Mihai Andrei Cosovanu

Colorectal cancer (CRC), a prevalent malignancy, is a significant global health concern. The intricate interplay of genetic mutations, inflammatory processes, and environmental factors underscores the complexity of CRC’s etiology. The human gut harbors a diverse microbial community that plays a key role in maintaining homeostasis and influencing various aspects of host physiology. Perturbations in the gut microbiome (GM) composition and function have been implicated in CRC carcinogenesis. This bidirectional relationship involves microbial contributions to inflammation, DNA damage, and immune modulation, shaping the tumor microenvironment (TME). Bacteriophages, viruses that infect bacteria, contribute to the microbiome’s diversity and function by influencing bacterial abundance and composition. These phages can impact host–microbiome interactions, potentially influencing CRC risk. Furthermore, they can be manipulated to transport targeted medication, without being metabolized. Antibiotics exert selective pressures on the gut microbiome, leading to shifts in bacterial populations and potential dysbiosis. Probiotics can modulate the composition and activity of the GM and could be considered adjunctive therapy in the treatment of CRC. Understanding the intricate balance between bacteriophages, antibiotics–probiotics, and the GM is essential for comprehending CRC etiology and progression.

Autoimmune dermatological diseases (AIDD) encompass a diverse group of disorders characterized by aberrant immune responses targeting the skin and its associated structures. In recent years, emerging evidence suggests a potential involvement of the renin–angiotensin system (RAS) in the pathogenesis and progression of these conditions. RAS is a multicomponent cascade, primarily known for its role in regulating blood pressure and fluid balance. All of the RAS components play an important role in controlling inflammation and other immune responses. Angiotensin II, the main effector, acts on two essential receptors: Angiotensin Receptor 1 and 2 (AT1R and AT2R). A disturbance in the axis can lead to many pathological processes, including autoimmune (AI) diseases. AT1R activation triggers diverse signaling cascades involved in inflammation, fibrosis and tissue remodeling. Experimental studies have demonstrated the presence of AT1R in various cutaneous cells and immune cells, further emphasizing its potential contribution to the AI processes in the skin. Furthermore, recent investigations have highlighted the role of other RAS components, beyond angiotensin-converting enzyme (ACE) and Ang II, that may contribute to the pathophysiology of AIDD. Alternative pathways involving ACE2, Ang receptors and Ang-(1-7) have been implicated in regulating immune responses and tissue homeostasis within the skin microenvironment. Understanding the intricate involvement of the RAS in AIDD may provide novel therapeutic opportunities. Targeting specific components of the RAS, such as angiotensin receptor blockers (ARBs), ACE inhibitors (ACEIs) or alternative RAS pathway modulators, could potentially ameliorate inflammatory responses, reduce tissue damage and lessen disease manifestations. Further research is warranted to outline the exact mechanisms underlying RAS-mediated immune dysregulation in AIDD. This abstract aims to provide a concise overview of the intricate interplay between the RAS and AIDD. Therefore, we elaborate a systematic review of the potential challenge of RAS in the AIDD, including psoriasis, systemic sclerosis, vitiligo, lupus erythematosus and many more.