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Introduction: Since the beginning of the 1990s, non-surgical radiochemotherapy treatment has become popular with the prospect of maintaining oncological results and preserving the organ in patients with advanced squamous cell carcinoma of the larynx and hypopharynx. However, subsequent studies demonstrated increased recurrence and mortality after the non-surgical treatment became popular., Objective: To compare the oncological results of surgical and non-surgical treatments of patients with larynx and hypopharynx cancer and to evaluate the variables associated with disease recurrence., Method: This is a retrospective cohort study of 134 patients undergoing surgical (total or partial laryngectomy) or non-surgical (isolated radiotherapy, chemotherapy or induction chemotherapy followed by radiotherapy and chemotherapy) treatment, with 62 patients in the surgical group and 72 in the non-surgical group., Results: Disease-free survival rates were higher in the surgical group (81.7% vs. 62.2%; p=0.028), especially in III/IV stages (p=0.018), locally advanced tumors T3 and T4a (p=0.021) and N0/N1 cases (p=0.005). The presence of cervical lymph nodes, especially N2/N3, was considered a risk factor for disease recurrence in both groups (HR=11.82; 95CI 3.42-40.88; p<0.0001). Patients not undergoing surgical treatment were 3.8 times more likely to develop recurrence (HR=3.76; 95CI 1.27-11.14; p=0.039)., Conclusion: Patients with larynx or hypopharynx cancer non-surgically treated had a poorer disease-free survival, especially in cases with locally advanced tumors (T3 and T4a) and in which the neck was only slightly affected (N0/N1).

Understanding of the biology of oral squamous cell carcinoma (SCC) has not progressed significantly in the past 60 years, with 5-year survival remaining at approximately 50%. The epidemic of Human Papilloma Virus and its associated SCC warrants a renewed emphasis on fully understanding this disease. We previously used the 3-dimensional multicellular spheroid (MCS) model system to evaluate SCC behavior more accurately. In this study, we determined that SCC growth in MCS approximates epithelial to mesenchymal transition. Organization of an MCS requires the full-length β6 integrin subunit and its maintenance requires mitogen-activated protein kinase (MAPK). Limiting FYN kinase activation results in the down-regulation of E-cadherin, β-catenin and an increase in expression of N-cadherin and SNAIL. These results indicate that the microenvironment and growth patterns in an MCS are complex and require MAPK and FYN kinase., (Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)

Squamous cell carcinomas (SCC) make up 96% of all oral cancers. Most laboratory SCC studies grow cells as a monolayer, which does not accurately represent the disease in vivo. We used a more relevant multicellular spheroid (MCS) model to study this disease. The SCC9β6KDFyn cell line, which expresses full-length β6 and a kinase dead Fyn formed the largest MCS. Cell adhesive properties are dynamic and N-cadherin was increased in the largest MCS. c-Raf mediates the survival of tumor cells and was consistently expressed both in monolayers and in the MCS by SCC9β6D1 cells which lack the β6 cytoplasmic tail and, do not activate Fyn. SCC9β6KDFyn cells also express high levels of c-Raf when grown as spheroids in which Fyn suppression stimulates MCS formation. Tumor microenvironment and growth patterns modulate cell behavior and suppression of Fyn kinase may promote MCS growth., (Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)

Prognosis for oral cancer patients has not improved in over 60 years due to invasion and recurrence. To understand the invasive behavior of this tumor, we evaluated the role of the αvβ6 integrin. Invasive oral SCC cells express the αvβ6 integrin, which contains an 11-amino-acid extension on its β-subunit unique to the integrin family. We determined that this β6 cytoplasmic extension regulates the composition of the intermediate filament network and the organization of signaling structures called focal contacts. The auto-phosphorylation of FAK, which is localized to focal contacts, was also regulated by the β6-cytoplasmic tail, as were the transcription factors Notch and STAT3. Lastly, we also determined that activation of MAPK required the full-length β6 integrin. Together these results indicate that the signaling critical to epithelial-to-mesenchymal transition (EMT) is regulated by the β6 integrin cytoplasmic domain.

Squamous cell carcinoma (SCC) accounts for 96 percent of all intraoral malignancies. The five-year survival rate is 50 percent and has not improved in 60 years. During SCC progression, subsets of SCC cells undergo an epithelial-to-mesenchymal transition (EMT) to become highly invasive. The extracellular matrix metalloproteinase inducer (EMMPRIN) contributes to EMT by activating local matrix metalloproteinases (MMPs). In this study, we found that EMMPRIN modulates the invasive phenotype and may be a potential therapeutic target.

This study shows that the expression of the extracellular matrix metalloproteinase inducer (EMMPRIN) in oral squamous cell carcinoma cells (SCC) depends upon activation of the Src Family kinaseFyn; and that EMMPRIN and β6 form a complex that requires active Fyn and the full length β6 integrin cytoplasmic domain. Fyn is also important for matrix remodeling as it regulates both matrix type 1 metalloproteinase (MT1-MMP) and tissue inhibitor of metalloproteinase-1 and -2 (TIMP1/2). The tumor promoter/suppressor caveolin-1, which associates with MT1-MMP, also requires FYN activation for expression. Lastly, EMMPRIN expression can act as a readout for the mitogen-activated protein kinase (MAPK) pathway, since when MAPK is blocked, so is the expression of EMMPRIN. In oral cancer, the activation of FYN occurs post β6 integrin ligand binding. That the activation of FYN drives EMMPRIN expression and several important pathways associated with invasive oral SCC is now demonstrated.

Oral squamous cell carcinoma (SCC) is an aggressive tumor with a poor 5-year survival rate. Oral SCC can undergo epithelial to mesenchymal transition (EMT). We previously showed that the epithelial integrin alphavbeta6 complexes with Fyn kinase in oral SCC to promote EMT. Using immunofluorescence microscopy and Western blotting, we evaluated whether the expression of specific markers of EMT were influenced by modulating serum concentration (ie. growth factors). The SCC cultures were grown under contrasting levels of serum. In low serum (1%), Fyn promoted EMT; whereas suppression of Fyn kinase promoted the epithelial phenotype. However, when the SCC cells were grown in 10% serum, activation of Fyn had the reverse effect. Lastly, cell migration was evaluated under low serum conditions (1% FBS). Activation of Fyn promoted SCC cell migration and its suppression thwarted SCC migration toward FN. These results indicate that the activation of Fyn kinase as well as local growth factor concentration modulate EMT in oral SCC.

Oral cancer is the sixth most frequent cancer worldwide. Prognosis for these patients remains poor. Recently, the epidermal growth factor receptor has been targeted as an adjunct to radiotherapy and surgery with limited success. The authors now present data suggesting that the alphanubeta6 integrin, which is a marker for aggressive oral cancer, may regulate epidermal growth factor receptor expression. The authors suggest perhaps targeting both alphanubeta6 and EGFR may provide additional benefits.

Oral squamous cell carcinoma (SCC) is composed of a heterogeneous population of cells which range anywhere from epithelial to mesenchymal in phenotype. Several oral cancer specimens with antibodies to TRA160, a marker of pluripotent cells, were screened. Compared with the well differentiated lesions, pluripotent cells were more numerous in specimens from poorly differentiated tumors. In vitro, the expression of TRA160 was much greater in invasive oral SCC9beta6 cells compared with the poorly invasive SCC9SN or SCC9beta6D1 cells, which express a truncated beta6. In vitro, pluripotent cells were instrumental in aggressively closing an experimental wound assay. Lastly, TRA-1-60+/beta6+ tumor cells which formed vascular-like structures in vivo were identified. SCC9beta6 cells formed interconnecting channels, whereas SCC9SN cells did not in an in vitro Matrigel angiogenesis assay. The results of this study clearly demonstrated the differential distribution of pluripotent stem cells in oral SCC and that the beta6 integrin may be an important regulatory component of the pluripotent phenotype.

In this study, we evaluated whether the forced expression of beta6 integrin would modulate the epithelial to mesenchymal transition (EMT). When the full length beta6 integrin was expressed in poorly invasive squamous cell carcinoma SCC9 cells, the resulting SCC9/6 cells acquired a fibroblast-like morphology, increased expression of the mesenchymal marker vimentin and reduced expression of the epithelial markers keratin and E-cadherin. SCC9beta6D1 cells, which express a truncated form of beta6 subunit lacking the C-terminal 11 amino acids (AA), retained their epithelial morphology and did not alter vimentin or E-cadherin expression. This suggests that the full-length beta6 subunit can induce EMT in oral SCC cells. We previously showed that expression of beta6 increases both MMP-3 activation and tenascin-C expression and we now show that both molecules are MEK dependent. These results also demonstrate that the terminal 11 AA of beta6 contain information important for establishing an epithelial to mesenchymal transition.

The extracellular matrix metalloproteinase inducer (EMMPRIN), found on the surface of many tumor cells, stimulates the production of matrix metalloproteinases (MMPs) by both fibroblasts and the tumor cells themselves. To evaluate its possible role as a tumor promoter, we first overexpressed EMMPRIN, by retroviral transduction, into poorly invasive squamous cell carcinoma (SCC) cells. Secondly, we knocked down its expression using small interfering RNA (siRNA) in invasive SCC cells. The cell lines were then re-evaluated for migration on fibronectin (FN). Overexpression of EMMPRIN, promoted motility, whereas the siRNA decreased migration. The MMP expression by these variant SCC cell lines was also manipulated by EMMPRIN. The expression of MMP-2, -3, and -9 coincided with the expression of EMMPRIN. Cocultures of SCC/peritumor fibroblasts (PTF) were used to investigate tenascin-C (TN-C) matrix deposition. The cocultures overexpressing EMMPRIN, deposited several fold greater levels of TN-C compared to the control cocultures. In addition, the siRNA cocultures deposited minimal amounts of TN-C. In the presence of the broad spectrum MMP inhibitor, GM6001, TN-C deposition by the EMMPRIN overexpressing cocultures was suppressed. Thus EMMPRIN regulates migration, MMP production by SCC cells and deposition of the TN-C matrix.

The integrin beta6 has been shown to promote invasion and experimental metastasis by oral squamous cell carcinoma (SCC). In this study, we demonstrate that the expression of beta6 by oral SCC9 cells increased activation of the UPA --> MMP3 --> MMP9 pathway. We also demonstrate that the deposition of fibronectin and tenascin-C matrices by SCC9beta6 cells and peritumor fibroblast cocultures is counter-regulated by the UPA --> MMP3 --> MMP9 pathway. Suppression of individual components of this pathway increased the deposition of fibronectin, but decreased tenascin-C matrix assembly by the cocultures. When the SCC9beta6/PTF cocultures were incubated with TGFbeta1, the deposition of fibronectin and tenascin-C as well as the activation of MMP3 and MMP9 was increased. These results indicate that MMP3, MMP9, and TGFbeta1 are important for the modulation, composition, and maintenance of the ECM in oral SCC.

We have previously shown that the integrin beta6 is neo-expressed in invasive oral squamous cell carcinoma (SCC) and is correlated with oral tumor progression. However, the mechanism by which the integrin beta6 promotes oral tumor progression is not well understood. The purpose of the present study was to determine whether integrin beta6 signaling activates Fyn and thus promotes oral squamous cell carcinoma progression. We analyzed the integrin beta6 signaling complex and investigated the function of these signaling molecules in oral SCC cells. We found that, upon ligation of the integrin beta6 with fibronectin, beta6 complexed with Fyn and activated it. The activation of Fyn recruited and activated focal adhesion kinase to this complex. This complex was necessary to activate Shc and to couple beta6 signaling to the Raf-ERK/MAPK pathway. This pathway transcriptionally activated the matrix metalloproteinase-3 gene and promoted oral SCC cell proliferation and experimental metastasis in vivo. These findings indicate that integrin beta6 signaling activates Fyn and thus promotes oral cancer progression.

Objective: Oral warts arising in human immunodeficiency virus (HIV) infection occasionally show marked epithelial dysplasia. However, anecdotal evidence suggests that they do not progress to oral squamous cell carcinoma (SCC). Therefore, we evaluated lesions for expression of proteins (tenascin-C, beta6 integrin, and matrix metalloproteinase-1[MMP1]) that have been identified as important in the invasive phase of oral SCC., Study Design: Twenty-two oral dysplastic warts from 22 patients and 5 oral SCCs were stained for human papillomavirus (HPV) antigen, proliferation protein Ki-67, tenascin-C, beta6, and MMP1 by immunohistochemical methods. For comparison, 5 nondysplastic warts each from HIV-positive and HIV-negative patients and 5 normal mucosa specimens were included. Sections were semiquantitatively assessed, and results were compared. Because MMP1 was the lowest or least expressed interface protein, MMP1 mRNA was quantitatively assessed from formalin-fixed paraffin-embedded tissue in selected cases with quantitative reverse transcription-polymerase chain reaction., Results: Twenty of 22 dysplastic warts stained positive for human papillomavirus common antigen, and all warts showed high proliferative fractions similar to SCCs. Tenascin-C and beta6 were variably expressed by the dysplastic warts but were consistently expressed at high levels in the SCCs. MMP1 protein levels were negative or low in 20 of 22 in dysplastic warts, but were elevated in 4 of 5 SCCs. MMP1 mRNA analysis indicated that message was low in 4 dysplastic warts and also suggested that protein translation was incomplete in 3 of the warts., Conclusion: We conclude that invasion-associated proteins are underexpressed in oral dysplastic warts in HIV-positive men. However, until these patients are followed for extended periods, the risk of development of SCC from oral dysplastic warts remains unknown.

Animal models of oral carcinogenesis have been developed but most use the hamster buccal pouch or rat oral mucosa. With completion of human and murine genome sequencing, the development of a mouse model of oral carcinogenesis may prove useful for future genomic studies of oral carcinogenesis. To achieve this objective, 30 SENCAR mice were initiated by brush application of palatal, buccal and tongue mucosa with 200 nmol 7,12-dimethylbenz[a]anthracene (DMBA) using 3 treatment regimens, and promoted by brush application with 5 nmol 12-O-tetradecanoylphorbol-13-acetate (TPA) for a total of 28 weeks. Alternatively, 5 mice were treated with 0.5% 4-nitroquinoline-1-oxide (4NQO) alone by brush application for 28 weeks. There were another 6 control mice treated with vehicle alone. The tumor samples were analyzed for the presence of H-ras codon 61 gene mutations using a mutant-allele-specific amplification-polymerase chain reaction (MASA-PCR) technique. The results showed that among the group of 24 mice initiated with DMBA for 2 or 6 weeks, a range of papilliferous lesions were seen on the buccal mucosa comprising papillomas, papillomas with dysplasia and 7 squamous cell carcinomas (SCC). In those 6 mice initiated with 1 week of DMBA, only papillomas developed. In the 5 mice treated with 4NQO, one developed papillomas with dysplasia and two had SCCs in the tongue mucosa but not the buccal mucosa. Both carcinogens induced codon 61 mutation of the H-ras gene at a high frequency. The results indicated that DMBA/TPA and 4NQO in SENCAR mice reliably produced preneoplastic and malignant oral cavity lesions, which resemble the multistages for human oral carcinogenesis, and targeted to site-specific zones of the oral mucosa, namely the buccal mucosa and tongue, respectively. These results show that SENCAR mice can be used as a unique model of oral carcinogenesis with the potential for detailed molecular studies of neoplastic progression to SCC.

Floor of the mouth squamous cell carcinomas exhibit many characteristics that suggest they represent a distinct biological subset within head and neck tumors. The features of preinvasive lateral intraepithelial spread, high rate of conversion of intraepithelial neoplasia to invasive carcinoma, and high incidence of occult metastases, suggest the importance of motility-associated proteins in the pathogenesis of these lesions. Two such proteins, tenascin and beta 6 integrin, are generally overexpressed in squamous carcinomas, and may play a central role in the invasive process of floor of the mouth lesions. The purpose of this study was to evaluate in situ and invasive squamous cell carcinomas from the floor of the mouth for the expression of tenascin and beta 6 integrin. Twenty lesions each of floor of the mouth in situ carcinomas and squamous cell carcinomas, and 10 normal controls were stained for tenascin and beta 6 using a standard immunohistochemical protocol for formalin-fixed specimens. Sections were assessed for staining intensity, pattern, and co-localization. Tenascin was highly expressed at the keratinocyte-connective tissue interface of both in situ and invasive carcinomas. beta 6 was expressed in basal keratinocytes of all in situ and invasive lesions, but was not evident in any of the control epithelia. There was no significant difference in staining of in situ and invasive carcinomas, but there was a significant difference in staining between these lesions and controls. Staining was colocalized in serial sections, supporting a receptor-ligand relationship. Both tenascin and beta 6 were weakly expressed in dysplastic areas adjacent to carcinomas suggesting that changes in the expression of these proteins occurs prior to the invasive phenotype. We conclude that tenascin and beta 6 are overexpressed in in situ and invasive floor of the mouth carcinomas, but that transgression of the basement membrane by neoplastic epithelial cells requires additional changes to the keratinocyte molecular profile.

Oral squamous cell carcinoma (SCC) is characterized by invasive growth and the propensity for distant metastasis. The expression of specific adhesion receptors promotes defined interactions with the specific components found within the extracellular matrix (ECM). We previously showed that the alpha v beta 6 fibronectin receptor is highly expressed in oral SCC. Here we forced expression of the beta 6 subunit into poorly invasive SCC9 cells to establish the SCC9 beta 6 cell line and compared these two cell lines in several independent assays. Whereas adhesion to fibronectin was unaffected by the expression of beta 6, migration on fibronectin and invasion through a reconstituted basement membrane (RBM) were both increased. Function-blocking antibodies to alpha v beta 6 (10D5) reduced both migration on fibronectin and invasion through an RBM, whereas anti-alpha 5 antibodies were effective only in suppressing migration on fibronectin, not invasion. Expression of beta 6 also promoted tumor growth and invasion in vivo and modulated fibronectin matrix deposition. When grown as a co-culture with SCC9 cells, peritumor fibroblasts (PTF) organized a dense fibronectin matrix. However, fibronectin matrix assembly was decreased in co-cultures of SCC9 beta 6 cells and PTF and this decrease was reversed by the addition of function-blocking anti-alpha v beta 6 antibodies. The expression of beta 6 also resulted in increased levels of matrix metalloproteinase 3. Addition of the general MMP inhibitor GM6001 to SCC9 beta 6/PTF co-cultures dramatically increased fibronectin matrix assembly in a similar fashion as incubation with anti-alpha v beta 6 antibodies. These results demonstrate that expression of beta 6 (1) increases oral SCC cell motility and growth in vitro and in vivo; (2) negatively affects fibronectin matrix assembly; and (3) stimulates the expression and activation of MMP3. We suggest that the integrin alpha v beta 6 is a key component of oral SCC invasion and metastasis through modulation of MMP-3 activity.

Introduction: Analysis of a series of works of world literature, discussing the accuracy of palpation and cervical lymph node imaging, highlighted the need to assess the method used in our teaching hospital. Objective: To evaluate the diagnostic accuracy of preoperative evaluation through palpation and CT cervical lymph nodes of patients with head and neck squamous cell carcinoma. Methods: We analyzed 398 patients with head and neck tumors. They compared the clinical stage assessed by palpation and CT scan of the neck with the data found by the anatomical and pathological analysis in the product of neck dissections conducted in order to determine the concordance rate between the two evaluations. Results: Of 398 patients included in the study, there was concordance rate of 83.6% between clinical staging considered negative and observed after emptying confirmed by pathological examination. It was noted that the accuracy of diagnosis of lymph node metastases in the preoperative period was 78.4% while the accuracy of agreement between the two staging was 69.1%. Conclusion: The use of imaging methods, particularly computed tomography associated with palpation, shows a significant increase in the diagnostic capacity of lymph node metastases. [ABSTRACT FROM AUTHOR]

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Copyright of Revista Brasileira de Cirurgia de Cabeça e Pescoço is the property of Revista Brasileira de Cirurgia de Cabeca e Pescoco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)