Expressions of matrix metalloproteinases in early-stage oral squamous cell carcinoma as predictive indicators for tumor metastases and prognosis

In vitro and in vivo inhibition of human Fanconi anemia head and neck squamous carcinoma by a phytonutrient combination

Head and neck squamous cell carcinoma (HNSCC) and acute myeloid leukemia are the major causes of mortality and morbidity in Fanconi anemia (FA) patients. The objective of this study was to investigate the antineoplastic activity of PB, an antineoplastic nutrient mixture (containing quercetin, curcumin, green tea, cruciferex and resveratrol) on human FA HNSCC in vitro and in vivo. Human FA HNSCC cell line OHSU-974 (Fanconi Anemia Research Fund) was cultured in RPMI medium supplemented with 20% FBS and anti-biotics. At near confluence, cells were treated in triplicate with different concentrations of PB: 0, 10, 25, 50, 75 and 100 µg/ml. Cells were also treated with PMA to induce MMP-9 activity. Cell proliferation was detected by MTT assay, secretion of MMPs by gelatinase zymography, invasion through Matrigel, migration by scratch test and morphology by hematoxylin and eosin (H&E) staining. In vivo, athymic male nude mice (n=12) were inoculated with 3x106 OHSU-974 cells subcutaneously and randomly divided into two groups: group A was fed a regular diet and group B a regular diet supplemented with 1% PB. Four weeks later, the mice were sacrificed and their tumors were excised, weighed and processed for histology. NM inhibited the growth of OHSU-974 tumor by 67.6% (p<0.0001) and tumor burden by 63.6% (p<0.0001). PB demonstrated dose-dependent inhibition of cell proliferation, with 27% (p=0.0003) and 48% (p=0.0004) toxicity at 75 and 100 µg/ml, respectively. Zymography revealed MMP-2 and PMA-induced MMP-9 secretion. PB suppressed secretion of both MMPs in a dose-dependent manner, with total block of both at 50 µg/ml. PB inhibited cell migration (by scratch test) and OHSU-974 invasion through Matrigel in a dose-dependent fashion with total block at 50 µg/ml. H&E staining showed no morphological changes below 50 µg/ml. The results suggest that PB has potential therapeutic use in the treatment of human FA HNSCC.

Characteristics of Expression of Matrix Metalloproteinases (MMP-2 and MMP-9) in Glottic Squamous Cell Carcinoma and Benign Vocal Fold Lesions

Objectives

The aim of this study was to investigate expression profile of matrix metalloproteinases (MMP-2 and MMP-9) in glottic squamous cell carcinoma (SCC) and benign vocal fold lesions (BVFLs) and to correlate it with clinical and pathological features.

Methods

The immunohistochemical expression of MMP-2 and MMP-9 was investigated in specimens taken from 217 patients group, including vocal fold polyps (n=39), recurrent respiratory papillomatosis (n=30), laryngeal keratosis (n=36), glottic SCC (n=112), and the normal tissue of vocal fold (n=12, control group). The expression of MMP-2 and MMP-9, both in epithelium and stroma cells, was graded on a semiquantitative scale, ranging from 0 (no expression) to 18 points (high expression).

Results

Expressions of both, MMP-2 and MMP-9 were significantly higher in the glottic SCC group comparing with BVFL group. Significant higher expression of parenchymal MMP-2 (P<0.001) and stromal MMP-9 (P=0.01) was revealed in the group of moderate/poorly differentiated glottic SCC comparing with well differentiated glottic SCC group. Expression of stroma MMP-2 was found to be correlated with nodal metastasis (P=0.030). Expressions of both, MMP-2 and MMP-9 were not correlated with clinical stage, tumor T value, smoking, alcohol use, age in the glottic SSC patients group. The MMP-2 stroma value of 11.2 points was determined as the optimum point (limiting value) for separating BVFL and glottic SCC patient groups.

Conclusion

Our results suggest that expressions of both MMP-2 and MMP-9 are up-regulated already in the development of BVFL, the next determinant step is concerned with occurrence of malignization. Limiting value of stroma MMP-2 demonstrates prognostic importance of MMP-2 in glottic SCC carcinogenesis.

Prognostic value of matrix metalloproteinases in oral squamous cell carcinoma

The aim of this study was to investigate whether there is a correlation between the expressions of four matrix metalloproteinases (MMPs): MMP-2, MMP-7, MMP-9 and MMP-13, and the TNM (tumour–node–metastasis) stages of oral squamous cell carcinoma (OSCC); and to explore the implication of these MMPs in OSCC dissemination. Samples from 61 patients diagnosed with oropharyngeal tumour were studied by immunohistochemistry against MMP-2, MMP-7, MMP-9 and MMP-13. The assessment of immunoreactivity was semi-quantitative. The results showed that MMP-2 and MMP-9 had similar expression patterns in the tumour cells with no changes in the immunoreactivity during tumour progression. MMP-9 always had the highest expression, whereas that of MMP-2 was moderate. MMP-7 showed a significant decrease in expression levels during tumour evolution. MMP-13 had constant expression levels within stage T2 and T3, but showed a remarkable decline in immunoreactivity in stage T4. No significant differences in the MMPs immunoreactivity between tumour cells and stroma were observed. Although strong evidence for the application of MMPs as reliable predictive markers for node metastasis was not acquired, we believe that combining patients’ MMPs expression intensity and clinical features may improve the diagnosis and prognosis. Strong evidence for the application of MMPs as reliable predictive markers for node metastasis was not acquired. Application of MMPs as prognostic indicators for the malignancy potential of OSCC might be considered in every case of tumour examination. We believe that combining patients’ MMPs expression intensity and clinical features may improve the process of making diagnosis and prognosis.

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.

Decreased expression of the long non-coding RNA FENDRR is associated with poor prognosis in gastric cancer and FENDRR regulates gastric cancer cell metastasis by affecting fibronectin1 expression

BACKGROUND

FENDRR is a long non-coding RNAs (lncRNA) that binds to polycomb repressive complexe 2 (PRC2) to epigenetically regulate the expression of its target gene. The clinical role of FENDRR in carcinomas remains yet to be found.

METHOD

Real-time polymerase chain reaction (PCR) was used to examine FENDRR expression in gastric cancer cell lines/tissues compared with normal epithelial cells/adjacent non-tumorous tissues. Cell proliferation assays, Wound healing assays, and in vitro and in vivo invasion and migration assays were performed to detect the biological effects of FENDRR in gastric cancer cells. Real-time PCR, western-blot and immunohistochemistry were used to evaluate the mRNA and protein expression of fibronectin1 (FN1). Secreted matrix metalloproteinase (MMP) activities were detected and characterized using gelatin zymography assay.

RESULTS

FENDRR was downregulated in gastric cancer cell lines and cancerous tissues, as compared with normal gastric epithelial cells and adjacent noncancerous tissue samples. Low FENDRR expression was correlated with deeper tumor invasion (p < 0.001), higher tumor stage (p = 0.001), and lymphatic metastasis (p = 0.007). Univariate and multivariate analyses indicated that low FENDRR expression predicted poor prognosis. Histone deacetylation was involved in the downregulation of FENDRR in gastric cancer cells. FENDER overexpression suppressed invasion and migration by gastric cancer cells in vitro, by downregulating FN1 and MMP2/MMP9 expression.

CONCLUSION

Low expression of the lncRNA FENDRR occurs in gastric cancer and is associated with poor prognosis. Thus, FENDRR plays an important role in the progression and metastasis of gastric cancer.

The cytoplasmic domain of N-cadherin modulates MMP‑9 induction in oral squamous carcinoma cells

Oral squamous carcinoma is the sixth most common cancer worldwide, and one of the most common cancers in developing countries. Regional and distant metastases comprise the majority of cases at initial diagnosis and correlate with poor patient outcomes. Oral epithelia is one of many tissue types to exhibit a cadherin switch during tumor progression, in which endogenous cell adhesion proteins, such as E-cadherin, give way to those of mesenchymal origin. The mesenchymal cell adhesion protein N-cadherin is found at the invading front of oral squamous carcinomas and has been strongly correlated with poor patient prognosis. The goal of the present study was to elucidate the mechanism by which N-cadherin may increase extracellular matrix-associated proteolytic activity to facilitate invasiveness in oral tumor development. The overexpression of N-cadherin in two oral squamous carcinoma cell lines increased motility, invasive capacity and synthesis of matrix metalloproteinase-9 (MMP-9) in a manner that was independent of E-cadherin downregulation. The use of EN and NE chimeric cadherin molecules with reciprocally substituted cytoplasmic domains revealed that optimal induction of MMP-9 synthesis required the cytoplasmic region, but not the extracellular region, of N-cadherin. Utilizing an N-cadherin mutant with impaired p120 binding ability, we found that such mutation resulted in a 4-fold decrease in motility compared to wild-type N-cadherin, but did not affect either MMP-9 expression or motility-normalized invasion. Overexpression of wild-type N-cadherin produced a 27-fold increase in the transcriptional activity of β-catenin, concomitant with increases in MMP-9 transcription. These results suggest that N-cadherin may promote motility and invasiveness through distinct mechanisms, and that β-catenin may be an integral mediator of N-cadherin-dependent invasive signaling in oral epithelia.

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.

Expression of metalloproteinases 2 and 9 and tissue inhibitors 1 and 2 as predictors of lymph node metastases in oropharyngeal squamous cell carcinoma

BACKGROUND

The matrix metalloproteinases (MMPs) and their tissue inhibitor of metalloproteinases (TIMPs) can decompose extracellular matrix (ECM) components and brake down basement membranes and, thus, promote tumor local invasion and metastasis.

METHODS

We studied 41 patients with squamous cell carcinoma (SCC) of the oropharynx who underwent surgical treatment. Material was diagnosed by routine procedure and examined by immunohistochemical analysis and dot blot technique. We searched for correlations between expressions of MMPs, such as MMP-2 and MMP-9 and their tissue inhibitors TIMP-1 and TIMP-2 and treatment outcome.

RESULTS

We found cytoplasmic expression of analyzed proteins, both in cancer cells and tumor stroma. The expression of analyzed antigens was higher in patients with lymph node metastases comparing patients without lymph node involvement.

CONCLUSION

Our data suggest that microenvironment changes are one of key factors in tumor progression. Divergent expression of MMPs and their inhibitors might be used as prognostic factor of oropharyngeal carcinoma progression.

Activation of Toll-like receptor-9 promotes cellular migration via up-regulating MMP-2 expression in oral squamous cell carcinoma

PURPOSE

Activation of Toll like receptors (TLRs) signaling has been implicated in promoting malignant cell invasion and metastatic potential. Previously we demonstrated that increased TLR-9 expression predicted poor survival in oral cancer patients. The objective of this study is to further investigate the roles and potential molecular mechanisms of TLR-9 signaling in human oral cancer cell invasion.

METHODS

Cell migration, invasion and protein expression were detected by wound healing assay, Transwell chambers model and western blot. The secretion and activity levels of metalloproteinases-2/9 were quantified by ELISA and Gelatin zymography. EMSA and ChIP assays were employed to detect the activity of AP-1signal pathway. TLR-9 siRNA transfection was used to regulate the expression and activity of TLR-9 in oral cancer cell line HB cells.

RESULT

The results of both wound healing assay and in vitro Transwell assay revealed that activation of TLR-9 induced dose- and time- dependent migration and invasion of HB cells. An increased expression, secretion and activity of MMP-2 were observed upon the treatment of CpG-ODN. The TLR-9 signaling-mediated MMP-2 expression appeared to be a consequence of AP-1 activation, because that their DNA binding activity was enhanced by CpG-ODN treatment. All these influences were efficiently repressed by the knockdown of TLR-9 through siRNA or pretreatment of an AP-1 inhibitor.

CONCLUSION

Activation of TLR-9 signaling could promote human oral cancer HB cells invasion with the induction of MMP-2 presentation by attenuating AP-1 binding activity, suggesting a novel anti-metastatic application for TLR-9 targeted therapy in oral cancer in the future.

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.

Interferon-β Delivery via Human Neural Stem Cell Abates Glial Scar Formation in Spinal Cord Injury

Glial scar formation is the major impedance to axonal regrowth after spinal cord injury (SCI), and scar-modulating treatments have become a leading therapeutic goal for SCI treatment. In this study, human neural stem cells (NSCs) encoding interferon-β (INF-β) gene were administered intravenously to mice 1 week after SCI. Animals receiving NSCs encoding IFN-β exhibited significant neurobehavioral improvement, electrophysiological recovery, suppressed glial scar formation, and preservation of nerve fibers in lesioned spinal cord. Systemic evaluation of SCI gliosis lesion site with lesion-specific microdissection, genome-wide microarray, and MetaCore pathway analysis identified upregulation of toll-like receptor 4 (TLR4) in SCI gliosis lesion site, and this led us to focus on TLR4 signaling in reactive astrocytes. Examination of primary astrocytes from TLR4 knockout mice, and in vivo inhibition of TLR4, revealed that the effect of IFN-β on the suppression of glial scar formation in SCI requires TLR4 stimulation. These results suggest that IFN-β delivery via intravenous injection of NSCs following SCI inhibits glial scar formation in spinal cord through stimulation of TLR4 signaling.

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.

Aberrant expression of clock gene period1 and its correlations with the growth, proliferation and metastasis of buccal squamous cell carcinoma

Period1 (PER1) is an important core clock gene, which regulates normal cell proliferations and physiological rhythms of human beings. Recent studies have showed aberrant expressions and altered rhythms of PER1 were highly correlated to the carcinogenesis and development of malignant tumors. However, there is no study on the correlation of aberrant expressions and altered rhythms of PER1 with the growth, proliferation and metastasis of buccal squamous cell carcinoma (BSCC). In this study, PER1 and MMP-2 expression in the cancerous and adjacent noncancerous tissues of 38 patients with BSCC and its correlations with patients' clinical pathologic characteristics were investigated. A mouse model of BSCC was also established and mice were sacrificed at 4 different time points in a period of 24 hours. Xenografted tumor weight, proliferation index (PI), and mitotic index (MI) of tumors in the 4 time groups were detected. Results showed that PER1 expression was significantly down-regulated in cancerous tissues of patients with BSCC (P<0.05). PER1 expression was significantly down-regulated in patients of T3∼T4 staging and those with lymph node metastasis compared to that of T1∼T2 staging and those without lymph node metastasis (P<0.05), respectively. PER1 mRNA expression, MI and tumor weight had significant differences among the 4 time groups, which PI all confirmed to circadian rhythms. MI, PI, MMP-2 mRNA and tumor weight had negative correlation with PER1 mRNA expression. Peak value of PER1 mRNA expression and trough values of MI, PI and tumor weight all appeared in middle activity phase, whereas trough value of PER1 mRNA expression and peak values of MI, PI and tumor weight all occurred in middle rest phase. Our study suggested that aberrant expression of PER1 had significant correlation with the growth, proliferation and metastasis of BSCC and it might act as an anti-oncogene.

Calreticulin, an endoplasmic reticulum-resident protein, is highly expressed and essential for cell proliferation and migration in oral squamous cell carcinoma

OBJECTIVES

Oral squamous cell carcinoma (OSCC) has emerged as one of the major malignant tumors of the head and neck cancers. However, the molecular mechanism behind tumorigenesis of OSCC is not fully understood. The aim of this study was to investigate the role of calreticulin (CRT), an endoplasmic reticulum-resident protein, in OSCC cells.

MATERIALS AND METHODS

Sixteen paired samples of tumor and non-cancerous matched tissue (NCMT), six OSCC cell lines and normal human oral keratinocytes (NHOKs), and oral tissue microarray were used to reveal the expression of CRT by Western blotting and immunohistochemistry. Later, shRNA-mediated stable knockdown of CRT in OSCC cells was generated. The knockdown cell line was used to analyze cell proliferation, colony formation, anchorage-independent growth and cell migration in vitro.

RESULTS

CRT was differentially expressed in fresh tumor samples and six OSCC cell lines but not adjacent NCMTs and NHOKs. In oral tissue microarray, we showed that there was positive CRT staining in the vast majority of tumor cases (99/103), in sharp contrast to that in NCMT cases (29/92) (p<0.001). Stable knockdown of CRT in oral cancer cells resulted in significantly reduced growth rate, colony-forming capacity and anchorage-independent growth. This may be attributed to the induction of G0/G1 cell cycle arrest when CRT was depleted in the cells. Both horizontal and vertical movements of the CRT-knockdown stable line were markedly impaired. The phosphorylation levels of focal adhesion kinase (FAK), paxillin and ERK1/2 and the activity of matrix metalloproteinase-2 and -9 (MMP-2 and MMP-9) were decreased in the CRT-knockdown cells. These results suggest that CRT can regulate oral cancer cell migration through activation of the FAK signaling pathway accompanied with proteolytic degradation of the extracellular matrix (ECM) by MMP-2 and MMP-9.

CONCLUSION

Together, this study has defined a novel biological role for CRT in oral cancer. CRT is a potential biomarker and may contribute to the malignant phenotypes of OSCC cells.

Matrix metalloproteinase and its drug targets therapy in solid and hematological malignancies: an overview

Matrix metalloproteinase (MMP) comprises a family of zinc-dependent endopeptidases that degrade various components of the extracellular matrix (ECM) and basement membrane. MMPs are involved in solid and hematological malignancy through modification of cell growth, activation of cancer cells and modulation of immune functions. Several polymorphisms of different MMPs such as MMP-1 (-1607 1G/2G), MMP-2 (-1306 C/T), MMP-3 (-1171 5A/6A) & MMP-9 (-1562 C/T) and their expression levels have been well documented in different types of solid cancer. These polymorphic variations were found to be associated with angiogenesis, cancer progression, invasion and metastasis. There is paucity of data available in the field of hematological malignancies. Hence the field of matrix biology of hematological malignancies is an area of active exploration. A number of MMP inhibitors (MMPIs) have been developed for the cancer treatment. The most extensively studied classes of MMP inhibitors include Batimastat, Marismastat, Salimatat, Prinomastat and Tanomastat. However, their efficacy and action have not been confirmed and more data is required. The application of one or more selective targeted MMPIs in combination with conventional anti-leukemic treatment may represent a positive approach in combat against hematopoietic malignancies. Balance of MMPs and TIMPs is altered in different malignancies and biochemical pathways. These alternations will add another dimension in the matrix biology of both solid tumor and leukemia. MMP and TIMP singly and in combination are increasingly being recognized as an important player in basic cellular biology. Exploration and exploitation of MMP and TIMP balance in various malignant and nonmalignant lesions is going to be one of the most interesting facets of future use of this system for human health care.

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.

Matrix metalloproteinase-2 as a target for head and neck cancer therapy

INTRODUCTION

Matrix metalloproteinase (MMP)-2 is a zinc-dependent proteinase that is capable of cleaving all extracellular matrix (ECM) substrates. Degradation of the matrix is a key event in the progression, invasion, and metastasis of potentially malignant and malignant lesions of the head and neck. Therefore, blocking MMP-2 expression or activity may present a promising strategy for anticancer treatment.

AREAS COVERED

Current understanding of the molecular mechanisms that govern MMP-2 regulation and its tumorigenic effects, and that are involved in the initiation and progression of head and neck cancers, in particular the emerging role of MMP-2 in cell migration, which is a prerequisite for tumor metastasis. MMP-2 gene polymorphisms, cellular substrates, and interacting proteins are summarized. The current state of drugs that target this enzyme, either alone or in combination with other targeted agents are also discussed.

EXPERT OPINION

MMP-2 has long been a drug target. The current status of MMP-2 inhibitors as anticancer agents and their failure in the clinic is discussed in light of new data on the MMP-2s role as a cell surface transducer - data that may lead to the design and development of novel, MMP-2-targeting inhibitors.

Caffeic Acid phenethyl ester inhibits oral cancer cell metastasis by regulating matrix metalloproteinase-2 and the mitogen-activated protein kinase pathway

Caffeic acid phenethyl ester (CAPE), an active component extracted from honeybee hives, exhibits anti-inflammatory and anticancer activities. However, the molecular mechanism by which CAPE affects oral cancer cell metastasis has yet to be elucidated. In this study, we investigated the potential mechanisms underlying the effects of CAPE on the invasive ability of SCC-9 oral cancer cells. Results showed that CAPE attenuated SCC-9 cell migration and invasion at noncytotoxic concentrations (0 μM to 40 μM). Western blot and gelatin zymography analysis findings further indicated that CAPE downregulated matrix metalloproteinase-2 (MMP-2) protein expression and inhibited its enzymatic activity. CAPE exerted its inhibitory effects on MMP-2 expression and activity by upregulating tissue inhibitor of metalloproteinase-2 (TIMP-2) and potently decreased migration by reducing focal adhesion kinase (FAK) phosphorylation and the activation of its downstream signaling molecules p38/MAPK and JNK. These data indicate that CAPE could potentially be used as a chemoagent to prevent oral cancer metastasis.

Matrix metalloproteinase gene polymorphisms and oral cancer

Since oral squamous cell carcinoma (OSCC) is the most prevalent malignant cancer in the oral cavity, several researches have been performed to study the role of important enzymes in this disease. Among them, the matrix metalloproteinases (MMPs) are highlighted, due to the fact that they are proteinases responsible to degrade many extra-cellular matrix components, making possible the invasion of neoplasic cells. Important tools in cancer prognosis have been utilized aiming to correlate high levels of MMPs and OSCC, such as immunohistochemical, zymographic and mRNA detection methods. However, these techniques are usually applied after cancer detection, characterizing a curative but not a preventive medicine. Trying to make interventions before the development of the disease and making possible the identification of people at high risk and, analysis of modifications in MMP genes has been a chance for modern medicine. Recently, polymorphisms in MMP genes have been related to different neoplasias, including OSCC. Despite investigation is beginning, MMP gene polymorphisms seems to have a promising future in oral cancer research and some of the present results have shown that there are MMP polymorphisms related to an increased risk for developing oral cancer. Key words:Oral cancer, polymorphism, matrix metalloproteinase.

Prognostic role of MMP-9 expression in head and neck carcinoma patients treated with radiotherapy or chemoradiotherapy

OBJECTIVES

The purpose of this study was to evaluate the prognostic significance of the expression of metalloproteinases (MMPs)-2 and -9 at a transcriptional level in patients with head and neck squamous cell carcinoma (HNSCC).

PATIENTS AND METHODS

Real-time polymerase chain reaction was used to determine mRNA expression levels of MMP-2 and MMP-9 in 105 consecutive patients with HNSCC treated with radiotherapy or chemoradiotherapy. Continuous values of mRNA expression levels were analyzed using a classification and regression tree (CART) method.

RESULTS

Patients were grouped into two categories according to the results from CART analysis; high (n=71) and low (n=34) expression levels of MMP-9. MMP-2 expression was not included in the model. The 5-year adjusted survival rate was 92.9% for patients with low MMP-9 expression level and 61.0% for patients with a high expression level (P=0.006). Overexpression of MMP-9 was associated with a decrease in local control of the disease. In a multivariate analysis, MMP-9 expression was the only variable that was associated with adjusted survival. Considering patients with a low MMP-9 expression level as the reference group, patients with a high MMP-9 expression level had a 6.1 times higher risk of death from HNSCC (CI 95%: 1.4-26.4).

CONCLUSION

We found a significant relationship between the transcription of MMP-9 and adjusted survival in HNSCC patients treated with radiotherapy or chemoradiotherapy. These results suggest that MMP-9 transcription may serve as a marker of treatment response to radiotherapy or chemo-radiotherapy in patients with HNSCC.

Immunohistochemical expression of MMP-9 and VEGF in squamous cell carcinoma of the tongue

Squamous cell carcinomas (SCCs) account for approximately 95% of all oral malignant neoplasms and for about 38% of all malignant head and neck tumors, especially affecting the tongue and lips. The aim of this study was to evaluate the immunohistochemical expression of MMP-9 and VEGF in oral SCC according to the occurrence of metastasis. Eighteen cases of tongue SCC without metastases and 17 cases of tongue SCC with metastases were subjected to immunohistochemical methods. High immunohistochemical expression of MMP-9 and VEGF by neoplastic cells and stroma was observed in tongue SCCs at the invasion front. Metastatic tumors tended to express higher levels of MMP-9 and VEGF than non-metastatic tumors, but the difference was not significant (P > 0.05). Spearman's correlation test showed no significant correlation between VEGF-immunopositive vessels and metastasis (P > 0.05). The present results demonstrate the importance of the expression of MMP-9 and VEGF for the development of SCC of the tongue. However, no significant association was observed between the overexpression of MMP-9 or VEGF and the presence of metastases.

In vitro and in vivo inhibition of human Fanconi anemia-associated head and neck squamous cell carcinoma by a novel nutrient mixture

Head and neck squamous cell carcinoma (HNSCC) and acute myeloid leukemia are the major causes of mortality and morbidity in Fanconi anemia (FA) patients. The objective of this study was to investigate the antineoplastic activity of a novel antineoplastic nutrient mixture (NM) (containing lysine, proline, ascorbic acid and green tea extract) in human FA-associated HNSCC (FA HNSCC) in vitro and in vivo. The human FA HNSCC cell line, OHSU-974 (Fanconi Anemia Research Fund), was cultured in RPMI medium supplemented with 20% FBS and antibiotics. At near confluence, cells were treated in triplicate with various concentrations of NM: 0, 50, 100, 250, 500 and 1,000 μg/ml. Cells were also treated with phorbol 12-myristate 13-acetate (PMA) to induce matrix metalloproteinase (MMP)-9 activity. Cell proliferation was detected by MTT assay, the secretion of MMPs by gelatinase zymo graphy, cell invasion through Matrigel, cell migration by a scratch test and morphology by hematoxylin and eosin (H&E) staining. In vivo, athymic male nude mice (n=12) were inoculated with 3×10⁶ OHSU-974 cells subcutaneously and randomly divided into 2 groups: group A was fed a regular diet and group B a regular diet supplemented with 1% NM. Four weeks later, the mice were sacrificed and their tumors were excised, weighed and processed for histological analysis. NM inhibited the growth of OHSU-974 tumors by 47% and tumor burden by 50%. At lower concentrations, NM demonstrated no effect on proliferation, but at 1,000 μg/ml a 40% toxicity was observed. Zymography revealed the MMP-2 and PMA-induced MMP-9 secretion. NM suppressed the secretion of both MMPs in a dose-dependent manner, with a virtual inhibition at 500 μg/ml. NM inhibited OHSU-974 cell invasion through Matrigel in a dose-dependent manner with a complete block at 1,000 μg/ml. H&E staining showed no morphological changes below 500 μg/ml. These results suggest that NM has potential therapeutic use in the treatment of human FA HNSCC.

Expression of matrix metalloproteinase-12 is correlated with extracapsular spread of tumor from nodes with metastasis in head and neck squamous cell carcinoma

Matrix metalloproteinases (MMPs) play an important role in tumor invasiveness and metastasis. The aim of this study was to investigate the expression pattern of MMPs in the primary tumor of head and neck squamous cell carcinomas (HNSCC) with cervical node metastasis and to correlate the expression of MMP in the primary tumor with the presence of extracapsular spread (ECS) in nodes with metastasis. A retrospective study was conducted. Paraffin blocks were obtained from 40 HNSCC patients with cervical node metastasis who underwent surgery as an initial treatment between 2004 and 2011. Expressions of MMP-2, MMP-3, MMP-12, and MMP-14 were investigated immunohistochemically. MMP-2, MMP-3, MMP-12, and MMP-14 were expressed in 27, 47.5, 55, and 57.5 % of cases, respectively. MMP-12 expression was found to be significantly associated with ECS and correlated with nodal metastasis (p = 0.024, 0.011). No relation was found between MMP expression and survival. MMP-12 expressed in the primary tumor is a molecular marker that may be useful for predicting ECS in HNSCC patients with metastatic nodal disease.

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.

Imbalance of MMP-2 and MMP-9 expression versus TIMP-1 and TIMP-2 reflects increased invasiveness of human testicular germ cell tumours

The histological classification of testicular germ cell tumours (TGCTs) to seminoma or non-seminomatous germ cell tumours is at present the main criterion for the clinical outcome and selection of the treatment strategy. In view of the need to identify novel prognostic biomarkers for TGCTs, we investigated the expression of the matrix metalloproteinases MMP-2 and MMP-9 in testicular tumour tissues and cell lines of both seminoma and non-seminoma origin. Immunohistochemistry and zymography analysis of tumoural tissues showed significantly higher levels of MMP-2 and MMP-9 compared with normal testis with the active forms detected only in the tumour tissues. Three cell lines representative of the different tumour types, JKT-1 seminoma, NCCIT teratocarcinoma and NTERA2/D1 embryonal carcinoma were also evaluated for their expression of these MMPs using qPCR and zymography and for their invasive properties. The more invasive non-seminomatous teratocarcinoma and embryonal cells expressed considerably more MMP-2 and MMP-9 compared with seminoma cells exhibiting lower invasiveness. Furthermore, an inverse relation was observed between invasiveness and the expression of endogenous inhibitors TIMP-1 and TIMP-2. The MMP inhibitor Marimastat inhibited invasion in all cell lines, the highest inhibition was observed in the more invasive NTERA2/D1 and NCCIT cells, which presented the highest ratio of MMP-2 and MMP-9 vs. TIMP-1 and TIMP-2. These results highlight the importance of MMP-2 and MMP-9 in the invasiveness of testicular tumours and suggest that their levels, vs. those of TIMP-1 and TIMP-2, may represent potential biomarkers for testicular malignancy.

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.

Dioscorea nipponica Makino inhibits migration and invasion of human oral cancer HSC-3 cells by transcriptional inhibition of matrix metalloproteinase-2 through modulation of CREB and AP-1 activity

Oral cancer mortality has increased during the last decade due to the difficulties in treating related metastasis. Dioscorea nipponica Makino, a popular folk medicine, exerts anti-obesity and anti-inflammation properties. However, the effect of this folk medicine on metastasis of oral cancer has yet to be fully elucidated. The present study demonstrates that D. nipponica extracts (DNE), at a range of concentrations (0-50 μg/mL), concentration-dependently inhibited migration/invasion capacities of human oral cancer cells, HSC-3, without cytotoxic effects. The anti-migration effect of DNE was also observed in two other OSCC cell lines, Ca9-22 and Cal-27. Zymography, real time PCR, and Western blotting analyses revealed that DNE inhibited matrix metalloproteinase-2 (MMP-2) enzyme activity, and RNA and protein expression. The inhibitory effects of DNE on MMP-2 proceeded by up-regulating tissue inhibitor of metalloproteinase-2 (TIMP-2), as well as suppressing nuclear translocation and DNA binding activity of cAMP response element-binding (CREB) and activating protein-1 (AP-1) on the MMP-2 promoter in HSC-3 cells. In conclusion, DNE inhibited the invasion of oral cancer cells and may have potential use as a chemopreventive agent against oral cancer metastasis.

Clinical significance of molecular alterations in histologically negative surgical margins of head and neck cancer patients

The development of locoregional recurrence is the main reason for treatment failure in head and neck squamous cell carcinomas (HNSCC) and the remaining of tumor cells in surgical margins is associated with recurrence. Surgical margins are considered negative based on histologic assessment of the pathological specimen. However, this method lacks sensitivity in identifying cells that already started malignant transformation but have not yet developed a pathologic phenotype. We investigated the usefulness of assessing the expression of PTHLH, EPCAM, MMP9, LGALS1 and MET for the detection of molecular alterations in histologically negative surgical margins and determine the correlation of these tumor-related alterations with clinical and prognostic parameters. Differential gene expression was determined by quantitative RT-PCR analyses in normal mucosa, HNSCC and negative margin samples. Thirty-eight percent of the histologically negative surgical margins examined were margin-positive for overexpression of at least one of the genes evaluated. Moreover, MMP9 and PTHLH overexpression in the surgical margins was associated with the development of second primary tumors (p=0.002) and lower rates of local control (log rank test p=0.022; HR=4.186; p=0.035), respectively. These findings demonstrate that the overexpression of tumor-related genes in histologically negative surgical margins is a frequent event. The use of qRT-PCR may be an useful tool in detecting actually negative HNSCC surgical margins and the overexpression of specific genes in these margins could be helpful in the identification of patients with a higher risk of developing second primary tumors and local recurrences, thus aiding the surgeon in the delineation of the HNSCC resection extent and helping in the planning of adjuvant therapy.

Prognostic significance of matrix metalloproteinase-2, -8, -9, and -13 in oral tongue cancer

BACKGROUND

Oral tongue squamous cell carcinoma (OTSCC) often metastasizes to cervical lymph nodes. Mechanisms of this disease progression are not fully known. We aimed at finding new predictive markers for diagnosis and disease monitoring.

METHODS

Seventy-three consecutive T1N0M0 and T2N0M0 OTSCC patients treated at Helsinki University Central Hospital, Helsinki, Finland, in 1992-2002 were included. Tissue array blocks were prepared from primary tumors and immunostained. Immunoexpression of matrix metalloproteinase (MMP)-2, -8, -9, and -13 was compared with patient characteristics and outcome.

RESULTS

Nuclear expression of MMP-13, but not cytoplasmic expression of MMP-2, -8, and -9, was associated with invasion depth (P = 0.017) and tumor size (P = 0.008). Furthermore, high nuclear MMP-13 expression was predictive of poor outcome (P = 0.042).

CONCLUSION

Our results suggest that especially MMP-13 may be regarded as a prognostic biomarker in OTSCC.

Post-translational modifications of the extracellular matrix are key events in cancer progression: opportunities for biochemical marker development

The aim of this review is to discuss the potential usefulness of a novel class of biochemical markers, designated neoepitopes. Neoepitopes are post-translational modifications (PTMs) of proteins and are derived by processes, such as protease cleavage, citrullination, nitrosylation, glycosylation and isomerization. Each PTM results from a specific local physiological or pathobiological process. Identification of each modification to a tissue-specific protein may reveal a unique disease-specific biochemical marker. During cancer metastasis, the host tissue is extensively degraded and replaced by cancer-associated extracellular matrix (ECM) proteins. Furthermore, severe cellular stress and inflammation, caused by cancer, results in generation of PTMs, which will be distributed throughout the ECM. This gives rise to release of protein-specific fragments to the circulation. Here we highlight the importance of remodeling of the ECM in cancer and the generation of PTMs, which may be cancer specific and reflect disease progression; thus having potential for biochemical marker development.

Tumor Satellite in Predicting Occult Nodal Metastasis of Tongue Cancer

Objective. Tongue cancer is well known to have a high potential for locoregional metastasis. However, controversy about electively treating the neck in early-stage tongue cancer remains. Although many risk factors related to cervical occult nodal metastasis (ONM) have been investigated, the ability of the tumor to spread, a phenomenon that results from the intrinsic property of the tumor and its interaction with the surrounding environment, has seldom been addressed.

Study Design. Retrospective case series with chart review.

Setting. Tertiary referral hospital of university.

Subjects. Patients with early-stage squamous cell carcinoma of the oral tongue.

Results. In 71 eligible enrolled patients, ONM was detected in 19 (27%) patients, while the results were negative (ONM(−)) in 52 (73%) patients. The average tumor satellite distance (TSD) in the ONM(+) group was 4.1 ± 4.3 mm, in contrast to that in the ONM(−) group (1.0 ± 1.5 mm; P < .001). When stratified by increased TSD values, the significance of the difference between the 2 groups increased. For clinical applications, the optimal TSD threshold for determining the ONM probability was 3.5 mm. Multivariate analyses demonstrated that TSD was an independent prognosticator.

Conclusions. The results indicate that TSD is a feasible pathological parameter that is useful for determining the status of cervical nodal metastasis. It can be used as an indicator of potential cervical subclinical disease and as a guideline for deciding the necessity and modality of neck treatment.

Expression of matrix metalloproteinases and their inhibitors in squamous cell carcinoma of the tonsil and their clinical significance

OBJECTIVES

To investigate expressions of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in squamous cell carcinoma of the tonsil and to correlate expression profiles with clinicopathological characteristics.

METHODS

Paraffin blocks were obtained from 45 tonsil squamous cell carcinoma (SCC) patients, who underwent surgery as an initial treatment between 1994 and 2004, and from 20 normal controls. Expressions of MMP-2, MMP-9, MMP-13, TIMP-1, and TIMP-2 were investigated immunohistochemically.

RESULTS

The expressions of MMPs (except MMP-2) and TIMPs were found to be significantly different in tonsil SCC and normal control tissues. Furthermore, MMP-13 expression was found to be correlated with tumor invasion (P=0.05), and the expressions of MMP-9 and TIMP-1 with nodal metastasis (P=0.048, 0.031). No relation was found between MMP or TIMP expression and recurrence. However, MMP-9 expression was found to be significantly associated with 5-year survival in tonsil SCC patients by multivariate analysis (hazard ratio, 3.853; P=0.013).

CONCLUSION

Significant overexpressions of multiple MMPs and TIMPs were found in tonsil SCC tissues. Furthermore, our findings suggest that MMP-9 expression might be a useful prognostic factor.

Mast cells and matrix metalloproteinase 9 expression in actinic cheilitis and lip squamous cell carcinoma

OBJECTIVES

The aim of this study was to evaluate mast cell (MC) density and migration and their association with matrix metalloproteinase (MMP) 9 expression in squamous cell carcinoma (SCC) and actinic cheilitis (AC).

STUDY DESIGN

Tryptase, c-Kit, and MMP-9 expression was evaluated in 20 cases of SCC, 20 cases of AC, and 7 cases of normal lip (control samples) by immunohistochemistry techniques.

RESULTS

Tryptase(+) and c-Kit(+) MC densities were significantly higher in SCCs than in ACs and control samples (P < .001). However, no significant difference was found when comparing tryptase(+) and c-Kit(+) MC densities between ACs and control samples (P values .185 and .516, respectively). MMP-9 was strongly expressed in SCCs and moderately expressed in ACs and control samples. A highly significant association was found between tryptase(+) MC density and the expression of MMP-9 (P < .001).

CONCLUSIONS

The increase in MC density associated with the strong expression of MMP-9 may favor SCC progression.

Single nucleotide polymorphisms and haplotypes of MMP-14 are associated with the risk and pathological development of oral cancer

BACKGROUND

Matrix metalloproteinase (MMP)-14 is one of the pericellular collagenases to degrade extracellular matrix (ECM), which is involved to the modulation of susceptibility or clinicopathological features of a cancer. The contributions of MMP-14 on the susceptibility or clinicopathological features of certain cancers have been well documented, and the expression of MMP-14 in oral squamous cell carcinoma (OSCC) also has been observed. This study was designed to examine the association of MMP-14 gene polymorphisms with the susceptibility and clinicopathological development of OSCC.

METHODS

A total of 363 patients with OSCC and 506 healthy control subjects were recruited. Six single nucleotide polymorphisms (SNPs) of MMP-14 genes were analyzed by polymerase chain reaction-restriction fragment length polymorphism genotyping and haplotype-base analysis.

RESULTS

MMP-14 +7096 TC/CC genotypes might lower the risk of OSCC, and MMP-14 +6767 GA/AA genotypes cause a poor clinical status in OSCC patients. The +6727 C: +6767 G: +7096 T: +8153 G haplotype and diplotype increased the risk for OSCC by 1.706-fold (95% confidence interval (CI) 1.383-2.105) and 2.276-fold (95% CI = 1.531-3.384), respectively, compared with the reference. The diplotype with at least one CGTG exhibited a high risk (adjusted odds ratio, 1.639; 95% CI, 1.005-2.673) for developing a poor clinicopathological diagnosis of OSCC compared with the others/other diplotype.

CONCLUSIONS

The +7096 and +6767 polymorphic genotypes and haplotype +6727 C: +6767 G: +7096 T: +8153 G of MMP-14 gene might contribute to the prediction of susceptibility and pathological development of OSCC.

Overexpression of Eg5 predicts unfavorable prognosis in non-muscle invasive bladder urothelial carcinoma

OBJECTIVE

To investigate the relationship between Eg5 expression and prognosis of patients with non-muscle invasive bladder urothelial carcinoma.

METHODS

Eg5 expression was examined by immunohistochemistry in non-muscle invasive urothelial carcinoma specimens (grade: G1, 32 cases; G2, 92 cases; and G3, 39 cases. Stage: pTa, 49 cases and pT1, 114 cases). The correlation between clinicopathological characteristics and Eg5 expression was evaluated. The prognostic significance of Eg5 immunoreactivity was analyzed through survival analysis in 163 non-muscle invasive cases that were treated with transurethral resection and adjuvant intravesical instillations.

RESULTS

The expression of Eg5 was significantly associated with tumor grade (P = 0.006), with a trend towards significant association with stage (P = 0.057). The 163 patients with non-muscle invasive tumors were regularly followed with the mean of 32.52 (from 6 to 72) months. Univariate analysis showed Eg5 overexpression exhibited a significant unfavorable influence on intravesical recurrence (P = 0.012) while having only a marginal correlation with disease progression (P = 0.070). Subsequent Cox hazard multivariate analysis showed that both grade (P = 0.045) and Eg5 expression (P = 0.029) were independent predictors for early intravesical recurrence.

CONCLUSIONS

Overexpression of Eg5 correlates with poor differentiation of bladder cancer, and it represents an independent prognostic factor in predicting early intravesical recurrence in non-muscle invasive bladder carcinoma patients.

Immunohistochemical expression of matrix metalloproteinases in squamous cell carcinoma of the tongue and lower lip

OBJECTIVE

To evaluate the immunohistochemical expression of MMP-1, -2, -7, -9 and -26 in oral squamous cell carcinomas (SCCs) according to tumour site and histological grade of malignancy.

STUDY DESIGN

Fifteen cases of SCC of the lower lip and 15 cases of tongue SCC were selected and divided into low grade malignancy (n = 17) and high grade malignancy (n = 13).

RESULTS

Higher immunohistochemical expression of MMPs by neoplastic cells was observed in tongue SCCs, with a statistically significant difference for MMP-9 (P < 0.05). High-grade SCCs showed a higher expression of MMPs, except for MMP-2, with a statistically significant difference for MMP-7 (P < 0.05) and MMP-26 (P < 0.05). In addition, a direct association was observed between morphological scores of malignancy and MMP immunoreactivity, with the association being significant for MMP-7 and MMP-26.

CONCLUSION

The present results demonstrate the important role of MMPs in the development of SCCs of the lower lip and tongue.

Gene Expression Signatures of Lymph Node Metastasis in Oral Cancer: Molecular Characteristics and Clinical Significances

Even though lymph node metastasis accounts for the vast majority of cancer death in patients with oral cancer (OC), the molecular mechanisms of lymph node metastasis remain elusive. Genome-wide microarray analyses and functional studies in vitro and in vivo, along with detailed clinical observations, have identified a number of molecules that may contribute to lymph node metastasis. These include lymphangionenic cytokines, cell adhesion molecules, basement membrane-interacting molecules, matrix enzymes and relevant downstream signaling pathways. However, defined gene signatures from different studies are highly variable, which hinders their translation to clinically relevant applications. To date, none of the identified signatures or molecular biomarkers has been successfully implemented as a diagnostic or prognostic tool applicable to routine clinical practice. In this review, we will first introduce the significance of lymph node metastasis in OC, and clinical/experimental evidences that support the underlying molecular mechanisms. We will then provide a comprehensive review and integrative analysis of the existing gene expression studies that aim to identify the metastasis-related signatures in OC. Finally, the remaining challenges will be discussed and our insights on future directions will be provided.

Clinicopathological significance of E-cadherin, VEGF, and MMPs in gastric cancer

E-cadherin, vascular endothelial growth factor (VEGF), and matrix metalloproteinases (MMPs) are important molecules involved in tumor metastasis. In this study, we examined the expressions of E-cadherin, VEGF, MMP-1, MMP-2, and microvessel density (MVD), as well as microlymphatic vessel density (MLVD) in 200 cases of gastric cancer tissues, and determined the relationship between these parameters and the clinicopathological features and patient survival. Protein expressions, MVD, and MLVD were detected by immunohistochemistry. The correlation between the expression levels of these molecules and the clinicopathological features was analyzed. Patient survival was estimated by Kaplan and Meier analysis. Compared to normal gastric mucosa, expression of E-cadherin was reduced in 78% of gastric cancer tissues and 44.6% of adjacent non-cancerous gastric tissues. VEGF was positive in 81.5% of gastric cancer tissues, 35.7% of adjacent non-cancerous gastric tissues, and 10% of normal gastric mucosa. MMP-1 was positive in 80.5% of gastric cancer tissues, 69.6% of adjacent non-cancerous gastric tissues, and 20% of normal gastric mucosa. Reduced expression of E-cadherin was closely correlated with poor tumor differentiation and a deeper tumor invasion. Increased expressions of VEGF and MMP-1 were closely linked with poor differentiation and Lauren classification. Increased expression of MMP-2 was closely correlated with more lymph node metastasis, a deeper invasion, and a larger tumor size. More MVD was observed in VEGF-positive tissues than in VEGF negative tissues. Therefore, abnormal expressions of E-cadherin, VEGF, MMP-1, and MMP-2 are widely present in gastric cancer tissues. Abnormal expressions of E-cadherin, VEGF, and MMP-2 may represent the early molecular changes in the development of gastric cancer. Positive expression of E-cadherin and negative expression of VEGF and MMP-2 are correlated with a better patient survival.

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.

Expression profiles and clinical correlations of degradome components in the tumor microenvironment of head and neck squamous cell carcinoma

PURPOSE

Head and neck squamous cell carcinomas (HNSCC) are characterized by high morbidity and mortality, largely due to the high invasive and metastatic potential of these tumors, high recurrence rates, and low treatment responses. Proteinases have been implicated in several aspects of tumor growth and metastasis in a broad range of tumors including HNSCC.

EXPERIMENTAL DESIGN

Comprehensive expression profiling of proteinases [matrix metalloproteinases (MMPs), A disintegrin and metalloproteinase (ADAMs), and ADAMs with thrombospondin motif (ADAMTSs)] and their inhibitors [tissue inhibitor of metalloproteinases (TIMPs)] was done using quantitative real-time reverse transcription-PCR analysis of a large cohort of tissue samples representing the tumor (n = 83), the invasive margin (n = 41), and the adjacent tissue (n = 41) from 83 HNSCC patients, along with normal tissue controls (n = 13), as well as cell lines established from tumors of 34 HNSCC patients.

RESULTS

The results show specifically elevated gene expression of several proteinases, including MMP1, MMP3, MMP10, and MMP13 within tumor tissue and peritumoral adjacent tissue. In addition, the results identify several novel HNSCC-associated proteinases, including ADAM8, ADAM9, ADAM17, ADAM28, ADAMTS1, ADAMTS8, and ADAMTS15. There were also significant differences in proteinase expression based on clinical parameters, i.e., tumor location, grade, and local invasion. MMP13 expression was significantly higher in large (>4 cm) locally invasive tumors (P < 0.05). MMP9 expression was significantly decreased in tumors with regional metastasis, whereas increased expression of ADAM8 was noted in the metastatic tumors (P < 0.001 for both).

CONCLUSIONS

These findings suggest the HNSCC degradome as a valuable source of diagnostic, predictive, and prognostic molecular markers for these malignant tumors.

Therapeutic effect of topical 5-fluorouracil in conjunctival squamous carcinoma is associated with changes in matrix metalloproteinases and tissue inhibitor of metalloproteinases expression

PURPOSE

To evaluate matrix metalloproteinases (MMP)-2, MMP-9, and tissue inhibitor of metalloproteinase (TIMP)-1 expression in a case of conjunctival intraepithelial squamous cell carcinoma (SCC) treated with topical 5-fluorouracil (5-FU) chemotherapy.

METHODS

Clinicopathologic case report.

RESULTS

A 71-year-old male patient presented with an intraepithelial conjunctival SCC. Because of a recurrence, he was placed on topical 5-FU for 4 weeks that ultimately led to a complete resolution of the disease. Conjunctival biopsies, impression cytologies, and tear samples were taken from the mass and the contralateral healthy eye. An overexpression of MMP-2, MMP-9, and TIMP-1 was observed in the tumor by immunohistochemistry. Clinical resolution of the neoplasm obtained using topical 5-FU was accompanied by a reduction in the expression of MMP-2, MMP-9, and TIMP-1 in tears and dysplastic conjunctival epithelium.

CONCLUSIONS

In our case report, we have shown that gelatinase and TIMP-1 are unregulated in conjunctival SCC and can be monitored as a marker of response to topical chemotherapy. Further studies are required to define the role of MMPs in growth and resolution of ocular tumors.

Marked Inhibition of Growth and Invasive Parameters of Head and Neck Squamous Carcinoma FaDu by a Nutrient Mixture

Head and neck squamous cell carcinomas (HNSCCs) are known for their aggressive growth and propensity to metastasize. The authors investigated the effect of a novel nutrient mixture (NM) containing ascorbic acid, lysine, proline, and green tea extract on human HNSCC cell line FaDu in vivo and in vitro. Athymic male nude mice (n = 12) were inoculated with 3 × 106 FaDu cells subcutaneously and randomly divided into 2 groups: group A was fed a regular diet and group B a regular diet supplemented with 0.5% NM. Four weeks later, the mice were sacrificed and their tumors were excised, weighted, and processed for histology. In vitro, FaDu cells were cultured in Dulbecco's modified Eagle's medium and exposed to NM at 0 to 1000 µg/mL in triplicate. Cell proliferation was assessed by MTT assay, matrix metalloproteinase (MMP) secretion by gelatinase zymography, invasion through Matrigel, apoptosis by live-green caspases, and cell morphology by hematoxylin—eosin staining. NM inhibited the growth of tumors by 55% ( P = .0002) and exhibited dose-dependent toxicity on FaDu cells in vitro, with 53% ( P = .0003) at 1000 µg/mL NM. Zymography revealed MMP-2 and phorbol 12-myristate 13-acetate—induced MMP-9 secretion. NM inhibited secretion of both MMPs in a dose-dependent manner, with virtual total inhibition at 1000 µg/mL. NM significantly inhibited FaDu invasion through Matrigel with total block at 1000 µg/mL. NM induced dose-dependent apoptosis. In conclusion, NM has therapeutic potential in the treatment of HNSCC by significantly suppressing tumor growth and significantly inhibiting MMP secretion and invasion of HNSCC cells in vitro.

Reproducibility of immunostaining quantification and description of a new digital image processing procedure for quantitative evaluation of immunohistochemistry in pathology

Quantification of immunostaining is a widely used technique in pathology. Nonetheless, techniques that rely on human vision are prone to inter- and intraobserver variability, and they are tedious and time consuming. Digital image analysis (DIA), now available in a variety of platforms, improves quantification performance: however, the stability of these different DIA systems is largely unknown. Here, we describe a method to measure the reproducibility of DIA systems. In addition, we describe a new image-processing strategy for quantitative evaluation of immunostained tissue sections using DAB/hematoxylin-stained slides. This approach is based on image subtraction, using a blue low pass filter in the optical train, followed by digital contrast and brightness enhancement. Results showed that our DIA system yields stable counts, and that this method can be used to evaluate the performance of DIA systems. The new image-processing approach creates an image that aids both human visual observation and DIA systems in assessing immunostained slides, delivers a quantitative performance similar to that of bright field imaging, gives thresholds with smaller ranges, and allows the segmentation of strongly immunostained areas, all resulting in a higher probability of representing specific staining. We believe that our approach offers important advantages to immunostaining quantification in pathology.