Osteopontin expression in co-cultures of human squamous cell carcinoma-derived cells and osteoblastic cells and its effects on the neoplastic cell phenotype and osteoclastic activation.

This study evaluated the temporal expression of osteopontin (OPN) in co-cultures of human osteoblastic cells (SAOS-2) and oral squamous cell carcinoma (OSCC)-derived cells (SCC9) and examined the effects of osteoblast-derived OPN on the neoplastic cell phenotype. Additionally, the effects of these co-cultures on subsequent osteoclastic activity were explored. SCC9 cells were plated on Transwell® membranes that were either coated or not coated with Matrigel and were then co-cultured with SAOS-2 cells during the peak of OPN expression. SCC9 cells exposed to OPN-silenced SAOS-2 cultures and SCC9 cells cultured alone served as controls. SCC9 cells were quantitatively evaluated for cell adhesion, proliferation, migration, and invasion into Matrigel. The impact of co-culturing SAOS-2 and SCC9 cells on the resorptive capacity of U-937-derived osteoclastic cells was also investigated. Furthermore, a reciprocal induction of SAOS-2 and SCC9 cells in terms of OPN expression over the co-culture interval was identified. SAOS-2-secreted OPN altered the SCC9 cell phenotype, leading to enhanced cell adhesion and proliferation and higher Matrigel invasion. This invasion was also enhanced, albeit to a lesser degree, by co-culture with OPN-silenced SAOS-2 cells. Cell migration was not affected. Co-culture with SAOS-2 cells-mainly during the period of peak OPN expression-promoted over-expression of IL-6 and IL-8 by SCC9 cells and enhanced the resorptive capacity of osteoclastic cells. Taken together, these results suggest that osteoblast-derived OPN affects the interactions among OSCC-derived epithelial cells, osteoblasts, and osteoclasts, which could contribute to the process of bone destruction during bone invasion by OSCC.

Gene expression of Candida albicans strains isolates from patients with denture stomatitis submitted to treatments with photodynamic therapy and nystatin.

The study evaluated the effect of antimicrobial photodynamic therapy (aPDT) and nystatin (NYS) in the expression of genes (ACT1, ALS1, CAP1, CAT1, EFG1, HWP1, LIP3, PLB1, SAP1, and SOD1) involved in the virulence of Candida albicans strains recovered from patients with denture stomatitis (DS). These strains were isolated from the patients before (initial) and after treatment (final), and 45 days after the treatments (follow-up). For gene expression analyses, RNA was isolated from the clinical strains, followed by cDNA synthesis and qPCR using specific primers for each target gene. The samples that present integrity were pooled to increase the RNA yield. In the end, four patients treated with aPDT and five patients treated with NYS had the clinical isolates of C. albicans submitted to gene expression evaluation. The data demonstrated a statistical difference in the expression of PLB1 and ACT1 for the different therapies (aPDT versus NYS). Also, there was a statistical difference in the expression of CAT1, SOD1, and LIP3 at the time intervals assessed (initial, final, and follow-up). In contrast, no statistical difference was found in the expression of ALS1, HWP1, EFG1, CAP1, CAT1, SOD1, LIP3, and SAP1 between the therapies, while no significant difference was detected at the time intervals evaluated for ALS1, HWP1, EFG1, CAP1, and SAP1. Therefore, the topical treatments for DS with aPDT or NYS did not effect the expression of most C. albicans virulence genes evaluated.

A randomized clinical trial evaluating Photodithazine-mediated Antimicrobial Photodynamic Therapy as a treatment for Denture stomatitis.

OBJECTIVE: This randomized clinical trial assessed antimicrobial Photodynamic Therapy (aPDT) mediated by Photodithazine (PDZ) to treat patients with denture stomatitis (DS). METHODOLOGIES: Patients with DS were randomly assigned to the groups: aPDT (n = 30) and nystatin (NYS, n = 35). aPDT patients received 6 aPDT sessions, three times a week for 15 days, which involved PDZ (200 mg/L) topical application (20 min) on the palate and upper denture, followed by LED illumination (660 nm, 50 J/cm²). NYS patients were instructed to rinse one dropper of this medication for one minute, four times a day, for 15 days. Microbiological collections of dentures and palates were performed and cultured on blood agar and CHROMAgar Candida. Microbial viability was determined, and photographs of the palates were taken for clinical evaluation. Data were analyzed by Repeated Measure Linear Model and Bonferroni (p ≤ 0.05). RESULTS: aPDT was more effective to reduce the total microbiota than NYS. At the end of the treatments, aPDT reduced 1.98 from the palate and 1.91 log10 from the denture, while NYS reduced 0.05 and 0.17 log10, respectively. Moreover, aPDT was as effective as NYS to reduce Candida. Reductions of 0.68 and 0.77 log10 were observed in the palate and denture of aPDT group, while reductions of 0.57 and 1.43 log10 were achieved in the NYS group, respectively. Regarding to oral lesion, 53.3 and 54.2 % of the patients from aPDT and NYS groups had clinical improvement. However, the recurrence of DS was observed in both groups. CONCLUSION: PDZ-mediated aPDT is a promising treatment for DS.

Antimicrobial Photodynamic Therapy mediated by Photodithazine® in the treatment of denture stomatitis: A case report.

Antimicrobial Photodynamic Therapy (aPDT) mediated by Photodithazine® (PDZ) has shown efficacy in the inactivation of Candida spp. in in vitro and in vivo studies. This preliminary study reports five clinical cases of patients with denture stomatitis (DS) treated with PDZ-mediated aPDT. Five individuals diagnosed with DS were selected and submitted to aPDT 3 times a week for 15 days (6 sessions). In each session, 200 mg/L of PDZ gel was applied on the upper prostheses and on the palate of the patients for 20 min, then, illuminated by a light emitting diode at 660 nm (50 J/cm2). Microbiological samples from prostheses and palates were also performed and cultured on Sabouraud Dextrose Agar and Blood Agar. The values ​​of colony forming units per milliliter (CFU/mL) were determined. Standardized photographs of the palates were taken prior the treatment (initial), at the end (final) and until 45 days after the completion of treatments. The results demonstrated that the aPDT treatment reduced Candida spp. and the total microbiota viability ​​at the end of the treatment. For most patients, the CFU/mL values obtained in the last microbiological collection (day 45) were lower than those found before the treatment (initial). Three patients presented clinical resolution of DS (no DS signal) after aPDT treatment. One individual demonstrated reduction in palatal inflammation and another one did not show improvement in the oral lesion. Recurrence of DS was observed in all individuals in the follow-up period. PDZ-mediated aPDT may be a promising treatment for DS.