Immunohistochemical detection of Ki-67 is not associated with tumor-infiltrating macrophages and cyclooxygenase-2 in oral squamous cell carcinoma

Three-Dimensional Printing of an Apigenin-Loaded Mucoadhesive Film for Tailored Therapy to Oral Leukoplakia and the Chemopreventive Effect on a Rat Model of Oral Carcinogenesis

Oral leukoplakia, which presents as white lesions in the oral cavity, including on the tongue, is precancerous in nature. Conservative treatment is preferable, since surgical removal can markedly reduce the patient’s quality of life. In the present study, we focused on the flavonoid apigenin as a potential compound for preventing carcinogenesis, and an apigenin-loaded mucoadhesive oral film was prepared using a three-dimensional (3D) bioprinter (semi-solid extrusion-type 3D printer). Apigenin-loaded printer inks are composed of pharmaceutical excipients (HPMC, CARBOPOL, and Poloxamer), water, and ethanol to dissolve apigenin, and the appropriate viscosity of printer ink after adjusting the ratios allowed for the successful 3D printing of the film. After drying the 3D-printed object, the resulting film was characterized. The chemopreventive effect of the apigenin-loaded film was evaluated using an experimental rat model that had been exposed to 4-nitroquinoline 1-oxide (4NQO) to induce oral carcinogenesis. Treatment with the apigenin-loaded film showed a remarkable chemopreventive effect based on an analysis of the specimen by immunohistostaining. These results suggest that the apigenin-loaded mucoadhesive film may help prevent carcinogenesis. This successful preparation of apigenin-loaded films by a 3D printer provides useful information for automatically fabricating other tailored films (with individual doses and shapes) for patients with oral leukoplakia in a future clinical setting.

Evaluation of HPV and EBV in OSCC and the expression of p53, p16, E-cadherin, COX-2, MYC, and MLH1

OBJECTIVE

This study aimed to evaluate the presence of human papillomavirus (HPV) and Epstein-Barr virus (EBV) and the expression of p53, p16, E-cadherin, COX-2, MLH1, and MYC in oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

One hundred OSCC specimens were submitted to in situ hybridization for HPV and EBV, and immunohistochemistry for detection of the human proteins.

RESULTS

Thirty-one cases showed HPV in tumor tissue. EBV was not detected in any case investigated. The HPV(+) group demonstrated an increase of staining scores for nuclear p16 (p = .047), cytoplasmic MYC (p = .002), while a decrease for nuclear MLH1 (p = .048), suggesting that HPV may upregulate the expression of the first two proteins and down-regulate the latter.

CONCLUSION

Our findings reinforce the hypothesis of the HPV-related oral carcinogenesis involving the expression of p16 and MYC, and MLH1 suppression. Exclusively cytoplasmic stainings for p16, MLH1, and MYC were also associated with more advanced tumors. Finally, in view of the lack of studies correlating the HPV or EBV infection to the expression of oncoproteins, more researches assessing a broader panel of markers and employing different approaches are still necessary in order to understand the role of these viruses as well as the molecular mechanisms involved in the development and progression of oral carcinomas.

Role of Cyclooxygenase-2 in Head and Neck Tumorigenesis

The cyclooxygenase-2 (COX-2) is a potent enzyme that converts arachidonic acid to prostaglandins (PG), including PGE2, a key mediator of inflammation and angiogenesis. Importantly, COX-2 is activated in response to inflammatory stimuli, where it is also believed to promote the development and progression of head and neck cancers (HNC). COX-2 can mediate its protumorigenic effect through various mechanisms, such as inducing cell proliferation, inhibition of apoptosis, and suppressing the host’s immune response. Furthermore, COX-2 can induce the production of vascular endothelial growth factors, hence, promoting angiogenesis. Indeed, the ability of COX-2 inhibitors to selectively restrict the proliferation of tumor cells and mediating apoptosis provides promising therapeutic targets for cancer patients. Thus, in this comprehensive review, we summarized the reported differential expression patterns of COX-2 in different stages of head and neck carcinogenesis—from potentially premalignant lesions to invasive carcinomas. Furthermore, we examined the available meta-analysis evidence for COX-2 role in the carcinogenesis of HNC. Finally, further understanding of the biological processes of COX-2 and its role in orchestrating cell proliferation, apoptosis, and angiogenesis may give therapeutically beneficial insight to develop the management plan of HNC patients and improve their clinical outcomes.

Polarization and Distribution of Tumor-Associated Macrophages and COX-2 Expression in Basal Cell Carcinoma of the Ocular Adnexae

PURPOSE

Basal cell carcinoma (BCC) is a locally invasive skin tumor which can be subdivided into a circumscribed nodular and an invasive fibrosing subtype. There is increasing evidence that macrophages play an important role in interacting between tumor cells and their microenvironment, thereby affecting not only the invasive potential but also the patients' prognosis. Thus, we wanted to compare these two BCC variants with regard to tumor-related inflammation, COX-2 expression, distribution, and polarization of tumor-associated macrophages.

MATERIAL AND METHODS

30 BCCs (nodular: n = 15; fibrosing: n = 15) of the ocular adnexae were investigated by histopathology and immunohistochemistry. The grade of inflammation was evaluated on hematoxylin and eosin stains (score: 0-3). Immunohistochemical stains for CD68 (macrophages), Ki67 (proliferative activity), and COX-2 as well as immunofluorescence stains for CD68 and CD163 (to distinguish M1 and M2 macrophage subtypes) were performed. SPSS was used for statistical analysis.

RESULTS

Fibrosing BCCs were predominantly located on the lower lid, while nodular BCCs showed a broader distribution (p = 0.013). The fibrosing BCC subtype was associated with a higher degree of inflammation (p < 0.001) and revealed a higher COX-2 immunoreactivity than nodular BCC (p = 0.012). COX-2-positive cells were predominantly located on the infiltrating edge of the tumor. Macrophage polarization was balanced regarding M1 and M2 macrophage subtypes. There was no difference in macrophage number (p = 0.389) or polarization (p = 0.161) between nodular and fibrosing BCC.

CONCLUSIONS

The findings indicate that COX-2 represents a factor for invasion of BCC. Macrophage polarization did not play a major role for aggressive behavior. However, other inflammatory components than tumor-associated macrophages seem to be involved in tissue destruction and thereby an invading growth pattern since fibrosing BCC revealed a significantly more intense inflammatory reaction in the surrounding tissue.

Proliferative Index in Invasive Tumor Front of Oral Squamous Cell Carcinoma: A Potential Prognostic Indicator

AIM

The aim of the study was to evaluate the proliferative index (PI) at their invasive front of oral cancer and their association with Bryne's grades of oral squamous cell carcinoma (OSCC) and compare the PI with lymph node metastasis, site of involvement, and habits.

MATERIALS AND METHODS

The Ki-67 antigen expression was immunohistochemically evaluated in a total of 102 cases that included the histopathologically diagnosed archival specimens of OSCCs. They were subdivided by Bryne's histopathological grading into grade I (40 cases), grade II (32 cases), and grade III (30 cases). The nucleus with brown stain was considered positive. Cells were counted under 400× magnification. The proliferative activity thus determined was then expressed as a percentage of Ki-67 labeling index (Ki-67 LI) positive cells.

RESULTS

A stepwise increase in the mean Ki-67 LI was found from grade I to III squamous cell carcinoma, thus correlating with the histological grading. In addition, there was a higher PI seen in cases associated with metastatic lymph node, which concords with the higher biologic aggressiveness and poor prognosis of the lesion.

CONCLUSION

The present study shows a definitive correlation of Ki-67 antigen with the Bryne's histological grading, all the parameters of Bryne's grading for OSCC and lymph node status of the patient proving its association as an effective tool to grade the tumors and finally read the prognosis of the tumor.

CLINICAL SIGNIFICANCE

Cell proliferation is regarded as one of the most important biologic mechanisms in oncogenesis. The role of cell proliferation in tumor progression has been inferred in studies concerned with human cancer by comparing the PI of normal tissue, preneoplastic and neoplastic lesions. The Ki-67 antigen-labeled cells can prove to be an effective aid to grade the tumors. It might be possible to standardize and objectify tumor grading among pathology laboratories.

Ki-67 protein predicts survival in oral squamous carcinoma cells: an immunohistochemical study

The aim of this study was to identify the expression of Ki-67 and MCM3 in oral squamous cell carcinoma (OSCC) as well as to address the correlation with patient survival and clinical features. Samples were collected from 51 patients with OSCC who presented for follow-up. Immunohistochemical expression of Ki-67 and MCM3 in all groups was performed. The scoring system was previous published by Tsurutani in 2005. We used Kappa index to evaluate observers agreement degree. The associations between protein expression and clinical variables were examined for statistical significance using the chi-squared test. The overall survival rates were estimated by the Kaplan-Meier method and the relationship between protein expression and survival was compared using the log-rank test (p < 0.05). The overall survival time for a patient with positive immunostaining for Ki-67 is shorter than for a patient with negative immunostaining, (log-rank test, p = 0.00882). Patients with tumor size T3 and T4 showed a statistically significant relationship with Ki-67 immunoexpression (log-rank test, p = 0.0174). The relationship between Ki-67 expression and the relation between age, gender, smoking, tumor site, lymph node metastasis and disease stage was not significant. The examiners agreement degree by Kappa presented p value < 0.05. There was not a significant correlation when we evaluated MCM3 expression regarding clinical characteristics and survival rate. From these results, the present study suggests that positive Ki-67 expression found in OSCC patients may contribute to predict the survival in OSCC samples, as well as the relation between the protein and the tumor size.

Granular cell tumor mimicking a squamous cell carcinoma of the tongue: a case report

BACKGROUND

Granular cell tumor is a rare benign tumor that can present a pseudoepitheliomatous hyperplasia of the covering epithelium. This lesion is not encapsulated and can be characterized by a pseudo invasive growth pattern, represented by the tumoral cells that infiltrate between adjacent connective tissue elements. Diagnostic difficulties may arise because histopathological features of the pronounced pseudoepitheliomatous hyperplasia can be confused with a well-differentiated oral squamous cell carcinoma. The aim of this case report is to demonstrate the role of an immunohistochemical panel in the diagnosis of a granular cell tumor in the tongue with clinical and microscopic features resembling an oral squamous cell carcinoma.

CASE PRESENTATION

A 44-year-old white man with a history of heavy smoking and alcohol abuse presented an ulcerated nodular lesion in the dorsum of the tongue. The lesion was asymptomatic with fast growth. The clinical diagnosis was an oral squamous cell carcinoma. An incisional biopsy was performed and the ensuing histopathological analysis showed a pseudoepitheliomatous hyperplasia in the overlying epithelium mimicking the invasion of epithelial tumor cells into the connective tissue as in an oral squamous cell carcinoma. Immunohistochemical antibodies (S-100, vimentin, CD68, p53, Ki-67, E-cadherin, collagen IV and cytokeratin AE1/AE3) were used to characterize molecular aspects of the lesion. Strong staining of S-100 protein, CD68, vimentin, E-cadherin and low proliferative activity observed with Ki-67 expression confirmed the diagnosis of a granular cell tumor. The patient was submitted to surgical excision of the whole lesion. At a 12-month check-up, there was no evidence of recurrence.

CONCLUSION

This case report showed that the immunohistochemical profile was helpful in determining the clinical behavior of the tumor and establishing the final diagnosis with appropriate treatment.

Odontogenic epithelial proliferation is correlated with COX-2 expression in dentigerous cyst and ameloblastoma

Investigation of cyclooxygenase (COX)-2 in dentigerous cyst and ameloblastoma may help to improve understanding of the nature and behavior of odontogenic cysts and tumors, and in addition may eventually represent a definitive target for a pharmacological approach in the management of these lesions. The aim of this study was to evaluate COX-2 expression and its correlation with the proliferation of odontogenic epithelium in these lesions. Dentigerous cysts (n=16) and ameloblastomas (n=17) were evaluated. Detection of Ki-67 and COX-2 protein expression was conducted by immunohistochemistry. Data were statistically analyzed using Mann-Whitney U test and Spearman's rank correlation coefficient. No significant differences were found in the expression of Ki-67 and COX-2 between dentigerous cysts and ameloblastomas (P>0.05). A significant positive correlation (P=0.018) and highly significant positive correlation (P=0.004) were found between Ki-67 and COX-2 expression in the odontogenic epithelium of dentigerous cyst and ameloblastoma, respectively. COX-2 was expressed in the odontogenic epithelium of dentigerous cyst and ameloblastoma. It may contribute to local extension of these lesions by increasing the proliferation of their odontogenic epithelial cells.

Microlocalization of CD68+ tumor-associated macrophages in tumor stroma correlated with poor clinical outcomes in oral squamous cell carcinoma patients

CD68 has been widely used as a pan-macrophage marker for tumor-associated macrophages (TAM) which always involve in carcinogenesis. But the correlations between CD68(+) TAMs and prognosis of patients show to be inconsistent, which might due to lack of specific markers of TAMs. We here found that the microlocalization of CD68(+) TAMs also played a unique role in prognosis of patients with oral squamous cell carcinoma (OSCC). CD68(+) TAMs were identified in paraffin-embedded OSCC specimens (n = 91) by using immunohistochemistry. The number of CD68(+) TAMs was remarkably increased from adjacent none-neoplasia tissues (NT) to tumor nest (TN), but tumor stroma (TS) was infiltrated with highest frequency of CD68(+) TAMs (P < 0.0001). Unexpectedly, more CD68(+) TAMs in TS, but not NT or TN, were associated with high tumor grade (P = 0.033), lymph node metastasis (P = 0.034), and shorter 10-year overall survival time, disease free survival. Considering TAMs was derived from monocytes in peripheral blood, we assessed the relationship between leukocytes in peripheral blood and CD68(+) TAMs in OSCC and found that more CD68(+) TAMs in TS were accompanied with decreased monocytes and lymphocytes in peripheral blood (P < 0.05). Although Cox regression analysis revealed that CD68(+) TAMs in TS were not an independent prognostic factor for OSCC patients, we raised a possibility that the microlocalization of CD68(+) TAMs was an indispensable factor for the advance of OSCC.

Expression of CD163, interleukin-10, and interferon-gamma in oral squamous cell carcinoma: mutual relationships and prognostic implications

Tumor-associated macrophages (TAMs) and their associated inflammatory cytokines represent the major inflammatory component of the stroma of many tumors and can affect prognosis in the case of neoplasms. The objective of this study was to determine the prognostic significance of CD163(+) cells, interleukin-10 (IL-10), and interferon-gamma (IFN-γ) in oral lesions associated with oral squamous cell carcinoma (OSCC). The levels of CD163, IFN-γ, and IL-10 in the tissue samples of 240 patients with OSCC and 58 patients with other oral lesions were assessed by immunohistochemistry. Individuals with low IFN-γ levels, high IL-10 levels, and low CD163 levels were of special concern with respect to OSCC progression. We found that high levels of CD163, or a combination of low IFN-γ levels, high IL-10 levels, and low CD163 levels, were associated with poorer overall survival (OS). CD163(+) cells provide better predictive power for OS in comparison with traditional markers, such as clinical stage and lymph node metastasis. Therefore, CD163(+) cells may be effective prognostic predictors of OSCC. IL-10 may also indicate poor outcomes when IFN-γ secretion is low and the cells are CD163(-) .

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.

Tumor-Infiltrating Macrophage and Microvessel Density in Oral Squamous Cell Carcinoma

Tumor-associated macrophages (TAM) are the main cellular component in stroma of many tumors and participate in tumor angiogenesis. The aim of present study was to compare the microvascular density (MVD) and infiltrating macrophage density (IMD) in oral squamous cell carcinomas (OSCCs) with different histological grades. A histomorphometric analysis was performed after immunohistochemistry using antibodies such as von-Willebrand factor and CD68. A significant difference in MVD was found between well and moderately differentiated OSCCs (p<0.05). TAM were largely present in all studied tumors and the IMD was not different among OSCCs with different histological grades (p=0.381). Significant correlation between MVD and IMD was not observed (p=0.870). In conclusion, these results suggest that TAM and angiogenesis have an influence at different histological grades of OSCC. However, the lack of correlation between MVD and IMD could suggest that angiogenesis does not depend on the number of macrophages present in OSCC, but their predominant phenotype. Further studies involving distinct phenotypes of macrophages should be done to better understand the influence of TAM on the tumor angiogenesis.

Immunohistochemical comparative analysis of cell proliferation and angiogenic index in squamous cell carcinomas of the tongue between young and older patients

Oral squamous cell carcinoma (SCC) is a malignant epithelial tumor that is uncommon in individuals younger than 45 years. This study compared the cell proliferation and angiogenic index in SCCs of the tongue between young and older patients. Forty SCCs of the tongue, 20 diagnosed in young patients (≤ 40 y) and 20 diagnosed in older patients (>50 y) were evaluated by immunohistochemistry. Cell proliferation was evaluated using the Ki-67 labeling index (LI). The angiogenic index was determined by microvessel count (MVC) using anti- von Willebrand factor antibody. The mean Ki-67 LI in SCCs of the tongue was 43.8% (range, 26.0% to 72.4%) in young patients and 42.5% (range, 9.0% to 59.4%) in older patients (P=0.968). No significant difference in the Ki-67 LI was observed in relation to clinical stage or histologic grade of malignancy in either group (P>0.05). The mean MVC in SCCs of the tongue was 24.3 (range, 8.6 to 51.6) in young patients and 25.6 (range, 5.4 to 42.4) in older patients (P=0.543). There was no significant difference in MVC in relation to clinical stage or histologic grade of malignancy in either group (P>0.05). In addition, no significant correlation was observed between the Ki-67 LI and the angiogenic index (P>0.05). The results of this study suggest that the more aggressive biological behavior of SCC of the tongue in young patients may not be related to a higher cell proliferation rate or a higher angiogenic index.