Microbiota, Oxidative Stress, and Skin Cancer: An Unexpected Triangle

Unveiling the intratumoral microbiota within cancer landscapes

Recent advances in cancer research have unveiled a significant yet previously underappreciated aspect of oncology: the presence and role of intratumoral microbiota. These microbial residents, encompassing bacteria, fungi, and viruses within tumor tissues, have been found to exert considerable influence on tumor development, progression, and the efficacy of therapeutic interventions. This review aims to synthesize these groundbreaking discoveries, providing an integrated overview of the identification, characterization, and functional roles of intratumoral microbiota in cancer biology. We focus on elucidating the complex interactions between these microorganisms and the tumor microenvironment, highlighting their potential as novel biomarkers and therapeutic targets. The purpose of this review is to offer a comprehensive understanding of the microbial dimension in cancer, paving the way for innovative approaches in cancer diagnosis and treatment.

Pathogenic mechanisms and etiologic aspects of Mycobacterium avium subspecies paratuberculosis as an infectious cause of cutaneous melanoma

Infectious etiologies have previously been proposed as causes of both melanoma and non-melanoma skin cancer. This exploratory overview explains and presents the evidence for the hypothesis that a microorganism excreted in infected ruminant animal feces, Mycobacterium avium subspecies paratuberculosis (MAP), is the cause of some cases of cutaneous melanoma (CM). Occupational, residential, and recreational contact with MAP-contaminated feces, soil, sand, and natural bodies of water may confer a higher rate of CM. Included in our hypothesis are possible reasons for the differing rates and locations of CM in persons with white versus nonwhite skin, why CM develops underneath nails and in vulvar skin, why canine melanoma is an excellent model for human melanoma, and why the Bacille Calmette-Guérin (BCG) vaccine has demonstrated efficacy in the prevention and treatment of CM. The pathogenic mechanisms and etiologic aspects of MAP, as a transmittable agent underlying CM risk, are carefully deliberated in this paper. Imbalances in gut and skin bacteria, genetic risk factors, and vaccine prevention/therapy are also discussed, while acknowledging that the evidence for a causal association between MAP exposure and CM remains circumstantial.

Therapeutic textiles: A promising approach for human skin dysbiosis?

The close interaction between skin and clothing has become an attractive cornerstone for the development of therapeutic textiles able to alleviate skin disorders, namely those correlated to microbiota dysregulation. Skin microbiota imbalance is known in several skin diseases, including atopic dermatitis (AD), psoriasis, seborrheic dermatitis, rosacea, acne and hidradenitis suppurative (HS). Such microbiota dysregulation is usually correlated with inflammation, discomfort and pruritus. Although conventional treatments, that is, the administration of steroids and antibiotics, have shown some efficacy in treating and alleviating these symptoms, there are still disadvantages that need to be overcome. These include their long-term usage with side effects negatively impacting resident microbiota members, antibiotic resistance and the elevated rate of recurrence. Remarkably, therapeutic textiles as a non-pharmacological measure have emerged as a promising strategy to treat, alleviate the symptoms and control the severity of many skin diseases. This systematic review showcases for the first time the effects of therapeutic textiles on patients with skin dysbiosis, focusing on efficacy, safety, adverse effects and antimicrobial, antioxidant and anti-inflammatory properties. The main inclusion criteria were clinical trials performed in patients with skin dysbiosis who received treatment involving the use of therapeutic textiles. Although there are promising outcomes regarding clinical parameters, safety and adverse effects, there is still a lack of information about the impact of therapeutic textiles on the skin microbiota of such patients. Intensive investigation and corroboration with clinical trials are needed to strengthen, define and drive the real benefit and the ideal biomedical application of therapeutic textiles.

The Critical Role of Pyroptosis in Peri-Implantitis

Background

Peri-implantitis (PI) is a prevalent complication of implant treatment. Pyroptosis, a distinctive inflammatory programmed cell death, is crucial to the pathophysiology of PI. Despite its importance, the pyroptosis-related genes (PRGs) influencing PI's progression remain largely unexplored.

Methods

This study conducted histological staining and transcriptome analyze from three datasets. The intersection of differentially expressed genes (DEGs) and PRGs was identified as pyroptosis-related differentially expressed genes (PRDEGs). Functional enrichment analyses were conducted to shed light on potential underlying mechanisms. Weighted Gene Co-expression Network Analysis (WGCNA) and a pyroptotic macrophage model were utilized to identify and validate hub PRDEGs. Immune cell infiltration in PI and its relationship with hub PRDEGs were also examined. Furthermore, consensus clustering was performed to identify new PI subtypes. Protein-protein interaction (PPI) network, competing endogenous RNA (ceRNA) network, mRNA-mRNA binding protein regulatory (RBP) network, and mRNA-drugs regulatory network of hub PRDEGs were also analyzed.

Results

Eight hub PRDEGs were identified: PGF, DPEP1, IL36B, IFIH1, TCEA3, RIPK3, NET7, and TLR3, which are instrumental in the PI's progression. Two PI subtypes were distinguished, with Cluster 1 exhibiting higher immune cell activation. The exploration of regulatory networks provided novel mechanisms and therapeutic targets in PI.

Conclusion

Our research highlights the critical role of pyroptosis and identifies eight hub PRDEGs in PI's progression, offering insights into novel immunotherapy targets and laying the foundation for advanced diagnostic and treatment strategies. This contributes to our understanding of PI and underscores the potential for personalized clinical management.

Plaque Psoriasis Exacerbation and COVID-19 Vaccination: Assessing the Characteristics of the Flare and the Exposome Parameters

The diverse patient population and widespread vaccination in the COVD-19 era make vaccine-triggered episodes of psoriasis an ideal model of exposome research. This scenario explores the fine balance between protective and exacerbating factors, providing insights into the complex relationship between environmental exposure and psoriasis immunopathogenesis when a trigger appears, such as that of the hyperinflammatory state induced by the COVID-19 vaccine. Analyzing interactions between vaccine-induced phenomena and exposome parameters may provide clinically relevant information important for personalized medicine decision-making. We performed a literature review seeking patients with plaque psoriasis flares or new onset or change in plaque psoriasis into another psoriasis subtype, such as pustular or erythrodermic flare, focusing on the inner and external exposome traits of patients. We identified 71 patients with plaque psoriasis flares, 12 patients with new-onset psoriasis, and 17 with plaque psoriasis subtype change, and assessed the COVID-19 vaccine-induced plaque psoriasis in terms of clinical presentation, post-vaccination flare period and treatment status, as well as inner exposome parameters (genomics, oxidative stress, hormonal impact due to gender, aging, skin color) and external parameters (UV, infectomics). Novel data on psoriasis flares following COVID-19 vaccination are primarily obtained by combining exposome and vaccine-triggered episode features and characteristics and comparing them with similar psoriasis flares unrelated to COVID-19 vaccination.

Biological evaluations and computational studies of newly synthesized thymol-based Schiff bases as anticancer, antimicrobial and antioxidant agents

Three new thymol-based molecules were synthesized and evaluated as anticancer, antimicrobial and antioxidant agents. Liver, colon, lung and prostate cancer cell lines were utilized in cytotoxicity tests. The results demonstrated that synthesized molecules had a cytotoxic effect against the screened cell lines. One of the molecules (4a) was found to have a higher efficacy towards the colon cancer cell line (DLD-1) with an IC50 value of 12.39 µM and the other (4c) towards the prostate cancer cell line (PC3) with an IC50 value of 7.67 µM than the positive control drug cisplatin. To assess the antimicrobial activity of molecules (4a-c), Gram-positive bacteria, Gram-negative bacteria and yeast were subjected to agar disc diffusion and broth microdilution assays. The investigation of antioxidant potential was conducted using the DPPH radical scavenging activity assay. While all compounds displayed strong cytotoxic and antioxidant properties, they exhibited only moderate antimicrobial activity. Molecular docking studies were performed on epidermal growth factor receptor (EGFR), vascular endothelial growth factor receptor 2 (VEGFR-2), focal adhesion kinase (FAK), B-Raf and phosphoinositide 3-kinase (PI3K). The binding energies and interactions obtained from the docking results of compounds (4a-c) supported the experimental results. Drug similarity rates and pharmacokinetic properties were analyzed with the absorption, distribution, metabolism and excretion (ADME) method. Geometric parameters such as chemical potential (µ), electrophilicity index (ω) and chemical softness (σ) of compounds (4a-c) were calculated using the 6-31*G basis set B3LYP method.Communicated by Ramaswamy H. Sarma.

Role of the Microbiota in Skin Neoplasms: New Therapeutic Horizons

The skin and the gut are regularly colonized by a variety of microorganisms capable of interacting with the immune system through their metabolites and influencing the balance between immune tolerance and inflammation. Alterations in the composition and diversity of the skin microbiota have been described in various cutaneous diseases, including skin cancer, and the actual function of the human microbiota in skin carcinogenesis, such as in progression and metastasis, is currently an active area of research. The role of Human Papilloma Virus (HPV) in the pathogenesis of squamous cell carcinoma is well consolidated, especially in chronically immunosuppressed patients. Furthermore, an imbalance between Staphylococcus spp., such as Staphylococcus epidermidis and aureus, has been found to be strongly related to the progression from actinic keratosis to squamous cell carcinoma and differently associated with various stages of the diseases in cutaneous T-cell lymphoma patients. Also, in melanoma patients, differences in microbiota have been related to dissimilar disease course and prognosis and may affect the effectiveness and tolerability of immune checkpoint inhibitors, which currently represent one of the best chances of a cure. From this point of view, acting on microbiota can be considered a possible therapeutic option for patients with advanced skin cancers, even if several issues are still open.