Immunohistochemical detection of laminin-1 and Ki-67 in radicular cysts and keratocystic odontogenic tumors

CD34 and Ki-67 Immunoexpression in Periapical Granulomas: Implications for Angiogenesis and Cellular Proliferation

BACKGROUND/OBJECTIVES

The main mechanism of the formation of granulation tissue is the progression of an infection from the tooth to the periapical bone. At this level, the immune system tries to localize and annihilate the microorganism's injury. Ki-67 is a protein directly associated with the cell proliferation rate, while CD34 is a biomarker involved in angiogenesis, and studies suggest that they both have a positive correlation with the intensity of the local inflammatory infiltrate. This study will determine the immunoexpression of CD34 and Ki-67 in periapical granulomas and assess their impact on the growth and development of this tissue, as well as consider their roles in the proliferative process and aggressiveness of evolution.

METHODS

In the present study, 35 periapical granulomas obtained after a tooth extraction were included. The specimens were analyzed via histopathology and immunohistochemistry.

RESULTS

A positive reaction for the Ki-67 antibody was observed in 32 (86.5%) of the 35 periapical granuloma cases included in our study. We identified the overexpression of Ki-67 and CD34 and further calculated the Ki-67 index to evaluate and correlate the proliferation potential and angiogenesis with regard to the presence of an inflammatory infiltrate.

CONCLUSIONS

These findings suggest that the persistence of an inflammatory environment directly influences Ki-67 and CD34 expression, sustaining the proliferative capacity of cells and abnormal angiogenesis. This study is the first to evaluate the presence of the CD34+ and Ki-67+ proliferating vessels in periapical granulomas.

P63 and Ki-67 expression in radicular cyst

Objectives

The aim of the current study was to identify the expression of P63 and its relation to odontogenic epithelial cell proliferation, severity of the inflammatory infiltrate and size of radicular cysts (RCs).

Methods

In this retrospective cross-sectional study, 30 cases of paraffin-embedded RCs were randomly selected from the archive. P63 and Ki-67 expression was assessed by immunohistochemistry.

Results

Epithelial P63 expression was absent in four (13.3%), weak in 10 (33.3%), and moderate in 16 (53.3%) cases. In the connective tissue wall of RC, P63 expression was absent in two (6.7%) cases, weak in 24 (80.0%) cases, and moderate in four (13.3%) cases. Ki-67 was found to be weakly expressed in 12 (40.0%) cases, moderately expressed in 13 (43.3%), and strongly expressed in five (16.7%) cases. No correlation was found between Ki-67 expression in odontogenic epithelium and P63 expression in the odontogenic epithelium (rho = 0.110, p = .563) or fibrous capsule (rho = 0.160, p = .399). Nevertheless, we found a positive correlation between Ki-67 expression in the odontogenic epithelium and the size of the RC (rho = 0.450, p = .013). The inflammatory infiltrate was negatively correlated with P63 expression in the odontogenic epithelium (rho = -0.428, p = .018), and with the size of cysts (rho = -0.728, p < .001).

Conclusions

There is a high expression of P63 throughout the odontogenic epithelium and connective tissue capsule of the RC. P63 expression in the odontogenic epithelium is negatively correlated with the degree of the inflammatory infiltrate but not with epithelial cell proliferation or the size of the cyst.

Molecular pathogenicity of 1-nonadecene and L-lactic acid, unique metabolites in radicular cysts and periapical granulomas

Recently, 1-nonadecene and L-lactic acid were identified as unique metabolites in radicular cysts and periapical granuloma, respectively. However, the biological roles of these metabolites were unknown. Therefore, we aimed to investigate the inflammatory and mesenchymal-epithelial transition (MET) effects of 1-nonadecene, and the inflammatory and collagen precipitation effects of L-lactic acid on both periodontal ligament fibroblasts (PdLFs) and peripheral blood mononuclear cells (PBMCs). PdLFs and PBMCs were treated with 1-nonadecene and L-lactic acid. Cytokines' expression was measured using quantitative real-time polymerase chain reaction (qRT-PCR). E-cadherin, N-cadherin, and macrophage polarization markers were measured using flow cytometry. The collagen, matrix metalloproteinase (MMP)-1, and released cytokines were measured using collagen assay, western blot, and Luminex assay, respectively. In PdLFs, 1-nonadecene enhances inflammation through the upregulation of some inflammatory cytokines including IL-1β, IL-6, IL-12A, monocyte chemoattractant protein (MCP)-1, and platelet-derived growth factor (PDGF) α. 1-Nonadecene also induced MET through the upregulation of E-cadherin and the downregulation of N-cadherin in PdLFs. 1-Nonadecene polarized macrophages to a pro-inflammatory phenotype and suppressed their cytokines' release. L-lactic acid exerted a differential impact on the inflammation and proliferation markers. Intriguingly, L-lactic acid induced fibrosis-like effects by enhancing collagen synthesis, while inhibiting MMP-1 release in PdLFs. These results provide a deeper understanding of 1-nonadecene and L-lactic acid's roles in modulating the microenvironment of the periapical area. Consequently, further clinical investigation can be employed for target therapy.

Factors Influencing the Aggressive Behavior of Odontogenic Keratocyst: A Narrative Review

During odontogenesis, the dental lamina disintegrates, leaving behind the remnants. Odontogenic pathologies such as cysts and tumors can arise from these remnants. The odontogenic keratocyte (OKC) arises from dental lamina remnants. Among the cysts, the odontogenic keratocyst is the most controversial. There is convincing evidence that inflammation plays a significant role in the pathogenesis and expansion of OKCs. Several factors mediate the proliferative capacity of the epithelial lining. The presence of mast cells close to the epithelial lining, cystic pressure build-up by vascular endothelial growth factors (VEGFs), and other cytokines contribute to the cystic expansion. Fibroblast activation by inflammation in the connective tissue stroma and changes in the epithelial lining are responsible for the aggressive nature of OKC. The use of molecular methodologies gives more profound insights into the factors influencing the progression of the lesion and helps develop newer treatment modalities for OKC. This review describes the characteristics that determine the aggressive behavior of this unique cyst.

Histopathologic and immunohistochemical findings of odontogenic jaw cysts treated by decompression technique

Context

Odontogenic cysts are among the most common lesions to affect the oral and maxillofacial region. Cysts are capable of causing significant bony disfigurement, tooth displacement and pathological fractures. Several surgical approaches exist for the management of larger cysts of the jaws. These include enucleation, marsupialization and decompression.

Aims

1. Analysis of histopathologic findings in odontogenic cysts before and after decompression2. Analysis of Ki-67 expression in odontogenic jaw cysts before and after decompression.

Settings and Design

Decompression technique was used for the treatment of 10 cases of odontogenic cysts in the study. Incisional biopsies of cystic lining (pretreatment) and corresponding excisional biopsies (posttreatment) were received for histopathologic and immunohistochemical examination.

Subjects and Methods

Hematoxylin and eosin stain was used for histopathologic findings, and Ki-67 was used for immunohistochemical findings using antibody Ki-67 in fresh tissue samples.

Results

Overall, radicular cysts, dentigerous cysts, and sialo-odontogenic cyst contained fewer Ki-67 ⁺ cells than odontogenic keratocysts. The average scores were found to be 2.2 and 1 for before and after decompression, respectively. A statistically significant difference was observed between the two groups. The two-tailed P value was found to be <0.0001. The confidence interval was found to be 95%.

Conclusions

The proliferative activity evaluated by Ki-67 marker was greater in predecompression epithelial lining compared to postdecompression. Our study infers that proliferative rate of the cystic epithelial lining is significantly diminished after decompression.

Ki-67 expression as a diagnostic biomarker in odontogenic cysts and tumors: A systematic review and meta-analysis

Ki-67 is a marker of cell proliferation, used as an important diagnostic marker in the pathologic differentiation of various lesions. It is also relevant for developing targeted molecular therapies. We carried out a systematic review to assess the Ki-67 labeling index (LI) in odontogenic cysts and tumors. Databases were searched, including PubMed (MEDLINE), Scopus, CINHAL, PsycoInfo, the Cochrane Library, and Proquest. The meta-analysis was carried out based on the data of 608 lesions. When a 5% cut-off point was set, ki-67 LI of all benign odontogenic tumors dropped below this point. All the malignant tumors demonstrated an LI of over 15.3%; a significantly higher Ki-67 LI in malignant odontogenic lesions (17.59±2.80) was observed. Among benign tumors, the largest and the smallest Ki-67 LIs were seen in ameloblastoma (4.39±0.47) and adenomatoid odontogenic tumor (0.91±1.71). The mean values of Ki-67 LI in tumors and cysts were 4.23 (0.38) and 1.04 (0.07), respectively. Among odontogenic cysts, the highest Ki-67 LI was found in odontogenic keratocyst (OKC) (3.58±0.51), and the lowest in the radicular cyst (1.29±0.62%). Ki-67 LIs in all odontogenic cysts were <3%, except for OKC. This controversial lesion seems to have a profile more similar to a tumor, and a treatment plan similar to tumors might be suggested. We found that odontogenic lesions have diverse proliferative activities that help differentiate between various lesions and suggest therapeutic plans.

Proliferative and anti-apoptotic indices of unicystic ameloblastoma, odontogenic keratocyst, dentigerous cyst and radicular cyst

Objective:

The aim of this study is to compare the proliferative capacity and antiapoptotic capacity of unicystic ameloblastoma (UA), odontogenic keratocyst (OKC), dentigerous cyst (DC) and radicular cyst (RC) by assessing the Ki-67 labeling index (LI) and Bcl-2 LI, respectively.

Materials and Methods:

Formalin-fixed, paraffin-embedded tissue blocks of twenty-three histopathologically diagnosed UAs, 6 OKCs, 8 DCs and 10 RCs were selected from the archival specimens. Five micrometer thick sections of tissue blocks of the lesions were processed for immunohistochemical staining with Ki-67 and Bcl-2. The Ki-67 LI and Bcl-2 LI were determined for the cases with a positive reaction.

Results:

Ki-67 expression was seen in 6 (26.1%) cases of UA, 4 (66.7%) OKC, 1 (12.5%) DC and 1 (10.0%) RC. There was a statistically significant difference between the mean Ki-67 LI of UA and OKC (P = 0.024). Bcl-2 expression was seen in 16 (69.6%) UA, 5 (83.3%) OKC, 5 (62.5%) DC and 5 (50.0%) RC. The mean Bcl-2 LI of UA was significantly higher than that of DC (P = 0.048). Furthermore, cases of OKC had significantly higher mean Bcl-2 LI compared to DC (P = 0.026) and RC (P = 0.049).

Conclusion:

This study suggests that the Ki-67 LI may help in differentiating OKC from UA. The Bcl-2 LI may be useful in differentiating UA from DCs, and differentiating OKC from DC and RC.

Comparative immunoexpression of ICAM-1, TGF-β1 and ki-67 in periapical and residual cysts

Background

This study compared the immunohistochemical expression of ki-67, transforming growth factor beta 1 (TGF-β1) and intercellular adhesion molecule-1 (ICAM-1) in inflammatory periapical cysts and residual cysts.

Material and Methods

The study sample was composed by 25 periapical cysts and 25 residual cysts and immunohistochemical reactions were carried out using antibodies directed against ICAM-1, TGF-β1 and ki-67. Clinical, radiological, gross, histological and immunohistochemical data were tabulated for descriptive and comparative analysis using the SPSS software and differences were considered statistically significant when p<0.05%.

Results

There were no differences between the expression of ICAM-1 (p=0.239) and TGF-β1 (p=0.258) when comparing both groups. Ki-67 labeling index was higher in residual cysts compared to periapical cysts (p=0.017).

Conclusions

Results from the present study suggest that some specific inflammatory stimuli on residual cysts would modulate their mechanisms of etiopathogenesis, growing and repair.

Key words:Periapical cyst, radicular cyst, residual cyst, transforming growth factor beta 1 (TGF-β1), intercellular adhesion molecule 1 (ICAM-1), ki-67.

Study of the relationship between mononuclear inflammatory infiltrate and Ki-67 and basement membrane and extracellular matrix protein expression in radicular cysts

AIM

To evaluate the relationship between mononuclear inflammatory infiltrate and the expression of a proliferative immunomarker (Ki-67) as well as to evaluate basement membrane and extracellular matrix proteins (laminin and collagen type IV) in radicular cysts and dentigerous cysts (DC).

METHODOLOGY

Immunohistochemical analyses were performed in heavily inflamed radicular cysts (HIRC), slightly inflamed radicular cysts (SIRC) and DC (n = 20) using Ki-67 (Dako(®) , 1 : 50), anticollagen type IV (DBS(®) , 1 : 40) and antilaminin (DBS(®) , 1 : 20). The data were analysed using anova/Tukey's test (Ki-67) and Kruskal-Wallis/Dunn's test (collagen type IV and laminin) (P < 0.05).

RESULTS

The immunoexpression of Ki-67 was significantly greater in the SIRC group compared with the HIRC and DC (P = 0.0040). Likewise, the immunoexpression of collagen type IV in the basement membrane of the SIRC group was significantly more continuous (P = 0.0475) than in the HIRC group. DC had significantly less collagen type IV in extracellular matrix immunoexpression than HIRC and SIRC (P = 0.0246). Laminin was absent in the basement membrane in the SIRC and DC groups, and the extracellular matrix of the HIRC was weak and punctate.

CONCLUSION

The presence of inflammatory factors in the radicular cyst wall modified the expression of proliferation factors in the epithelial lining and the expression of collagen type IV and laminin in the basement membrane, but did not modify extracellular matrix behaviour in radicular cysts.

Keratocystic odontogenic tumor: a retrospective analysis of genetic, immunohistochemical and therapeutic features. Proposal of a multicenter clinical survey tool

OBJECTIVE

In 2005, the World Health Organization reclassified the parakeratinizing odontogenic keratocyst as a neoplasm. This article reviews the research leading to this reclassification, and validates a new survey tool that can be easily used to pool surgical and recurrence data from multiple offices.

STUDY DESIGN

All odontogenic lesions accessioned in the Iowa Surgical Oral Pathology Laboratory between 1949 and 2010 were identified from the database. A survey tool to assess treatment and follow-up was created. A total of 46 surgeons agreed to participate.

RESULTS

A total of 70 keratocystic odontogenic tumors (KOTs) had documented recurrences at follow-up intervals ranging from 6 months to 5 years. Primary tumors that recurred ranged in size as measured by greatest radiographic diameter from 0.7 to 6 cm.

CONCLUSIONS

This survey tool is recommended as standard allowing treatment of cases by multiple practitioners to be compared retrospectively or prospectively.

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.

Key words:Keratocystic odontogenic tumor, radicular cyst, angiogenesis, inflammation.

Ki-67 and MCM-2 in dental follicle and odontogenic cysts: the effects of inflammation on proliferative markers

The aim of this study was to investigate whether there is any association between inflammation and the expression of markers of cell cycle entry (Ki-67 and MCM-2) in dental follicle (DF) of asymptomatic impacted teeth and odontogenic cysts. The study consisted of 70 DFs and 20 odontogenic cysts (radicular cyst (RC), dentigerous cyst (DC) and keratocytic odontogenic tumor (KCOT) located at posterior mandibular region. Histological findings of inflammation for all specimen and mucous cell prosoplasia, squamous metaplasia, glandular epithelium for all DFs were stained with hematoxyline and eosin, periodic acid schiff, alcian blue, and mucin. Epithelial cell proliferation was determined by using immunohistochemical labeling for Ki-67 and MCM-2. The histologic examinations showed 16% mucous cell prosoplasia, 54% squamous metaplasia, 20% glandular epithelium, 37% inflammation. Inflammation was detected in all RCs and %62 in DF, %43 in DC and KCOT. Positive correlation was found between the inflammation of DF and odontogenic cysts (P < 0.01). The mean Ki-67 and MCM-2 expressions were found 9, 64 ± 5, 99 and 6, 34 ± 3, 81 in DF, 11, 85 ± 9, 01 and 13, 6 ± 9, 94 in odontogenic cysts, respectively. While the mean Ki-67 expressions were statistically significant in DF and KCOT (P < 0.01), MCM-2 were significant in RC and KCOT (P < 0.01). MCM-2 expresion in RCs were statistically significant than KCOT (P < 0.01). The results of this study indicated that the higher MCM-2 expressions in RC than the KCOT might be related to the inflammation and this protein might be more sensitive to inflammation.

Keratocystic odontogenic tumors: predictive factors of recurrence by Ki-67 and AgNOR labelling

PURPOSE

The purpose of the present study was to investigate the possible role of Ki-67 and argyrophilic nucleolar organizing regions (AgNOR) between the recurrent and nonrecurrent keratocystic odontogenic tumors (KCOTs). Another aim was to compare the correlation between these two markers.

MATERIALS AND METHODS

22 KCOTs were evaluated retrospectively. The actual proliferative activity of the KCOT was measured by Ki-67 labelling index and argyrophilic nucleolar organizing regions AgNOR count per nucleus.

RESULTS

Recurrence occurred in 3 patients (13.6%) during the follow-up period (mean follow-up, 37.8 months) The Ki-67 and AgNOR counts were significantly higher in the recurrent lesions comparing to the non-recurrent lesions. (p=0,045; p=0,049) The correlation between Ki-67 and AgNOR counts was found to be positive (r=0,853 p=0,0001).

CONCLUSION

Within the limit of the present study, it is thought that Ki-67 and AgNOR might be helpful as a prognostic marker for the recurrences of KCOTs. These markers reinforced the meaning of the new classification of the lesion as an odontogenic tumor. Enucleation with curettage or decompression following enucleation with curettage is a simple and appropriate surgical model for the treatment of KCOT despite the relative high recurrence rate. On the other hand, the conservative treatment can be chosen only if there is no coronoid invasion, no interruptive cortical lysis and no tissular invasion.

Neuronal markers are expressed in human gliomas and NSE knockdown sensitizes glioblastoma cells to radiotherapy and temozolomide

BACKGROUND

Expression of neuronal elements has been identified in various glial tumors, and glioblastomas (GBMs) with neuronal differentiation patterns have reportedly been associated with longer survival. However, the neuronal class III β-tubulin has been linked to increasing malignancy in astrocytomas. Thus, the significance of neuronal markers in gliomas is not established.

METHODS

The expressions of class III β-tubulin, neurofilament protein (NFP), microtubule-associated protein 2 (MAP2) and neuron-specific enolase (NSE) were investigated in five GBM cell lines and two GBM biopsies with immunocytochemistry and Western blot. Moreover, the expression levels were quantified by real-time qPCR under different culture conditions. Following NSE siRNA treatment we used Electric cell-substrate impedance sensing (ECIS) to monitor cell growth and migration and MTS assays to study viability after irradiation and temozolomide treatment. Finally, we quantitated NSE expression in a series of human glioma biopsies with immunohistochemistry using a morphometry software, and collected survival data for the corresponding patients. The biopsies were then grouped according to expression in two halves which were compared by survival analysis.

RESULTS

Immunocytochemistry and Western blotting showed that all markers except NFP were expressed both in GBM cell lines and biopsies. Notably, qPCR demonstrated that NSE was upregulated in cellular stress conditions, such as serum-starvation and hypoxia, while we found no uniform pattern for the other markers. NSE knockdown reduced the migration of glioma cells, sensitized them to hypoxia, radio- and chemotherapy. Furthermore, we found that GBM patients in the group with the highest NSE expression lived significantly shorter than patients in the low-expression group.

CONCLUSIONS

Neuronal markers are aberrantly expressed in human GBMs, and NSE is consistently upregulated in different cellular stress conditions. Knockdown of NSE reduces the migration of GBM cells and sensitizes them to hypoxia, radiotherapy and chemotherapy. In addition, GBM patients with high NSE expression had significantly shorter survival than patients with low NSE expression. Collectively, these data suggest a role for NSE in the adaption to cellular stress, such as during treatment.