Pleckstrin Homology Domain Leucine-rich Repeat Protein Phosphatase Acts as a Tumor Suppressor in Oral Squamous Cell Carcinoma

The pleckstrin homology domain leucine-rich repeat protein phosphatase (PHLPP) family has been found to have both tumor-suppressor and oncogenic properties across various types and locations of cancer. Given that PHLPP has not been previously studied in oral squamous cell carcinoma (SCC), we conducted an assessment of the expression of both its isoforms in oral SCC tissues and cell lines and compared these findings to their corresponding normal counterparts. In addition, we assessed the relationship between PHLPP and clinicopathological factors and patient survival. Quantitative real-time polymerase chain reaction was used to detect the mRNA levels of PHLPP1 and PHLPP2 in cancerous and normal cell lines in addition to 124 oral SCC and noncancerous adjacent epithelia (N = 62, each). Correlations between their expression rate and clinicopathological parameters were further evaluated in 57 patients. Data were statistically analyzed with t test and paired t test, analysis of variance, Mann-Whitney U , and Cox Regression tests ( P < 0.05). We found significantly lower levels of both PHLPP isoforms in oral SCC tissues compared with noncancerous epithelia ( P < 0.001, for both). However, in the cell lines, this difference was significant only for PHLPP1 ( P = 0.027). The correlation between the two isoforms was significant only in cancerous tissues ( P < 0.001). None of the clinicopathologic factors showed significant associations with either of the isoforms and there was no correlation with survival. We showed for the first time that PHLPP1 and PHLPP2 act as tumor suppressors in oral SCC at the mRNA level. The regulation of their mRNA appears to be different between normal and cancerous tissues.

Exploring the impact of naltrexone on the THBS1/eNOS/NO pathway in osteoporotic bile duct-ligated rats

Hepatic osteodystrophy, a prevalent manifestation of metabolic bone disease, can arise in the context of chronic liver disease. The THBS1-eNOS-NO signaling pathway plays a pivotal role in the maturation of osteoclast precursors. This study aimed to investigate the impact of Naltrexone (NTX) on bone loss by examining the THBS1-eNOS-NO signaling pathways in bile duct ligated (BDL) rats. Male Wistar rats were randomly divided into five groups (n = 10 per group): control, sham-operated + normal saline, BDL + normal saline, sham-operated + NTX (10 mg/kg), and BDL + NTX. Parameters related to liver injury were measured at the study's conclusion, and Masson-trichrome staining was employed to evaluate collagen deposition in liver tissue. Bone THBS-1 and endothelial nitric oxide synthase (eNOS) expression levels were measured using real-time PCR, while the level of bone nitric oxide (NO) was assessed through a colorimetric assay. NTX treatment significantly attenuated the BDL-induced increase in circulating levels of liver enzymes and bilirubin. THBS-1 expression levels, elevated after BDL, were significantly suppressed following NTX administration in the BDL + NTX group. Despite no alterations in eNOS expression between groups, the bone NO level, significantly decreased in the BDL group, was significantly reduced by NTX in the BDL + NTX group. This study partly provides insights into the possible molecular mechanisms in BDL-induced osteoporosis and highlights the modulating effect of NTX on these pathways. Further research is needed to establish the impact of NTX on histomorphometric indexes.

Erratum: Effect of amitriptyline on orthodontic tooth movement in rats: An experimental study

[This corrects the article DOI: 10.34172/joddd.2020.033.].

Antimicrobial Effects of Postbiotic Mediators Derived from Lactobacillus rhamnosus GG and Lactobacillus reuteri on Streptococcus mutans

BACKGROUND

Streptococcus mutans is a major component of dental plaque, contributing to cariogenic biofilm formation and inducing dental caries. Attempts have recently been made to use postbiotic mediators (PMs) to prevent dental caries. This research evaluated the antimicrobial/antibiofilm activity of PMs derived from Lactobacillus rhamnosus GG (LGG) and Lactobacillus reuteri (LR) against S. mutans in vitro.

METHODS

PMs were obtained from the Lactobacilli supernatants. The minimum inhibitory concentration, minimum bactericidal concentration, antibiofilm potential, and metabolic activity of PMs against S. mutans were evaluated using CFU/mL, scanning electron microscopy, and XTT (2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) reduction assay. The expression of gtfB gene as one of the most important genes involved in S. mutans biofilm formation was also measured using qRT-PCR.

RESULTS

CFU score was reduced by both PMs, but the reduction was only significant in LGG (p = 0.02). Both PMs caused a significant decrease in the metabolic activity of S. mutans compared with the controls (p ≤ 0.002). S. mutans treated with LGG PMs exhibited more destructive effects than LR PMs (p > 0.05). S. mutans gtfB gene expression was significantly downregulated when treated with the PMs obtained from both LGG and LR (p = 0.01 for both).

CONCLUSIONS

We showed that PMs isolated from two Lactobacillus strains inhibited S. mutans biofilm, metabolic activity, and gtfB gene expression. Therefore, these derivatives may be a suitable biofilm-destruction agent against S. mutants. However, the oral environment is a complex ecosystem that needs further investigation.

Efficacy of Synthesized Cubic Spirulina Platensis Photosensitizer in Anticancer Photodynamic Therapy: An in vitro study

Photodynamic therapy (PDT) is becoming increasingly popular in cancer management. Photosensitizers derived from natural sources can offer additional health benefits and play a crucial role in enhancing the efficacy of PDT in cancer treatment. We herein synthesized a cubic form of spirulina platensis (SP) and compared its anticancer-PDT efficacy with the naturally-occurring microhelical SP (MSP) and phycocyanin (Pc) against a tongue cancer cell-line and fibroblast cells. Cubic SP (CSP) was synthesized and characterized using standard analyses. CAL-27 and HGF cell-lines were incubated at different concentrations with each photosensitizer and were irradiated with 635 nm diode-laser. The viability, cellular-uptake, apoptosis and oxidative stress potential were quantitatively analyzed and statistically compared at P<0.05. Our results demonstrated that all three photosensitizers were non-toxic to normal cells before laser irradiation. In CAL-27, viability significantly decreased after PDT in all photosensitizer groups (P<0.05). Whereas, in HGF, Pc exhibited phototoxicity after laser irradiation (P=0.032). Cell-death was mainly apoptotic in Pc and CSP, but necrotic in MSP. Cellular-uptake was significantly higher in Pc, but was similar in MSP and CSP. Increase in reactive oxygen species was significantly higher in the Pc group compared to both SPs (P<0.05). We concluded that both SPs were safe and efficient photosensitizers for anticancer-PDT. CSP exhibited predominant and significant apoptotic death in CAL-27 and HGF cell-lines, while MSP mainly induced necrotic cell death. Despite the good photosensitizing performance of Pc, its use in higher concentrations should be considered with caution, due to the reduced viability that occurred following its use in PDT.

In Vitro Anti-tumor Effects of Photodynamic Therapy on Oral Squamous Cell Carcinoma: A Review

Introduction: Due to the increasing prevalence and high mortality rate of oral squamous cell carcinoma (OSCC) and problems with its routine treatments, more recent modalities like photodynamic therapy (PDT) have been developed. PDT effectively destroys tumor cells with minimum side effects. Research on in vitro effects of PDT may be helpful in determining the molecular mechanisms responsible for its effectiveness and can lead to the development of more efficient techniques. The aim of this study was to review the use of PDT in OSCC among in vitro studies. Methods: A literature search for English articles on PDT in OSCC was performed in PubMed, Scopus, Google Scholar, and Web of Science. Data were extracted based on the inclusion/exclusion criteria, which were detailed using the PICO framework: all eligible in vitro studies evaluating the effects of PDT on the viability of OSCC compared to controls without PDT were included. Results: Forty-one out of 567 studies were selected. The tongue was the most common OSCC site, 5-aminolevulinic acid was the most used photosensitizer (PS), cell viability/toxicity and apoptosis were the most evaluated outcomes, and lasers with wavelengths of 600-700 nm were the most common light sources and wavelengths respectively. Conclusion: PDT showed promising effects on reducing the viability of OSCC cells. Cell lines from various sources or even those originating from the same location sometimes responded differently to the same protocol. Considering the favorable results obtained from natural PSs and regarding their additional health-promoting properties, their use in future investigations with different cell lines and light specifications is recommended.

Clinical prognostic value of the SMYD2/3 as new epigenetic biomarkers in solid cancer patients: a systematic review and meta-analysis

BACKGROUND

SET and MYND domain-containing protein (SMYD) family with methyltransferase activity is involved in cancer progression. This novel meta-analysis aimed to evaluate the association of SMYD family with the clinical and survival outcomes in solid cancer patients.

METHODS

We systematically searched Embase, PubMed, Scopus and Web of Science to select relevant articles. Hazard ratios (HRs), odds ratios (ORs), and 95% confidence intervals were extracted. Heterogeneity was evaluated by chi-square-based Q and I2 tests, while publication bias by funnel plots and Egger's test.

RESULTS

Thirty-two articles (4,826 patients) met inclusion criteria. SMYD2/3 overexpression was statistically associated with poor overall survival (HR = 1.794, P < 0.001), disease/relapse/progression-free survival (HR = 2.114, P < 0.001), disease/cancer-specific survival (HR = 3.220, P = 0.003), larger tumor size (OR = 1.963, P < 0.001), advanced TNM stage (OR = 2.066, P < 0.001), lymph node metastasis (OR = 2.054, P < 0.001), and distant metastasis (OR = 1.978, P = 0.004). Subgroup analysis showed more significant association between SMYD2 overexpression and reduced survival outcomes than that in SMYD3. Conversely, the relationship between SMYD3 and various clinicopathologic factors was stronger compared to SMYD2.

CONCLUSION

Enhanced SMYD2/3 expression may be an unfavorable clinical prognostic factor in different solid cancer types.

Distinctive expression of DNA replication factors in squamous cell carcinomas of the lip, face and oral cavity

OBJECTIVE

Uncontrolled proliferation and aberrations in cell-cycle progression are fundamental issues in cancer. In this study we aimed to determine and compare deoxyribonucleic acid (DNA) replication licensing factors at the mRNA and protein levels among squamous cell carcinomas (SCCs) of the lip, facial-skin and oral cavity.

MATERIALS AND METHODS

A total of 103 lip, oral and face SCCs were immunohistochemically stained with MCM2 (mini-chromosome maintenance 2), geminin, and ki67, and their labeling-indices were calculated. Also, 57 SCCs from the same regions along with their adjacent normal tissues underwent quantitative reverse transcription-polymerase chain reaction analysis.

RESULTS

All three proteins were overexpressed in the studied SCCs, but only geminin (P = 0.004) showed significant difference among the three regions, with higher levels in oral SCCs compared to lip (P = 0.005) and skin (P = 0.024) tumors. Geminin expression did not differ between skin- and lip-SCCs (P = 0.822). MCM2/ki67 ratio was higher in oral- compared to skin-neoplasms (P = 0.039), but no difference was found in geminin/ki67 among the SCC-subsites. There were significant differences in MCM2 and geminin mRNA between carcinomatous- and normal-tissues in all tumors, but not among the three locations.

CONCLUSION

MCM2 and geminin are involved in the tumorigenesis of lip, face and oral SCC at both mRNA- and protein-levels. Geminin may have a role in the site-specific biologic behavior of SCC. Skin SCCs had the highest proportion of licensed non-proliferating cells, while actively proliferating cells were more prominent in oral tumors. Regarding DNA replication, lip SCCs seem to be closer to skin tumors compared to their oral counterparts.

SARS-Cov-2 infection in cancer patients, susceptibility, outcome and care

The COVID-19 pandemic has led to many problems in cancer patients, which in part are due to insufficient knowledge of the exact implications of the virus on these individuals. Perceptions based on known facts about previous pandemics and coronaviruses might not agree with actual real-life experience and objective findings. We present a compilation of scientific facts and actual observations on different aspects of SARS-CoV-2 infection in cancer patients. These patients are at increased risk of viral contraction and have higher chances of severe disease/mortality. The latter is impacted by other factors and is still debated. In contrast to preliminary impressions, the benefits of anti-cancer treatments outweigh their risks and should be continued. Cancer patients generate antibodies in response to vaccination but in lower amounts than healthy people, especially those with hematologic cancers. Boosters, including third doses, have shown increased immune-responses in most patients. Vaccination should be prioritized in these individuals.

DNA-aptamer-nanographene oxide as a targeted bio-theragnostic system in antimicrobial photodynamic therapy against Porphyromonas gingivalis

The aim of this study was to design and evaluate the specificity of a targeted bio-theragnostic system based on DNA-aptamer-nanographene oxide (NGO) against Porphyromonas gingivalis during antimicrobial photodynamic therapy (aPDT). Following synthesis and confirmation of NGO, the binding of selected labeled DNA-aptamer to NGO was performed and its hemolytic activity, cytotoxic effect, and release times were evaluated. The specificity of DNA-aptamer-NGO to P. gingivalis was determined. The antimicrobial effect, anti-biofilm potency, and anti-metabolic activity of aPDT were then assessed after the determination of the bacteriostatic and bactericidal concentrations of DNA-aptamer-NGO against P. gingivalis. Eventually, the apoptotic effect and anti-virulence capacity of aPDT based on DNA-aptamer-NGO were investigated. The results showed that NGO with a flaky, scale-like, and layered structure in non-cytotoxic DNA-aptamer-NGO has a continuous release in the weak-acid environment within a period of 240 h. The binding specificity of DNA-aptamer-NGO to P. gingivalis was confirmed by flow cytometry. When irradiated, non-hemolytic DNA-aptamer-NGO were photoactivated, generated ROS, and led to a significant decrease in the cell viability of P. gingivalis (P < 0.05). Also, the data indicated that DNA-aptamer-NGO-mediated aPDT led to a remarkable reduction of biofilms and metabolic activity of P. gingivalis compared to the control group (P < 0.05). In addition, the number of apoptotic cells increased slightly (P > 0.05) and the expression level of genes involved in bacterial biofilm formation and response to oxidative stress changed significantly after exposure to aPDT. It is concluded that aPDT using DNA-aptamer-NGO as a targeted bio-theragnostic system is a promising approach to detect and eliminate P. gingivalis as one of the main bacteria involved in periodontitis in periopathogenic complex in real-time and in situ.

Clinicopathologic significance of DNA replication licensing factors in head and neck diffuse large B-cell lymphoma

OBJECTIVE

Diffuse large B-cell lymphoma (DLBCL) harbors defects in the proliferation pathway. We performed multiparameter analysis of proteins expressed during different cell cycle phases and correlated them with clinical parameters of head and neck DLBCLs.

STUDY DESIGN

Thirty-nine DLBCLs were staged and immunohistochemically stained with MCM2, Ki67, and geminin. The receiver operating characteristic curve and its area under the curve were calculated, and sensitivity vs specificity curve analysis was performed.

RESULTS

The highest labeling index was in MCM2, followed by Ki67 and geminin (P < .001). All pairs showed significant differences (P < .001). The best cutoff points to differentiate limited from advanced disease were 68% and 45% for MCM2 and Ki67, respectively. There was no acceptable cutoff for geminin (area under the curve = 0.667, P = .134). MCM2/Ki67 (P = .293) and geminin/Ki67 (P = .233) ratios did not differ between the stages. The median (interquartile range) of the geminin/Ki67 ratio was 0.57 (0.68), translating to a reduced G1.

CONCLUSIONS

We suggest a role for cell cycle-related proteins in the biology and behavior of DLBCLs. MCM2 and Ki67 cutoffs can be a potential option to differentiate limited from advanced disease, where imaging and laboratory techniques are unavailable. The G1 decrease and the significantly higher MCM2 expression compared to Ki67 indicate replication disturbances, making factors involved in the G1 phase targets for treatment.

The anti-inflammatory effect of dapsone on ovalbumin-induced allergic rhinitis in balb/c mice

AIMS

Allergic rhinitis (AR), a major chronic inflammatory disease of the respiratory system, is a public health issue because of its substantial negative impact on quality of life and work efficiency alongside its high prevalence and costs. Dapsone is a sulfone chemical with reported anti-inflammatory and antibacterial properties. Accordingly, we investigated the anti-inflammatory impact of dapsone on ovalbumin-induced allergic rhinitis in balb/c mice.

MAIN METHODS

Intraperitoneal ovalbumin and hydroxide aluminum injection followed by intranasal ovalbumin administration sensitized female Balb/c mice. Mice received intraperitoneal dapsone either acute (5, 10, 20 mg/kg) 30 min before the last ovalbumin challenge, or chronic (20 mg/kg) on days 21 to 35.

KEY FINDINGS

Both acute and chronic intraperitoneal usage of dapsone showed a considerable decrease in the nasal scratching behavior, the number of sneezing, serum IL-4 and IgE levels of ovalbumin-induced AR in balb/c mice, but there was a significant increase in serum IFNγ level. Histopathological analysis demonstrated a significant reduction of eosinophil numbers, following dapsone injection. Goblet cell hyperplasia and respiratory epithelial-thickness decreased significantly in the acute and chronic 20 mg/kg dapsone groups compared to the ovalbumin-induced controls.

SIGNIFICANCE

This study shows that there is an association between acute and chronic dapsone treatment and some anti-allergic effects through an inflammation cascade.

The effect of photodynamic therapy on head and neck squamous cell carcinoma cell lines using spirulina platensis with different laser energy densities

BACKGROUND

Considering the anti-cancer properties of spirulina platensis (S. platensis), we aimed to investigate the effectiveness of this algae as a novel natural photosensitizer for photodynamic therapy (PDT) against oral and hypopharyngeal cancer cells. The appropriate laser energy density to apply during PDT was also determined.

METHODS AND MATERIALS

CAL-27, FaDu and HGF cell lines were exposed to S. platensis with concentrations of 0.3 g/l and 0.6 g/l and were irradiated with 635 nm diode laser using 2, 4, 12, and 24 J/cm² energy densities with constant power. MTT assay was performed to investigate cell viability and cytotoxicity after 24 h. The results were analyzed using two-way ANOVA and post hoc Tukey tests (P-value<0.05).

RESULTS

survival rate in CAL-27 (P-Value<0.001) and FaDu (P-Value<0.001) cell lines were significantly different following irradiation with various laser energy densities. Different concentrations of S. platensis had no significant effect on the viability of CAL-27 cells (P-Value=0.158) and FaDu cells (P-Value=0.072) and showed no significant cytotoxicity against HGF cells, with or without laser.

CONCLUSION

S. platensis could be considered as a novel safe and effective natural photosensitizer for cancer PDT with no cytotoxic effect on normal cells. When combined with laser using appropriate energy densities, it has the ability to induce death in oral and hypopharyngeal cancer cell lines.

Comparison between the Effect of 810 nm and 940 nm Diode Laser Irradiation on Histopathological Changes in Iatrogenic Oral Ulcers: an Animal Study

STATEMENT OF THE PROBLEM

Considering the relatively high prevalence of oral mucosal ulcers, their fast healing is of significance.

PURPOSE

This study aimed to histopathologically compare the effects of 810 nm and 940 nm diode laser on the healing of iatrogenic oral ulcers in rabbits.

MATERIALS AND METHOD

In this single-blind experimental study, mucosal ulcers measuring 3mm in diameter and 1mm in depth were bilaterally created in the buccal mucosa of 18 rabbits using a biopsy punch. The defects were irradiated with 810 nm diode laser on the right side and 940 nm diode laser on the left side. Biopsy samples of the same depth were obtained from the ulcers on days 3 and 7 followed by histopathological analysis. The intensity of inflammation was determined on hematoxylin-eosin-stained sections using a four-point scale. Data were analyzed employing the Wilcoxon signed rank test.

RESULTS

The degree of inflammation was not significantly different between the 810nm and 940nm diode laser groups on day 3; but on day 7, animals receiving 810 nm experienced a significantly lower degree of inflammation compared to those treated with 940 nm laser (p= 0.028).

CONCLUSION

When comparing 810- and 940-nm diode lasers, 810 nm irradiation significantly decreased the severity of inflammation in oral wounds created on the buccal mucosa of rabbits in a time-dependent manner.

Modulation of the triggered apoptosis by nano emodin transfersome-mediated sonodynamic therapy on head and neck squamous cell carcinoma cell lines

BACKGROUND

Non-invasive sonodynamic therapy (SDT) is a new treatment modality that uses low-intensity ultrasound to activate a non-toxic sensitizing chemical agent for cancer therapy in a site-directed manner. This study aimed to investigate the anti-cancer effects of ultrasound combined with nano emodin transfersome (NET) on head and neck squamous cell carcinoma (HNSCC) cell lines.

MATERIALS AND METHODS

A transfersome form of nano emodin as a novel sono-responsive nanomaterial was synthesized to enhance the accumulation and penetration of nanoparticles. iIn vitro experiments including hemolytic activity, cell proliferation, intracellular reactive oxygen species (ROS) generation, apoptosis induction, DNA fragmentation, and mRNA expressions of caspase 3 and 9 were conducted to explore the anti-cancer effects of NET-SDT on FaDu and CAL-27 cell lines.

RESULTS

Characterization tests showed the round and uniform morphology of NET with transfersome structure, resulting in a high drug-loading content and encapsulation efficiency. No significant hemolytic activity was observed (P > 0.05). Cytotoxicity gradually increased with increasing concentrations of NET, so that 10 × 10^-4 g/L of NET plus 5 min ultrasound irradiation at a frequency of 1 MHz and ultrasonic intensity of 2 W/cm² effectively killed 98.2 % and 97.3 % of FaDu and CAL-27 cell lines, respectively (P < 0.05). We found that ROS generation in NET-SDT was dose-dependent and the triggered apoptosis and caspase-3/9 gene expression levels were significantly enhanced as the concentration of NET increased (P < 0.05). No significant difference was found in the rate of apoptosis induction and gene expression between two cell lines.

CONCLUSIONS

Our data demonstrated that SDT with NET as a sonosensitizer can induce apoptosis and significantly decrease cell viability of HNSCC cell lines, which represents the role of NET-SDT as a potent anti-cancer modality.

The Effect of Laser Bio-modulation on Dysplastic Lesions, an Animal Study

Potentially malignant disorders are one of the clinical challenges. Dysplasia in these lesions can be a predictor of more potential for malignant changes. Photo-bio-modulation in benign lesions has advantages, but there is doubt on its safety in potentially malignant lesions. This study aims to assess if low-level laser can promote dysplastic changes while the method can play an important role in management of dysplastic lesions. Dysplasia was induced on anterior wall of the buccal pouch of 80 young Syrian male hamsters. Then, hamsters were divided to four groups to receive 4 and 12 sessions irradiation of 660 and 810 nanometers low-level lasers. For histopathologic study of the tissue, we used light microscopes. Using SPSS, data were analyzed via Wilcoxon signed rank test and Mann-Whitney U-test. In all of our four groups, the severity of dysplasia had no statistical difference in study sides comparing with their own controls. Wavelength and numbers of laser irradiation sessions had no statistically meaningful effect on the severity of dysplasia either. Low-level lasers appear to show no relevant or significant effect over the aggravation of the dysplasia's severity. Neither the wavelength nor the number of sessions appear to have any impact in the results.

Conditioned media derived from mesenchymal stem cells induces apoptosis and decreases cell viability and proliferation in squamous carcinoma cell lines

Squamous cell carcinoma (SCC) is a relatively common cancer with a low survival rate, poor prognosis and no effective treatment strategy. The use of cell-free conditioned media derived from mesenchymal stem cells (CM-MSCs) has shown promising results in treating various diseases. This study aimed to evaluate the effects of CM-MSCs on proliferation and apoptosis of CAL-27 and FaDu SCC cell lines. CM derived from human bone marrow and human amniotic membrane MSCs (BM-MSCs and AM-MSCs) was used in this investigation. MTT assay demonstrated that CM-BMMSC decreased the viability of CAL-27 and FaDu cell lines, 24, 48, and 72 h after treatment. Quantitative real-time PCR indicated that mRNA expression of PCNA as a proliferative marker, and BCL-2 as an anti-apoptotic protein, decreased in both cell lines treated with CM-BMMSC. Based on the flow cytometry results, the number of positive proliferative Ki67 cells and apoptotic Annexin-V cells decreased and increased in both cell lines treated with CM-BMMSC, respectively. However, CM-AMMSC treatment had both pro-and anti-neoplastic effects in our samples and showed considerable differences between the two cell lines. Taken together, our findings demonstrated that CM-BMMSC and, to a lesser degree, CM-AMMSC decrease cell viability and proliferation and increase cell apoptosis in SCC cell lines in a time-dependent manner. However, further studies are needed, especially to evaluate the anti-tumor potential of CM-BMMSC in vivo.

Comparison of routine and microwave-assisted decalcification of bone with or without teeth: A histologic study

BACKGROUND

The aim of this study was to compare conventional and microwave-assisted decalcification of sheep bone with and without teeth and to detect any difference in tissue detail preservation, staining quality, and rate of decalcification.

MATERIALS AND METHODS

In this method analysis study, twenty-four specimens consisting of 12 blocks of mandibular molars with their surrounding bone and 12 blocks of mandibular osseous tissue were allocated into two microwave or routine decalcification groups using 5% nitric or formic acid as decalcifying agents. In addition to decalcification rate, a number of variables were used to assess staining quality and tissue detail preservation which were compared between the two groups using Mann-Whitney test (P < 0.05).

RESULTS

Time to complete decalcification was significantly reduced in the microwave-treated samples as compared to the conventional method, regardless of the decalcifying agent (P = 0.025). For both acids, most variables related to staining quality and tissue detail preservation were similar between the techniques (P > 0.05). Patchy staining in bone samples and tissue tears in bone + teeth specimens were more common in the routine method when using nitric acid (NAc) (P = 0.046) and formic acid (FAc) (P = 0.046), respectively. In comparing acids, the performance of FAc was slightly inferior to that of NAc, especially for specimens containing both tooth and bone.

CONCLUSION

The use of microwave technology can accelerate decalcification of bone and teeth of sheep mandibles and at the same time preserve tissue structure and staining quality. Further studies are required to help select the best demineralizing agent, especially in specimens containing bone and teeth.

Cell kinetic markers in cutaneous squamous and basal cell carcinoma of the head and neck

Introduction

Proliferation markers play a significant role in the biologic behavior of tumors. Geminin is a known inhibitor of the cell cycle and DNA replication and has not been previously reported in cutaneous basal and squamous cell carcinomas of the head and neck.

Objectives

We aimed to investigate proliferation markers ki67, MCM2, and geminin in head and neck cutaneous basal and squamous cell carcinomas.

Methods

Forty cases of each tumor were immuostained with ki67, MCM2, and geminin followed by assessment of labeling indices (LIs). MCM2/ki67- and geminin/ki67-ratios were also determined; t-test was used for statistical analysis (p < 0.05).

Results

There was no significant difference in ki67 (p = 0.06) and MCM2 (p = 0.46) between cutaneous basal and squamous cell carcinomas; however, geminin LI was significantly higher in squamous cell carcinomas compared to cutaneous basal cell carcinomas (p < 0.001). Only geminin/ki67 showed a significant difference between the two tumors with the ratio showing significantly higher numbers in squamous cell carcinomas (p = 0.015).

Conclusions

Geminin could be regarded as an effective factor in the pathogenesis of head and neck cutaneous cutaneous basal cell carcinomas and squamous cell carcinomas and may be one of the responsible elements in the difference between the biologic behavior of these tumors.

Novel osteoprotective nanocochleate formulation: A dual combination therapy-codelivery system against glucocorticoid induced osteoporosis

Phosphatidylserine nanocochleates (Nanocochs) are novel delivery systems that may play a prominent osteoprotective role with their cargo, vitamin D3 (Vit-D3), against osteoporosis. Therefore, this study was conducted to characterize a Nanococh containing vitamin D3 (Nanococh-D3) and investigate its potential role in improving GIO in a rat model. Roll-shaped Nanococh-D3 particles were obtained in a size range of 320 nm with a sustained release performance. Oral Nanococh-D3 significantly increased the bioavailability of Vit-D3, enhanced bone mechanical strength, and improved osteogenic biomarkers including B-ALP, osteocalcin, Ca, and OPG in GIO rats. This formulation markedly suppressed gene expression of RANK and RANKL in treated rats. Histomorphometric analysis showed significant repairs in bone tissues and TRAP staining indicated a significant decrease in osteoclasts using Nanococh-D3 in osteoporotic rats. Nanococh alone similar to Nanococh-D3 acted better than AL as a standard anti-osteoporotic drug in the improvement of bone strength. In conclusion, our results established the potential role of Nanococh-D3 against osteoporosis in rats.

Angiogenesis and Mast Cells Density in Oral and Esophageal Squamous Cell Carcinomas

Despite the similarities between oral and esophageal squamous cell carcinomas (SCCs), the survival rate of this cancer is relatively low in the esophagus compared to the oral cavity. To our knowledge, mast cells and angiogenesis have not been simultaneously compared between oral and esophageal SCCs. However, they have been separately evaluated in each of these locations with conflicting results. Therefore, the aim of this study was to assess and compare mast cell count and microvessel density between SCCs of the esophagus and oral cavity. A total of 46 oral and esophageal SCCs (23 of each) were stained immunohistochemically and histochemically with CD31 and methylene blue, respectively. Statistical analysis was performed using t-test, one-way ANOVA, and Pearson correlation analysis. Microvessel density was significantly higher in oral compared to esophageal tumors (P=0.02). Conversely, esophageal SCCs showed significantly higher mast cell counts than that of oral neoplasms (P=0.04). Pearson correlation analysis showed no association between these two factors in either oral SCC (P=0.51) or esophageal SCC (P=0.34). A significant difference between mean mast cell count and microvessel density in oral and esophageal SCC may be related to inherent differences in the tissues of origin and might, to some extent, be responsible for the different biological behaviors of these cancers. © 2019 Tehran University of Medical Sciences. All rights reserved. Acta Med Iran 2019;57(10):575-580.

Metformin loaded phosphatidylserine nanoliposomes improve memory deficit and reduce neuroinflammation in streptozotocin-induced Alzheimer's disease model

Alzheimer's disease (AD) is closely associated with neuroinflammation development in the brain. Co-delivery of metformin (MET) with phosphatidylserine liposomes neuroprotectant may be beneficial in ameliorating AD-related symptoms like memory impairment and inflammation. Therefore, we aimed to prepare metformin containing phosphatidylserine nanoliposomes formulation (MET-PSL) and to evaluate its effect on rats subjected to AD. Alzheimer's disease model was induced by bilateral intracerebroventricular injection of streptozotocin (3 mg/kg) into rat brains using the stereotactic technique. MET-PSL, MET, and PSL alone were administered intraperitoneally to AD-induced animals and factors including learning and memory storage in addition to cytokine and tissue inflammatory changes were evaluated after a 22-day experiment period. The learning and memory parameters significantly (P < 0.05) improved in AD-rats treated with MET-PSL. Moreover, MET-PSL administration significantly (P < 0.05) decreased cytokine levels of IL1-β, TNF-α, and TGF-β in hippocampal tissues of rats with AD. Histological results indicated a considerable reduction in inflammatory and necrotic neural cells along with significantly (P < 0.05) increased neurogenesis in MET-PSL treated rats. Furthermore, our results showed that MET-PSL formulation could potentially act better than the free form of MET and PSL alone in the recovery process of rats with AD. In general, our data suggest that combination therapy of metformin loaded phosphatidylserine liposomes may enhance the therapeutic performance in AD patients of a clinical study.

A Model for Induction of Dysplasia in Hamster Mucosal Pouch

Induction of premalignant lesions in animal models is of high value for research purposes. This study aimed to induce dysplasia in hamster mucosal pouch for investigation of dysplastic lesions using dimethylbenz(a)anthracene. The buccal pouch of 10 hamsters was painted with dimethylbenz(a)anthracene for 10 weeks every other day. At 5 and 10 weeks, they underwent histopathological analysis. Clinically, there was no change until week 7; after which mucosal thickening occurred. Hamsters scarified at 5 weeks and 10 weeks demonstrated mild and moderate dysplasia, respectively. dimethylbenz(a)anthracene is a useful tool for inducing dysplastic lesions in the buccal pouch mucosa of hamsters.

Photodisinfection effects of silver sulfadiazine nanoliposomes doped-curcumin on Acinetobacter baumannii: a mouse model

Aim: To evaluate the antimicrobial effects of photoexcited silver sulfadiazine nanoliposomes (AgSD-NLs) doped by curcumin (AgSD-NLs@Cur) on Acinetobacter baumannii. Materials & methods: Following characterization, the cytotoxic and hemolytic activities of AgSD-NLs@Cur were evaluated. The antimicrobial activities of AgSD-NLs@Cur-mediated antimicrobial photodynamic therapy (aPDT) were determined. Histopathological examination of the burn wound sites of infected mice treated with photoexcited AgSD-NLs@Cur was assessed. Results: No significant cytotoxic and hemolytic activities were observed. There was a decrease in the Acinetobacter baumannii count in planktonic and biofilm forms and the gene expression level using AgSD-NLs@Cur-aPDT (p < 0.05). Histopathological analysis indicated the epidermis developed markedly and the bacterial load decreased significantly after aPDT. Conclusion: Photoexcited AgSD-NLs@Cur has an antimicrobial potential against A. baumannii.

Stromal and epithelial syndecan-1 expression in benign and malignant salivary gland tumors: which is more reflective of behavior?

INTRODUCTION

Salivary gland tumors are a diverse group of lesions, with various origins and extremely different behaviors, leading to a variety of outcomes for patients. Therefore, the need to discover novel markers with the ability to predict the behavior of benign and malignant salivary gland neoplasms is crucial. Syndecan-1 is a cell-surface protein with significant roles in various aspects of tumor function. Its expression in salivary gland neoplasms, especially their stromal component, has not been investigated.

OBJECTIVES

We aimed to assess the immunopositivity of syndecan-1 in epithelial and stromal components of salivary gland neoplasms and to compare it between benign and malignant subtypes in addition to evaluating its correlation with clinicopathologic parameters.

METHODS

133 salivary gland tumors were immunohistochemically stained with syndecan-1 and the intensity and percentage of this protein was determined, compared between the tumors and correlated with clinicopathologic factors.

RESULTS

Statistical analysis of lesions with a sufficient sample size showed significant differences in percentage and intensity between both epithelial and stromal components of all tumors (p<0.05). Pairwise-comparisons demonstrated significantly higher staining-percentage of epithelial cells (p=0.02) in Warthin's tumor compared to pleomorphic adenoma and adenoid cystic carcinoma. Similarly, significantly higher staining intensities and/or percentages was observed in mucoepidermoid carcinoma and adenoid cystic carcinoma compared to pleomorphic adenoma and Warthin's tumor (p<0.05). Of the clinicopathologic factors, there was only a significant negative correlation between stromal percentage of mucoepidermoid carcinoma and age and a significant difference between stromal intensity+percentage of adenoid cystic carcinoma and gender (p<0.05).

CONCLUSIONS

According to our findings we postulate that stromal syndecan-1 correlates with the behavior of salivary gland tumors, with malignant neoplasms demonstrating a higher expression, indicating a role for syndecan-1 in invasion and metastasis.

Upregulation of ADAM10 in oral squamous cell carcinoma and its correlation with EGFR, neoangiogenesis and clinicopathologic factors

ADAM10 (a disintegrin and metalloproteinase-10) is a known sheddase for EGFR (epidermal growth factor receptor) ligands and has been suggested to modulate angiogenesis. We aimed to evaluate the expression of ADAM10 in patients with oral squamous cell carcinoma (OSCC) and to determine its correlation with EGFR, CD105 and clinicopathologic parameters. Fifty primary OSCCs with clinical data were graded according to the histologic risk assessment (HRA) model and subjected to immunohistochemical staining using antibodies against ADAM10, EGFR1 and CD105. ADAM10 was assessed in both epithelial and stromal components. The associations among all three proteins and clinicopathologic factors including tumor size, lymph node status and distant metastasis (TNM) were statistically analyzed (P < 0.05). Epithelial-ADAM10, stromal-ADAM10 and EGFR were overexpressed in 92%, 40% and 56% of the OSCCs, respectively. EGFR expression occurred in peripheral and diffuse patterns, which were also separately considered in our analyses. A significant correlation was found between ADAM10 and CD105 (r = -0.455; P < 0.001). Lymphocytic infiltration scores (P = 0.04) and tumor size (P = 0.001) showed significant differences between EGFR+ and EGFR- tumors, but none of the other variables had any relationships with either clinicopathologic factors or each other (P > 0.05). ADAM10 was upregulated in OSCC but had no correlation with survival-associated factors such as TNM or the HRA model. At the protein level, epithelial ADAM10 negatively regulated neoangiogenesis, but its interaction with EGFR was minimal. Reduction in host immunologic responses was associated with a decrease in EGFR. These findings, if corroborated, could be interesting in combination therapies used for cancer treatment.

Is podoplanin expression associated with transforming growth factor-β signaling in odontogenic cysts and tumors?

BACKGROUND

Induction of podoplanin by transforming growth factor-β (TGF-β) has been shown in a number of lesions but not in odontogenic tumors (OTs). We evaluated the association between these markers in OTs for the first time and compared their expression among the different neoplasms.

METHODS

Immunohistochemistry using monoclonal antibody against podoplanin and TGF-β was performed on 76 odontogenic cysts and tumors. Spearman's correlation coefficient, Kruskal-Wallis, and Mann-Whitney U tests followed by adjustment with Bonferroni were used for statistical analysis (P < .05).

RESULTS

A significant difference in podoplanin expression was found among the lesions consisting of solid ameloblastomas, adenomatoid odontogenic tumors, ameloblastic fibromas, odontogenic myxomas (OMs), odontogenic keratocysts, and calcifying odontogenic cysts. Significant differences were observed only between OMs and each of the other neoplasms. Podoplanin immunostaining in the connective tissue was absent in most lesions. TGF-β was significantly different among the study sample but not between the lesions in paired comparisons. None of the studied OTs showed significant correlations between podoplanin-TGF-β, in either the epithelium or the stroma. These markers were also descriptively reported in calcifying epithelial odontogenic tumors.

CONCLUSIONS

The inductive effect of TGF-β on podoplanin seems to be limited, if any, in odontogenic lesions. Podoplanin appears to play a role in some aspects of OTs with epithelial or mixed origins. Despite the possible participation of podoplanin in tumorigenesis, it may not necessarily be involved in the aggressive behavior of OTs.

A study on OPG/RANK/RANKL axis in osteoporotic bile duct-ligated rats and the involvement of nitrergic and opioidergic systems

Chronic liver disease (CLD) affects millions of people and its impact on bone loss has become a subject of interest. Nitric oxide and endogenous opioids are suggested to increase during cholestasis/cirrhosis and may impact bone resorption by different mechanisms. The receptor activator of nuclear factor-κB (RANK)/RANK-ligand (RANKL)/osteoprotegerin (OPG) signaling pathway regulates bone resorption, but its role in metabolic bone disease subsequent to CLD is unknown. We aimed to investigate the involvement of nitrergic and opioidergic systems in bone loss relative to the RANK/RANKL/OPG pathway, in bile duct-ligated (BDL) rats. Eighty BDL/sham-operated (SO) rats received injections of 3 mg/kg/day Nω-Nitro-L-arginine methyl ester ± naltrexone (10 mg/kg/day) or saline for 28 days. Plasma bone turnover markers, OPG, RANK, and RANKL along with mRNA expression levels of the latter three were assessed. Plasma bone turnover markers and OPG level increased, but RANKL decreased in the BDL group compared with their SO controls (both: P ≤ 0.05). Administration of naltrexone reduced bone turnover markers and OPG level while increased RANKL content in comparison to BDL rats (P ≤ 0.05). As compared to untreated BDL rats, nitric oxide inhibition showed no effect on bone turnover marker i.e. OPG, RANK, and RANKL levels. BDL significantly increased RANK mRNA, but had no significant effect on RANKL and OPG mRNA expression. The lack of association between plasma levels and quantitative gene expression of RANKL and OPG suggests an indirect function of these markers in BDL rats. Considering that opioid receptor blockage by naltrexone in BDL animals caused a significant decrease in OPG and an increase in RANKL plasma contents, it could be postulated that the opioidergic system may have a regulatory effect on these bone markers.

Comparison of the histologic risk assessment model between lower lip and oral squamous cell carcinoma

INTRODUCTION

The histologic risk assessment (HRA) grading system was proposed as a practical measure to predict clinical outcome and its effectiveness has been shown in several studies. It has been suggested that the HRA model might exhibit differences among various oral subsites. The aim of the present study was to compare this system between squamous cell carcinomas (SCCs) of the lower lip (LL) and oral cavity.

MATERIALS AND METHODS

All primary SCCs located in the LL and oral cavity were retrieved and graded using the HRA model. Data regarding risk score (RS), perineural invasion (PNI), lymphocytic infiltration (LI) and worst pattern of invasion (WPOI) were compared between LL and oral SCCs using χ² analysis (P<0.05).

RESULTS

There were a total of 33 LLSCCs, of which 15, 8 and 10 were categorized as low-risk (RS=0), intermediate-risk (RS=1-2) and high-risk (RS≥3) tumors, respectively. Corresponding values in the 48 oral SCCs were 7, 15 and 26 cases. Significant differences in RS (P=0.00), LI (P=0.01) and WPOI (P=0.01) were observed between LL and oral tumors.

CONCLUSIONS

The HRA model could be included among the various factors suggested to be different between lip and oral SCCs. Low-risk tumors were more prevalent in the lip which corroborates the less aggressive nature of these cancers. Considering the significantly higher LI in LL SCCs, inflammation may be regarded as an important factor in regulating the invasive behavior of these tumors.

Pattern of invasion in squamous cell carcinomas of the lower lip and oral cavity

Background

A number of factors may be responsible for the differences in the biologic behaviors of oral and lower lip squamous cell carcinomas (SCCs). Immunohistochemical invasion profiles have been used to detect invasion patterns like epithelial-mesenchymal-transition (EMT) and collective-cell-invasion (CCI), which have not been investigated in lower lip neoplasms. The aim of the present study was to compare the invasive phenotypes of SCCs of the lower lip and oral cavity.

Method

A total of 44 OSCCs and 37 lower lip SCCs were immunostained with E-Cadherin, N-Cadherin, and podoplanin. Based on their expression patterns, tumors were allocated to EMT, CCI or non-EMT/non-CCI categories.

Results

None of the oral SCCs showed EMT; while 5 lower lip SCCs demonstrated this phenotype. CCI was observed in 12 oral SCCs and 4 lower lip SCCs. The third group included 32 and 28 cases of oral and lower lip tumors, respectively. A significant difference in invasive phenotype was found between the two locations (P = 0.009).

Conclusion

Oral cavity and lip tumors differ in various aspects and according to our results; the pattern of invasion may be added to these features. Between the two major invasion patterns, EMT was more prevalent in lip tumors while CCI was observed more commonly in oral neoplasms. The significance of the different expression patterns of the non-EMT/non-CCI category requires further investigation.

The effect of caffeine on orthodontic tooth movement in rats

Objective(s):

to determine the effect of different doses of caffeine on orthodontic tooth movement (OTM) in rats.

Materials and Methods:

Forty male 250-300 g Sprague-Dawley rats were randomly divided into four groups of ten animals each and received 0 (control), 1 g/l, 2 g/l and 3 g/l caffeine in tap water for 3 days. Orthodontic appliances were ligated between the maxillary first molars and incisors on the 4th day of the study period. All rats were sacrificed after 2 weeks of treatment after which OTM was measured. Hematoxylin/eosin-stained sections of the molars were prepared and the mesial roots were examined for resorption-lacunae depth and osteoclast number. ANOVA was used for statistical analysis (P<0.05).

Results:

A significant decrease in OTM was observed only in the 2 g/l (P=0.043) and 3 g/l (P<0.01) caffeine-receiving rats compared to the control animals. Osteoclast counts and resorption-lacunae depths demonstrated significant differences between each of the caffeine groups and control rats (P<0.05). None of the variables showed significant differences between the caffeine groups (P>0.05).

Conclusion:

According to our findings, one of the effects of caffeine consumption during orthodontic treatment in rats was decreased root resorption. Additionally, concentrations of 2 g/l and 3 g/l inhibited OTM which seems to be due to its influence on osteoclast numbers.

Correlation between invasion mode and the histologic risk assessment model in oral squamous cell carcinoma

PURPOSE

The histologic risk assessment (HRA) model was proposed to assess clinical outcome of oral squamous cell carcinomas (SCCs), and its prognostic value has been confirmed in several studies, but its underlying molecular mechanisms has not been fully investigated. The objective of this study was to evaluate the association between immunohistochemical invasion mode of head and neck SCC and the HRA grading system.

METHODS

The HRA model consisting of risk scores (RSs), based on perineural invasion (PI), lymphocytic infiltration (LI), and worst pattern of invasion (WPOI), was used for grading 80 samples of head and neck SCC, followed by immunohistochemical staining with antibodies against E-cadherin, N-cadherin, and podoplanin. The two major invasion modes were considered as epithelial-mesenchymal-transition (EMT) and collective cell invasion (CCI) with profiles of E-cadherin^-/N-cadherin+/podoplanin^- and E-cadherin+/N-cadherin^-/podoplanin⁺, respectively. All other immunohistochemical profiles were classified as partial/incomplete EMT. Statistical analysis was performed by Kruskal-Wallis and Mann-Whitney U tests (P < 0.05).

RESULTS

Invasion pattern was significantly different among the three RSs (P = 0.01) and across the different scores of LI (P = 0.03) but not perineural invasion (PNI) (P = 0.07) and WPOI (P = 0.70).

CONCLUSIONS

Based on our results, it seems that there is a difference in EMT, CCI, and partial/incomplete EMT among the variables of the HRA model which might help clarify its functioning system.

A comparative study of syndecan-1 expression in different odontogenic tumors

BACKGROUND

Expression of various cellular/molecular factors change during the course of tumor formation from odontogenic tissues of the tooth germ. Evaluation of these factors can help provide a better perception of the tumorigenesis and biologic behavior of odontogenic tumors (OTs). Syndecan-1 is a heparan sulfate proteoglycan which has not been extensively investigated in these lesions. The objective of the present study was to assess the immunohistochemical expression of CD138 in adenomatoid odontogenic tumor (AOT), ameloblastic fibroma (AF) and odontogenic myxoma (OM) and to compare it with ameloblastoma and keratocystic odontogenic tumor (KCOT).

METHOD

A total of 58 OTs consisting of 7 AOTs, 5 OMs, 7 AFs, 29 KCOTs and 10 ameloblastomas were immunohistochemically stained with monoclonal antibody against syndecan-1 and the percentage and intensity of the immunostained cells was assessed. Kruskal-Wallis test followed by Bonferroni analysis was used for comparisons (P < 0.05).

RESULTS

Syndecan-1 was expressed in all samples except for OMs. Both percentage and intensity of syndecan-1 expression were statistically different among the studied OTs (P < 0.001). Pairwise comparisons showed significant difference only between OMs and each of the other tumors.

CONCLUSION

Syndecan-1 may be involved in the pathogenesis of AOT, AF, KCOT and ameloblastoma. However, considering the different behaviors of these tumors along with their similar expression of syndecan-1, it seems that its effect on clinical aggressiveness is limited. The significance of negative immunoexpression of this protein in OM requires further investigation.

Assessment of the Role of NO-cGMP Pathway in Orthodontic Tooth Movement Using PDE5 Inhibitors: An Animal Study

OBJECTIVES

Nitric oxide (NO) is a signaling molecule that mediates mechanical bone loading. Cyclic guanosine 3', 5' monophosphate (cGMP) is a NO-induced effector molecule. The aim of this study was to assess the effect of NO-cGMP pathway on orthodontic tooth movement (OTM) in rats by use of two phosphodiesterase 5 (PDE5) inhibitors namely sildenafil and tadalafil as chemical tools.

MATERIALS AND METHODS

Forty-five male Wistar rats were divided into three equal groups (n=15) based on the substance they received. The first group received daily injections of tadalafil; the second group received daily injections of sildenafil and the third group received daily injections of normal saline. The orthodontic appliances consisted of nickel-titanium closed-coil spring ligated between the maxillary right incisor and the first molar of the animals for 21 days. The amount of tooth movement was measured in all three groups at the end of this period. Histological analysis was performed to assess root resorption lacunae, osteoclast number and periodontal ligament (PDL) thickness.

RESULTS

All appliance-treated molars in the experimental and control groups showed evidence of tooth movement. The mean OTM was calculated to be 0.39±0.16, 0.32±0.16 and 0.26±0.16mm in tadalafil, sildenafil and control groups, respectively and there were no significant differences in OTM among the study groups (P>0.05). In the tadalafil group, significantly greater root resorption on the tension side was seen when compared with controls (P≤0.05).

CONCLUSIONS

Tadalafil and sildenafil PDE-5 inhibitors affecting the NO-cGMP pathway did not affect OTM in rats.

Nitrergic and opioidergic systems affect radiographic density ‎and histomorphometric indices in bile-duct-ligated cirrhotic rats

Metabolic bone disease is a major issue in chronic liver disease. Increased production of nitric oxide (NO) and elevation of endogenous opioids have been suggested to occur during cholestasis/cirrhosis. We aimed to investigate the involvement of nitrergic and opioidergic systems in bone loss after bile-duct-ligation (BDL) in rats using optical density (OD) evaluation and histomorphometric analysis. BDL- and sham-operated (SO) rats received injections of 3 mg/kg Nω-Nitro-L-arginine methyl-ester-hydrochloride (L-NAME) as an NO-synthase inhibitor, 10 mg/kg naltrexone (NTX) as an opioid-receptors antagonist or saline once daily for 28 days. Lateral cephalometric radiographs were taken on days 0 and 28 and histomorphometric and biochemical indices were measured. Plasma levels of total bilirubin and alkaline-phosphate were markedly increased in BDL compared with SO rats (p≤0.05). Among the studied variables, osteoclast number/mm trabecular surface showed significant increase in BDL animals compared to controls, which was significantly reduced following NO-synthase inhibition (p≤0.05). Similarly, cortical area slightly decreased in BDL animals in comparison to controls, whereas both L-NAME and NTX significantly increased this variable. Following BDL, optical density increased in the skulls of cirrhotic animals and showed a significant decrease after blocking opioid-receptors (p≤0.05). Inhibition of NO-synthase and/or opioid receptors caused significant changes in OD and histomorphometric parameters in BDL rats, both in favor of reducing bone loss. If confirmed by further studies, it seems that manipulation of these systems might be able to improve bone problems in subjects with cholestasis/cirrhosis.

Lymphangiogenesis and angiogenesis in oral cavity and lower lip squamous cell carcinoma

Introduction

Objective

Methods

Results

Conclusion

Status of p53 and p27(KIP1) in Iranian Patients With Oral Squamous Cell Carcinoma

Background:

Alterations in p53 and p27^KIP1 have been documented as important events in the carcinogenesis of various cancers, but their prognostic role in oral squamous cell carcinoma (OSCC) remains controversial.

Objectives:

The present investigation aimed to evaluate the clinicopathologic and prognostic significance of p53 and p27^KIP1 expression in a group of Iranian patients with OSCC.

Patients and Methods:

In this analytical cross-sectional study, medical records of patients with primary OSCC, diagnosed from 1994 to 2004 were reviewed and 28 subjects were selected based on the inclusion/exclusion criteria. Immunohistochemical staining using monoclonal antibodies against p53 and p27^KIP1 was performed on representative archival paraffin blocks. Demographic data along with information on p53 and p27^KIP1 expression, recurrence, and tumor grade was statistically analyzed using the Fischer exact test. Prognostic factors for overall survival were determined by Cox regression analysis (P < 0.05).

Results:

p53 and p27^KIP1 expression were found in 28.57% (8 positive versus 20 negative) and 67.85% (19 positive versus 9 negative) of OSCC cases, respectively. There was no significant association between these two proteins (P = 0.371), and neither of them showed a significant relationship with the studied clinicopathologic variables (P > 0.05). In survival analysis, only histopathologic differentiation (17 low and moderate, 11 poor) demonstrated a significant correlation with overall survival (P = 0.048).

Conclusions:

Despite the fact that abnormalities in p53 and p27^KIP1 may be involved in the development of OSCC, their clinical significance in the studied population seems limited. Further investigation on the combined p53/p27^KIP1 expression may be helpful in predicting the biologic behavior of this tumor.

Regenerative Effects of Three Types of Allografts on Rabbit Calvarium: An Animal Study

OBJECTIVES

The aim of this study was to histologically compare the regenerative properties of two allografts manufactured by two Iranian companies.

MATERIALS AND METHODS

In this study, four 8-mm defects were produced in the calvaria of 12 rabbits. In three defects, three types of allografts namely ITB, CenoBone and Grafton were placed and one defect served as control. Samples were prepared and histomorphometric evaluations were carried out after healing periods of four weeks (interval 1) and eight weeks (interval 2). Qualitative and quantities variables were compared and analyzed with SPSS software.

RESULTS

Mild inflammation was observed in 45% and 12.5% of the samples in the first and second intervals, respectively. Foreign body reaction was observed in only 5% of the samples. The quality of regenerated bone was immature, mixed and lamellar in 54.5%, 15.9% and 4.5% of the samples, respectively. The rate of allograft resorption was the highest and lowest in the CenoBone and Grafton samples, respectively. The mean amount of regenerated bone was higher in areas containing Grafton; however, the differences were not statistically significant.

CONCLUSION

Despite the differences in the numerical values of bone regeneration, there were no statistically significant differences in bone generation among the material groups, and allografts manufactured in Iran can be suitable alternatives to Grafton with the same good properties. Further studies are necessary to clarify the efficacy of these allografts.

Conventional versus Papanicolaou-stained cytobrush biopsy in the diagnosis of oral squamous cell carcinoma

AIMS

Squamous Cell Carcinoma (SCC) is the most frequent malignancy of the oral cavity which is known to have a high mortality rate. Early diagnosis of this cancer has a major role in the prevention of its progression and can help increase patient survival. Conventional biopsy is considered the gold standard for diagnosis of oral SCC. However oral brush biopsy is less invasive, quicker and easier than surgical method. The aim of this study was to assess the sensitivity of oral brush biopsy in patients with oral SCC.

METHODS

Thirty-five oral SCC subjects underwent. Cyrtobrush sampling followed by conventional biopsy and the latter was used as gold standard to determine the sensitivity of the brush biopsy technique. Papanicolaou and hematoxylin/eosin staining were used for cytopathologic and histopathologic assessments, respectively.

RESULTS

Only one patient was excluded due to inadequate sample material. A total of six of cytobrush specimens had the same diagnosis as their conventional biopsies (20.6% true positive), while 27 samples (79.4%) showed false negativity.

CONCLUSIONS

According to the results obtained in the present study, sampling with cytobrush followed by Papanicolaou staining may not be a good alternative for conventional biopsy in oral SCC cases.

Pantoprazole, a proton pump inhibitor, increases orthodontic tooth movement in rats

OBJECTIVES

Pantoprazole, is a proton pump inhibitor (PPI) prescribed for the treatment of upper gastrointestinal disorders, which in high doses has been suggested to decrease calcium absorption leading to hypocalcaemia and therefore osteoporosis. The aim of this study was to assess whether pantoprazol, could alter the rate of orthodontic tooth movement (OTM) in rats.

MATERIALS AND METHODS

A time course study was established using 72 rats which were divided into six groups of 12 samples each (four: vehicle; eight: pantoprazole + vehicle). Pantoprazole at a dose of 200 mg/kg suspended in carboxymethyl cellulose (0.25 percent) was administered by a gastric tube. The upper incisors and first molars were ligated by a 5 mm nickel-titanium closed-coil spring to deliver an initial force of 60 g. Animals were euthanized two weeks after orthodontic treatment followed by assessment of tooth movement and histomorphometric evaluation of the detached maxillae. Lateral skull radiographs were obtained once a week, starting from the first day to the 6(th) week of the study. OTM and bone density data were analyzed using independent sample t-test and repeated measures ANOVA.

RESULTS

No significant changes in OTM measurements and optical density were observed in vehicle-receiving animals during the study (P=0.994). OTM was significantly increased after six weeks pantoprazole therapy which continued until the 7(th) week of the experiment (P=0.007). Optical density significantly increased in the pantoprazole-treated rats after six weeks.

CONCLUSION

Long term PPI therapy at high doses could lead to osteoporosis and enhanced OTM.

Odontogenic Myxoma: a study based on biopsy material over a 40-year period

AIM

Odontogenic tumors, including odontogenic myxomas (OMs) are regarded as rare neoplasms in the human body. Nevertheless, they may be problematic for diagnosis and treatment planning due to possible variations between different races and countries. The aim of the current study was to present the clinicopathologic features of OM in an Iranian population over a 40-year period and compare them with those reported elsewhere.

MATERIALS AND METHODS

Clinical/demographic data and histologic slides of OMs and all lesions that could be considered in their differential diagnosis, reported from 1967-2008 were analyzed. Statistical analysis was performed using χ(2) and t-test and p < 0.05 was regarded significant.

RESULTS

Forty OMs were identified, of which 42.5% occurred in men (mean age, 27.4 years) and 57.5% in women (mean age, 28.2 years). Most tumors were observed in the posterior mandible. All cases possessed the classic World Health Organization histologic features; while 3, 15 and 6 cases showed epithelial rests, residual bone and conspicuous collagen bundles, respectively. Five patients were followed and none of their tumors recurred.

CONCLUSION

The clinicopathologic characteristics of the current Iranian population are similar to most other reports with a predilection for the posterior mandible, 3rd decade and female subjects; however, there were variations in microscopic features of the studied cases. Clinical significance: Clinical and histologic information on OM in different populations may be useful in clinical settings and treatment planning. Reporting more detailed histologic data can help clarify the biology of this tumor and aid in its histopathologic diagnosis. i