Oral-Gut-Estrobolome Axis May Exert a Selective Impact on Oral Cancer.

A subset of bacterial species that holds genes encoding for ß-glucuronidase and ß-galactosidase, enzymes involved in the metabolism of conjugated estrogens, is called the "estrobolome." There is an emerging interest embracing this concept, as it may exert a selective impact on a number of pathologies, including oral cancer. Although the estrobolome bacteria are typically part of the gut microbiota, recent experimental pieces of evidence have suggested a crosstalk among oral and gut microbiota. In fact, several oral bacterial species are well represented also in the gut microbiota, and these microbes can effectively induce the estrobolome activation. The main pathways used for activating the estrobolome are based on the induction of the expression patterns for 2 bacterial enzymes: ß-glucuronidase and aromatase, both involved in the increase of estrogen released in the bloodstream and consequently in the salivary compartment. Mechanistically, high estrogen availability in saliva is responsible for an increase in oral cancer risk for different reasons: briefly, 1) estrogens directly exert biological and metabolic effects on oral mucosa cells; 2) they can modulate the pathological profile of some bacteria, somewhere associated with neoplastic processes (i.e., Fusobacterium spp., Parvimonas ssp.); and 3) some oral bacteria are able to convert estrogens into carcinogenic metabolites, such as 4-hydroxyestrone and 16α-hydroxyestrone (16α-OHE), and can also promote local and systemic inflammation. Nowadays, only a small number of scientific studies have taken into consideration the potential correlations among oral dysbiosis, alterations of the gut estrobolome, and some hormone-dependent cancers: this lack of attention on such a promising topic could be a bias affecting the full understanding of the pathogenesis of several estrogen-related oral pathologies. In our article, we have speculated on the activity of an oral-gut-estrobolome axis, capable of synergizing these 2 important microbiotas, shedding light on a pilot hypothesis requiring further research.

Oral bisphosphonate-induced osteonecrosis complications in patients undergoing tooth extraction: a systematic review and literature updates.

OBJECTIVE: Bisphosphonates, the most common anti-resorptive medications, are internalized by osteoclasts, where they inhibit the macrophage colony-stimulating factor (M-CSF) pathway, preventing their differentiation, inhibiting anchorage to the cell membrane, and inducing apoptosis. In patients undergoing oral bisphosphonate therapy, oral surgery involves a high risk of developing drug-related osteonecrosis of the jaws (BRONJ/MRONJ), among the possible complications. MATERIALS AND METHODS: A systematic search was carried out on the PubMed, Scopus and Cochrane Library search engines, using the keywords "oral bisphosphonates AND tooth extraction", "third molar extraction AND oral bisphosphonates". In addition, we manually evaluated the articles included in references from other sources and an analysis of the Gray Literature was performed. A secondary outcome was to evaluate the assessment of pharmacological (antibiotics) use in the BRONJ/MRONJ management. The revision protocol followed the indications of the Cochrane Handbook, and was registered in the INPLASY database, while the drafting of the manuscript was based on PRISMA. RESULTS: The results of the systematic review, after the study identification and selection process, included a total of 7 studies: 4 retrospective studies, 2 prospective studies and 1 case report. The main complication was represented by osteonecrosis of the jaws, which appears to be related to the duration of treatment with bisphosphonates; in addition, data regarding the anatomical location of post-extraction sites, the sex and age of patients, comorbidities and various systemic risk factors were extrapolated. The most frequent post-extraction complication in patients treated with oral bisphosphonates is osteonecrosis of the jaws, with a significant prevalence in the posterior region of the mandible. In some cases, delayed healing of the surgical wound was also found; moreover, the duration of exposure to oral bisphosphonates influences the onset of complications. CONCLUSIONS: Ongoing studies continue to unravel the role of the oral environment response in alveolar bone homeostasis and how it might contribute to the induction of BRONJ/MRONJ. Approaching the problem from this perspective could provide new directions for the prevention of BRONJ/MRONJ and expand our understanding of the unique oral microenvironment.

Evaluation of the ideal vaginal Progesterone effectiveness doses for luteal support in embryo thawing cycles after endometrial preparation without using the GnRh analogue.

OBJECTIVE: Frozen-thawed embryo transfer (FET) cycles require the use of luteal phase support (LPS) for supporting implantation, endometrial and embryo maturity. Individualized LPS should be chosen according to the used endometrial preparation protocol. The aim of the study was to analyze the effectiveness of two different vaginal Progesterone doses for women who underwent FET cycle and the same endometrial preparation without using the GnRh analogue. PATIENTS AND METHODS: 607 women who underwent FET cycle were included in the study. 305 patients received luteal support with 600 mg/day vaginal Progesterone and 302 patients were treated with 800 mg/day of vaginal Progesterone. RESULTS: In the 800 mg/day group, the mean serum Progesterone concentration on the day of embryo transfer was higher than in the 600 mg group (14.00±6.18 ng/mL and 12.22±5.39, respectively, p < 0.001). Moreover, human chorionic gonadotrophin (hCG) positive and ongoing pregnancy rates were higher in the group of patients who received LPS with 800 mg/day of Progesterone than in the group of patients treated with 600 mg/day of Progesterone.  CONCLUSIONS: In patients undergoing FET cycles following endometrial preparation made without previously using the GnRh analogue, 800 mg doses of vaginal Progesterone as LPS improve reproductive outcomes.