Methylation Assessment of Two DKK2 and DKK4 Genes in Oral Squamous Cell Carcinoma Patients.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is one of the most important types of oral malignancies. DKK gene family members as well as DKK2/4 have critical roles in regulation of Wnt signaling as one of the main determining pathway in oral carcinogenesis. This study aimed to identify promoter methylation status of DKK2/4 genes to provide possible biomarkers for early detection and treatment of OSCC patients. METHODS: A case control study was performed on 31 fresh tissues obtained from oral cavity of patients affected by OSCC and 31 fresh corresponding tissues from normal healthy controls in Tehran and, between the years of 2016-2018. Purified DNA from tissue samples was subjected to bisulfite treatment and then methylation specific polymerase chain reaction (MSP-PCR) was carried out on treated DNA samples. RESULTS: DKK4 promoter was methylated in none of OSCC samples while it was methylated in 16.1% of healthy controls. 16.1% of OSCC samples were detected to be semimethylated and 22.6% of healthy normal samples were methylated for DKK2 promoter gene. Meaningful difference was found in DKK4 promoter methylation among OSCC patients and healthy controls. Significant correlation was found between DKK4 promoter methylation and tumor grade. The age of all enrolled samples was demonstrated to have strong effect on promoter methylation of studied genes. CONCLUSION: Hypomethylation of DKK2 and DKK4 genes in higher grades of OSCC samples may indicate the pivotal role of their expression in tumor cells invasion and progression through modulation of Wnt signaling pathway. Further study required to determine simultaneous expression of those genes and Wnt signaling elements at mRNA and protein levels.

Prognostic New Marker (Bone Morphogenetic Protein 7) in Squamous Cell Carcinoma.

AIM: Despite advances in the treatment of oral squamous cell carcinoma (OSCC), its prognosis is still poor. Therefore, it is important to identify the prognostic factors. The aim was to investigate the level of bone morphogenetic protein 7 (BMP7) in SCC of tongue and its relationship with some clinicopathologic parameters. MATERIALS AND METHODS: In this cross-sectional study, 128 patients with primary SCC of tongue were evaluated. Data were extracted and paraffin blocks were retrieved from the archives of Emam Khomeini Hospital, Tehran, and immunohistochemistry staining was done for the detection of marker. Data were analyzed using Statistical Package for the Social Sciences (SPSS) version 16 and through chi-square and logistic regression tests. RESULTS: The highest level of BMP7 expression was 54% in men (p = 0.044), 70% in the group aged under 45 years (p = 0.001), 68.2% in patients with lymph node metastasis (p < 0.001), and 100% in those with poorly differentiated tumors (p < 0.001). In multivariate analysis, the presence of lymph node metastasis and increased histopathological grade associated with 5.7 fold and 4.3 fold increase in the odds ratio (OR) of BMP7 expression respectively. CONCLUSION: Based on the results, there was a significant relationship between BMP7 expression and poor cellular differentiation and lymph node metastasis, so this marker could be a new prognostic marker in oral cancer. CLINICAL SIGNIFICANCE: This new marker could help clinicians to determine the prognosis of oral cancer, so it has an effect on optimal treatment.

Expression of podoplanin and TGF-beta in glandular odontogenic cyst and its comparison with developmental and inflammatory odontogenic cystic lesions.

BACKGROUND: The number of studies investigating the immunohistochemical characteristics of glandular odontogenic cysts (GOCs) is limited, due to its rarity. TGF-beta has been suggested to induce podoplanin expression in some lesions. We aimed to evaluate and compare podoplanin and TGF-beta expression in GOC and other odontogenic cystic lesions. METHODS: A total of 43 samples including five GOCs, 10 dentigerous cysts (DCs), eight unicystic ameloblastoma (UAs), and 20 radicular cysts (RCs) were selected and subjected to immunohistochemical staining using monoclonal antibodies against podoplanin and TGF-beta. Kruskal-Wallis test and Mann-Whitney U-test were used for statistical analysis along with Bonferroni for adjusting P-values (P < 0.05). RESULTS: Podoplanin immunoreactivity was observed in 80%, 70%, and 100% of DCs, RCs, and UAs, respectively, while none of the GOCs were positive for this marker (P = 0.004). Significant differences were only found in the GOC specimens. TGF-beta positivity occurred in the capsule and epithelium of all GOCs and DCs, while RCs and UAs demonstrated different expression percentages in the capsular and epithelial tissues. Epithelial TGF-beta showed significant differences among the studied lesions (P = 0.007) with the main difference found between DCs with RCs and DCs with UAs. CONCLUSIONS: Lack of podoplanin expression might be involved in the characteristic histologic and behavioral features of GOC, which seems to be unrelated to TGF-beta expression.

An analysis of biopsy-proven tongue lesions among 8,105 dental outpatients.

AIM: The aim of the present study was to analyze data on the characteristics of tongue lesions in dental patients seeking care at the Oral Pathology Service of Tehran University of Medical Sciences, from 1985-2010. MATERIALS AND METHODS: Demographic data and histopathologic diagnoses were recorded for all lesions that were documented as occurring on the tongue according to the patient records in our department. Statistical analysis included chi-square, t-, and Fisher's exact tests. A 95% confidence interval (CI) was calculated, and p < 0.05 was considered significant. RESULTS: Tongue lesions constituted 6.3% of all received specimens which included 46 different defects. The most common lesions were lichen planus (LP), irritation fibroma (IF), squamous cell carcinoma (SCC) and pemphigus vulgaris (PV). Tongue lesions were significantly more common in women compared to men (CI = 0.65-0.94, p = 0.02). Mean age (47 years) did not differ between male and female subjects (CI = -2.49 - 3.93, p = 0.06). The dorsal surface followed by the lateral aspect was the most common site for tongue lesions. CONCLUSION: It seems that dental practitioners should be perceptive of LP, IF, SCC and PV, when examining the tongue. Histopathologic analysis is essential for achieving final diagnosis in a considerable number of lesions that commonly occur on this organ. Clinical significance: Access to demographic/prevalence data in different populations may be useful in clinical settings and could be complimented by histopathologic diagnosis in most instances. The present findings can be compared with those obtained from other epidemiologic studies in this field resulting in valuable data which may be used in several types of investigations. .

Exploring the concept of "inflammatory angiogenesis" in keratocystic odontogenic tumor.

OBJECTIVE: The aim of the present study was to investigate the role of inflammation in angiogenesis of keratocystic odontogenic tumor (KCOT). STUDY DESIGN: Twenty inflamed and 20 non-inflamed KCOTs were selected based on quantitative scoring of inflammation which was also applied on 20 radicular cysts. Microvessel density was assessed in all samples using CD34 antibody and angiogenesis was compared between the three groups. Statistical analysis was performed using one-way analysis of variance followed by post-hoc Scheffe test and P values less than 0.05 were considered significant. RESULTS: A statistically significant difference in angiogenesis was found between radicular cysts and both inflamed and non-inflamed KCOTs (P < 0.001), but not between inflamed and non-inflamed KCOTs (P =0.347). CONCLUSION: Based on the results obtained in the present study, it seems that the effect of inflammation on angiogenesis in KCOT is minimal. However further investigation using other methods of evaluation is suggested to fully clarify the role of "inflammatory angiogenesis" in this neoplasm.

Suitability/unsuitability of cell proliferation as an indicator of malignant potential in oral lichen planus: an immunohistochemical study.

BACKGROUND: Oral lichen planus (OLP) is categorized as premalignant lesion although its malignant potential is a matter of controversy. The objective of this study was to investigate Ki67 expression in OLP, oral epithelial dysplasia and oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: Expression of Ki67 was evaluated through immunohistochemistry (IHC) in groups of A (17 cases of epithelial hyperplasia), B (16 cases of OLP), C1 (10 cases of mild epithelial dysplasia), C2 (10 cases of severe epithelial dysplasia), D1 (10 cases of well-differentiated OSCC), and D2 (10 cases of poorly-differentiated OSCC). RESULTS: There was a significant difference in Ki67 expression based on quantitative analysis among the six studied groups as well as group B compared bilaterally with groups C2, D1 and D2 (p< 0.0001). However, there was no significant difference between groups B and C1 or between groups D1 and D2 (p> 0.05). CONCLUSIONS: Based on the results of the present study it may not be possible to definitely consider malignant transformation potential for OLP. However, expression of Ki67 was significantly higher in OLP than that of epithelial hyperplasia with no significant difference from that of mild epithelial dysplasia. This should be considered by clinicians to carefully and regularly follow up OLP lesions to detect potential subtle changes at an early stage.

Reactive lesions of the oral cavity: A retrospective study on 2068 cases.

BACKGROUND: Reactive lesions of the oral cavity are non-neoplastic proliferations with very similar clinical appearance to benign neoplastic proliferation. This similarity is troublesome in the differential diagnosis. The aim of this study was to determine the frequency and distribution of oral cavity reactive lesions. MATERIALS AND METHODS: The study was a retrospective archive review. The medical records of 2068 patients with histopathologic diagnosis of oral cavity reactive lesions were studied. The patients' clinical data were registered and evaluated retrospectively. The obtained frequency of patients' age, gender, and anatomic location were analyzed. Descriptive statistics were used for evaluating the registered data. RESULTS: Peripheral giant cell granuloma was the most prevalent lesion (n=623, 30.12%). This was followed by pyogenic granuloma (n=365, 17.65%), epulis fissuratum (n=327, 15.81%), irritation fibroma (n=288, 13.93%), cemento-ossifying fibroma (n=277, 13.40%), inflammatory fibrous hyperplasia (n=177, 8.56%), and inflammatory papillary hyperplasia (n=11, 0.53%). The age ranged from 2 to 85 years, with a mean of 39.56 years. The lesions were more common in males (n=1219, 58.95%) than in females (n=849, 41.05%). Attached gingiva with 1331 (64.36%) cases was the most frequent place of reactive lesions. CONCLUSION: Peripheral giant cell granuloma was the most prevalent reactive lesion of the oral cavity. The reactive lesions were more common in males, gingival, and the third decade. Some differences have been found between the findings of the present study and previous reports.

Gene polymorphism of interleukin-1 alpha and beta in keratocystic odontogenic tumors.

AIM AND BACKGROUND: Odontogenic keratocysts have a different growth mechanism and biologic behavior in comparison with more common dentigerous and radicular cysts. It was reclassified as keratocystic odontogenic tumor (KCOT). The proliferative activity of the epithelial cells of KCOT has a close relationship with tissue levels of interleukin-1 (IL-1). Moreover, IL-1 increases the expression of several matrix metalloproteinases in the fibroblasts of adjacent stroma and activates the osteoclastogenesis process. So it plays an important role in the activity, spread, and local aggressiveness of this tumor. Therefore, it seems that the gene polymorphism of the cytokines of the IL-1 family is influential in the pathogenesis of KCOT and the patients' susceptibility to disease. METHOD: A total of 38 blood samples of patients suffering from KCOT and 150 blood samples of healthy patients were assessed using PCR-SSP. The blood samples were assessed for the following polymorphisms: interleukin-1 alpha (-889) and interleukin-1 beta (-511). Following up the patients, we found six recurrent and one syndromic cases. FINDINGS: By comparing the case and control groups, we observed the significant dominance of allele T over C, and genotype TT over CC and CT in IL-1α, although no significant difference was seen in the allele frequency and genotypes regarding IL-1ß. CONCLUSION: The function of IL-1α has a significant relationship with KCOT. Its effective genotype associated with pathogenesis, growth, local invasion, and recurrence is TT.

The effect of platelet-rich plasma on healing of palatal donor site following connective tissue harvesting: a pilot study in dogs.

BACKGROUND: Peri-implant plastic surgery includes soft tissue enhancement by connective tissue grafting. The palatal donor site provides peri-implant keratinized mucosa and soft tissue height. Platelet-rich plasma (PRP) contains growth factors that may enhance early healing. PURPOSE: The present animal study investigated the effect of PRP on wound healing of palatal donor site after connective tissue harvesting. MATERIALS AND METHODS: In 12 mongrel dogs, bilateral palatal connective tissues of 10 × 15 mm were harvested. At test site, PRP was applied into the wound, and the contralateral site served as control. The healing was evaluated clinically and histologically at 1 week, 2 weeks, and 4 weeks after surgeries. Exact binomial probability and Wilcoxon signed-rank test were used to compare the clinical and histologic measurements. RESULTS: No statistically significant differences between PRP and control sites were measured with regard to clinical healing (p = 1.000) and histologic variables, including inflammatory cells (p = .750), collagen fibers (p = .375), and granulation tissue (p = .500) at any time interval. CONCLUSION: The addition of PRP to palatal mucosal wound sites did not accelerate wound healing.

Assessment of cellular proliferation in oral verrucous carcinoma and well-differentiated oral squamous cell carcinoma using Ki67: a non-reliable factor for differential diagnosis?

BACKGROUND: Non-invasive oral verrucous carcinoma (OVC) and invasive well-differentiated oral squamous cell carcinoma (OSCC) have similar histopathologic findings but different biological behavior. These two malignancies must be correctly differentiated by pathologists. The aim of this study was to determine immunohistochemical (IHC) expression of Ki67 in OVC and well-differentiated OSCC. METHODS: Expression of Ki67 was evaluated by IHC in 15 cases of epithelial hyperplasia with no dysplasia (A group), 15 cases of OVC (B group), 12 cases of microinvasive OSCC(C group) and 15 cases of well-differentiated OSCC (D group). RESULTS: There was a significant difference in Ki67 expression based on pattern distribution of immunostaining positive cells, with quantitative and semi-quantitative analyses, among the four groups ; also, between A group and each of the other three groups (P=0.0001). But there was no significant difference between B and C, C and D, and B and D groups (P>0.05). CONCLUSIONS: The three evaluation methods of Ki67 expression showed Ki67 (Mib-1) is not a good immunohistochemical marker to assess invasion status and differentiate OVC from well-differentiated OSCC; also, it cannot be used as a diagnostic tool to distinguish between variants of OSCC with similar grade.

Synovial sarcoma of the mandible.

Synovial sarcoma (SS) is a relatively common soft tissue tumor but only 6%-7% of cases are diagnosed in the head and neck region. It typically occurs in young adults and is slightly more common in males. The most common sites in the head and neck region are hypopharynx and parapharyngeal spaces. However, SS can also occur in tonsils, tongue, and orofacial soft tissues. It is not difficult to diagnose SS microscopically with its classic biphasic appearance, but the diagnosis of monophasic forms is more challenging especially in unusual locations. In this article, we report a rare case of monophasic SS of the mandible. The clinical, histopathological, and immunohistochemical features are discussed and compared with previously reported cases in the literature. To our knowledge, only six primary involvements have been reported in the jaws. Therefore, our case represents the seventh reported case of SS in the area.

Immunohistochemical evaluation of type IV collagen and laminin-332 γ2 chain expression in well-differentiated oral squamous cell carcinoma and oral verrucous carcinoma: a new recommended cut-off.

BACKGROUND: Invasion and metastasis are two characteristics of malignant tumors, which perform by proteolytic destruction of the components of basement membrane (BM) and cell migration. The aim of this study was to evaluate the immunohistochemical (IHC) assessment of type IV collagen and laminin-332 γ2 (Ln-332 γ2) chain expression in well-differentiated oral squamous cell carcinoma (OSCC) and oral verrucous carcinoma (OVC), because these two lesions have same histopathologic findings whereas they have different biological behaviors. METHODS: Destruction of BM and cell migration were evaluated by IHC in 15 cases of epithelial hyperplasia with no dysplasia (A group), 15 cases of OVC (B group) and 15 cases of well-differentiated OSCC (C group). RESULTS: There was a significant difference in type IV collagen immunohistochemical staining between three groups, but there were no significant differences between B and C groups. Expression of Ln-332 γ2 chain was not detected in A group. Ln-332 γ2 chain labeling index had significantly difference between B and C groups. The number of Ln-332 γ2 chain immunostaining positive cells was less than 5% in B group and over than 5% in C group which there were significantly differences between these two groups. CONCLUSIONS: Isolated immunohistochemical study of type IV collagen does not clearly define that a lesion is invasive or non-invasive and evaluation of Ln-332 γ2 chain expression (cut-off 5%) may be useful as a marker for description of biological differences and diagnosis of OVC from well-differentiated OSCC, especially in doubtful cases.

Peripheral and central giant cell granulomas of the jaws: a demographic study.

OBJECTIVE: This study aimed to assess the demographic characteristics of peripheral giant cell granulomas (PGCGs) and central giant cell granulomas (CGCGs) in patients treated at our centers. STUDY DESIGN: This 12-year retrospective study was based on existing data. Files of patients from 1993-2004 with a definite diagnosis of PGCGs and CGCGs from the oral pathology departments of our universities were assessed. Information regarding age distribution, gender, the jaw involved, the presenting area of the lesion, surgical treatment, and recurrence was documented. RESULTS: During the study period, 204 patients with CGCGs were treated. The patients with CGCGs varied in age from 5 to 72 years, and the mean age patients was 23.72 years. Among these, 127 cases (62.87%) occurred in the second and third decades of life. One hundred thirty cases (63.75%) occurred in females and 74 (36.25%) in males. Ninety cases (44.1%) presented in posterior parts of the jaws. One hundred forty-four cases (70.58%) appeared in the mandible. Peripheral GCGs presented in 575 patients, who varied in age from 2 to 85 years with a mean age of 31.02 years. Among these, 297 cases (51.65%) occurred in females and 278 (48.34%) in males. Four hundred sixty-seven cases (81.2%) occurred in the first five decades of life, and 352 cases (61.21%) appeared in the mandible. CONCLUSIONS: Giant cell granulomas comprised 9.29% of oral lesions. Peripheral GCG lesions occurred more than 2 times more frequently than CGCGs. Central GCGs occurred about 2 times more frequently in females, whereas PGCGs had an equal prevalence in both genders (P < .05). The mean age for patients with CGCGs was less than patients with PGCGs (P < .05). Central GCGs involved the mandible approximately 2 times more frequently than the maxilla (P < .05). However, when presenting in the maxilla, CGCGs most frequently presented in the area anterior to the canines (P < .05). Peripheral GCGs involved the mandible approximately 1.5 times more frequently than the maxilla (P < .05). Thorough curettage was the main treatment modality used. There were 9 cases (4.41%) of recurrence of CGCGs and 8 cases (1.39%) of recurrence of PGCGs documented during the follow-up period (ranging from 1-12 years).

Expression of p21WAF in salivary gland mucoepidermoid carcinoma and its relation to histologic grade.

The biologic behavior and factors influencing the development of salivary gland mucoepidermoid carcinoma are not fully understood. Alteration of the cyclin-dependant kinase inhibitor p21(WAF) could cause uncontrolled proliferation leading to cancer. Thirty-five mucoepidermoid carcinomas were graded and immunohistochemically stained for p21(WAF). The percentage of positive tumor cells was determined using an eyepiece graticule and a computer-assisted image analyzer, which revealed 8.6% and 22.9% of the cases to be positive for p21(WAF), respectively. A statistically significant correlation was not observed between p21(WAF) and grading. Considering the absence of p21(WAF) expression in most mucoepidermoid carcinomas, it appears that the inhibitory effect of p21(WAF) on cell growth is removed in most cases. Given the lack of correlation with tumor grade, it is possible that the impact of p21(WAF) is in the earlier stages of tumorigenesis. A p53-independent pathway of p21(WAF) induction may exist for the small proportion of tumors that showed positivity.