Mode of tumor invasion in oral squamous cell carcinoma: improved grading based on immunohistochemical examination of extracellular matrices

Invasion-Associated Reorganization of Laminin 332 in Oral Squamous Cell Carcinomas: The Role of the Laminin γ2 Chain in Tumor Biology, Diagnosis, and Therapy

Simple Summary

The destructive growth of carcinomas is associated with crossing the border between the epithelial and the connective tissue parts of an organ. One component of this borderline, the basement membrane, is the heterotrimeric laminin 332, which mediates the adhesion of basal epithelial cells. This protein, in particular its gamma 2 chain, is fundamentally reorganized during tumor cell invasion. Specific deposition patterns of laminin 332 are also present in oral squamous cell carcinomas and have been shown to be of high diagnostic and predictive value. Furthermore, laminin 332 restructuring is associated with important tumor biological processes, e.g., stromal activation, the development of a motile phenotype, and tumor spreading. In this review, current knowledge in the field is summarized and the recommendation to consider laminin 332 as a promising grading and monitoring parameter and as a potential therapeutic target is discussed.

Abstract

Invasion of the connective tissue by carcinoma cells is accompanied by disintegration and reorganization of the hemidesmosomes, which connect the basement membrane to the basal epithelial cells. In terms of mediating the basement membrane, i.e., basal cell interactions, the heterotrimeric laminin 332 is the most important bridging molecule. Due to this distinct function, laminin 332, especially its gamma 2 chain, came into the focus of cancer research. Specific de novo synthesis and deposition patterns of laminin 332 are evident upon development and progression of oral squamous cell carcinomas (OSCCs). Loss from the basement membrane, cytoplasmic accumulation, and extracellular deposition are associated with crucial processes such as stromal activation and immune response, epithelial to mesenchymal transition, and tumor cell budding. In networks with components of the tumor microenvironment, altered expression of laminin 332 chains, proteolytic processing, and interaction with integrin receptors seem to promote cancer cell migration. Indeed, reorganization patterns are shown to have a high diagnostic and prognostic value. Here, we summarize the current knowledge on laminin 332 reorganization in OSCCs with special focus on its gamma 2 chain and provide, based on the current literature, evidence on its promising role as a grading and monitoring parameter and as a potential therapeutic target.

Omics data-driven analysis identifies laminin-integrin-mediated signaling pathway as a determinant for cell differentiation in oral squamous cell carcinoma

Background

In recent years, high-throughput omics technologies have been widely used globally to identify potential biomarkers and therapeutic targets in various cancers. However, apart from large consortiums such as The Cancer Genome Atlas, limited attempts have been made to mine existing datasets pertaining to cancers.

Methods and Results

In the current study, we used an omics data analysis approach wherein publicly available protein expression data were integrated to identify functionally important proteins that revealed consistent dysregulated expression in head and neck squamous cell carcinomas. Our analysis revealed members of the integrin family of proteins to be consistently altered in expression across disparate datasets. Additionally, through association evidence and network analysis, we also identified members of the laminin family to be significantly altered in head and neck cancers. Members of both integrin and laminin families are known to be involved in cell-extracellular matrix adhesion and have been implicated in tumor metastatic processes in several cancers. To this end, we carried out immunohistochemical analyses to validate the findings in a cohort (n = 50) of oral cancer cases. Laminin-111 expression (composed of LAMA1, LAMB1, and LAMC1) was found to correlate with cell differentiation in oral cancer, showing a gradual decrease from well differentiated to poorly differentiated cases.

Conclusion

This study serves as a proof-of-principle for the mining of multiple omics datasets coupled with selection of functionally important group of molecules to provide novel insights into tumorigenesis and cancer progression.

Study of the relationship between mononuclear inflammatory infiltrate and Ki-67 and basement membrane and extracellular matrix protein expression in radicular cysts

AIM

To evaluate the relationship between mononuclear inflammatory infiltrate and the expression of a proliferative immunomarker (Ki-67) as well as to evaluate basement membrane and extracellular matrix proteins (laminin and collagen type IV) in radicular cysts and dentigerous cysts (DC).

METHODOLOGY

Immunohistochemical analyses were performed in heavily inflamed radicular cysts (HIRC), slightly inflamed radicular cysts (SIRC) and DC (n = 20) using Ki-67 (Dako(®) , 1 : 50), anticollagen type IV (DBS(®) , 1 : 40) and antilaminin (DBS(®) , 1 : 20). The data were analysed using anova/Tukey's test (Ki-67) and Kruskal-Wallis/Dunn's test (collagen type IV and laminin) (P < 0.05).

RESULTS

The immunoexpression of Ki-67 was significantly greater in the SIRC group compared with the HIRC and DC (P = 0.0040). Likewise, the immunoexpression of collagen type IV in the basement membrane of the SIRC group was significantly more continuous (P = 0.0475) than in the HIRC group. DC had significantly less collagen type IV in extracellular matrix immunoexpression than HIRC and SIRC (P = 0.0246). Laminin was absent in the basement membrane in the SIRC and DC groups, and the extracellular matrix of the HIRC was weak and punctate.

CONCLUSION

The presence of inflammatory factors in the radicular cyst wall modified the expression of proliferation factors in the epithelial lining and the expression of collagen type IV and laminin in the basement membrane, but did not modify extracellular matrix behaviour in radicular cysts.

Secretome profiling of primary cells reveals that THBS2 is a salivary biomarker of oral cavity squamous cell carcinoma

Oral cavity squamous cell carcinoma (OSCC), which is a leading cause of cancer-related death worldwide, is frequently associated with poor prognosis and mortality. The discovery of body fluid-accessible biomarkers may help improve the detection of OSCC. In the present work, we established primary cell cultures derived from OSCC and adjacent noncancerous epithelium and performed comparative profiling of their secretomes. Using spectral counting-based label-free quantification, we found that 64 proteins were significantly higher in primary OSCC cells compared with primary adjacent noncancerous cells. We then retrieved the mRNA expression levels of these 64 proteins in oral cavity tumor and noncancerous tissues from public domain array-based transcriptome data sets and used this information to prioritize the biomarker candidates. We identified 19 candidates; among them, the protein levels of THBS2, UFD1L, and DNAJB11 were found to be elevated in OSCC tissues compared with adjacent noncancerous epithelia. Importantly, higher levels of THBS2 in OSCC tissues were associated with a higher overall pathological stage, positive perineural invasion, and a poorer prognosis. Moreover, the salivary levels of THBS2 in OSCC patients were elevated compared to those of noncancer controls. Our results collectively indicate that analysis of the primary cell secretome is a feasible strategy for biomarker identification, and that THBS2 is a potentially useful salivary marker for the detection of OSCC.

Selective inhibition of nuclear factor-κB by nuclear factor-κB essential modulator-binding domain peptide suppresses the metastasis of highly metastatic oral squamous cell carcinoma

Nuclear factor-κB (NF-κB) activation contributes to the development of metastasis, thus leading to a poor prognosis in many cancers, including OSCC. However, little in vivo experimental data are available about the effects of NF-κB inhibition on OSCC metastasis. OSCC sublines were established from a GFP-expressing parental cell line, GSAS, and designated GSAS/N3 and N5 according to the in vivo passage number after cervical lymph node metastasis by a serial orthotopic transplantation model. In vitro migration and invasion were assessed in these cells, and the NF-κB activities and expression of NF-κB-regulated metastasis-related molecules were also examined. In in vivo experiments, the metastasis and survival of tumor-engrafted mice were monitored. Furthermore, the effects of a selective NF-κB inhibitor, NEMO-binding domain (NBD) peptide, on metastasis in GSAS/N5-engrafted mice were assessed, and engrafted tongue tumors were immunohistochemically examined. Highly metastatic GSAS/N3 and N5 cells showed an enhanced NF-κB activity, thus contributing to increased migration, invasion, and a poor prognosis compared with the parent cells. Furthermore, the expression levels of NF-κB-regulated metastasis-related molecules, such as fibronectin, β1 integrin, MMP-1, -2, -9, and -14, and VEGF-C, were upregulated in the highly metastatic cells. The NBD peptide suppressed metastasis and tongue tumor growth in GSAS/N5-inoculated mice, and was accompanied by the downregulation of the NF-κB-regulated metastasis-related molecules in engrafted tongue tumors. Our results suggest that the selective inhibition of NF-κB activation by NBD peptide may provide an effective approach for the treatment of highly metastatic OSCC.

Immunohistochemical expression of basement membrane proteins of verrucous carcinoma of the oral mucosa

Squamous cell carcinoma (SCC) of the oral cavity is an extremely invasive tumour of stratified squamous epithelium that spreads throughout degradation of the basement membrane (BM) and extra-cellular matrix. Oral verrucous carcinoma (VC) is a rare low-grade variant of oral SCC that penetrates into the subepithelial connective tissue. It also has a different clinical behaviour from classical oral SCC. We investigated the immunohistochemical expression of laminin, laminin-5, collagen IV and fibronectin in VC, severe epithelial dysplasia (SED) and SCC in order to analyse if the pattern of these molecules expression contributes to the differences in the biological behaviour of these diseases. The staining pattern of laminin was less intensive in SCC compared with SED and VC, and collagen IV expression was increased in VC compared with SED. Discontinuities of laminin, collagen IV and fibronectin were more evident in SED than in VC. This study indicates that VC has a biological behaviour different from SED or SCC, observable by immunohistochemistry in the BM zone.

Mandibular invasion of squamous cell carcinoma: factors determining surgical resection of mandible using computerized tomography and histopathologic study

AIM

Carcinoma of the mandibular region can be considered as an important, distinct entity associated with special problems relating to diagnosis, evaluation of extension, planning of treatment, surgical techniques, treatment result and prognosis. The study was aimed to assess the accuracy of computerized tomography in demonstrating mandibular invasion, to assess the role of anatomic structures like cancellous spaces, the inferior alveolar nerve and periodontal spaces in spread of carcinomas in the mandible and to determine the spread of tumour within the mandible and the resection procedure to be carried.

MATERIALS AND METHODS

11 mandibular specimens which were resected for squamous cell carcinoma were examined clinically, radiographically and histopathologically. Computerized tomography 120 KV, 40 to 130ma, obtaining slices starting from the center of lesion to the clearance, of the bone involvement distally and proximal to the lesion with excellent soft tissue or cortical bone interface with bone enhancement mode was used as a principle investigating tool to assess the tumour penetration in the mandible which was confirmed by histopathologic sections.

RESULTS

A conditional probability test was conducted according to Bayes' theorem, and the results showed sensitivity 60% and specificity 77.8%, a false negative rate 40% and false positive rate 22.2%. A positive predictive value 69% and negative predicative value 70%.

CONCLUSION

In our study the factors to be taken into consideration in deciding the type of resection are the pattern of tumour infiltration, irradiated or non irradiated mandibles, presence or absence of dentition, the inferior alveolar nerve involvement and the periodontal space involvement. The computerized tomography has a significant role in detecting the involvement of tumour in the mandible with enhanced settings.

Enhanced interferon signaling pathway in oral cancer revealed by quantitative proteome analysis of microdissected specimens using 16O/18O labeling and integrated two-dimensional LC-ESI-MALDI tandem MS

Oral squamous cell carcinoma (OSCC) remains one of the most common cancers worldwide, and the mortality rate of this disease has increased in recent years. No molecular markers are available to assist with the early detection and therapeutic evaluation of OSCC; thus, identification of differentially expressed proteins may assist with the detection of potential disease markers and shed light on the molecular mechanisms of OSCC pathogenesis. We performed a multidimensional (16)O/(18)O proteomics analysis using an integrated ESI-ion trap and MALDI-TOF/TOF MS system and a computational data analysis pipeline to identify proteins that are differentially expressed in microdissected OSCC tumor cells relative to adjacent non-tumor epithelia. We identified 1233 unique proteins in microdissected oral squamous epithelia obtained from three pairs of OSCC specimens with a false discovery rate of <3%. Among these, 977 proteins were quantified between tumor and non-tumor cells. Our data revealed 80 dysregulated proteins (53 up-regulated and 27 down-regulated) when a 2.5-fold change was used as the threshold. Immunohistochemical staining and Western blot analyses were performed to confirm the overexpression of 12 up-regulated proteins in OSCC tissues. When the biological roles of 80 differentially expressed proteins were assessed via MetaCore analysis, the interferon (IFN) signaling pathway emerged as one of the most significantly altered pathways in OSCC. As many as 20% (10 of 53) of the up-regulated proteins belonged to the IFN-stimulated gene (ISG) family, including ubiquitin cross-reactive protein (UCRP)/ISG15. Using head-and-neck cancer tissue microarrays, we determined that UCRP is overexpressed in the majority of cheek and tongue cancers and in several cases of larynx cancer. In addition, we found that IFN-beta stimulates UCRP expression in oral cancer cells and enhances their motility in vitro. Our findings shed new light on OSCC pathogenesis and provide a basis for the future development of novel biomarkers.

Expression of basement membrane laminin in oral squamous cell carcinomas

The basement membrane is a dynamic structure that undergoes quantitative and qualitative changes during the progression of squamous cell carcinoma, which is essencially important in tumoral invasion and metastasis.

Aim

This study is aimed at investigating the behavior of the basement membrane in oral squamous cell carcinomas with different malignancy scores, which were obtained through the immunohistochemical expression of the laminin, a glycoprotein present in the basement membrane.

Study design

History cross-sectional cohort.

Material and method

Thirty-one cases of oral squamous cell carcinoma were subjected to histological grading of malignant tumors. The immunohistochemical expression of the laminin in lesions bearing different scores of malignancy was evaluated according to intensity and integrity, using the Streptavidin-Biotin complex method.

Results

We noticed significant differences in the media between intensity and continuity laminin expression in relation to different grades of malignancy.

Conclusion

Different expressions of laminin, a glycoprotein present in basement membranes were evident in oral cell carcinomas within different grades of histological malignancy.

Expressão da laminina na membrana basal em carcinoma escamocelular oral

A membrana basal é uma estrutura dinâmica que sofre modificações qualitativas e quantitativas durante a progressão do carcinoma escamocelular, e este processo é de fundamental importância na invasão neoplásica e metástase. OBJETIVO: O objetivo deste estudo foi investigar o comportamento da membrana basal em carcinomas escamocelulares de boca com diferentes graus de malignidade histológica através da expressão imuno-histoquímica da laminina. FORMA DE ESTUDO: Coorte histórica com corte transversal. MATERIAL E MÉTODO: Trinta e um casos de carcinoma escamocelular de boca foram submetidos à graduação histológica para tumores malignos. Através do método da streptavidina-biotina, foi verificada a expressão imuno-histoquímica da laminina em relação à sua intensidade e integridade nas lesões com diferentes graus de malignidade. RESULTADOS: Foram observadas diferenças estatisticamente significativas dos valores médios da intensidade e da continuidade de marcação da laminina em relação aos diferentes graus de malignidade. CONCLUSÃO: Ficou demonstrado que a laminina, uma glicoproteína presente na membrana basal, sofreu modificações diferenciadas em carcinomas escamocelulares de boca nos diferentes graus de malignidade histológica.

Expression of tumor-associated antigen RCAS1 and its possible involvement in immune evasion in oral squamous cell carcinoma

BACKGROUND

RCAS1 (receptor-binding cancer antigen expressed on SiSo cells) is known to induce apoptosis in its receptor-positive cells. The authors investigated RCAS1 expression in oral squamous cell carcinoma (SCC) and its association with the apoptosis of tumor-infiltrating lymphocytes (TILs).

METHODS

In 130 patients with oral SCC, the expression of RCAS1 in tumor cells was immunohistochemically examined and the apoptosis of TILs was examined by Terminal Deoxynucleotidyltransferase-mediated dUTP Nick End Labeling (TUNEL) staining.

RESULTS

RCAS1 was detected both on the cytoplasm and the membrane of tumor cells in 41 of 130 cases (31.5%). Focusing on the expression at the invasive front interacting with host immune cells, RCAS1 was detected in 22 of 130 cases (16.9%). The percentage of TUNEL-positive TILs in cases with RCAS1-positive SCCs was significantly higher than in cases with RCAS1-negative SCCs (P < 0.0001).

CONCLUSIONS

RCAS1 can be expressed on oral SCC cells and may be involved in the tumor escape from the host immune system by inducing the apoptosis of TILs.

Loss of intercellular adhesion activates a transition from low- to high-grade human squamous cell carcinoma

The relationship between loss of intercellular adhesion and the biologic properties of human squamous cell carcinoma is not well understood. We investigated how abrogation of E-cadherin-mediated adhesion influenced the behavior and phenotype of squamous cell carcinoma in 3D human tissues. Cell-cell adhesion was disrupted in early-stage epithelial tumor cells (HaCaT-II-4) through expression of a dominant-negative form of E-cadherin (H-2Kd-Ecad). Three-dimensional human tissue constructs harboring either H-2Kd-Ecad-expressing or control II-4 cells (pBabe, H-2Kd-EcadDeltaC25) were cultured at an air-liquid interface for 8 days and transplanted to nude mice; tumor phenotype was analyzed 2 days and 2 and 4 weeks later. H-2Kd-Ecad-expressing tumors demonstrated a switch to a high-grade aggressive tumor phenotype characterized by poorly differentiated tumor cells that infiltrated throughout the stroma. This high-grade carcinoma revealed elevated cell proliferation in a random pattern, loss of keratin 1 and diffuse deposition of laminin 5 gamma2 chain. When II-4 cell variants were seeded into type I collagen gels as an in vitro assay for cell migration, we found that only E-cadherin-deficient cells detached, migrated as single cells and expressed N-cadherin. Function-blocking studies demonstrated that this migration was matrix metalloproteinase-dependent, as GM-6001 and TIMP-2, but not TIMP-1, could block migration. Gene expression profiles revealed that E-cadherin-deficient II-4 cells demonstrated increased expression of proteases and cell-cell and cell-matrix proteins. These findings showed that loss of E-cadherin-mediated adhesion plays a causal role in the transition from low- to high-grade squamous cell carcinomas and that the absence of E-cadherin is an important prognostic marker in the progression of this disease.

Gene expression profiles reveal that DCN, DIO1, and DIO2 are underexpressed in benign and malignant thyroid tumors

To investigate the molecular events involved in the pathogenesis and/or progression of thyroid tumors, we compared the gene expression profiles of three thyroid carcinoma cell lines, which represent major tumor subtypes of thyroid cancer and normal thyroid tissue. Using cDNA array methodology, we investigated the expression of 1807 open reading frame expressed sequence tags (ORESTES), selected from head and neck tumor libraries generated through the Brazilian Human Cancer Project-LICR/FAPESP. We found that 505 transcripts were differentially expressed in the thyroid carcinoma cell lines. Using a more stringent criterion, transcripts underexpressed or overexpressed more than fivefold in 1 of 3 or 3 of 3 carcinoma cell lines, a list of 55 ESTs were detected. Five candidate genes were further validated by quantitative polymerase chain reaction (qPCR) in an independent set of 52 thyroid tumors and 22 matched normal thyroid tissues. DCN was found underexpressed in a high percentage of the follicular thyroid adenomas, follicular thyroid carcinomas, and follicular variant of papillary thyroid carcinomas. DIO1 and DIO2 were underexpressed in nearly all papillary thyroid carcinomas. These genes not only could help to better define a tumor signature for thyroid tumors, but may, in part, also become useful as potential targets for thyroid tumor treatment.

Vitronectin in human breast carcinomas

We have analysed the occurrence of the extracellular glycoprotein vitronectin in carcinomas and normal tissue of human breast. Immunohistochemical analysis of carcinomas revealed a strong vitronectin accumulation in extracellular matrix (ECM) around some cancer cell clusters and in the subendothelial area of some blood vessels. In normal tissue, vitronectin had a homogeneous periductal occurrence, with local accumulation much lower than that in the carcinomas. Using a new solid phase radioligand assay, the vitronectin concentrations of extracts of carcinomas and normal breast tissue were determined and found to be indistinguishable. Comparison of the vitronectin and the hemoglobin concentrations of the extracts showed that their vitronectin content was not derived from blood contamination. Vitronectin mRNA was undetectable in both carcinomas and normal tissue. We conclude that vitronectin is not synthesised locally in breast tissue but derived by leakage from vessels, followed by extracellular accumulation in patterns distinctly different in carcinomas and normal tissue. The observation of a high vitronectin content in the carcinomas and its localisation in the tissue contributes to the clarification of the role of vitronectin in tumour biology in interaction with the plasminogen activation system and integrins.

Expression of MMPS, MT-MMP, and TIMPs in squamous cell carcinoma of the oral cavity: correlations with tumor invasion and metastasis

BACKGROUND

Matrix metalloproteinases (MMPs) that degrade the extracellular matrices (ECMs) have been thought to play an important role in both the invasion and metastasis of tumors. However, the detailed role of MMPs and TIMPs (tissue inhibitors of MMP) on the biological behavior of tumor cells has yet to be elucidated in vivo. The aim of the present study was thus to determine whether expression of MMPs on tumor cells is associated with such clinicopathological features as the invasive and metastatic potential.

MATERIALS AND METHODS

This study included 96 cases of primary oral squamous cell carcinoma (OSCC), of which 38 cases showed lymph node metastases. The relationship between the expression of MMPs and the staining of ECMs, the mode of tumor invasion, nodal involvement, and expression of TIMPs was immunohistochemically examined.

RESULTS

First of all, a decrease in the staining of ECMs was observed in cases with an increased expression of MMP-1, -2, and -9. The association between the expression of MMPs and the loss of ECMs was thus found to be statistically significant. Secondly, in both invasive and metastatic cases, a marked expression of MMP-1, -2, -3, -9 and MT1-MMP was frequently observed. The association of the expression of MMPs both with the mode of tumor invasion and nodal involvement was thus found to be statistically significant. Thirdly, TIMP-2 was thus found not to significantly decrease in metastatic cases, while TIMP-1 expression significantly increased in metastatic cases.

CONCLUSION

These results suggest that tumor progression is dependent on the ability of tumor cells to degrade ECMs, while the metastasis of tumors is regulated by many types of MMPs, and the overproduction of MMPs therefore appears to be more important for metastasis than the production of TIMPs in vivo.

Improved survival for patients with clinically T1/T2, N0 tongue tumors undergoing a prophylactic neck dissection

BACKGROUND

Prophylactic surgical treatment of the neck in "early tongue tumors" is a controversial issue.

METHODS

From a database of 226 patients with squamous cell carcinoma of the tongue treated at Canniesburn Hospital, Glasgow, U.K., between 1980 and 1996, a total of 137 patients with a minimum follow up of 24 months or until death were clinically identified as being T1/T2, N0 (UICC) when first seen. These patients were divided into three groups according to the management of the neck; 53 patients did not have a neck dissection at any time (NKD0), 47 patients underwent a synchronous neck dissection at the time of treatment of the primary (NKDS), and 37 patients subsequently required a metachronous neck dissection when lymph node metastasis became clinically apparent (NKDM). These three groups were compared with respect to age, sex, site, duration of symptoms, previous treatment (if any), initial treatment protocol, resection margin, type of neck dissection (if any), loco-regional recurrence, systemic escape, number of positive lymph nodes, and presence of extracapsular spread. Disease-related survival was calculated using Kaplan-Meier survival curves with logrank test and chi-square statistical analysis.

RESULTS

The pT stage was upgraded to T3/4 in 3/53 patients (6%) of the NKD0 group, 11/47 patients (23%) of the NKDS group, and 2/37 patients (5%) of the NKDM group (p < 0.001). The 5-year determinate survival rates for the three groups were: NKD0 59.7%, NKDS 80.5%, NKDM 44.8%, and (NKD0 + NKDM) 53.6% with a statistically significant improvement in survival for NKDS vs NKDM (logrank 10.58, p = 0.001) and for NKDS vs (NKD0 + NKDM) (logrank 6.06, p = 0.014). The incidences of positive nodes in the NKDS and NKDM groups were 18/47 patients (38%) and 32/37 patients (86%) respectively. Neck positive patients in the NKDM group had a significantly greater number of positive nodes in comparison with N positive patients in the NKDS group (chi trend, p = 0.001), a higher incidence of extracapsular spread, 30/32 vs 9/18 (chi test, p < 0. 0001), and decreased survival. The incidence of occult cervical metastasis for the whole group was 41%.

CONCLUSION

Patients with clinical T1/2, N0 tongue tumors who underwent a synchronous neck dissection had an improved survival outcome even though as a group they had a higher incidence of occult metastasis, relatively more T2 lesions, a worse pT stage, and had more posterior third lesions requiring more difficult initial surgery. Tongue tumors have a high incidence of subclinical nodal disease, which is less curable when it presents clinically. The information gleaned from the nodal status allows a more informed plan of adjuvant therapy.