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Objetivo: Fornecer um guia no formato de checklist para auxiliar pesquisadores na condução de revisões integrativas em Odontologia. Métodos: O guia para revisões integrativas em Odontologia foi construído a partir do Preferred Reporting Items for Systematic Reviews and Meta-Analyses (The PRISMA Statement). Resultados: Para o delineamento de revisões integrativas em Odontologia é preciso percorrer etapas distintas: 1. Identificação do tema (elaboração da pergunta de pesquisa); 2. Estabelecimento dos critérios de elegibilidade de estudos; 3. Busca sistematizada em diversas fontes de informação; 4. Coleta de dados; 5. Análise dos dados; 6. Discussão; 7. Apresentação da revisão/síntese do conhecimento. Os erros mais comuns ao realizar uma revisão integrativa estão relacionados à descrição incompleta ou não realização de etapas importantes, tais como: 1. Processo de seleção das evidências; 2. Estratégia de busca reprodutível; 3. Detalhes relacionados à busca, seleção e inclusão de estudos; 4. Aplicação dos critérios de elegibilidade; 5. Processo de extração dos dados (definição clara dos dados a serem extraídos, número de revisores envolvidos); 6. Apresentação do processo de seleção de estudos no formato de fluxograma; 7. Avaliação da qualidade dos estudos; 8. Síntese dos resultados. Conclusão: O guia para revisões integrativas em Odontologia apresenta utilidade na redução de equívocos metodológicos frequentemente observados nesse desenho de estudo, bem como estimula a condução de trabalhos com delineamentos robustos.

The microenvironment of oral cancer is highly dynamic and has been proved to affect tumor progression. Pericytes are blood vessels surrounding cells that have recently gained attention for their roles in vascular and cancer biology. The objective of the present study was to survey the scientific literature for conclusive evidence about whether pericytes are part of blood vessels in oral squamous cell carcinoma (OSCC) and their roles in the tumor microenvironment and clinical outcomes. A systematic electronic search was undertaken in Medline Ovid, PubMed, Web of Science, and Scopus. Eligibility criteria were: publications adopting in vivo models of OSCC that included pericyte detection and assessment by pericyte markers (e.g., α-smooth muscle actin, neuron-glial antigen 2 and platelet-derived growth factor receptor-β). The search yielded seven eligible studies (from 2008 to 2018). The markers most commonly used for pericyte detection were α-smooth muscle actin and neuron-glial antigen 2. The studies reviewed showed the presence of immature vessels exhibiting a reduction of pericyte coverage in OSCC and indicated that anti-cancer therapies could contribute to vessel normalization and pericyte regain. The pericyte population is significantly affected during OSCC development and cancer therapy. While these findings might suggest a role for pericytes in OSCC progression, the limited data available do not allow us to conclude whether they modify the tumor microenvironment and clinical outcome. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12105-020-01188-2) contains supplementary material, which is available to authorized users.

Background Chemokines and chemokine receptors are critical in oral tumourigenesis. The atypical chemokine receptor ACKR2 is a scavenger of CC chemokines controlling the availability of these molecules at tumour sites, but the role of ACKR2 in the context of oral carcinogenesis is unexplored. Methods In this study, wild-type (WT) and ACKR2 deficient mice (ACKR2−/−) were treated with chemical carcinogen 4-nitroquinoline-1-oxide (4NQO) for induction of oral carcinogenesis. Tongues were collected for macro and microscopic analysis and to evaluate the expression of ACKRs, CC chemokines and its receptors, inflammatory cytokines, angiogenic factors, adhesion molecules and extracellular matrix components. Results An increased expression of ACKR2 in squamous cell carcinoma (SCC) lesions of 4NQO-treated WT mice was observed. No significant differences were seen in the ACKR1, ACKR3 and ACKR4 mRNA expression comparing SCC lesions from WT and ACKR2−/− treated mice. Significantly higher expression of CCL2, IL-6 and IL-17 was detected in ACKR2−/− treated mice. In contrast, the expression of other CC-chemokines, and receptors, angiogenic factors, adhesion molecules and extracellular matrix components were similarly increased in SCC lesions of both groups. Clinical and histopathological analysis revealed no differences in inflammatory cell recruitment and in the SCC incidence comparing WT and ACKR2−/− treated mice. Conclusion The results suggest that ACKR2 expression regulates inflammation in tumour-microenvironment but the absence of ACKR2 does not impact chemically-induced oral carcinogenesis.

Rheumatoid arthritis (RA) is an autoimmune disorder associated with increased periodontal destruction. It is thought that RA increases the risk of periodontal disease; it is not known how it influences the oral microbiota. Our aim was to analyze the impact of RA on subgingival microbiota and its association with periodontal inflammation and RA activity. Forty-two patients with RA were compared to 47 control subjects without RA. Patients were screened for probing depth, clinical attachment level, bleeding on probing and classified as with or without periodontitis. Subgingival plaque was examined by Illumina MiSeq Sequencing of 16S rRNA gene V4 region and inflammatory cytokines were measured in saliva. RA was associated to severe periodontal disease. In addition, the severity of RA, reflected by the number of tender and swollen joints, was significantly correlated with the presence of pathogenic oral bacteria (i.e. Fusobacterium nucleatum and Treponema socransky). Non-periodontitis RA patients compared to healthy controls had increased microbial diversity and bacterial load, higher levels of pathogenic species (Prevotella, Selenomonas, Anaeroglobus geminatus, Parvimonas micra, Aggregatibacter actinomycetemcomitans) and reduction of health-related species (Streptococcus, Rothia aeria, Kingela oralis). Genes involved with bacterial virulence (i.e. lipopolysaccharide biosynthesis, peptidases) were more prevalent in the subgingival metagenome of subjects with RA. In addition, the degree of oral inflammation reflected by IL-2, IL-6, TNF-α, IFN-γ salivary levels was increased in non-periodontitis RA patients in comparison with controls. Our findings support the hypothesis that RA triggers dysbiosis of subgingival microbiota, which may contribute to worsening periodontal status.Author SummaryRheumatoid arthritis (RA) is an autoimmune disease characterized by joints inflammation, swelling, pain and stiffness. Exactly what starts this disease is still unclear. Some recent studies have suggested mucosal surfaces in the body, like those in the gums, could affect the disease process. It has been observed that people with RA have higher risk of periodontitis (a bacterial inflammatory disease of the gums), compared with the general population, and this may be the start of the autoimmune process. Also, periodontitis increases the severity of RA while interventions by treating periodontitis can improve the symptoms of RA. One of the possible mechanisms that link the higher prevalence of periodontitis in RA patients is the dysbiosis of the oral microbiota triggered by the chronic inflammation in RA. Increased levels of molecules of inflammation may affect the oral environment and change the type of bacteria that live there. Here, we examined RA patients and healthy subjects, screening their oral health and inflammatory markers. We collected their saliva and the dental plaque from the space between the teeth and the gum. We found that RA patients exhibited severe periodontitis, increased levels of inflammatory mediators on their saliva and distinct bacterial communities, with higher proportions of bacteria species linked to periodontal disease, even in patients without periodontitis. We also found that the presence of these bacteria species was linked to worse RA conditions. Our study provides new insights to understand the bi-directional mechanisms linking periodontal disease to the development of RA, showing that we need to pay attention to the oral cavity in patients with RA and refer people for dental evaluation. This practice might have a positive impact in the course of RA.

Bisphenol A (BPA) is an endocrine disrupting chemical able to promote hormone-responsive tumors. The major route of BPA contamination being oral, the aim of the present study was to investigate BPA effects on oral cells. Here, we evaluated the impact of sub-chronic in vivo exposure to BPA and its in vitro effects on neoplastic and non-neoplastic oral cells. We evaluated the oral mucosa of mice chronically exposed to BPA (200 mg/L). The response of keratinocytes (NOK–SI) and Head and Neck (HN) Squamous Cell Carcinoma (SCC), HN12 and HN13 cell lines to BPA was examined. In vivo, BPA accumulated in oral tissues and caused an increase in epithelial proliferative activity. BPA disrupted the function of keratinocytes by altering pro-survival and proliferative pathways and the secretion of cytokines and growth factors. In tumor cells, BPA induced proliferative, invasive, pro-angiogenic, and epigenetic paths. Our data highlight the harmful effects of BPA on oral mucosa and, tumorigenic and non-tumorigenic cells. Additionally, BPA may be a modifier of oral cancer cell behavior by prompting a functional shift to a more aggressive phenotype.

The chemokine CCL3 is a chemotactic cytokine crucial for inflammatory cell recruitment in homeostatic and pathological conditions. CCL3 might stimulate cancer progression by promoting leukocyte accumulation, angiogenesis and tumour growth. The expression of CCL3 and its receptors CCR1 and CCR5 was demonstrated in oral squamous cell carcinoma (OSCC), but their role was not defined. Here, the functions of CCL3 were assessed using a model of chemically induced tongue carcinogenesis with 4-nitroquinoline-1-oxide (4NQO). Lineages of OSCC were used to analyse the effects of CCL3 in vitro. The 4NQO-induced lesions exhibited increased expression of CCL3, CCR1 and CCR5. CCL3-/- and CCR5-/- mice presented reduced incidence of tongue tumours compared to wild-type (WT) and CCR1-/- mice. Consistently, attenuated cytomorphological atypia and reduced cell proliferation were observed in lesions of CCL3-/- and CCR5-/- mice. OSCC from CCL3-/- mice exhibited lower infiltration of eosinophils and reduced expression of Egf, Fgf1, Tgf-β1, Vegfa, Vegfb, Itga-4, Vtn, Mmp-1a, Mmp-2 and Mmp-9 than WT mice. In vitro, CCL3 induced invasion and production of CCL5, IL-6, MMP -2, -8, -9. Blockage of CCL3 in vitro using α-CCL3 or Evasin-1 (a CCL3-binding protein) impaired tumour cell invasion. In conclusion, CCL3/CCR5 axis has pro-tumourigenic effects in oral carcinogenesis. The induction of inflammatory and angiogenic pathways and eosinophils recruitment appear to be the underlying mechanism explaining these effects. These data reveal potential protective effects of CCL3 blockade in oral cancer.

Introduction Bone remodeling is a tightly regulated process influenced by chemokines. ACKR2 is a decoy receptor for CC chemokines functioning as regulator of inflammatory response. In this study we investigated whether the absence of ACKR2 would affect bone phenotype and remodeling induced by mechanical loading. Methods An orthodontic appliance was placed between incisors and first molar of ACKR2 deficient (ACKR2 −/− ) and C57BL6/J (wild-type/WT) mice. Microtomography, histology and qPCR were performed to evaluate bone parameters, orthodontic tooth movement (OTM), bone cells counts and the expression of ACKR2, bone remodeling markers, CC chemokines and chemokines receptors. Bone marrow cells (BMC) from WT and ACKR2 −/− mice were differentiated in osteoclasts and osteoblasts for analysis of activity and expression of specific markers. Results Mechanical stimulus induced ACKR2 production in periodontium. The expression of ACKR2 in vitro was mostly detected in mature osteoclasts and early-differentiated osteoblasts. Although ACKR2 −/− mice exhibited regular phenotype in maxillary bone, the amount of OTM, osteoclasts counts and the expression of pro-resorptive markers were increased in this group. In contrast, the number of osteoblasts and related markers were decreased. OTM resulted in augmented expression of CC chemokines and receptors CCR5 and CCR1 in periodontium, which was higher in ACKR2 −/− than WT mice. In vitro experiments demonstrated an augmented formation of osteoclasts and diminished differentiation of osteoblasts in ACKR2 −/− mice. Conclusions These data suggests that ACKR2 functions as a regulator of mechanically-induced bone remodeling by affecting the differentiation and activity of bone cells and the availability of CC chemokines at periodontal microenvironment. Therapeutic strategies based on increase of ACKR2 might be useful to hinder bone loss in inflammatory conditions.

A quimiocina CCL3 possui uma diversidade de papéis que podem contribuir para o pior prognóstico do Carcinoma de células escamosas de boca (CCEB); Métodos: Camundongos machos C57BL/6 (WT) e deficientes de CCL3 (CCL3-/-) foram tratados com o 4NQO durante 20 ou 28 semanas. As línguas foram coletadas para análise macroscópica, histopatológica e imunohistoquímica. Os níveis de citocinas também foram avaliados por ELISA. Resultados: Nossos resultados mostraram uma incidência significativamente maior de CCEB nas línguas dos animais WT em comparação com os animais CCL3-/-. Consistente com estes achados, a análise microscópica demonstrou uma proeminente displasia epitelial no grupo WT. A imunoexpressão de PCNA e Ki67 revelou um significativo aumento no índice de proliferação celular nos animais WT, comparados ao grupo CCL3-/-. A concentração de CCL3, TNF-, CCL5 e CCL11 foi significativamente aumentada após o tratamento com 4NQO, entretanto, os animais CCL3-/- mostraram níveis mais baixos de TNF- quando comparados ao grupo WT. Conclusão: Estes dados sugerem que a deleção de CCL3 tem um efeito protetor na carcinogênese oral, o qual pode estar associado com mudanças locais na produção de TNF-. The chemokine CCL3 displays a diversity of roles that may contribute to worse prognosis in oral carcinogenesis. The aim of this study was to evaluate the role of CCL3 in 4-nitroquinoline-1-oxide (4NQO)-induced oral carcinogenesis. C57BL/6 (wild type - WT) and CCL3 deficient (CCL3-/-) male mice were treated with 4NQO in drinking water at concentration of 50 ìg/ml during 20 or 28 weeks Their tongues were collected for macroscopic, histopathological and immunohistochemical analysis. Also, the cytokine levels in tongue lesions were evaluated by ELISA. Our results showed a significantly higher incidence of tumors in tongue of WT- in comparison with CCL3-/-- treated mice. Consistently, microscopic analysis demonstrated a pronounced cytological atypia in the WT-treated group. The immunoexpression of PCNA and Ki67 revealed a significant increase of the proliferative index in WT compared with CCL3-/--treated group. The concentration of CCL3, TNF-á, CCL5 and CCL11 was significantly enhanced after 4NQO treatment, but CCL3-/--treated mice showed lower TNF-á level when compared with WT. In conclusion, these data suggest a protective effect of CCL3deletion in oral tongue carcinogenesis which may be associated with local changes in TNF-á production.