > 90% of MCs are associated with HCV infection. Clinically, the spectrum of symptoms may range in severity from occasional purpuric eruptions to life-threatening features. In addition to the development of liver cirrhosis and hepatocellular carcinoma, the possible progression of HCV-positive CV patients to B-cell non-Hodgkin lymphoma (B-NHL) has been reported. The pathogenetic role played by HCV infection in the onset of B-NHL is suggested by regression of the latter following the achievement of a sustained virologic response (SVR). For several years, interferon-α alone or combined with ribavirin has been the standard of care. However, the rates of clinical, biochemical, and virologic responses have been low, and the occurrence of relapse frequent. The addition of rituximab has resulted in a higher rate of responses. With the advent of direct-acting antiviral agents, SVR has been achieved in ~ 95% of CV patients. However, in a minority of patients, despite SVR, CV may persist or reappear over variable lengths of time from the completion of therapy. The eventual appearance of B-NHL is also possible.