Expression of matrix metalloproteinases (MMP-1 and -2) and their inhibitors (TIMP-1, -2 and -3) in oral lichen planus, dysplasia, squamous cell carcinoma and lymph node metastasis

Analysis of transcriptome expression profiling data in oral leukoplakia and early and late‑stage oral squamous cell carcinoma

The present study screened, potential prognostic biomarkers for oral carcinogenesis. The GSE85195 dataset, which consisted of oral leukoplakia (OL) and early and late-stage oral squamous cell carcinoma (OSCC) samples, was used. The differentially expressed genes (DEGs) in early OSCC vs. OL, late OSCC vs. OL and late OSCC vs. early OSCC groups were screened using the limma package in R. The Short Time-series Expression Miner software package was used to cluster DEGs with similar expression patterns in the course of disease progression (from OL to early and then late-stage OSCC). Moreover, the Database for Annotation, Visualization and Integrated Discovery online analysis tool was used to perform Gene Ontology functional annotation and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis. A protein-protein interaction (PPI) network was also constructed using the Search Tool for the Retrieval of Interacting Genes/Proteins database. Reverse transcription-quantitative PCR was performed to assess the mRNA expression levels of hub node genes in clinical samples, and receiver operating characteristic curve analysis was performed to assess the prognostic value of the hub genes. A total of 4,595, 6,042 and 2,738 DEGs were screened in the early OSCC vs. OL, late OSCC vs. OL and late OSCC vs. early OSCC groups, respectively. A total of 665 overlapping genes were identified when the screened DEGs were compared. Cluster 1 and cluster 7 were identified as the significant clusters, which contained 496 and 341 DEGs, respectively. A PPI network was constructed with 440 interaction pairs. There were five differentially expressed hub nodes identified in different stages from OL to OSCC. The results of the present study indicated that fibronectin 1, signal transducer and activator of transcription 1, collagen type II α1 chain, collagen type X α1 chain and collagen type IV α6 chain might serve as independent diagnostic factors for OL and OSCC, and as prognostic biomarkers for OL carcinogenesis.

Role of MMP1 and MMP10 in local invasion and distant metastasis in different levels of oral squamous cell carcinoma - A immunohistochemical comparative study

Background

Matrix metalloproteinases (MMPs) are basically a part of a large family of proteolytic enzymes. They play an important role in degrading extracellular matrix and basement membrane, which is a basic mechanism in local invasion and tumour metastasis. The aim of this study was to evaluate immunohistochemically the expression of MMP1 and MMP10 in tumour invasion locally and at distant levels, including lymph nodes at different levels in oral squamous cell carcinoma (OSCC).

Materials and Methods

A total of 50 tissue samples with clinically confirmed OSCC and 15 normal oral mucosal tissues will be included in the study. Immunohistochemical staining will be performed for the demonstration of MMP1 and MMP10 in lesional tissue, perilesional tissue, and lymph nodes of different levels that were evaluated with respect to microscopic features.

Results

All OSCC cases had MMP1 and MMP10 expression levels. The expression increased as the nodal level increased from level I to level V. This difference was statistically significant at P < 0.001 Both MMPs were not expressed in normal epithelial cells. There was no significant correlation between MMP1 and MMP10 expression.

Conclusion

This study showed that MMP1 and MMP10 are expressed in the tissues of OSCC and may serve as prognostic indicators for the disease.

Comparative study of laminin332-γ2 chain expression in oral lichen planus and squamous cell carcinoma by immunohistochemistry

BACKGROUND

Classification of oral lichen planus (OLP) as a condition with malignant potential is still controversial. One of the major properties of malignancy is invasion. Ln332-γ2 chain plays a critical role in invasive activity of cancer cells. This study aims to compare Ln332-γ2 chain expression in OLP, oral epithelial dysplasia (OED) and oral squamous cell carcinoma (OSCC).

METHODS

Ln332-γ2 expression was evaluated in 16 epithelial hyperplasia with no dysplasia (group A), 16 OLP (group B), 18 OED (group C) and 18 OSCC (group D) by immunohistochemistry.

RESULTS

Except in A group, Ln332-γ2 expression was detected in other groups. There was a significant difference in Ln332-γ2 expression among B, C and D groups as well as between B and D, C and D groups (P< 0.001). However, there was no significant difference between B and C groups (P= 0.999).

CONCLUSIONS

According to the findings of this study, the likelihood of similarity of OLP with premalignant dysplastic lesion can be suggested. This is not corroborating OLP definitive transformation to an OSCC. But it might be advisable that OLPs with >10% Ln332- γ2 expression may have a higher risk of cellular invasion occurrence and malignant transformation.

Modulating the ERK1/2-MMP1 Axis through Corosolic Acid Inhibits Metastasis of Human Oral Squamous Cell Carcinoma Cells

Corosolic acid (CA; 2α-hydroxyursolic acid) is a natural pentacyclic triterpenoid with antioxidant, antitumour and antimetastatic activities against various tumour cells during tumourigenesis. However, CA’s antitumour effect and functional roles on human oral squamous cell carcinoma (OSCC) cells are utterly unknown. In this study, our results demonstrated that CA significantly exerted an inhibitory effect on matrix metalloproteinase (MMP)1 expression, cell migration and invasion without influencing cell growth or the cell cycle of human OSCC cells. The critical role of MMP1 was confirmed using the GEPIA database and showed that patients have a high expression of MMP1 and have a shorter overall survival rate, confirmed on the Kaplan–Meier curve assay. In the synergistic inhibitory analysis, CA and siMMP1 co-treatment showed a synergically inhibitory influence on MMP1 expression and invasion of human OSCC cells. The ERK1/2 pathway plays an essential role in mediating tumour progression. We found that CA significantly inhibits the phosphorylation of ERK1/2 dose-dependently. The ERK1/2 pathway played an essential role in the CA-mediated downregulation of MMP1 expression and in invasive motility in human OSCC cells. These findings first demonstrated the inhibitory effects of CA on OSCC cells’ progression through inhibition of the ERK1/2–MMP1 axis. Therefore, CA might represent a novel strategy for treating OSCC.

Melanoma-Derived Exosomes Endow Fibroblasts with an Invasive Potential via miR-21 Target Signaling Pathway

Background

Tumor-derived exosomes are messengers that participate in tumor progression. Fibroblasts are associated with the metastasis of cancer depending on their cellular plasticity. We hypothesize that tumor-derived exosomes endow the fibroblasts in tumor microenvironment with invasive phenotype to the benefit of tumor metastasis.

Materials and Methods

Exosomes derived from B16-F10 cells were identified by nanoparticle tracking analyzer (NTA), dynamic light scattering (DLS), Western blot (WB), and transmission electron microscopy (TEM). Cell invasion and migration assays were performed using the xCELLigence real-time cell analyzer (RTCA). Role of tumor-derived exosomal miR-21 in cell invasion was determined by qPCR.

Results

The invasion analysis showed that exosome-treated fibroblast cells had greater invasive capability as compared to untreated fibroblast cells, with the higher expressions of MMP2 and MMP9. miR-21 is at least partially responsible for this effect. After ingestion of melanoma-derived exosomes during incubation, mouse embryonic fibroblasts cells emerged cellular invasiveness with the presentation of a marked increase in miR-21 expression. MiR-21 promoted invasion of fibroblasts by down-regulation of tissue inhibitor of metalloproteinase 3 (TIMP3) expression and increasing of matrix metalloprotein (MMP) expression in fibroblast cells via melanoma-derived exosomes in a time-dependent manner.

Conclusion

Our results suggest that tumor-derived exosomes may facilitate stromal fibroblasts an aggressive phenotype to equip the tumor progression.

Interaction of human oral cancer and the expression of virulence genes of dental pathogenic bacteria

Oral squamous cell carcinoma (OSCC) are one of the major causes of cancer morbidity and mortality worldwide. Dental microbiome has been considered as inducing agents in oral carcinogenesis. Therefore, the objective of this study was to investigate the interaction of the gene expression of the dental microbiome and OSCC patients. A cross-sectional study was designed by recruiting confirmed OSCC patients attending the University hospital during October 2018 and July 2019. The dental bacteria were isolated and confirmed by PCR technique. The expression of host and bacterial virulence genes was determined using qPCR. This study shows that 54% of T. forsythia found to be the most predominant organisms in 30 positive cases, followed by 34% of Campylobacter rectus and 29% of Prevotella intermedia. The expression of mRNA levels of bspA, csxA, fadA and interpain A in the OSCC- bacteria positive cases was significantly higher than the control group (P < 0.001). It was further found that interpainA, csxA, fadA, and bspA genes have the potential effects on the cellular gene expression in OSCC patients. A significant correlation was seen between expression patterns of CXCL10, DIAPH1, NCLN and MMP9 genes with interpain A, fadA, and bspA involved in OSCC cases The results indicate that the species specific bacteria may play a role in triggering chronic inflammation in OSCC patients. Therefore, alteration in the gene expression through the dental microbiome could be used as an alternative target in the clinical practice to detect OSCC.

Telomerase Reverse Transcriptase (TERT) Expression, Telomerase Activity, and Expression of Matrix Metalloproteinases (MMP)-1/-2/-9 in Feline Oral Squamous Cell Carcinoma Cell Lines Associated With Felis catus Papillomavirus Type-2 Infection

Telomerase activity contributes to cell immortalization by avoiding telomere shortening at each cell division; indeed, its catalytic subunit telomerase reverse transcriptase (TERT) is overexpressed in many tumors, including human oral squamous cell carcinoma (hOSCC). In these tumors, matrix metalloproteinases (MMPs), a group of zinc-dependent endopeptidases involved in cell migration, contribute to invasive potential of cancer cells. A proportion of hOSCC is associated with infection by high-risk human papillomavirus (HR-HPVs), whose E6 oncogene enhances TERT and MMPs expression, thus promoting cancer progression. Feline oral squamous cell carcinoma (FOSCC) is a malignant tumor with highly invasive phenotype; however, studies on telomerase activity, TERT, and MMPs expression are scarce. In this study, we demonstrate telomerase activity, expression of TERT, and its transcriptional activator cMyc along with expression of MMP-1, -2, and -9 in FOSCC-derived cell lines SCCF2 and SCCF3, suggesting a contribution by these pathways in cell immortalization and invasion in these tumors. Recent studies suggest that a sub-group of FOSCC as well as SCCF2 and SCCF3 are associated with Felis catus PV type-2 (FcaPV-2) infection. However, in this work, FcaPV-2 E6 gene knock-down caused no shift in either TERT, cMyc, or MMPs levels, suggesting that, unlike its human counterpart, the viral oncogene plays no role in their regulation.

Effect of a structured plaque control on MMP-1 and MMP-9 crevicular levels in patients with desquamative gingivitis associated with oral lichen planus

OBJECTIVES

No data are available in the literature on the extent to which the immune host-response and bacterial-elicited inflammation separately contributes to the increase in gingival crevicular fluid (GCF) levels of inflammatory biomarkers in patients affected by desquamative gingivitis (DG) secondary to oral lichen planus (OLP). The aim of this study was to investigate the effect of a structured plaque control intervention on GCF levels of MMP-1 and MMP-9 in OLP patients with DG and to compare them with those of non-OLP patients.

MATERIALS AND METHODS

The study population consisted of 18 unrelated Caucasian patients with DG, while 18 periodontally healthy subjects were recruited for the control group. Periodontal parameters and GCF biomarker amounts were evaluated at baseline and 2 months after a structured plaque control intervention, comprising professional oral hygiene sessions, manual toothbrushing, and interdental cleaning advice, only for DG patients. Determination of MMP-1 and MMP-9 levels was carried out by means of an enzyme-linked immunosorbent assay.

RESULTS

Plaque control program led to improvement in all examined clinical parameters and resulted in significant decrease in GCF total amount and concentration of MMP-1 and MMP-9 in comparison to baseline (p < 0.001). However, MMP-1 and MMP-9 levels in DG patients were still significantly higher than those in the healthy control group (p < 0.01).

CONCLUSIONS

These findings would seem to support an intrinsic upregulated expression of MMPs in DG patients that is exacerbated by bacterial plaque.

CLINICAL RELEVANCE

The present outcomes provide further scientific grounds for the importance of strict professional oral hygiene sessions in DG patients.

Matrix metalloproteinase (MMP) and immunosuppressive biomarker profiles of seven head and neck squamous cell carcinoma (HNSCC) cell lines

BACKGROUND

Biomarkers like programmed death ligand-1 (PDL1) have become a focal point for immunotherapeutic checkpoint inhibition in head and neck squamous cell carcinoma (HNSCC). However, it's only part of the total immunosuppressive biomarker profile of HNSCC cells. Matrix metalloproteinases (MMPs) are enzymes that break down the basement membrane allowing cancer cells to metastasize and play an important role in the tumor microenvironment. MMPs can also activate certain cytokines, growth factors, and chemokines post-translationally. The objective of this study was to determine MMP and biomarker profiles of seven different HNSCC cell lines.

METHODS

Authenticated cell lines were grown in minimal media at 1×106 viable cells/mL and incubated at 37 °C. After 24 hrs supernatants were collected, and adhering cells were lysed. Multiplex immunoassays were used to determine MMP1, MMP7, MMP9, IL-6, VEGFA, IL-1α, TNF-α, GM-CSF, IL-1RA, and IL-8 concentrations in supernatants. ELISAs were used to determine PDL1, CD47, FASL, and IDO concentrations in cell lysates. A one-way ANOVA was fit to examine log-transformed concentrations of biomarkers between seven HNSCC cell lines, and pairwise group comparisons were conducted using post- hoc Tukey's honest significance test (α=0.05).

RESULTS

Significant differences (P<0.05) in MMP and biomarker concentrations were found between the seven HNSCC cell lines. For example, MMP9 was highest in SCC25 and UM-SCC99, MMP7 was highest in SCC25 and UM-SCC19, and MMP1 was highest in SCC25.

CONCLUSIONS

These results suggest different patients' HNSCC cells can express distinct profiles of select biomarkers and MMPs, which could be due to metastatic stage of the cancer, primary tumor site, type of tissue the tumor originated from, or genomic differences between patients. MMP and biomarker expression profiles should be considered when choosing cell lines for future studies. The results support the reason for personalized medicine and the need to further investigate how it can be used to treat HNSCC.

The interplay of matrix metalloproteinase-8, transforming growth factor-β1 and vascular endothelial growth factor-C cooperatively contributes to the aggressiveness of oral tongue squamous cell carcinoma

Background:

Matrix metalloproteinase-8 (MMP-8) has oncosuppressive properties in various cancers. We attempted to assess MMP-8 function in oral tongue squamous cell carcinoma (OTSCC).

Methods:

MMP-8 overexpressing OTSCC cells were used to study the effect of MMP-8 on proliferation, apoptosis, migration, invasion and gene and protein expression. Moreover, MMP-8 functions were assessed in the orthotopic mouse tongue cancer model and by immunohistochemistry in patient samples.

Results:

MMP-8 reduced the invasion and migration of OTSCC cells and decreased the expression of MMP-1, cathepsin-K and vascular endothelial growth factor-C (VEGF-C). VEGF-C was induced by transforming growth factor-β1 (TGF-β1) in control cells, but not in MMP-8 overexpressing cells. In human OTSCC samples, low MMP-8 in combination with high VEGF-C was an independent predictor of poor cancer-specific survival. TGF-β1 treatment also restored the migration of MMP-8 overexpressing cells to the level of control cells. In mouse tongue cancer, MMP-8 did not inhibit metastasis, possibly because it was eliminated in the peripheral carcinoma cells.

Conclusions:

The suppressive effects of MMP-8 in OTSCC may be mediated through interference of TGF-β1 and VEGF-C function and altered proteinase expression. Together, low MMP-8 and high VEGF-C expression have strong independent prognostic value in OTSCC.

Salivary MMP-1, MMP-2, MMP-3 and MMP-13 Levels in Patients with Oral Lichen Planus and Squamous Cell Carcinoma

The aim of present study was to evaluate salivary matrix metalloproteinase-1 (MMP-1), MMP-2, MMP-3 and MMP-13 levels in patients with oral lichen planus (OLP) and squamous cell carcinomas (SCC) as well as in healthy controls. Thirty cases of OLP (bilateral lesions, papular and reticular lesions, and Wickham lines) clinically and histopathologically (group A), 30 with oral SCCs (group B), and 30 with no history of oral cancer, other lesions or lichen planus (group C) were enrolled at the Department of Oral Medicine School of Dentistry, Zahedan, Iran. Unstimulated whole saliva was collected and laboratory measurement of salivary concentration of MMP-1, MMP-2, MMP-3 and MMP-13 was conducted by immuno-sorbent enzyme-linked methods. Data analysis was performed with Kruskal-Wallis and Mann-Whitney tests and Pearson’s correlation coefficients. In the present study, MMP-2 and MMP-13 levels were higher in oral SCC patients than in OLP and healthy individuals. More research is required to assess MMP links with tumor invasion.

Osteoactivin regulates head and neck squamous cell carcinoma invasion by modulating matrix metalloproteases

Nearly 60% of patients with head and neck squamous cell carcinoma (HNSCC) die of metastases or locoregional recurrence. Metastasis is mediated by cancer cell migration and invasion, which are in part dependent on extracellular matrix degradation by matrix metalloproteinases. Osteoactivin (OA) overexpression plays a role in metastases in several malignancies, and has been shown to upregulate matrix metalloproteinase (MMP) expression and activity. To determine how OA modulates MMP expression and activity in HNSCC, and to investigate OA effects on cell invasion, we assessed effects of OA treatment on MMP mRNA and protein expression, as well as gelatinase and caseinolytic activity in HNSCC cell lines. We assessed the effects of OA gene silencing on MMP expression, gelatinase and caseinolytic activity, and cell invasion. OA treatment had differential effects on MMP mRNA expression. OA treatment upregulated MMP-10 expression in UMSCC14a (p = 0.0431) and SCC15 (p < 0.0001) cells, but decreased MMP-9 expression in UMSCC14a cells (p = 0.0002). OA gene silencing decreased MMP-10 expression in UMSCC12 cells (p = 0.0001), and MMP-3 (p = 0.0005) and -9 (p = 0.0036) expression in SCC25 cells. In SCC15 and SCC25 cells, OA treatment increased MMP-2 (p = 0.0408) and MMP-9 gelatinase activity (p < 0.0001), respectively. OA depletion decreased MMP-2 (p = 0.0023) and -9 (p < 0.0001) activity in SCC25 cells. OA treatment increased 70 kDa caseinolytic activity in UMSCC12 cells consistent with tissue type plasminogen activator (p = 0.0078). OA depletion decreased invasive capacity of UMSCC12 cells (p < 0.0001). OA's effects on MMP expression in HNSCC are variable, and may promote cancer cell invasion.

Evaluation of Potential Risk Factors that contribute to Malignant Transformation of Oral Lichen Planus: A Literature Review

AIM

Many studies have suggested that a lesion originally diagnosed as oral lichen planus (OLP) has different possibilities of undergoing malignant transformation in time, although these findings remain a controversial issue; for example, some studies reported different values of potential malignancy of OLP.

INTRODUCTION

World Health Organization (WHO) classifies OLP as a "potentially malignant disorder" with unspecified malignant transformation risk, and suggests that OLP patients should be closely monitored. Numerous studies have attempted to confirm the malignant transformation potential of OLP.

REVIEW RESULTS

The Cochrane Controlled Trials Register, Medline and EMBASE databases, PubMed, Google Scholar, Ovid, Up To Date, BMJ Clinical Evidence, MD Consult, and Science Direct were searched for papers published between 1997 and 2015. The medical subject heading search terms were "lichen planus," "oral lichen planus," "erosive oral lichen planus," "dysplasia," "oral precancerous condition," "oral premalignant condition," oral cancer, oral squamous cell carcinoma (OSCC), and atrophic lichen planus. A total of 120 English language abstracts were reviewed, and 50 relevant articles identified. Because of the extensive literature on the association between OLP and SCC, we have divided the data into genetic and non-genetic factors for more accurate assessment.

CONCLUSION

In this evidence base, malignant transformation ranges from 0 to 37% with a mean of 4.59%. The highest rate of malignancy was noted in erythematosus and erosive lesions. In this way, follow-up of OLP patients could be carried out more efficiently and appropriately.

CLINICAL SIGNIFICANCE

Oral lichen planus is a premalignant lesion. All types of OLP in any site of oral mucosa must be monitored regularly.

Largescale Transcriptomics Analysis Suggests Over-Expression of BGH3, MMP9 and PDIA3 in Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (OSCC) has been reported as the most prevalent cancer of the head and neck region, while early diagnosis remains challenging. Here we took a comprehensive bioinformatics study on microarray data of 326 OSCC clinical samples with control of 165 normal tissues. The cell interaction pathways of ECM-receptor interaction and focal adhesion were found to be significantly regulated in OSCC samples. Further analysis of the topological properties and expression consistency identified that three hub genes in the gene interaction network, MMP9, PDIA3 and BGH3, were consistently up-expressed in OSCC samples. When being validated on additional microarray datasets of 41 OSCC samples, the validation rate of over-expressed BGH3, MMP9, and PDIA3 reached 90%, 90% and 84% respectively. At last, immuno-histochemical assays were done to test the protein expression of the three genes on newly collected clinical samples of 35 OSCC, 20 samples of pre-OSCC stage, and 12 normal oral mucosa specimens. Their protein expression levels were also found to progressively increase from normal mucosa to pre-OSCC stage and further to OSCC (ANOVA p = 0.000), suggesting their key roles in OSCC pathogenesis. Based on above solid validation, we propose BGH3, MMP9 and PDIA3 might be further explored as potential biomarkers to aid OSCC diagnosis.

Possible salivary and serum biomarkers for oral lichen planus

There are few reports concerning the potential for clinical application of oxidative stress (OS) and collagen degradation markers in oral lichen planus (OLP) patients. We investigated the possibility of using some disease-related biomarkers in saliva and serum of OLP patients. Our study included 30 patients with OLP and 30 controls. We evaluated serum and salivary OS biomarkers including 8-OHdG, MDA, uric acid, TAC and GPx. We also investigated collagen degradation markers such as CTX I and MMP-8. We found significantly increased salivary levels of MMP-8 and CTX I in the OLP group compared to controls and significant differences between the OLP and control groups in serum and saliva for 8-OHdG, MDA (significantly increased), uric acid, TAC and GPx (significantly reduced). Currently there are no criteria for evaluating which OLP patients have a greater risk of malignant transformation. In addition to clinical surveillance, the serum and salivary biomarkers that we evaluated may be useful biomarkers for monitoring OLP patients in the future.

In-vivo nonlinear optical microscopy (NLOM) of epithelial-connective tissue interface (ECTI) reveals quantitative measures of neoplasia in hamster oral mucosa

The epithelial-connective tissue interface (ECTI) plays an integral role in epithelial neoplasia, including oral squamous cell carcinoma (OSCC). This interface undergoes significant alterations due to hyperproliferating epithelium that supports the transformation of normal epithelium to precancers and cancer. We present a method based on nonlinear optical microscopy to directly assess the ECTI and quantify dysplastic alterations using a hamster model for oral carcinogenesis. Neoplastic and non-neoplastic normal mucosa were imaged in-vivo by both multiphoton autofluorescence microscopy (MPAM) and second harmonic generation microscopy (SHGM) to obtain cross-sectional reconstructions of the oral epithelium and lamina propria. Imaged sites were biopsied and processed for histopathological grading and measurement of ECTI parameters. An ECTI shape parameter was calculated based on deviation from the linear geometry (ΔLinearity) seen in normal mucosa was measured using MPAM-SHGM and histology. The ECTI was readily visible in MPAM-SHGM and quantitative shape analysis showed ECTI deformation in dysplasia but not in normal mucosa. ΔLinearity was significantly (p < 0.01) higher in dysplasia (0.41±0.24) than normal (0.11±0.04) as measured in MPAM-SHGM and results were confirmed in histology which showed similar trends in ΔLinearity. Increase in ΔLinearity was also statistically significant for different grades of dysplasia. In-vivo ΔLinearity measurement alone from microscopy discriminated dysplasia from normal tissue with 87.9% sensitivity and 97.6% specificity, while calculations from histology provided 96.4% sensitivity and 85.7% specificity. Among other quantifiable architectural changes, a progressive statistically significant increase in epithelial thickness was seen with increasing grade of dysplasia. MPAM-SHGM provides new noninvasive ways for direct characterization of ECTI which may be used in preclinical studies to investigate the role of this interface in early transformation. Further development of the method may also lead to new diagnostic approaches to differentiate non-neoplastic tissue from precancers and neoplasia, possibly with other cellular and layer based indicators of abnormality.

Tumor progression driven by pathways activating matrix metalloproteinases and their inhibitors

BACKGROUND

Laryngeal squamous cell carcinoma (LSCC) is still a problem worldwide. In some publications interactions between the expression of matrix metalloproteinases (MMPs), particularly MMP-2 and MMP-9, and their tissue inhibitors (TIMPs) implicated during cancer progression were suggested.

METHODS

The immunohistochemical staining using primary antibody against MMP-2, MMP-9, TIMP-1, TIMP-2, and TIMP-3 were performed. The research group consists of primary N(0) LSCC (20 cases), primary N(+) LSCC (17 cases), and 18 cases of normal mucosa.

RESULTS

Studied MMPs and TIMPs were localized in tumor cells and tumor stroma compartment. MMP-2 expression was higher in stroma compared to tumor cells. MMP-9, TIMP-1, TIMP-2, and TIMP-3 expression was higher in tumor cells than in tumor stroma (P < 0.05). In tumor stroma MMP-2, MMP-9, TIMP-1, and TIMP-3 expression, in LSCC N(0) vs. LSCC N(+) was significantly higher (P < 0.05). The ratios between MMP-2 and TIMP-3 expression were statistically significant (N(0) vs. N(+); P = 0.012). The analyses using classification trees predicted the probability of metastases according to TIMP-3/MMP-14/MMP-2 and MMP-9/TIMP-1 expression levels.

CONCLUSIONS

The presence of MMP-2, MMP-9, TIMP-1, TIMP-2, TIMP-3 expression in tumor cells and in tumor stroma, and additionally different expression according to lymph node involvement suggested of their impact during cancer progression. The significant correlation between TIMP-3 expression and the presence of lymph node metastases and MMP-2 expression might suggest the importance of TIMP-3 as a prognostic factor during tumor progression. The evaluation of molecular markers which participate in MMP-2 activation pathway have a major impact during metastasis.

The EGF signaling pathway influences cell migration and the secretion of metalloproteinases by myoepithelial cells in pleomorphic adenoma

During tumor development, benign neoplastic cells are influenced by the expression of cytokines, growth factors, and proteases present in the tumor microenvironment. Epidermal growth factor (EGF) is the most studied growth factor and is considered important for cell proliferation and migration. Metalloproteinases (MMPs) are also involved in tumor progression. The present study aimed to analyze the proliferation, viability and migration index of pleomorphic adenoma myoepithelial cells, in addition to the secretion of MMPs with EGF supplementation. Benign myoepithelial cells were cultured with two different EGF doses (5 and 10 ng/ml), and the influence of EGF on cell proliferation and viability, using trypan blue and MTT assays, respectively, after 24, 48, and 72 h, was evaluated. To analyze cellular morphology, hematoxylin-eosin staining and indirect immunofluorescence using the anti-vimentin antibody, was performed. In vitro migration assays were performed in Transwell chambers with an 8-μm pore covered with Matrigel and supplemented with 5 or 10 ng/ml of EGF, after 96 h. After 4 days of cell culture, ELISA was performed to determine the MMP-2 and MMP-13 levels. One-way analysis of variance (ANOVA) with post hoc Tukey test was applied, with a significance level of 0.05. The results revealed that EGF influences myoepithelial cell morphology, without alteration of proliferation and viability. The migration assay showed that EGF increased the mean index from 16 % in the control group to 40 and 76 % for 5 and 10 ng/ml of EGF, respectively. ELISA revealed that when the cells were supplemented with either of the EGF doses, an increase in MMP-2 levels was observed when compared with the control group (C). This study concludes that EGF aids in the production of MMP-2, which favors the dissolution of the basement membrane, contributing to cell migration and tumor progression, hence permitting contact between the myoepithelial cells and stroma.

The role of MMP-2 and MMP-9 as prognostic markers in the early stages of tongue squamous cell carcinoma

BACKGROUND

Tongue cancer is the most common intra-oral malignancy with a high rate of morbidity and mortality owing to its increased propensity for tumor invasion and metastasis. These processes require a controlled degradation of the extracellular matrix. Matrix Metalloproteinase-2 (MMP-2) and Matrix Metalloproteinase-9 (MMP-9) are known to be important regulators of matrix lysis and play a significant role in the metastasis of malignancies.

AIM AND OBJECTIVES

To study the expression of MMP-2 and MMP-9 in the early stages of tongue squamous cell carcinoma and find the association between their expression and local recurrence, metastasis, and survival rates of the subjects.

MATERIALS AND METHODS

Fifty-nine tumor biopsy samples of tongue squamous cell carcinoma in T1 N0 M0 and T2 N0 M0 stages were immunostained with MMP-2 and MMP-9 antibodies. The immunohistochemical expression was compared with the patient characteristics and outcome.

RESULTS

Cytoplasmic expression of MMP-2 correlated with that of MMP-9 (r = 0.716, P < 0.001). Greater expression of MMP-2 and MMP-9 was observed in patients who subsequently developed local recurrence (P = 0.044 and P < 0.001, respectively), regional and/or distant metastasis (P < 0.001 and P = 0.001, respectively) of the tumor. Further, a higher expression of these biomarkers was associated with shorter survival. MMP-9 was found to have better specificity for local recurrence, metastasis and survival.

CONCLUSION

Our results showed that these biomarkers may serve as indicators of a patient's risk potential for poor prognosis and presage the need for more aggressive treatment measures.

Molecular changes in invasive front of oral cancer

Treatment planning for oral squamous cell carcinoma (OSCC) is based on the clinical TNM (Tumor, Node and Metastasis) classification. This system operates on the assumption that small tumours without clinical spread have a better prognosis than larger tumours with metastases. However, it is a well-known fact that some tumours with the same clinical staging show different growth patterns and clinical behaviour. This makes the prognosis for patients with OSCC difficult to predict on the basis of clinical staging alone. Although many histopathological characteristics of OSCC have been identified as prognostic factors, none is believed to be completely infallible. Therefore, a great need exists for more reliable prognostic markers, which will assist in treatment decisions. It is now well documented that several molecular events of significance for tumour spread, such as gain and loss of adhesion molecules, secretion of proteolytic enzymes, increased cell proliferation and initiation of angiogenesis occur at the tumour–host interface or invasive front, where the deepest and presumably most aggressive cells reside. This review describes the various molecular events and interactions, which take place in the invasive front of the OSCC, and elucidates their role as prognostic markers.

Collagen remodeling and peripheral immune cell recruitment characterizes the cutaneous Langerhans cell histiocytosis microenvironment

BACKGROUND

Langerhans cell histiocytosis (LCH) is a rare and potentially fatal disorder of unknown etiology arising from the accumulation of epidermal Langerhans-like cells in bone, skin, or other tissues. Tissue damage and morbidity results from lesional cytokine release, and we sought to investigate the LCH microenvironment using a combination of histological stains and immunohistochemistry.

METHODS

CD1a immunoreactivity was used to identify lesional cells in archival paraffin-embedded samples of cutaneous LCH. A combined Orcein and Giemsa stain identified immune cells in general (particularly granulocytes and mast cells) and extracellular matrix (particularly elastic fibers), while CD3 and CD68 staining identified T cells and macrophages, respectively. Collagen synthesis was investigated with Herovici staining, which discriminates newly synthesized from mature collagen, while cross-polar microscopy of picrosirius-stained sections identified changes in matrix organization.

RESULTS

Immune cells were consistently identified at the periphery of cutaneous LCH lesions. We quantified an increased number of thickened and disorganized elastic fibers surrounding lesions and an absence of elastic fibers within lesions. Furthermore, lesions exhibited a decrease in mature collagen fibers and a loss of supporting collagen matrix within lesions and compromised collagen integrity in adjacent tissue.

CONCLUSIONS

Cutaneous LCH lesions are associated with the peripheral recruitment of a variety of immune cells and are consistently characterized by localized elastosis, collagen damage, and remodeling.

Immunohistochemical correlation of matrix metalloproteinase-2 and tissue inhibitors of metalloproteinase-2 in tobacco associated epithelial dysplasia

Aim. To study the immunohistochemical expression of matrix metalloproteinase and tissue inhibitors of matrix metalloproteinase-2 in different histological grades of tobacco associated epithelial dysplasia and correlate the association between these proteases. Potentially malignant oral disorders (PMODs) progressing to oral cancer are related to the severity of epithelial dysplasia. Methods. A retrospective immunohistochemical study was carried out on 30 clinically and histologically proven cases of leukoplakia with dysplasia and 10 cases of normal buccal mucosa using anti-MMP-2 and anti-TIMP-2 monoclonal antibodies. Results. Mann Whitney U test, for comparing the expression of both MMP-2 and TIMP-2 in normal mucosa with dysplasia, was highly significant (P < 0.001). Kruskal-Wallis test to compare the median score of MMP-2 and TIMP-2 in different grades of dysplasia showed statistical significance (P < 0.001), and a Spearman's correlation between MMP-2 and TIMP-2 through different grades of dysplasia and cells observed showed positive correlation. Conclusion. Concomitant increase in the expression of both MMP-2 and TIMP-2 suggested that the activation of MMP-2 is dependent on TIMP-2 acting as a cofactor. Changes in TIMP-2 levels are considered important because they directly affect the level of MMP-2 activity.

Oral lichen planus: focus on etiopathogenesis

Lichen planus is a chronic mucocutaneous inflammatory disease, which frequently affects the oral mucosa of white females over 40 years old. Its aetiology remains uncertain and the pathogenesis is still the object of much speculation. The present paper presents the most well known antigens, and describes the action of different cells and proteins associated with the development of that disease, as well as the possible agents involved with its malignant transformation. Different external agents, especially virus, and internal agents, like stress, and the heat shock protein antigen expression, associated or not, can alter the basal keratinocytes of the oral mucosa making them susceptible to apoptosis by CD8(+) cytotoxic T cell as well as activate matrix metalloproteinase and mast cell degranulation, which produce a great range of inflammatory mediators and cytokines determining the clinical onset of the disease. Regarding carcinogenesis, since it is a complex process and presents multifactorial origin, it is believed that there may be a synergism between intrinsic, such as inflammation mediators, and extrinsic agents (tobacco, alcohol, viral infections) for the OLP malignant transformation to occur. However, further studies are needed to better understand the origin, pathogenesis and process of malignant transformation of OLP.

The immunohistochemical characterization of MMP-2, MMP-10, TIMP-1, TIMP-2, and podoplanin in oral squamous cell carcinoma

OBJECTIVES

The aim of this study was to immunohistochemically evaluate the expression of matrix metalloproteinase (MMP)-1, MMP- 2, tissue inhibitor of metalloproteinase (TIMP)-1, TIMP-2, and podoplanin in oral squamous cell carcinoma (OSCC). Immunohistochemical staining of podoplanin-positive lymphatic vessel density (LVD) was also assessed.

STUDY DESIGN

Forty cases of OSCC were analyzed by immunohistochemistry.

RESULTS

MMP-2, MMP-10, TIMP-1, TIMP-2, and podoplanin were detected in each of the 40 OSCC cases. The expression of MMP-2 was significantly correlated with histologic grade. The expression of podoplanin was positively correlated with gender and negatively correlated with tumor size. A significant positive correlation was also detected between LVD and the presence of lymph node metastases, gender, age, and diameter of the lymph node (if involved), as well as histologic grade.

CONCLUSIONS

The results are suggestive of important roles that MMP-2, MMP-10, TIMP-2, and podoplanin play in pathologic processes of OSCC, including invasion. Our findings also suggest that LVD may play a role in lymphatic metastasis and tumor progression.

Comparative analysis of basal lamina type IV collagen α chains, matrix metalloproteinases-2 and -9 expressions in oral dysplasia and invasive carcinoma

The aim of this study was to compare the expressions of basal lamina (BL) collagen IV α chains and matrix metalloproteinases (MMP)-2 and MMP-9 in oral dysplasia (OED) and invasive carcinoma. Ten cases each of OEDs, carcinomas-in situ and oral squamous cell carcinomas (OSCCs) were examined by immunohistochemistry. Another 5 cases, each of normal and hyperplastic oral mucosa, served as controls. Results showed that α1(IV)/α2(IV) and α5(IV)/α6(IV) chains were intact in BLs of control and OEDs. In BLs of carcinoma-in situ, α1(IV)/α2(IV) chains preceded α5(IV)/α6(IV) chains in showing incipient signs of disruption. OSCCs exhibited varying degrees of collagen α(IV) chain degradation. MMP-2 and MMP-9 were absent in controls and OED, but weakly detectable in carcinoma-in situ. In OSCC, these proteolytic enzymes were expressed in areas corresponding to collagen α(IV) chain loss. Enzymatic activity was enhanced in higher grade OSCC, and along the tumor advancing front. Overall the present findings suggest that loss of BL collagen α(IV) chains coincided with gain of expression for MMP-2 and MMP-9, and that these protein alterations are crucial events during progression from OED to OSCC.

Molecular communication between tumor-associated fibroblasts and head and neck squamous cell carcinoma

Over the past few decades, it has become increasingly clear that the lethality of cancers depends on more than the malignant cells themselves. The environment those malignant cells are exposed to is just as important a determinant of their behavior. Head and neck squamous cell carcinoma (HNSCC) is both common and deadly. It is the 6th most frequently occurring cancers, and prognosis is still generally poor. Recent evidence indicates that activated fibroblasts residing within the tumor stroma play a significant role in promoting the aggressive spread often seen in head and neck cancer. Tumor associated fibroblasts (TAFs) have also been implicated in facilitating angiogenesis and suppressing the normal anti-tumor function of immune cells. Studying the signaling molecules involved in these processes will facilitate the development of promising targets and inhibitors to prevent tumor-associated fibroblasts from exerting their reinforcing effects on the tumor. In this article, we review the recent literature on the signals used in tumor associated fibroblast communication, with a focus on potential therapeutic targets. Further, we highlight the lead candidates for TAF-targeted therapeutic interventions. Future anti-cancer strategies may achieve better results than current approaches by targeting the support cells in tumor stroma in addition to the cancerous cells.

Fluctuating roles of matrix metalloproteinase-9 in oral squamous cell carcinoma

One hallmark of cancer is the degradation of the extracellular matrix (ECM), which is caused by proteinases. In oral cancers, matrix metalloproteinases (MMPs), especially MMP-9, are associated with this degradation. MMPs break down the ECM allowing cancer to spread; they also release various factors from their cryptic sites, including cytokines. These factors modulate cell behavior and enhance cancer progression by regulating angiogenesis, migration, proliferation, and invasion. The development of early metastases is typical for oral cancer, and increased MMP-9 expression is associated with a poor disease prognosis. However, many studies fail to relate MMP-9 expression with metastasis formation. Contrary to earlier models, recent studies show that MMP-9 plays a protective role in oral cancers. Therefore, the role of MMP-9 is complicated and may fluctuate throughout the different types and stages of oral cancers.

Expression of matrix metalloproteinase 9 in patients with oral lichen planus

INTRODUCTION

Oral Lichen planus (OLP) is chronic inflammatory oral mucosal disease of unknown etiology. Basement membrane damage and T-cell migration in OLP may be mediated by matrix metalloproteinases (MMPs). We examined the expression of matrix metalloproteinase 9 to support this hypothesis.

MATERIALS AND METHODS

The study population consisted of 71 patients with OLP and 10 control patients with oral fibromas. Indirect immunohistochemistry was used for detection of MMP 9 expression (polyclonal rabbit anti-human MMP antibody).

RESULTS

In all cases of OLP, the MMP-9 expression was seen mainly in the area oflymphocytic inflammatory infiltrate in the lamina propria including lymphocytes within the overlying epithelium. In addition, it was observed in the epithelial keratinocytes, particularly in the stratum basale and stratum spinosum with occasional positivity in the superficial layer. Fibroblasts and endothelium of small vessels in the lamina propria showed MMP9 expression as well. In all cases of oral mucosal fibromas, the MMP-9 expression was seen only in fibroblasts and in endothelium of small vessels with occasional positivity within the overlying epithelium. It remains unclear, whether MMP-9 is directly connected to OLP pathogenesis.

Immunoexpression of matrix metalloproteinases and their inhibitors in different areas of oral squamous cell carcinoma

BACKGROUND

Several studies have shown the participation of MMPs in oral squamous cell carcinoma, the most frequent malignant neoplasm of the oral cavity. The expression of some MMPs correlates with a more aggressive biological behaviour. The objective of this study was to determine which MMPs and TIMPs were expressed in both neoplastic and peritumoural stromal cells in different histopathology areas.

METHODS

Patients who underwent primary tumour neck dissection for oral squamous cell carcinoma were included. Immunoexpression of MMP-1, -2, -3, -7, -9, -11, -13, and TIMP-1 and -2 in different areas of pathologic specimens (in situ carcinoma, primary tumour, invasive front, distant invasion carcinoma, and lymph node metastasis) was evaluated. Enzyme expression on mucosa adjacent to tumour served as control.

RESULTS

Thirty cases were included. Only 6 MMPs and 1 TIMP were expressed in the studied areas. Statistically significant differences in the number of cases with positive MMPs or TIMP expression, in both neoplastic and peritumoural cells, between control and the rest of the areas were observed. MMP-2 expression was constant in the areas with a more aggressive biological behaviour.

CONCLUSIONS

MMP-2 expression may represent a dynamic interaction between host and tumour that favours the establishment of neoplastic cells at distant sites.

CD147 and AGR2 expression promote cellular proliferation and metastasis of head and neck squamous cell carcinoma

The signaling pathways facilitating metastasis of head and neck squamous cell carcinoma (HNSCC) cells are not fully understood. CD147 is a transmembrane glycoprotein known to induce cell migration and invasion. AGR2 is a secreted peptide also known to promote cell metastasis. Here we describe their importance in the migration and invasion of HNSCC cells (FADU and OSC-19) in vitro and in vivo. In vitro, knockdown of CD147 or AGR2 decreased cellular proliferation, migration and invasion. In vivo, knockdown of CD147 or AGR2 expression decreased primary tumor growth as well as regional and distant metastasis.

Oral lichen planus as a preneoplastic inflammatory model

Oral lichen planus (OLP) is a chronic oral inflammatory disease of unknown etiology. According to reports, 1-2% of OLP patients develop oral squamous cell carcinoma (OSCC) in the long run. While World Health Organization (WHO) classifies OLP as “a potentially malignant disorder,” it is still a matter of debate which mechanisms drive OLP to such a condition. The current hypothesis connecting OLP and OSCC is that chronic inflammation results in crucial DNA damage which over time results in cancer development. Initial studies investigating the OLP and OSCC link were mainly retrospective clinical studies. Over the past years, several amount of information has accumulated, mainly from molecular studies on the OLP malignant potential. This article is a critical review of whether OLP has a malignant potential and, therefore, represents a model of preneoplastic inflammation.

Tissue inhibitor of metalloproteinases in oral squamous cell carcinomas - a therapeutic target?

Matrix metalloproteinases (MMPs) are proteases responsible for remodeling the extracellular matrix (ECM) and enabling spreading and metastasis of tumor cells, a common phenomenon in oral squamous cell carcinomas (OSCC). They are strongly blocked by several inhibitors, among which we must highlight, for their specificity and potency, the endogenous tissue inhibitors of metalloproteinases (TIMP-1, -2, -3 and -4). The goal of this paper is to describe the expression of TIMPs in OSCC, determining their relation with clinical, histological and prognostic factors, delving into OSCC regulation mechanisms and discussing the use of exogenous TIMPs to treat this type of tumors. Expression of TIMPs in OSCC is higher in tumors than in normal tissue, which correlates with an increase of metastatic risk and regional lymph node affectation. Although some metalloproteinases inhibitors (MMIs) have shown promising results in the treatment of these tumors, their use in OSCC has not been widely tested; and although some indirect MMIs, like COX-2 inhibitors, flavonoids and endostatin seem to have beneficial effects on the invasive capacity of OSCC through regulation of MMPs and TIMP levels, routine clinical use has not been accepted yet.

Serum level of matrix metalloproteinase-3 in patients with oral lichen planus

BACKGROUND

Oral Lichen planus (OLP) is a chronic lesion of the oral mucosa with unknown origin. Basement membrane changes are common in OLP and may be mediated by proteases such as matrix metalloproteinase (MMPs) and mast cell chymase. The aim of our study was to evaluate the level of serum MMP-3 in OLP com-pared to normal individuals and assess its clinical significance.

METHODS

Thirty four serum samples from patients diagnosed with OLP (12 males, 22 females, age: 42.2±10.8 years) and 34 serum samples from healthy control subjects (11 males, 23 females, age: 42.5±13.3 years) were collected and MMP-3 concentration was measured by ELISA.

RESULTS

The serum MMP-3 level in OLP patients was higher (21.64±24.31 ng/ml) compared with healthy con-trols (16.52±23.63 ng/ml), but showed no statistically significant difference. A statistically significant difference was demonstrated between the two types of OLP, being more pronounced in the erosive/atrophic form 6).

CONCLUSION

The different clinical appearances of OLP are associated with significant differences in MMP-3 serum level.

Regulation of survival, proliferation, invasion, angiogenesis, and metastasis of tumor cells through modulation of inflammatory pathways by nutraceuticals

Almost 25 centuries ago, Hippocrates, the father of medicine, proclaimed "Let food be thy medicine and medicine be thy food." Exploring the association between diet and health continues today. For example, we now know that as many as 35% of all cancers can be prevented by dietary changes. Carcinogenesis is a multistep process involving the transformation, survival, proliferation, invasion, angiogenesis, and metastasis of the tumor and may take up to 30 years. The pathways associated with this process have been linked to chronic inflammation, a major mediator of tumor progression. The human body consists of about 13 trillion cells, almost all of which are turned over within 100 days, indicating that 70,000 cells undergo apoptosis every minute. Thus, apoptosis/cell death is a normal physiological process, and it is rare that a lack of apoptosis kills the patient. Almost 90% of all deaths due to cancer are linked to metastasis of the tumor. How our diet can prevent cancer is the focus of this review. Specifically, we will discuss how nutraceuticals, such as allicin, apigenin, berberine, butein, caffeic acid, capsaicin, catechin gallate, celastrol, curcumin, epigallocatechin gallate, fisetin, flavopiridol, gambogic acid, genistein, plumbagin, quercetin, resveratrol, sanguinarine, silibinin, sulforaphane, taxol, gamma-tocotrienol, and zerumbone, derived from spices, legumes, fruits, nuts, and vegetables, can modulate inflammatory pathways and thus affect the survival, proliferation, invasion, angiogenesis, and metastasis of the tumor. Various cell signaling pathways that are modulated by these agents will also be discussed.

Matrix metalloproteinases and their inhibitors: correlation with invasion and metastasis in oral cancer

Matrix metalloproteinases (MMPs) have been implicated in invasion and metastasis of various malignancies. The study evaluated a comprehensive profile of MMP-2 and MMP-9 and their inhibitors, tissue inhibitor of metalloproteinases-2 (TIMP-2) and tissue inhibitor of metalloproteinases-1 (TIMP-1), respectively in 50 controls and 75 patients with oral squamous cell carcinoma (OSCC). Blood samples from controls and patients as well as malignant and adjacent normal tissues from the patients were collected. The study examined pro, active and total forms of MMP-2 and MMP-9 using zymography. Enzyme-linked immunoassay (ELISA) and reverse transcription polymerase chain reaction were carried out to evaluate protein levels and mRNA expression; respectively, for the MMPs and TIMPs. Plasma pro, active and total MMP-2, MMP-9 as well as TIMP-1 and TIMP-2 levels were significantly higher in oral cancer patients as compared to the controls. mRNA expression of the MMPs and TIMPs was significantly higher in malignant tissues as compared to adjacent normal tissues. A significant positive correlation was observed between levels of proMMP-9 and active MMP-9 with differentiation, stage and infiltration. ProMMP-2 and active MMP-2 exhibited significant positive correlation with differentiation and lymph node involvement. The multivariate analysis of ELISA results revealed a significant positive correlation between MMP-2, TIMP-1 and TIMP-2 levels with lymph node involvement, stage and differentiation. The receiver operating characteristic curve (ROC) analysis showed that the levels of MMPs and TIMPs have significant discriminatory efficacy to differentiate between controls and patients. The results indicate that MMP-2, MMP-9, TIMP-1 and TIMP-2 have significant clinical usefulness for oral cancer patients. Zymographic analysis is a simple, cost effective, rapid and sensitive alternative assay.

Glycogen synthase kinase 3 beta: can it be a target for oral cancer

Despite progress in treatment approaches for oral cancer, there has been only modest improvement in patient outcomes in the past three decades. The frequent treatment failure is due to the failure to control tumor recurrence and metastasis. These failures suggest that new targets should be identified to reverse oral epithelial dysplastic lesions. Recent developments suggest an active role of glycogen synthase kinase 3 beta (GSK3 β) in various human cancers either as a tumor suppressor or as a tumor promoter. GSK3β is a Ser/Thr protein kinase, and there is emerging evidence that it is a tumor suppressor in oral cancer. The evidence suggests a link between key players in oral cancer that control transcription, accelerated cell cycle progression, activation of invasion/metastasis and anti-apoptosis, and regulation of these factors by GSK3β. Moreover, the major upstream kinases of GSK3β and their oncogenic activation by several etiological agents of oral cancer support this hypothesis. In spite of all this evidence, a detailed analysis of the role of GSK3β in oral cancer and of its therapeutic potential has yet to be conducted by the scientific community. The focus of this review is to discuss the multitude of roles of GSK3β, its possible role in controlling different oncogenic events and how it can be targeted in oral cancer.

A basal-cell-like compartment in head and neck squamous cell carcinomas represents the invasive front of the tumor and is expressing MMP-9

Head and neck squamous cell carcinomas (HNSCCs) are the most frequent malignancies of the upper aerodigestive tract. The cancer stem cell (CSC) hypothesis concludes that CSCs constitute the dangerous tumor cell population due to their ability of self-renewal and being associated with relapse of tumor disease, invasiveness and resistance to chemo(radio)therapy. The aim of this study was to look for CSC candidates and expression of MMP-9 that previously was implicated in HNSCC invasiveness. Immunohistochemical, immunofluorescence and Western blot analysis were performed on HNSCC tumor specimens using antibodies specific for MMP-9, CD44, ALDH1 and CK14. Gelatinolytic activity was assessed by zymography. Pearson correlation analysis was used for statistical comparison. Immunohistochemical analysis found CD44 and MMP-9 to co-localize in tumor cells at the invasive front. Western blot analysis demonstrated a significant correlation (p=0.0047) between CD44 and MMP-9 in the tested tissues. In addition gelatinolytic activity of HNSCC tissues was found to significantly correlate (p=0.0010) with MMP-9 expression. The CD44(+) invasive front of the tumor was also positive for ALDH1 and CK14, all of them being typically expressed by cells in the basal cell layer of normal stratified squamous epithelia that also harbors the epithelial stem cells. The observations point to a role of a MMP-9 positive basal-cell-like cell layer in the process of HNSCC invasiveness. This compartment likely contains CSCs since it is expressing the putative CSC markers CD44, ALDH1 and CK14. This cell layer therefore should be considered a major therapeutic target in the treatment of head and neck cancer.

[Analysis of TIMP-1, TIMP-2 and TIMP-3 expression as a prognostic factor of laryngeal cancer progression]

INTRODUCTION

Tissue inhibitors of matrix metalloproteinases (TIMPs) are natural regulator of activity of matrix metalloproteinases, that are responsible for ECM degradation. TIMPs have been identified in various carcinomas and in most of them dependence between TIMPs and clinical course of the disease have been observed.

AIM

Of the research was to evaluate expression of TIMP-1, TIMP-2 and TIMP-3 in laryngeal cancer and to asses the prognostic significance of these factors.

MATERIAL AND METHOD

104 patients with laryngeal cancer, that underwent surgical treatment were included in the study. Only cases with at least a 5-year follow-up were included. Immunohistochemical studies were performed on formalin fixed, paraffin embedded sections by using monoclonal antibodies against TIMP-1, -2 and -3 antigens and ABC detection system. Results. TIMPs expression was cytoplasmatic, mainly in cancer cells, but also in some stromal cells. TIMP-1 and TIMP-2 correlated with grading (TIMP-1 p = 0,05; TIMP-2 p = 0,001). There was an association between TIMP-2 and TIMP-3 expression and tumor size (TIMP-2 p = 0,037; TIMP-3 p = 0,022). TIMP-3 expression correlated with clinical stage of the disease (p = 0,037). There was an association between TIMP-2 expression and nodal recurrence (p = 0,05). Both overall and disease-free survival were shorter in cases with positive TIMP-2 expression (p = 0,049).

CONCLUSIONS

Our results demonstrate that there is an association between TIMPs expression and clinicopathological features of laryngeal cancer. Moreover TIMP-2 could be an important marker in prognosis of laryngeal cancer patients.

Active matrix metalloproteinase-7 is associated with invasion in buccal squamous cell carcinoma

Protein microarrays have shown that matrix metalloproteinase-7 is upregulated in head and neck squamous cell carcinomas, but its role in local tissue invasion is still uncertain. We investigated the expression of active matrix metalloproteinase-7, using tissue microarray, immunohistochemistry, and western blotting, in oral tissues from 24 patients with buccal squamous cell carcinoma, and correlated the findings with clinicopathological features. Normal buccal tissue samples from the same patients, obtained at sites at least 1 cm from tumor tissue, served as normal controls. Total matrix metalloproteinase-7 was detected on western blots in 9 of 15 (60%) tumor tissue samples and in 2 of 15 (13%) normal mucosal samples; this difference was significant (P=0.008). Moreover, the active matrix metalloproteinase-7 was expressed only in eight of the nine (89%) tumor samples that expressed matrix metalloproteinase-7, and in none of the normal tissue samples, regardless of the expression status of the pro-matrix metalloproteinase-7. Immunostaining of matrix metalloproteinase-7 was observed histologically in both tumor and nonneoplastic epithelium, but immunostaining of active matrix metalloproteinase-7 was present only in tumor nests. Expression of active matrix metalloproteinase-7 was associated with larger tumor size (P=0.022) and was significantly higher in buccal squamous cell carcinoma with adjacent skin or bone invasion (P=0.036). In conclusion, active matrix metalloproteinase-7 expression was associated with more aggressive buccal squamous cell carcinomas.

Endostar Suppresses Invasion Through Downregulating the Expression of Matrix Metalloproteinase-2/9 in MDA-MB-435 Human Breast Cancer Cells

Endostar, a novel recombinant human endostatin expressed and purified in Escherichia coli with an additional nine-amino acid sequence forming another his-tag structure, was approved by the State Food and Drug Administration of China (SFDA) in 2005 for the treatment of non-small-cell lung cancer. However, the molecular mechanism of its potent anticancer activity remains poorly understood and warrants further investigations. In this study, we examined the anti-invasive activities of endostar in vitro. The results showed that endostar suppressed MDA-MB-435 cell adhesion to the fibronectin-coated substrate in a concentration-dependent manner. It could inhibit the wound healing migration of MDA-MB-435 cells and invasion of MDA-MB-435 cells through reconstituted ECM (matrigel). Zymography revealed that endostar decreased the secretion of MMP-2 and MMP-9. Endostar could also inhibit the expressions of MMP-2 and MMP-9 in MDA-MB-435 cells. Additionally, endostar exerted an inhibitory effect on the phosphorylation of ERK1/2. Collectively, these data provided a molecular basis for the anti-invasive effects of endostar.

Rap1GAP promotes invasion via induction of matrix metalloproteinase 9 secretion, which is associated with poor survival in low N-stage squamous cell carcinoma

The objective of the current study was to investigate the effects of Rap1GAP on invasion and progression of head and neck squamous cell carcinoma (SCC) and the role of matrix metalloproteinase (MMP) 9 and MMP2 in this process. Rap1GAP functions by switching off Rap1, the Ras-like protein that has been associated with carcinogenesis. Previous findings suggest that Rap1GAP acts as a tumor suppressor protein in SCC by delaying the G(1)-S transition of the cell cycle. However, cells transfected with Rap1GAP exhibit a more invasive phenotype than corresponding vector-transfected control cells. MMP2 and MMP9 are enzymes that mediate SCC invasion via degradation of the extracellular matrix. Using SCC cells transfected with empty vector or Rap1GAP, cell invasion and MMP secretion were determined by Matrigel assays and gelatin zymography, respectively. Rap1GAP up-regulated transcription and secretion of MMP2 and MMP9, as assayed by quantitative reverse transcription-PCR and zymography. Furthermore, chemical and RNA interference blockade of MMP2/MMP9 inhibited invasion by Rap1GAP-transfected cells. Immunohistochemical staining of a human oropharyngeal SCC tissue microarray showed that Rap1GAP and MMP9 expression and staining intensity are correlated (P < 0.0001) and that, in early N-stage lesions of SCC, high MMP9 is prognostic of poor disease-specific survival (P < 0.05). Furthermore, Rap1GAP staining is correlated with MMP2 (P < 0.03). MMP2 in combination with N stage has a prognostic effect on time to indication of surgery at primary site. MMP2 intensity is also positively correlated with T stage (P < 0.015). In conclusion, Rap1GAP inhibits tumor growth but induces MMP2- and MMP9-mediated SCC invasion and tumor progression, suggesting a role for this protein as a biomarker for early N-stage, aggressive SCCs.

[Assessment of tissue inhibitor of metalloproteinases-2 (TIMP-2) in laryngeal cancer]

Metalloproteinases are the proteolytic enzymes that digest components of the extracellular matrix in many physiological and pathological conditions. Their activity is regulated by their natural inhibitors: non-specific alpha2-macroglobulin and specific tissue inhibitors of metalloproteinases (TIMP). There are four TIMPs. TIMP-2 is the only enzyme that is expressed in constitutive manner and has the ability to inhibit activity of all metalloproteinases. TIMP-2 has been identified in many carcinomas including cancers of lung, oral cavity, breast and colon. There was correlation between TIMP-2 expression and clinical course of the disease observed in most of the neoplasm.

AIM

The aim of the research was to evaluate the expression of TIMP-2 in laryngeal cancer and to assess the prognostic significance of this factor.

MATERIAL AND METHOD

104 patients with laryngeal cancer, that underwent surgical treatment were included in the study. Only cases with at least a 5-year follow-up were included. Immunohistochemical studies were performed on formalin fixed, paraffin embedded sections by using monoclonal antibodies against TIMP-2 antigen and ABC detection system.

RESULTS

TIMP-2 expression was cytoplasmatic, mainly in cancer cells, but also in some stromal cells. There was correlation between TIMP-2 expression and tumor size and grading observed. We didn't find any correlation between TIMP-2 and nodal metastases, recurrence and survival.

CONCLUSIONS

Our results don't suggest that TIMP-2 expression may be used as a prognostic factor in patients with laryngeal cancer. Nevertheless there are more researches needed to explain the role of TIMPs in growth and progression of neoplastic tumors.