In recent years, the relationship between the microbiota and various aspects of health has become a focal point of scientific investigation. Although the most studied microbiota concern the gastrointestinal tract, recently, the interest has also been extended to other body districts. Female genital tract dysbiosis and its possible impact on pathologies such as endometriosis, polycystic ovary syndrome (PCOS), pelvic inflammatory disease (PID), and gynecological cancers have been unveiled. The incursion of pathogenic microbes alters the ecological equilibrium of the vagina, triggering inflammation and compromising immune defense, potentially fostering an environment conducive to cancer development. The most common types of gynecological cancer include cervical, endometrial, and ovarian cancer, which occur in women of any age but especially in postmenopausal women. Several studies highlighted that a low presence of lactobacilli at the vaginal level, and consequently, in related areas (such as the endometrium and ovary), correlates with a higher risk of gynecological pathology and likely contributes to increased incidence and worse prognosis of gynecological cancers. The complex interplay between microbial communities and the development, progression, and treatment of gynecologic malignancies is a burgeoning field not yet fully understood. The intricate crosstalk between the gut microbiota and systemic inflammation introduces a new dimension to our understanding of gynecologic cancers. The objective of this review is to focus attention on the association between vaginal microbiota and gynecological malignancies and provide detailed knowledge for future diagnostic and therapeutic strategies.

Background and Aims: Several studies reported the effect of COVID-19 on inducing gut dysbiosis, which is also correlated with disease severity. This study aims to investigate the effect of a nutraceutical formula on the shift of microbiota profiles and, secondly, on the clinical–pathological parameters of acute and post-acute COVID-19 patients. Methods: In this randomised, double-blind, placebo-controlled trial conducted at National Institute for Infectious diseases (INMI) Lazzaro Spallanzani (Italy), 52 patients were randomly assigned (1:1) to receive a multistrain synbiotic formula (Kebirah^®) or placebo orally for 35 days at COVID-19 diagnosis. Health professionals, investigators, and patients were masked to group assignments. The V3–V4 hypervariable region of 16S rRNA gene sequencing was employed to study the gut microbiota composition in the two groups. Results: Supplementation with Kebirah^® prevented the decrease in the Shannon diversity index of gut microbiota, which was instead observed in patients receiving the placebo. In addition, decreases in lymphocyte count and haemoglobin levels were observed only in the placebo group and not in the treated group, which was also characterised by an amelioration of the gut microbial profile, with an enrichment in beneficial bacteria and a preservation of species diversity. Conclusions: Our data suggest that modulating the gut microbiota in acute disease through administration of a specific symbiotic formula could be a useful strategy in the frame of SARS-CoV-2 infections.

Background and aims: Vaginal microbiomes have been classified into five different general categories, termed Community State Type (CSTs), with CST-III and CST-IV often associated with vaginal dysbiosis which makes women more prone to recurrent infections and assisted reproductive technology (ART) failure. Since a healthy microbiome is one of the key steps for successful reproduction, we investigated the impact of modulating the vaginal microbiota through the oral administration of probiotic formula consisting of a consortium of vaginal-specific lactobacilli and prebiotics (Personal Flora 2^®). Methods: We recruited 32 women who had previous failed IVF cycles and were scheduled to undergo ART. We examined the composition of the vaginal microbiota before and after oral probiotic supplementation using 16S ribosomal RNA (rRNA) sequencing technology. Results: Our data show a noticeable modulation of the vaginal microbiome upon probiotic supplementation. In particular, precision probiotic intervention lowers the species diversity, favoring the dominance of Lactobacillus (p = 0.015) and Bifidobacterium (p = 0.000) whilst decreasing the percentage of Atopobium (p = 0.003), Gardnerella (p = 0.022), and Prevotella (p = 0.000). Conclusions: Although CST-III and CST-IV are generally considered detrimental, gynecologists should not refrain from performing IVF in these women if they have been previously subjected to a consortium of precision probiotics treatments, as the administration of specific probiotics reduces the presence of pathogenic bacteria promoting the increase in lactobacilli associated with a healthy vaginal ecosystem, which could impact pregnancy success.

Seasonality is a key determinant in shaping the composition and function of the human gut microbiota, exerting its influence through multiple interconnected factors. These include seasonal variations in diet, environmental conditions (such as temperature, humidity, and sunlight exposure), behavioral patterns (physical activity, time spent outdoors), and the incidence of seasonal infections. These changes are most visible in certain populations where food availability follows a seasonal pattern. Increasing evidence suggests that gut microbiota composition undergoes seasonal variations, which may have significant implications for human health. In patients with non-communicable chronic diseases (NCDs), where microbiota dysbiosis plays a crucial role in disease progression, understanding the seasonal effects on gut microbiota is essential. These dynamic changes impact the gut microbiota immune system interaction and may contribute to the onset or exacerbation of various diseases, including chronic inflammatory, metabolic, and autoimmune disorders. Most clinical trials on probiotics do not consider seasonality as a confounding variable, which could impact the interpretation of results and therapeutic efficacy, potentially biasing estimates of intervention efficacy or associations with disease. This review examines the current evidence on gut microbiota seasonality, discusses its potential bias, and outlines methodological considerations for future clinical trials.

Recent studies suggest a role for the gut microbiota in the onset, progression, and prognosis of prostate cancer (PCa), one of the most common neoplasms in males. PCa screening relies on PSA testing, whose usefulness remains controversial due to its low specificity. This study was aimed at investigating the differences in the gut microbiota of PCa patients and healthy controls (HCs) and finding correlations between gut microbes and the clinical laboratory parameter assessed in the evaluation of PCa, to identify bacteria which could be used as diagnostic and prognostic biomarkers. Fecal samples collected from 18 PCa patients and 18 HCs were used to isolate bacterial DNA. 16S rRNA gene sequencing provided the gut microbial profiles of the enrolled subjects, whose functional impact was also predicted. A recursive partitioning tree method allowed us to identify a bacterial signature discriminating PCa from HC. A correlation analysis was performed between gut bacteria and the clinical laboratory parameters assessed in the evaluation of PCa. Differential bacterial patterns emerged between PCa patients and HCs, together with significant differences in beta-diversity, alpha-diversity, and richness. The functional prediction of the microbial profiles revealed several metabolic processes differentially regulated, including an enrichment in the Krebs cycle and in steroid hormone synthesis in PCa patients. A bacterial signature based on the abundance of Lactobacillus and Collinsella was found to discriminate between the two groups. Significant correlations were found between gut bacteria and the clinical laboratory parameters generally assessed in the evaluation of PCa. These results indicate that gut microbiota profiles may, in the future, represent potential biomarkers associated with prostate cancer risk or progression; however, further prospective studies and clinical validation are needed before considering their use as diagnostic or prognostic tools.