Eva Allonca

Distinctive clinicopathological associations of amplification of the cortactin gene at 11q13 in head and neck squamous cell carcinomas.

Amplification of the 11q13 region is a prevalent genetic alteration in head and neck squamous cell carcinoma (HNSCC). We investigated the clinical significance of cortactin (CTTN) and cyclin D1 (CCND1) amplification in both malignant transformation and tumour progression. CTTN and CCND1 amplification was analysed by differential and real‐time PCR in a prospective series of laryngeal/pharyngeal carcinomas and archival premalignant tissues. CTTN mRNA and protein expression were respectively determined by real‐time RT‐PCR and immunohistochemistry, and correlated with gene status. Molecular alterations were associated with clinicopathological parameters and disease outcome. CTTN and CCND1 amplifications were respectively found in 75 (37%) and 90 (45%) tumours. Both correlated with advanced disease; however, only CTTN amplification was associated with recurrence and reduced disease‐specific survival (p = 0.0022). Strikingly, CTTN amplification differentially influenced survival depending on tumour site (p = 0.0001 larynx versus p = 0.68 pharynx) and was an independent predictor of reduced survival in the larynx (p = 0.04). CCND1 amplification was detected in early tumourigenesis and increased with the severity of dysplasia. Importantly, CTTN amplification was only found in high‐grade dysplasias that progressed to invasive carcinoma. CTTN gene status strongly correlated with mRNA and protein expression. Furthermore, CTTN overexpression correlated significantly with reduced disease‐specific survival (p = 0.018). Taken together, these data indicate that CTTN may serve as a valuable biomarker to identify patients with laryngeal tumours at high risk of recurrence and poor outcome. Copyright

Down-regulation of annexin A1 and A2 protein expression in intestinal-type sinonasal adenocarcinomas.

Annexins are a structurally related family of calcium- and phospholipid-binding proteins that have been implicated in a broad range of molecular and cellular processes. The altered expression of individual annexins has been implicated in tumor development and progression. In this study the expression of annexin A1 and annexin A2 was studied by immunohistochemistry in intestinal-type sinonasal adenocarcinoma using a study set of 57 intestinal-type sinonasal adenocarcinomas represented on an intestinal-type sinonasal adenocarcinoma tissue microarray to assess its potential role in the pathogenesis of these tumors. Our results showed that annexin A1 expression was consistently lost in 52 (91%) intestinal-type sinonasal adenocarcinomas, as compared with the normal epithelium. The expression of annexin A2 was more heterogeneous, and only 19 (33%) cases showed annexin A2 negative expression. Annexin A2 expression was correlated with the histopathological type, being lower in the mucinous type (P = .022). The loss of annexin A2 expression correlated with a reduced survival in univariate analysis (P = .004). However, the impact of annexin A2 expression on patient survival could be an indirect consequence of its association with the histopathological type, since annexin A2 expression was not found to be an independent predictor in multivariate analyses. These results suggest that annexin A1 expression is frequently and commonly lost in intestinal-type sinonasal adenocarcinoma development. Annexin A2 expression is also reduced in intestinal-type sinonasal adenocarcinoma, and this loss of expression is associated to the more aggressive histopathological types.

Podoplanin expression in oral leukoplakia: Tumorigenic role

OBJECTIVES Recent studies have identified podoplanin, a mucin-type transmembrane glycoprotein, as a biomarker for oral cancer risk in patients with oral leukoplakia (OPL). The aim of this study was to investigate the potential association between podoplanin and the risk of malignant transformation of OPL with epithelial dysplasia. MATERIALS AND METHODS In this retrospective study, podoplanin immunoexpression was analyzed in 58 patients with oral leukoplakia that showed epithelial dysplasia. Lesions with podoplanin expression in the basal and suprabasal layers of oral epithelium at one area or showing suprabasal expression at two or more areas were considered as positive. Association between podoplanin expression and oral cancer development was analyzed. RESULTS Twenty-two of the 58 lesions (38%) were classified as podoplanin-positive, and the remaining 36 (62%) lesions were considered podoplanin-negative. The expression of podoplanin was correlated with the grade of dysplasia (p<0.0005), and with the risk of progression to oral cancer (p<0.0005). In multivariate survival analysis, only premalignant oral lesions displaying positive podoplanin expression showed a significantly increased risk of developing an oral squamous cell carcinoma (hazard ratio=8.738, p=0.007). CONCLUSION Podoplanin could be a valuable biomarker for risk assessment of malignant transformation in patients with OPL along with histological assessment.

Cortactin and Focal Adhesion Kinase as Predictors of Cancer Risk in Patients with Laryngeal Premalignancy

Novel markers are needed to accurately predict the risk of malignant transformation in laryngeal premalignancies. We therefore investigated the clinical significance of cortactin (CTTN) and focal adhesion kinase (FAK) during laryngeal tumorigenesis and their potential utility as cancer risk markers. CTTN and FAK protein expression and gene amplification were assessed in 82 patients with laryngeal dysplasia and correlated with clinicopathologic parameters and laryngeal cancer risk. Increased CTTN and FAK expression was found respectively in 41 (50%) and 40 (49%) of 82 laryngeal dysplasias; protein expression was maintained or further augmented in the corresponding patient-matched invasive tumors subsequently developed. CTTN and FAK/PTK2 gene amplifications were respectively detected in 10 (12%) and 26 (32%) laryngeal dysplasias. Both CTTN and FAK protein expression increased with the grade of dysplasia; however, CTTN and FAK expression but not histology correlated significantly with increased laryngeal cancer risk (P = 0.009 and P = 0.002, respectively). Patients carrying strong CTTN- or FAK-expressing dysplastic lesions experienced a significantly higher cancer incidence (P = 0.006 and P = 0.001, respectively; log-rank test). Furthermore, FAK expression was an independent predictor of laryngeal cancer development (HR = 3.706, 95% CI: 1.735–7.916; P = 0.001) and the combination of FAK and CTTN showed superior predictive value (HR = 5.042, 95% CI: 2.255–11.274; P < 0.001). Taken together, our findings support the involvement of CTTN and FAK in malignant transformation and provide original evidence for their potential clinical utility as biomarkers for the risk of developing laryngeal cancer. Cancer Prev Res; 4(8); 1333–41. ©2011 AACR.

Impact of PI3K/AKT/mTOR pathway activation on the prognosis of patients with head and neck squamous cell carcinomas

The PI3K/AKT/mTOR signaling pathway has emerged as one of the most frequently deregulated in head and neck squamous cell carcinomas (HNSCC). Numerous alterations of various upstream and downstream components have been described; however, their prognostic significance and impact on HNSCC patient survival remains to be established. This was addressed using an unbiased cohort of 93 consecutive and homogeneous surgically treated HNSCC patients and results confirmed in 432 HNSCC patients. Our findings reveal the high prevalence of S6 phosphorylation, a surrogate marker of mTORC1 activation, in HNSCC specimens (>70%) and, more importantly, demonstrate its relevance on clinical outcome. Phosphorylation of ribosomal protein S6 on either Ser235/236 or Ser240/244 was consistently and significantly correlated with favorable prognosis, although with differences depending on the tumor site. Thus, p-S6 expression was significantly correlated with better disease-specific survival specifically in the subgroup of laryngeal carcinoma patients (P< 0.001). In addition, multivariate regression models revealed p-S6 to be an inverse and independent predictor of lymph-node metastasis (P= 0.004) and distant metastasis (P= 0.006). Taken together, this study unveils an unprecedented correlation of mTOR activation with improved clinical outcome in patients with laryngeal carcinomas and uncovers the potential of p-S6 expression as a good prognostic biomarker and an inverse predictor of lymph node and distant metastases. These results should be of broad interest as immunohistochemical detection of p-S6 may help to stratify patients and guide treatment decisions.

Focal adhesion kinase overexpression: Correlation with lymph node metastasis and shorter survival in oral squamous cell carcinoma

Focal adhesion kinase (FAK) has been identified as a key mediator in tumor progression. The objective of this study was to determine the role of FAK as a predictor of neck node metastasis and poor prognosis in oral squamous cell carcinomas (OSCCs).

E-cadherin and β-catenin expression in well-differentiated and moderately-differentiated oral squamous cell carcinoma: relations with clinical variables

The aim of this study was to establish the expression and localisation of E-cadherin and β-catenin in oral squamous cell carcinomas (SCC) so that we could correlate the findings with prognostically-relevant clinicopathological variables. E-cadherin and β-catenin expression in normal oral mucosa and in oral squamous cell carcinomas were examined immunohistochemically, and their association with clinicopathological factors and prognosis were then analysed in 69 patients who had been operated on for oral SCC. E-cadherin expression was found in all 69 cases: in 11 cases (16%) it was weak; in 21 (30%) moderate, and in 37 (54%) high. β-Catenin expression was found in 64 cases (93%): in 18 cases (26%) cell-membrane expression was weak; in 26 (38%) it was moderate; in 19 (28%) it was high, and in one case (1%) there was cytoplasmic staining. No nuclear staining was detected. E-cadherin was significantly associated with histological grade (p=0.002) and alcohol consumption (p=0.05), and β-catenin was significantly associated with nodal stage (p=0.02), TNM stage (p=0.009), and E-cadherin expression (p=0.01). However, none of them were independent prognostic factors in the disease-specific survival analysis. E-cadherin is closely linked to β-catenin expression in oral SCC and to tumour differentiation. Alcohol consumption could increase the aggressiveness of SCC, leading to reduced expression of E-cadherin. β-catenin could be an early marker for the identification of occult metastases in patients with oral SCC.

Relevance of germline mutation screening in both familial and sporadic head and neck paraganglioma for early diagnosis and clinical management

Background: Head and neck paraganglioma (PGL) are benign tumors that can cause important direct or surgery induced morbidity. Almost all familial and 11–29% of sporadic PGL are caused by inactivating germline mutations in succinate dehydrogenase (SDH) genes. Our aim was to screen for such mutations and to evaluate clinical parameters as predictors of germline mutation. Methods: Seventy-four PGL patients were analyzed for germline mutations and large deletions in SDH genes, VHL and RET. Results were correlated to clinical characteristics including gender, age, tumor localization and multifocality. The surgical approach was evaluated in terms of tumor origin, sequelae and subsequent evolution. Results: Mutations in SDHB and SDHD were identified in equal proportion in 13/13 (100%) of familial and in 15/61 (25%) of sporadic cases. Familiarity, age ≤50 years and male gender were predictors of any germline mutation, while multifocality and carotid/vagal localization were indicative of SDHD mutation in particular. Conclusions: In contrast to other series, this cohort of Spanish patients showed many SDHB mutations. Sporadic cases with germline mutation are frequent and underline the importance of mutational screening of all PGL patients, allowing the identification of relatives at risk and the early diagnosis of the disease, reducing or avoiding morbidity.

Clinical significance of annexin A2 downregulation in oral squamous cell carcinoma.

The purpose of this study was to determine the expression of Annexin A2 (ANXA2) in normal oral epithelium and in oral carcinomas to correlate these findings with prognostically relevant variables.

Expression and clinical significance of the Kv3.4 potassium channel subunit in the development and progression of head and neck squamous cell carcinomas.

The concept of ion channels as membrane therapeutic targets and diagnostic/prognostic biomarkers has attracted growing attention. We therefore investigated the expression pattern and clinical significance of the Kv3.4 potassium channel subunit during the development and progression of head and neck squamous cell carcinomas (HNSCCs). KCNC4 mRNA levels were determined by real‐time RT‐PCR in both HNSCC tissue specimens and derived cell lines. Kv3.4 protein expression was evaluated by immunohistochemistry in paraffin‐embedded tissue specimens from 84 patients with laryngeal/pharyngeal squamous cell carcinomas and 67 patients with laryngeal dysplasias. Molecular alterations were correlated with clinicopathological parameters and patient outcome. Increased KCNC4 mRNA levels were found in 15 (54%) of 28 tumours, compared to the corresponding normal epithelia and varied mRNA levels were detected in 12 HNSCC‐derived cell lines analysed. Increased Kv3.4 protein expression was observed in 34 (40%) of 84 carcinomas and also at early stages of HNSCC tumourigenesis. Thus, 35 (52%) of 67 laryngeal lesions displayed Kv3.4‐positive staining in the dysplastic areas, whereas both stromal cells and normal adjacent epithelia exhibited negligible expression. No significant correlations were found between Kv3.4‐positive expression in HNSCC and clinical data; however, Kv3.4 expression tended to diminish in advanced‐stage tumours. Interestingly, patients carrying Kv3.4‐positive dysplasias experienced a significantly higher laryngeal cancer incidence than did those with negative lesions (p = 0.0209). In addition, functional studies using HNSCC cells revealed that inhibition of Kv3.4 expression by siRNA leads to the inhibition of cell proliferation via selective cell cycle arrest at the G2/M phase without affecting apoptosis. Collectively, these data demonstrate for the first time that Kv3.4 expression is frequently increased during HNSCC tumourigenesis and correlated significantly with a higher cancer risk. Our findings support a role for Kv3.4 in malignant transformation and provide original evidence for the potential clinical utility of Kv3.4 expression as a biomarker for cancer risk assessment. Copyright