Immunohistochemical detection of membrane-type-1-matrix metalloproteinase in colorectal carcinoma

The differential cancer growth associated with anaesthetics in a cancer xenograft model of mice: mechanisms and implications of postoperative cancer recurrence

Anaesthetics may modify colorectal cancer cell biology which potentially affects long-term survival. This study aims to compare propofol and sevoflurane regarding with the direct anaesthetic effects on cancer malignancy and the indirect effects on host immunity in a cancer xenograft mode of mice. Cultured colon cancer cell (Caco-2) was injected subcutaneously to nude mice (day 1). Mice were exposed to either 1.5% sevoflurane for 1.5 h or propofol (20 μg g-1; ip injection) with or without 4 μg g-1 lipopolysaccharide (LPS; ip) from days 15 to 17, compared with those without anaesthetic exposure as controls. The clinical endpoints including tumour volumes over 70 mm3 were closely monitored up to day 28. Tumour samples from the other cohorts were collected on day 18 for PCR array, qRT-PCR, western blotting and immunofluorescent assessment. Propofol treatment reduced tumour size (mean ± SD; 23.0 ± 6.2mm3) when compared to sevoflurane (36.0 ± 0.3mm3) (p = 0.008) or control (23.6 ± 4.7mm3). Propofol decreased hypoxia inducible factor 1α (HIF1α), interleukin 1β (IL1β), and hepatocyte growth factor (HGF) gene expressions and increased tissue inhibitor of metalloproteinases 2 (TIMP-2) gene and protein expression in comparison to sevoflurane in the tumour tissue. LPS suppressed tumour growth in any conditions whilst increased TIMP-2 and anti-cancer neutrophil marker expressions and decreased macrophage marker expressions compared to those in the LPS-untreated groups. Our data indicated that sevoflurane increased cancer development when compared with propofol in vivo under non-surgical condition. Anaesthetics tested in this study did not alter the effects of LPS as an immune modulator in changing immunocyte phenotype and suppressing cancer development.

Comprehensive Analysis of the Expression and Prognosis for MMPs in Human Colorectal Cancer

Background

Previous study implicated that genes of matrix metalloproteinase (MMP) family play an important role in tumor invasion, neoangiogenesis, and metastasis. However, the diverse expression patterns and prognostic values of 24 MMPs in colorectal cancer are yet to be analyzed.

Methods

In this study, by integrating public database and our data, we first investigated the expression levels and protein levels of MMPs in patients with colorectal cancer. Then, by using TCGA and GEO datasets, we evaluated the association of MMPs with clinicopathological parameters and prognosis of colorectal cancer. Finally, by using the cBioPortal online tool, we analyzed the alterations of MMPs and did the network and pathway analyses for MMPs and their nearby genes.

Results

We found that, MMP1, MMP3, MMP7, MMP9–MMP12, and MMP14 were consistently upregulated in public dataset and our samples. Whereas, MMP28 was consistently downregulated in public dataset and our samples. In the clinicopathological analyses, upregulated MMP11, MMP14, MMP16, MMP17, MMP19, and MMP23B were significantly associated with a higher tumor stage. In the survival analyses, upregulated MMP11, MMP14, MMP17, and MMP19 were significantly associated with a shorter progression-free survival (PFS) time and a shorter relapse-free (RFS) time.

Discussion

This study implied that MMP11, MMP14, MMP17, and MMP19 are potential targets of precision therapy for patients with colorectal cancer.

Strong association of tissue inhibitor of metalloproteinase (TIMP)-2 and -3 promoter single nucleotide polymorphisms with risk of colorectal cancer in ethnic Kashmiri population - a case control study

Background: The tissue inhibitors of metalloproteinases (TIMPs) including TIMP2 and TIMP3 are the key physiological inhibitors of matrix metalloproteinases (MMPs) and along with MMPs, TIMPs play a vital role in the coordinated proteolytic breakdown and remodeling of the extracellular matrix (ECM) and the basement membrane that represent the barriers to any malignant tumor invasion and progression. These enzymes are vital for tumor invasion and metastasis and also play a critical role in several other stages of tumor development and progression. The studies on the association of various polymorphisms in human TIMP2 and TIMP3 genes including TIMP2-418G/C and TIMP3-1296T/C single nucleotide polymorphisms (SNPs) and CRC risk are limited, mixed, and inconclusive.Materials and methods: The aim of the present study was to analyze the association of TIMP2-418G/C and TIMP3-1296T/C promoter SNPs with colorectal cancer (CRC) susceptibility and development risk and also to evaluate the modifying effects of possible TIMP2-418G/C and TIMP3-1296T/C SNPs' genotypes on different risk factors of CRC or the reciprocal effect in ethnic population of Kashmir, India through a case-control setup. The genotype frequencies of TIMP2-418G/C and TIMP3-1296T/C promoter SNPs were compared between 142 CRC patients and 184 individually matched healthy controls by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The associations between the TIMP2-418G/C and TIMP3-1296T/C SNPs and CRC risk were examined through conditional logistic regression models adjusted for multiple possible confounding (third) variables. The possible effect measure modification of the association between the relevant SNP genotypes and CRC risk by various CRC risk factors including age, gender, and smoking status was also analyzed. Further, the associations between these SNPs and various clinico-pathological parameters, demographic variables, and environmental factors within the case group subjects with regard to CRC risk were also evaluated.Results: The overall association between the TIMP2-418G/C and TIMP3-1296T/C SNPs and the modulation of CRC risk was found to be highly significant (P=0.019 and P=0.000 for TIMP2 and TIMP3 SNPs, respectively). The heterozygous genotype (GC) of TIMP2-418G/C was significantly associated with an increased risk of colorectal cancer [OR, 1.87 (95%CI, 1.07-3.27); P=0.027] whereas the heterozygous genotype (TC) of TIMP3-1296T/C SNP was significantly associated with a decreased risk of colorectal cancer [OR, 0.53 (95%CI, 0.32-0.86); P=0.011]. The variant genotype (CC) of TIMP3-1296T/C SNP was also significantly associated with a decreased risk of colorectal cancer [OR, 0.18 (95%CI, 0.05-0.65); P=0.009].Conclusion: The present study demonstrates that there is a strong and highly significant association between the TIMP2-418G/C and TIMP3-1296T/C promoter SNPs and the risk of developing CRC in ethnic Kashmiri population. However, in order to substantiate our findings, the present study needs to be replicated with bigger sample size and should involve other ethnically defined populations with high CRC risk.

Targeting the MMP-14/MMP-2/integrin αvβ3 axis with multispecific N-TIMP2-based antagonists for cancer therapy

The pathophysiological functions of the signaling molecules matrix metalloproteinase-14 (MMP-14) and integrin α_vβ₃ in various types of cancer are believed to derive from their collaborative activity in promoting invasion, metastasis, and angiogenesis, as shown in vitro and in vivo The two effectors act in concert in a cell-specific manner through the localization of pro-MMP-2 to the cell surface, where it is processed to intermediate and matured MMP-2. The matured MMP-2 product is localized to the cell surface via its binding to integrin α_vβ₃ The MMP-14/MMP-2/integrin α_vβ₃ axis thus constitutes an attractive putative target for therapeutic interventions, but the development of inhibitors that target this axis remains an unfulfilled task. To address the lack of such multitarget inhibitors, we have established a combinatorial approach that is based on flow cytometry screening of a yeast-displayed N-TIMP2 (N-terminal domain variant of tissue inhibitor of metalloproteinase-2) mutant library. On the basis of this screening, we generated protein monomers and a heterodimer that contain monovalent and bivalent binding epitopes to MMP-14 and integrin α_vβ₃ Among these proteins, the bi-specific heterodimer, which bound strongly to both MMP-14 and integrin α_vβ₃, exhibited superior ability to inhibit MMP-2 activation and displayed the highest inhibitory activity in cell-based models of a MMP-14-, MMP-2-, and integrin α_vβ₃-dependent glioblastoma and of endothelial cell invasiveness and endothelial capillary tube formation. These assays enabled us to show the superiority of the combined target effects of the inhibitors and to investigate separately the role each of the three signaling molecules in various malignant processes.

Lack of Association between Membrane-Type 1 Matrix Metalloproteinase Expression and Clinically Relevant Molecular or Morphologic Tumor Characteristics at the Leading Edge of Invasive Colorectal Carcinoma

Colorectal cancer (CRC) is one of the leading causes of death from cancer in the western world, but tumor biology and clinical course show great interindividual variation. Molecular and morphologic tumor characteristics, such as KRAS/BRAF mutation status, mismatch repair (MMR) protein expression, tumor growth pattern, and tumor cell budding, have been shown to be of key therapeutic and/or prognostic relevance in CRC. Membrane-type 1 matrix metalloproteinase (MT1-MMP) is a membrane-anchored zinc-binding endopeptidase that is expressed at the leading edge of various invasive carcinomas and promotes tumor cell invasion through degradation of the extracellular matrix. The aim of this study was to investigate possible associations between MT1-MMP expression and molecular tumor characteristics as well as morphologic features of tumor aggressiveness in a consecutive series of 79 CRC tissue samples. However, although MT1-MMP was expressed in 41/79 samples (52%), there was no significant association between MT1-MMP expression and KRAS/BRAF mutation status, MMR protein expression, presence of lymphovascular invasion, tumor growth pattern, tumor-infiltrating lymphocytes, or tumor cell budding in our sample cohort (P > 0.05). Thus, we conclude that although MT1-MMP may play a role in CRC invasion, it is not of key relevance to the current models of CRC invasion and aggressiveness.

LIN28 cooperates with WNT signaling to drive invasive intestinal and colorectal adenocarcinoma in mice and humans

LIN28A and LIN28B are highly related RNA-binding paralogs that influence development, tissue regeneration, and oncogenesis. Tu et al. demonstrate that overexpression of either paralog drives invasive intestinal adenocarcinoma and cooperates with the Wnt pathway to promote tumor initiation and progression in murine models.

Colorectal cancer (CRC) remains a major contributor to cancer-related mortality. LIN28A and LIN28B are highly related RNA-binding protein paralogs that regulate biogenesis of let-7 microRNAs and influence development, metabolism, tissue regeneration, and oncogenesis. Here we demonstrate that overexpression of either LIN28 paralog cooperates with the Wnt pathway to promote invasive intestinal adenocarcinoma in murine models. When LIN28 alone is induced genetically, half of the resulting tumors harbor Ctnnb1 (β-catenin) mutation. When overexpressed in Apc^Min/+ mice, LIN28 accelerates tumor formation and enhances proliferation and invasiveness. In conditional genetic models, enforced expression of a LIN28-resistant form of the let-7 microRNA reduces LIN28-induced tumor burden, while silencing of LIN28 expression reduces tumor volume and increases tumor differentiation, indicating that LIN28 contributes to tumor maintenance. We detected aberrant expression of LIN28A and/or LIN28B in 38% of a large series of human CRC samples (n = 595), where LIN28 expression levels were associated with invasive tumor growth. Our late-stage CRC murine models and analysis of primary human tumors demonstrate prominent roles for both LIN28 paralogs in promoting CRC growth and progression and implicate the LIN28/let-7 pathway as a therapeutic target.

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.

Active matrix metalloproteinase-2 activity discriminates colonic mucosa, adenomas with and without high-grade dysplasia, and cancers

Pathologic assessment of colorectal adenomas, a complex task with significant interobserver variability, typically defines the scheduling of surveillance colonoscopies after removal of adenomas. We have characterized the activity levels of pro-matrix metalloproteinase-2, active matrix metalloproteinase-2, and matrix metalloproteinase-9 in colorectal adenomas and carcinomas as potential markers of pathologic progression during colorectal tumorigenesis. Endogenous fully activated matrix metalloproteinase-2, in particular, has been studied less frequently in adenomas due to difficulties in detection. For this report, tissues (n = 119) from 51 individuals were extracted and assayed on gelatin zymograms with digital standardization to nanogram quantities of purified active controls. Resulting data were assessed by graphical and multinomial logit regression analyses to test whether matrix metalloproteinase-2 or matrix metalloproteinase-9 activities could discriminate among 4 different types of colorectal tissue (normal mucosa, adenomas with or without high-grade dysplasia, and invasive carcinomas). Active matrix metalloproteinase-2 successfully discriminated among these tissue categories. Median activity for active matrix metalloproteinase-2 increased in a stepwise fashion with pathologic progression from normal mucosa to adenoma without high-grade dysplasia to adenoma with high-grade dysplasia to cancer. Although pro-matrix metalloproteinase-2 and pro-matrix metalloproteinase-9 activities could discriminate to some extent among tissue categories, those effects did not contribute additional information. Active matrix metalloproteinase-2 activity correlated significantly with histopathologic assessment of colorectal tissues. The ability of active matrix metalloproteinase-2 to distinguish adenomas with high-grade dysplasia from adenomas without high-grade dysplasia may be particularly useful in predicting future colorectal cancer risk for an individual, thus optimizing scheduling of surveillance colonoscopies.

Cell surface markers in colorectal cancer prognosis

The classification of colorectal cancers (CRC) is currently based largely on histologically determined tumour characteristics, such as differentiation status and tumour stage, i.e., depth of tumour invasion, involvement of regional lymph nodes and the occurrence of metastatic spread to other organs. These are the conventional prognostic factors for patient survival and often determine the requirement for adjuvant therapy after surgical resection of the primary tumour. However, patients with the same CRC stage can have very different disease-related outcomes. For some, surgical removal of early-stage tumours leads to full recovery, while for others, disease recurrence and metastasis may occur regardless of adjuvant therapy. It is therefore important to understand the molecular processes that lead to disease progression and metastasis and to find more reliable prognostic markers and novel targets for therapy. This review focuses on cell surface proteins that correlate with tumour progression, metastasis and patient outcome, and discusses some of the challenges in finding prognostic protein markers in CRC.

Relation of MT1-MMP gene expression to outcomes in colorectal cancer

BACKGROUND

Matrix metalloproteinases are members of a large family of endopeptidases that participate in the extracellular-matrix degradation that accompanies cancer cell invasion, metastasis and angiogenesis. The membrane-type 1 matrix metalloproteinase (MT1-MMP) gene has been reported in various cancers and is associated with tumor invasion and metastasis. This study examined the relation of the relative expression of MT1-MMP gene to clinicopathological factors and outcomes in patients with colorectal cancer (CRC).

METHODS

We studied surgical specimens of cancer tissue and adjacent normal mucosa obtained from 202 patients with untreated CRC. The relative expression levels of MT1-MMP mRNA in cancer and in normal adjacent mucosa were measured by quantitative real-time reverse-transcriptase polymerase chain reaction.

RESULTS

MT1-MMP gene expression was higher in cancer tissue than in adjacent normal mucosa. The level of MT1-MMP gene expression was not related to any clinicopathological factor. Overall survival at 5 years differed significantly between patients with high MT1-MMP gene expression and those with low expression.

CONCLUSIONS

Overexpression of the MT1-MMP gene is considered a useful independent predictor of outcomes in patients with CRC.

New Strategies for the Next Generation of Matrix-Metalloproteinase Inhibitors: Selectively Targeting Membrane-Anchored MMPs with Therapeutic Antibodies

MMP intervention strategies have met with limited clinical success due to severe toxicities. In particular, treatment with broad-spectrum MMP-inhibitors (MMPIs) caused musculoskeletal pain and inflammation. Selectivity may be essential for realizing the clinical potential of MMPIs. Here we review discoveries pinpointing membrane-bound MMPs as mediators of mechanisms underlying cancer and inflammation and as possible therapeutic targets for prevention/treatment of these diseases. We discuss strategies to target these therapeutic proteases using highly selective inhibitory agents (i.e., human blocking antibodies) against individual membrane-bound MMPs.

Expressions of the anti-apoptotic genes Bag-1 and Bcl-2 in colon cancer and their relationship

BACKGROUND

The aims of this study were to investigate the expressions and significance of the antiapoptotic genes Bag-1 and Bcl-2 in colon cancer and to evaluate their relationship.

METHODS

The expressions of Bag-1 and Bcl-2 were examined in 128 colon cancer and 20 normal colon tissue samples by reverse-transcription polymerase chain reaction and immunohistochemical technique (streptavidin-biotin-peroxidase complex method).

RESULTS

Bag-1 and Bcl-2 were expressed in colorectal cancer tissues but not in normal colorectal tissues by reverse-transcription polymerase chain reaction. The expression of Bag-1 in colon cancer was closely correlated with pathologic grade, distance metastasis, Duke stage, and prognosis, but it had no effect on the pathologic type, tumor diameter, depth of invasion, and lymphoid node metastasis of the cancer. By contrast, Bcl-2 had no significant correlation with all the clinical and pathologic factors. There was a positive correlation between Bag-1 and Bcl-2 in the development of colon cancer.

CONCLUSIONS

High expressions of Bag-1 and Bcl-2 proteins in colon cancer were found. They might be regarded as biomarkers for the diagnosis of the early stage of colon cancer. In addition, they have significant relevance for the prognosis of colon cancer.

Immunohistochemically detected high expression of matrix metalloproteinase-2 as predictor of poor prognosis in Duke's B colon cancer

AIM

To demonstrate immunohistochemical expression of matrix metalloproteinase-2 (MMP-2) protein in Duke's B colon cancer and determine its correlation with age, sex, grade, presence of vascular invasion, and patients' overall survival.

METHOD

The study took place from January 1995 to December 1997. We determined the expression of MMP-2 in 152 formalin-fixed, paraffin embedded specimens of Duke's B colon carcinomas by immunohistochemical analysis using MMP-2 monoclonal antibody. Immunohistochemical expression was scored semiquantitatively. Carcinomas were graded as low or high grade. Survival time was analyzed with Kaplan-Meier method, and the log-rank test was used to assess the differences between groups. Cox proportional hazard regression model was used for multivariate survival analysis.

RESULT

Univariate analysis showed that positive staining for MMP-2, high histological grade, vascular invasion, male sex, and age>60 years were associated with shorter survival in patients with Duke's B colon cancer (P range from 0.023 to <0.001). Multivariate analysis showed that only MMP-2 overexpression (P<0.001; hazard ratio [HR]=3.64) and vascular invasion (P<0.001; HR=4.27) were associated with shorter overall survival.

CONCLUSION

Expression of MMP-2 is an important independent indicator of shorter survival in patients with Duke's B colon cancer and should be taken into consideration in decision-making on the use of adjuvant systemic therapy in patients with Duke's B colon cancer.

Matrix metalloproteinase-9 activity is associated with poor prognosis in T3-T4 node-negative colorectal cancer

Reversion-inducing cysteine-rich protein with Kazal motifs (RECK) is a novel membrane-anchored matrix metalloproteinase (MMP) inhibitor. RECK, MMP-2, and MMP-9 are believed to play crucial roles in tumor progression. This study was designed to examine the prognostic value of RECK, MMP-2, and MMP-9 in conjunction with other clinicopathologic factors in patients of T3-T4 node-negative colorectal cancer. RECK and MMP expression was observed using immunohistochemical analysis of the primary tumor from 89 patients with curatively resected T3-4 N0 colorectal cancer retrospectively. High RECK expression was observed in 51 cases, whereas expression was low in the other 38 cases. MMP-2 and MMP-9 expression was positive in cancer cells in 24 and 33 cases, respectively. RECK and MMP-2 expression was not significantly associated with any clinicopathologic factors. However, expression of MMP-9 was correlated with tumor location. A statistically significant inverse correlation was found between RECK and MMP-2 expression, and a statistically significant correlation was found between MMP-2 and MMP-9 expression. However, no association between RECK and MMP-9 expression was observed. Univariate analysis demonstrated that rectal tumor location, preoperative carcinoembryonic antigen more than 5 ng/mL, positive lymphatic invasion, less than 12 dissected lymph nodes, and positive MMP-9 expression were poor prognostic factors of disease-free survival. A multivariate analysis confirmed that enhanced MMP-9 expression was an independent and significant factor for prediction of a poor prognosis. In addition, positive lymphatic invasion and less than 12 dissected lymph nodes were significant negative prognostic factors. In conclusion, MMP-9 status represents a novel prognostic factor in evaluation of T3-T4 node-negative colorectal cancer.

A multivariate analysis of adhesion molecules expression in assessment of colorectal cancer

BACKGROUND AND OBJECTIVES

Adhesion molecules are implicated in the progression of colorectal cancer (CRC). Despite the evidence of association between their expression and patients' prognosis, the data have not been examined simultaneously in a same study; thus, the relative clinical value remained largely unknown. The aim of this study was to identify the adhesion factors that display the most significant prognostic value for CRC patients to guide clinical decision-making regarding appropriate treatment.

PATIENTS AND METHODS

We examined by immunohistochemistry, the expression of E-cadherin and its associated catenins, alpha(alpha)-catenin and beta(beta)-catenin, DCC, and CD44 and its partner, MT1-MMP in a series of 140 CRC tissues at intermediate Stage II and Stage III to determine their prognostic significance.

RESULTS

Clinicopathological survey indicated an inverse relationship between E-cadherin expression and tumor differentiation, and an association between CD44 expression and venous invasion. Univariate and multivariate analyses showed that loss of expression of E-cadherin and CD44 significantly correlated to poor survival, especially in Stage II. Combination studies indicated that loss of E-cadherin and loss of CD44 had the worst impact on patient prognosis, particularly in colon cancer.

CONCLUSION

Immunohistochemical staining of E-cadherin and CD44 may help to identify a subgroup of high-risk patients with Stage II CRC, especially in colon cancer, who may need intensive follow-up and appropriate therapeutic strategy.

Tissue inhibitor of matrix metalloproteinase-2 in nasopharyngeal carcinoma

By regulating matrix metalloproteinase (MMP) activity and controlling the breakdown of extracellular matrix components, tissue inhibitors of metalloproteinases (TIMPs) play an important role in the process of tumor invasion and metastasis. The present study was designed to clarify the role of TIMP-2 in nasopharyngeal carcinoma (NPC) patients and to evaluate its importance relative to clinicopathologic parameters. It was carried out in 30 patients with NPC and 20 controls. Tissue biopsies were studied and graded pathologically, and Western blot analysis was performed to assess TIMP-2 protein expression. Clinically, in accordance with TNM classification (T: tumor size, N: lymph node involvement, M: distant metastasis), 8 cases were diagnosed as stage II, 12 as stage III, and 10 cases as stage IV; however, pathologic typing with use of the World Health Organization (WHO) classification revealed the presence of 9 specimens of squamous cell carcinoma (WHO type 1), 6 cases of nonkeratinizing carcinoma (WHO type 2), and 15 cases of undifferentiated carcinoma (WHO type 3). The difference in percentage of TIMP-2 positivity between NPC patients (76.6%) and normal controls (30%) was statistically highly significant (P < .01). In addition, there was a significant positive correlation between TIMP-2 protein positivity and either the clinical staging or the histopathologic typing (P < .01) using Chi-square test (x(2)), suggesting that TIMP-2 can be used as a marker of the severity of NPC.Accordingly, we can assume that TIMP-2 may play a role in regional lymph node and/or distant metastasis and in progression of squamous cell carcinoma. Further studies are needed to investigate the role of TIMP-2 as a marker for tumor progression and to evaluate its potential value in the follow-up of patients.

Prognostic values of matrix metalloproteinase family expression in human colorectal carcinoma

BACKGROUND

We examined expression patterns of matrix metalloproteinase (MMP), tissue inhibitor of metalloproteinase (TIMP), and reversion-inducing cysteine-rich protein with Kazal motifs (RECK) in colorectal cancer tissues to assess their prognostic significance.

MATERIALS AND METHODS

mRNA expressions of 17 MMPs, 4 TIMPs, and RECK were measured in 112 colorectal cancerous tissues, 20 normal mucosa tissues, and 11 metastatic liver lesions by real-time reverse-transcriptional-polymerase chain reaction. The protein level expressions were confirmed with immunohistochemistry.

RESULTS

Cancers and normal mucosa displayed highly significant differences (P < 0.01) in expression of nine genes (MMP-1, -3, -7, -9, -10, -11, -12, -14, and RECK). Primary cancers and metastatic lesions showed highly significant differences (P < 0.01) in MMP-1, -10, -11, and TIMP-1. MMP-12 expression was higher in the primary tumors that were associated without hepatic metastasis than those with metastasis (P < 0.01). High expression of MMP-15 was related to longer disease-free survival (generalized Wilcoxon test, P < 0.0062; Cox hazard model, P < 0.028, hazard ratio, 0.099).

CONCLUSIONS

MMP, TIMP, RECK expression patterns may provide an insight into extracellular matrix degrading (which is characteristic of colorectal cancers) and its role in metastasis.

Clinicopathologic and prognostic significance of matrix metalloproteinases in rectal cancer

BACKGROUND AND AIMS

The aim of this study was to determine the prognostic role of matrix metalloproteinases in rectal cancer.

MATERIALS AND METHODS

Formalin-fixed and paraffin-embedded tissue sections of 94 rectal carcinomas were used for the immunohistochemical analysis of matrix metalloproteinases (MMP)-2, MMP-7, MT1-MMP, and tissue inhibitor of metalloproteinases (TIMP)-2. Inclusion criteria were sporadic rectal adenocarcinoma resected curatively (including total mesorectal excision), adjuvant radiochemotherapy in UICC stages II and III, and complete intra-institutional follow-up. Results of immunohistochemistry were correlated with clinical and histopathologic data from the prospective rectal cancer registry and prognosis. End points of the prognostic analysis were tumor progression caused by local and/or distant recurrence and 5-year survival (disease-free and overall). To assess prognostic significance, statistics included univariate and multivariate analysis (p<0.05 statistically significant).

RESULTS

Of the 94 rectal carcinomas, 35% (33/94) showed an epithelial MMP-2 expression, 77% (72/94) were MMP-2 positive in the stroma. Fifty-four percent (51/94) were MMP-7 positive, and 47% (46/94) were positive for both MT1-MMP and TIMP-2. The stromal MMP-2 staining pattern was correlated with the depth of invasion (pT status, p=0.006) with MMP-7 (p=0.016) and TIMP-2 expression (p=0.036). Positive expression of MMP-2 in tumor epithelium was correlated with MMP-7 (p=0.027), MT1-MMP (p=0.036), and TIMP-2 expression (p<0.0001). A positive staining pattern of MMP-7 was significantly correlated with depth of invasion and TIMP-2 (p<0.01). The positive staining pattern of MT1-MMP was correlated with epithelial MMP-2 (p=0.036), MMP-7 (p=0.004), and TIMP-2 expression (p=0.002). TIMP-2 immunoreactivity correlated with depth of invasion (p=0.013), epithelial MMP-2 (p<0.001), stromal MMP-2 (p=0.036), MMP-7 (p<0.001), and MT1-MMP (p=0.002). Neither pattern correlated with age, gender, tumor stage (UICC), grading, preoperative serum carcinoembryonic antigen (CEA) level, or nodal status (p>0.05). Within a mean follow-up of 46 months, tumor progression, caused by either local recurrence or distant metastasis, occurred in 14 patients (15.4%). There was no significant association between the MMP expression and the incidence of local and/or distant recurrence. In terms of survival, preoperative CEA level (disease-free 5-year survival 46% with increased CEA vs 70% with normal CEA, p=0.01; overall 5-year survival 43 vs 74%, p<0.01) and UICC stage were the only factors to be significantly related to 5-year survival by univariate analysis, whereas the metalloproteinases failed to show a significant association. In multivariate analysis, CEA and UICC stage were not identified as independent factors predictive of survival.

CONCLUSION

MMP-2, MMP-7, MT1-MMP, and TIMP-2 do not appear to be significant predictors of prognosis in a homogenous collective of curatively resected rectal adenocarcinomas.

Activity of matrix metalloproteinase-2 (MMP-2) in canine oronasal tumors

Activity of matrix metalloprotease-2 (MMP-2) and the expression of its related molecules were examined in spontaneous canine oronasal tumors. Tissue samples from melanoma and squamous cell carcinoma possessed higher MMP-2 activity, as shown in gelatin zymography, in comparison with acanthomatous epulis and nasal adenocarcinoma. Regional lymph node invasion and distant metastases were more frequently observed in the MMP-2 positive cases. There were no significant differences by RT-PCR examination in the expression of the genes encoding MMP-2, MT1-MMP and TIMP-2 among the tumor histological types. However, the MMP-2/TIMP-2 ratio showed a significantly higher level of the genes in the malignant oral melanoma and squamous cell carcinoma. The MMP-2/TIMP-2 ratio was also positively correlated with MMP-2 activity in gelatin zymography. These results indicate that the MMP-2/TIMP-2 ratio may be of value in evaluating the prognosis in canine oronasal cavity tumors.

Cyclooxygenase-2 expression correlates with membrane-type-1 matrix metalloproteinase expression in colorectal cancer tissue

PURPOSE

Elevated expression of cyclooxygenase-2 has been found in colorectal cancer. One of the mechanisms through which cyclooxygenase-2 affects tumorigenesis is through its overexpression, which leads to increased invasiveness of cancer cells. A crucial step in this pathway is thought to be the induction of membrane-type-1 matrix metalloproteinase, which activates matrix metalloproteinase-2. However, to date there have been few clinicopathologic studies concerning cyclooxygenase-2-mediated invasiveness in human colorectal cancer tissues.

METHODS

We performed immunohistochemical analysis of the respective antigens on colorectal cancer specimens obtained by surgical resections from 96 patients with colorectal cancer.

RESULTS

Cyclooxygenase-2 and membrane-type-1 matrix metalloproteinase expression was positive exclusively in cancer cells in 88 cases (92 percent) and 23 cases (24 percent), respectively. All 23 cases expressing membrane-type-1 matrix metalloproteinase also expressed cyclooxygenase-2. Matrix metalloproteinase-2 expression was positive in cancer cells in 20 cases (21 percent) and stromal cells in 52 cases (54 percent). Expression of matrix metalloproteinase-2 in cancer cells correlated with lymphatic invasion and local recurrence. Statistically, a significant correlation was found between cyclooxygenase-2 and membrane-type-1 matrix metalloproteinase expression, and membrane-type-1 matrix metalloproteinase and matrix metalloproteinase-2 expression in cancer cells. There was no association between cyclooxygenase-2 expression and matrix metalloproteinase-2 expression. However, immunostaining of serial sections revealed that in the majority of cases examined, nearly 100 percent of cancer cells expressing matrix metalloproteinase-2 also coexpressed cyclooxygenase-2.

CONCLUSIONS

This study indicates strong association between both cyclooxygenase-2 and membrane-type-1 matrix metalloproteinase expression, and membrane-type-1 matrix metalloproteinase and matrix metalloproteinase-2 in colorectal cancer. These results support our thesis of a direct correlation between cyclooxygenase-2 and membrane-type-1 matrix metalloproteinase expression--with consequent association between cyclooxygenase-2 and matrix metalloproteinase-2 activation, and tumor invasiveness andrecurrence in certain cases of colorectal cancer.

Modifying the soil to affect the seed: role of stromal-derived matrix metalloproteinases in cancer progression

In the 1980's, as the importance of matrix metalloproteinases (MMPs) in cancer progression was discovered, it was recognized that in most tumors these proteases were abundantly and sometimes exclusively expressed not by tumor cells, but by normal host-derived cells like fibroblasts, vascular endothelial cells, myofibroblasts, pericytes or inflammatory cells that contribute to the tumor microenvironment. Later experiments in mice deficient in specific MMPs revealed that host-derived MMPs play a critical role not only in tumor cell invasion, but also in carcinogenesis, angiogenesis, vasculogenesis and metastasis. Tumor cells secrete many factors, cytokines and chemokines that directly or indirectly increase the expression of these MMPs in the tumor microenvironment where they exert extracellular matrix (ECM) degrading and sheddase activities. The knowledge of the complex role that stromal-derived MMPs play in the interaction between tumor cells and stromal cells should allow us to consider specific windows in cancer treatment when MMP inhibition could have a valuable therapeutic effect.

Simultaneous determination of matrix metalloproteinase (MMP)-7, MMP-1, -3, and -13 gene expression by multiplex PCR in colorectal carcinomas

BACKGROUND AND AIMS

MMP-7, a member of the matrix metalloproteinase family, is believed to play a significant role in the growth and proliferation of colon cancer cells. The aim of this study was to evaluate MMP-7 gene expression in comparison with MMP-1, MMP-3, and MMP-13 in patients with resectable rectal and colon cancer by a semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR).

MATERIALS AND METHODS

Biopsy samples of tumor ( n=30) and distant normal mucosa ( n=30) from 30 patients were obtained intraoperation. Messenger (m)RNA was extracted from all of the tissue samples and reverse transcribed to double-stranded cDNA. Semi-quantitative RT-PCR was performed to study the MMP gene expression in both the tumor and normal mucosal specimens. MMP mRNA values were expressed relative to glyceraldehyde-3-phosphate dehydrogenase (GAPDH) for each sample.

RESULTS

In all 30 cases an increase in MMP-7 mRNA expression was detected in the cancerous tissue ( p=0.00004). In 21 out of 30 cases an increase in MMP-13 mRNA ( p=0.023) and in 22 out of 30 cases an increase in MMP-3 mRNA ( p=0.075) was detected in the cancerous tissue. In contrast, there was no significant change in the MMP-1 expression of normal and cancerous mucosal specimens in either colon or rectal carcinomas. There were no significant differences between rectum and colon carcinomas.

CONCLUSION

Taking into account our earlier studies, we conclude that most cases of colorectal carcinogenesis are characterized by enhanced expression of MMP-7, -13, -3 and the gelatinases, whereas MMP-1-expression is very inconsistent and not overexpressed in many cases. MMP-7 inhibition as well as inhibition of MMP-13 and MMP-3 may be a useful preventive or therapeutic adjunct in colorectal cancer.

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

PURPOSE

Matrix metalloproteinase (MMP)-2 and MMP-9 are considered to play an important role in the metastasis of malignant tumors. Membrane type 1-MMP (MT1-MMP) and tissue inhibitor of metalloproteinase 2 (TIMP-2) are essential factors for the activation of pro-MMP-2. There are some reports about expressions of MMP family in relationship to clinical features of head and neck squamous cell carcinoma (SCC), but the results were not uniform and the prognostic value of their expressions remains unclear.

EXPERIMENTAL DESIGN

The study group consisted of 53 Japanese patients with oral SCC of early stage (T(1-2)N(0)M(0)). Expressions of MMP-2, MMP-9, MT1-MMP, and TIMP-2 were examined using immunohistological methods on the sections of tumor biopsy samples. The intensity of MMP expression was categorized into four grades (score 0-3) by semiquantitative analysis using a computer with NIH image, and correlation between this grade and clinical aspects such as tumor recurrence, metastasis, and prognosis were examined.

RESULTS

The expression score of MMP-2 correlated with that of MMP-9 (r = 0.291; P = 0.036), MT1-MMP (r = 0.286; P = 0.039), and TIMP-2 (r = 0.257; P = 0.050). Patients who developed regional lymph node and/or distant metastasis showed significantly higher scores in the expressions of MMP-9 and TIMP-2 than patients without any tumor metastases (P = 0.036 and P = 0.043, respectively). Kaplan-Meier analyses as well as univariate analyses using the Cox proportional hazards model showed that expression of MMP-9 (P = 0.0143 and P = 0.0418, respectively) and marked expression of TIMP-2 (P < 0.0001 and P = 0.0004, respectively) correlated with worse-cause-specific survival. Multivariate analysis confirmed that marked expression of TIMP-2 was the only independent factor for cause-specific death (hazard ratio, 7.543; confidence interval, 1.693-33.610; P = 0.0080).

CONCLUSIONS

Expressions of MMP-9 and TIMP-2 have predictive value for tumor metastases and cause-specific survival. High expression of TIMP-2 is the most independent factor for worse prognosis in early-stage oral SCC.

Expression and localisation of matrix metalloproteinases and their natural inhibitors in fistulae of patients with Crohn's disease

BACKGROUND

Fistulae are a troublesome complication of Crohn's disease but little is known of the final effector molecules responsible for matrix degradation. Although matrix metalloproteinases (MMPs) have been strongly implicated in tissue injury in Crohn's disease, their role in fistula formation is unknown.

AIM

To determine the expression pattern of MMPs and tissue inhibitors of metalloproteinases (TIMPs) in fistulae of patients with Crohn's disease.

PATIENTS AND METHODS

Resected fistula specimens were obtained from patients with Crohn's disease (n = 11) and classified according to the predominant histological features-that is, acute versus chronic inflammation. Patients with fistulae due to other diseases (n = 9) and normal colon (n = 5) served as controls. MMP and TIMP protein expression was measured by single or double labelled immunohistochemistry, and mRNA expression by in situ hybridisation. MMP activity was measured by gelatin zymography.

RESULTS

Compared with normal colon, strong MMP-3 expression was consistently observed in fistulae in Crohn's disease, irrespective of the stage of inflammatory activity. MMP-3 transcripts and protein were localised in large mononuclear cells and fibroblasts. MMP-9 transcripts and protein were expressed in granulocytes and only in fistulae with acute inflammation. Staining for MMP-1 and MMP-7 was weak and negative for MMP-10, whereas MMP-2 was equally expressed in normal colon and fistulae. TIMP-1, TIMP-2, and TIMP-3 expression was low in all samples. Similar expression patterns were found in fistulae of the disease control group. Fistulae also expressed active MMP-2 and MMP-9, as measured by gelatin zymography.

CONCLUSION

MMP-3 and MMP-9 are markedly upregulated in intestinal fistulae and may contribute to fistula formation through degradation of the extracellular matrix, irrespective of the underlying disease process.

New insights into the roles of matrix metalloproteinases in colorectal cancer development and progression

This review outlines new concepts that are emerging for the functions of matrix metalloproteinases in colorectal cancer development and progression. The two main concepts that will be discussed are the role of matrix metalloproteinases in the early stages of colorectal tumour development and the functional mechanisms by which matrix metalloproteinases contribute to colorectal tumour invasion and metastasis. The matrix metalloproteinases are a group of enzymes, which have been best characterized for their ability to degrade extracellular matrix proteins and thus they have been extensively studied in tumour invasion. It is now becoming recognized that the matrix metalloproteinases have key roles in a variety of biological processes that are distinct from their well-defined role in matrix degradation. This group of enzymes has been shown to interact with a broad range of non-matrix proteins including growth factors and their receptors, mediators of apoptosis, and cell adhesion molecules. The elucidation of novel biological roles for the matrix metalloproteinases also challenges the current predominant concept of matrix metalloproteinases as enzymes only involved in matrix degradation. Recent studies have shown that several matrix metalloproteinases, especially matrilysin (MMP-7), interact with the specific molecular genetic and signalling pathways involved in colorectal cancer development. In particular, matrilysin is activated at an early stage of colorectal tumourigenesis by the beta-catenin signalling pathway. Furthermore, studies are now elucidating specific mechanisms by which individual matrix metalloproteinases, especially membrane-type matrix metalloproteinases, interact with specific cell adhesion molecules and cytoskeletal proteins and thus contribute dynamically to colorectal tumour invasion.

Matrix metalloproteinases 2 and 9 (gelatinases A and B) expression in malignant mesothelioma and benign pleura

Matrix metalloproteinases (MMPs), in particular the gelatinases (MMP-2 and -9), play a significant role in tumour invasion and angiogenesis. The expression and activities of MMPs have not been characterised in malignant mesothelioma (MM) tumour samples. In a prospective study, gelatinase activity was evaluated in homogenised supernatants of snap frozen MM (n=35), inflamed pleura (IP, n=12) and uninflammed pleura (UP, n=14) tissue specimens by semiquantitative gelatin zymography. Matrix metalloproteinases were correlated with clinicopathological factors and with survival using Kaplan-Meier and Cox proportional hazard models. In MM, pro- and active MMP-2 levels were significantly greater than for MMP-9 (P=0.006, P<0.001). Active MMP-2 was significantly greater in MM than in UP (P=0.04). MMP-2 activity was equivalent between IP and MM, but both pro- and active MMP-9 activities were greater in IP (P=0.02, P=0.009). While there were trends towards poor survival with increasing total and pro-MMP-2 activity (P=0.08) in univariate analysis, they were both independent poor prognostic factors in multivariate analysis in conjunction with weight loss (pro-MMP-2 P=0.03, total MMP-2 P=0.04). Total and pro-MMP-2 also contributed to the Cancer and Leukemia Group B prognostic groups. MMP-9 activities were not prognostic. Matrix metalloproteinases, and in particular MMP-2, the most abundant gelatinase, may play an important role in MM tumour growth and metastasis. Agents that reduce MMP synthesis and/or activity may have a role to play in the management of MM.

The plasminogen activator and matrix metalloproteinase systems in colorectal cancer: relationship to tumour pathology

The aim of this study was to determine the expression of proteinases and inhibitors from the matrix metalloproteinase (MMP) (MMPs 1, 2, 3, 9, tissue inhibitors of metalloproteinases (TIMPs) 1, 2) and plasminogen activator ((PA) urokinase (uPA), tissue type (tPA), uPAR, plasminogen activator inhibitors (PAIs) 1, 2) systems in colorectal cancer pathology by gelatin zymography, enzyme-linked immunosorbent assays (ELISAs) and quenched fluorescent substrate hydrolysis. The levels of all studied MMPs, uPA, uPAR, TIMP-1 and PAIs were significantly greater in tumour tissues than normal tissues. However, tPA and TIMP-2 were greater in normal colon (P<0.05, Mann-Whitney) e.g. PAI-1: tumour, median 14.9 (range 0.2-80.2) ng/mg total protein; normal, 2.1 (0.1-65.0). Tumour levels of several factors, in particular MMP-1 and PAI-1, correlated with pathology, i.e. Dukes' stage, differentiation, lymphatic or vascular invasion and tumour depth. The interactions between proteinase systems in colorectal cancer are complex and the balance between active proteinases and their inhibitors is important for extracellular matrix (ECM) degradation/remodelling at each stage of the metastatic cascade.

Nuclear BAG-1 expression reflects malignant potential in colorectal carcinomas

BAG-1 is a recently identified Bcl-2-interacting anti-apoptotic protein. The aim of our study was to investigate the immunohistochemical staining pattern of BAG-1 protein in patients with colorectal cancer and examine associations of BAG-1 expression with various clinicopathological factors and patient survival. Tumour samples were collected from 86 patients diagnosed with colorectal cancer. There was significant variation in the immunohistochemical staining patterns for BAG-1, including absent staining and staining of either the cytoplasm, nucleus or both. Twenty-one colorectal carcinomas (24.4%) exhibited a nuclear staining pattern whilst 56 (65.1%) exhibited cytoplasmic staining. The percentage of cases exhibiting nuclear BAG-1 positivity was significantly higher in distant metastasis-positive cases (55.6%) than in distant metastasis-negative cases (20.8%; P=0.036). Overall survival was significantly shorter for patients with tumours exhibiting BAG-1 positive nuclei than those with absent nuclear BAG-1-staining (P=0.011). In addition, the multivariate cox proportional hazard models indicated that nuclear BAG-1 expression was the only independent prognostic variable for mortality (P=0.013). These studies demonstrate that nuclear BAG-1 expression is a useful predictive factor for distant metastasis and a poor prognosis in patients with colorectal cancer.

Matrix metalloproteinase 13 activity is associated with poor prognosis in colorectal cancer

AIMS

The matrix metalloproteinases (MMPs) are a family of proteolytic enzymes collectively capable of degrading all extracellular matrix components, in particular fibrillar collagen. The importance of this group of proteins in the processes of tumour invasion and metastasis is now widely acknowledged. MMP-13 (collagenase 3) has a central role in the MMP activation cascade. The purpose of this study was to investigate the presence and activity of MMP-13 in colorectal cancer and relate these to clinicopathological features.

METHODS

Immunohistochemistry for MMP-13 was performed on formalin fixed, paraffin wax embedded sections of a large series of colorectal cancers (n = 249), all of which had uniform clinical and pathological information available. Immunoreactivity to MMP-13 was detected with a monoclonal antibody to MMP-13 using a Dako TechMate 500 automated immunostaining system. The presence and cellular localisation of MMP-13 was assessed using a semiquantitative scoring system. Gelatin zymography was used to detect and measure MMP-13 activity. The zymography was performed on a subset of the cases studied by immunohistochemistry using two groups of 10 paired Dukes's C tumours and normal samples, selected by either having "good" or "poor" survival.

RESULTS

Immunoreactivity to MMP-13 was identified in 91% of cases and immunoreactivity was localised to the cytoplasm of tumour cells. A high MMP-13 staining score showed a trend towards poorer survival. Tumours had significantly greater MMP-13 activity compared with normal colonic mucosa (p < 0.001). Furthermore, the tumour to normal tissue ratio was significantly higher in the poor survival group (p = 0.02).

CONCLUSIONS

These results show that MMP-13 is frequently present and active in colorectal cancer and suggest that the activity of MMP-13 is associated with poorer survival in colorectal cancer.

Distribution of collagen type IV alpha1-6 chains in human normal colorectum and colorectal cancer demonstrated by immunofluorescence staining using chain-specific epitope-defined monoclonal antibodies

BACKGROUND AND AIM

Loss of basement membrane (BM) components, such as type IV collagen, has been demonstrated in colorectal cancer, but the fine diversity of the assembly of alpha (IV) chains, the composition of type IV collagen, and alterations in the collagen have not been fully analyzed. Here, we defined immunohistochemically the expression of alpha1-6 (IV) chains in colorectal cancer tissues and adjacent normal mucosa by the use of chain-specific monoclonal antibodies.

METHODS

Tissue samples of tumor and adjacent normal mucosa obtained from patients with colorectal adenocarcinoma were stained with chain-specific monoclonal antibodies raised against synthetic peptides of individual alpha (IV) chains using an indirect immunofluorescence method.

RESULTS

In the normal mucosa, alpha1 (IV), alpha2 (IV), alpha5 (IV), and alpha6 (IV) were found in the BM-delineating mucosal epithelium and the gland crypts, whereas alpha3 (IV) and alpha4 (IV) were limited to the BM of the luminal surface epithelium. In contrast, staining of alpha3-6 (IV) was rarely observed in the BM of cancer cells. Staining of alpha1 (IV) and alpha2 (IV) was reduced or lost from the cancer BM in relation to the degree of tumor differentiation: continuous staining in well-differentiated portions, discontinuous staining in moderately differentiated portions, and absence of staining in poorly differentiated portions.

CONCLUSIONS

Our findings indicate that type IV collagen expression is altered in the BM of colorectal cancer as a result of changes of alpha (IV) chain expression, particularly alpha1 (IV) and alpha2 (IV), in relation to the degree of tumor differentiation.

Tissue levels of active matrix metalloproteinase-2 and -9 in colorectal cancer

The bioactivity of matrix metalloproteinases was studied in tissues from colorectal cancer patients by means of both quantitative gelatin zymography and a fluorometric activity assay. Next to paired samples of tumour tissue and distant normal mucosa (n=73), transitional tissue was analysed from a limited (n=33) number of patients. Broad-spectrum matrix metalloproteinase activity and both the active and latent forms of the gelatinases matrix metalloproteinase-2 and -9 were higher in tumour than in normal mucosa. The ratio's between active and latent forms of matrix metalloproteinase-2 and -9 were highest in tumour tissue and normal mucosa, respectively. Matrix metalloproteinase-2 levels, both active and latent forms, correlated inversely with stage of disease, the tumours without synchronous distant metastases containing significantly (P=0.005) more active matrix metalloproteinase-2 than the others. At much lower levels of activity, the same trend was observed in distant normal mucosa. The level of latent form of matrix metalloproteinase-9 in tumour depended on tumour location. Neither the active form of matrix metalloproteinase-9 nor broad-spectrum matrix metalloproteinase activity in tumour tissue did correlate with any of the clinicopathological parameters investigated. The results demonstrate explicit differences between the activity of matrix metalloproteinase-2 and -9, indicating different roles for both gelatinases in tumour progression. Such data are necessary in order to develop rational anti-cancer therapies based on inhibition of specific matrix metalloproteinases.

Utility of MMP-1, p53, E-cadherin, and collagen IV immunohistochemical stains in the differential diagnosis of adenomas with misplaced epithelium versus adenomas with invasive adenocarcinoma

Adenomas with misplaced epithelium in the submucosa of the polyp stalk ("pseudoinvasion") may be difficult to distinguish from adenomas that harbor invasive adenocarcinoma by morphologic analysis. Recently, several epithelial and stromal proteins, such as matrix metalloproteinase-1 (MMP-1), p53, E-cadherin, and collagen IV, have been shown to be altered in colonic adenocarcinomas in comparison with adenomas and normal colonic mucosa. Therefore, the purpose of this study was to evaluate the diagnostic use of several epithelial (p53, E-cadherin) and stromal (MMP-1, collagen IV) markers in distinguishing adenomas with misplaced epithelium from those with invasive adenocarcinoma. Routinely processed polypectomy specimens from 23 patients with an adenoma with misplaced epithelium (male/female ratio 12/11; mean age 65 years) and 23 patients with an adenocarcinoma arising in an adenoma (male/female ratio 13/10; mean age 63 years) were immunohistochemically stained (avidin-biotin complex method) for monoclonal antibodies to MMP-1 (epithelial and stromal cell collagenase), p53 (tumor suppression gene), E-cadherin (intercellular adhesion protein), and collagen IV (basement membrane collagen component), and the results were compared between the two polyp groups. Where appropriate, immunopositivity was evaluated in the epithelium (MMP-1, p53, E-cadherin), stroma (MMP-1), and/or basement membrane (collagen IV). Cases were considered positive if an increase (MMP-1, p53) or decrease (E-cadherin, collagen IV) in either the intensity or proportion of cells staining was noted in the submucosal epithelial component compared with the intramucosal portion of the polyp head for each individual polyp. In adenomas with invasive adenocarcinoma, MMP-1 staining of the stroma surrounding submucosal epithelium and p53 nuclear staining within the epithelium were increased in 21 (91%) and 14 (61%) cases, respectively, whereas decreased or discontinuous E-cadherin and collagen IV staining was noted in 15 (65%) and 22 (96%) cases, respectively. All these values were significantly different (p < 0.005) from those observed in adenomas with misplaced epithelium [MMP-1, 11 of 23 (48%); p53, 1 of 23 (4%); E-cadherin, 0 of 23 (0%); collagen IV, 0/23 (0%)]. Furthermore, in three diagnostically difficult cases that contained foci of misplaced epithelium with high-grade dysplasia, the immunohistochemical results confirmed the impression that the lesions represented epithelial misplacement rather than invasive adenocarcinoma. In conclusion, the degree and/or pattern of MMP-1, p53, E-cadherin, and collagen IV staining in the submucosal epithelial elements in comparison with the intramucosal adenomatous tissue may help distinguish adenomas with misplaced epithelium from those with invasive adenocarcinoma.

Matrix metalloproteinases in colorectal cancer

Matrix metalloproteinases (MMPs) appear to play a key role in the development and progression of human malignancies. MMPs mediate the destruction of the extracellular matrix, which is an important early step in tumor invasion and metastasis. Growing evidence suggests that MMPs also have angiogenic activity and participate in the early stages of tumorigenesis and primary tumor growth. Investigations in experimental animal models have confirmed the importance of MMPs in the pathogenesis of colorectal cancer, and studies in humans show a direct association between increased MMP expression and tumor invasiveness, development of metastases, and shortened survival. In this review, the physiologic role of MMPs in normal tissues is examined and data supporting the role of MMPs in the pathogenesis of colorectal cancer are reviewed. The results of clinical trials with MMP inhibitors in colorectal cancer and promising areas for future investigation are also discussed.

Measuring gelatinase activity in colorectal cancer

AIMS

Gelatinases (MMP-2, -9) are the most extensively studied MMPs in cancer. The aim of the study was to determine the levels of active and latent forms of the gelatinases in paired colorectal tumour and normal tissue ( n=77) and correlate these with pathological stage.

METHODS

Gelatinase levels were compared following the techniques of gelatin zymography (active and latent) and the novel gelatinase activity assays (total and endogenous/active).

RESULTS

Both latent and active MMP-2 and MMP-9 lysis bands (zymography) and both total (active and latent) MMP-9 and endogenous (active) MMP-9 and MMP-2 levels (activity assays) were greater in tumour than normal colorectal tissue. Total MMP-2 and MMP-9 levels as determined by activity assays correlated with both the Dukes staging (e.g. total MMP-9 in tumours: adenoma, 1.0 (0.3--3.6); Dukes A, 9.6 (2.4--35.4); Dukes B, 14.7 (1.5--103.9); Dukes C, 22.3 (2.2--57.9) and Dukes D, 37.4 (2.1--47.0) ng/mg protein) and with lymphatic invasion (e.g. total MMP-9; in tumours which had undergone lymphatic invasion, 22.7 (2.1--57.9) and those with no lymphatic invasion, 14.0 (1.5--103.9) ng/mg protein).

CONCLUSIONS

Both gelatinases were upregulated in tumour tissue, however total and not endogenous active levels correlated with the pathological stage of the tumour. Therefore gelatinases may only be activated when required for tumour invasion and metastasis.