MMP-2 but not MMP-9 associated with COX-2 and survival in gastric cancer

Multi-Targeting Anticancer Activity of a New 4-Thiazolidinone Derivative with Anti-HER2 Antibodies in Human AGS Gastric Cancer Cells

Combining chemotherapy with immunotherapy still remains a regimen in anticancer therapy. Novel 4-thiazolidinone-bearing hybrid molecules possess well-documented anticancer activity, and together with anti-HER2 antibodies, may represent a promising strategy in treating patients with gastric cancer with confirmed human epidermal growth factor receptor 2 (HER2) expression. The aim of the study was to synthesize a new 4-thiazolidinone derivative (Les-4367) and investigate its molecular mechanism of action in combination with trastuzumab or pertuzumab in human AGS gastric cancer cells. AGS cell viability and antiproliferative potential were examined. The effect of the tested combinations as well as monotherapy on apoptosis and autophagy was also determined. Metalloproteinase-2 (MMP-2), intercellular adhesion molecule 1 (ICAM-1), pro-inflammatory and anti-inflammatory cytokine concentrations were also demonstrated by the ELISA technique. We proved that pertuzumab and trastuzumab were very effective in increasing the sensitivity of AGS gastric cancer cells to novel Les-4367. The molecular mechanism of action of the tested combination is connected with the induction of apoptosis. Additionally, the anticancer activity is not associated with the autophagy process. Decreased concentrations of pro-inflammatory cytokines, MMP-2 and ICAM-1-were observed. The novel combination of drugs based on anti-HER2 antibodies with Les-4367 is a promising strategy against AGS gastric cancer cells.

Combined COX-2/PPARγ Expression as Independent Negative Prognosticator for Vulvar Cancer Patients

Vulvar cancer incidence numbers have been rising steadily over the past decades. Especially the number of young patients with vulvar cancer increased recently. Therefore, the need to identify new prognostic factors for vulvar carcinoma is more apparent. Cyclooxygenase-2 (COX-2) has long been an object of scientific interest in the context of carcinogenesis. This enzyme is involved in prostaglandin synthesis and the latter binds to nuclear receptors like PPARγ. Therefore, the aim of this study was to investigate COX-2- and PPARγ- expression in tissues of vulvar carcinomas and to analyze their relevance as prognostic factors. The cytoplasmatic expression of COX-2 as well as PPARγ is associated with a significantly reduced survival, whereas nuclear expression of PPARγ results in a better survival. Especially the combined expression of both COX-2 and PPARγ in the cytoplasm is an independent negative prognosticator for vulvar cancer patients.

Study of the Relationship between MMP-2 and MMP-9 and Her2/neu Overexpression in Gastric Cancer: Clinico- Pathological Correlations

Background:

The relationship between the expressions of matrix metalloproteinases with clinico-pathological data on gastric cancer has been investigated in many countries, but this relationship remains unexplored in Iranian patients. Also, the correlation of the MMPs and the HER-2/neu proto-oncogene with other clinic-pathological variables has been evaluated for several other malignancies, but little effort has been made to shed light on the relationship with gastric cancer.

Methods:

We investigated MMP-2 and MMP-9 expression and HERE-2/neu overexpression in 48 gastric cancer patients referred to Afzalipour Hospital, associated with Kerman Medical University. Immunohistochemistry staining with rabbit polyclonal antibodies was used. Data statistical analysis was done by SPSS software (Version 20.0).

Results:

The mean age was 59, most of the patients were male (79.2%), and the average tumor size was larger than 5 centimeters in its greatest diameter. The majority of tumors were of the intestinal subtype and were located in the pyloric and antrum regions (43.8%). Invasion to muscularis properia was seen in 87.5% of the tumors (T3). MMP-2 and MMP-9 were highly expressed in 58.3% and 50% of cases, respectively, and Her-2/neu positivity was 10.4%. MMP-2, MMP-9 and HER-2 were found to have no relation with any clinicopathological parameters.

Conclusion:

According to the results of this study, MMP-2 and MMP-9 were highly expressed in gastric cancer, but there was no significant association with other clinicopathological variables.

Assessment of the correlation between oxidative stress and expression of MMP-2, TIMP-1 and COX-2 in human aortic smooth muscle cells

INTRODUCTION

Smooth muscle cells (SMCs) are considered to be the main producer of matrix metalloproteinase-2 (MMP-2) participating primarily in extracellular matrix (ECM) remodeling. Any disturbances in ECM structure may underlie the pathogenesis of many cardiovascular diseases and contribute to angiogenesis, cancer development, invasion or metastasis. The purpose of the study was to examine the effect of oxidative stress on the expression of MMP-2, its tissue inhibitor type 1 (TIMP-1) and cyclooxygenase-2 (COX-2) in human aortic smooth muscle cells (HASMCs).

MATERIAL AND METHODS

HASMCs were treated with exogenously applied H₂O₂ or TNF-α. N-acetylcysteine (NAC) was used as an antioxidant. Gene expression levels were measured by real-time PCR and the protein levels were determined using ELISA assay.

RESULTS

The studies revealed no association between oxidative stress and either mRNA quantity or protein secretion of MMP-2 and TIMP-1. However, we found markedly reduced (p < 0.001) MMP-2 secretion in cells incubated with NAC. HASMCs stimulated with TNF-α demonstrated a significantly increased COX-2 mRNA level as well as enzyme activity. H₂O₂-induced cells showed lowered COX-2 activity in comparison to untreated cells. MMP-2 and TIMP-1 expression did not change after COX-2 inhibition with DuP-697.

CONCLUSIONS

We did not find any effect of oxidative stress on expression of MMP-2 and TIMP-1 in HASMCs. However, COX-2 mRNA and protein level were elevated in these conditions. There was no correlation between COX-2 activity and MMP-2 and TIMP-1 mRNA expression or protein secretion.

Targeting Lipid Peroxidation for Cancer Treatment

Cancer is one of the highest prevalent diseases in humans. The chances of surviving cancer and its prognosis are very dependent on the affected tissue, body location, and stage at which the disease is diagnosed. Researchers and pharmaceutical companies worldwide are pursuing many attempts to look for compounds to treat this malignancy. Most of the current strategies to fight cancer implicate the use of compounds acting on DNA damage checkpoints, non-receptor tyrosine kinases activities, regulators of the hedgehog signaling pathways, and metabolic adaptations placed in cancer. In the last decade, the finding of a lipid peroxidation increase linked to 15-lipoxygenases isoform 1 (15-LOX-1) activity stimulation has been found in specific successful treatments against cancer. This discovery contrasts with the production of other lipid oxidation signatures generated by stimulation of other lipoxygenases such as 5-LOX and 12-LOX, and cyclooxygenase (COX-2) activities, which have been suggested as cancer biomarkers and which inhibitors present anti-tumoral and antiproliferative activities. These findings support the previously proposed role of lipid hydroperoxides and their metabolites as cancer cell mediators. Depletion or promotion of lipid peroxidation is generally related to a specific production source associated with a cancer stage or tissue in which cancer originates. This review highlights the potential therapeutical use of chemical derivatives to stimulate or block specific cellular routes to generate lipid hydroperoxides to treat this disease.

High Expression of MMP-9 in Primary Tumors and High Preoperative MPO in Serum Predict Improved Prognosis in Colorectal Cancer with Operable Liver Metastases

INTRODUCTION

The liver metastases of colorectal cancer (CRC) can be surgically treated in selected cases, with continuously improving results. Matrix metalloproteinases (MMPs) contribute to cancer invasion by degrading the extracellular matrix, and elevated levels of MMP-2, MMP-8, and MMP-9 have been detected in several malignancies. Myeloperoxidase (MPO) is a mediator of tissue damage that can oxidatively activate latent MMPs. We evaluated the prognostic value of MMP-2, MMP-8, and MMP-9 in tissue samples of primary tumors and liver metastases and the pre- and postoperative serum levels of MMP-8, MMP-9, and MPO in CRC patients undergoing liver resection.

METHODS

Tissue and serum samples were obtained from 111 patients who had primary colorectal tumors and their liver metastases surgically treated at the Helsinki University Hospital between 1988 and 2007. Tissue expression of MMP-2, MMP-8, and MMP-9 in primary tumors and liver metastases was evaluated by immunohistochemistry. Pre- and postoperative serum concentrations of MMP-8, MMP-9, and MPO were determined using a time-resolved immunofluorometric assay or commercially available enzyme-linked immunosorbent assay kits. Clinical data were retrieved from patient records and the Central Statistical Office of Finland. Associations with disease-free survival (DFS) and overall survival (OS) were estimated using Cox regression analysis and the Kaplan-Meier method.

RESULTS

High expression of MMP-9 in colorectal tumor tissue was associated with better DFS (p = 0.010), and high preoperative MPO in serum with improved DFS and OS (p < 0.001 and p = 0.014, respectively). The prognostic significance varied according to gender, age, and the synchronicity of liver metastases.

CONCLUSION

Low preoperative MPO in serum might identify patients at high risk of recurrence and death after resection of colorectal liver metastases. Elevated preoperative MPO and high expression of MMP-9 in colorectal tumor tissue indicate an improved prognosis. The use of these biomarkers should be adjusted according to clinical characteristics.

Role of extra cellular proteins in gastric cancer progression and metastasis: an update

Background

Gastric cancer (GC) is one of the most common cancers in the world with a high ratio of mortality. Regarding the late diagnosis, there is a high ratio of distant metastasis among GC cases. Despite the recent progresses in therapeutic modalities, there is not still an efficient therapeutic method to increase survival rate of metastatic GC cases.

Main body

Apart from the various intracellular signaling pathways which are involved in tumor cell migration and metastasis, the local microenvironment is also a critical regulator of tumor cell migration. Indeed, the intracellular signaling pathways also exert their final metastatic roles through regulation of extra cellular matrix (ECM). Therefore, it is required to assess the role of extra cellular components in biology of GC.

Conclusion

In the present review, we summarize 48 of the significant ECM components including 17 ECM modifying enzymes, seven extracellular angiogenic factors, 13 cell adhesion and cytoskeletal organizers, seven matricellular proteins and growth factors, and four proteoglycans and extra cellular glycoproteins. This review paves the way of determination of a specific extra cellular diagnostic and prognostic panel marker for the GC patients.

P4HA3 is Epigenetically Activated by Slug in Gastric Cancer and its Deregulation is Associated With Enhanced Metastasis and Poor Survival

Prolyl 4-hydroxylase alpha subunit is the enzymic active site of prolyl 4-hydroxylase, which is a critical enzyme to maintain the stability of newly synthesized collagens. The expression profile and functional role of P4HA3 in gastric cancer have not been explored. In the Cancer Genome Atlas-Stomach Cancer, P4HA3 RNA is significantly upregulated in gastric cancer than in normal stomach tissues. In the Human Protein Atlas, Prolyl 4-hydroxylase alpha subunit is not detectable by immunohistochemistry staining in normal stomach tissues, but it has weak staining in 7 of 12 gastric cancer tissues. Further study showed that SNAI2 (encoding Slug) is highly coexpressed with P4HA3 (Pearson r = 0.70) in Cancer Genome Atlas-Stomach Cancer. In vitro cell assay showed that Slug could efficiently bind to the P4HA3 promoter and increase its transcription. P4HA3 exon array data in Cancer Genome Atlas-Stomach Cancer revealed that 2 exons are significantly upregulated in M1 (N = 27) cases than in M0 (N = 367) cases. In MKN-45 and AGS cells, P4HA3 upregulation could enhance cell motility and invasiveness. In Cancer Genome Atlas-Stomach Cancer, high P4HA3 exon expression is associated with significantly worse 5-year and 10-year overall survival (P = .007 and .009, respectively). Data mining in Kaplan-Meier plotter also showed that high P4HA3 expression is related to unfavorable overall survival (hazard ratio: 1.54, 95% confidence interval: 1.23-1.93, P < .001) and first progression-free survival (hazard ratio: 1.64, 95% confidence interval: 1.29-2.1, P < .001). Based on findings above, we infer that P4HA3 is epigenetically activated by Slug, and its deregulation is associated with enhanced metastasis and poor survival of gastric cancer.

Integrin αvβ6 and matrix metalloproteinase 9 correlate with survival in gastric cancer

AIM: To investigate the expression of integrin αvβ6 and matrix metalloproteinase 9 (MMP-9), their association with prognostic factors and to assess their predictive role in gastric cancer patients.

METHODS: Immunohistochemistry was used to determine the expressions of integrin αvβ6 and MMP-9 in 126 specimens from patients with primary gastric carcinoma. Associations between immunohistochemical staining and various clinic pathologic variables of tissue specimens were evaluated by the χ² test and Fisher’s exact test. Expression correlation of αvβ6 and MMP-9 was assessed using bivariate correlation analysis. The patients were followed-up every 3 mo in the first two years and at least every 6 mo afterwards, with a median follow-up of 56 mo (ranging from 2 mo to 94 mo). Four different combinations of αvβ6 and MMP-9 levels (that is, both markers positive, both markers negative, αvβ6 positive with MMP-9 negative, and αvβ6 negative with MMP-9 positive) were evaluated for their relative effect on survival. The difference in survival curves was evaluated with a log-rank test. Survival analysis was conducted using the Kaplan-Meier survival and Cox proportional hazards model analysis.

RESULTS: The expressions of integrin αvβ6 and MMP-9 were investigated in 126 cases, among which 34.92% were positive for αvβ6 expression, and 42.06% for MMP-9 expression. The expression of αvβ6 was associated with Lauren type, differentiation, N stage, and TNM stage (the P values were 0.006, 0.038, 0.016, and 0.002, respectively). While MMP-9 expression was associated with differentiation, T stage, N stage, and TNM stage (the P values were 0.039, 0.014, 0.033, and 0.008, respectively). The positive correlation between αvβ6 and MMP-9 in gastric cancer was confirmed by a correlation analysis. The Kaplan-Meier survival analysis showed that patients with expression of αvβ6 or MMP-9 alone died earlier than those with negative expression and that patients who were both αvβ6 and MMP-9 positive had a shorter overall survival than those with the opposite pattern (both αvβ6 and MMP-9 negative) (P = 0.000). A Cox model indicated that positive expression of αvβ6 and MMP-9, diffuse Lauren type, as well as a senior grade of N stage, M stage, and TNM stage were predictors of a poor prognosis in univariate analysis. Only αvβ6 and MMP-9 retained their significance when adjustments were made for other known prognostic factors in multivariate analysis (RR = 2.632, P = 0.003 and RR = 1.813, P = 0.007).

CONCLUSION: The expression of αvβ6 and MMP-9 are closely correlated, and the combinational pattern of αvβ6 and MMP-9 can serve as a more effective prognostic index for gastric cancer patients.

Matrix metalloproteinase 2 (MMP-2) and their tissue inhibitor 2 (TIMP-2) in gastric cancer patients

BACKGROUND

Matrix metalloproteinase 2 (MMP-2) is able to degrade type IV collagen and its activity is mostly regulated by tissue inhibitor of matrix metalloproteinase 2 (TIMP-2). These proteins might play a role in tumor progression, including gastric cancer (GC).

METHODS

The study included 108 individuals, GC patients and healthy subjects. Serum levels of all analyzed markers were evaluated by the immunological methods, while immunohistochemistry was used to assess the expression of these proteins in GC, interstitial inflammatory cells and normal tissues.

RESULTS

The percentage of positive reactions of MMP-2 and TIMP-2 was higher in GC and inflammatory cells compared to normal tissue, while serum levels of these proteins were statistically lower in GC patients in comparison to healthy subjects. There was a significant positive correlation between TIMP-2 immunoreactivity in inflammatory cells and the presence of lymph node metastasis. Area under ROC curve (AUC) for TIMP-2 was higher than MMP-2, while serum MMP-2 was an independent prognostic factor of GC patients' survival.

CONCLUSION

Our findings suggest that TIMP-2 seems to be a predictor of tumor progression, especially for nodal involvement, whereas serum MMP-2 might be useful as an independent prognostic factor of patients' survival.

Expression patterns of stromal MMP-2 and tumoural MMP-2 and -9 are significant prognostic factors in invasive ductal carcinoma of the breast

Matrix metalloproteinases (MMPs) are matrix-degrading enzymes that play a pivotal role in aggressive behaviours, such as rapid tumour growth, invasion, and metastasis, of several types of solid tumours. In particular, stromal MMP-2 plays important roles in the progression of malignant tumours, but most clinical studies have focused on tumoural MMP-2 and -9 expression, and not stromal MMP-2 expression. One hundred and seventy-seven cases diagnosed as invasive ductal carcinoma of the breast between 2000 and 2005 were included in this study. Expressions of tumoural MMP-2 and -9 and stromal MMP-2 were analysed by immunostaining on a tissue microarray. Subsequently, the associations between those results and various clinicopathological parameters were evaluated. Stromal MMP-2 expression correlated significantly with clinicopathological parameters such as advanced T category, larger tumour size, high histological grade, tumour necrosis, ER- and PR-negative, and HER-2-positive (all p < 0.05). In univariate and multivariate analyses, overall survival was linked with stromal MMP-2 expression as well as dual expression of stromal MMP-2 and tumoural MMP-2 and -9 (all p < 0.05). Stromal MMP-2 expression may play a crucial role in predicting aggressive clinical behaviour in breast cancer patients.

Immunoexpression of metalloproteinases 2 and 14 and TIMP-2 inhibitor in main types of primary gastric carcinomas and lymph node metastasis

Metalloproteinase-2 (MMP-2) and -14 (MMP-14) and the tissue inhibitor of metalloproteinases type 2 (TIMP-2) participate in epithelial-mesenchymal transition and tumor progression in many cancers. However, the correlation between these enzymes in gastric cancer and the metastatic potential to their respective lymph node needs to be determined. Here, we evaluated the expression of these enzymes in gastric carcinoma and lymph node metastases and their possible involvement in tumor progression. Histological samples from 83 patients with gastric cancer and their respective lymph nodes were used. MMP-2, MMP-14 and TIMP-2 immunoexpression was scored. TIMP-2 expression in tumor-associated macrophages occurred more frequently than in normal mucosa (P = 0.0128). Female tumor samples presented higher MMP-2 expression (P = 0.0248), while TIMP-2 occurred mainly in patients over 50 years old (P = 0.0034). MMP-2 was higher expressed in primary tumor macrophages than in neoplastic cells (P = 0.0118), and was also seen in macrophages from metastatic-affected lymph nodes of intestinal and diffuse histotypes (P = 0.0006). MMP-2, MMP-14 and TIMP-2 expression in mononuclear cells might be correlated with progression of gastric cancer. MMP-14 production by macrophages appears to be more involved in diffuse gastric cancer progression.

Relationships between abnormal MMP2 expression and prognosis in gastric cancer: a meta-analysis of cohort studies

We carried out this current meta-analysis of relevant cohort studies in an attempt to investigate the relationships between abnormal matrix metalloproteinases-2 (MMP2) expression and gastric cancer (GC) prognosis. A range of electronic databases were searched for relevant articles without any language restrictions: Web of Science (1945-2013), the Cochrane Library Database (Issue 12, 2013), PubMed (1966-2013), EMBASE (1980-2013), CINAHL (1982-2013), and the Chinese Biomedical Database (CBM) (1982-2013). Meta-analysis was conducted using the STATA 12.0 software. Crude hazard ratios (HRs), with 95% confidence intervals (95% CIs), were calculated. Ten clinical cohort studies with a total of 1669 GC patients were included in this meta-analysis. The results of our meta-analysis suggested that MMP2-positive patients display a shorter overall survival (OS) than MMP2-negative patients (HR=1.31, 95% CI=0.98-1.63, p<0.001). Subgroup analysis based on ethnicity revealed that abnormal MMP2 expression was associated with significantly worse OS in patients with GC among both Caucasian and Asian populations (all p<0.05). Our meta-analysis indicated that abnormal MMP2 expression may be strongly correlated with poor prognosis in patients with GC. Thus, MMP2 expression may serve as an independent prognostic factor for GC.

The prognostic role of matrix metalloproteinase 2 in gastric cancer: a systematic review with meta-analysis

PURPOSE

The prognostic role of matrix metalloproteinase 2 (MMP-2) in gastric cancer remains controversial. We systematically reviewed the evidence for assessment of MMP-2 expression in gastric cancer to elucidate this issue.

METHOD

Pubmed, Embase and Web of Science were searched to identify eligible studies to evaluate the association of MMP-2 expression and overall survival and clinicopathological features of gastric cancer.

RESULTS

MMP-2 overexpression was significantly correlated with poor OS of gastric cancer patients (HR 1.92, 95 % CI 1.48-2.48). Subgroup analysis indicated that MMP-2 overexpression had an unfavorable impact on OS in Asian countries (HR 2.23, 95 % CI 1.57-3.17) and European countries (HR 1.43, 95 % CI 1.13-1.80). Furthermore, MMP-2 overexpression was significantly associated with TNM stage (TIII/TIV vs TI/TII: OR 2.17, 95 % CI 1.64-2.87), the depth of invasion (T3/T4 vs T1/T2: OR 2.59, 95 % CI 1.63-4.12), lymph node metastasis (positive vs negative: OR 2.21, 95 % CI 1.69-2.88), and distant metastasis (positive vs negative: OR 4.44, 95 % CI 1.24-15.94).

CONCLUSION

This meta-analysis indicated that MMP-2 overexpression might be a predictive factor for poor prognosis for gastric cancer.

Harmine induces apoptosis and inhibits tumor cell proliferation, migration and invasion through down-regulation of cyclooxygenase-2 expression in gastric cancer

Cyclooxygenase-2 (COX-2) plays an important role in the carcinogenesis and progression of gastric cancer. Harmine is reported as a promising drug candidate for cancer therapy; however, effects and action mechanism of harmine on the human gastric cancer cells remain unclear. This study evaluated the anti-tumor effects of harmine on human gastric cancer both in vitro and in vivo. The cell proliferation was determined using MTT colorimetric assay. Apoptosis was measured by DAPI staining and flow cytometry analysis. The wound healing and transwell invasion assays were performed to evaluate the effects of harmine on the migration and invasion of gastric cancer cells. The expression of COX-2, proliferating cell nuclear antigen (PCNA), Bcl-2, Bax and matrix metalloproteinase-2 (MMP-2) was detected by Western blot analysis. Our results showed that harmine significantly inhibited cellular proliferation, migration, invasion and induced apoptosis in vitro, as well as inhibited tumor growth in vivo. In addition, harmine significantly inhibited the expression of COX-2, PCNA, Bcl-2 and MMP-2 as well as increased Bax expression in gastric cancer cells. These results collectively indicate that harmine induces apoptosis and inhibits proliferation, migration and invasion of human gastric cancer cells, which may be mediated by down-regulation of COX-2 expression.

Expression of the matrix metalloproteases 2, 14, 24, and 25 and tissue inhibitor 3 as potential molecular markers in advanced human gastric cancer

Background. During progression of gastric cancer (GC), degradation of the extracellular matrix is mediated by the matrix metalloproteases (MMPs) and their tissue inhibitors (TIMPs): changes in the expression of these have been related to unfavorable prognosis in GC. Objective. To analyze the expression of certain MMPs and TIMPs in chronic superficial gastritis (SG) and GC. Methods. The expression of MMPs and TIMPs was determined using qRT-PCR; the expression was classified, using threshold cycle (C_T) values, as very high (C_T ≤ 25), high (C_T = 26–30), moderate (C_T = 31–35), low (C_T = 36–39), or not detected (C_T = 40). Strength of association was estimated between the proteins, which were detected by Western blot, and the risk of developing GC. Results. We found a high expression of MMP1, MMP2, MMP14, TIMP1, and TIMP3; moderate one of MMP9 and MMP25, and low one of MMP13 and MMP24 in both tissues. In absolute mRNA levels, significant differences were found in expression of MMP2, MMP24, and MMP25, which are overexpressed in GC compared with SG. The presence of the proteins MMP-14 and TIMP-3 was associated with the risk of developing GC. Conclusions. We consider that MMP2, MMP24, and MMP25 and the proteins MMP-14 and TIMP-3 could be candidates for prognostic molecular markers in GC.

Cyclooxygenase-2 expression is associated with poor overall survival of patients with gastric cancer: a meta-analysis

BACKGROUND

Cyclooxygenase-2 (COX-2) is believed to be involved in gastric carcinogenesis. However, it is still controversial whether COX-2 expression can be regarded as a prognostic factor for gastric cancer patients.

AIM

To obtain a more accurate relationship between COX-2 overexpression and prognosis in gastric cancer by meta-analysis.

METHOD

Relevant articles published up to May 2013 were searched by use of several keywords in electronic databases. Separate hazard ratio (HR) estimates and 95 % confidence intervals (95 % CI) for COX-2 overexpression and overall survival (OS) and disease-free survival (DFS) with gastric cancer were extracted. Combined HR with 95 % CI was calculated by use of Stata11.0 software to estimate the size of the effect. Publication bias testing and sensitivity analysis were also performed.

RESULTS

A total of 27 studies which included 3,891 gastric cancer patients were combined in the final analysis. Combined results suggested that COX-2 overexpression was associated with an unfavorable OS (HR 1.58, 95 % CI 1.36-1.84) but not DFS (HR 1.15, 95 % CI 0.93-1.43) among patients with gastric cancer. Publication bias was absent. Sensitivity analysis suggested that the results of this meta-analysis were robust.

CONCLUSIONS

The results of this meta-analysis suggest that high COX-2 expression may be an independent risk factor for poor OS of patients with gastric cancer. More large prospective studies are now needed to further clarify the prognostic value of COX-2 expression for DFS in gastric cancer.

MMP-2 and DcR3 expression in esophageal cancer tissue and correlation with patient survival

OBJECTIVE

This study aims to explore the expression of decoy receptor 3 (DcR3) and the matrix metalloproteinase-2 (MMP-2) in esophageal carcinoma and their relationship with patient survival.

METHODS

The EnVision(TM) immunohistochemistry method was used to examine DcR3 and MMP-2 expression in 150 surgical biopsies of esophageal carcinoma. Expression level was compared with clinical indices and with patient survival.

RESULTS

In cancer tissues, the positive expression rate of DcR3 and MMP-2 was 54.00% and 54.67% respectively; this was higher than levels in adjacent normal tissue. DcR3 and MMP-2 were positively correlated with carcinoma size, lymphatic metastasis, invasion degree, clinical stage and 3-year survival. DcR3 and MMP-2 were not correlated with gender, age and tumor degree of differentiation. DcR3 and MMP-2 were positively correlated between in the two groups (r = 0.37, P < 0.01). Kaplan-Meier survival curve showed that higher rates of DcR3 and MMP-2 expression correlated with lower survival.

CONCLUSIONS

Determining DcR3 and MMP-2 expression may be useful for the diagnosis, treatment and prognosis of patients with esophageal carcinoma.

Claudins and gastric carcinogenesis

Gastric carcinoma arises from aberrant growth of normal gastric mucosa. There is increasing evidence that claudins (CLDNs) may play a critical role in the significant steps of gastric tumorigenesis, from metaplasia to metastasis. The CLDN family which consists of at least 27 member proteins is known to mediate selective permeability in cellular tight junctions. It is now established that CLDNs are differentially altered in gastric cancer and CLDN proteins are believed to play different roles in the growth and progression of gastric cancer.

VEGF and metalloproteinase 2 (MMP 2) expression in gastric cancer tissue

BACKGROUND

Neoplasms are the second leading cause of death in Poland after vessel diseases, despite the huge progress in medical sciences in the last 20 years. Recently, gastric cancer morbidity has decreased, but mortality is still at a high level.

MATERIAL/METHODS

Tissues from 24 patients with a histopathologically diagnosed mucosal and adenomucosal gastric cancer were tested. Patients were divided into 2 equal groups: patients without metastases (G1) and patients with metastases in the liver (G2). In all tested tissues of G1 and G2, the expression of VEGF (vascular endothelial growth factor) and metalloproteinase 2, respectively, were estimated.

RESULTS

Results revealed a statistically significant increase in the VEGF expression for G1 and G2 in relation to the margin (p1<0.001; p2<0.001). The increase of gene expression for VEGF did not significantly differ statistically in G1 and G2. The obtained results revealed a statistically significant difference in the increase of gene expression for MMP-2 in G1 in relation to the margin (p<0.05) and a very high one in G2 in relation to the average margin value (p<0.001). A highly statistically significant correlation was obtained for VEGF and MMP-2 in the tissue of patients with metastases (p<0.001; r=0.714). The highly elevated expression of MMP-2 in the tissue of gastric cancer in patients with metastases confirms its participation in the invasiveness of the neoplasmatic process.

CONCLUSIONS

The highly significant correlation between VEGF and MMP-2 suggests a connection between both mechanisms in the progression of gastric cancer.

Quercetin reduces cell invasion and down-regulates matrix metallopeptidase 2 expression in human gastric cancer cell line BGC-823

AIM: To investigate the effect of quercetin on the migration of human gastric cancer BGC-823 cells and to explore possible mechanisms involved.

METHODS: After BGC-823 cells were treated with different doses of quercetin, the anchorage-independent growth of cells was evaluated by colony formation assay, cell invasion ability was determined by Boyden chamber assay, and the mRNA and protein expression of matrix metallopeptidase-2 (MMP-2) was detected by real-time RT-PCR and Western blot, respectively.

RESULTS: Quercetin reduced the invasion ability and anchorage-independent growth of BGC-823 cells in a dose-dependent manner (P < 0.005, P < 0.005). Treatment with quercetin down-regulated MMP-2 mRNA and protein expression in a time- and dose-dependent manner (P < 0.001, P < 0.001).

CONCLUSION: Quercetin inhibits the invasion of human gastric carcinoma cell line BGC-823 possibly by down-regulating MMP-2 expression.

The validation of matrix metalloproteinase-9 mRNA gene expression as a predictor of outcome in patients with metastatic gastric cancer

BACKGROUND

The prognostic role of matrix metalloproteinase-9 (MMP-9) in metastatic gastric cancer has not been validated.

PATIENTS AND METHODS

We carried out a molecular analysis in 222 metastatic gastric cancer patients obtained from clinical trials. We assessed the messenger RNA (mRNA) expression of MMP-9, vascular endothelial growth factor receptor-A, and epidermal growth factor receptor in a training cohort of 130 patients and conducted an independent validation in 92 patients. Automated RNA extraction from paraffin and RT-quantitative PCR was used. Immunohistochemistry for MMP-9 and diverse immune cell infiltrates was conducted.

RESULTS

In the training cohort, only MMP-9 significantly correlated with patient's survival. At the cut-off with the highest predictive value, 19% of patients had MMP-9 expression above this cut-off and these showed a median survival of 3.6 months compared with 10.5 months (P=1.7e(-6)) in patients with lower expression. Corresponding 1- and 2-year survivals were 9% and 44% and 0 and 21%, respectively. The application of this cut-off to the validation cohort revealed similar distributions of overall survival according to MMP-9 expression on uni- (P<0.001) and multivariate analyses (P<0.001). No differences in survival according to MMP-9 below best cut-off were found. MMP-9 protein assessed by immunohistochemistry was not prognostic.

CONCLUSION

MMP-9 mRNA expression above a certain cut-off level is associated with dismal survival.

Prognostic significance of cyclooxygenase-2, epidermal growth factor receptor 1, and microvascular density in gastric cancer

Gastric cancer remains a significant global health burden with poor treatment outcome. New treatment modalities that target inflammation, proliferation, and angiogenesis have been used in various cancers, including gastric cancer. We sought to study the pattern of expression of two important proteins, cyclooxygenase-2 and epidermal growth factor receptor, and their association with microvascular density, clinicopathological features, and survival in Arab Omani patients with gastric cancer. Formalin-fixed, paraffin-embedded tumors were studied by immunohistochemistry using monoclonal antibodies to cyclooxygenase-2, epidermal growth factor receptor, and CD34. The immunohistochemical results were correlated with clinicopathological features and survival. In our study population, we found a male/female ratio of 72:43, a median age of 59 years, stage III and IV incidence of 66.9%, and a median follow-up of 96 months. Positive expression rates of cyclooxygenase-2 and epidermal growth factor receptor were 89.6 and 23.5%, respectively. The median microvascular density value was 52.5. When this value was determined as the cut-off point, 50% of patients were found to have high microvascular density. Epidermal growth factor receptor over-expression correlated with high microvascular density values, advanced lymph node involvement (N3), and TNM stage presentation (III and IV). Similarly, lymph node involvement was associated with cyclooxygenase-2 over-expression and high microvascular density. Univariate analysis showed that epidermal growth factor receptor over-expression, pathological T3 and T4 disease, and overall stage III and IV disease were adverse prognostic factors. On multivariate analysis using a Cox regression model, expression of epidermal growth factor receptor, and advanced TNM stage were significant adverse prognostic factors for overall survival. Expression of epidermal growth factor receptor in Arab Omani patients with gastric cancer correlates with aggressive tumor characteristics and is an independent prognostic factor. Further clinical studies are needed to evaluate the utility of epidermal growth factor receptor immunohistochemistry as a tool for gastric cancer treatment.

Identification of MMP-9 specific microRNA expression profile as potential targets of anti-invasion therapy in glioblastoma multiforme

The poor prognosis of glioblastoma multiforme (GBM) is largely attributed to their highly invasive nature and MMP-9 plays a pivotal role in regulating invasiveness of malignant glioma cells. MicroRNAs (miRNAs) are small non-coding RNAs that have been shown to regulate a wide range of biological processes via targeting messenger RNA. Previous reports have shown many oncogenes regulate survival and invasion via targeting MMP-9 in GBM. But no literature indicates that miRNAs regulate glioma cell invasion through targeting MMP-9. Here, we show MMP-9 overexpression conferred a poor prognosis in 163 GBM patients. Furthermore, MMP-9 specific miRNA expression profile (14 positively and 31 negatively correlated miRNAs with MMP-9) was established via miRNA microarrays in 60 GBM samples. Among them, two miRNAs: miR-885-5p and miR-491-5p, were chosen for functional validation for their high positive correlation with MMP-9 expression. And upregulation of miR-885-5p and miR-491-5p were demonstrated to reduce the levels of MMP-9 expression and inhibit cellular invasion in U251 and U87 glioma cells. Furthermore, we found that miR-491-5p suppressed glioma cell invasion via targeting MMP-9 directly. To our knowledge, this is the first study to identify the MMP-9 specific microRNA signature which may provide potential targets for anti-invasion therapy in GBM.

Gastric cancer stem-like cells possess higher capability of invasion and metastasis in association with a mesenchymal transition phenotype

Cancer stem cells have been isolated from various types of cancer including leukemia and solid tumors. However, the methods for isolating gastric cancer stem-like cells (GCSCs) have not been well established. As a consequence, the biological behavior and the significance of these cells to cancer progression remains to be clarified. In this study, we isolated and characterized GCSCs from a gastric cancer cell line SGC7901 and found their enhanced capabilities of invasion in vitro and metastasis in vivo. We further studied the expression of molecules related to epithelial-mesenchymal and invasion in GCSCs and found there were decreased E-cadherin, but increased vimentin and matrix metalloproteinase 2 (MMP-2), in these cells. Our results suggest that decreased E-cadherin and increased MMP-2 may be associated with the capacity of GCSCs to metastasize.

Clinical impact of MMP and TIMP gene polymorphisms in gastric cancer

BACKGROUND

Recent studies suggest that single-nucleotide polymorphisms (SNPs) within matrix metalloproteinase (MMP) genes and genes of tissue inhibitors of metalloproteinases (TIMPs) have an impact on the expression of these genes and on the prognosis for gastric cancer.

METHODS

Genomic DNA was extracted from paraffin-embedded tissues of 135 patients who were treated surgically for primary gastric carcinoma. Genotyping was performed for MMP-2(-1306C>T), TIMP-2(303C>T), and MMP-7(-181A>G). MMP-2 and TIMP-2 antigen expression in resected tumor tissues was detected immunohistochemically. Genotyping was correlated with antigen expression, histopathologic parameters, and prognosis.

RESULTS

The SNPs did not correlate with tumor differentiation, pT, R category, or the classifications according to the International Union Against Cancer (UICC), the World Health Organization (WHO), and Laurén and Ming. A significant correlation was observed for TIMP-2(303C>T) with higher pN stages (p = 0.01) and more distant metastasis (p = 0.02) for patients with the CC genotypes. In univariate analysis, patients with the TIMP-2(303C>T) CC genotype had an inferior survival, that was not significant (p = 0.2). However, among the gastric cancer patients in the present study, MMP-2(-1306C>T) significantly correlated with gender, with men having more CC genotypes than women (p = 0.025). There were no significant correlations between genotype and protein levels of MMP-2 (p = 0.766) and TIMP-2 (p = 0.684).

CONCLUSIONS

The TIMP-2(303C>T) CC genotype is associated with higher pN and pM categories and, in contrast to previous studies, with worse survival in gastric cancer.

Comparative enzyme immunoassay of matrix metalloproteinases-2, -7, -9 and their tissue inhibitor-2 in tumors and plasma of patients with gastric cancer

The content of matrix metalloproteinases (MMP) -2, -7, and -9 was significantly higher in tumors in comparison with the adjacent histologically intact gastric mucosa in 80, 70, and 72% patients with gastric cancer, respectively, the increase in the level of MMP tissue inhibitor-2 (TIMP-2) detected in 61% tumors was insignificant. Only plasma level of MMP-7 was elevated in primary patients in comparison with the control and positively correlated with the expression of this protein in the tumor. The concentration of MMP-7 was maximum in the blood of patients with tumor invasion in lymph vessels. These data suggest MMP-7 as a possible serological marker of gastric cancer.

Matrix metalloproteinase-9 is associated with disease-free survival and overall survival in patients with gastric cancer

Matrix metalloproteinase-9 is a member of the Matrix metalloproteinases (MMP) family, which is overexpressed in some solid tumor and thought to enhance the tumor invasion and metastasis ability. Our study is to investigate the association of MMP-9 expression with disease-free survival and overall survival of patients with gastric cancer. Clinical gastric cancer specimens and adjacent normal tissues from 286 patients who had not received neoadjuvant chemotherapy were investigated by immunohistochemistry assay. Staining evaluation results were analyzed statistically in relation to various clinicopathological characters, disease-free survival and overall survival. High level of MMP-9 expression was detected in gastric cancer, significantly more than in adjacent normal epithelial cells. In gastric cancer, MMP-9 was significantly positively correlated with depth of invasion, lymph node metastasis and distant metastasis. However, no correlations between MMP-9 expression and patients' age, sex, tumor location or differentiation status were detected. The disease-free survival and overall survival were significantly shorter for patients with MMP-9 positive than those with MMP-9 negative tumors. Multivariate analysis identified MMP-9 was an independent prognostic factor for both disease-free survival and overall survival. Our findings provided convincing evidence for MMP-9 as an important role in human gastric cancer recurrence and prognosis. It might also serve as a novel target for both prognostic prediction and therapeutics.

Regulation of MMP-2 expression and activity by β-1,3-N-acetylglucosaminyltransferase-8 in AGS gastric cancer cells

β-1,3-N-acetylglucosaminyltransferase-8(β3Gn-T8) catalyzes the transfer of GlcNAc to the non-reducing terminus of the Galβ1-4GlcNAc of tetraantennary N-glycan in vitro. It has been reported to be involved in malignant tumors, but a comprehensive understanding of how the glycolsyltransferase correlates with the invasive potential of human gastric cancer is not currently available. Therefore, we investigated the ability and possible mechanism involved with β3Gn-T8 in modulating matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2) in AGS gastric cancer cells. Here, we found out that siRNA-mediated suppression of the β3Gn-T8 could directly reduce the MMP-2 expression and activity as observed in RT-PCR, western blot and gelatin zymography analysis. Meanwhile, TIMP-2 expression had been increased. Cell invasion assay using matrigel matrix-coated transwell inserts showed that the invasive property was greatly suppressed in β3Gn-T8 siRNA transfected cells. Furthermore, cells overexpressing β3Gn-T8 gene (when transfected with pEGFP-C1 plasmid) also expressed MMP-2 gene, but TIMP-2 expression had been inhibited. The invasive ability of these cells was also enhanced. Protein-protein interaction analysis using STRING database showed that β3Gn-T8 and MMP-2 may have related signal pathway. In summary, our results reveal a new mechanism by which β3Gn-T8 can regulate MMP-2 and TIMP-2. We suggest that β3Gn-T8 can be used as a novel therapeutic target for human gastric treatment.

Expression of matrix metalloproteinases 2 and 9 in human gastric cancer and superficial gastritis

AIM: To assess expression of matrix metalloproteinases 2 (MMP2) and MMP9 in gastric cancer, superficial gastritis and normal mucosa, and to measure metalloproteinase activity.

METHODS: MMP2 and MMP9 mRNA expression was determined by quantitative real-time polymerase chain reaction. Normalization was carried out using three different factors. Proteins were analyzed by quantitative gelatin zymography (qGZ).

RESULTS: 18S ribosomal RNA (18SRNA) was very highly expressed, while hypoxanthine ribosyltransferase-1 (HPRT-1) was moderately expressed. MMP2 was highly expressed, while MMP9 was not detected or lowly expressed in normal tissues, moderately or highly expressed in gastritis and highly expressed in cancer. Relative expression of 18SRNA and HPRT-1 showed no significant differences. Significant differences in MMP2 and MMP9 were found between cancer and normal tissue, but not between gastritis and normal tissue. Absolute quantification of MMP9 echoed this pattern, but differential expression of MMP2 proved conflictive. Analysis by qGZ indicated significant differences between cancer and normal tissue in MMP-2, total MMP-9, 250 and 110 kDa bands.

CONCLUSION: MMP9 expression is enhanced in gastric cancer compared to normal mucosa; interpretation of differential expression of MMP2 is difficult to establish.

Tumor suppressor HLJ1 binds and functionally alters nucleophosmin via activating enhancer binding protein 2alpha complex formation

HLJ1, a member of the heat shock protein 40 chaperone family, is a newly identified tumor suppressor that has been implicated in tumorigenesis and metastasis in non-small cell lung cancer. However, the mechanism of HLJ1 action is presently obscure. In this study, we report that HLJ1 specifically interacts with the nuclear protein nucleophosmin (NPM1), forming a multiprotein complex that alters the nucleolar distribution and oligomerization state of NPM1. Enforced accumulation of NPM1 oligomers by overexpression in weakly invasive but high HLJ1-expressing cells induced the activity of signal transducer and activator of transcription 3 (STAT3) and increased cellular migration, invasiveness, and colony formation. Furthermore, silencing HLJ1 accelerated NPM1 oligomerization, inhibited the activity of transcription corepressor activating enhancer binding protein 2alpha (AP-2alpha), and increased the activities of matrix metalloproteinase-2 (MMP-2) and STAT3. Our findings suggest that HLJ1 switches the role of NPM1, which can act as tumor suppressor or oncogene, by modulating the oligomerization of NPM1 via HLJ1-NPM1 heterodimer formation and recruiting AP-2alpha to the MMP-2 promoter.

COX-2 is associated with proliferation and apoptosis markers and serves as an independent prognostic factor in gastric cancer

Cyclooxygenase-2 (COX-2) is an important factor in gastric carcinogenesis, and COX-2 expression in gastric cancer patients correlates with prognosis. We have now studied the impact of COX-2 in comparison to six other tissue tumor markers, DNA index, and S-phase fraction (SPF) in a large series of gastric cancer specimens. From 342 consecutive patients, 337 archival tissue specimens were available for immunohistochemistry of COX-2, HuR, cyclin A, MMP-2, p53, p21, and Ki-67 and 313 for analysis of DNA index and S-phase fraction by flow cytometry. Associations between factors were assessed by chi-square test and survival analysis by the Kaplan-Meier method and Cox model. A significant association emerged between of COX-2 and p53 (p < 0.0001), Ki-67 (p = 0.013), DNA ploidy (p < 0.0001), and SPF (p < 0.0001). In an extended multivariate analysis, COX-2 and p53 expression were independent prognostic factors for poor survival, in addition to high stage and non-curative surgery. In gastric cancer, COX-2 expression associated with markers for apoptosis and proliferation, and furthermore, it was confirmed that COX-2 and p53 are strong prognostic indicators.

Molecular aspects in the diagnosis of gastric cancer

BACKGROUND

Gastric cancer (GC) represents the second most common cause of cancer-related death worldwide. The prognosis remains poor, with limited treatment options. A better understanding of the initiation and progression of GC would enable the development of general screening strategies and individualized treatment modalities.

OBJECTIVE

The assessment of tools and molecular markers for the early detection and diagnosis of GC.

METHODS

Human clinical studies published within the past 5 years are reviewed. Also, significant previous data on markers in clinical use or on relevant animal or cell culture experiments are considered.

RESULTS/CONCLUSION

Serum-based screening strategies are not ready for routine application but represent an opportunity for the identification of individuals at high risk with the need for primary gastroscopy and further surveillance, which would ultimately improve survival and prognosis of GC. Infection with Helicobacter pylori represents the principal risk factor for gastric carcinogenesis. Bacterial virulence and host genetic factors contribute to individual susceptibility. Key molecular alterations in gastric carcinogenesis are related to intra- and extracellular cascades that regulate cell proliferation, tumor invasion and metastastic spread. For the development of effective prevention and treatment modalities, it is essential to unravel the basic mechanisms of gastric carcinogenesis.

Matrix metalloproteinase-2 expression in stromal tissues is a consistent prognostic factor in stage II colon cancer

For patients with stage II colon cancer, the usefulness of adjuvant chemotherapy remains controversial. Therefore, it is important to identify high-risk indicators. The biological prognostic factors for recurrence might allow further insight into the optimal treatment strategy for patients with node-negative disease. Matrix metalloproteinase-2 seems to be one of the essential factors for tumor invasion and lymph node metastasis. In this study, we analyzed the expression of cyclooxygenase-2 and matrix metalloproteinase-2 by immunohistochemical staining in 109 patients with stage II colon cancer. A positive correlation was observed between tumor cyclooxygenase-2 and tumor matrix metalloproteinase-2 expression (P = 0.0006) and between tumor cyclooxygenase-2 and stromal matrix metalloproteinase-2 expression (P < 0.0001). Stromal matrix metalloproteinase-2 expression was associated with disease-free survival (P = 0.0095) and was shown to be an independent risk factor for recurrence by multivariate analysis. In addition, we carried out an invasion assay in vitro to investigate whether cyclooxygenase-2 and matrix metalloproteinase-2 affected the tumor-invasive potential of colon cancer cell lines. The invasion assay showed that every cancer cell line acquired invasive potential in coculture with stromal cell lines and the cyclooxygenase-2 inhibitor suppressed this phenomenon by downregulating the matrix metalloproteinase-2 expression of stromal cells. In conclusion, these findings suggest that matrix metalloproteinase-2 expression in stromal cells can be a high-risk indicator for recurrence in patients with stage II colon cancer.

Enhanced systemic matrix metalloproteinase response in Helicobacter pylori gastritis

BACKGROUND

Helicobacter pylori causes chronic gastritis, peptic ulcer disease, and is the most important risk factor for non-cardia gastric cancer, and has been shown to upregulate matrix metalloproteinases (MMPs) in infected gastric mucosa. MMPs are proteolytic enzymes regulated by tissue inhibitors of metalloproteinases (TIMPs).

AIMS

We set up this study to find out whether H. pylori gastritis induces systemic MMP response.

METHODS

Serum samples were collected from patients undergoing gastroscopy; 26 patients had H. pylori gastritis and 18 were H. pylori-negative controls with normal gastric mucosa. Serum MMP levels were analysed by enzyme-linked immunosorbent assay.

RESULTS

Significantly elevated serum levels of collagenase-2 (MMP-8), gelatinase B (MMP-9), neutrophil elastase (NE), and myeloperoxidase (MPO), and reduced serum levels of gelatinase A (MMP-2) and TIMP-1 were demonstrated in patients with H. pylori gastritis as compared to H. pylori-negative controls. No significant differences were shown in serum matrilysin-1 (MMP-7) levels.

CONCLUSIONS

For the first time, we show enhanced MMP-8 response in H. pylori infection together with other neutrophil degranulation products (MMP-9, MPO, NE). Elevated circulating neutrophil degranulation product levels in serum of H. pylori-positive patients reflect accelerated proteolysis and oxidative stress, and may contribute to extraintestinal sequelae, such as cardiovascular diseases.

Associations of matrix metalloproteinase-9 protein polymorphisms with lymph node metastasis but not invasion of gastric cancer

PURPOSE

Like most cancers, gastric cancer has a complex multistep etiology that involves both environmental and genetic factors. Matrix metalloproteinase-9 (MMP-9) is frequently overexpressed in gastric cancer. We investigated the effect of the genetic differences in MMP-9 coding region on the occurrence and progression of gastric cancer.

EXPERIMENTAL DESIGN

A case-control study was conducted in a population of 74 patients and 100 healthy people in southeast China. Individuals were genotyped for two single nucleotide polymorphisms (SNP) in MMP-9: R279Q and P574R. Genotypic distributions between patient and control groups were compared for correlations with cancer occurrence. Associations between genotypic distributions and several clinicopathologic features were also analyzed using univariate tests, multivariate logistic regression modeling, and stratified analyses.

RESULTS

Significant associations were revealed between both SNPs and lymph node metastasis [P = 0.012 and 0.025; odds ratio (OR), 3.4 and 2.8, respectively]. After adjustment using logistic regression for the potential confounding effects of gender, age, and location of the tumors, homozygous MMP-9 279RR and 574PP are more evidently associated with lymph node metastasis with OR(adjusted) of 5.7 [95% confidence interval (95% CI), 1.80-18.34] and 4.2 (95% CI, 1.37-12.69). The homozygous 279R-574P haplotype showed a stronger association by an OR(adjusted) of 6.1 (95% CI, 1.92-12.29) and was also associated with the 1-year postoperative mortality (OR(adjusted), 6.5; 95% CI, 1.18-35.74). Interestingly, our data also suggested that the MMP-9 polymorphisms seem to result in higher risk of lymph node metastasis through a pathway independent of cancer invasion because no positive associations were found between these polymorphisms and cancer invasion (OR, 0.59 < 1). The stratified analyses indicated a synergistic interaction between the MMP-9 polymorphisms and the type of diffuse in affecting lymph node metastasis (OR, 13.4; P(between strata) = 0.04). Significant association between both SNPs and the overall occurrence of gastric cancer was not observed.

CONCLUSION

The present study has shown significant associations between the two nonsynonymous MMP-9 polymorphisms with lymph node metastasis in gastric cancer, especially with the diffuse type. The relatively large values of ORs and disassociation with cancer invasion suggest that the genetic differences of MMP-9 protein play an important and specific role in lymph node metastases, and therefore, further investigation of the underlying molecular mechanism is warranted.

Recent advances in conventional and molecular prognostic factors for gastric carcinoma

Despite radical surgery, the prognosis of patients who have gastric carcinoma remains unsatisfactory because of the intrinsic but unpredictable aggressiveness of this malignancy. During the past decade an ever-growing list of molecular prognostic factors has been proposed based on the discovery of the mechanisms underlying gastric cancer aggressiveness. Studies performed in larger and more homogeneous series of patients and adequate statistical analysis are warranted before any of the candidate biomarkers can be implemented in the routine clinical setting for the identification of patients at higher risk and thus for the selection of candidates for adjuvant or more aggressive therapies.

High MMP-1 mRNA expression is a risk factor for disease-free and overall survivals in patients with invasive breast carcinoma

BACKGROUND

Matrix metalloproteinase 1 (MMP-1) degrades extracellular matrix and thereby promotes tumor invasion and progression. In this study we examined the prognostic significance of tissue expression levels of MMP-1 mRNA in patients with invasive breast carcinoma.

MATERIALS AND METHODS

We assessed the prognostic value of MMP-1 mRNA expression in tumor tissue specimens from 85 breast carcinoma patients with a median follow-up time of 38 months (range, 2-48 months). MMP-1 mRNA levels were measured by real-time quantitative reverse transcriptase polymerase chain reaction (real time RT-PCR). The results were correlated with various clinicopathological parameters and clinical outcomes.

RESULTS

mRNA expression levels of MMP-1 were higher in tumor tissue specimens than in adjacent normal breast tissue specimens from 15 patients (P < 0.023). MMP-1 mRNA levels showed no significant relationship with either tumor size or axillary node status but correlated inversely with estrogen receptor levels (P < 0.0043). High MMP-1 mRNA expression as determined by real-time RT-PCR correlated significantly with a high frequency of recurrence and fatal outcome (P < 0.025 and P < 0.020). Multivariate analysis using the Cox regression model indicated that high MMP-1 mRNA expression was an independent unfavorable prognostic factor (risk ratio, 6.37; P < 0.019).

CONCLUSIONS

We have demonstrated for the first time the high mRNA expression of MMP-1 in patients whose carcinomas lack estrogen receptor expression. Our results suggest that MMP-1 is an important gene implicated in the progression of human breast cancer.

Expression of nuclear factor kappaB in human gastric carcinoma: relationship with I kappaB a and prognostic significance

Nuclear factor (NF)-kappaB is a transcription factor constitutively activated in various neoplasms, including gastric carcinoma. However, its clinical significance in the latter remains an unresolved issue, as published information is limited and controversial. Furthermore, no data is available about the interaction of NF kappaB with its inhibitory protein I kappaB a in gastric carcinoma cases. In this study, the expression of NF kappaB 1/p50 and p I kappaB a protein was evaluated immunohistochemically in paraffin-embedded tissues from 93 patients. The effect of NF kappaB 1/p50 and p I kappaB a on clinical outcome was assessed. Positive immunostaining was detected for nuclear NF kappaB 1/p50, cytoplasmic NF kappa B1/p50 and p I kappaB a in 91, 68 and 85.7% of cases, respectively. A positive correlation emerged between nuclear NF kappa B 1/p50 and p I kappaB a (p < 0.0001) and a negative one between cytoplasmic NF kappaB 1/p50 and p I kappaB a (p = 0.0033). Nuclear NF kappaB 1/p50 was associated with stage (p = 0.0388), the depth of invasion (p = 0.0382), World Health Organization (WHO; p = 0.0326) and Lauren's histological classification (p = 0.0046). NF kappaB 1/p50 nuclear expression adversely affected survival in both univariate and multivariate analysis (p < 0.0001 and p = 0.02, respectively). Our results suggest that NF kappaB 1/p50 nuclear expression and therefore activation is regulated by its interaction with I kappaB a and that the former may serve as a useful independent molecular marker for stratifying patients with gastric carcinoma in terms of prognosis.