Upper aerodigestive tract squamous dysplasia: correlation with p16, p53, pRb, and Ki-67 expression

Human papillomavirus expression in relation to biological behavior, Ki-67 proliferative marker, and P53 prognostic marker in Schneiderian papilloma

Various malignant and benign tumors can arise in the sinonasal cavity, including inverted papilloma (IP), a benign neoplasm with unique clinical characteristics. However, the mechanisms involved in the recurrence, occurrence, and malignant transformation of IP remain debatable. This study aimed to investigate the impact of human papillomavirus (HPV) infections on IP by comparing the number of infections in cases with epithelial tissue dysplasia and explore the predictive role of proliferative and prognostic markers in dysplasia. Tissue blocks from 35 cases of sinonasal papilloma, collected between 2015 and 2021 from the laboratory archives of the Medical City of Ghazi Al-Hererri Hospital in Baghdad, Iraq, were immunohistochemically stained with monoclonal antibodies (mAbs) to detect Ki-67 and p53. A quantitative immunohistochemical analysis was conducted to analyze the results. Polymerase chain reaction (PCR) was performed to detect HPV genotypes 16/18 and 6/11 in the tissues. There was an insignificant increase in Ki-67 and p53 expression in inverted papillomas with dysplasia. HPV11 was the most prevalent genotype in 34.3% of the patients, followed by HPV16 and HPV18 in 31.4% of the patients for each virus. The least common virus detected was human papillomavirus 6 (8.6%), which did not show any significant association with the degree of dysplasia. Viral detection proliferation and apoptosis had no impact on tumor dysplasia amongst all the patients, showing no relationship with the evaluated cases.

Significant association between 53 BP1 expression and grade of intraepithelial neoplasia of esophagus: Alteration during esophageal carcinogenesis

BACKGROUND

Abnormal DNA damage response (DDR) leads to genomic instability and carcinogenesis. P53-binding protein 1 (53 BP1), a DDR molecule, is known to accumulate at the sites of DNA double-strand breaks. The aim of this study was to analyze the expression pattern of 53 BP1-nuclear foci (NF) in esophageal neoplasms in order to visualize the state of DDR in esophageal carcinogenesis and to clarify its significance in the molecular pathology of the disease.

METHODS

A total of 61 lesions from 22 surgically resected samples of esophageal cancer, including histologically normal squamous epithelium, low-grade intraepithelial neoplasia (LG-IN), high-grade intraepithelial neoplasia (HG-IN), carcinoma in situ (CIS), and invasive squamous cell carcinoma (SCC), were included in the study. 53 BP1 and Ki-67 expression were analyzed by double-labeled immunofluorescence.

RESULTS

The number of discrete 53 BP1-NF increased as the tumor progressed from normal epithelium through LG-IN, HG-IN, CIS, and SCC. 53 BP1-NF larger than 1 μm in diameter (large foci), indicating intensive DDR, also showed a stepwise increase during the progression of carcinogenesis. Of note, large foci of 53 BP1 were found in significantly higher numbers in HG-IN than in LG-IN. Furthermore, localization of 53 BP1-NF in Ki-67-positive cells, indicating the abnormal timing of DDR, also increased with malignancy progression.

CONCLUSIONS

53 BP1-NF accumulation increases during cancer progression from LG-IN to HG-IN to CIS to SCC. Detection of 53 BP1-NF by immunofluorescence, especially large foci, is a feasible method of estimating DNA instability and the malignant potential of esophageal intraepithelial neoplasia.

Gastro-duodenal fluid induced nuclear factor-κappaB activation and early pre-malignant alterations in murine hypopharyngeal mucosa

We recently described the role of gastro-duodenal fluids (GDFs) in generating changes consistent with hypopharyngeal neoplasia through activation of NF-κB pathway, using an in vitro model of human hypopharyngeal normal keratinocytes. Here, we further provide evidence that gastro-duodenal reflux is a risk factor for early pre-malignant alterations in hypopharyngeal mucosa (HM) related to an activated NF-κB oncogenic pathway, using both an in vitro and a novel in vivo model of C57Bl/6J mice. Histological, immunohistochemical and automated quantitative analysis documents significant NF-κB activation and early pre-malignant alterations in HM topically exposed to GDFs, compared to acid alone and other controls. Early pre-malignant histologic lesions exhibited increased Ki67, CK14 and ΔNp63, cell proliferation markers, changes of cell adhesion molecules, E-Cadherin and β-catenin, and STAT3 activation. The in vivo effect of NF-κB activation is positively correlated with p-STAT3, Ki67, CK14 or β-catenin expression, while GDFs induce significant transcriptional activation of RELA(p65), bcl-2, TNF-α, STAT3, EGFR and wnt5A, in vivo. Our in vivo model demonstrates selectively activated NF-κB in response to topically administrated GDFs, leading to early pre-malignant events in HM.

Morphometric analysis of Ki-67 and p16 expression in laryngeal precursor lesions

Laryngeal precursor lesions represent areas of altered epithelium with an increased likelihood for progression to squamous cell carcinoma. The exact molecular mechanisms of malignant transformation of laryngeal mucosa are not completely clear, but are certainly due to deregulation of cell proliferation. To assess the potential value of the p16 and Ki-67 as markers of malignant progression, we undertook a retrospective immunohistochemical and morphometric analysis on biopsy specimens from patients with precancerous lesions in the larynx. Morphometric analysis of samples stained with p16 antibody showed epithelial cell positivity in 29 (100 %) of samples with simple hyperplasia, 31 (100 %) samples with basal/parabasal cell hyperplasia, 23 (88 %) samples with atypical hyperplasia and 20 (95 %) samples with in situ carcinoma. There was a significant difference in percentage of p16-positive cells between samples with simple hyperplasia and samples with in situ carcinoma. Morphometric analysis of samples stained with Ki-67 antibody showed epithelial cell positivity in 27 (93 %) of samples with simple hyperplasia, 30 (97 %) samples with basal/parabasal cell hyperplasia, 26 (100 %) samples with atypical hyperplasia and 18 (86 %) samples with in situ carcinoma. There was a significant difference not only in the percentage of Ki-67-positive cells between samples with simple hyperplasia and samples with in situ carcinoma, but also between samples with simple and basal/parabasal cell hyperplasia. Laryngeal epithelial precursor lesions show significantly opposite patterns in p16 and Ki-67 immunopositivity. Simple hyperplasia on average shows 12 % of Ki-67-positive cells and 46 % of p16-positive cells. In situ carcinoma on average shows 23 % of Ki-67-positive cells and 36 % of p16-positive cells.

Ki67, p27 and p53 Expression in Squamous Epithelial Lesions of Larynx

Precise assessment of the biological behavior and progression of squamous epithelial lesions of the larynx with a view to predict the prognosis and therapeutic challenges remains an elusive goal. The knowledge and data regarding the expression of proliferative markers indicating the biological activity in different histological grades of squamous epithelial lesions are lacking till date. To evaluate the relationship between Ki67, p27 and p53 expression as well as topographic distribution of Ki67 with the histological subtypes or grades of laryngeal squamous intraepithelial and invasive lesions. Sixty-two consecutive cases with histologically documented intraepithelial and invasive squamous lesion were studied for Ki67, p27 and p53 expression. Mann-Whitney U, Kruskal-Wallis and Spearman's correlation tests were used for statistical analysis. The mean Ki67 labeling index in hyperplasia, dysplasia and carcinoma were 12.15, 22.03 and 35.53 % respectively and this difference was statistically significant (P < 0.05). There was strong positive correlation between Ki67 labeling index and increasing grades of squamous lesions. p27 expression was progressively decreased and p53 expression was progressively increased as the lesions progressed from hyperplasia to dysplasia and dysplasia to carcinoma. The topographic distribution of Ki67 positive cells increased with progressive grades of dysplasia. The Ki67 labeling index correlates well with the histological grade of both intraepithelial and invasive lesions of the larynx. And the topographic distribution of Ki67 expression depends on the grade of the dysplasia. Hence, Ki67 expression has a definite role in predicting the biological behavior of the lesions.

Ki-67 and ProExC are useful immunohistochemical markers in esophageal squamous intraepithelial neoplasia

Esophageal squamous intraepithelial neoplasia has been widely recognized as a precursor lesion for esophageal squamous cell carcinoma. Early detection offers the best prognosis for esophageal squamous cell carcinoma. The differentiation of squamous dysplasia from reactive change and the classification of squamous dysplasia into high-grade or low-grade are sometimes subjective and challenging. In this study, we sought to evaluate multiple biomarkers and to develop clinically useful adjunct tools for difficult esophageal squamous intraepithelial neoplasia cases. Immunohistochemical stains using antibodies against Ki-67, ProExC, p16, and p53 were performed on esophageal biopsy or resection specimens from 25 patients including 35 foci of high-grade dysplasia and 25 foci of low-grade dysplasia, and from 10 control cases containing 52 foci of normal/reactive hyperplasia. In situ hybridization tests for human papillomavirus were performed in 11 cases. The immunostains for all 4 markers were scored as negative, intermediate, and strong according to established criteria. Intermediate and strong Ki-67 and ProExC staining showed similar detecting power and exhibited very high sensitivity and specificity for distinguishing normal/reactive hyperplasia from esophageal squamous intraepithelial neoplasia and normal/reactive hyperplasia from low-grade esophageal squamous intraepithelial neoplasia. Strong Ki-67 staining was exclusively seen in high-grade esophageal squamous intraepithelial neoplasia, which provided additional value in distinguishing high-grade from low-grade esophageal squamous intraepithelial neoplasia. Strong ProExC staining was also seen in most high-grade esophageal squamous intraepithelial neoplasia foci (80%). Although the frequencies of intermediate/strong staining patterns of p53 increased with increasing degree of dysplasia, the sensitivity of p53 was much lower than that of Ki-67 and ProExC. p16 did not show consistent immunostain pattern in the normal/reactive hyperplasia and esophageal squamous intraepithelial neoplasia. Two (18%) of 11 tested cases were positive for human papillomavirus infection. This study demonstrates that both Ki-67 and ProExC can be used as an adjunct tool for diagnosing difficult cases of esophageal squamous intraepithelial neoplasia.

p16 and MIB1 improve the sensitivity and specificity of the diagnosis of high grade squamous intraepithelial lesions: methodological issues in a report of 447 biopsies with consensus diagnosis and HPV HCII testing

OBJECTIVE

Many investigators are studying the additional value of biomarkers to improve histopathologic agreement, but few are using the same methodologies. Our objectives in this analysis to differentiate High-grade Squamous Intraepithelial lesions (HGSIL) from Low Grade Squamous Intraepithelial Lesions (LGSIL), atypia, and normal were: (1) to examine the rate of Human Papilloma Virus High-Risk positivity (HPV HR+), (2) to compare and grade the basal, parabasal, intermediate, and superficial layer staining of each marker, (3) to determine the optimal qualitative threshold for markers, (4) to compare p16 and MIB1 agreement, and (5) to examine the sensitivities and specificities using each markers alone and together.

METHODS

A sample of biopsies from 208 patients were chosen from a total of 1850 patients and 3735 biopsies obtained during the course of ongoing optical trials. At least two independent blinded reviews were performed for each biopsy. A third review was performed if there was a disagreement between the two reviews. Both endocervical and ectocervical samples were stained for p16 and MIB1. A grading system that is delineated in the text ranged from 0 to 3 for both markers and each biopsy was scored by each cell layer. Frequencies, sensitivities, and specificities were calculated using Statistica. An ANOVA was used to compare p16 and MIB1 staining in the epithelial layers. Finally the sensitivity and specificity of each marker alone and together were examined.

RESULTS

453 specimens from 208 patients whose final diagnoses were normal (n=244), low-grade (LG) (n=59), and high-grade (HG) (n=144) were selected for analysis. 447 of 453 specimens were available for staining. Most LG and HG lesions were HPV HR positive. Endocervical samples stained positive less often than ectocervix and often results were discordant from ectocervical results. The analysis by layers showed pronounced increases in staining of both p16 and MIB1 as lesions progressed from normal to LG to HG. The cutoff or threshold for p16 was 0 versus 1-3 while for MIB1 it was 0-1 versus 2-3. Using the intermediate epithelial layer measurement of both p16 and MIB1 in HPV High-Risk Positive separated the normal tissue from LGSIL, normal from HGSIL, and LGSIL from HGSIL by a statistically significant margin (p<0.05). Each marker had sensitivities and specificities for the diagnosis of HGSIL versus LGSIL and normal of approximately 85-90% and this improved by 5% for both sensitivity and specificity when used together (p16 sensitivity 90%, specificity 85%; MIB1 sensitivity 89%, specificity 87%; together sensitivity 94%, specificity 90%).

CONCLUSION

Several important methodological issues have been studied. Overall, p16 and MIB1 are promising markers to help pathologists differentiate HG lesions from all else. The staining of the endocervix and the ectocervix do not always agree, and the ectocervix more often stains positive with the presence of HGSIL. Each marker is helpful and both are helpful together. In conclusion, both markers are useful for the confirmation of HG lesions.