Assessment of p53 functional activity in tumor cells and histologically normal mucosa from patients with head and neck squamous cell carcinoma

Occurrence of field cancerization in clinically normal oral mucosa: A systematic review and meta-analysis

OBJECTIVE

The purpose was to describe whether there are field cancerization (FC) indicators in clinically normal mucosa opposite to primary oral squamous cell carcinoma (OSCC).

METHODS

A search of the Cochrane Library, PubMed, Embase, Web of Science, Scopus, and Livivo databases was performed on June 12, 2022, which retrieved 152 records without duplicates. Studies that analyzed FC in biopsies in clinically normal tissue opposite to primary OSCC were included. The search was conducted under the PRISMA guideline and the protocol was registered in PROSPERO (CRD42017077125).

RESULTS

Eight articles with 302 patients were included, 192 men and 110 women, mean age 57.1 years. Most patients had deleterious habits. All studies performed histopathological confirmation of OSCC and biopsies were obtained the clinically normal mirror mucosa. The meta-analysis carried out with eight studies. The studies showed 57.3 % of cases with histopathological changes of clinically normal mucosa opposite to primary OSCC (Confidence interval 95 %, 0.443-0.703; heterogeneity: Q value 18.715; I² 73.284 %; n = 205). p53 and Ki-67 immunohistochemical analysis may be predictive for detecting changes. There was p53 immunoexpression in 41.3 % of cases (p = 0.872) (n = 55), ki-67 immunoexpression (< 20 %) in 68 % (p = 0.001) (n = 97) and ki-67 immunoexpression (> 20 %) in 28.4 % of cases (p = 0.000) (n = 110).

CONCLUSIONS

The findings suggest that FC can occur, and there are histopathological changes in clinically normal tissue opposite to primary OSCC. Nevertheless, the review showed that more longitudinal studies on FC are needed to draw a conclusive indication of the occurrence of FC in oral tissues opposite to OSCC.

NIBAN1, Exploring its Roles in Cell Survival Under Stress Context

Cell survival must quickly activate specific mechanisms that enable to detect changes in the cellular microenvironment. The impact of these cell alteration has direct consequences on cellular homeostasis. Cellular stress, as well as its regulation and implication, has been studied in different pathologies. In this sense, the alteration in NIBAN1 expression seems to act in response to different cellular disturbances. Over the years, the knowledge of NIBAN1 functions has improved, demonstrating its important cell roles, favoring the cell survival under stress context. In response to the disturbances, NIBAN1 seems to be involved in the decision-making process between cell survival and death. The increase in NIBAN1 expression has been related to cellular mechanisms that seek to minimize the damage caused to cellular homeostasis. In this review, the main biological insights attributed to the NIBAN1 gene in different cellular contexts and its role as a mediator of cellular stress are discussed.

Clonal expansion in non-cancer tissues

Cancer is a clonal disorder derived from a single ancestor cell and its progenies that are positively selected by acquisition of 'driver mutations'. However, the evolution of positively selected clones does not necessarily imply the presence of cancer. On the contrary, it has become clear that expansion of these clones in phenotypically normal or non-cancer tissues is commonly seen in association with ageing and/or in response to environmental insults and chronic inflammation. Recent studies have reported expansion of clones harbouring mutations in cancer driver genes in the blood, skin, oesophagus, bronchus, liver, endometrium and bladder, where the expansion could be so extensive that tissues undergo remodelling of an almost entire tissue. The presence of common cancer driver mutations in normal tissues suggests a strong link to cancer development, providing an opportunity to understand early carcinogenic processes. Nevertheless, some driver mutations are unique to normal tissues or have a mutation frequency that is much higher in normal tissue than in cancer, indicating that the respective clones may not necessarily be destined for evolution to cancer but even negatively selected for carcinogenesis depending on the mutated gene. Moreover, tissues that are remodelled by genetically altered clones might define functionalities of aged tissues or modified inflammatory processes. In this Review, we provide an overview of major findings on clonal expansion in phenotypically normal or non-cancer tissues and discuss their biological significance not only in cancer development but also in ageing and inflammatory diseases.

An evolutionary perspective on field cancerization

Tumorigenesis begins long before the growth of a clinically detectable lesion and, indeed, even before any of the usual morphological correlates of pre-malignancy are recognizable. Field cancerization, which is the replacement of the normal cell population by a cancer-primed cell population that may show no morphological change, is now recognized to underlie the development of many types of cancer, including the common carcinomas of the lung, colon, skin, prostate and bladder. Field cancerization is the consequence of the evolution of somatic cells in the body that results in cells that carry some but not all phenotypes required for malignancy. Here, we review the evidence of field cancerization across organs and examine the biological mechanisms that drive the evolutionary process that results in field creation. We discuss the clinical implications, principally, how measurements of the cancerized field could improve cancer risk prediction in patients with pre-malignant disease.

Positive expression of NANOG, mutant p53, and CD44 is directly associated with clinicopathological features and poor prognosis of oral squamous cell carcinoma

Background

In order to predict long-term prognosis and define individual treatment modalities for patients with oral squamous cell carcinoma (OSCC), more reliable tumor biomarkers are needed during the pretreatment workup period. The present study aimed to identify more reliable immunohistochemical tumor prognostic markers in the pretreatment biopsy specimens of patients with OSCC.

Methods

We selected 57 patients who were diagnosed with primary OSCC through histopathological analysis. Pretreatment biopsy specimens were immunohistochemically analyzed for the transcription factor NANOG, cancer stem cell marker CD44, and mutant tumor protein 53 (mutant p53). The immunostaining patterns were assessed for their association with the clinicopathological features of OSCC and overall survival rates.

Results

Late tumor stage, positive neck node metastasis, and high-grade differentiation were associated with significantly poorer survival rates. Enhanced expression of NANOG and mutant p53 positivity were significantly associated with clinically late-stage tumors, positive neck node metastasis, histologically high-grade tumors, and poor overall survival rates. OSCCs with strong co-detection of NANOG and mutant p53 were linked to significantly lower survival rates than those with both weak NANOG expression and p53 negativity. Increased expression of CD44 had a limited correlation with unfavorable clinicopathological features.

Conclusion

High expression of NANOG and positive expression of mutant p53 in the pretreatment biopsy specimens of patients with OSCC were associated with poor survival rates and unfavorable clinicopathological features. These results demonstrate that NANOG, mutant p53, and CD44 could be used as immunohistochemical markers in the pretreatment specimens of OSCC. In particular, analysis for co-expression of NANOG and mutant p53 should be made highly available as a tool for prognosis and selecting individual treatment modalities.

Telomere shortening in mucosa surrounding the tumor: biosensor of field cancerization and prognostic marker of mucosal failure in head and neck squamous cell carcinoma

OBJECTIVES

The aim of the present study was to investigate the pattern of telomere length and telomerase expression in cancer tissues and the surrounding mucosa (SM), as markers of field cancerization and clinical outcome in patients successfully treated for with head and neck squamous cell carcinoma (HNSCC).

MATERIALS AND METHODS

This investigation was a prospective cohort study. Telomere length and levels of telomerase reverse transcriptase (TERT) transcripts were quantified by real-time PCR in cancer tissues and SM from 139 and 90 patients with HNSCC, respectively.

RESULTS

No correlation was found between age and telomere length in SM. Patients with short telomeres in SM had a higher risk of mucosal failure (adjusted HR=4.29). Patients with high TERT levels in cancer tissues had a higher risk of regional failure (HR=2.88), distant failure (HR=7.27), worse disease-specific survival (HR for related death=2.62) but not mucosal failure. High-risk patients having both short telomeres in SM and high levels of TERT in cancer showed a significantly lower overall survival (HR=2.46).

CONCLUSIONS

Overall these findings suggest that telomere shortening in SM is a marker of field cancerization and may precede reactivation of TERT. Short telomeres in SM are strongly prognostic of mucosal failure, whereas TERT levels in cancer tissues increase with the aggressiveness of the disease and are prognostic of tumor spread.

SLC23A2-05 (rs4987219) and KRAS-LCS6 (rs61764370) polymorphisms in patients with squamous cell carcinoma of the head and neck

Cancer is a genetic disease that is highly influenced by environmental factors. To determine the risk factors of squamous cell carcinoma of the head and neck, two polymorphisms, solute carrier family 23 member 2 (SLC23A2-05 [rs4987219]) and v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS)-LCS6 (rs61764370), and environmental factors, including smoking and alcohol consumption, were studied in a population. The present study included 165 males diagnosed with squamous cell carcinoma of the head and neck. The control group consisted of 230 healthy male subjects without cancer or a family history of cancer. The SLC23A2-05 and KRAS-LCS6 polymorphisms were analyzed by polymerase chain reaction followed by enzymatic digestion. All patients and healthy subjects were assessed with regard to their smoking habit and alcohol consumption as these are considered to be risk factors for cancer. The statistical analysis was performed using logistic regression, Fisher’s exact and χ² tests. Additional analyses were performed using the programs, multi-factor dimensionality reduction (MDR; version 2.0) and MDR permutation test (version 0.4.7), which consider all variables as risk factors simultaneously. The results of the present study demonstrate that the SLC23A2-05 and KRAS-LCS6 polymorphisms are not a risk factor for squamous cell carcinoma of the head and neck. In the same samples, the association of alcohol consumption (P<0.001) and smoking habit (P<0.001) with cancer presence was positive when each variable was considered individually. Concerning the environmental factors, a positive association of smoking habit and alcohol consumption with cancer, although not with ethnicity (ratio, 1.0244; testing balance accuracy, 0.8733; P<0.001) was identified using the MDR tool, which analyzed the variables and polymorphism genotypes simultaneously. In conclusion, in the present study, squamous cell carcinoma of the head and neck was highly affected by environmental factors when compared with the affect of SLC23A2-05 and KRAS-LCS6 polymorphisms.

Immunoprofiling of oral squamous cell carcinomas reveals high p63 and survivin expression

BACKGROUND

Cancer is a multifactorial disease composed of cells that show somatic mutations and epigenetic changes. The aim of this study was to investigate the expression of proteins involved in the development and maintenance of epithelia, cell cycle regulation, and apoptosis in human oral squamous cell carcinoma (OSCC) tissue samples.

METHODS

A tissue microarray containing 65 primary human OSCC specimens was immunolabeled for bcl-2, survivin, epidermal growth factor receptor (EGFR), p21, p53, p63, and cleaved caspase-3.

RESULTS

Samples were scored for percentage of positively stained tumor cells and staining intensity. A total immunostaining score was also calculated, using the product of percentage and intensity scores. All specimens showed high scores, > 75%, for p63 and survivin, and 75.4% of the specimens also presented high EGFR expression. All cases showed p53-positive cells. p21 showed a diffuse staining pattern. The percentage of cells positive for cleaved caspase-3 and bcl-2 was low.

CONCLUSIONS

The high frequency of tumor cells expressing p63 and survivin highlights the role of these proteins in the malignant transformation of oral epithelium. Collectively, our results suggest that p63 and survivin may constitute attractive targets for cancer therapy in patients with OSCC.

P53 immunohistochemical expression does not correlate with clinical features in 207 carcinomas of the oral cavity and in the head and neck region

OBJECTIVES

The present study aims to investigate the relevance of immunohistochemical p53 expression in carcinomas of the oral cavity and of the head and neck region. Long-term clinical and histopathological follow-up findings as well as HPV status are correlated with the results of this examination.

MATERIALS AND METHODS

Sections made from two tissue arrays composed of 222 oral squamous cell carcinomas and 427 squamous cell carcinomas of the head and neck region, respectively, were examined for p53 expression and Ki-67 index by means of immunohistochemistry. Correlation of long-term clinical findings of the patients and pathological features of tumours with laboratory results were examined statistically.

RESULTS

No significant correlation was found between the p53 immunohistochemical expression in the 207 oral carcinomas and features of the tumours and patient outcomes. There was no significant association between the Ki-67 labelling index and the p53 expression.

DISCUSSION

Our failure in detecting any association of the p53 immunohistochemical expression regardless of HPV status with clinical features of these tumours suggests it lacks a prognostic value for squamous cell carcinomas of the oral cavity.

CLINICAL RELEVANCE

The prognostic value of p53 immunostaining in oral squamous carcinoma is not clarified yet. In the present study, there is no impact on any prognostical item nor even a correlation with cell proliferation (Ki-67) regardless of HPV status.

AKT-dependent phosphorylation of Niban regulates nucleophosmin- and MDM2-mediated p53 stability and cell apoptosis

Although Niban is highly expressed in human cancer cells, the cellular functions of Niban remain largely unknown. We demonstrate here that ultraviolet irradiation induces phosphorylation of Niban at S602 by AKT, which increases the association of Niban with nucleophosmin and disassociation of nucleophosmin from the MDM2 complex. This leads to the promotion of MDM2-p53 interaction and subsequent p53 degradation, thereby providing an antiapoptotic effect. Conversely, depletion of or deficiency in Niban expression promotes stabilization of p53 with increased cell apoptosis. Our findings illustrate a pivotal role for AKT-mediated phosphorylation of Niban in protecting cells from genotoxic stress-induced cell apoptosis.