TP53 mutations and S-phase fraction but not DNA-ploidy are independent prognostic indicators in laryngeal squamous cell carcinoma

Value of p53 sequencing in the prognostication of head and neck cancer: a systematic review and meta-analysis

This review aimed to examine the relationship between TP53 mutational status, as determined by genomic sequencing, and survival in squamous cell carcinoma of the head and neck. The databases Medline, Embase, Web of Science (core collection), Scopus and Cochrane Library were searched from inception to April 2021 for studies assessing P53 status and survival. Qualitative analysis was carried out using the REMARK criteria. A meta-analyses was performed and statistical analysis was carried out to test the stability and reliability of results. Twenty-five studies met the inclusion criteria, of which fifteen provided enough data for quantitative evaluation. TP53 mutation was associated with worse overall survival (HR 1.75 [95% CI 1.45-2.10], p < 0.001), disease-specific survival (HR 4.23 [95% CI 1.19-15.06], p = 0.03), and disease-free survival (HR 1.80 [95% CI 1.28-2.53], p < 0.001). Qualitative assessment identified room for improvement and the pooled analysis of all anatomical subsites leads to heterogeneity that may erode the validity of the observed overall effect and its subsequent extrapolation and application to individual patients. Our systematic review and meta-analysis supports the utility of TP53 mutational as a prognostic factor for survival in head and neck squamous cell carcinoma. A well designed prospective, multi-centre trial is needed to definitively answer this question.

Impact of K-Ras Over-expression in Laryngeal Squamous Cell Carcinoma

BACKGROUND/AIM

Oncogene up-regulation combined with suppressor gene down-regulation is a crucial genetic combination that promotes cell neoplastic phenotype and progressively malignant transformation in solid malignancies, including laryngeal squamous cell carcinoma (LSCC). Among oncogenes, the Kirsten ras oncogene homolog (K-Ras) is involved in LSCC onset and progression.

PATIENTS AND METHODS

Sixty (n=60) primary LSCC tissue sections were analyzed by immunohistochemistry (IHC). Digital image analysis (DIA) was also implemented for measuring K-Ras protein expression levels.

RESULTS

High K-Ras protein expression levels were observed in 20/60 (33.3%) LSCC tissue sections, whereas the rest of the cases (n=40; 66.7%) demonstrated low expression. Overall K-Ras expression was borderline significantly associated to the grade of the examined malignancies (p=0.048), whereas no other strong statistical correlations were identified. A progressive K-Ras overexpression was observed in all grades of the examined cases.

CONCLUSION

K-Ras over expression is correlated to a progressive dedifferentiation in LSCC.

Genetic determinants in head and neck squamous cell carcinoma and their influence on global personalized medicine

While sequencing studies have provided an improved understanding of the genetic landscape of head and neck squamous cell carcinomas (HNSCC), there remains a significant lack of genetic data derived from non-Caucasian cohorts. Additionally, there is wide variation in HNSCC incidence and mortality worldwide both between and within various geographic regions. These epidemiologic differences are in part accounted for by varying exposure to environmental risk factors such as tobacco, alcohol, high risk human papilloma viruses and betel quid. However, inherent genetic factors may also play an important role in this variability. As limited sequencing data is available for many populations, the involvement of unique genetic factors in HNSCC pathogenesis from epidemiologically diverse groups is unknown. Here, we review current knowledge about the epidemiologic, environmental, and genetic variation in HNSCC cohorts globally and discuss future studies necessary to further our understanding of these differences. Long-term, a more complete understanding of the genetic drivers found in diverse HNSCC cohorts may help the development of personalized medicine protocols for patients with rare or complex genetic events.

Specific TP53 mutations predict aggressive phenotype in head and neck squamous cell carcinoma: a retrospective archival study

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy in the world in developed countries. Despite the intense research in the area of squamous cell carcinomas of head and neck (HNSCC), long-term survival rate has not changed significantly in this malignancy during recent decades.

METHODS

In this study, we focused on TP53 mutations in specific regions, including DNA-binding surface, to determine whether mutations at specific locations of TP53 could be used to help in setting up prognosis and response to therapy of head and neck squamous cell carcinoma patients. We analysed TP53 mutations in 46 HNSCC by PCR-SSCP and sequencing and characterized how different TP53 mutations affect the patient outcome.

RESULTS

Tumours containing TP53 mutations in DNA-binding regions (L2, L3 and LSH motif) had a significantly poorer prognosis and response to radiotherapy than tumours outside those regions. Disease-specific 5-year survival of patients with TP53 mutations affecting DNA contacts was 43.5% while it was 77.8% (p < 0.05) in patients with TP53 mutations in other residues not involved in DNA contact. Moreover, nodal metastasis were more prevalent (although not statistically significantly) with TP53 mutations in DNA-binding surface regions. We noticed that the patients with TP53 mutations in L3/LSH motifs had a significantly poorer response (11.4% responding) to radiation than the patients with a wild type p53 (48.6%) or TP53 mutations outside the DNA-binding regions (40%) (p < 0.05).

CONCLUSIONS

These data indicate that a TP53 mutation in L2, L3 or LSH is worth pursuing as a marker for predicting prognosis and response to radiation among HNSCC patients.

A systematic review of p53 as a prognostic factor of survival in squamous cell carcinoma of the four main anatomical subsites of the head and neck

OBJECTIVES

To summarize existing evidence about whether the presence of mutant or upregulated p53 is a prognostic factor for patients presenting with squamous cell carcinoma arising from the larynx, oropharynx, hypopharynx, or oral cavity.

METHOD

Relevant articles were identified using strict criteria for systematic searches. Associations between mutant or upregulated p53 versus wild-type or low/undetectable p53 in relation to overall survival and DFS were summarized by extracting or deriving hazard ratio (HR) estimates. Random-effects meta-analyses were used to account for between-study heterogeneity and to summarize the effect of p53 across studies.

RESULTS

The meta-analyses gave a statistically significant pooled HR for overall survival in oral cavity [pooled HR, 1.48; 95% confidence interval, (95% CI), 1.03-2.11], and for disease-free survival in oral cavity (pooled HR, 1.47; 95% CI, 1.12-1.93) and in oropharynx (pooled HR, 0.45; 95% CI, 0.27-0.73). Despite attempts to limit it, between-study heterogeneity was large in the majority of meta-analyses and the prognostic value of p53 was generally inconsistent and inconclusive across studies.

CONCLUSION

The meta-analysis results highlight that current evidence about the prognostic value of p53 in patients with squamous cell carcinoma of the head and neck is inconclusive. Large heterogeneity exists across studies in study-level and patient-level characteristics, making it difficult to ascertain a clear picture. Future studies are required in which p53 expression is investigated in a more standardized and biologically informative manner. In particular, prospectively planned individual patient data meta-analyses are needed to establish the prognostic importance of p53 for specific subgroups of patients undergoing specific treatments.

Heterogeneity of DNA content in laryngeal squamous cell carcinoma in relation to histopathological variables

CONCLUSION

Multivariate analysis showed age, lymph node status, proliferative index in transformation border, and DNA index in the center of laryngeal squamous cell carcinoma to be significant predictors for survival. By accessing distinctive areas of the tumor we were able to reduce the impact of intratumoral heterogeneity on prognostic factors.

OBJECTIVES

Laryngeal carcinomas are characterized by considerable histological variation within the tumor. The possible effects of this morphological heterogeneity on the estimation of tumor DNA content were investigated.

MATERIALS AND METHODS

We analyzed 92 cases of archived, paraffin-embedded laryngeal carcinoma. For each tumor, three different regions, defined microscopically (center of tumor, transformation border, invasive border), were analyzed. DNA content was measured by flow cytometry. Three parameters were evaluated: DNA ploidy, DNA index, and proliferative index.

RESULTS

DNA ploidy, DNA index, and proliferative index were higher in the tumor center than in the respective borders. Intratumoral differences in DNA ploidy were observed in 56 tumors (60.8%); DNA index heterogeneity was observed in 57.6% cases. Proliferative index varied greatly in morphologically different parts of the same carcinoma. DNA ploidy and DNA index of the transformation border correlated with tumor size and lymph node status. Proliferative index of the tumor center and of transformation border correlated with lymph node status, tumor size, and histological grade.

Arsenic trioxide induced the apoptosis of laryngeal cancer via down-regulation of survivin mRNA

OBJECTIVE

Arsenic trioxide (As(2)O(3)) is used clinically to treat acute promyelocytic leukemia and has activity in vitro against several solid tumor cell lines, where induction of differentiation and apoptosis are the prime effects. As a novel anticancer agent for treatment of solid cancers, As(2)O(3) is promising and the mechanism has been not still fully understood. Laryngeal squamous cell carcinoma (LSCC) is one common tumor in head and neck cancers. The objective of this study was to investigate the effects of As(2)O(3) on LSCC cell line HEP-2, and their possible involvement in As(2)O(3)-induced apoptosis.

METHODS

The cell viability was analyzed by MTT assay method and the morphological changes were observed by an inverted microscope and acridine orange (AO) staining. The caspase-3 activity was measured by a fluorophotometer. The expression of survivin mRNA was evaluated by RT-PCR.

RESULTS

In this study, we demonstrated an apoptotic effect of As(2)O(3) in LSCC cell line Hep-2. In Hep-2 cells, As(2)O(3) decreased the cell viability, inhibited the growth and proliferation, induced apoptosis and increased the activity of caspase-3 in a dose-dependent manner. And the expression of survivin mRNA was also decreased in a dose-dependent manner.

CONCLUSION

We concluded that As(2)O(3) induced the apoptosis of Hep-2 cells via down-regulating the expression of survivin mRNA.

Molecular differentiation of early and late stage laryngeal squamous cell carcinoma: an exploratory analysis

BACKGROUND

A current shortcoming in cancer prognostication and treatment is a lack of methods that adequately address the complexity and diversity of the disease. Prognostic marker systems based on single parameters have generally proven inadequate. Thus, multiparametric methods, which rely on many pieces of information, are ideally suited to the grouping of tumor subtypes and the identification of specific patterns of disease progression.

DESIGN

This study investigated, on an exploratory basis, whether genome wide alterations of loss and gain, using a panel of 122 gene probes (112 unique genes), discriminated between early stage (stage 1 and 2) and late stage (stage 3 and 4) laryngeal squamous cell carcinomas (LSCC). The LSCC cohort comprised 29 patients, 12 early and 17 late staged. Formalin-fixed LSCC DNA was interrogated by a genome wide candidate gene panel (122 genes) using the multiplex ligation-dependent probe amplification assay.

RESULTS

Statistical analysis employed the nonparametric Wilcoxon 2-sample test. Significant differences between tumor stages of early versus late were seen for the following genes: ERBB4, CASP2, RECQL4, and BCL7A. Loss of ERBB4 (P=0.045) and BCL7A (P=0.019) significantly discriminated between early and late stage LSCC. Gain of RECQL4 copy number (P=0.043) was associated with late LSCC. Gain of CASP2 (P=0.043) marked early LSCC, whereas loss was associated with late LSCC.

CONCLUSIONS

High-throughput genome wide approaches have the potential to yield discrete gene repertoires of early and late stage LSCC differentiation.