Human oral mucosa cell atlas reveals a stromal-neutrophil axis regulating tissue immunity.

The oral mucosa remains an understudied barrier tissue. This is a site of rich exposure to antigens and commensals, and a tissue susceptible to one of the most prevalent human inflammatory diseases, periodontitis. To aid in understanding tissue-specific pathophysiology, we compile a single-cell transcriptome atlas of human oral mucosa in healthy individuals and patients with periodontitis. We uncover the complex cellular landscape of oral mucosal tissues and identify epithelial and stromal cell populations with inflammatory signatures that promote antimicrobial defenses and neutrophil recruitment. Our findings link exaggerated stromal cell responsiveness with enhanced neutrophil and leukocyte infiltration in periodontitis. Our work provides a resource characterizing the role of tissue stroma in regulating mucosal tissue homeostasis and disease pathogenesis.

Co-optation of Tandem DNA Repeats for the Maintenance of Mesenchymal Identity.

Tandem repeats (TRs) are generated by DNA replication errors and retain a high level of instability, which in principle would make them unsuitable for integration into gene regulatory networks. However, the appearance of DNA sequence motifs recognized by transcription factors may turn TRs into functional cis-regulatory elements, thus favoring their stabilization in genomes. Here, we show that, in human cells, the transcriptional repressor ZEB1, which promotes the maintenance of mesenchymal features largely by suppressing epithelial genes and microRNAs, occupies TRs harboring dozens of copies of its DNA-binding motif within genomic loci relevant for maintenance of epithelial identity. The deletion of one such TR caused quasi-mesenchymal cancer cells to reacquire epithelial features, partially recapitulating the effects of ZEB1 gene deletion. These data demonstrate that the high density of identical motifs in TRs can make them suitable platforms for recruitment of transcriptional repressors, thus promoting their exaptation into pre-existing cis-regulatory networks.

ILC1: guardians of the oral mucosa against enemy viruses.

Type 1 innate lymphoid cells (ILC1s) regulate inflammation in the tissues; however, their role in anti-viral immunity remains largely unknown. In this issue of Immunity, Shannon et al. report that ILC1s invoke an anti-viral effect by producing interferon (IFN)γ at homeostasis, thereby limiting viral replication in the oral mucosa.

The broadening scope of oral mucositis and oral ulcerative mucosal toxicities of anticancer therapies.

Oral mucositis (OM) is a common, highly symptomatic complication of cancer therapy that affects patients' function, quality of life, and ability to tolerate treatment. In certain patients with cancer, OM is associated with increased mortality. Research on the management of OM is ongoing. Oral mucosal toxicities are also reported in targeted and immune checkpoint inhibitor therapies. The objective of this article is to present current knowledge about the epidemiology, pathogenesis, assessment, risk prediction, and current and developing intervention strategies for OM and other ulcerative mucosal toxicities caused by both conventional and evolving forms of cancer therapy.

On-going Mechanical Damage from Mastication Drives Homeostatic Th17 Cell Responses at the Oral Barrier.

Immuno-surveillance networks operating at barrier sites are tuned by local tissue cues to ensure effective immunity. Site-specific commensal bacteria provide key signals ensuring host defense in the skin and gut. However, how the oral microbiome and tissue-specific signals balance immunity and regulation at the gingiva, a key oral barrier, remains minimally explored. In contrast to the skin and gut, we demonstrate that gingiva-resident T helper 17 (Th17) cells developed via a commensal colonization-independent mechanism. Accumulation of Th17 cells at the gingiva was driven in response to the physiological barrier damage that occurs during mastication. Physiological mechanical damage, via induction of interleukin 6 (IL-6) from epithelial cells, tailored effector T cell function, promoting increases in gingival Th17 cell numbers. These data highlight that diverse tissue-specific mechanisms govern education of Th17 cell responses and demonstrate that mechanical damage helps define the immune tone of this important oral barrier.

Individual-specific levels of CTG•CAG somatic instability are shared across multiple tissues in myotonic dystrophy type 1.

Myotonic dystrophy type 1 is a complex disease caused by a genetically unstable CTG repeat expansion in the 3'-untranslated region of the DMPK gene. Age-dependent, tissue-specific somatic instability has confounded genotype-phenotype associations, but growing evidence suggests that it also contributes directly toward disease progression. Using a well-characterized clinical cohort of DM1 patients from Costa Rica, we quantified somatic instability in blood, buccal cells, skin and skeletal muscle. Whilst skeletal muscle showed the largest expansions, modal allele lengths in skin were also very large and frequently exceeded 2000 CTG repeats. Similarly, the degree of somatic expansion in blood, muscle and skin were associated with each other. Notably, we found that the degree of somatic expansion in skin was highly predictive of that in skeletal muscle. More importantly, we established that individuals whose repeat expanded more rapidly than expected in one tissue (after correction for progenitor allele length and age) also expanded more rapidly than expected in other tissues. We also provide evidence suggesting that individuals in whom the repeat expanded more rapidly than expected in skeletal muscle have an earlier age at onset than expected (after correction for the progenitor allele length). Pyrosequencing analyses of the genomic DNA flanking the CTG repeat revealed that the degree of methylation in muscle was well predicted by the muscle modal allele length and age, but that neither methylation of the flanking DNA nor levels of DMPK sense and anti-sense transcripts could obviously explain individual- or tissue-specific patterns of somatic instability.

RFX transcription factor in the human-associated yeast Candida albicans regulates adhesion to oral epithelium.

Adhesion to mucosal surfaces is a critical step in many bacterial and fungal infections. Here, using a mouse model of oral infection by the human fungal pathobiont Candida albicans, we report the identification of a novel regulator of C. albicans adhesion to the oral mucosa. The regulator is a member of the regulatory factor X (RFX) family of transcription factors, which control cellular processes ranging from genome integrity in model yeasts to tissue differentiation in vertebrates. Mice infected with the C. albicans rfx1 deletion mutant displayed increased fungal burden in tongues compared to animals infected with the reference strain. High-resolution imaging revealed RFX1 transcripts being expressed by C. albicans cells during infection. Concomitant with the increase in fungal burden, the rfx1 mutant elicited an enhanced innate immune response. Transcriptome analyses uncovered HWP1, a gene encoding an adhesion protein that mediates covalent attachment to buccal cells, as a major RFX1-regulated locus. Consistent with this result, we establish that C. albicans adhesion to oral cells is modulated by RFX1 in an HWP1-dependent manner. Our findings expand the repertoire of biological processes controlled by the RFX family and illustrate a mechanism whereby C. albicans can adjust adhesion to the oral epithelium.

Oral mucosa effectively protects against peanut allergy in mice.

BACKGROUND: Oral consumption of peanut products early in life reduces the incidence of peanut allergy in children. However, little is known about whether exposure via the oral mucosa alone is sufficient or whether the gastrointestinal tract must be engaged to protect against peanut allergy. OBJECTIVE: We used a mouse model and examined the effects of peanut allergen administration to only the oral cavity on allergy development induced by environmental exposure. METHODS: Naive BALB/c mice were administered peanut flour (PNF) sublingually, followed by epicutaneous exposure to PNF to mimic a human condition. The sublingual volume was adjusted to engage only the oral cavity and prevent it from reaching the esophagus or gastrointestinal tract. The efficacy was evaluated by examining the anaphylactic response, antibody titers, and T follicular helper cells. RESULTS: The mice exposed epicutaneously to PNF developed peanut allergy, as demonstrated by increased plasma levels of peanut-specific IgE and the manifestation of acute systemic anaphylaxis following intraperitoneal challenge with peanut extract. The development of peanut allergy was suppressed when mice had been given PNF sublingually before epicutaneous exposure. There were fewer T follicular helper cells in the skin-draining lymph nodes of mice that received sublingual PNF than in the mice that received PBS. Suppression of IgE production was observed with sublingual PNF at 1/10 of the intragastric PNF dose. CONCLUSION: Administration of peanut allergens only to the oral cavity effectively prevents the development of peanut allergy. The capacity of the oral mucosa to promote immunologic tolerance needs to be evaluated further to prevent food allergy.

Growth modulatory effects of fenretinide encompass keratinocyte terminal differentiation: a favorable outcome for oral squamous cell carcinoma chemoprevention.

Oral squamous cell carcinoma (OSCC) is worldwide health problem associated with high morbidity and mortality. From both the patient and socioeconomic perspectives, prevention of progression of premalignant oral intraepithelial neoplasia (OIN) to OSCC is clearly the preferable outcome. Optimal OSCC chemopreventives possess a variety of attributes including high tolerability, bioavailability, efficacy and preservation of an intact surface epithelium. Terminal differentiation, which directs oral keratinocytes leave the proliferative pool to form protective cornified envelopes, preserves the protective epithelial barrier while concurrently eliminating growth-aberrant keratinocytes. This study employed human premalignant oral keratinocytes and an OSCC cell line to evaluate the differentiation-inducing capacity of the synthetic retinoid, fenretinide (4HPR). Full-thickness oral mucosal explants were evaluated for proof of concept differentiation studies. Results of this study characterize the ability of 4HPR to fulfill all requisite components for keratinocyte differentiation, i.e. nuclear import via binding to cellular RA binding protein-II (molecular modeling), binding to and subsequent activation of retinoic acid nuclear receptors (receptor activation assays), increased expression and translation of genes associated with keratinocyte differentiation [Reverse transcription polymerase chain reaction (RT-PCR), immunoblotting] upregulation of a transglutaminase enzyme essential for cornified envelope formation (transglutaminase 3, functional assay) and augmentation of terminal differentiation in human oral epithelial explants (image-analyses quantified corneocyte desquamation). These data build upon the chemoprevention repertoire of 4HPR that includes function as a small molecule kinase inhibitor and inhibition of essential mechanisms necessary for basement membrane invasion. An upcoming clinical trial, which will assess whether a 4HPR-releasing mucoadhesive patch induces histologic, clinical and molecular regression in OIN lesions, will provide essential clinical insights.

Langerhans cells in the skin and oral mucosa: Brothers in arms?

The skin and the oral mucosa represent interfaces to the environment that are constantly exposed to pathogens and harmless foreign antigens such as commensal bacteria. Both barrier organs share the presence of Langerhans cells (LC), distinctive members of the heterogeneous family of antigen-presenting dendritic cells (DC) that have the unique ability to promote tolerogenic as well as inflammatory immune responses. While skin LC have been extensively studied in the past decades, less is known about the function of oral mucosal LC. Despite similar transcriptomic signatures, skin and oral mucosal LC differ greatly in their ontogeny and development. In this review article, we will summarize the current knowledge on LC subsets in the skin compared to the oral mucosa. We will discuss the similarities and differences in their development, homeostasis, and function in the two barrier tissues, including their interaction with the local microbiota. In addition, this review will update recent advances on the role of LC in inflammatory skin and oral mucosal diseases.

Comparative evaluation of autologous tissue-engineered ocular and oral mucosal tissue grafts- a prospective randomized controlled trial.

BACKGROUND: Bilateral ocular surface disease resulting from Stevens Johnson Syndrome (SJS) and chemical injuries are visually debilitating and difficult to treat. Ocular surface reconstruction by various means has been reported with variable results. This study addresses an unmet need for a prospective clinical trial comparing the outcomes of transplanting autologous oral and conjunctival epithelial cell constructs on human amniotic membrane by ex vivo tissue engineering. METHODS: A prospective, randomized controlled clinical trial was prospectively applied for registration, with the clinical trial registry of India (CTRI), with the approval of the Institute Ethics Committee number IEC/NP-99/11.04.2014 and CTRI No. REF/2018/10/021791, the study also registered with the WHO-recognized trial registry, International Standard Randomised Controlled Trial Number (ISRCTN) registration reference number 45780. The study was conducted to compare clinical outcomes of two different tissue-engineered cell grafts, Cultivated Oral Mucosal Epithelial Transplantation (COMET) and Conjunctival Cultivated Epithelial Transplantation (CCET) for ocular surface reconstruction in patients with bilateral ocular surface disease due to Stevens-Johnson Syndrome or chemical injuries. Fifty patients were enrolled and randomized to either the COMET or CCET group. A uniform pre-op and post-op protocol using standard medications was followed for all patients Parameters assessed at baseline, day 1, 1 week, 2 weeks, 1 month, 2 months, 3 months and 6 months postoperatively included patient comfort, best corrected visual acuity (BCVA), ocular surface status and corneal clarity. The efficacy was measured in terms of improvement of vision, reduction in vascularization, symblepharon and corneal clarity. RESULTS: In the study, 50 patients (50 eyes; mean ages of 29 ± 15.86 years and 26.36 ± 10.85 years, respectively; range, 12-65 years) were enrolled, with 25 patients each in the COMET and CCET groups. Out of them, 36% were female and 64% were male; the causes were Steven Johnson syndrome (48), and chemical injury (2). Mean pre-operative BCVA was log MAR 1.73 ± 0.57 for COMET and 1.99 ± 0.33 for the CCET group. Pre-operatively all 50 enrolled patients had opaque corneas pre-operatively, symblepharon that extended to the cornea categorised as grade 3 and corneal vascularization that went beyond the pupil's boundary into the central zone encluaching on the visual axis. The minimal follow-up time was six months. Following surgery postoperatively, the BCVA considerably improved in the COMET group by 1.51 ± 0.58 compared to the CCET group by 1.91 ± 0.33 at 3 months. BCVA at 6 months was 1.73 ± 0.56 in the COMET group and 1.99 ± 0.31 in the CCET group, which is not statistically significant and comparable to the BCVA before surgery. The corneal clarity was significantly improved in COMET group 25 eye (100%) at 2 month, 3month and 19 eye (76%), 6eye (24%) at 6 months when compared to CCET group 15 eye improved (60%), 9 eyes (36%) not improved and one eye with opaque cornea (4%) at 2 months. 22 eye (88%) had not improved, 2 eye (8%) opaque cornea and 1 eye (4%) improved at 3 months. At 6 months 21 eye (84%) were not improved, 4 eye (16%) eye became opaqued at 6 months. Compared to preoperative conditions, both groups had improved corneal clarity significantly (p > 0.005). Of the 50 patients with grade 3 symblepharon extended to the cornea, were completely resolved 19 (76%) in COMET group when compared to CCET group 22 eye (88%) not improved. Similarly, 19 eye (76%) had a improvement in corneal vascularization when compared to the CCET group not improved 25 eye (100%) at 6months. No adverse event was observed in any of either group during the follow up periods. CONCLUSION: Both cell types are effective to restore the ocular surface integrity in bilateral ocular surface disease. Whereas COMET is safe and efficacious in terms of improvement of clinical parameters including, BCVA, corneal clarity, reduction in vascularization and preventing the recurrence of symblepharon postoperatively 3months and 6 months. In addition, the CCET group maintained the stability of the ocular surface and had improvement in corneal clarity and a decrease in vascularization at 3 months compared to their pre-operative characteristics.

Activating the healing process: three-dimensional culture of stem cells in Matrigel for tissue repair.

BACKGROUND: To establish a strategy for stem cell-related tissue regeneration therapy, human gingival mesenchymal stem cells (hGMSCs) were loaded with three-dimensional (3D) bioengineered Matrigel matrix scaffolds in high-cell density microtissues to promote local tissue restoration. METHODS: The biological performance and stemness of hGMSCs under 3D culture conditions were investigated by viability and multidirectional differentiation analyses. A Sprague‒Dawley (SD) rat full-thickness buccal mucosa wound model was established, and hGMSCs/Matrigel were injected into the submucosa of the wound. Autologous stem cell proliferation and wound repair in local tissue were assessed by histomorphometry and immunohistochemical staining. RESULTS: Three-dimensional suspension culture can provide a more natural environment for extensions and contacts between hGMSCs, and the viability and adipogenic differentiation capacity of hGMSCs were significantly enhanced. An animal study showed that hGMSCs/Matrigel significantly accelerated soft tissue repair by promoting autologous stem cell proliferation and enhancing the generation of collagen fibers in local tissue. CONCLUSION: Three-dimensional cell culture with hydrogel scaffolds, such as Matrigel, can effectively improve the biological function and maintain the stemness of stem cells. The therapeutic efficacy of hGMSCs/Matrigel was confirmed, as these cells could effectively stimulate soft tissue repair to promote the healing process by activating the host microenvironment and autologous stem cells.

In vitro Models for Predicting Bioadhesion Fracture Strength to Ex Vivo Animal Buccal Tissue.

Commitment to the 3Rs principle (Replacement, Reduction, and Refinement) led to the development of a cell-based system to measure buccal bioadhesion in vitro and replace the use of porcine buccal and esophageal tissues (PBT and PET, respectively). Additionally, the aim is to bridge the gap in knowledge regarding the bioadhesion properties of PBT and PET. The in vitro models are based on the human buccal epithelial cell line-TR146 without ("Model I") or with ("Model II") 5% (w/v) mucous layer. The in vitro setup also provides a method to evaluate the bioadhesion between two soft materials. Standard bioadhesive hydrogels (alginate, chitosan, and gelatin) are used to test and compare the results from the in vitro models to the ex vivo tissues. The ex vivo and in vitro models show increased bioadhesion as the applied force and contact time increases. Furthermore, Model I exhibits bioadhesion values-of alginate, chitosan, and gelatin-comparable to those obtained with PBT. It is also found that contact time and applied force similarly affect PBT and PET bioadhesion, while PET exhibits greater values. In conclusion, Model I can replace PBT for measuring bioadhesion and be incorporated into the experimental design of bioadhesive DDS, thus minimizing animal tissue usage.

Thalidomide attenuates radiation-induced apoptosis and pro-inflammatory cytokine secretion in oral epithelial cells by promoting LZTS3 expression.

Radiation-induced oral mucositis (RIOM) is a prevalent oral complication that occurs in individuals undergoing radiotherapy or radiation treatment for head and neck tumors. The presence of oral mucosal rupture and ulcerative lesions, which are the defining features of this condition, can significantly affect the quality of life of patients. Additionally, it can interfere with tumor therapy and contribute to an unfavorable prognosis. Current evidence suggests that cellular inflammation and programmed cell death are important factors in disease development. Moreover, thalidomide (THD) has been revealed to reduce the incidence and severity of RIOM in patients undergoing chemoradiotherapy for nasopharyngeal carcinoma. However, the mechanism through which THD improves RIOM remains unknown. This study aimed to investigate the role of LZTS3 in RIOM by analyzing various sequencing datasets and conducting knockdown and overexpression experiments. We used small interfering RNA transfection and LZTS3 overexpression, followed by validation through polymerase chain reaction, western blotting, flow cytometry, and enzyme-linked immunosorbent assay. In this study, we identified LZTS3 as a potential target for THD regulation in RIOM. Through a series of experiments, we confirmed that LZTS3 has the ability to inhibit the inflammatory response and apoptosis of cells. In addition, we also found that THD can regulate the expression of LZTS3 by upregulating, thereby affecting inflammatory response and apoptosis. We repeated these results in a live animal model. In summary, THD has the potential to reduce the occurrence of oral mucositis in patients by upregulating LZTS3 levels. These findings provide a promising avenue for future drug research and development to treat RIOM.

Candida albicans commensalism in the oral mucosa is favoured by limited virulence and metabolic adaptation.

As part of the human microbiota, the fungus Candida albicans colonizes the oral cavity and other mucosal surfaces of the human body. Commensalism is tightly controlled by complex interactions of the fungus and the host to preclude fungal elimination but also fungal overgrowth and invasion, which can result in disease. As such, defects in antifungal T cell immunity render individuals susceptible to oral thrush due to interrupted immunosurveillance of the oral mucosa. The factors that promote commensalism and ensure persistence of C. albicans in a fully immunocompetent host remain less clear. Using an experimental model of C. albicans oral colonization in mice we explored fungal determinants of commensalism in the oral cavity. Transcript profiling of the oral isolate 101 in the murine tongue tissue revealed a characteristic metabolic profile tailored to the nutrient poor conditions in the stratum corneum of the epithelium where the fungus resides. Metabolic adaptation of isolate 101 was also reflected in enhanced nutrient acquisition when grown on oral mucosa substrates. Persistent colonization of the oral mucosa by C. albicans also correlated inversely with the capacity of the fungus to induce epithelial cell damage and to elicit an inflammatory response. Here we show that these immune evasive properties of isolate 101 are explained by a strong attenuation of a number of virulence genes, including those linked to filamentation. De-repression of the hyphal program by deletion or conditional repression of NRG1 abolished the commensal behaviour of isolate 101, thereby establishing a central role of this factor in the commensal lifestyle of C. albicans in the oral niche of the host.

Fibrotic Matrix Induces Mesenchymal Transformation of Epithelial Cells in Oral Submucous Fibrosis.

Oral submucous fibrosis (OSF) is a potentially malignant disorder of the oral mucosa; however, whether and how the fibrotic matrix of OSF is involved in the malignant transformation of epithelial cells remains unknown. Herein, oral mucosa tissue from patients with OSF, OSF rat models, and their controls were used to observe the extracellular matrix changes and epithelial-mesenchymal transformation (EMT) in fibrotic lesions. Compared with controls, oral mucous tissues from patients with OSF showed an increased number of myofibroblasts, a decreased number of blood vessels, and increased type I and type III collagen levels. In addition, the oral mucous tissues from humans and OSF rats showed increased stiffness, accompanied by increased EMT activities of epithelial cells. The EMT activities of stiff construct-cultured epithelial cells were increased significantly by exogenous piezo-type mechanosensitive ion channel component 1 (Piezo1) activation, and decreased by yes-associated protein (YAP) inhibition. During ex vivo implantation, oral mucosal epithelial cells of the stiff group showed increased EMT activities and increased levels of Piezo1 and YAP compared with those in the sham and soft groups. These results indicate that increased stiffness of the fibrotic matrix in OSF led to increased proliferation and EMT of mucosal epithelial cells, in which the Piezo1-YAP signal transduction is important.

Affirming Long-Term Outcomes After Contemporary Urethroplasty: The Adverse Impact of Increasing Stricture Length, Lichen Sclerosus, Radiation, and Infectious Strictures.

PURPOSE: There is a paucity of reported long-term outcomes after contemporary urethroplasty. Our objective is to determine the long-term success of modern urethroplasty and identify factors associated with stricture recurrence in this context. MATERIALS AND METHODS: Patients undergoing urethroplasty from July 2003 to May 2013 with at least 100 months of follow-up were identified. Long-term outcomes including stricture recurrence and patient satisfaction were evaluated by review of regional/provincial electronic records and telephone interview. Urethroplasty failure was defined as a recurrent stricture (<16F) confirmed on cystoscopy. Cox regression was used to evaluate variables associated with long-term stricture recurrence. RESULTS: A total of 733 patients were identified with ≥ 100 months follow-up. Median patient age was 45 years, stricture length was 4.7 cm, and 85.8% failed prior endoscopic treatment. At a median follow-up of 12.3 years, 89 recurrences were observed. Cumulative incidence of stricture recurrence was 6%, 10%, and 12% after 1, 5, and 10 years, respectively. From a patient-reported perspective, 89% of patients reported being satisfied with the outcome of surgery. On multivariable analyses, increasing stricture length (HR 1.1, 95% CI 1.05-1.15; P < .001) and stricture etiology (P < .001), in particular lichen sclerosus (HR 4.46, 95% CI 2.25-9.53), radiation (HR 4.25, 95% CI 1.65-10.9), and infectious strictures (HR 5.27, 95% CI 2.03-13.7), were independently associated with stricture recurrence. CONCLUSIONS: This study affirms the widely held belief that modern urethroplasty provides high long-term patency and patient-reported satisfaction. Patients with longer strictures as well as those with lichen sclerosus, radiation, and infectious etiologies have a higher hazard of stricture recurrence in the long term.

Multi-Institutional Outcomes of Dorsal Onlay Buccal Mucosal Graft Urethroplasty in Patients With Postprostatectomy, Postradiation Anastomotic Stenosis.

PURPOSE: The treatment of urethral stenosis after a combination of prostatectomy and radiation therapy for prostate cancer is understudied. We evaluate the clinical and patient-related outcomes after dorsal onlay buccal mucosal graft urethroplasty (D-BMGU) in men who underwent prostatectomy and radiation therapy. MATERIALS AND METHODS: A multi-institutional, retrospective review of men with vesicourethral anastomotic stenosis or bulbomembranous urethral stricture disease after radical prostatectomy and radiation therapy from 8 institutions between 2013 to 2021 was performed. The primary outcomes were stenosis recurrence and development of de novo stress urinary incontinence. Secondary outcomes were surgical complications, changes in voiding, and patient-reported satisfaction. RESULTS: Forty-five men were treated with D-BMGU for stenosis following prostatectomy and radiation. There was a total of 7 recurrences. Median follow-up in patients without recurrence was 21 months (IQR 12-24). There were no incidents of de novo incontinence, 28 patients were incontinent pre- and postoperatively, and of the 6 patients managed with suprapubic catheter preoperatively, 4 were continent after repair. Following repair, men had significant improvement in postvoid residual, uroflow, International Prostate Symptom Score, and International Prostate Symptom Score quality-of-life domain. Overall satisfaction was +2 or better in 86.6% of men on the Global Response Assessment. CONCLUSIONS: D-BMGU is a safe, feasible, and effective technique in patients with urethral stenosis after a combination of prostatectomy and radiation therapy. Although our findings suggest this technique may result in lower rates of de novo urinary incontinence compared to conventional urethral transection and excision techniques, head-to-head comparisons are needed.

Potential role of salivary lactic acid bacteria in pathogenesis of oral lichen planus.

BACKGROUND: Emerging evidence emphasized the role of oral microbiome in oral lichen planus (OLP). To date, no dominant pathogenic bacteria have been identified consistently. It is noteworthy that a decreased abundance of Streptococcus, a member of lactic acid bacteria (LAB) in OLP patients has been commonly reported, indicating its possible effect on OLP. This study aims to investigate the composition of LAB genera in OLP patients by high-throughput sequencing, and to explore the possible relationship between them. METHODS: We collected saliva samples from patients with OLP (n = 21) and healthy controls (n = 22) and performed 16 S rRNA gene high-throughput sequencing. In addition, the abundance of LAB genera was comprehensively analyzed and compared between OLP and HC group. To verify the expression of Lactococcus lactis, real time PCR was conducted in buccal mucosa swab from another 14 patients with OLP and 10 HC. Furthermore, the correlation was conducted between clinical severity of OLP and LAB. RESULTS: OLP and HC groups showed similar community richness and diversity. The members of LAB, Lactococcus and Lactococcus lactis significantly decreased in saliva of OLP cases and negatively associated with OLP severity. In addition, Lactococcus and Lactococcus lactis showed negative relationship with Fusobacterium and Aggregatibacter, which were considered as potential pathogens of OLP. Similarly, compared with healthy controls, the amount of Lactococcus lactis in mucosa lesion of OLP patients was significantly decreased. CONCLUSIONS: A lower amount of Lactococcus at genus level, Lactococcus lactis at species level was observed in OLP cases and associated with disease severity. Further studies to verify the relationship between LAB and OLP, as well as to explore the precise mechanism is needed.

Primary Tumour Detection in Carcinoma of Unknown Primary with Transoral Robotic Surgery (TORS) Tongue Base Mucosectomy: A Meta-analysis.

BACKGROUND: Head and neck carcinoma of unknown primary (CUP) represents a challenging diagnostic process when standard work-up fails to identify the primary tumour site. The aim of this systematic review and meta-analysis was to evaluate the diagnostic utility and complication profile of transoral robotic surgery (TORS) tongue base mucosectomy (TBM) in the management of CUP. PATIENTS AND METHODS: An electronic database search was performed in the EMBASE, MEDLINE, PubMed and Cochrane databases. A meta-analysis of proportions was performed to obtain an estimate of the overall proportion for the detection and complication rates. RESULTS: Nine studies representing 235 patients with CUP who had TORS TBM were included in the final analysis. The overall pooled tumour detection rate was 66.2% [95% confidence interval (CI) 56.1-75.8]. The incidence of tumour detection in human papilloma virus (HPV)-positive cases (81.5%, 95% CI 60.8-96.4) was significantly higher than HPV-negative cases (2.3%, 95% CI 0.00-45.7). Weighted overall complication rate was 11.4% (95% CI 7.2-16.2). The majority were grade I or II (80%) according to the Clavien-Dindo classification. CONCLUSIONS: This meta-analysis suggests TORS to be safe and effective in localising the primary tumour site in patients with CUP. While the current data supports the use of TORS in patients who are HPV positive, larger numbers of HPV-negative cases are required to determine the true diagnostic effect with TORS before any valid conclusions can be inferred in this particular subgroup. Further research should focus on high quality prospective trials with stringent methodological work-up to minimise heterogeneity and allow for more accurate statistical analysis.