Immunoexpression of ALDH1A1, FGFR2, CD44 and Caspase-3 in Oral Squamous Cell Carcinoma and Leukoplakia: A pilot study

Current research highlighted the importance to recognize feasible biomarkers for early diagnoses and treatment in oral cancer. Our study analyzed the expression and spatial distribution of ALDH1A1, FGFR2, caspase-3, and CD44 in Oral Squamous Cell Carcinoma (OSCC) and leukoplakia with and without oral mucosal dysplasia. Paraffin-embedded samples of OSCC (n=5), leukoplakia with (n=5) and without (n=5) dysplasia obtained by incisional biopsies were processed using conventional histochemical techniques. Immunohistochemistry was performed using antibodies against ALDH1A1, FGFR2, caspase-3, and CD44. Images of the immunohistochemically stained tissue sections were analyzed according to the intensity of the immunostaining of each marker and classified in Scores. The Kruskal- Wallis test was performed (p≤0.05). Our results demonstrated a statically difference in the expression of all immunomarkers between OSCC and leukoplakia without dysplasia, being more significant in FGFR2 and ALDH1A1. Within the limitations of this study, our data showed that all biomarkers were overexpressed in OSCC and leukoplakia with oral mucosa dysplasia, suggesting that the presence of dysplasia is a significant clinic-pathologic predictor for malignant transformation.

La actual evidencia científica enfatiza la importancia de reconocer biomarcadores viables para el diagnóstico y tratamiento temprano del cáncer oral. Nuestro estudio piloto analizó la expresión y distribución espacial de ALDH1A1, FGFR2, caspasa-3 y CD44 en carcinoma oral de células escamosas (COCE) y en leucoplasia con o sin displasia de la mucosa oral. Las muestras incluidas en parafina de COCE (n=5), con (n=5) y sin (n=5) displasia fueron obtenidas mediante biopsias incisionales, las cuales se procesaron utilizando técnicas histoquímicas convencionales. El análisis inmunohistoquímico se realizó utilizando anticuerpos contra ALDH1A1, FGFR2, caspasa-3 y CD44. Las imágenes de las secciones de cada muestra fueron analizadas según la intensidad de inmunoexpresión de cada marcador y se clasificaron en diferentes escalas (scores). Se realizó la prueba de Kruskal-Wallis (valores de p<0,05). Nuestros resultados demostraron una diferencia estadística en la expresión de todos los inmunomarcadores entre COCE y las muestras con leucoplasia sin displasia, siendo más significativa en FGFR2 y ALDH1A1. Considerando las limitaciones de este estudio, los datos sugieren que la presencia de displasia en la mucosa oral es un importante predictor clínico-patológico de transformación maligna.

In vivo host interactions with mineral trioxide aggregate and calcium hydroxide: inflammatory molecular signaling assessment.

INTRODUCTION: Mineral trioxide aggregate (MTA) and calcium hydroxide [Ca(OH)(2)] are promising biomaterials for stimulating dentinogenesis and cementogenesis. This research was undertaken to understand how MTA and CA(OH)(2) participate in the inflammatory, healing, and biomineralization processes. In this part of the study, we evaluated inflammatory signaling molecules promoted by in vivo host interaction with MTA and Ca(OH)(2). METHODS: Human dentin tubes were filled with ProRoot MTA (Dentsply Tulsa Dental, Tulsa, OK), Ca(OH)(2), or kept empty. After 12 hours and 1, 3, 7, 15, 30, and 60 days of implantation in subcutaneous tissues in the backs of mice, the tubes and surrounding tissues were retrieved for cytokine level quantification and histological and immunohistochemical analysis. RESULTS: MTA and Ca(OH)(2) induced proinflammatory cytokine up-regulation for up to 3 days. Moreover, interleukin-10 overexpression was noted on the tissue in contact with the biomaterials during the acute phase of the inflammatory reaction. Immunohistochemical analyses showed an increased expression of myeloperoxidase, nuclear factor kappa B (NF-κB), cyclooxygenase-2, inducible nitric oxide synthase enzymes, and vascular endothelial growth factor on day 1 for all groups. CONCLUSIONS: MTA and Ca(OH)(2) increased the activation of the NF-κB signaling system on day 1 for all groups. This finding can be associated with a proinflammatory and pro-wound healing environment, which was promoted earlier by MTA.

Primary teeth show less protecting factors against root resorption.

BACKGROUND: Physiological root resorption differentiates primary from permanent teeth. The understanding of what protects and regulates root resorption might help to develop therapies to its control. AIM: To verify the presence and distribution of ECRM and the expression of CK14, OPG, TRAP and COX-2 in the periodontal ligament (PDL) of human primary and permanent teeth. Design. Eight primary teeth undergoing physiological or pathological root resorption and 4 permanent teeth were immunohistochemically processed for CK14, TRAP, COX-2 and OPG expression. RESULTS: PDL from primary and permanent teeth showed similar morphological features; however, fewer ECRM clusters and higher immunoreactivity to CK14 were found in primary PDL. In permanent teeth, ECRM were distributed along the entire PDL tissue. Howship's lacunae were found only in primary teeth, associated with the presence of TRAP-positive cells and increase in COX-2 expression. OPG expression in primary PDL was detected in nonresorptive cervical areas and in lacunae showing reparative tissue. It was observed higher expression of OPG in all permanent teeth when compared to primary specimens. CONCLUSIONS: It may be concluded that PDL from primary teeth shows less ECRM clusters and lower expression of OPG. These features may be associated with lower protection against root resorption in primary teeth.

A phosphate-buffered saline intracanal dressing improves the biomineralization ability of mineral trioxide aggregate apical plugs.

INTRODUCTION: Recently, it was shown that the biomineralization process promoted by the interaction of mineral trioxide aggregate (MTA) with dentin in phosphate-buffered saline (PBS) positively influenced the push-out bond strength of the cement. This study investigated if the use of a PBS intracanal dressing promotes the biomineralization process of MTA apical plugs using an ex vivo apexification model. METHODS: White MTA was introduced into single-rooted teeth with standardized artificially created open apices to form 5-mm-thick apical plugs. The specimens were randomly divided into the following three groups of 10 samples each: group 1: the remaining canal space was filled with PBS as an intracanal dressing; group 2: the root segments were introduced in plastic vials containing floral foams with 20 mL of PBS; and group 3: the root segments were placed in the floral foams with 20 mL of PBS and a PBS intracanal dressing was used. After 2 months, the samples were processed for scanning electron microscopic observations. Data were analyzed by using the Kruskall-Wallis test. RESULTS: In group 1, the formation of an interfacial layer (IL) with intratubular mineralization (ITM) was more evident at the cervical third; however, no mineralization was revealed at the apical third. In group 2, there was no IL and/or ITM formation at the cervical third, but samples denoted IL and ITM formation at the apical third. Group 3 displayed the formation of IL and ITM at the different levels. CONCLUSION: It was concluded that the use of a PBS intracanal dressing promotes the biomineralization process at the inner side of MTA apical plugs.

Host-mineral trioxide aggregate inflammatory molecular signaling and biomineralization ability.

INTRODUCTION: The biological processes underlying the ability of mineral trioxide aggregate (MTA) to promote hard-tissue deposition and wound healing remain unclear. To further study these processes, specific signaling molecules related to the inflammatory response and the biomineralization process were analyzed to assess host-MTA interactions in vivo. METHODS: For cytokine level quantification and immunohistochemical analysis, human dentin tubes were filled with ProRoot MTA (Dentsply, Tulsa Dental, OK) or kept empty and were implanted in subcutaneous tissues in the backs of mice. Dentin tubes were retrieved and subsequently observed using a scanning electron microscope. RESULTS: MTA induced a time-dependent proinflammatory cytokine up-regulation up to 3 days. Immunohistochemical analyses showed an up-regulated expression of myeloperoxidase, nuclear factor-kappa B, activating protein-1, cyclooxygenase-2, inducible nitric oxide synthase, and vascular endothelial growth factor on day 1. Scanning electron microscopic examination revealed the presence of apatite-like clusters on collagen fibrils over the surface of tubes containing MTA. With the increase in time after implantation, a more extensive mineralization showing a compact layer of apatite was observed. CONCLUSION: MTA induced a proinflammatory and pro-wound healing environment. The biomineralization process occurred simultaneously at the biomaterial-dentin-tissue interface, with the acute inflammatory response. This promoted the integration of the biomaterial into the environment.

The biomineralization ability of mineral trioxide aggregate and Portland cement on dentin enhances the push-out strength.

INTRODUCTION: Recently, it was shown that the interaction of each of mineral trioxide aggregate (MTA) and Portland cement with dentin in phosphate-buffered saline (PBS) promotes a biomineralization process that leads to the formation of an interfacial layer with tag-like structures at the cement-dentin interface. This study analyzes the influence of the biomineralization process on the push-out strength of ProRoot MTA (Dentsply Tulsa Dental, Tulsa, OK), MTA Branco (Angelus Soluções Odontológicas, Londrina, PR, Brazil), MTA BIO (Angelus Soluções Odontológicas), or Portland cement with and without calcium chloride. METHODS: Dentin discs with standardized cavities were filled with ProRoot MTA, MTA Branco, MTA BIO, white Portland cement + 20% bismuth oxide (PC1), or PC1 + 10% of calcium chloride (PC2). The specimens were randomly divided into two groups: cement in contact with a wet cotton pellet for 72 hours or immersed in PBS for 2 months. The bond strengths were measured with the Instron Testing machine (Model 4444; Instron Corp, Canton, MA), and the fractured surfaces on the root walls were observed by scanning electron microscopy. RESULTS: All samples immersed in PBS displayed a significantly greater resistance to displacement than that observed for the samples in contact with a wet cotton pellet for 72 hours (p < 0.05). MTAs displayed a significantly greater resistance to displacement than Portland cements. CONCLUSION: It was concluded that the biomineralization process positively influenced the push-out bond strength of the cements, particularly the MTA groups.

Biomineralization ability and interaction of mineral trioxide aggregate and white portland cement with dentin in a phosphate-containing fluid.

INTRODUCTION: Mineral trioxide aggregate (MTA) has been shown to be bioactive because of its ability to produce biologically compatible carbonated apatite. This study analyzed the interaction of MTA and white Portland cement with dentin after immersion in phosphate-buffered saline (PBS). METHODS: Dentin disks with standardized cavities were filled with ProRoot MTA, MTA Branco, MTA BIO, white Portland cement + 20% bismuth oxide (PC1), or PC1 + 10% of calcium chloride (PC2) and immersed in 15 mL of PBS for 2 months. The precipitates were weighed and analyzed by scanning electron microscopy (SEM) and x-ray diffraction. The calcium ion release and pH of the solutions were monitored at 5, 15, 25, and 35 days. The samples were processed for SEM observations. Data were analyzed by using analysis of variance or Kruskall-Wallis tests. RESULTS: Our findings revealed the presence of amorphous calcium phosphate precipitates with different morphologies. The apatite formed by the cement-PBS system was deposited within collagen fibrils, promoting controlled mineral nucleation on dentin, observed as the formation of an interfacial layer with tag-like structures. CONCLUSIONS: All the cements tested were bioactive. The cements release some of their components in PBS, triggering the initial precipitation of amorphous calcium phosphates, which act as precursors during the formation of carbonated apatite. This spontaneous precipitation promotes a biomineralization process that leads to the formation of an interfacial layer with tag-like structures at the cement-dentin interface.