P53 In Oral Squamous Cell Carcinoma Research Articles

Immunohistochemical Expression of p16 and p53 as Prognostic Indicator in Oral Squamous Cell Carcinoma: A Cross-sectional Study

Introduction: Head and Neck Squamous Cell Carcinoma (HNSCC) is the sixth most common cancer globally and the seventh most common cause of cancer-related mortality. Tobacco use, alcohol consumption, and Human Papillomavirus (HPV) infection are prominent risk factors for HNSCC. HPVpositive Oral Squamous Cell Carcinoma (OSCC) differs from HPV-negative OSCC in terms of risk factors, preferential site of origin, age, histomorphological features, molecular genetic alterations, and prognosis. The prominent basaloid morphology and lobular growth of OSCCs are associated with p16 positivity and p53 negativity, respectively. Aim: To establish the immunohistochemical expression of p16 (p16INK4a) and p53 in OSCC and to assess their relationship with specific histomorphological features, in the form of solid growth of cells in a lobular configuration, small crowded cells with scant cytoplasm, dark hyperchromatic nuclei without nucleoli. Materials and Methods: The cross-sectional study involved fifty cases of OSCC over a two-year period from January 2017 to January 2019 at Army Hospital (R and R) Delhi Cantt. The intensity of p16 and p53 protein expression was graded as follows: no staining (0), weak staining (1), moderate staining (2), and strong staining (3). The proportion/percentage of staining for p16 and p53 protein expression was calculated as follows: 1-4% (1), 5-19% (2), 20-39% (3), 40-59% (4), 60-79% (5), and 80-100% (6) cells stained. A quick score of 0-1 (negative), 2-3 (weak positive), 4-5 (moderate positive), and >6 (strong positive) was assessed. Cross tables were generated and the Chi-square test was used for testing associations. The Statistical Software for Data Science (STATA)-14 was used for statistical analysis. Results: A total of 50 cases of OSCC were analysed for histomorphological features and immunohistochemical patterns of p16 and p53. The age distribution showed that 8 (16%), 9 (18%), 18 (36%), 13 (26%), and 2 (4%) of the patients were in the age groups of 31-40 years, 41-50 years, 51-60 years, 61-70 years, and above 70 years, respectively. The gender distribution noted 42 (84%) males and 8 (16%) females. Genital and nongenital mucosa are usually involved by HPV subtypes 6, 11, 16, 18, and 16, 18, 11, 13, 2, respectively. HPV-16 has been demonstrated in 90-95% of all HPV-positive HNSCC cases, followed by HPV-18, HPV-31, and HPV-33. p53 is considered the guardian of the genome and controls the expression and activity of proteins involved in cell cycle regulation, DNA repair, cellular senescence, and apoptosis. More than 50% of all primary HNSCC exhibit p53 mutation. Conclusion: A significant correlation was observed between age, dysplasia, keratinisation, basaloid morphology versus p16 expression, and lobular growth, histological grade versus p53. An inverse relationship between p16 and p53 expressions was observed. The immunohistochemical expression of p16 as an immunohistochemical marker of HPV, along with p53, is recommended. Due to the constraint of the study period, the survival of the patients could not be assessed in correlation with p16 and p53 expression.

Nutlin-3 suppresses tumorigenesis and progression of oral squamous cell carcinoma and enhances chemosensitivity to cisplatin.

Oral squamous cell carcinoma (OSCC) is an epithelial malignant tumor with great challenges of tumor metastasis and drug resistance. Nutlin-3 is a MDM2 inhibitor that can potently activate tumor suppressor gene p53. However, the exact role of Nutlin-3 in OSCC has not been identified yet. SCC-9 cells were treated with 0, 2.5, 5, 10, 20μM Nutlin3. MDM2 and p53 protein levels were assessed using western blot analysis. Then, CCK8 assay, clone formation assay, TUNEL staining, wound healing and transwell assays were conducted to analyze the influences of Nutlin3 on the proliferation, apoptosis, migration, and invasion in SCC-9 cells. Moreover, SCC-9 cells were co-treated with 0, 0.5, 1, 2.5, 5μM cisplatin and Nutlin3 to determine the effect of Nutlin3 on cisplatin chemosensitivity in OSCC. As expected, Nutlin-3 inhibited MDM2 but restored p53 in OSCC in a concentration-dependent manner. Meanwhile, Nutlin-3 suppressed the proliferation, clone formation, migration, invasion and epithelial-mesenchymal transition of SCC-9 cells and both boosted the apoptosis. In addition, Nutlin-3 caused a reduced cell viability and an elevated cell apoptosis rate in cisplatin-treated SCC-9 cells, indicating that Nutlin-3 enhanced cisplatin chemosensitivity in OSCC cells. Taken together, Nutlin-3 may suppress tumorigenesis and progression of OSCC and enhance chemosensitivity to cisplatin in OSCC.

IMMUNOHISTOCHEMICAL EXPRESSION OF P53 AND CYCLIN D1 IN SQUAMOUS CELL CARCINOMAAND EPITHELIAL HYPERPLASIA OF ORAL MUCOSA.

Oral cancer is among the top three types of cancers in India. Most invasive oral carcinomas are preceded by a pre-invasive stage, that may last for many years. . Understanding the molecular mechanisms involved in the initiation and progression to malignancy of oral cancer will help to improve its prognosis and in the elaboration of new forms of treatment. The most common genetic alterations, include gene amplication and overexpression of oncogenes such as myc, erbB-2, Epidermal Growth Factor Receptor (EGFR), Cyclin D1 and mutations, deletions and hypermethylation leading to p16 and p53 tumor suppressor gene inactivation. There still remains the problem of differentiating epitheliomatous hyperplasia from squamous cell carcinoma (SCC) especially on biopsies. AIMS: 1. To study and evaluate the expression of p53 and Cyclin D1 in oral SCC and epithelial hyperplasia. 2. To correlate the expression of p53 and Cyclin D1 in different grades of oral SCC. SETTINGS AND DESIGN:Cross-sectional study conducted over a period of 18 months. METHODS AND MATERIAL: 30 cases (n=30) of oral squamous cell carcinoma & 30 cases (n=30) of epithelial hyperplasia diagnosed on H & E were included in this study. All these cases of oral SCC were further classied into different histological grades according to BRODERS' HISTOLOGICALGRADE. STATISTICAL ANALYSIS: The data was collected and the association between different groups was analysed by using Chi square test and quantitative variables were compared using Independent Ttest/Mann-Whitney Test (when the data sets were not normally distributed) between the two groups and ANOVA/Kruskal Wallis test between three groups. Ap value of ≤0.05 was considered statistically signicant. RESULTS: There was a signicant increase in the expression of p53 in oral SCC compared to epithelial hyperplasia. The results were statistically signicant (p value <0.0001). Similarly , Cyclin D1 also showed an increased expression in cases of SCC in contrast to epithelial hyperplasia (p value <0.0001). The expression of p53 signicantly increased with increase in grade of the tumor. The results being statistically signicant, p value=0.004. Similarly, poorly and moderately differentiated SCC also showed an increased expression of Cyclin D1 compared to well differentiated SCC (p value=0.03, statistically signicant). CONCLUSION: Thus the author concludes that the expression of both p53 and Cyclin D1 is increased in oral SCC compared to epithelial hyperplasia of oral mucosa and these markers can be used to differentiate between these two lesion especially on biopsy cases.

Relationship between p16 expression and prognosis in different anatomic subsites of OSCC.

p16 has often been found to be overexpressed in patients oral squamous cell carcinoma (OSCC), but its prognostic value between anatomic subsites is still unclear. The aim of this study was to investigate the diagnostic and prognostic values of p16 in OSCC originating from tongue, gingiva or buccal mucosa. A total of 147 OSCC patients with tumors arising from the tongue, gingiva or buccal mucosa were enrolled in this study. p16 expression was detected using immunohistochemistry (IHC), and the presence of HPV16 was determined by real-time PCR in p16 positive patients. The correlation of p16 expression with the clinical parameters was evaluated. Only one p16 positive patient with a cut off value of 25% and 75% was HPV16 positive. Although overall survival (OS), recurrence free survival (RFS) and metastasis free survival (MFS) had no significant differences between the p16 positive and negative patients, p16 negative patients (cut off value 25%) had more RFS in the buccal mucosa cancer (p= 0.03) than the p16-positive patients. The prevalence of HPV16 in Chinese OSCC patients was low. p16 overexpression decoupled from HPV infection was not a prognostic marker for OSCC patients except for patients with the buccal mucosa cancer.

Overexpression of EGFR, COX2 and p53 in oral squamous cell carcinoma patients of Pakistan and correlation with prognosis

Abstract Background Oral squamous cell carcinoma (OSCC), the sixth leading cancer worldwide, ranks as the most common cancer in males, and the third most common in females in Pakistan. It is influenced by risk factors which are widely consumed in our population. The epidermal growth factor receptor (EGFR) is a tyrosine kinase receptor that is mutated and overexpressed in a variety of cancers. Cyclooxygenase 2 (COX2) is a rate-limiting enzyme that is upregulated in many cancers. It is involved in angiogenesis, apoptosis and metastasis of neoplasia. TP53 mutation and overexpression have been correlated with poor survival in many cancers including oral squamous cell carcinoma (OSCC). The aim of our study was to observe the expression of EGFR, COX2 and p53 in OSCC and correlate the expression with patient’s overall survival, and validate these markers for personalized therapy. Methods Formalin-fixed paraffin-embedded tissues of OSCC cases (n = 100) were used. Immunohistochemistry for EGFR, COX2 and p53 was performed using Dako monoclonal antibodies and EnVision system. Results There was a majority of males (55%) in our data set and the larger portion of patients was above 40 years of age (82%). Risk factor consumption was found in 73% of cases. EGFR overexpression was observed in 70%, COX2 in 55% and p53 in 67% of OSCC patients. Survival analysis revealed EGFR positive patients had markedly low overall survival (p = 0.098). Similarly, COX2 proved a good prognostic factor for patient survival (p = 0.013), while p53 overexpression was insignificant for survival (p = 0.107). Conclusions Our findings emphasize the role of EGFR, COX2 and p53 overexpression in OSCC patients. Molecular therapies targeted towards EGFR, COX2 and p53 may be used against Pakistani OSCC patients to improve prognosis. Legal entity responsible for the study Aga Khan University, Karachi, Pakistan. Funding Higher Education Commission, Pakistan. Disclosure All authors have declared no conflicts of interest.

The Expression and Correlation of iNOS and p53 in Oral Squamous Cell Carcinoma.

Oral squamous cell carcinoma (OSCC) is the most prevalent form of oral cancer. Inducible nitric oxide synthase (iNOS) and p53 are associated with a variety of human cancers, but their expression and interaction in OSCC have not been fully explored. In this study, we investigated the expression of iNOS and p53 in OSCC and their correlation with tumor development and prognosis. In addition, we explored the interaction of iNOS and p53 in OSCC. The expression of iNOS and p53 in OSCC was investigated using immunohistochemical method and their interaction was studied using RNAi technique. Our results showed that the expression of both iNOS and p53 was significantly correlated with tumor stages and pathological grade of OSCC (P < 0.05). In contrast, there was no correlation between iNOS and p53 expression and lymph node metastasis (P < 0.05). The OSCC survival rate was negatively associated with iNOS expression, but not with p53. A significant increase in the expression of the p53 was observed when iNOS expression was knocked down. The immunoexpression of iNOS is correlated with tumorigenesis and prognosis of OSCC and may serve as a prognostic marker.

DOX-MTX-NPs augment p53 mRNA expression in OSCC model in rat: effects of IV and oral routes.

Oral squamous cell carcinoma (OSCC) is the sixth most common malignancy worldwide. Cancer development and progression require inactivation of tumor suppressor genes and activation of proto-oncogenes. The well recognized mechanism of action demonstrated for chemotherapeutic agents is induction of apoptosis via reactivation of p53. In this context, we evaluate the efficacy of IV and oral routes of our novel PH and temperature sensitive doxorubicin-methotrexate-loaded nanoparticles (DOX-MTX NP) in affecting p53 profile in an OSCC rat model. In this study, 120 male rats were divided into 8 groups of 15 animals each. The new formulated DOX-MTX NP and free doxorubicin were IV and orally given to rats with 4-nitroquinoline-1- oxide induced OSCC. RESULTS showed that both DOX and DOX-MTX-NP caused significant increase in mRNA levels of P53 compared to the untreated group (p<0.000). With both DOX and DOX-MTX NP, the IV mode was more effective than the oral (gavage) route (p<0.000). Surprisingly, in oral mode, p53 mRNA was not affected in DOX treated groups (p>0.05), Nonetheless, both IV and oral administration of MTX-DOX NP showed superior activity (~3 fold) over free DOX in reactivation of p53 in OSCC (p<0.000). The effectiveness of oral route in group treated with nanodrug accounts for the enhanced bioavailability of nanoparticulated DOX- MTX compared to free DOX. Moreover, in treated groups, tumor stage was markedly related to the amount of p53 mRNA (p<0.05). Both oral and IV application of our novel nanodrug possesses superior activity over free DOX-in up-regulation of p53 in a OSCC model and this increase in p53 level associated with less aggressive tumors in our study. Although, impressive results obtained with IV form of nanodrug (-21 fold increase in p53 mRNA level) but both forms of nanodrug are effective in OSCC, with less toxicity normal cells.

The correlation between CpG methylation and protein expression of P16 in oral squamous cell carcinomas.

We examined the P16 expression by immunohistochemical stain and detected the methylation by methylation specific polymerase chain reaction (MSP) in 48 primary oral squamous cell carcinoma (SCC) tissues. The results showed that 20/48 (41.7%) of cancerous tissues had CpG methylation around the promoter region, but 8/48 (17%) of the nearby non-cancerous tissues also had CpG methylation, around the promoter region. The results from immunohistochemical studies showed that reduced and heterogeneous expression of P16 were found in the tissues, which had CpG methylation around the promoter region. In conclusion, the methylation of P16 in oral SCC occurs in pre-cancerous and cancerous stage, which results in decreasing or abolishing the P16 expression, which is heterogeneous in the cancer cells.