Rheumatoid arthritis (RA) is a highly prevalent autoimmune disorder. The pathogenesis of the disease is complex and involves various cellular populations, including fibroblast-like synoviocytes, macrophages, and T cells, among others. Identification of signalling pathways and molecules that actively contribute to the development of the disease is crucial to understanding the mechanisms involved in the chronic inflammatory environment present in affected joints. Recent studies have demonstrated that the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway regulates the behaviour of immune cells and contributes to the progression of RA. Several JAK inhibitors, such as tofacitinib, baricitinib, upadacitinib, and filgocitinib, have been developed, and their efficacy and safety in patients with RA have been comprehensively investigated in a number of clinical trials. Consequently, JAK inhibitors have been approved and registered as a treatment for patients with RA. In this review, we discuss the involvement of JAK/STAT signalling in the pathogenesis of RA and summarise the potential beneficial effects of JAK inhibitors in cells implicated in the pathogenesis of the disease. Moreover, we present the most important phase 3 clinical trials that evaluated the use of these agents in patients.

Gastric cancer remains a significant global health challenge, driving the need for innovative therapeutic approaches. Natural polyphenolic compounds such as resveratrol, piceatannol, curcumin, and quercetin currently show promising results in the prevention and treatment of various cancers, due to their diverse biological activities. This review presents the effects of natural compounds on important processes related to cancer, such as apoptosis, proliferation, migration, invasion, angiogenesis, and autophagy. Resveratrol, naturally found in red grapes, has been shown to induce apoptosis and inhibit the proliferation, migration, and invasion of gastric cancer cells. Piceatannol, a metabolite of resveratrol, shares similar anticancer properties, particularly in modulating autophagy. Curcumin, derived from turmeric, is known for its anti-inflammatory and antioxidant properties, and its ability to inhibit tumor growth and metastasis. Quercetin, a flavonoid found in various fruits and vegetables, induces cell cycle arrest and apoptosis while enhancing the efficacy of conventional therapies. Despite their potential, challenges such as low bioavailability limit their clinical application, necessitating further research into novel delivery systems. Collectively, these compounds represent a promising avenue for enhancing gastric cancer treatment and improving patient outcomes through their multifaceted biological effects.

Claudin-18.2 (CLDN18.2) is an isoform of a tight junction protein and has emerged as a promising therapeutic target in gastric cancer (GC). CLDN18.2 is responsible for gastric homeostasis and protects epithelial cells from low pH conditions. Interestingly, CLDN18.2 expression is strictly restricted to the stomach, making it an ideal tumor marker. This narrative review presents the characterization and role of claudin 18.2 (CLDN18.2) as a promising biomarker in GC and a target for clinical therapies, more specifically CLDN18.2-targeted drugs and therapies including mABs (e.g., Zolbetuximab, Osemitamab, ZL-1211), bsAB, and CAR-T cell-based immunotherapies. We also summarize numerous ongoing worldwide clinical trials that are evaluating CLDN18.2 as a target for GC treatment. What seems to be crucial is that preclinical and clinical data indicate their high efficacy and safety.

Due to its rapid progression to advanced stages and highly metastatic properties, gastric cancer (GC) is one of the most aggressive malignancies and the fourth leading cause of cancer-related deaths worldwide. The metastatic process includes local invasion, metastasis initiation, migration with colonisation at distant sites, and evasion of the immune response. Tumour growth involves the activation of inhibitory signals associated with the immune response, also known as immune checkpoints, including PD-1/PD-L1 (programmed death 1/programmed death ligand 1), CTLA-4 (cytotoxic T cell antigen 4), TIGIT (T cell immunoreceptor with Ig and ITIM domains), and others. Immune checkpoint molecules (ICPMs) are proteins that modulate the innate and adaptive immune responses. While their expression is prominent on immune cells, mainly antigen-presenting cells (APC) and other types of cells, they are also expressed on tumour cells. The engagement of the receptor by the ligand is crucial for inhibiting or stimulating the immune cell, which is an extremely important aspect of cancer immunotherapy. This narrative review explores immunotherapy, focusing on ICPMs and immune checkpoint inhibitors in GC. We also summarise the current clinical trials that are evaluating ICPMs as a target for GC treatment.

Atherosclerosis is a condition that is associated with lipid accumulation in the arterial intima. Consequently, the enlarging lesion, which is also known as an atherosclerotic plaque, may close the blood vessel lumen, thus leading to organ ischaemia. Furthermore, the plaque may rupture and initiate the formation of a thrombus, which can cause acute ischaemia. Atherosclerosis is a background pathological condition that can eventually lead to major cardiovascular diseases such as acute coronary syndrome or ischaemic stroke. The disorder is associated with an altered profile of alarmins, stress response molecules that are secreted due to cell injury or death and that induce inflammatory responses. High-mobility group box 1 (HMGB1), S100 proteins, interleukin-33, and heat shock proteins (HSPs) also affect the behaviour of endothelial cells and vascular smooth muscle cells (VSMCs). Thus, alarmins control the inflammatory responses of endothelial cells and proliferation of VSMCs, two important processes implicated in the pathogenesis of atherosclerosis. In this review, we will discuss the role of alarmins in the pathophysiology of atherosclerosis and myocardial infarction.

Extracellular vesicles (EVs) are membrane-bound structures released by cells that contain bioactive cargo such as cytokines or non-coding RNA. It is widely known that EVs influence the activity of other cells; they take part in the pathogenesis and compensatory mechanisms of multiple diseases. Frequently, EVs can share the properties of their source cells, thus allowing the use of EVs as non-cellular vectors or therapeutic agents. Importantly, these structures can express the ligand for the programmed cell death protein 1 (PD-L1). It binds to the PD-1 protein present on the immune cells, which suppresses the activity of T cells. The PD-1/PD-L1 axis is widely known in the field of oncology, as PD-L1 present on the surface of cancer cells inhibits cytotoxic activity of T cells, thus promoting cancer growth and treatment resistance. Immunotherapy prevents PD-1/PD-L1 binding and restores anticancer properties of the immune cells. By contrast, the above-mentioned binding is desired in the context of autoimmunity, where abnormal activity of immune cells is a hallmark element in the pathogenesis of these conditions. The aim of this review is to present and discuss the latest findings regarding the role of EVs-PD-L1 in cancer and autoimmunity.