Expression of p53 in leukoplakia and squamous cell carcinoma of the oral mucosa: correlation with expression of Ki67

p53, Cytokeratin 19 Expression in Oral Squamous Cell Carcinoma and Correlation with Histopathologic Grading: An Immunohistochemical Study

The purpose of this study was to examine the immunohistochemical expression of p53 and cytokeratin 19 (CK19) in normal oral mucosa (NOM) and oral squamous cell carcinoma (OSCC) and their association with histopathological differentiation grade. The secondary goal was to see if there was any correlation between p53 and CK19 expression in NOM and OSCC. A hospital-based retrospective analysis was conducted in which 40 NOM and 45 OSCC samples were acquired from archives and stained with mouse monoclonal antibodies p53 and CK19. For both the NOM and OSCC groups, the proportion of positively stained cells, staining intensity, and staining index were calculated. p53 immunoexpression revealed that 85% of positively stained cells in the NOM basal layer had a low staining index (mean ± SD 1.87 ± 0.34), whereas 66.7% of positively stained cells in the OSCC had a high staining index (mean ± SD 5.63 ± 3.02). When NOM and OSCC were compared, there was a statistically significant difference in staining intensity. However, despite a linear increase in the percentage of positive cells from well to poorly differentiated, the comparison between histopathological grades was non-significant. CK19 exhibited 18.5% positively stained cells in the NOM basal layer with a low staining index (mean ± SD 1.57 ± 0.53), whereas OSCC samples showed 4.44% immunopositivity with a high staining index. p53 is a marker of oral carcinogenesis independent of histological grade and CK19 expression. Further, CK19 is a marker of dysfunctional epithelial differentiation but lacks sensitivity and specificity; however, it demands further multicentric studies with a large sample size to draw definitive conclusions.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-023-04092-7.

Emerging Role of Decoy Receptor-2 as a Cancer Risk Predictor in Oral Potentially Malignant Disorders

The aim of this study was to evaluate the expression of the senescence markers, Decoy Receptor 2 (DcR2) and Differentiated Embryo-Chondrocyte expressed gen 1 (DEC1), in oral potentially malignant disorders (OPMDs) to ascertain their possible association with oral cancer risk. The immunohistochemical analysis of DcR2 and DEC1 expression (along with p16 and Ki67 expression) was carried out in 60 patients with clinically diagnosed oral leukoplakia. Fifteen cases (25%) subsequently developed an invasive carcinoma. Correlations between protein marker expression, histological grade and oral cancer risk were assessed. DcR2, DEC1 and Ki67 protein expressions were found to correlate significantly with increased oral cancer risk, and also with an increased grade of dysplasia. Multivariate analysis demonstrated that DcR2 and Ki67 expression are independent predictors of oral cancer development. Our results evidence for the first time the potential of DcR2 as an early biomarker to assess oral cancer risk in patients with oral leukoplakia (HR = 59.7, p = 0.015), showing a superior predictive value to histology (HR = 4.225, p = 0.08). These findings reveal that the increased expression of DcR2 and DEC1 occurred frequently in OPMDs. In addition, DcR2 expression emerges as a powerful biomarker for oral cancer risk assessment in patients with oral leukoplakia.

Correlation of Soluble CD44 Expression in Saliva and CD44 Protein in Oral Leukoplakia Tissues

The aim of this study was to determine whether and how pan-CD44 protein expression in leukoplakia tissues correlates with positive SolCD44 test presence and their role in oral leukoplakia. SolCD44 and total protein expression in saliva were determined using an OncAlert^® Oral Cancer Rapid test. Comparison of paired associations of total protein, SolCD44, mean number of CD44 expressed epithelial layers in leukoplakia tissue, and macrophages below the basement membrane between control group and patients with leukoplakia showed statistically significant results (p < 0.0001). It is shown that the total protein indicates low or elevated risk of possible malignant transformation processes in leukoplakia. Statistically significant differences between higher total protein level and clinical forms of oral leukoplakia (p < 0.0001), as well as CD44-labeled epithelial cell layer decrease (p < 0.0001), were found. This possibly points to the onset of the stemness loss in leukoplakia tissue. CD9 antigen expression in the exosomes of the oral epithelium explained the intercellular flow of SolCD44 and other fluids in the leukoplakia area. We conclude that the OncAlert^® Oral Cancer Rapid test is a valuable screening method in daily clinical practice, in terms of complementing clinical diagnostics methods and to assess the potential for early malignancy.

Importance of Ki-67 Labeling in Oral Leukoplakia with Features of Dysplasia and Carcinomatous Transformation: An Observational Study over 4 Years

Background  Early detection of dysplastic changes within oral potentially malignant disorders is the mainstay to prevent oral cancer. Ki-67 is one of the most useful antigens in this purpose.

Aims  The study aims were to recognize and mutually compare the proliferative status of idiopathic oral leukoplakia (OL) patches, which presented through different forms of dysplasia and carcinoma.

Settings and Design  In 4 years of observation, cumulatively 140 OL lesions were included for examination. The wholesome Ki-67 labeling scores in each of the subgroups were calculated.

Subjects and Methods  The World Health Organization recommended histopathological classification was used to categorize the dysplastic and malignant lesions. Paraffin-embedded tissue sections were processed for Ki-67 immunostaining. The labeling indices (LIs) were quantified semiquantitatively at the site of maximal reactive cells on tissue sections.

Statistical Analysis  The statistical comparison was performed by means of the SPSS software (Version 16.0 SPSS Inc.). A p- value < 0.05 was considered as the benchmark for statistical significance.

Results  A steady and significant increment in Ki-67 expression was discovered from dysplastic to malignant OL patches compared with normal mucosa. The labeling differences were significant between normal mucosa and mild dysplasia, as well as between mild, moderate, and severe dysplasia. However, the expression did not differ significantly with the severity of oral cancers.

Conclusions  Ki-67 is a useful molecular marker of carcinogenesis in OL. It also serves worthwhile in separating marginally dysplastic lesions, such as mild dysplasia or verrucous carcinoma from their benign epigones.

BMI-1 expression increases in oral leukoplakias and correlates with cell proliferation

Oral leukoplakia (OL) is a white lesion of an indeterminate risk not related to any excluded (other) known diseases or disorders that carry no increased risk for cancer. Many biological markers have been used in an attempt to predict malignant transformation; however, no reliable markers have been established so far.

Evaluation of Ki-67 Expression in Oral Submucous Fibrosis and Its Correlation with Clinical and Histopathological Features

Objectives:

Oral submucous fibrosis (OSMF) is a potentially malignant disorder. Although it shows atrophic epithelium, it has a high proliferative capacity. Therefore, this study correlates the Ki-67. (The name “ki” is derived from the city of origin [Kiel, Germany] expression with functional grading and epithelial thickness in OSMF).

Methods:

The study group comprised of thirty patients of OSMF, divided randomly into Group A, Group B, Group C, and Group D as per mouth opening (functional staging). Five participants without OSMF formed the negative control group. The positive control group comprised of five patients of diagnosed cases of squamous cell carcinoma. All the sections of biopsy were subjected for hematoxylin and eosin and immunohistochemistry staining and observed for expression of Ki-67. Epithelial thickness was evaluated using image analysis software of Leica research microscope. Images were analyzed by three independent observers who were blindfolded. All the findings were tabulated and statistically analyzed.

Results:

In the present study, as the functional staging increased, the Ki-67 expression also increased. Ki-67 expression was highest in severe functional staging/severely decreased mouth opening (100.78) and is least in mild functional staging/mild decreased mouth opening (10.39). However, there was no significant correlation between epithelial thickness and functional staging/mouth opening (P > 0.05).

Conclusion:

A decrease in functional staging (mouth opening) showed a greater expression of Ki-67, and there was no significant correlation between functional staging and epithelial thickness.

Ki67, CD105 and α-smooth muscle actin expression in disease progression model of oral submucous fibrosis

AIM

The aim of this study was to investigate the expression of Ki67, CD105 and α-smooth muscle actin (α-SMA) expression in oral submucous fibrosis (OSF) and oral squamous cell carcinoma in the background of OSF (OSCC-SMF).

METHODS

The study was carried out on paraffin-embedded tissues of 30 normal oral mucosa (NOM), 50 OSF cases and 105 OSCC-SMF. The immunohistochemistry was carried out to evaluate the expression of Ki67, CD105 and α-SMA antigen.

RESULTS

Ki67 labelling index (LI), CD105 and α-SMA expression showed increasing trend from NOM, low-risk epithelial dysplasia (LRED), high-risk epithelial dysplasia (HRED), well-differentiated squamous cell carcinoma (WDSCC), moderately differentiated squamous cell carcinoma to poorly differentiated squamous cell carcinoma. However, there was no significant difference of α-SMA expression between HRED and WDSCC. In OSCC-SMF, Ki67 LI, CD105 and α-SMA were significantly higher in advanced clinical TNM stage, metastasis and less than 3 years patient survival as compared with early clinical TNM stage, non-metastasis and 3 years or more patient survival.

CONCLUSION

Ki67 LI, α-SMA and CD105 expression alone or together correspond with the disease progression model of SMF. Hence, expression of these markers can be used as a predictive marker of clinical outcome of OSCC-SMF.

p53 Expression in Leukoplakia and Carcinoma of the Tongue

There is growing interest in assessing multistep carcinogenesis and predicting its course using different molecular markers. TP53 is a tumor suppressor gene and appears to be one of the molecular targets of tobacco-related carcinogens in oral cancer. The present study evaluated the role of p53 expression in patients with leukoplakia and carcinoma of the tongue. p53 expression was studied by immunohistochemistry. All patients with leukoplakia of the tongue were male tobacco users. Nuclear staining of p53 was observed in 79% of those patients. Fifty percent, 25% and 4% of the patients expressed 1+, 2+ and 3+ nuclear staining, respectively. When leukoplakia patients were graded according to histopathology, 67% had hyperplasia and 33% had dysplasia. Nuclear p53 accumulation was 88% in hyperplasia and 62% in dysplasia. In patients with tongue cancer, nuclear accumulation of p53 was seen in only 19% of the tumors, with a staining intensity of 1+ in 13%, 2+ in 2% and 3+ in 4% of the tumors. The prevalence of nuclear p53 positivity (79%) was significantly higher in patients with leukoplakia than in patients with tongue cancer (19%; χ2 = 34.32, r = –0.45, df = 1, p = 0.0001; odds ratio (OR) = 16.66, 95% CI, 5.25–52.86). Therefore, leukoplakia patients who show p53 expression have a higher risk of developing tongue cancer than those who do not show p53 expression. As the percentage of positivity of nuclear p53 was very low, none of the clinicopathological parameters or disease status showed any significant association with it. The interesting finding is that none of the female cancer patients showed nuclear p53 expression. Therefore, p53 accumulation is believed to be an early event in neoplastic progression of the tongue.

Molecular Alterations in Oral Carcinogenesis: Significant Risk Predictors in Malignant Transformation and Tumor Progression

In this study an attempt was made to establish the significance of a battery of molecular alterations and thereby identify risk predictors in oral carcinogenesis. For this purpose, EGFR, Stat3, H-ras, c-myc, p53, cyclin D1, p16, Rb, Ki-67 and Bcl-2 were localized immunohistochemically in normal mucosa (n=12), hyperplasia (n=35), dysplasia (n=25), early stage carcinoma (n=65) and advanced stage carcinoma (n=70). Deregulation occurred at an early stage and the number of alterations increased with disease progression. Using multivariate logistic regression analysis, the significant risk predictor for hyperplasia from normal mucosa was Ki-67 (OR=5.75, p=0.021); the significant risk predictors for dysplasia from hyperplasia were EGFR (OR=12.96, p=0.002), Stat3 (OR=17.16, p=0.0001), p16 (OR=5.50, p=0.039) and c-myc (OR=5.99, p=0.052); the significant risk predictors for early stage carcinoma from dysplasia were p53 (OR=6.63, p=0.0001) and Rb (OR=3.81, p=0.056); and the significant risk predictors for further progression were EGFR (OR=5.50, p=0.0001), Stat3 (OR=4.49, p=0.0001), H-ras (OR=4.05, p=0.001) and c-myc (OR=2.99, p=0.015). Cyclin D1 holds a key position linking upstream signaling pathways to cell cycle regulation. Gene products of the mitogenic signaling pathway play an equally significant role as cell cycle regulatory proteins in the hyperplasia-dysplasia-early-advanced-carcinoma sequence and together may provide a reference panel of markers for use in defining premalignant lesions and predicting the risk of malignant transformation and tumor progression.

A study of Ki-67 expression and its clinicopathological determinants in nondysplastic oral leukoplakia

Context:

Oral cancer is the third most prevalent malignancy in India. Leukoplakia is its most common precursor lesion.

Aims:

This study aimed at evaluation of the Ki-67 expression and thereby detection of the dysplastic potential in histopathologically nondysplastic oral leukoplakia (OL). Secondarily, another purpose was to correlate various clinicopathological factors with the labeling indices (LIs) of Ki-67 in those cases as well.

Settings and Design:

In total, 97 OL cases were examined. Relevant clinical and demographic information was retrieved from the pro forma, prefilled by the patients themselves during their first visit.

Subjects and Methods:

Ki-67 immunohistochemical staining was performed on paraffin-embedded tissue samples. Its LIs were calculated and correlated with different clinicopathological parameters using statistical software SPSS version 16.0.

Results:

58.8% (57 cases) lesions exhibited a Ki-67 positivity of ≤5%, and 25.8% (25 cases) lesions exhibited it in the range of 6%–25%. Only 15 (15.4%) patches were stained positively between 26% and 60%. Patients’ age beyond 50 years, nonhomogeneous leukoplakia, and tobacco addiction were the significant risk factors for high Ki-67 scores (P < 0.05).

Conclusions:

Ki-67 is an essential immunohistochemical marker for epithelial dysplasia in OL, especially when the conventional histopathology fails to appreciate the same. In this purpose, Ki-67 labeling on a routine basis delivers the most convenient results for patients aged above 50 years, and/or addicted to tobacco products, and/or suffering from nonhomogeneous patches.

Evaluation of histomorphological and immunohistochemical parameters as biomarkers of cervical lymph node metastasis in squamous cell carcinoma of oral cavity: A retrospective study

Introduction:

Oral squamous cell carcinoma (OSCC) is seen worldwide but is more common in India. Lymph node (LN) metastasis has been shown to be the strongest prognostic factor in OSCC. Many histopathological and immunohistochemical markers have been studied to predict the LN metastasis.

Aims:

To identify clinicopathological factors and immunohistochemical (IHC) biomarkers which predict cervical metastasis in OSCC patients.

Study and Design:

A total of 105 cases of OSCC were taken up for our study. Histopathological parameters such as tumor thickness, depth, degree of differentiation, pattern of invasion (POI), lymphovascular and neural invasion were assessed. IHC was done on all cases using antibodies against Ki-67, cyclin D, E-cadherin, p53, CD31 and each antibody was assessed according to the standard protocol.

Statistical Analysis:

To calculate the relation between clinical, histopathological parameter, IHC marker and the occurrence of LN metastasis, chi-square test was used. Variables were tested using multivariate logistic regression method to assess the predictive significance.

Results:

Out of 105 cases studied, 29 cases showed LN metastasis. Maximum numbers of cases affected were females with involvement of buccal mucosa. We found significant association of cervical LN metastasis with high grade of differentiation, lack of E-cadherin expression, high Ki-67 and cyclin D1 expression. In our study; tumor depth, thickness, extent of peritumoral lympho-plasmacytic infiltration, presence of eosinophils, tumor nest type, p53 and microvessel density (MVD) showed no significant correlation.

Conclusion:

Significant association of cervical LN metastasis with high grade of differentiation, lack of E-cadherin expression, high Ki-67 and cyclin D1 expression was seen.

Leuloplakia - review of a potentially malignant disorder

Leukoplakias are oral white lesions that have not been diagnosed as any other specific disease. They are grouped under premalignant lesions, now redesignated as potentially malignant disorders. Their significance lies in the fact that they have propensity for malignant transformation at a higher rate when compared to other oral lesions. This article reviews aetiology, epidemiology, clinical characteristics, histopathologic features, malignant potential and treatment of oral leukoplakia.

Study of the biologic behavior of odontogenic keratocyst and orthokeratinaized odontogenic cyst using TGF-alpha and P53 markers

Odontogenic keratocyst (OKC) is an aggressive cyst, and its recurrence rate is higher than that of other odontogenic cysts. Orthokeratinized odontogenic cyst (OOC) is less aggressive than OKC, but bears the probability of carcinomatous changes. In this study, we evaluated the expression and intensity of P53 and TGF-alpha in order to compare the biologic behavior or probable carcinomatous changes of these two cysts. In this cross-sectional study, 15 OKC and 15 OOC were stained immunohistochemically for P53 and TGF-alpha using the Novolink polymer method. Then, all slides were examined by an optical microscope with 400× magnification, and the stained cells in the basal and parabasal layers were counted. Finally, the results were analyzed by the Mann-Whitney and Wilcoxon tests (P-value<0.05). The difference between the expression of P53 and TGF alpha in the basal layer of OKC and OOC was not statistically significant (P-value>0.05), but the expression of P53 and TGF-alpha in the parabasal layer in OKC was statistically higher compared to OOC (P<0.05). Considering the known role of P53 and TGF-alpha in malignant changes and the higher expression of P53 and TGF-alpha in OKC compared to those in OOC, the probability of carcinomatous changes was higher in OKC than in OOC.

Comparative study of TGF-alpha and P53 markers' expression in odontogenic keratocyst and orthokeratinaized odontogenic cyst

BACKGROUND

Odontogenic keratocyst (OKC) is an aggressive cyst and its recurrence is higher than other odontogenic cysts, orthokeratinized odontogenic cyst (OOC) is a cyst with moderate biological behavior in comparison with OKC, but with the probability of carcinomatous changes. The present study aims to evaluate the quantity and intensity of the expression of P53 protein and transforming growth factor alpha (TGF-alpha) in OKC and OOC in order to compare the biologic behavior of these two cysts.

MATERIALS AND METHODS

This is a cross-sectional study. The samples include 30 cysts (15 OKC and 15 OOC), all stained immunohistochemically for P53 protein and TGF-alpha by the Novolinke polymer method. Then, all the cases were examined with an optical microscope with Χ400 magnification and the stained cells were counted in the basal and parabasal layers. Finally the results were analyzed by the Mann-and Wilcoxon tests (P value < 0.05).

RESULTS

The difference between the expression of P53 protein in the basal layer in OKC and OOC was not statistically significant (P value = 0.076). The difference between the expression of P53 protein in the parabasal layer in OKC and OOC was statistically significant (P value = 0.003); moreover, the difference between the expression of TGF-alpha in the basal layer in OKC and OOC was not statistically significant (P value = 0.284). The difference between the expression of TGF-alpha in the parabasal layer in OKC and OOC was statistically significant (P value = 0.015).

CONCLUSION

Since there was a higher expression of P53 protein and TGF-alpha in OKC compared to those in OOC, the probability of carcinomatous changes was at least theoretically higher in OKC than in OOC.

Expression of p53 protein and ki-67 antigen in oral premalignant lesions and oral squamous cell carcinomas: An immunohistochemical study

Aim:

To study expression of p53 protein and ki-67 antigen in normal, non-dysplastic, dysplastic, premalignant and malignant lesions of the oral mucosa.

Materials and Methods:

The standard immunohistochemical method along with MIB-1 and DO-7; DAKO antibodies was used to study the expression of p53 and ki-67 in paraffin-embedded tissue specimens.

Results:

All samples studied showed positive staining for p53 and ki-67. Only one case each from leukoplakia and oral squamous cell carcinoma (OSCC) groups showed negative staining for ki-67. The staining was confined to basal layer in most of the cases except OSCC in which it was seen in all layers. The intensity of staining was moderate to intense. The percentage of p53-positive cells in normal mucosa was 15-25% which was increased to 95% in malignant mucosa. Statistical analysis revealed that the expression of p53 and ki-67 increases as normal oral mucosa becomes dysplastic and undergoes malignant transformation.

Conclusion:

These results emphasize the potential use of p53 protein and ki-67 antigen as markers of malignant transformation and carcinogenesis in oral premalignant lesions, conditions and OSCC, respectively; and in future they may serve as prognostic tools in the early detection of malignant transformation in oral premalignant lesions and conditions.

Computer-assisted analysis of cell proliferation markers in oral lesions

Abnormalities in any component of the cell cycle regulatory machine may result in oral cancer, and markers of cell proliferation have been used to determine the prognosis of tumor progression. The aim of this study was to determine whether silver-stained nucleolar organizer region (AgNOR) and Ki-67 measurements could improve the assessment of growth rates in oral lesions. Eighty-three oral biopsies were studied, 20 of which were classified as fibrous inflammatory hyperplasia (FIH), 40 as leukoplakia (LKP) and 23 as oral squamous cell carcinoma (OSCC). Within the LKP group, 22 out of 29 biopsies were diagnosed as non-dysplastic leukoplakia (LK) and 18 as dysplastic leukoplakia (DLK), presenting discrete, moderate and severe dysplasia. Ki-67 immunolabeling of the lesions increased steadily in the following order: FIH, DLK, LK and OSCC, indicating that Ki-67 is a good marker for predicting the proliferative fraction among benign, premalignant and malignant oral lesions. The median values of AgNOR parameters indicate that the morphometric index gives better results regarding the proliferative rate than the numerical one. A series of linear regressions between AgNOR parameters and Ki-67 showed positive associations. We conclude that a combination of Ki-67 and morphometric AgNOR analyses could be used as an aid in the determination of the proliferative status of oral epithelial cells in oral cancer.

The association between epithelial proliferation and disease progression in the oral mucosa

The purpose of this study was to examine the possible association between epithelial proliferation and disease progression in the oral mucosa. Archival specimens of normal oral mucosa (n = 12), dysplasia (n = 17) and squamous cell carcinoma (n = 18) were sectioned and proliferating cells visualised by staining with Ki-67 antibody. The proliferative index of the epithelium (PI) was determined by total cell counts and point counting. Similar results were obtained using either method. Comparison of the three groups of tissues by one-way analysis of variance showed a significant increase in PI with increasing lesion severity (p < 0.001). The PI of both dysplasia and carcinoma groups was significantly higher than that of normal oral mucosa (p < 0.001). However, the difference between dysplasia and carcinoma groups was not significant. PI was not associated with tobacco or alcohol consumption. We therefore conclude that Ki-67 expression is an early marker of disease progression in the oral mucosa but, on its own, is not a good indicator of neoplastic transformation.

Immunophenotypic analysis of normal mucosa and squamous cell carcinoma of the oral cavity

Detection of tumor-associated alterations in peritumoral normal mucosa may give insight into the molecular pathogenesis of oral cancer. In the present study, 100 archival oral squamous cell carcinomaswith adjacent nontumorous mucosa were immunohistochemically investigated with antibodies against p53, Mdm2, Bcl-2, WAF1, MIB1, epidermal growth factor receptor (EGF-R), and various CD44 isoforms. Additionally a standardized argyrophilic nucleolar organizer region (AgNOR)-associated proteins analysis was performed. No correlation was found between p53, Mdm2, Bcl-2, and WAF1 immunophenotypes of the respective tumors and adjacent mucosa. The proliferation-associated markers MIB1 and AgNORs showed a statistically significant sequential increase from normal to dysplastic mucosa to invasive carcinoma. Investigation of various CD44 adhesion molecules revealed a highly variable expression pattern in overt carcinomas with a significantly decreased expression of CD44 v4 and v9 variants and unaltered strong expression of v5 and v6 isoforms compared with normal oral epithelium. We conclude that proliferation markers (MIB1 and AgNORs), as well as selected CD44 isoforms, represent useful markers for the assessment of precancerous lesions. They may be utilized for screening patients at high risk for the development of oral cancer.