Alteration of p53 pathway in squamous cell carcinoma of the head and neck: impact on treatment outcome in patients treated with larynx preservation intent

Overview on Molecular Biomarkers for Laryngeal Cancer: Looking for New Answers to an Old Problem

Laryngeal squamous cell cancer (LSCC) accounts for almost 25-30% of all head and neck squamous cell cancers and is clustered according to the affected districts, as this determines distinct tendency to recur and metastasize. A major role for numerous genetic alterations in driving the onset and progression of this neoplasm is emerging. However, major efforts are still required for the identification of molecular markers useful for both early diagnosis and prognostic definition of LSCC that is still characterized by significant morbidity and mortality. Non-coding RNAs appear the most promising as they circulate in all the biological fluids allowing liquid biopsy determination, as well as due to their quick and characteristic modulation useful for non-invasive detection and monitoring of cancer. Other critical aspects are related to recent progress in circulating tumor cells and DNA detection, in metastatic status and chemo-refractoriness prediction, and in the functional interaction of LSCC with chronic inflammation and innate immunity. We review all these aspects taking into account the progress of the technologies in the field of next generation sequencing.

Cancer of the Larynx and Hypopharynx

The Radiation Therapy Oncology Group 91-11 trial and US Veterans Affairs trial revolutionized the way locally advanced laryngeal cancers are treated. Adjuvant therapies exist aimed toward laryngeal preservation using docetaxel, cisplatin, and fluorouracil. Cetuximab is a cornerstone of treatment due to the large role of epidermal growth factor receptor in laryngeal and hypopharyngeal carcinomas. In addition, the immune system is vital in the prevention of recurrence, and various immunomodulators against programmed cell death receptor 1 are being investigated. Multidisciplinary management of the patient with laryngeal and hypopharyngeal is key, as many vital functions are affected by this devastating disease.

Two miRNA prognostic signatures of head and neck squamous cell carcinoma: A bioinformatic analysis based on the TCGA dataset

MicroRNAs(miRNAs) are maladjusted in multifarious malignant tumor and can be considered as both carcinogens and tumor‐inhibiting factor. In the present study, we analyzed the miRNAs expression profiles and clinical information of 481 patients with head and neck squamous cell carcinoma (HNSCC) through the TCGA dataset to identify the prognostic miRNAs signature. A total of 114 significantly differentially expressed miRNAs (SDEMs) were identified, consisting of 60 up‐adjusted and 54 down‐adjusted miRNAs. The Kaplan‐Meier survival method identified the prognostic function of 2 miRNAs (miR‐4652‐5p and miR‐99a‐3P). Univariate and multivariate Cox regression analyses indicated that the 2 miRNAs were significant prognostic elements of HNSCC. Furthermore, bioinformatic analysis was conducted by means of 4 online gene predicted toolkits to recognize the target genes, and enrichment analysis was performed on the target genes by DAVID. The outcomes depicted that target genes were correlated with calcium, as well as cell proliferation, circadian entrainment, EGFR, PI3K‐Akt‐mTOR, and P53 signaling pathways. Finally, the PPI network was conducted in view of STRING database and Cytoscape. Eight hub genes were identified by CytoHubba and MCODE app, respectively, CBL, SKP1, H2AFX, HGF, POLR2F, UBE2I, VAMP2, and GNAI2 genes. As a result, we identified 2 miRNAs signatures, 8 hub genes, and significant signaling pathways for estimating the prognosis of HNSCC. In order to further explore the molecular mechanism of HNSCC occurrence and development, more comprehensive basic and clinical studies are needed.

Effects of microRNA-374 on proliferation, migration, invasion, and apoptosis of human SCC cells by targeting Gadd45a through P53 signaling pathway

The present study investigated the effects of microRNA-374 (miR-374) on human squamous cell carcinoma (SCC) cell proliferation, migration, invasion, and apoptosis through P53 signaling pathway by targeting growth arrest and DNA-damage-inducible protein 45 α (Gadd45a). Skin samples were collected from patients with skin SCC and normal skin samples. Expression of miR-374, Gadd45a, P53, P73, P16, c-myc, bcl-2, Bax, caspase-3, and caspase-9 were detected using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting. A431 and SCL-1 cells were divided into blank, negative control (NC), miR-374 mimics, miR374 inhibitors, siRNA–Gadd45a, and miR-374 inhibitors + siRNA–Gadd45a groups. Their proliferation, migration, invasion, cell cycle, and apoptosis were evaluated by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay, scratch test, Transwell assay, and flow cytometry. SCC skin tissues exhibited decreased expression of miR-374, P73, P16, Bax caspase-3 and caspase-9, and increased levels of Gadd45a, P53, c-myc, and Bcl-2 compared with the normal skin tissues. The miR-374 inhibitors group exhibited decreased expression of miR-374, P73, P16, Bax caspase-3 and caspase-9, and increased expression of Gadd45a, P53, c-myc, and Bcl-2, enhanced cell proliferation, migration, and invasion, and reduced apoptosis compared with the blank and NC groups; the miR-374 mimics group followed opposite trends. Compared with the blank and NC groups, the miR-374 inhibitors + siRNA–Gadd45a group showed decreased miR-374 level; the siRNA–Gadd45a group showed elevated levels of P73, P16, Bax, caspase-3 and caspase-9, decreased levels of Gadd45a, P53, c-myc, and Bcl-2, reduced cell proliferation, migration, and invasion, and accelerated apoptosis. miR-374 induces apoptosis and inhibits proliferation, migration, and invasion of SCC cells through P53 signaling pathway by down-regulating Gadd45a.

Cytokeratin-17 as a Potential Marker for Squamous Cell Carcinoma of the Larynx

To assess cytokeratin-17 (CK17) as an immunohistochemical marker for squamous cell carcinoma of the larynx, we stained 63 tissue samples from 63 consecutive patients who were believed or suspected to have squamous cell carcinoma of the larynx for CK17 and analyzed them by computerized histomorphometry. The mean staining intensity for CK17 was significantly stronger (p < .01) in cancerous cells, dysplasia, and normal epithelium proximal to the tumor than in distal normal epithelium and polyps. The percentage of stained area, within samples taken from a single patient, was significantly higher in malignancy and dysplasia as compared to distal normal epithelium and in malignancy as compared to dysplasia and proximal normal epithelium (p < .001). The integrated optical density was significantly higher in the malignant epithelium, dysplasia, polyps, and proximal normal epithelium than in distal normal epithelium (p < .0001). We conclude that CK17 is a highly sensitive and specific immunohistochemical marker for premalignant and malignant transformation in the larynx. Further investigation is warranted in order to assess the role of CK17 in determining safe resection borders.

Chromosomal aberrations and prognosis in patients with concomitant chemoradiotherapy for resected head and neck cancer

Although concomitant chemoradiotherapy (CCRT) has recently become a mainstay of a primary treatment modality in advanced head and neck squamous cell carcinoma (HNSCC), some of the patients experience CCRT failure. If we can predict the CCRT outcomes, we can reduce unnecessary CCRT avoiding risk of CCRT‑related complication. We aimed to identify genetic alteration markers related to treatment failure in HNSCC patients who underwent radical surgery and CCRT. Genome‑wide copy number alterations (CNAs) were analyzed in 18 HNSCC patients with (n=9) or without (n=9) recurrence using oligoarray‑comparative genomic hybridization and candidate CNAs were validated by quantitative RT‑PCR. A total of 15 recurrently altered regions (RARs) were identified in the 18 HNSCC cases. Among them, two RARs were significantly associated with CCRT‑failure: copy number gained RARs of 7p11.2 harboring EGFR (P=0.029) and 18p11.32 harboring TYMS gene (P=0.029). Three RARs (7p11.2, 9p21.3 and 18p11.32) were significantly associated with poor disease‑specific survival in univariate analysis, and 7p11.2 was consistently significant in the multivariate analysis (HR 40.68, P=0.003). In conclusion, we defined novel genomic alterations associated with CCRT‑failure: 7p11.2 (EGFR) and 18p11.32 (TYMS). Our results provide useful clues for the elucidation of the molecular pathogenesis of HNSCC and to predict CCRT‑failure.

Pretreatment tumor standardized uptake value as a prognostic factor in primary head and neck squamous cell carcinoma

Our objective was to conduct a systematic review and meta-analysis of studies assessing the diagnostic performance of primary tumor standardized uptake value (SUV) in head and neck squamous cell carcinoma (HNSCC), as measured by positron emission tomography. A systematic search of the indexed medical literature was conducted using appropriate keywords to identify relevant studies. Six articles were identified by searching electronic databases. A statistical analysis was performed with RevMan 4.2.2 software. SUV measurement and the SUV threshold for defining high SUV were studied dependently. For each publication, we first obtained an estimate of the relative risk (RR) for comparing patients with a low and those with a high SUV. Subsequently, we aggregated the individual RRs into a combined RR using the fixed-effects model to yield weighted mean pooled estimates with 95% confidence intervals (CIs). Publication bias was assessed with a funnel plot. A total of 6 clinical trials involving 453 patients were included in the meta-analysis. The combined RR from the 6 reports for local control was 0.72 (95% CI: 0.63-0.81). The funnel plot revealed symmetrical distribution, indicating no evidence of significant publication bias. The increase in the SUV of the primary tumor was found to be a poor prognostic marker for patients with HNSCC in the meta-analysis, which requires further confirmation in a meta-analysis based on individual patient data.

Pro-angiogenic effects of MDM2 through HIF-1α and NF-κB mediated mechanisms in LNCaP prostate cancer cells

Hypoxia stimulates several pathways that are critical to cancer cell growth and survival, including activation of vascular endothelial growth factor (VEGF) transcription. Overexpression of VEGF and the extent of neoangiogenesis are closely correlated with tumor development and cancer metastases. Recent studies suggest MDM2 as one of the major regulators of pro-angiogenic mechanisms. To assess the direct correlation of HIF-1α and NF-κB, and the actual mechanism of MDM2 involved in the control over VEGF transcription, we exposed the LNCaP and LNCaP-MST cells (MDM2 transfected) to hypoxia. Our experiments confirm that MDM2 activation can lead to significant decrease in the levels of p53 in MDM2 transfected LNCaP-MST cells than the wild-type LNCaP cells. The results further suggest that MDM2 can be a strong regulator of both p53 dependent and independent transcriptional activity. Similarly, an increased level of other transcription factors such as HIF-1α, P300, STAT3, pAKT and NF-κB was observed. As a point of convergence for many oncogenic signaling pathways, STAT3 is constitutively activated at high frequency in a wide diversity of cancers. Our results indicate that STAT3 can directly regulate VEGF expression that is controlled by MDM2. Furthermore, it is evident from our results that NF-κB may interfere with the transcriptional activity of p53, by downregulating its levels. On the other hand, several pro-angiogenic mechanisms, including VEGF transcription which is controlled by MDM2, seem to be mediated by NF-κB.

HPV: a factor in organ preservation for locally advanced larynx and hypopharynx cancer?

PURPOSE/OBJECTIVE

To assess the interaction of HPV/p16 status and therapy rendered in patients with locally advanced squamous cell carcinoma of the larynx and hypopharynx.

MATERIALS AND METHODS

Forty-seven consecutive patients receiving definitive treatment between 2009 and 2011 for locally advanced larynx or hypopharynx cancer with high-risk HPV and/or p16 testing performed were identified and retrospectively investigated. Overall survival (OS), disease-free survival (DFS), and local recurrence-free survival (LRFS) were assessed.

RESULTS

Of 47 evaluable patients, there were 38 (81%) with laryngeal and 9 (19%) with hypopharyngeal tumors, 13 (28%) of which were found to be either HPV or p16 positive. At a median follow-up of 24 months, comparing HPV/p16+ versus HPV/p16- patients, there was no difference in OS, DFS, or LRFS. There was an improvement in 2-year DFS (60% vs 100%, P=.03) and LRFS (80% vs 100%, P=.08), in HPV/p16+ patients treated with chemo/RT versus surgery. There was an improvement in 2-year DFS (100% vs 68%, P=.04) and LRFS (100% vs 72%, P=.05) in HPV/p16+ versus HPV/p16- patients who received chemo/RT.

CONCLUSIONS

Patients with HPV/p16+ tumors fared more favorably with chemo/RT than up-front surgery, with improvements in DFS and LRFS. In patients treated with the intent of organ preservation therapy, HPV/p16+ patients had no observed treatment failures. HPV/p16 status should be taken into account when considering organ preservation for locally advanced larynx and hypopharynx cancers.

Significance of CD133 expression in esophageal squamous cell carcinoma

Background

CD133 was recently reported to be a cancer stem cell marker and a prognostic marker for several tumors. However, few studies have investigated CD133 expression in esophageal squamous cell carcinoma (ESCC). Therefore, we examined whether CD133 could serve as a prognostic marker of ESCC and investigated the correlation between CD133 expression and the clinicopathological findings of ESCC patients and several markers.

Methods

We studied 86 ESCC patients who underwent curative surgery without neoadjuvant treatment at Tohoku University Hospital (Sendai, Japan) between January 2000 and December 2005. We analyzed tissue specimens by immunohistochemical staining for CD133, p53, p16, p27, murine double minute 2 (MDM2), Ki-67, and epidermal growth factor receptor (EGFR).

Results

Pathological tumor depth and tumor stage were significantly more advanced among CD133-negative patients than among CD133-positive patients. A log-rank test showed that CD133 immunoreactivity was significantly correlated with the overall survival of the patients (P = 0.049). However, multivariate analysis showed that it was not significantly correlated (P = 0.078). Moreover, CD133 was significantly positively correlated with p27 immunoreactivity (P = 0.0013) and tended to be positively correlated with p16 immunoreactivity (P = 0.057). In addition, p16 immunoreactivity was correlated with smoking history (P = 0.018), pathological lymph node status (P = 0.033), and lymphatic invasion (P = 0.018).

Conclusions

This study indicated that CD133 immunoreactivity is a good predictor of prognosis in ESCC patients. In addition, CD133 may play a role in the regulation of tumor cell cycle through p27 and p16 in ESCC. At present, it thus remains controversial whether CD133 expression is a valid prognostic marker for ESCC. To elucidate this relationship, further investigations are required.

Cyclophilin B expression is associated with in vitro radioresistance and clinical outcome after radiotherapy

The tools for predicting clinical outcome after radiotherapy are not yet optimal. To improve on this, we applied the COXEN informatics approach to in vitro radiation sensitivity data of transcriptionally profiled human cells and gene expression data from untreated head and neck squamous cell carcinoma (HNSCC) and bladder tumors to generate a multigene predictive model that is independent of histologic findings and reports on tumor radiosensitivity. The predictive ability of this 41-gene model was evaluated in patients with HNSCC and was found to stratify clinical outcome after radiotherapy. In contrast, this model was not useful in stratifying similar patients not treated with radiation. This led us to hypothesize that expression of some of the 41 genes contributes to tumor radioresistance and clinical recurrence. Hence, we evaluated the expression the 41 genes as a function of in vitro radioresistance in the NCI-60 cancer cell line panel and found cyclophilin B (PPIB), a peptidylprolyl isomerase and target of cyclosporine A (CsA), had the strongest direct correlation. Functional inhibition of PPIB by small interfering RNA depletion or CsA treatment leads to radiosensitization in cancer cells and reduced cellular DNA repair. Immunohistochemical evaluation of PPIB expression in patients with HNSCC was found to be associated with outcome after radiotherapy. This work demonstrates that a novel 41-gene expression model of radiation sensitivity developed in bladder cancer cell lines and human skin fibroblasts predicts clinical outcome after radiotherapy in head and neck cancer patients and identifies PPIB as a potential target for clinical radiosensitization.

Dynamic contrast-enhanced magnetic resonance imaging as a predictor of outcome in head-and-neck squamous cell carcinoma patients with nodal metastases

PURPOSE

Dynamic contrast-enhanced MRI (DCE-MRI) can provide information regarding tumor perfusion and permeability and has shown prognostic value in certain tumors types. The goal of this study was to assess the prognostic value of pretreatment DCE-MRI in head and neck squamous cell carcinoma (HNSCC) patients with nodal disease undergoing chemoradiation therapy or surgery.

METHODS AND MATERIALS

Seventy-four patients with histologically proven squamous cell carcinoma and neck nodal metastases were eligible for the study. Pretreatment DCE-MRI was performed on a 1.5T MRI. Clinical follow-up was a minimum of 12 months. DCE-MRI data were analyzed using the Tofts model. DCE-MRI parameters were related to treatment outcome (progression-free survival [PFS] and overall survival [OS]). Patients were grouped as no evidence of disease (NED), alive with disease (AWD), dead with disease (DOD), or dead of other causes (DOC). Prognostic significance was assessed using the log-rank test for single variables and Cox proportional hazards regression for combinations of variables.

RESULTS

At last clinical follow-up, for Stage III, all 12 patients were NED. For Stage IV, 43 patients were NED, 4 were AWD, 11 were DOD, and 4 were DOC. K(trans) is volume transfer constant. In a stepwise Cox regression, skewness of K(trans) (volume transfer constant) was the strongest predictor for Stage IV patients (PFS and OS: p <0.001).

CONCLUSION

Our study shows that skewness of K(trans) was the strongest predictor of PFS and OS in Stage IV HNSCC patients with nodal disease. This study suggests an important role for pretreatment DCE-MRI parameter K(trans) as a predictor of outcome in these patients.

Loss of MTBP expression is associated with reduced survival in a biomarker-defined subset of patients with squamous cell carcinoma of the head and neck

BACKGROUND

Recent genetic studies have implicated p53 mutation as a significant risk factor for therapeutic failure in squamous cell carcinoma of the head and neck (SCCHN). However, in a recent meta-analysis in the literature of p53 from major anatomical subsites (larynx, oral cavity, oropharynx/hypopharynx), associations between patient survival and p53 status were ambiguous.

METHODS

The authors examined a cohort of SCCHNs using a previously developed biomarker combination that likely predicts p53 status based on p53/MDM2 expression levels determined by immunohistochemistry (IHC). In addition, the authors generated and validated an antibody to MTBP (an MDM2 binding protein that alters p53/MDM2 homeostasis and may contribute to metastatic suppression) and have incorporated data for MTBP expression into the current analyses.

RESULTS

Analysis of expression data for p53 and MDM2 in 198 SCCHN patient samples revealed that the biomarker combination p53 + ve/MDM2-low (likely indicative of p53 mutation) was significantly associated with reduced overall survival (log-rank P = .035) and was an independent prognostic factor (P = .013; HR, 1.705; 95% CI, 1.12-2.60); thus, these data were compatible with earlier genetic analyses. By using IHC for p53 and MDM2 to dichotomize patients, the authors found that loss of MTBP expression was significantly associated with reduced survival (log-rank P = .004) and was an independent prognostic factor (P = .004; HR, 2.78; 95% CI, 1.39-5.54) in p53 + ve/MDM2-low patients.

CONCLUSIONS

These results represent the first examination of MTBP expression in human tissues and provide evidence for a p53 status-dependent role for MTBP in suppressing disease progression in SCCHN patients as well as confirming a role for p53 pathway function in delaying disease progression.

Pleural metastases as a unique entity with dismal outcome of head and neck squamous cell carcinoma

Once distant metastasis occurs, head and neck squamous cell carcinoma (HNSCC) patients generally have a poor prognosis with limited treatment options. A subgroup of patients who developed pleural metastases after curative treatment of localized HNSCC appeared to have worse outcomes. All patients from National Taiwan University Hospital who were diagnosed with localized HNSCC from January 1, 2000 to December 31, 2007 and developed distant metastases were included in this analysis. Medical records were reviewed. Patients with pleura as the first metastatic sites were compared to those with other first metastases for differences in basic demographics, time to distant metastasis (TTM) and overall survival (OS). A total of 198 patients were included, and 52 (26%) had pleural involvement at first diagnosis of distant metastases. Younger age at diagnosis (P=0.002) and buccal mucosa origin (P=0.006) were risk factors for developing pleural metastases. Patients with pleura as the first metastatic sites, compared to those with other first metastases, had significantly shorter TTM (median 7.5 vs. 11.1 months, P<0.001) and OS (median 9.6 vs. 16.5 months, P<0.001). By multivariate analysis, pleural metastases remained an independent predictor for shorter OS. In conclusion, patients with pleural metastases comprise a unique subgroup of HNSCC which rapidly develop distant metastases with poor prognosis.

Current potential and limitations of molecular diagnostic methods in head and neck cancer

Traditional diagnostic methods such as clinical assessment, histopathological examination and imaging techniques are limited in their capacity to provide information on prognosis and treatment choice of head and neck cancer. In recent years, molecular techniques have been developed that enabled us to get more insight into the molecular biological cellular pathways underlying tumor progression and metastasis. Correlation of these molecular changes with clinical events has been explored. However, consistently useful markers have not been identified yet, although many promising developments are in progress. It may be expected that in the near future, molecular markers will be useful for clinical purposes. In this paper, an overview will be given of the several molecular techniques that may have potential to be introduced in clinical practice in the management of head and neck squamous cell carcinoma.

Prognostic and predictive significance of p53, EGFr, Ki-67 in larynx preservation treatment

BACKGROUND

The optimal management of advanced laryngeal and hypopharyngeal cancers (L&HC) must involve consideration of both survival and functional effect of the given treatment approach. Despite over two decades of investigations of several treatment options, including surgery, radiotherapy, chemotherapy or some combinations thereof, little consensus exists as to which treatment offers the best survival, together with functional speech and swallowing.

AIM

To determine predictive and prognostic value of p53, EGFr, Ki-67 in patients with advanced laryngeal and hypopharyngeal cancer, treated with larynx preservation intent.

MATERIALS AND METHODS

Thirty-three patients received 2-3 cycles of induction chemotherapy (ICHT) consisting of cisplatin and fluoruracil and underwent subsequent radical radiotherapy. Immunohistochemical analyzes of p53, EGFr and Ki-67 were performed.

RESULTS

Response to ICHT was obtained in 24 patients (75%). Better response to ICHT was correlated only with EGFr expression (p = 0.04, RR = 1.91). The 5-year loco-regional control (LRC) and disease-specific survival (DSS) rates were 48% and 57%, respectively. The 5-year larynx preservation rate was 68% in responders to ICHT compared to 21% in non-responders (p = 0.02). It was also higher in patients without EGFr expression (but not significantly, p = 0.43).

CONCLUSION

Lack of EGFr expression is a favorable predictive factor for response to ICHT. Neither p53 nor Ki-67 have predictive and prognostic value in larynx preservation treatment.

Standardized uptake value is of prognostic value for outcome in head and neck squamous cell carcinoma

CONCLUSIONS

The literature-based meta-analysis confirmed that increased standardized uptake value (SUV) of the primary tumor is a poor prognostic factor in patients with head and neck squamous cell carcinoma (HNSCC), which should be further confirmed in a meta-analysis based on individual patient data.

OBJECTIVES

Primary tumor SUV, as measured by positron emission tomography (PET), has been studied as a potential prognostic factor for local control, disease-free survival, and overall survival. However, the limited sample sizes of the studies in the past led us to conduct a meta-analysis to improve the precision in estimating the effect of SUV on the prognosis of HNSCC.

METHODS

Eight articles were identified by searching electronic databases. Statistical analysis was performed with RevMan 4.2.2. SUV measurement and SUV threshold for defining high SUV were studied dependently. For each publication, we first obtained an estimate of the relative risk (RR) for comparing patients with a low and a high SUV. Subsequently, we aggregated the individual RRs into a combined RR, using a fixed-effects model. Publication bias was assessed with funnel plot.

RESULTS

We identified eight clinical trials dedicated to HNSCC. The combined RR from five reports for the local control was 0.71 (95% confidence interval [CI]: 0.63-0.81). The combined RR of the disease-free survival from six reports was 0.63 (95% CI: 0.54-0.73). Meanwhile, the combined RR of the overall survival from three reports was 0.57 (95% CI: 0.44-0.74). The funnel plot showed symmetrical distribution, indicating no evidence of substantial publication bias.

Biomarkers Predict p53 Gene Therapy Efficacy in Recurrent Squamous Cell Carcinoma of the Head and Neck

PURPOSE: Most recurrent squamous cell carcinomas of the head and neck have a dysfunctional p53 tumor suppressor pathway contributing to treatment resistance. We hypothesized that tumor p53 biomarkers may predict the efficacy of normal p53 delivered by gene therapy in these patients. EXPERIMENTAL DESIGN: Tumor p53 biomarkers were evaluated in 116 patients, including 29 treated with methotrexate in a phase III randomized controlled trial. Profiles favorable for p53 gene therapy efficacy were hypothesized to have either normal p53 gene sequences or low-level p53 protein expression, whereas unfavorable p53 inhibitor profiles were predicted to have high-level expression of mutated p53 that can inhibit normal p53 protein function. RESULTS: A statistically significant increase in tumor responses was observed for patients with favorable p53 efficacy profiles compared with those with unfavorable p53 inhibitor profiles [phase I/II trials: favorable (34 of 46, 74%) versus unfavorable (1 of 5, 20%), P = 0.0290; phase III trial: favorable (17 of 24, 71%) versus unfavorable (2 of 11, 18%), P = 0.0088]. In the phase III trial, there was statistically significant increased time to progression (TTP) and survival following p53 gene therapy in patients with favorable p53 profiles compared with unfavorable p53 inhibitor profiles (median TTP, 2.7 months versus 1.4 months, P = 0.0121; median survival, 7.2 months versus 2.7 months, P < 0.0001). In contrast, the biomarker profiles predictive of p53 gene therapy efficacy did not predict methotrexate response, TTP, or survival outcomes. CONCLUSIONS: These results indicate that tumor p53 biomarker profiles may predict p53 gene therapy efficacy in recurrent squamous cell carcinoma of the head and neck. (Clin Cancer Res 2009;15(24):7719-25).

Molecular markers predict outcome in squamous cell carcinoma of the head and neck after concomitant cisplatin-based chemoradiation

Not all patients with squamous cell carcinomas of the head and neck (HNSCC) benefit from concurrent cisplatin-based chemoradiation, but reliable predictive markers for outcome after chemoradiation are scarce. We have investigated potential prognostic biomarkers for outcome in a large group of patients. Ninety-one tumor biopsies taken from consecutive HNSCC patients were evaluated for protein expression on a tissue microarray. Using immunohistochemistry, 18 biomarkers, involved in various cellular pathways were investigated. Univariable and multivariable proportional hazard analyses were performed to investigate associations between each individual marker and outcome. In addition, the global test was used to test all variables simultaneously and selected combinations of markers for an overall association with local control. Univariable analysis showed statistically significant increased relative risks of RB, P16 and MRP2 for local control and MDR1 and HIF-1alpha for overall survival. MRP2, MDR1 and P16 levels were positively associated with outcome whereas RB and HIF-1alpha had a negative relationship. Using Goeman's global testing no combination of markers was identified that was associated with local control. Grouping the markers according to their function revealed an association between a combination of 3 markers (P16, P21 and P27) and outcome (p = 0.05) was found. In the multivariable analysis, MRP2 and RB remained significant independent predictive markers for local control. This study describes the prognostic value of biomarkers for the outcome in patients uniformly treated with concurrent chemoradiation. MRP2 and RB were found to be associated with outcome in patients treated with concurrent chemoradiation.

Genes involved in radiation therapy response in head and neck cancers

OBJECTIVES

This is a pilot study designed to identify gene expression profiles able to stratify head and neck squamous cell carcinoma (HNSCC) tumors that may or may not respond to chemoradiation or radiation therapy.

STUDY DESIGN

We prospectively evaluated 14 HNSCC specimens, arising from patients undergoing chemoradiotherapy or radiotherapy alone with curative intent. A complete response was assessed by clinical evaluation with no evidence of gross tumor after a 2-year follow-up period.

METHODS

Residual biopsy samples from eight complete responders (CR) and six nonresponders (NR) were evaluated by genome-wide gene expression profiling using HG-U133A 2.0 arrays. Univariate parametric t-tests with proportion of false discoveries controlled by multivariate permutation tests were used to identify genes with significantly different gene expression levels between CR and NR cases. Six different prediction algorithms were used to build gene predictor lists. Three representative genes showing 100% crossvalidation support after leave-one-out crossvalidation (LOOCV) were further validated using real-time QRT-PCR.

RESULTS

We identified 167 significant probe sets that discriminate between the two classes, which were used to build gene predictor lists. Thus, 142 probe sets showed an accuracy of prediction ranging from 93% to 100% across all six prediction algorithms. The genes represented by these 142 probe sets were further classified into different functional networks that included cellular development, cellular movement, and cancer.

CONCLUSIONS

The results presented herein offer encouraging preliminary data that may provide a basis for a more precise prognosis of HNSCC, as well as a molecular-based therapy decision for the management of these cancers.

Should there be more molecular staging of head and neck cancer to improve the choice of treatments and thereby improve survival?

PURPOSE OF REVIEW

Overall survival of head and neck squamous cell carcinoma patients on the whole has not dramatically improved in the last 30 years. One of the reasons is that tumour, node, metastasis classification is probably in some cases inadequate, since similar cases under a clinico-pathological point of view, may differ widely in prognosis. The most important reason for this is probably the extreme biological heterogeneity, which leads to a lack of consistency in treatment planning. The aim of the present review is to delineate the advances and the perspectives of clinical use of molecular characterization, which is an attempt to break through such molecular heterogeneity and to define, together with tumour, node, metastasis classification, homogeneous groups of patients for prognostic stratification and treatment selection.

RECENT FINDINGS

Among the markers evaluated in the last years, some have revealed particular promise. Epidermal growth factor receptor is probably the most reliable molecular marker at present, retaining its prognostic value independently from primary treatment. The p53 gene, the p53 protein being the main effector of DNA damage induced apoptosis, is probably the best predictor of radio/chemosensitivity.

SUMMARY

Even if clinical tumour, node, metastasis classification will probably retain its significance, it is now becoming possible, by molecular markers, to acquire biological information about host and tumour, to break through the above-cited molecular heterogeneity and eventually to optimize the choice of treatment.

Genetic abnormalities associated with chemoradiation resistance of head and neck squamous cell carcinoma

PURPOSE

To identify reliable predictors of chemoradiation resistance of advanced head and neck squamous cell carcinoma (HNSCC).

EXPERIMENTAL DESIGN

We did a matched-pair analysis of 20 chemoradiation-resistant and 20 sensitive HNSCCs, identified among a series of 104 consecutively treated cases. We compared the global DNA copy number profiles derived from comparative genomic hybridization analysis of both groups to identify genetic markers associated with chemoradiation resistance.

RESULTS

Although sensitive and resistant case groups were characterized by a similar total number of genetic aberrations, high-level amplifications were more frequent in resistant tumors. Resistant tumors were characterized by a different profile of genetic changes. Gains of 3q11-q13, 3q21-q26.1, and 6q22-q27 and losses of 3p11-pter and 4p11-pter were significantly associated with chemoradiation resistance. High-level amplifications unique to resistant cases involved the chromosomal regions 1p32, 3q24, 7p11.1, 7p11.2-12, 8p11.1, 8p11.1-12, 12q15, 13q21, 15q12, 18p11.3, and 18q11.

CONCLUSIONS

Sensitive and resistant HNSCCs are characterized by divergent genomic profiles. These profiles may be valuable as predictive markers of treatment failure.

High levels of the p53 inhibitor MDM4 in head and neck squamous carcinomas

The p53 tumor suppressor is mutated in most human tumors. MDM2, a well-known inhibitor of p53, is overexpressed in a large number of tumors, suggesting that increased levels of MDM2 also contribute to tumorigenesis. A novel p53 inhibitor, MDM4, was more recently identified. The role of MDM4 in cancer development is not well understood. We set out to examine the levels of MDM4 by immunohistochemistry in head and neck squamous carcinomas (HNSC) to ask whether high MDM4 levels could contribute to its development and progression. In addition, MDM2 and p53 levels were examined to identify overlapping expression patterns. MDM4 is present at high levels in 50% of HNSC. In addition, overexpression of MDM2 was detected in 80% of tumors, many of which were also positive for MDM4. A subset of tumors displayed high levels of all 3 proteins. Sequencing of the p53 gene revealed that tumors with positive immunoreactivity for MDM2 or MDM4, some of which also had high levels of p53, did not carry mutations in this gene. Thus, the detection of p53 by immunohistochemistry was not synonymous with the presence of p53 mutations. Expression of both MDM2 and MDM4 in tumors without p53 mutations strongly suggests that MDM2 and MDM4 inhibit the activity of this tumor suppressor in HNSC.

Identification of angiogenesis/metastases genes predicting chemoradiotherapy response in patients with laryngopharyngeal carcinoma

PURPOSE

To identify genes related to angiogenesis/metastasis that predict locoregional failure in patients with laryngopharyngeal cancer (LPC) undergoing chemoradiotherapy (CRT) treatment.

METHODS

Tumor tissue was collected and snap-frozen from 35 sequential patients with histologically confirmed LPC being treated with CRT. Gene expression analysis was performed using a novel cDNA array consisting of 277 genes functionally associated with angiogenesis (n = 152) and/or metastasis (n = 125). Locoregional response was correlated to the gene expression profiles to identify genes associated with outcome. These genes were internally validated by real-time reverse transcriptase polymerase chain reaction (RT-PCR) and validated externally by immunohistochemistry analysis on an independent set of patients.

RESULTS

Locoregional failure occurred in nine of 35 patients. Seventeen genes from the cDNA microarray correlated with locoregional failure (two-sample t test, P < .05). Seven genes were chosen for additional analysis based on the availability of antibodies for immunohistochemistry. Of these seven genes, real-time RT-PCR validated four genes: MDM2, VCAM-1, erbB2, and H-ras (Wilcoxon rank sum test, P = .008, .02, .04, and .04, respectively). External validation by immunohistochemistry confirmed MDM2 and erbB2 as being predictive of locoregional response. Controlling for stage of disease, positivity for MDM2 or erbB2 was an independent negative predictor of locoregional disease-free survival.

CONCLUSION

Genomic screening by cDNA microarray and validation internally by real-time RT-PCR and externally by immunohistochemistry have identified two genes (MDM2 and erbB2) as predictors of locoregional failure in LPC patients treated with CRT. The role of these genes in treatment selection and the functional basis for their activity in CRT response merit additional consideration.

The expression of p53-induced protein with death domain (Pidd) and apoptosis in oral squamous cell carcinoma

The Pidd (p53-induced protein with death domain) gene was shown to be induced by the tumour suppressor p53 and to mediate p53-dependent apoptosis in mouse and human cells, through interactions with components of both the mitochondrial and the death receptor signalling pathways. To study the role of Pidd in clinical tumours, we measured its expression by quantitative reverse transcription-PCR in microdissected oral squamous cell carcinomas (OSCC) with and without p53 mutation. Tumour cell apoptosis was assessed by in situ terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling. Tumour proliferation was assessed by immunohistochemical staining for the Ki-67 antigen. We found a wide range of Pidd expression among OSCC. Statistical analysis revealed an association between Pidd expression and apoptotic index (Mann-Whitney test, P<0.001), consistent with a role of Pidd in apoptosis in this tumour type. Furthermore, we showed a positive correlation between apoptotic index and proliferative index that has not been previously described for OSCC. There was no correlation between Pidd expression and the p53 mutation status of these tumours, suggesting that Pidd expression may be regulated by p53-independent mechanisms. Further characterisation of these molecular defects in the control of proliferation and apoptosis should help in developing treatments that target OSCC according to their biological properties.

Expression of p21WAF in salivary gland mucoepidermoid carcinoma and its relation to histologic grade

The biologic behavior and factors influencing the development of salivary gland mucoepidermoid carcinoma are not fully understood. Alteration of the cyclin-dependant kinase inhibitor p21(WAF) could cause uncontrolled proliferation leading to cancer. Thirty-five mucoepidermoid carcinomas were graded and immunohistochemically stained for p21(WAF). The percentage of positive tumor cells was determined using an eyepiece graticule and a computer-assisted image analyzer, which revealed 8.6% and 22.9% of the cases to be positive for p21(WAF), respectively. A statistically significant correlation was not observed between p21(WAF) and grading. Considering the absence of p21(WAF) expression in most mucoepidermoid carcinomas, it appears that the inhibitory effect of p21(WAF) on cell growth is removed in most cases. Given the lack of correlation with tumor grade, it is possible that the impact of p21(WAF) is in the earlier stages of tumorigenesis. A p53-independent pathway of p21(WAF) induction may exist for the small proportion of tumors that showed positivity.

Proteomic Signatures in Laryngeal Squamous Cell Carcinoma

Laryngeal cancer remains a worldwide health problem. The identification of biomarkers unique to laryngeal cancer may provide new insights into its pathogenesis, as well as provide potential targets for novel therapies and early detection. In order to identify potential biomarkers, we performed a proteomic analysis of laryngeal cancer specimens. Using two-dimensional differential in-gel electrophoresis and mass spectroscopy, protein expression profiles from two laryngeal carcinoma specimens and corresponding adjacent normal tissue were analyzed. The results of our analysis showed that the expression of a number of proteins was significantly altered in the tumor specimens when compared to matched normal controls. The differentially expressed proteins were identified, and they included stratifin, S100 calcium-binding protein A9, p21-ARC, stathmin, and enolase. With these findings, we have identified potential biomarkers which may contribute to the pathogenesis of laryngeal carcinoma, and which may be suitable as targets for novel therapeutic and/or diagnostic modalities.

Assessing interactions between mdm-2, p53, and bcl-2 as prognostic variables in muscle-invasive bladder cancer treated with neo-adjuvant chemotherapy followed by locoregional surgical treatment

BACKGROUND

Tumor proliferation and apoptosis may be influenced by the mdm-2 gene product, which can block the antiproliferative effects of p53. bcl-2, one of a family of related genes that regulates the apoptotic pathway, exhibits a negative influence. Both individual and cooperative effects of these gene products may affect the biological behavior of primary bladder cancers and long-term outcome to standard therapy.

METHODS

This study retrospectively evaluated the association with survival of mdm-2, p53, and bcl-2 expression in 59 patients with muscle-invasive, node-negative transitional cell carcinoma (TCC) treated with neo-adjuvant chemotherapy followed by locoregional surgery. Each marker was defined as an altered phenotype if >or=20% malignant cells in the primary tumor exhibited staining; normal or minimal expression was defined as <20% cells exhibiting staining.

RESULTS

Altered mdm-2, p53, and bcl-2 expression was observed in 37%, 54%, and 46% of patients, respectively. In single marker analysis, altered p53 expression correlated with long-term survival (P = 0.05) but mdm-2 (P = 0.42) or bcl-2 (P = 0.17) did not. In the multiple-marker analysis, a prognostic index simultaneously assessing mdm-2, p53, and bcl-2 correlated with survival (P = 0.01). The 5-year survival for patients in which all markers were normally expressed was 54% compared with 25% in those with all three markers aberrantly expressed. Patients with aberrant expression of either one or two markers had an intermediate 5-year survival (49%). There was no association of molecular markers either alone or in combination with pathologic downstaging after neo-adjuvant chemotherapy.

CONCLUSION

The cooperative effects of phenotypes determined by mdm-2, p53, and bcl-2 expression may predict survival in patients with muscle-invasive TCC of the bladder.

Laryngeal preservation in head and neck cancer: multidisciplinary approach

Since the first total laryngectomy was undertaken, efforts have been made to avoid removing the entire larynx. For a long time, partial surgery and radiotherapy were the only options that could preserve the larynx. Development of active chemotherapy regimens has prompted an era of intensive clinical research. Induction chemotherapy followed by radiotherapy in patients with objective responses has been shown to allow conservation of the larynx in nearly two-thirds of individuals, without any effect on survival; concurrent chemoradiotherapy also provides high rates of laryngeal preservation, again without affecting survival; and induction chemotherapy followed by concurrent chemoradiotherapy is under investigation. In the meantime, partial open surgery and endoscopic carbon dioxide laser procedures are feasible in selected moderately advanced laryngopharyngeal cancers as an alternative to destructive surgery. Altered fractionation radiotherapy can also be used in management of these tumours, and targeted treatments have opened a new area of clinical research. Findings of basic research and modern imaging should provide useful approaches for selection of patients for various strategies.

Molecular markers of head and neck squamous cell carcinoma: promising signs in need of prospective evaluation

BACKGROUND

The aim of this article is to review recent developments in the biological understanding of head and neck squamous cell carcinomas.

METHODS AND RESULTS

We describe the markers according to their function and their prognostic or predictive roles. Some associations can be found between molecular markers and invasiveness, aggressiveness, degree of differentiation, and tumor stage, but only a few clinical studies have shown an impact on prognosis. In addition, despite an increasing number of articles relating to this topic, the small number of patients included in the studies reported reduces the clinical implications of these results. Few studies applied a more comprehensive molecular analysis approach, such as DNA microarrays or differential expression profiling by polymerase chain reaction, to identify a combination of markers that could be more informative than a single molecular marker.

CONCLUSION

Some progress has been made with respect to molecular markers and head and neck cancers. Translational and prospective, hypothesis-driven research must proceed with sufficient rigor to facilitate the clinical applicability of such results.

American Society of Clinical Oncology Clinical Practice Guideline for the Use of Larynx-Preservation Strategies in the Treatment of Laryngeal Cancer

Purpose

To develop a clinical practice guideline for treatment of laryngeal cancer with the intent of preserving the larynx (either the organ itself or its function). This guideline is intended for use by oncologists in the care of patients outside of clinical trials.

Methods

A multidisciplinary Expert Panel determined the clinical management questions to be addressed and reviewed the literature available through November 2005, with emphasis given to randomized controlled trials of site-specific disease. Survival, rate of larynx preservation, and toxicities were the principal outcomes assessed. The guideline underwent internal review and approval by the Panel, as well as external review by additional experts, members of the American Society of Clinical Oncology (ASCO) Health Services Committee, and the ASCO Board of Directors.

Results

Evidence supports the use of larynx-preservation approaches for appropriately selected patients without a compromise in survival; however, no larynx-preservation approach offers a survival advantage compared with total laryngectomy and adjuvant therapy with rehabilitation as indicated.

Recommendations

All patients with T1 or T2 laryngeal cancer, with rare exception, should be treated initially with intent to preserve the larynx. For most patients with T3 or T4 disease without tumor invasion through cartilage into soft tissues, a larynx-preservation approach is an appropriate, standard treatment option, and concurrent chemoradiotherapy therapy is the most widely applicable approach. To ensure an optimum outcome, special expertise and a multidisciplinary team are necessary, and the team should fully discuss with the patient the advantages and disadvantages of larynx-preservation options compared with treatments that include total laryngectomy.

Molecular markers in laryngeal squamous cell carcinoma: towards an integrated clinicobiological approach

Of the most frequent malignancies in the United States, cancers of the larynx and of the uterine corpus are the only ones not to show an increase in 5-year survival rates over the last 30 years. The increasing use of chemo- and radiotherapy and conservative surgery to preserve organs and their functions has probably led to a better quality of life in patients with laryngeal cancer, but has definitely failed to improve survival, which remains the primary aim. In our opinion, to reduce laryngeal cancer-related mortality, a change in clinical approach is required. We have reviewed the literature on the potential role of molecular markers in the clinical management of laryngeal cancer. We believe that some of the most significant biological markers might be integrated with the evaluation of behavioural risk factors, clinical TNM staging and histopathological grading for a novel clinicomolecular approach to laryngeal cancer. We foresee the use of the most promising biological markers in the phases of prevention, diagnosis, prognostic assessment and drug design.

Prognostic value of the epidermal growth factor receptor (EGRF) and p53 in advanced head and neck squamous cell carcinoma patients treated with induction chemotherapy

We measured the expression of the p53 nuclear protein and epidermal growth factor receptor (EGFR) in 46 biopsy samples from patients with advanced head and neck cancer treated with induction combination chemotherapy of 5-fluorouracil, cisplatin, and paclitaxel. Tumour expression of p53 protein was analysed with the monoclonal D07 antibody and EGFR with monoclonal H11 antibody. The overall response, defined as complete (CR) and partial response (PR) rates to treatment, was 88%. p53 positive staining was significantly more frequent in patients who did not respond to the induction treatment. EGFR expression failed to show any correlation with the response rate. Multivariate analysis indicated that a tumour location in the oral cavity together with p53 expression combined with moderate-to-high EGFR staining were independent prognostic factors of a shorter disease-free survival (DFS). Location of the tumour in the oral cavity and EGFR expression had independent prognostic value for overall survival (OS). We conclude that the EGFR status and an oral cavity location of the tumour have independent prognostic value in patients with advanced head and neck carcinoma treated with induction chemotherapy. The p53 status appears to be a determinant of the tumour chemo-sensitivity in advanced head and neck squamous cell carcinoma (HNSCC). The presence in the tumour of a p53-positive stain and moderate-to-high staining of EGFR is associated with a shorter DFS and time to treatment failure (TTF) probably reflecting a more aggressive tumour phenotype.

Neutral endopeptidase protein expression and prognosis in localized prostate cancer

PURPOSE

Neutral endopeptidase (NEP) is a cell-surface peptidase that inactivates neuropeptide growth factors implicated in prostate cancer progression. The clinical significance of decreased NEP expression observed in prostate cancer is unclear. We investigated whether decreased NEP expression in localized prostate cancers is associated with prostate-specific antigen (PSA) relapse after radical prostatectomy.

EXPERIMENTAL DESIGN

NEP expression patterns were examined by immunohistochemistry in 223 men, who underwent radical prostatectomy between 1990 and 2000 at the Veterans Administration Medical Center (New York, NY) with available representative tissues and adequate follow up. We also examined whether hypermethylation of the NEP promoter contributes to down-regulation of NEP protein expression in a subset of patients that showed decreased NEP expression (n = 22).

RESULTS

Three patterns of NEP expression were observed: (a) membranous expression similar to benign prostate epithelium (n = 82; 37%); (b) complete loss of NEP expression in prostate cancer compared with adjacent benign prostate glands (n = 105; 47%); and (c) heterogeneous NEP expression (n = 36; 16%). In a multivariate analysis, complete loss of NEP expression was associated with PSA relapse after controlling for grade, stage, pretreatment PSA, and race simultaneously (hazard ratio, 1.99; 95% confidence interval, 1.13-3.52; two-sided chi(2) P = 0.017). In addition, DNA hypermethylation of the NEP promoter was frequently (73%) identified in a subset of 22 of cases that showed decreased NEP expression.

CONCLUSION

Our data suggest that decreased NEP expression might contribute to progression of localized prostate cancer after surgery. Data also suggest that methylation is an important mechanism of NEP protein silencing. Larger prospective studies are required for confirmation.

Cyclin A as a Predictive Factor for Chemotherapy Response in Advanced Head and Neck Cancer

PURPOSE

Overall survival of head and neck squamous cell cancer (HNSCC) patients has not improved despite advances in our understanding of the biology and molecular features of this disease. In particular, patients with advanced HNSCC have the poorest prognosis. To understand more about the contribution of cell cycle alterations to HNSCC development and their possible value in predicting prognosis and response to chemotherapy, we evaluated the levels of proteins involved in cell cycle control in patients diagnosed with advanced HNSCC.

EXPERIMENTAL DESIGN

A tissue microarray was made with 122 HNSCC specimens obtained from biopsy material. Protein expression was evaluated by immunohistochemistry and correlated with clinical and pathological characteristics.

RESULTS

Multiple alterations at various checkpoints of cell cycle progression were observed. Loss of P16 protein was less common in oropharyngeal tumors than at other HNSCC locations (P = 0.02). Evaluation of the simultaneous expression of different proteins highlighted direct correlations (P < 0.05) such as that of the cyclin-dependent kinases with their cyclin-partners, and the Ki-67 protein with cyclin-dependent kinases 1, cyclin A (CA) and cyclin B1. Median overall survival and time-to-progression were longer in patients with CA-expressing tumors (not reached versus 34.4 months, P = 0.02) and (47.3 versus 14.6 months, P = 0.006), respectively. Moreover, expression of CA in tumors predicted a better response to chemotherapy. Positive expression of cyclin E in tumors was also associated with an increased median time-to-progression (14.6 versus 25.8 months, P = 0.04). Finally, patients with cyclin D1-expressing tumors had shorter median overall survival (29.6 months versus not reached, P = 0.05) and shorter median time-to-progression (21.5 months versus not reached, P = 0.06). However, in a multivariate analysis a CA-negative-expressing tumor was the only independent poor prognostic factor in the entire cohort of HNSCC patients [odds ratio, 2.3; 95% confidence interval (CI) = 1.2-4.5; P = 0.01].

CONCLUSIONS

Our results provide detailed information on the molecular profile of cell cycle components in HNSCCs and identify CA-negative-expressing tumors as an independent marker of tumor progression and poor response to chemotherapy in patients diagnosed with advanced HNSCC.

Multistep laryngeal carcinogenesis helps our understanding of the field cancerisation phenomenon: a review

In this paper, we try to briefly review the most recent knowledge on head and neck cancer, and especially multistep laryngeal carcinogenesis, and to simply explain how this has modified our understanding of field cancerisation phenomenon. Experimental studies, made possible by the recent evolution of microdissection systems, have demonstrated that the "spatial progression"of the histopathological phenotype in the surroundings of malignant or premalignant head and neck lesions correlates with molecular progression. Such a "spatial progression" can be hypothesised to reflect temporal progression. The field cancerisation process has been divided into three phases, each with its own histological and molecular characteristics. Each of these phases may have clinical implications: detection and monitoring of fields may help cancer prevention (molecular epidemiology), early detection of recurrence (or, more exactly, of second field tumours (SFTs)) (molecular diagnostics) and prognostic prediction after treatment. This model appears plausible, especially in explaining the development of multiple primary tumours (MPTs) in adjacent head and neck mucosal regions, with peculiar clinical and prognostic implications: These tumours can be defined as multiple field tumours (SFTs). However, the model, in our opinion, does not convincingly explain the development of second primary tumours (SPTs) at more distant sites, such as the lung, colon and prostate.

The clinicopathological significance of p53 and p21 expression in squamous cell carcinoma of hypopharyngeal cancer

To evaluate the roles of p53 and p21 expression in the squamous cell carcinoma of hypopharyngeal cancer, we performed the immunohistochemical studies in 58 patients with hypopharyngeal cancer. We found significant correlation between a high expression of p53 and a histological grade of well differentiation, advanced tumor (T) and TNM stage. Furthermore, low expression of p21 correlated significantly with advanced TNM stage and positive nodal status. Cox's regression analysis revealed tumor stage and nodal status were the only prognostic factors for survival. Therefore, we concluded that p53 and p21 are useful markers in predicting some clinicopathological features in hypopharyngeal cancer.