Expression of P53 Protein and Ki-67 Antigen in Oral Leukoplakia with Different Histopathological Grades of Epithelial Dysplasia

Potential Immunohistochemical Biomarkers for Grading Oral Dysplasia: A Literature Review

Oral cancer is a prevalent global health issue, with significant morbidity and mortality rates. Despite available preventive measures, it remains one of the most common cancers, emphasising the need for improved diagnostic and prognostic tools. This review focuses on oral potentially malignant disorders (OPMDs), precursors to oral cancer, specifically emphasising oral epithelial dysplasia (OED). The World Health Organisation (WHO) provides a three-tier grading system for OED, and recent updates have expanded the criteria to enhance diagnostic precision. In the prognostic evaluation of OED, histological grading is presently regarded as the gold standard; however, its subjectivity and unreliability in anticipating malignant transformation or recurrence pose notable limitations. The primary objective is to investigate whether specific immunohistochemical biomarkers can enhance OED grading assessment according to the WHO classification. Biomarkers exhibit significant potential for comprehensive cancer risk evaluation, early detection, diagnosis, prognosis, and treatment optimisation. Technological advancements, including sequencing and nanotechnology, have expanded detection capabilities. Some analysed biomarkers are most frequently chosen, such as p53, Ki-67, cadherins/catenins, and other proteins used to differentiate OED grades. However, further research is needed to confirm these findings and discover new potential biomarkers for precise dysplasia grading and minimally invasive assessment of the risk of malignant transformation.

Correlation of p53 expression with Clinical Presentation and Prognosis of Oral Squamous Cell Carcinoma Patients: A Pilot Study

Mutations of p53 gene is one of the most common events in human cancers including oral squamous cell carcinoma (OSCC). However, its role in carcinogenesis and association with regard to prognosis is still under investigation and unclear. The aim was to study the expression of p53 in patients of OSCC and correlation with clinical presentation and prognosis. In this retrospective observational pilot study, we examined expression of p53 in 50 histologically diagnosed cases of OSCC and correlated it with initial clinical presentation and clinical events in follow up period. p53 expression was significantly negative (94%) in patients with history of only oral tobacco consumption while cases with additional history of smoking or alcohol were positive (p = 0.0001 and 0.011). On the other hand, aggressive course of the disease was found to be significant with p53 positivity in the form of lymph nodal extension (13 out of 17 cases) (p = 0.011) and recurrence (6 out of 10 cases) (p = 0.024). p53 was overexpressed (positive) in predisposing factors like smoking and alcohol but not in OSCC associated with chewing tobacco. p53 overexpression is also associated with advanced TNM stage. To the best of our knowledge, this is the first report where association of p53 overexpression and oral tobacco consumption associated OSCC was not observed and we recommend that carcinogenic events in chewing tobacco induced OSCC should be studied separately for its unique set of mutations.

Podoplanin Expression Independently and Jointly with Oral Epithelial Dysplasia Grade Acts as a Potential Biomarker of Malignant Transformation in Oral Leukoplakia

Our aim was to evaluate the expression of biomarkers, CD44v6, CD147, EGFR, p53, p63, p73, p16, and podoplanin in oral leukoplakias (OL) and to assess their potential for prediction of malignant transformation (MT). We analyzed the expression of CD44v6, CD147, EGFR, p53, p63, p73, p16, and podoplanin by immunohistochemistry in 52 OL, comprised of 41 low-grade (LG) dysplasia and 11 high-grade (HG) cases. Twelve healthy normal tissues (NT) were also included. Univariate and multivariate analysis were performed to evaluate any association with MT. Variable expression among the studied markers was observed, with a significant increase of high expression from NT to LG and HG cases in CD44v6 (p = 0.002), P53 (p = 0.002), P73 (p = 0.043), and podoplanin (p < 0.001). In multivariate analysis, cases with high podoplanin score showed a significant increased risk of MT (HR of 10.148 (95% CI of 1.503−68.532; p = 0.017). Furthermore, podoplanin combined with binary dysplasia grade obtained a HR of 10.238 (95% CI of 2.06−50.889; p = 0.004). To conclude, CD44v6, p53, p73, and podoplanin showed an increasing expression along the natural history of oral carcinogenesis. Podoplanin expression independently or combined with dysplasia grade could be useful predictive markers of MT in OL.

Multiple approaches to oral epithelial dysplasia degree analyses: a pilot study

BACKGROUND

Oral epithelial dysplasia (OED) is the presence of cells of an abnormal type within a tissue, which may signify a stage preceding the development of cancer. Our aim was to determine the interrelation between the expression of multiple molecular markers and the histological features of oral dysplasia.

METHODS

Fifteen samples of OED (five for each severity degree) were analyzed through software assisted image cytometry nuclear morphology. p53 (wild-type and mutated form), Bax and Bcl2 expression was immunohistochemically determined, and the gene expression of MMP1, MMP2, MMP9 and hTERT was determined by RT-PCR. The mean, standard deviation, ANOVA and Fisher's Exact Test (P<0.05) were performed.

RESULTS

Our analysis indicated congruence between the software-assisted measurement of nuclear morphology and severity degree. Only five samples were positive to p53-mutated form; and Bax was more expressed than Bcl-2. hTERT expression was significantly expressed in relation to severity, and MMP1 was predominantly expressed, followed by MMP9 and MMP2.

CONCLUSIONS

Our results reinforce that software-assisted measurement is an alternative to severity degree determination. MMP1 is an important marker for severity dysplasia degree; however, the predominant expression of Bax over Bcl-2 suggests that this pro-apoptotic state could be used to minorize the progression, perhaps, as a future therapeutic target.

Expression of p53, p63, podoplanin and Ki-67 in recurring versus non-recurring oral leukoplakia

Oral leukoplakia (OL), a potentially malignant disorder, recurs in 40% of cases after surgical removal. Recurrence is a risk factor for malignant transformation. We aimed to examine the prognostic significance of four biomarkers related to cell proliferation: p53, p63, podoplanin (PDPN) and Ki-67 in predicting recurrence. Formalin-fixed-paraffin-embedded specimens from excised OL (n = 73, 33 recurrent; 40 non-recurrent) were collected in a prospective study. Immunohistochemistry was used to visualise expression of p53, p63, PDPN and Ki-67. Image analysis software was used for quantification of p53-, p63- and Ki-67-expressing cells, while PDPN was analysed visually. The expression of all four proteins were higher in recurrent compared with non-recurrent OL, only expression of p53 was statistically significant. In uni- and multivariable Cox regression analyses of individual markers, expression of p63 was significantly associated with higher recurrence risk (p = 0.047). OL with a combined high expression of both p53 and p63 had a significantly higher risk to recur [Log Rank, p = 0.036; multivariate Cox, HR: 2.48 (1.13–5.44; p = 0.024)]. Combination of p53 and p63 expression may be used as a prognostic biomarker for recurrence of OL.

Intralesional Infiltrations of Cell-Free Filtrates Derived from Human Diabetic Tissues Delay the Healing Process and Recreate Diabetes Histopathological Changes in Healthy Rats

Lower limb ulcers in type-2 diabetic patients are a frequent complication that tributes to amputation and reduces survival. We hypothesized that diabetic healing impairment and other histopathologic hallmarks are mediated by a T2DM-induced tissue priming/metabolic memory that can be transferred from humans to healthy recipient animals and consequently reproduce diabetic donor’s phenotypes. We examined the effect of human T2DM tissue homogenates injected into non-diabetic rat excisional wounds. Fresh granulation tissue, popliteal artery, and peroneal nerve of patients with T2DM were obtained following amputation. Post-mammoplasty granulation and post-traumatic amputation-tissue of normal subjects acted as controls. The homogenates were intralesionally injected for 6–7 days into rats’ excisional thickness wounds. Infiltration with the different homogenates caused impaired wound closure, inflammation, nerve degeneration, and arterial thickening (all P &lt; 0.01 vs relevant control) resembling histopathology of diabetic donor tissues. Control materials caused marginal inflammation only. Infiltration with glycated bovine albumin provoked inflammation and wound healing delay but did not induce arterial thickening. The reproduction of human diabetic traits in healthy recipient animals through a tissue homogenate support the notion on the existence of tissue metabolic memory-associated and transmissible factors, involved in the pathogenesis of diabetic complications. These may have futuristic clinical implications for medical interventions.

Theoretical Background to Automated Diagnosing of Oral Leukoplakia: A Preliminary Report

Oral leukoplakia represents the most common oral potentially malignant disorder, so early diagnosis of leukoplakia is important. The aim of this study is to propose an effective texture analysis algorithm for oral leukoplakia diagnosis. Thirty-five patients affected by leukoplakia were included in this study. Intraoral photography of normal oral mucosa and leukoplakia were taken and processed for texture analysis. Two features of texture, run length matrix and co-occurrence matrix, were analyzed. Difference was checked by ANOVA. Factor analysis and classification by the artificial neural network were performed. Results revealed easy possible differentiation leukoplakia from normal mucosa (p < 0.05). Neural network discrimination shows full leukoplakia recognition (sensitivity 100%) and specificity 97%. This objective analysis in the neural network revealed that involving 3 textural features into optical analysis of the oral mucosa leads to proper diagnosis of leukoplakia. Application of texture analysis for leukoplakia is a promising diagnostic method.

Application of Texture and Fractal Dimension Analysis to Estimate Effectiveness of Oral Leukoplakia Treatment Using an Er:YAG Laser-A Prospective Study

BACKGROUND

Oral leukoplakia (OL) is a potential neoplasmic lesion. The aim of this study was to apply texture analysis (TA) and fractal dimension analysis (FDA) to estimate the effectiveness of OL treatment using an Er:YAG laser.

METHODS

Eighteen patients with 32 lesions were treated. Laser procedures were conducted using the LiteTouch™ Er:YAG Dental Laser. The diameter of the operational tip was 1.3 mm, the power was 50 mJ, the frequency was 50 Hz, and the wavelength was 2940 nm. TA was based on long and short-run emphasis inverse moments, difference entropy, inverse difference moment, and wavelet decomposition for two-dimensional photography. FDA was measured using the box-counting method.

RESULTS

Total response was achieved in 50% of lesions, partial response was observed in 47%, and 3% of lesions did not respond to treatment. Recurrence occurred in 34% of lesions. TA features indicated pathological images depicting leukoplakia and complete reconstruction of the correct mucosal image after laser ablation. The discrete wavelet transformation feature detects much larger structures than the properties derived from the run-length matrix and co-occurrence matrix.

CONCLUSIONS

The Er:YAG laser is an effective treatment method in cases of oral leukoplakia. Leukoplakia treatment by Er:YAG laser is an effective modality, as revealed by the oral mucosa microstructure. TA and FDA are promising methods to estimate the effectiveness of OL treatment.

Benign Alveolar Ridge Keratosis: Clinical and Histopathologic Analysis of 167 Cases

Benign alveolar ridge keratosis (BARK), the intraoral counterpart of cutaneous lichen simplex chronicus, is a reactive hyperkeratosis caused by trauma or friction that presents as a poorly demarcated white papule or plaque on the keratinized mucosa of the retromolar pad or alveolar ridge mucosa (often edentulous). This is a clinical and histopathologic analysis of BARK including evaluation of p53 expression in selected cases. One hundred and sixty-seven cases of BARK were identified from 2016 to 2017 and 112 (67.1%) occurred in males with a median age of 56 years (range 15-86). The retromolar pad was affected in 107 (64.1%) cases and the edentulous alveolar mucosa in 60 (35.9%) cases, with 17.4% of the cases presenting bilaterally. BARK showed hyperkeratosis often with wedge-shaped hypergranulosis and occasional focal parakeratosis. The epithelium exhibited acanthosis and surface corrugation with tapered rete ridges often interconnected at the tips. The study for p53 performed in 12 cases showed less than 25% nuclear positivity. BARK is a distinct benign clinicopathologic entity caused by friction, which should be clearly distinguished from true leukoplakia, a potentially malignant disorder.

Atypical immunohistochemical patterns can complement the histopathological diagnosis of oral premalignant lesions

BACKGROUND

The histopathological diagnosis of oral premalignant lesions (OPLs) such as oral epithelial dysplasia (ED) and carcinoma in situ (CIS), as well as epithelial hyperplasia (EHP), is important for the early detection and precise treatment of oral squamous cell carcinoma. However, the standardization of detection and treatment by histological criteria alone remains challenging owing to the complicated and varied histology. We evaluated practically useful immunohistochemical (IHC) markers that might complement the histopathological diagnosis of OPLs.

METHODS

We re-evaluated the histopathological diagnoses and IHC patterns of Ki-67, TP53, CK13, and CK17 in 200 cases of OPLs and performed multiple logistic regression analyses for their predictive accuracy.

RESULTS

We identified and compared atypical IHC patterns in OPLs and in the normal epithelium. Ki-67 expression showed specific patterns in categorized OPLs as EHP, low-grade dysplasia (LED), high-grade dysplasia (HED), and CIS. Multiple logistic regression analyses in the quadrant categories revealed that EHP and CIS had high predictive accuracies of 90.1% and 96.2%, respectively, and in binary categories, combined EHP and LED versus combined HED and CIS showed predictive accuracies of 92.1% and 89.9%, respectively. Binominal logistic regression analysis between each quadrant category revealed satisfactory predictive accuracy of EHP vs. LED, LED vs. HED, and HED vs. CIS (75.2%, 78.9%, and 87.9%, respectively), and Ki-67 showed the highest adjusted odds ratio, followed by TP53.

CONCLUSION

The proposed atypical IHC patterns might serve as useful markers to supplement the morphological diagnosis of OPLs, and established IHC methods for Ki-67 and TP53 might provide stable results.

Analysis of Ki-67 Expression in Oral Premalignant Lesions and Normal Oral Mucosa: An Immunohistochemical Study

Aim:

This study aimed to evaluate the Ki-67 expression in oral premalignant lesions and normal oral mucosa.

Materials and Methods:

The cases were selected on the basis of the details obtained from the patients. A total of 45 specimens were divided into three groups: Group 1 (normal mucosa), Group 2 (clinically and histologically diagnosed as oral lichen planus), and Group 3 (clinically and histologically diagnosed as leukoplakia). Specimens were prepared and the slides for Ki-67 were observed under light microscope with a magnification of ×400. The tissue samples were thoroughly examined, and the pattern of expression was analyzed semiquantitatively by counting the number of positive cells.

Results:

The mean positive cell count of normal mucosa was 23.20 ± 2.89, of oral lichen planus was 42.82 ± 2.65, and of leukoplakia was 82.14 ± 3.10. There was a statistically significant difference of expression observed between the groups (P < 0.001). On multiple comparisons using Tukey post hoc test, a statistical difference was found between all the three groups.

Conclusion:

Ki-67 is an easily applicable marker of cell proliferation whose expression correlates well with the disease progression.