The Immunoexpression of Heparanase 2 in Normal Epithelium, Intraepithelial, and Invasive Squamous Neoplasia of the Cervix

Alterations of the Extracellular Matrix in Colorectal Carcinoma

Background: The process of proliferation and invasion of tumor cells depends on changes in the extracellular matrix (ECM) through the activation of enzymes and alterations in the profile of ECM components. Our aims are to investigate the mRNA and protein expression profiles of the ECM components, heparanase-1 (HPSE), heparanase-2 (HPSE2), matrix metalloproteinase-9 (MMP-9), and syndecan-1 (SDC1) in neoplastic and nonneoplastic tissues of 24 patients with colorectal carcinoma (CRC) and to test for associations between these expression patterns with the presence or absence of lymph node metastasis. Materials and Methods: This was a cross-sectional study in which 24 adult patients with CRC were admitted for resectional surgery. We analyzed the mRNA and protein expression patterns of the HPSE, HPSE2, MMP-9, and SDC1 genes by quantitative reverse transcription PCR and immunohistochemistry, respectively. Additionally, we investigated whether variations exist in the expression of the ECM components between the affected tissue and nontumoral tissue collected from the same patient. Tissue samples were collected immediately after the surgical resection. Results and Conclusion: The data showed higher mRNA and protein expression levels of HPSE2 (p = 0.0058), MMP-9 (p = 0.0268), and SDC1 (p = 0.0002) in tumor samples when compared with the nonneoplastic tissues. There was, however, only an increase in the level of the HPSE protein in the tumoral tissues. Increased expression of HPSE2 was observed in patients with lymph node metastasis (p = 0.031). This elevation in HPSE2 mRNA expression in patients with lymph node metastasis potentially indicates that it may participate in driving colorectal carcinoma progression.

Hypermethylation of heparanase 2 promotes colorectal cancer proliferation and is associated with poor prognosis

BACKGROUND

The epigenetic abnormality of tumor-associated genes contributes to the pathogenesis of colorectal carcinoma (CRC). However, methylation in colorectal cancer is still poorly characterized.

METHOD

By integration of DNA methylation data from the GEO database and gene expression data from The Cancer Genome Atlas database, the aberrantly methylated genes involved in CRC tumorigenesis were identified. Subsequent in vitro experiments further validated their role in CRC.

RESULTS

We performed integrative genomic analysis and identified HPSE2, a novel tumor suppressor gene that is frequently inactivated through promoter methylation in CRC. K-M survival analysis showed that hypermethylation-low expression of heparanase 2 (HPSE2) was related to poor patient prognosis. Overexpression of HPSE2 reduced cell proliferation in vivo and in vitro. HPSE2 could regulate the p53 signaling pathway to block the cell cycle in G1 phase.

CONCLUSION

HPSE2, a novel tumor suppressor gene that is frequently inactivated through promoter methylation in CRC. HPSE2 performs a tumor suppressive function by activating the p53/ p21 signaling cascade. The promoter hypermethylation of HPSE2 is a potential therapeutic target in patients with CRC, especially those with late-stage CRC.

The Good and Bad Sides of Heparanase-1 and Heparanase-2

In this chapter, we will emphasize the importance of heparan sulfate proteoglycans (HSPG) in controlling various physiological and pathological molecular mechanisms and discuss how the heparanase enzyme can modulate the effects triggered by HSPG. Additionally, we will also navigate about the existing knowledge of the possible role of heparanase-2 in biological events. Heparan sulfate is widely distributed and evolutionarily conserved, evidencing its vital importance in cell development and functions such as cell proliferation, migration, adhesion, differentiation, and angiogenesis. During remodeling of the extracellular matrix, the breakdown of heparan sulfate by heparanase results in the release of molecules containing anchored glycosaminoglycan chains of great interest in heparanase-mediated cell signaling pathways in various physiological states, tumor development, inflammation, and other diseases. Taken together, it appears that heparanase plays a key role in the maintenance of the pathology of cancer and inflammatory diseases and is a potential target for anti-cancer therapies. Therefore, heparanase inhibitors are currently being examined in clinical trials as novel cancer therapeutics. Heparanase-2 has no enzymatic activity, displays higher affinity for heparan sulfate and the coding region alignment shows 40% identity with the heparanase gene. Heparanase-2 plays an important role in embryogenic development however its mode of action and biological function remain to be elucidated. Heparanase-2 functions as an inhibitor of the heparanase-1 enzyme and also inhibits neovascularization mediated by VEGF. The HPSE2 gene is repressed by the Polycomb complex, together suggesting a role as a tumor suppressor.

Heparanase: A Challenging Cancer Drug Target

Heparanase has been viewed as a promising anti-cancer drug target for almost two decades, but no anti-heparanase therapy has yet reached the clinic. This endoglycosidase is highly expressed in a variety of malignancies, and its high expression is associated with greater tumor size, more metastases, and a poor prognosis. It was first described as an enzyme cleaving heparan sulfate chains of proteoglycans located in extracellular matrices and on cell surfaces, but this is not its only function. It is a multi-functional protein with activities that are enzymatic and non-enzymatic and which take place both outside of the cell and intracellularly. Knowledge of the crystal structure of heparanase has assisted the interpretation of earlier structure-function studies as well as in the design of potential anti-heparanase agents. This review re-examines the various functions of heparanase in light of the structural data. The functions of the heparanase variant, T5, and structure and functions of heparanase-2 are also examined as these heparanase related, but non-enzymatic, proteins are likely to influence the in vivo efficacy of anti-heparanase drugs. The anti-heparanase drugs currently under development predominately focus on inhibiting the enzymatic activity of heparanase, which, in the absence of inhibitors with high clinical efficacy, prompts a discussion of whether this is the best approach. The diversity of outcomes attributed to heparanase and the difficulties of unequivocally determining which of these are due to its enzymatic activity is also discussed and leads us to the conclusion that heparanase is a valid, but challenging drug target for cancer.

Common cancer in a wild animal: the California sea lion (Zalophus californianus) as an emerging model for carcinogenesis

Naturally occurring cancers in non-laboratory species have great potential in helping to decipher the often complex causes of neoplasia. Wild animal models could add substantially to our understanding of carcinogenesis, particularly of genetic and environmental interactions, but they are currently underutilized. Studying neoplasia in wild animals is difficult and especially challenging in marine mammals owing to their inaccessibility, lack of exposure history, and ethical, logistical and legal limits on experimentation. Despite this, California sea lions (Zalophus californianus) offer an opportunity to investigate risk factors for neoplasia development that have implications for terrestrial mammals and humans who share much of their environment and diet. A relatively accessible California sea lion population on the west coast of the USA has a high prevalence of urogenital carcinoma and is regularly sampled during veterinary care in wildlife rehabilitation centres. Collaborative studies have revealed that genotype, persistent organic pollutants and a herpesvirus are all associated with this cancer. This paper reviews research to date on the epidemiology and pathogenesis of urogenital carcinoma in this species, and presents the California sea lion as an important and currently underexploited wild animal model of carcinogenesis.

The Profile of Heparanase Expression Distinguishes Differentiated Thyroid Carcinoma from Benign Neoplasms

Introduction

The search for a specific marker that could help to distinguish between differentiated thyroid carcinoma and benign lesions remains elusive in clinical practice. Heparanase (HPSE) is an endo-beta-glucoronidase implicated in the process of tumor invasion, and the heparanase-2 (HPSE2) modulates HPSE activity. The aim of this study was to evaluate the role of heparanases in the development and differential diagnosis of follicular pattern thyroid lesions.

Methods

HPSE and HPSE2 expression by qRT-PCR, immunohistochemistry evaluation, western blot analysis and HPSE enzymatic activity were evaluated.

Results

The expression of heparanases by qRT-PCR showed an increase of HPSE2 in thyroid carcinoma (P = 0.001). HPSE activity was found to be higher in the malignant neoplasms than in the benign tumors (P<0.0001). On Western blot analysis, HPSE2 isoforms were detected only in malignant tumors. The immunohistochemical assay allowed us to establish a distinct pattern for malignant and benign tumors. Carcinomas showed a typical combination of positive labeling for neoplastic cells and negative immunostaining in colloid, when compared to benign tumors (P<0.0001). The proposed diagnostic test presents sensitivity and negative predictive value of around 100%, showing itself to be an accurate test for distinguishing between malignant and benign lesions.

Conclusions

This study shows, for the first time, a distinct profile of HPSE expression in thyroid carcinoma suggesting its role in carcinogenesis.

Immunohistochemical Expression of Heparanases 1 and 2 in Benign Tissue and in Invasive Neoplasia of the Endometrium: A Case-Control Study

Objectives

Our purpose was to compare the expression of heparanase isoforms, in normal and in neoplastic endometrium. In a pioneering way, we sought to evaluate the expression of heparanase 1 (HPSE1) and heparanase 2 (HPSE2) in glandular and in stromal tissues.

Methods

This is a case-control study, conducted retrospectively in a public hospital, using paraffin blocks of endometrial tissue from patients admitted from 2002 to 2011 with and without endometrial cancer, with regard to the immunohistochemical expression of HPSE1 and HPSE2. The paraffin blocks were used for tissue microarray analysis and immunohistochemistry study in glandular and stromal tissues.

Results

In the study period, 195 participants were enrolled, 75 with and 120 without cancer. There was no significant difference between them regarding HPSE1 expression, both in gland and in stromal tissues. Heparanase 1 expression in the glandular tissue was more frequent among those with high-grade carcinoma, compared with patients with carcinoma type I. The difference in the expression of HPSE2 was significant between groups: it was less frequent in the controls than in the patients with cancer in the glandular tissue. In the stromal tissue, HPSE2 expression was significantly higher in the controls than in the patients with cancer and different when patients of the secretory endometrium subgroup were compared with those with hypotrophic, proliferative endometriums or with architectural disorders. No significant difference was found in the heparanase expressions in patients with cancer according to prognosis factors.

Conclusions

Heparanase 1 is more intensely expressed in the glandular tissue of high-grade compared with type I carcinomas. Heparanase 2 is more intensely expressed in the glandular tissue of cancer than in nonneoplastic endometrium, whereas the HPSE2 expression in the stromal tissue is higher in the nonneoplastic controls compared with the group of patients with cancer mainly in the secretory endometrium. This suggests that HPSE2 might be stimulated by progesterone, with a possible antineoplastic role, antagonist to HPSE1, to be further investigated.

Analysis of heparanase isoforms and cathepsin B in the plasma of patients with gastrointestinal carcinomas: analytical cross-sectional study

CONTEXT AND OBJECTIVE

Heparanase-1 degrades heparan sulfate and has been correlated with tumor progression. Although the isoform heparanase-2 has no catalytic activity, it seems to be important for modulating heparanase-1 activity. Cathepsin B is a proteinase involved in tumor metastasis. The aim of this study was to analyze heparanase isoform expression and cathepsin B activity in plasma samples from patients with gastrointestinal carcinomas, compared with healthy individuals (control group).

DESIGN AND SETTING

This was an analytical cross-sectional study. Peripheral blood samples were collected at a Brazilian public hospital, from 21 patients with histopathological diagnoses of gastrointestinal carcinomas and from 43 healthy individuals. The analyses were performed in two Brazilian medical schools.

METHODS

Heparanase isoforms were identified and quantified in plasma samples by means of Western blot. The enzymatic activities of heparanase-1 and cathepsin B were also measured.

RESULTS

The results demonstrated that the expression of both heparanase isoforms was significantly greater in plasma samples from gastrointestinal carcinoma patients, compared with the control group. Logistic regression analysis showed that increased heparanase-1 and heparanase-2 expression was exclusively dependent on the tumor. There was a significant increase in heparanase-1 and cathepsin B activity in the patients' plasma.

CONCLUSION

Overexpression of heparanase-1 and heparanase-2, along with increased heparanase-1 and cathepsin B activity in plasma, is associated with the diagnosis of gastrointestinal carcinoma. These findings provide support for using non-invasive assays (plasma samples) as an auxiliary method for diagnosing gastrointestinal tumors.

High expression of heparanase-2 is an independent prognostic parameter for favorable survival in gastric cancer patients

AIM

Heparanase-2 expression has been suggested to up-regulate in several types of human cancers. However, the expression patterns of heparanase-2 in gastric cancer and its effect on prognosis of gastric cancer patients are unclear.

METHODS

In this study, the methods of tissue microarray, immunohistochemistry (IHC), and western blot were used to investigate heparanase-2 expression in gastric cancer and the adjacent non-cancerous tissues. Heparanase-2 expression was analyzed by immunohistochemistry in 95 clinicopathologically characterized gastric cancer cases. In addition Fisher's exact test, Kaplan-Meier plots and Cox proportional hazards regression model were used to analyze the results.

RESULTS

High expression of cytoplasmic heparanase-2 was observed in 70.5% (67/95) of gastric cancer, when compared with its normal counterpart. Overexpression of heparanase-2 was correlated with tumor size and differentiation (P<0.05). Further analysis showed that a significant correlation between high expression of heparanase-2 and favorable prognosis (P<0.05). In multivariate analysis, high expression of heparanase-2 was evaluated as an independent prognostic factor in gastric cancer (P<0.05).

CONCLUSIONS

Our data suggest for the first time that the high expression of heparanase-2 is associated significantly with tumor growth and differentiation. Importantly, heparanase-2 may be a potential molecular marker for predicting prognosis of gastric cancer.