Molecular and cellular basis of cancer invasion and metastasis: implications for treatment

Exploring risk factors and molecular targets in leukemia patients with COVID-19: a bioinformatics analysis of differential gene expression

The molecular mechanism of COVID-19's pathogenic effects in leukemia patients is still poorly known. Our study investigated the possible disease mechanism of COVID-19 and its associated risk factors in patients with leukemia utilizing differential gene expression analysis. We also employed network-based approaches to identify molecular targets that could potentially diagnose and treat COVID-19-infected leukemia patients. Our study demonstrated a shared set of 60 genes that are expressed differentially among patients with leukemia and COVID-19. Most of these genes are expressed in blood and bone marrow tissues and are predominantly implicated in the pathogenesis of different hematologic malignancies, increasingly imperiling COVID-19 morbidity and mortality among the affected patients. Additionally, we also found that COVID-19 may influence the expression of several cancer-associated genes in leukemia patients, such as CCR7, LEF1, and 13 candidate cancer-driver genes. Furthermore, our findings reveal that COVID-19 may predispose leukemia patients to altered blood homeostasis, increase the risk of COVID-19-related liver injury, and deteriorate leukemia-associated injury and patient prognosis. Our findings imply that molecular signatures, like transcription factors, proteins such as TOP21, and 25 different microRNAs, may be potential targets for diagnosing and treating COVID-19-infected leukemia patients. Nevertheless, additional experimental studies will contribute to further validating the study's findings.

Molecular dynamics simulation study on the structures of fascin mutants

Fascin is a filamentous actin (F-actin) bundling protein, which cross-links F-actin into bundles and becomes an important component of filopodia on the cell surface. Fascin is overexpressed in many types of cancers. The mutation of fascin affects its ability to bind to F-actin and the progress of cancer. In this paper, we have studied the effects of residues of K22, K41, K43, K241, K358, K399, and K471 using molecular dynamics (MD) simulation. For the strong-effect residues, that is, K22, K41, K43, K358, and K471, our results show that the mutation of K to A leads to large values of root mean square fluctuation (RMSF) around the mutated residues, indicating those residues are important for the flexibility and thermal stability. On the other hand, based on residue cross-correlation analysis, alanine mutations of these residues reinforce the correlation between residues. Together with the RMSF data, the local flexibility is extended to the entire protein by the strong correlations to influence the dynamics and function of fascin. By contrast, for the mutants of K241A and K399A those do not affect the function of fascin, the RMSF data do not show significant differences compared with wild-type fascin. These findings are in a good agreement with experimental studies.

Preventive and therapeutic effect of intraportal oridonin on BALb/c nude mice hemispleen model of colon cancer liver metastasis

Background

This study is to investigate the preventive and therapeutic effect of intraportal oridonin on colorectal cancer liver metastasis (CRCLM).

Methods

The inhibitory effect of oridonin on HT29 cells was determined by CCK-8 and MTT assays. The preventive and therapeutic effect of intraportal oridonin on CRCLM were investigated by establishing BALb/c nude mice hemispleen models of colon cancer liver metastasis. The microscopic characteristics of tumor tissues were observed by hematoxylin-eosin staining, immunohistochemistry and TUNEL staining. On the other hand, liver function enzymes, such as alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP), were detected to evaluate the hepatotoxicity of intraportal oridonin. The serum levels of tumor markers, including carcinoembryonic antigen (CEA) and α-fetoprotein (AFP), were used to investigate the intervention effect of intraportal oridonin on CRCLM.

Results

Oridonin exerted an inhibitory effect on the proliferation of HT29 cells in vitro. Intraportal oridonin was found to effectively prevent the occurrence and formation of CRCLM, whilst intraportal oridonin can also exert a therapeutic effect on CRCLM. Additionally, liver enzymes testing indicated that intraportal oridonin possesses non-hepatotoxicity, instead can effectively alleviate liver injury caused by tumor. Furthermore, intraportal oridonin was also revealed to decrease the serum levels of AFP and CEA.

Conclusions

Intraportal oridonin can effectively inhibit the formation of liver metastatic tumor and exert a certain degree of preventive and therapeutic effect on CRCLM. These findings indicate intraportal oridonin to be a promising anti-metastasis agent for CRCLM.

Local Delivery and Glioblastoma: Why Not Combining Sustained Release and Targeting?

Glioblastoma is one of the most aggressive brain tumors and is associated with a very low overall median survival despite the current treatment. The standard of care used in clinic is the Stupp's protocol which consists of a maximal resection of the tumor when possible, followed by radio and chemotherapy using temozolomide. However, in most cases, glioblastoma cells infiltrate healthy tissues and lead to fatal recurrences. There are a lot of hurdles to overcome in the development of new therapeutic strategies such as tumor heterogeneity, cell infiltration, alkylating agent resistance, physiological barriers, etc., and few treatments are on the market today. One of them is particularly appealing because it is a local therapy, which does not bring additional invasiveness since tumor resection is included in the gold standard treatment. They are implants: the Gliadel^® wafers, which are deposited post-surgery. Nevertheless, in addition to presenting important undesirable effects, it does not bring any major benefit in the therapy despite the strategy being particularly attractive. The purpose of this review is to provide an overview of recent advances in the development of innovative therapeutic strategies for glioblastoma using an implant-type approach. The combination of this local strategy with effective targeting of the tumor microenvironment as a whole, also developed in this review, may be of interest to alleviate some of the obstacles encountered in the treatment of glioblastoma.

TMPRSS4 overexpression promotes the metastasis of colorectal cancer and predicts poor prognosis of stage III-IV colorectal cancer

PURPOSE

To study in detail the expression pattern and prognostic significance of TMPRSS4 in colorectal cancer.

METHODS

The expression of TMPRSS4 protein was determined using Western blot in the colorectal cancer tissues and normal tissues. Immunohistochemistry was used to detect the TMPRSS4 expression in colorectal cancer tissues, and the clinicopathologic characteristics and prognostic significance were analyzed.

RESULTS

TMPRSS4 overexpression was associated with tumor budding, lymphovascular invasion, perineural invasion, cancerous emboli, infiltration depth, lymph node metastasis, distant metastasis, and tumor node metastasis stage (P < 0.05 for all). Interestingly, TMPRSS4 expression in the tumor budding, tumor emboli, lymph node, and liver metastatic tumor samples was higher than in the paired primary tumors. In contrast, TMPRSS4 overexpression is inversely correlated with both the overall survival and the disease-free survival of the patients with colorectal cancer (P < 0.05 for both). Also, we found that TMPRSS4 is only of significance in predicting the prognosis of stage III and IV colorectal cancer, not stage I and II.

CONCLUSIONS

TMPRSS4 was shown to be involved in the whole process of metastasis from tumor budding to lymph node and/or distant metastasis in colorectal cancer and predicted the unfavorable prognosis of stage III-IV, indicating that it is a novel target for the precise treatment of colorectal cancer with lymph node or distant organ metastasis.

Neuroimmune Regulation of Surgery-Associated Metastases

Surgery remains an essential therapeutic approach for most solid malignancies. Although for more than a century accumulating clinical and experimental data have indicated that surgical procedures themselves may promote the appearance and progression of recurrent and metastatic lesions, only in recent years has renewed interest been taken in the mechanism by which metastasizing of cancer occurs following operative procedures. It is well proven now that surgery constitutes a risk factor for the promotion of pre-existing, possibly dormant micrometastases and the acceleration of new metastases through several mechanisms, including the release of neuroendocrine and stress hormones and wound healing pathway-associated immunosuppression, neovascularization, and tissue remodeling. These postoperative consequences synergistically facilitate the establishment of new metastases and the development of pre-existing micrometastases. While only in recent years the role of the peripheral nervous system has been recognized as another contributor to cancer development and metastasis, little is known about the contribution of tumor-associated neuronal and neuroglial elements in the metastatic disease related to surgical trauma and wound healing. Specifically, although numerous clinical and experimental data suggest that biopsy- and surgery-induced wound healing can promote survival and metastatic spread of residual and dormant malignant cells, the involvement of the tumor-associated neuroglial cells in the formation of metastases following tissue injury has not been well understood. Understanding the clinical significance and underlying mechanisms of neuroimmune regulation of surgery-associated metastasis will not only advance the field of neuro–immuno–oncology and contribute to basic science and translational oncology research but will also produce a strong foundation for developing novel mechanism-based therapeutic approaches that may protect patients against the oncologically adverse effects of primary tumor biopsy and excision.

Aberrant ETS-1 signalling impedes the expression of cell adhesion molecules and matrix metalloproteinases in non-segmental vitiligo

Cell adhesion is a complex process that involves multiple molecules on the cell surface (ie cell adhesion molecules [CAMs]), surrounding cells and extracellular matrix (ECM). Repigmentation in vitiligo is dependent on the ECM remodelling and cellular migration, primarily attributed to the transcriptional activation of matrix metalloproteinases (MMPs). In this study, we aimed to demonstrate the role of ETS-1 signalling in the regulation of MMPs and CAMs. Therefore, we studied the expression of ETS-1, MMPs (MMP-2, MMP-9) and CAMs including E-cadherin, ITGA-1 and ICAM-1 in vitiligo (both active and stable) ex vivo. Further, we compared melanocyte morphology and their adhesion towards collagen IV and laminin between control and vitiligo groups in vitro. Also, we silenced ETS-1 in melanocytes cultured from control skin and observed post-silencing effect on above-mentioned MMPs and CAMs. We perceived absent ETS-1 and significantly reduced CAMs and MMPs in vitiligo compared with normal skin. Scanning electron microscopy (SEM) revealed a translucent material surrounding individual melanocytes in stable vitiligo and controls, whereas active vitiligo melanocytes demonstrated loss of this extracellular substance. Adhesion assays revealed significantly decreased binding of cultured melanocytes to collagen IV and laminin V plates in both stable and active vitiligo. Importantly, ETS-1 silencing resulted in significantly reduced expression of CAMs and MMPs. In conclusion, absent ETS-1 expression in both stable and active non-segmental vitiligo seems to impede the expression of CAMs, apart from MMPs, probably leading to progressive depigmentation in active disease and absence of spontaneous repigmentation in stable disease.

Claudin-1 upregulation is associated with favorable tumor features and a reduced risk for biochemical recurrence in ERG-positive prostate cancer

BACKGROUND

Claudin-1 is a membrane-tight junction protein and important for the sealing of the paracellular cleft in epithelial and endothelial cells. Differential expression of Claudin-1 is linked to disease outcome in various cancers.

MATERIAL AND METHODS

To evaluate the potential relevance of Claudin-1 expression in prostate cancer, a tissue microarray containing samples of 17,747 tumors with annotated clinico-pathological and molecular data was immunohistochemically analyzed for Claudin-1 expression.

RESULTS

In normal prostate, glandular cells were always Claudin-1-negative while there was a strong staining of gland-surrounding basal cells. In contrast to normal prostatic glands, a positive Claudin-1 immunostaining, was found, however, in 38.7% of 12,441 interpretable cancers and was considered weak in 12.7%, moderate in 13.2%, and strong in 12.8% of cases. Positive Claudin-1 immunostaining was associated with favorable tumor features like low pT (p = 0.0032), low Gleason grade (p< 0.0001), and a reduced risk of PSA recurrence (p = 0.0005). A positive Claudin-1 staining was markedly more frequent in ERG-positive (63%) than in ERG-negative cancers (23%; p < 0.0001). Subset analyses revealed that all associations of Claudin-1 expression and favorable phenotype and prognosis were driven by ERG-positive cancers. Multivariate analyses revealed, however, that even in ERG-positive cancers, the prognostic impact of high Claudin-1 expression was not independent of established clinico-pathological parameters. Comparison with 12 previously analyzed chromosomal deletions identified conspicuous associations with PTEN and 12p13 deletions potentially indicating functional interactions.

CONCLUSION

These data identify a peculiar role for Claudin-1 in prostate cancer. The protein is overexpressed in a fraction of prostate cancers and increased Claudin-1 expression levels predict a favorable prognosis in ERG-positive cancer.

Matrix Hyaluronan-CD44 Interaction Activates MicroRNA and LncRNA Signaling Associated With Chemoresistance, Invasion, and Tumor Progression

Tumor malignancies involve cancer cell growth, issue invasion, metastasis and often drug resistance. A great deal of effort has been placed on searching for unique molecule(s) overexpressed in cancer cells that correlate(s) with tumor cell-specific behaviors. Hyaluronan (HA), one of the major ECM (extracellular matrix) components have been identified as a physiological ligand for surface CD44 isoforms which are frequently overexpressed in malignant tumor cells during cancer progression. The binding interaction between HA and CD44 isoforms often stimulates aberrant cellular signaling processes and appears to be responsible for the induction of multiple oncogenic events required for cancer-specific phenotypes and behaviors. In recent years, both microRNAs (miRNAs) (with ~20–25 nucleotides) and long non-coding RNAs (lncRNAs) (with ~200 nucleotides) have been found to be abnormally expressed in cancer cells and actively participate in numerous oncogenic signaling events needed for tumor cell-specific functions. In this review, I plan to place a special emphasis on HA/CD44-induced signaling pathways and the presence of several novel miRNAs (e.g., miR-10b/miR-302/miR-21) and lncRNAs (e.g., UCA1) together with their target functions (e.g., tumor cell migration, invasion, and chemoresistance) during cancer development and progression. I believe that important information can be obtained from these studies on HA/CD44-activated miRNAs and lncRNA that may be very valuable for the future development of innovative therapeutic drugs for the treatment of matrix HA/CD44-mediated cancers.

CD44v10: An Antimetastatic Membrane Glycoprotein for Pancreatic Cancer

Aims

The aims of this study were 1) to investigate the mRNA pattern of CD44 variants in three primary (MIA PaCa 2, PANC-1, PSN-1) and two metastatic (CAPAN-1, SUIT-2) pancreatic cancer (PC) cell lines; 2) to ascertain whether the genetic transfer of CD44s and CD44v10 modifies the adhesion of PC cells to the extracellular matrix (ECM) in vitro and their metastatic behavior in vivo.

Methods

CD44 mRNA analysis was done by means of RT-PCR. Adhesion to ECM the was assessed using coated microtiter plates. For the study of CD44v10 insertion in the CAPAN-1 line, liposome-mediated DNA transfer was used. SCID mice were employed for in vivo experiments.

Results

CD44v10 mRNA was not expressed by the CAPAN-1 nor by four of the six SUIT-2-derived clones. The stable expression of CD44v10 by modified CAPAN-1 significantly enhanced fibronectin adhesion. Mice without either liver or pancreatic metastases were more frequently found among the animals injected with modified (CD44v10 expressing) than with non-modified CAPAN-1.

Conclusions

1) It is possible to differentiate between metastatic and non-metastatic PC cells on the basis of CD44v10 expression; 2) CD44v10 seems to be involved in mediating fibronectin adhesion in vitro and in counteracting metastases in vivo.

Activation of Matrix Hyaluronan-Mediated CD44 Signaling, Epigenetic Regulation and Chemoresistance in Head and Neck Cancer Stem Cells

Head and neck squamous cell carcinoma (HNSCC) is a solid tumor composed by a genotypically and phenotypically heterogeneous population of neoplastic cells types. High recurrence rate and regional metastases lead to major morbidity and mortality. Recently, many studies have focused on cellular and molecular mechanisms of tumor progression that can help to predict prognosis and to choose the best therapeutic approach for HNSCC patients. Hyaluronan (HA), an important glycosaminoglycan component of the extracellular matrix (ECM), and its major cell surface receptor, CD44, have been suggested to be important cellular mediators influencing tumor progression and treatment resistance in head and neck cancer. HNSCC contains a small subpopulation of cells that exhibit a hallmark of CD44-expressing cancer stem cell (CSC) properties with self-renewal, multipotency, and a unique potential for tumor initiation. HA has been shown to stimulate a variety of CSC functions including self-renewal, clone formation and differentiation. This review article will present current evidence for the existence of a unique small population of CD44v3^highALDH^high-expressing CSCs in HNSCC. A special focus will be placed on the role of HA/CD44-induced oncogenic signaling and histone methyltransferase, DOT1L activities in regulating histone modifications (via epigenetic changes) and miRNA activation. Many of these events are essential for the CSC properties such as Nanog/Oct4/Sox2 expression, spheroid/clone formation, self-renewal, tumor cell migration/invasion, survival and chemotherapeutic drug resistance in HA-activated head and neck cancer. These newly-discovered HA/CD44-mediated oncogenic signaling pathways delineate unique tumor dynamics with implications for defining the drivers of HNSCC progression processes. Most importantly, the important knowledge obtained from HA/CD44-regulated CSC signaling and functional activation could provide new information regarding the design of novel drug targets to overcome current therapeutic drug resistance which will have significant treatment implications for head and neck cancer patients.

Genetic Variation in CD166 Gene and Its Association with Bladder Cancer Risk in North Indian Population

Adhesion molecules play a key role in cancer progression and tumorigenesis. Genetic polymorphism of adhesion molecules may alter the normal functioning thereby leading to bladder cancer susceptibility. Hence we aimed to evaluate three SNPs of CD166 gene (CD166rs6437585 C/T, CD166rs10511244 C/T, and CD166rs1157 A/G) in bladder cancer patients and normal controls of North Indian population. A total of 270 healthy controls and 240 confirmed bladder cancer patients were recruited for this study. Three SNPs of CD166 gene viz. CD166rs6437585 C/T, CD166rs10511244 C/T, and CD166rs1157 A/G were selected for this study. CD166rs6437585 C/T and CD166rs10511244 C/T were genotyped by Taqman allelic discrimination assay and CD166rs1157 A/G was genotyped by PCR-RFLP. The statistical analysis was done using the SPSS software, version 16.0 (SPSS, Chicago, IL), and p < 0.05 was considered statistically significant. Haplotypic analysis was done by using SNP analyzer version 1.2A. CD166rs6437585 C/T and CD166rs10511244 C/T showed significant association with reduced risk in bladder cancer while CD166rs1157 A/G showed significant high risk along with association at genotypic and allelic levels. Haplotypic analysis showed 1.8-folds risk in CCG combination, whereas CTA and TCG showed significant association with reduced risk. Further stratification on the basis of smoking, tumor grade/stage and BGC therapy revealed no association of these three polymorphic sites of CD166. Our study suggests that CD166rs6437585 C/T and CD166rs10511244 C/T are predictive for the reduced risk of bladder cancer, whereas CD166rs1157 A/G had shown significant association with high risk of bladder cancer in North Indians. This somehow suggests that CD166rs1157 A/G can be used as a marker for risk prediction of bladder cancer.

Matrix Hyaluronan Promotes Specific MicroRNA Upregulation Leading to Drug Resistance and Tumor Progression

Solid tumor invasion, metastasis and therapeutic drug resistance are the common causes for serious morbidity and cancer recurrence in patients. A number of research studies have searched for malignancy-related biomarkers and drug targets that are closely linked to tumor cell properties. One of the candidates is matrix hyaluronan (HA), which is known as one of the major extracellular matrix (ECM) components. HA serves as a physiological ligand for surface CD44 molecule and also functions as a bio-regulator. The binding of HA to CD44 has been shown to stimulate concomitant activation of a number of oncogenic pathways and abnormal cellular processes in cancer cells and cancer stem cells (CSCs). MicroRNAs (miRNAs) belong to a class of small RNAs containing ~20–25 nucleotides and are known to promote aberrant cellular functions in cancer cells. In this article, I have focused on the role of HA interaction with CD44 and several important signaling molecules in the regulation of unique miRNAs (e.g., miR-21, miR-302 and miR-10b) and their downstream targets leading to multiple tumor cell-specific functions (e.g., tumor cell growth, drug resistance and metastasis) and cancer progression. This new knowledge could provide the groundwork necessary for establishing new tumor markers and developing important, novel drugs targeted against HA/CD44-associated tumor progression, which can be utilized in the therapeutic treatment of metastatic cancer patients.

Prognostic Significance of Lymphatic Vessel Density Detected by D2-40 and Its Relation to Claudin-4 Expression in Prostatic Adenocarcinoma

Background Lymphovascular invasion is an important pathway of metastatic spread and regional lymph node metastasis is the major prognostic factor in prostatic adenocarcinoma. D2-40 is used to identify the lymphatic vessels and to assess the lymphatic vessel density (LVD). Expression of claudin-4 may be related to invasion and progression of carcinoma cells in several primary tumors. Aim To evaluate intra- and peritumoral LVD through immunohistochemical expression of D2-40 in relation to claudin-4 expression and clinicopathological parameters in prostatic adenocarcinoma. Materials and Methods Immunohistochemical staining procedure was performed on 53 paraffin-embedded blocks of radical prostatectomy specimens for prostatic adenocarcinoma using anti D2-40 and claudin-4 antibodies. Sections were evaluated for mean LVD in intratumoral and peritumoral tissues assessed by D2-40 expression. Results LVD in intratumoral tissues was significantly lower compared with peritumoral areas (P = .0001). Peritumoral mean LVD was significantly higher in cases with lymphovascular invasion (P = .041) and in cases with positive lymph node metastasis (P = .003) than intratumoral mean LVD. High claudin-4 expression was significantly correlated with high tumor grade (P = .0001), lymphovascular invasion (P = .006), and positive lymph node metastasis (P = .004). High claudin-4 expression was significantly associated with increased mean LVD in peritumoral tissues. Conclusion Increased peritumoral mean LVD in prostatic adenocarcinoma is associated with lymphovascular invasion and positive lymph node metastasis. High claudin-4 expression is associated with high tumor grade, lymphocascular invasion, positive lymph node metastasis, and high mean peritumoral LVD suggesting that D2-40 and claudin-4 may represent different mechanisms of lymphatic vessel invasion with both biomarkers is related to poor prognosis.

The role of tight junctions in cancer metastasis

Over the last decade, it has become apparent that the tight junction (TJ) is a key component in tumour progression and metastasis. In addition to its role in the control of paracellular diffusion of ions and certain molecules, the TJ has a vital role in maintaining cell to cell adhesion and tissue integrity. Changes in the expression and/or distribution of TJ proteins can result in loss in cohesion of the TJ structure, which in turn results in the ability of cancer cells to become invasive and then ultimately lead to the metastasis of cancer cells. This review will discuss recent insights into how TJ are involved in the process of tumour metastasis.

Circulating Tumor Cells in Metastatic Breast Cancer: A Prognostic and Predictive Marker

The role of circulating tumor cells (CTCs) as a marker for disease progression in metastatic cancer is controversial. The current review will serve to summarize the evidence on CTCs as a marker of disease progression in patients with metastatic breast cancer. The immunohistochemistry(IHC)-based CellSearch^® is the only FDA-approved isolation technique for quantifying CTCs in patients with metastatic breast cancer. We searched PubMed and Web of Knowledge for clinical studies that assessed the prognostic and predictive value of CTCs using IHC-based isolation. The patient outcomes reported include median and Cox-proportional hazard ratios for overall-survival (OS) and progression-free-survival (PFS). All studies reported shorter OS for CTC-positive patients versus CTC-negative. A subset of the selected trials reported significant lower median PFS for CTC-positive patients. The reported trials support the utility of CTC enumeration for patient prognosis. But further studies are required to determine the utility of CTC enumeration for guiding patient therapy. There are three clinical trials ongoing to test this hypothesis. These studies, and others, will further establish the role of CTCs in clinical practice.

Potential Urinary Protein Biomarker Candidates for the Accurate Detection of Prostate Cancer among Benign Prostatic Hyperplasia Patients

Globally, Prostate cancer (PCa) is the most frequently occurring non-cutaneous cancer, and is the second highest cause of cancer mortality in men. Serum prostate specific antigen (PSA) has been the standard in PCa screening since its approval by the American Food & Drug Administration (FDA) in 1994. Currently, PSA is used as an indicator for PCa - patients with a serum PSA level above 4ng/mL will often undergo prostate biopsy to confirm cancer. Unfortunately fewer than ~30% of these men will biopsy positive for cancer, meaning that the majority of men undergo invasive biopsy with little benefit. Despite PSA's notoriously poor specificity (33%), there is still a significant lack of credible alternatives. Therefore an ideal biomarker that can specifically detect PCa at an early stage is urgently required. The aim of this study was to investigate the potential of using deregulation of urinary proteins in order to detect Prostate Cancer (PCa) among Benign Prostatic Hyperplasia (BPH). To identify the protein signatures specific for PCa, protein expression profiling of 8 PCa patients, 12 BPH patients and 10 healthy males was carried out using LC-MS/MS. This was followed by validating relative expression levels of proteins present in urine among all the patients using quantitative real time-PCR. This was followed by validating relative expression levels of proteins present in urine among all the patients using quantitative real time-PCR. This approach revealed that significant the down-regulation of Fibronectin and TP53INP2 was a characteristic event among PCa patients. Fibronectin mRNA down-regulation, was identified as offering improved specificity (50%) over PSA, albeit with a slightly lower although still acceptable sensitivity (75%) for detecting PCa. As for TP53INP2 on the other hand, its down-regulation was moderately sensitive (75%), identifying many patients with PCa, but was entirely non-specific (7%), designating many of the benign samples as malignant and being unable to accurately identify more than one negative.

Apoptotic and anti-metastatic effects of the whole skin of Venenum bufonis in A549 human lung cancer cells

In the present study, the effects of the whole skin of Venenum bufonis on apoptotic and anti-invasive activity in A549 human lung cancer cells were investigated. Treatment with extract of the whole skin of V. bufonis (SVB) resulted in a significant decrease in cell growth of A549 cells, depending on dosage, which was associated with apoptosis induction, as proved by chromatin condensation and accumulation of apoptotic fraction. SVB treatment induced expression of death receptor-related proteins, such as death receptor 4, which further triggered activation of caspase-8 and cleavage of Bid. In addition, the increase in apoptosis by SVB treatment was correlated with dysfunction of mitochondria, activation of caspase-9 and -3, downregulation of IAP family proteins, such as XIAP, cIAP-1 and cIAP-2, and concomitant degradation of activated caspase-3-specific target proteins, such as poly (ADP-ribose) polymerase and β-catenin proteins. However, z-DEVD-fmk, a caspase-3-specific inhibitor, blocked SVB-induced apoptosis and increased the survival rate of SVB-treated cells, indicating that activation of caspase-3 plays a key role in SVB-induced apoptosis. In addition, within concentrations that were not cytotoxic to A549 cells, SVB induced marked inhibition of cell motility and invasiveness. Activities of matrix metalloproteinase (MMP)-2 and MMP-9 in AGS cells were dose-dependently inhibited by treatment with SVB, and this was also correlated with a decrease in expression of their mRNA and proteins, and upregulation of tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2 mRNA expression. Further studies are needed; however, the results indicated that SVB induces apoptosis of A549 cells through a signaling cascade of death receptor-mediated extrinsic as well as mitochondria-mediated intrinsic caspase pathways. Our data also demonstrated that MMPs are critical targets of SVB-induced anti-invasiveness in A549 cells.

Altered levels of Ets-1 transcription factor and matrix metalloproteinases in melanocytes from patients with vitiligo

BACKGROUND

Vitiligo is characterized by the loss of functional melanocytes from the epidermis. Repigmentation in vitiligo is initiated by activation, proliferation and migration of melanoblasts from the outer root sheath of hair follicles, or melanocytes from the border area of vitiligo lesions, into the depigmented epidermis. Cell migration plays a crucial role during repigmentation in vitiligo.

OBJECTIVES

To investigate the role of matrix metalloproteinases (MMPs) and their transcription factor Ets-1 in vitiligo.

METHODS

Skin biopsies were taken from 15 patients with vitiligo and six controls to culture melanocytes from clinically active perilesional and normal skin. Expression of MMP-1, MMP-2, MMP-9 and Ets-1 was examined by reverse transcriptase-polymerase chain reaction analysis. Expression of Ets-1 was also confirmed with Western blot analysis. Activity of MMP-2 and MMP-9 was assessed using gelatin zymography.

RESULTS

The activity of MMP-2 and MMP-9 was significantly lower in patients with vitiligo compared with the controls. The expression of MMP-2 and MMP-9 was also significantly lower in patients with vitiligo. There was no expression of Ets-1 transcription factor at either the transcriptional or translational level in melanocytes cultured from patients with vitiligo.

CONCLUSION

The absence of a basal level of expression of Ets-1 significantly decreases the expression and activity of MMP-2 and MMP-9. Significant decreases in MMP-2 and MMP-9 activity could possibly reduce the migration of melanocyte precursors (melanoblasts) from the outer root sheath of hair follicles or migration of melanocytes from the border of vitiligo lesions into clinically depigmented epidermis which is crucial to the repigmentation of vitiliginous skin.

Identification of six potential markers for the detection of circulating canine mammary tumour cells in the peripheral blood identified by microarray analysis

The presence of circulating tumour cells (CTCs) in the peripheral blood is a prognostic factor for survival of human breast cancer patients. CTCs in the peripheral blood of dogs with mammary tumours have not been reported definitively. The present pilot study identifies mRNA markers for CTCs by comparing the transcriptome of canine mammary carcinoma cell lines CMM26 and CMM115 and peripheral blood leucocytes (PBLs). Genes with a 200-fold or higher mRNA expression in carcinoma cell lines were tested for specificity and sensitivity to detect CTCs using reverse transcriptase polymerase chain reaction (PCR). Six mRNA markers, AGR2, ATP8B1, CRYAB, F3 IRX3 and SLC1A1 were expressed in cell lines, but not PBL. All PCRs were able to detect one carcinoma cell admixed in 10(6) or more PBLs. The six mRNA markers may be suitable for detection of canine mammary CTCs and allow the analysis of their spatiotemporal distribution in dogs with mammary tumours.

Expression of claudin-1 and -7 in clear cell renal cell carcinoma and its clinical significance

Purpose

We investigated the correlations between the expression of claudin-1 and claudin-7 in clear cell renal cell carcinoma (clear cell RCC) and clinical parameters.

Materials and Methods

The subjects of this study were 119 patients with confirmed clear cell RCC between January 2000 and December 2007. Their RCC tissues were immunohistochemically stained for claudin-1 and claudin-7. The correlations between the expression of claudin and parameters such as sex, age, body mass index (BMI), tumor size, TNM stage, Furhman nuclear grade, postoperative distant metastasis, and cancer-specific survival were analyzed.

Results

Among the total 119 subjects, claudin-1 was expressed in 18 (15.1%) and claudin- 7 in 31 (26.1%). Claudin-1 was expressed in patients who were older (p=0.007), who had a greater tumor size (p=0.001), who had a higher pathologic T stage (p=0.009), who had preoperative distant metastasis (p=0.035), and who had a higher Furhman nuclear grade (p=0.004). Claudin-7 was expressed only in patients who had a higher Furhman nuclear grade (p=0.031). The risk of postoperative distant metastasis was associated with the expression of claudin-1 (p<0.001) but not with the expression of claudin-7 (p=0.668). The expression of claudin-1 and -7 was not associated with cancer-specific survival (p>0.05).

Conclusions

In clear cell RCC, claudin-1 was expressed in patients who were older and who had a greater tumor size, who had higher T or M stages, and who had a higher Furhman nuclear grade. The expression of claudin-1 was associated with a higher risk of postoperative distant metastasis.

Functional polymorphisms in CD166/ALCAM gene associated with increased risk for breast cancer in a Chinese population

Activated Leukocyte Cell Adhesion Molecules (ALCAM, also called CD166, MEMD) are cell surface immunoglobulins that are considered to be prognostic markers for breast cancer. CD166/ALCAM has gained increasing attention because of its significant association with tumor progression and the metastatic spread of breast cancer. Two polymorphisms have been identified in the CD166/ALCAM gene: 5'UTR C/T (rs6437585) and 3'UTR A/G (rs11559013). We analyzed the genotypes of 1033 individuals with breast cancer, and 1116 controls; odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using logistic regression. The effects and functions of polymorphisms were examined using luciferase gene expression assays and real-time PCR analyses. Our data demonstrated that individuals with the rs6437585 CT + TT genotype had an OR of 1.38 (95% CI, 1.11-1.72) for developing breast cancer, compared to those with the CC genotype. The T allele increased the risk of breast cancer in a dose-dependent manner (P (trend) < 0.001). However, there were no significant differences found between cases and controls at the rs11559013 A/G site. Additional experiments that we performed, which focused on reporter gene expression driven by CD166/ALCAM promoters, demonstrated that the presence of an rs6437585 T allele led to greater transcriptional activity than the rs6437585 C allele. This was consistent with the increased cancer risk that we observed in our case-control analysis.

Surgical injury enhances the expression of genes that mediate breast cancer metastasis to the lung

OBJECTIVE

This study was conducted to test the hypothesis that surgery induces changes at the expression level of genes implicated in metastasis, thus leading to accelerated postoperative metastatic tumor growth.

SUMMARY BACKGROUND DATA

Surgical resection of the primary tumor is a necessary and effective treatment for breast cancer patients. However, studies from both animals and humans have shown that surgery potentiates the growth of minimal residual neoplastic disease.

METHODS

: Female BALB/c mice were inoculated with metastatic murine mammary adenocarcinoma 4T1-green fluorescent protein (GFP) cells in the mammary fat pad (3 × 10⁵/mouse), and divided into a surgery group (n = 12) in which the flank tumor was completely resected after 21 day growth and a control (no surgery) group (n = 12). Metastatic tumor burden was assessed by both macroscopic metastatic nodule count and clonogenic assay. Mitotic and apoptotic indices were established using a combination of hematoxylin-eosin histology and Ki-67 immunohistochemistry. Green fluorescent protein (GFP) expressing tumor cells were isolated using FACS sorting, and RNA was extracted. The RT² Profiler PCR Array mouse Cancer Pathway Finder was used to determine and compare the mRNA levels of 84 genes involved in metastasis in both groups.

RESULTS

Excision of the primary tumor was associated with increased systemic metastatic burden (P = 0.001). Postoperative metastases exhibited increased proliferation (P = 0.001), but no reduction in apoptosis. The quantitative real-time polymerase chain reaction array data indicate that surgery significantly upregulated the expression of Itgb3, Egfr, Hgf, Igf1, Pdgfb, Tnfα, Vegfa, Vegfc, and MMP9 genes, and led to the down regulation of Cdkn2a, Cdh1, and Syk genes. Increased expression of ITGB3 and MMP9 was further confirmed at the protein level by Western blot.

CONCLUSIONS

Removal of the primary tumor led to a progressive phenotype of lung metastases that exhibited upregulation of genes involved in adhesion, invasion, and angiogenesis.

Hyaluronan-CD44 interaction promotes c-Src-mediated twist signaling, microRNA-10b expression, and RhoA/RhoC up-regulation, leading to Rho-kinase-associated cytoskeleton activation and breast tumor cell invasion

Dysregulation of microRNAs is observed in many cancers, including breast cancer. In particular, miR-10b appears to play an important role in tumor cell invasion and breast cancer progression. In this study, we investigated hyaluronan (HA)-induced CD44 (a primary HA receptor) interaction with c-Src kinase and the transcriptional factor, Twist, in breast tumor cells (MDA-MB-231 cells). Our results indicate that HA binding to CD44 promotes c-Src kinase activation, which, in turn, increases Twist phosphorylation, leading to the nuclear translocation of Twist and transcriptional activation. Further analyses reveal that miR-10b is controlled by an upstream promoter containing the Twist binding site(s), whereas ChIP assays demonstrate that stimulation of miR-10b expression by HA/CD44-activated c-Src is Twist-dependent in breast tumor cells. This process results in the reduction of a tumor suppressor protein (HOXD10), RhoA/RhoC up-regulation, Rho-kinase (ROK) activation, and breast tumor cell invasion. Treatment of MDA-MB-231 cells with PP2 (a c-Src inhibitor) or Twist-specific siRNAs effectively blocks HA-mediated Twist signaling events, abrogates miR-10b production, and increases HOXD10 expression. Subsequently, this c-Src/Twist signaling inhibition causes down-regulation of RhoA/RhoC expression and impairment of ROK-regulated cytoskeleton function (e.g. tumor cell invasion). To further evaluate the role of miR-10b in RhoGTPase signaling, MDA-MB-231 cells were also transfected with a specific anti-miR-10b inhibitor in order to silence miR-10b expression and block its target functions. Our results demonstrate that anti-miR-10b inhibitor not only enhances HOXD10 expression but also abrogates HA/CD44-mediated tumor cell behaviors in breast tumor cells. Taken together, these findings indicate that the HA-induced CD44 interaction with c-Src-activated Twist plays a pivotal role in miR-10b production, leading to the down-regulation of tumor suppressor protein (HOXD10), RhoGTPase-ROK activation, and tumor cell invasion. All of these events are critical prerequisite steps for the acquisition of metastatic properties by human breast cancer cells.

Correlation between Claudins Expression and Prognostic Factors in Prostate Cancer

Purpose

The purpose of this study was to evaluate the correlation between the expression of claudins and prognostic factors in patients with prostate cancer.

Materials and Methods

The subjects of this study were 48 patients who had undergone surgery for prostate cancer. The Gleason score (6 or lower, 7 or higher), prostate-specific antigen (PSA) level, T stage, biochemical recurrence, local recurrence, and distant metastasis were compared according to the expression of claudin-1 and claudin-5 in prostate cancer.

Results

In the group with a low expression of claudin-1, the Gleason score was 7 points or higher in 18 cases (82%) and 6 points or lower in 4 cases (18%). In the group with a high expression of claudin-1, the Gleason score was 7 points or higher in 13 cases (50%) and 6 points or lower in 13 cases (50%). Thus, the low-expression group had more cases with a Gleason score of 7 or higher (p=0.022). The group with a low expression of claudin-5 also had more cases with a Gleason score of 7 or higher (p=0.011). The mean PSA values in the groups with a low and high expression of claudin-1 were 9.6 ng/ml and 5.6 ng/ml, respectively (p=0.007). A low expression of claudin-5 was also associated with a high PSA value (p=0.002). There was no statistical difference in the expression of claudin-1 and claudin-5 by T stage, biochemical recurrence, local recurrence, or distant metastasis.

Conclusions

The low expression of claudin-1, claudin-5 was associated with a Gleason score of 7 or higher and a high PSA value in prostate cancer.

Survivin is a potential mediator of prostate cancer metastasis

PURPOSE

We examined whether Survivin expression is associated with an increased risk of metastasis in prostate cancer.

METHODS AND MATERIALS

A total of 205 patients with T1 (23%) and T2 (77%) prostate cancer were treated with conventional external beam radiation therapy from 1991 to 1993 at the Massachusetts General Hospital. Of the patients, 62 had adequate and suitable-stained tumor material for Survivin analysis. Median follow-up was 102 months (range, 5-127 months). Distant failure was determined on the basis of clinical criteria. In preclinical studies, replication-deficient adenovirus encoding phosphorylation-defective Survivin Thr34→Ala dominant-negative mutant pAd-S(T34A) or short hairpin RNA (shRNA) was used to inhibit Survivin in prostate cancer models, and the cell motility, morphology, and metastasis were investigated.

RESULTS

Our correlative data on men with early-stage (T1/T2) prostate cancers treated at Massachusetts General Hospital by definitive radiotherapy indicated that overexpression of Survivin (positive staining in ≥10% cells) was associated with a significantly increased risk for the subsequent development of distant metastasis (p = 0.016) in the univariate analysis. In the multivariate analysis, overexpression of Survivin remained an independent predictor of distant metastasis (p = 0.008). The inhibition of Survivin dramatically inhibited invasiveness of prostate cancer cells in the in vitro invasion assay and spontaneous metastasis in the Dunning prostate cancer in vivo model. Furthermore, attenuation of Survivin resulted in changes in the microtubule cytoskeleton, loss of cellular polarity, and loss of motility.

CONCLUSIONS

This study suggests that Survivin may be a potentially important prognostic marker and promising therapeutic target in metastatic prostate cancer.

Cell adhesion molecules: role and clinical significance in cancer

There is a growing body of evidence suggesting that alterations in the adhesion properties of neoplastic cells endow them with an invasive and migratory phenotype. Indeed, changes in the expression or function of cell adhesion molecules have been implicated in all steps of tumor progression, including detachment of tumor cells from the primary site, intravasation into the blood stream, extravasation into distant target organs, and formation of the secondary lesions. This review presents recent data regarding the role of cell adhesion molecules in tumor development and progress with concern to their clinical exploitation as potential biomarkers in neoplastic diseases.

Interference targeting the G-actin binding domain of N-WASP inhibits the invasion and metastasis of colon cancer cells

AIM: To examine the effect of intervention targeting the G-actin binding domain of N-WASP on the invasion and metastasis of colon cancer cells.

METHODS: Recombinant expression vector encoding the V motif of N-WASP was designed, constructed and transfected into human colon cancer cells (LoVo) to obtain stably expressed cell strain. Transwell assay was used to examine the change in the invasive ability of LoVo cells. Capture-ELISA assay was used to measure transferrin (Tfn) internalization, a hallmark of cell endocytosis. Furthermore, a mouse model of metastatic colon cancer was generated by injection of LoVo cells into the spleen of mice to observe liver metastasis.

RESULTS: The recombinant plasmid was successfully constructed and transfected into LoVo cells. Cells transfected with the recombinant plasmid showed a low invasive ability when compared with untransfected cells or cells transfected with empty plasmid. The number of recombinant plasmid-transfected cells passing through the Transwell membrane were significantly lower than those of untransfected cells or cells transfected with empty plasmid (42.15 ± 7.35 vs 85.25 ± 6.16 and 84.35 ± 7.99, both P < 0.05). Capture-ELISA assay showed that internalization of transferrin in cells transfected with recombinant plasmid was attenuated dramatically when compared to control cells. Animal experiments showed that the number of mice developing liver metastasis in mice injected with recombinant plasmid-transfected cells was significantly lower than that in mice injected with untransfected or empty plasmid-transfected cells (2/12 vs 10/12 and 10/12).

CONCLUSION: Interference targeting the G-actin binding domain of N-WASP is able to inhibit the invasion and metastasis of colon caner cells.

Hyaluronan-mediated CD44 activation of RhoGTPase signaling and cytoskeleton function promotes tumor progression

Hyaluronan (HA), a major component of the extracellular matrix (ECM), is enriched in many types of tumors. In cancer patients HA concentrations are usually higher in malignant tumors than in corresponding benign or normal tissues, and in some tumor types the level of HA is predictive of malignancy. HA is often bound to CD44 isoforms which are ubiquitous, abundant, and functionally important cell surface receptors. This article reviews the current evidence for HA/CD44-mediated activation of the ankyrin-based cytoskeleton and RhoGTPase signaling during tumor progression. A special focus is placed on the role of HA-mediated CD44 interaction with unique downstream effectors (e.g., the cytoskeletal protein, ankyrin and/or various GTPases (e.g., RhoA, Rac1 and Cdc42)) in coordinating intracellular signaling pathways (e.g., Ca(2+) mobilization, Rho signaling, PI3 kinase-AKT activation, NHE1-mediated cellular acidification, transcriptional upregulation and cytoskeletal function) and generating the concomitant onset of tumor cell activities (e.g., tumor cell adhesion, growth, survival, migration and invasion) and tumor progression. I believe this information will provide valuable new insights into poorly understood aspects of solid tumor malignancy. Furthermore, the new knowledge concerning HA/CD44-mediated oncogenic signaling events will have potentially important clinical utility, and could establish CD44 and its associated signaling molecules as important tumor markers for the early detection and evaluation of oncogenic potential. It could also serve as ground work for the future development of new drug targets to inhibit HA/CD44-mediated tumor metastasis and cancer progression.

Single cell adhesion measuring apparatus (SCAMA): application to cancer cell lines of different metastatic potential and voltage-gated Na+ channel expression

We have developed a simple yet effective apparatus, based upon negative pressure directed to the tip of a micro-pipette, to measure the adhesiveness of single cells. The "single cell adhesion measuring apparatus" (SCAMA) could differentiate between the adhesion of strongly versus weakly metastatic cancer cells as well as normal cells. Adhesion was quantified as "detachment negative pressure" (DNP) or "DNP relative to cell size" (DNPR) where a noticeable difference in cell size was apparent. Thus, for rat and human prostate and human breast cancer cell lines, adhesiveness (DNPR values) decreased in line with increased metastatic potential. Using the SCAMA, we investigated the effect of tetrodotoxin (TTX), a specific blocker of voltage-gated Na(+) channels (VGSCs), on the adhesion of rat and human prostate cancer cell lines of markedly different metastatic potential. Following pretreatment with TTX (48 h with 1 microM), the adhesion values for the Mat-LyLu cells increased significantly 4.3-fold; there was no effect on the AT-2 cells. For the strongly metastatic PC-3M cells, TTX treatment caused a significant (approximately 30%) increase in adhesion. The adhesion of PNT2-C2 ("normal") cells was not affected by the TTX pretreatment. The TTX-induced increase in the adhesiveness of the strongly metastatic cells was consistent with the functional VGSC expression in these cells and the proposed role of VGSC activity in metastatic cell behaviour. In conclusion, the SCAMA, which can be constructed easily and cheaply, offers a simple and effective method to characterise single-cell adhesion and its modulation.

Hepatic ischemia/reperfusion injury is prevented by a novel matrix metalloproteinase inhibitor, ONO-4817

BACKGROUND

Matrix metalloproteinases (MMPs) play an important role in inflammation and neoplastic invasion and metastasis. Little is known about the effects of MMP inhibitors on hepatic ischemia/reperfusion injury. The aim of this study is to examine the inhibitory effects of ONO-4817 (oral inhibitor of MMPs) in rats.

METHODS

Hepatic ischemia/reperfusion was induced in male Wister rats by clamping the portal vein and hepatic artery. The animals were randomized into an ONO-4817 group (300 mg/kg body weight per/day) and a vehicle group by oral gavage of a test substance. Serum alanine aminotransferase, histologic changes, gelatinolytic activity, MMP-2 and MMP-9 activities, tissue inhibitor of metalloproteinase 2 (TIMP-2) messenger RNA (mRNA) levels, and mRNA and serum levels of tumor necrosis factor alpha (TNFalpha) and interleukin 1beta (IL-1beta) were measured in both groups.

RESULTS

ONO-4817 prevented ischemia/reperfusion injury to the hepatocytes as shown by significant reductions of serum alanine aminotransferase and less severe histologic changes. Gelatinolytic activity was inhibited markedly in the liver of the ONO-4817 group as demonstrated by film in situ zymography. MMP-9 and MMP-2 activities also were inhibited in the ONO-4817 group as shown by gelatin zymography. TIMP-2 mRNA levels showed no significant differences between the 2 groups. TNFalpha mRNA showed no downregulation, but IL-1beta mRNA was downregulated in the liver of the ONO-4817 group 1 to 3 hours after reperfusion. Serum levels of TNFalpha and IL-1beta showed a significant decrease in the ONO-4817 group, compared with the vehicle group after reperfusion.

CONCLUSIONS

Hepatic ischemia/reperfusion injury was improved by a novel MMP inhibitor, ONO-4817, not only by inhibition of gelatinolytic activity but also by a decrease in release of inflammatory cytokines.

Angiomotin and angiomotin like proteins, their expression and correlation with angiogenesis and clinical outcome in human breast cancer

Backgound

Angiomotin is a newly discovered molecule that regulates the migration and tubule formation of endothelial cells. It therefore has been implicated in the control of angiogenesis under physiological and pathological conditions. This study examined the expression of angiomotin and its analogues, angiomotin-like 1 (L1) and -like 2 (L2) in breast tumour tissues, and analysed their correlation with angiogenesis and clinical outcomes.

Methods

Human breast tissues (normal n = 32 and tumours n = 120) were used. The levels of expression of angiomotin, L1 and L2 were determined using reverse transcription PCR. Microvessels were stained using antibodies against PECAM, von Willebrand factor (factor 8, or vWF) and VE-cadherin. The transcript levels of angiomotin and its analogues were assessed against the clinical and pathological background, including long term survival (120 months).

Results

Breast cancer tissues expressed significantly higher levels of angiomotin transcript, compared with normal mammary tissues (33.1 ± 11 in normal versus 86.5 ± 13.7 in tumour tissues, p = 0.003). Both L1 and L2 were seen at marginally higher levels in tumour than normal tissues but the difference was not statistically significant. Levels of angiomotin were at significantly higher levels in grade 2 and grade 3 tumours compared with grade 1 (p < 0.01 and p = 0.05 respectively). The levels of angiomotin in tumours from patients who had metastatic disease were also significantly higher than those patients who remained disease free (p = 0.03). Multivariate analysis indicated that angiomotin transcript was an independent prognostic factor (p = 0.031). No significant correlations were seen between angiomotin-L1 and L2 with the clinical outcome. Furthermore, high levels of angiomotin transcript were associated with shorter overall survival (p < 0.05). There was a high degree of correlation between levels of vW factor and that of angiomotin (p < 0.05), but not angiomotin-L1 and angiomotin-L2.

Conclusion

Angiomotin, a putative endothelial motility factor, is highly expressed in human breast tumour tissues and linked to angiogenesis. It links to the aggressive nature of breast tumours and the long term survival of the patients. These data point angiomotin as being a potential therapeutic target.

Circulating tumor cells in patients with breast cancer: possible predictor of micro-metastasis in bone marrow but not in sentinel lymph nodes

BACKGROUND

Blood and lymphatic circulation are the major routes during metastatic spread of breast cancer cells. Despite the predictive and prognostic value of bone marrow (BM) micro-metastasis, repeated and frequent BM aspirations may not be easily accepted by patients. We try to establish the role of circulating tumor cells as a predictor for micro-metastasis in BM and sentinel lymph node (SLN) as well as to identify the association between micro-metastasis in blood and lymphatic circulation. We prospectively studied 47 breast cancer patients without overt metastasis. Bilateral BM samples and blood samples were obtained before surgery and subsequently handled using magnetic-activated cell separation (MACS) followed by immunocytochemistry (ICC). SLN was examined by hematoxylin and eosin (H and E) staining and ICC.

RESULTS

Blood and BM micro-metastasis were detected in 16 (35%) and 25 (54%) of 47 patients. SLN micro-metastasis were detected in 13 (27.7%) and 22 (46.8%) patients using H and E and ICC, respectively. All the patients with circulating tumor cells had micro-metastasis in BM, whereas 9 of 25 (36%) patients with micro-metastasis in BM had no circulating tumor cells (P < 0.001). On the other hand, there is no correlation between circulating tumor cells and micro-metastasis in SLNs detected by either H and E (P = 0.52) or ICC (P = 0.36). We found that the presence of circulating tumor cells might predict BM micro-metastasis but not SLN micro-metastasis. It is also interesting to find that the presence of SLN micro-metastasis does not necessarily correlate with the presence of micro-metastasis in BM and blood.

TaqMan®-based quantification of invasive cells in the chick embryo metastasis assay

The chick embryonic metastasis (CEM) assay is a fast in vivo method to investigate the invasive properties of tumor cells. Until now, most quantification methods were semiquantitative and time-consuming. Here we describe a rapid quantification method using TaqMan® technology to quantify the invaded tumor cells in the chorioallantoic membrane of fertilized eggs. This method is based on specific detection of human ALU sequences. Moreover, it provides high sensitivity over a wide linearity range.

The detection of circulating breast cancer cells in blood

At present, sampling of the lymph nodes or bone marrow for the detection of regions of metastatic disease in patients with breast cancer can only be undertaken at the time of initial diagnosis and surgery. However, the sampling of these tissues and the methods used are inaccurate, time consuming, and cannot be used for easy routine screening to determine disease recurrence and response to treatment. Because of the problems encountered with current methods and tissues sampled at the time of breast cancer diagnosis, this review discusses the urgent requirement for and potential development of a quick, simple, and accurate diagnostic test utilising the haematogenous system, a source of circulating tumour cells in patients with breast cancer, and highly sensitive molecular biological techniques, such as reverse transcription polymerase chain reaction. In addition, this review also highlights potential problems that may be encountered and should be avoided when devising such a test.

PT-100, a small molecule dipeptidyl peptidase inhibitor, has potent antitumor effects and augments antibody-mediated cytotoxicity via a novel immune mechanism

The amino boronic dipeptide, PT-100 (Val-boro-Pro), a dipeptidyl peptidase (DPP) inhibitor, has been shown to up-regulate gene expression of certain cytokines in hematopoietic tissue via a high-affinity interaction, which appears to involve fibroblast activation protein. Because fibroblast activation protein is also expressed in stroma of lymphoid tissue and tumors, the effect of PT-100 on tumor growth was studied in mice in vivo. PT-100 has no direct cytotoxic effect on tumors in vitro. Oral administration of PT-100 to mice slowed growth of syngeneic tumors derived from fibrosarcoma, lymphoma, melanoma, and mastocytoma cell lines. In WEHI 164 fibrosarcoma and EL4 and A20/2J lymphoma models, PT-100 caused regression and rejection of tumors. The antitumor effect appeared to involve tumor-specific CTL and protective immunological memory. PT-100 treatment of WEHI 164-inoculated mice increased mRNA expression of cytokines and chemokines known to promote T-cell priming and chemoattraction of T cells and innate effector cells. The role of innate activity was further implicated by observation of significant, although reduced, inhibition of WEHI 164 and A20/2J tumors in immunodeficient mice. PT-100 also demonstrated ability to augment antitumor activity of rituximab and trastuzumab in xenograft models of human CD20(+) B-cell lymphoma and HER-2(+) colon carcinoma where antibody-dependent cytotoxicity can be mediated by innate effector cells responsive to the cytokines and chemokines up-regulated by PT-100. Although CD26/DPP-IV is a potential target for PT-100 in the immune system, it appeared not to be involved because antitumor activity and stimulation of cytokine and chemokine production was undiminished in CD26(-/-) mice.

RRR-alpha-tocopheryl succinate inhibits human prostate cancer cell invasiveness

RRR-alpha-tocopheryl succinate (alpha-vitamin E succinate, VES), one of the vitamin E derivatives, can effectively inhibit the proliferation of human prostate cancer cells. However, little is known about its effect on prostate cancer cell invasive ability. Tumor metastasis is a complex process and the extracellular matrix (ECM) is the first barrier that tumor cells encounter. Therefore, we tested the effect of VES on the invasion of different prostate tumor cells, PC-3, DU-145, and LNCaP, through Matrigel, a reconstituted ECM, using an in vitro cell invasion assay. The invasion of PC-3 and DU-145 cells through Matrigel was inhibited by 20 microM VES after treating for 24 h. The condition did not alter cell survival, cell cycle, cell adhesion or cell motility. We further investigated whether the ability of VES to inhibit prostate cancer cell invasiveness was associated with its ability to inhibit the activity of matrix metalloproteinases (MMPs), the key enzymes in the proteolysis of basement membrane during invasion. PC-3 and DU-145 cells that were treated with VES showed a significant reduction in the levels of MMP-9 in the culture medium. In contrast, LNCaP cells, which did not secrete MMP-9, were poorly invasive in Matrigel and were hardly affected by treatment with VES. This is the first report suggesting that VES inhibits human prostate cancer cell invasiveness and the reduction of secreted MMP-9 activity could be one of the contributory factors, which points to the potential use of VES in the prevention and therapy of prostate cancer invasion.

The significance of angiogenesis in malignant pheochromocytomas

The purpose of this study was to investigate tumor angiogenesis in a series of benign and malignant pheochromocytomas and to determine whether there is a correlation between angiogenesis and the presence of distant metastases. In this study, the CD31 monoclonal antibody was selected to measure intratumoral microvessel density. Nineteen patients with malignant pheochromocytomas and nineteen patients with benign pheochromocytomas who underwent operation were studied. In order to quantify intratumoral microvessel density, the total number of pixels of CD31-positive reactivity was assessed and expressed as a percentage of the total tissue area in the analyzed field. Analysis of variance revealed a statistically significant correlation between malignancy and intratumoral microvessel density (p = 0.0009). Although there was a considerable variability in the intratumoral microvessel density from tumor to tumor within both the benign and the malignant group, a percentage of more than 28.5% anti-CD31 stained area was found only in malignant tumors. In conclusion, this study shows that the mean intratumoral microvessel density in malignant pheochromocytomas is increased approximately twofold as compared with benign tumors. However, the clinical significance of this prognostic marker is rather weak, because only 4 of the 19 malignant pheochromocytomas had microvessel density higher than this threshold of 28.5%.

Correlation of CT enhancement, tumor angiogenesis and pathologic grading of pancreatic carcinoma

AIM: To study the correlation between pancreatic phase CT enhancement, intratumor microvessel density (MVD) and pathologic grading of pancreatic carcinoma and to evaluate the relationship between the degrees of CT enhancement and malignancy of pancreatic carcinoma.

METHODS: Thirty four patients with pancreatic carcinoma underwent CT scanning before resection. The enhancement degrees and forms of tumor were observed in pancreatic phase. The operative sample was stained with HE and CD34 marked by immunohistochemistry. MVD and histopathological grades of pancreatic carcinoma were examined. CT enhancement of the tumor, MVD counting in hot spot areas of neoplastic parenchymal cells and pathological grades of pancreatic carcinoma were comparatively analyzed.

RESULTS: Highly differentiated pancreatic adenocarcinoma was identified in 16 patients, moderately-differentiated tumor in 7 and poorly-differentiated in 11. Isodensity CT enhancement was demonstrated in 13 cases, slightly low density enhancement in 9, slightly low density enhancement with small cystic lesions in 9 and slightly low density enhancement with large cystic lesions in 3. The counting of MVD with CD34 marked by immunohistochemistry in hot spot areas of neoplastic parenchyma cells was small in 10 cases, medium in 16 and large in 8. The pathological grades correlated well with CT enhancement of the tumor (r = 0.7857, P < 0.001) and with MVD counting of tumor (r = 0.3613, P < 0.05). The CT enhancement of tumor correlated with MVD(r = 0.6768, P < 0.001).

CONCLUSION: There is an obvious and significant correlation between CT enhancement, pathological grades and MVD number in the hot spot areas of tumor. The extent of CT enhancement is inversely proportional to the malignant degree of pancreatic carcinoma, and to the MVD number in the hot spot areas of neoplastic parenchyma. The MVD in the hot spot areas of neoplastic parenchyma cells can also reflect the prognosis of the patients, and is directly proportional to the malignant degree of pancreatic carcinoma.

Cell adhesion molecules and adhesion abnormalities in prostate cancer

Prostate cancer, the leading male cancer in Western countries, has accelerated in its incidence in the past decade. Patients with prostate cancer frequently have a poor prognosis as a result of local or distant spread of cancer. This review summarises some of the recent progress made in understanding the biology of cancer metastasis with a special emphasis on the role of cell adhesion molecules and adhesion abnormalities. The molecular and cellular function of cell adhesion molecules, their role in cancer and cancer progression, the clinical impact of these molecules, and therapeutic considerations are also discussed.

Colorectal cancer metastatic phenotype stimulates production by fibroblasts of N-terminal peptide of type III collagen: clinical implications for prognosis

In this study we assessed whether the serum levels of the N-terminal peptide of type III collagen (PIIIP), an index of type III collagen synthesis, are influenced by colorectal cancer stage, and whether "in vitro" fibroblast growth and PIIIP production could be altered by tumor tissues obtained from metastatic and nonmetastatic colorectal cancer. 208 colorectal cancer patients (115 colon and 93 rectum) were studied; 54 were stage I, 62 stage II, 37 stage III and 55 stage IV. PIIIP serum levels were significantly higher in stage IV as compared to all other patient groups. The 5-year survival of stage I, stage II, stage III and stage IV patients were 87%, 88%, 32% and 20%, respectively. In the subgroup of stage I and stage II patients considered together, PIIIP (> 0.5 U/ml), but not CEA (> 5 microg/l) serum levels, were predictive for survival. Fibroblast growth was significantly inhibited, while PIIIP production was significantly enhanced, when these cells were conditioned with colorectal cancer homogenates obtained from patients with distant metastases, than from those without distant metastases. In conclusion, colorectal tumors, when metastatic, stimulate fibroblasts' PIIIP synthesis and the serum levels of this peptide might predict patients' outcome after radical surgery.

CD44-mediated oncogenic signaling and cytoskeleton activation during mammary tumor progression

CD44, a hyaluronan (HA) receptor, belongs to a family of transmembrane glycoproteins which exists as several isoforms. Cell surface expression of certain CD44 isoforms is closely correlated with the progression and prognosis of breast cancers. A number of angiogenic factors (e.g., VEGF and FGF-2) and matrix degrading enzymes (MMPs) are tightly complexed with CD44 isoforms, suggesting that they are involved in the onset of oncogenic signals required for breast tumor cell invasion and migration. Most importantly, interaction of extracellular matrix components (e.g., HA) with cells triggers the cytoplasmic domain of CD44 isoforms to bind its unique downstream effectors (e.g., the cytoskeletal protein ankyrin or various oncogenic signaling molecules-Tiam1, RhoA-activated ROK, c-Src kinase and p185HER2) and to coordinate intracellular signaling pathways (e.g., Rho/Ras signaling and receptor-linked/non-receptor-linked tyrosine kinase pathways), leading to a concomitant onset of multiple cellular functions (e.g., tumor cell growth, migration and invasion) and breast tumor progression.

Anti-metastatic efficacy and safety of MMI-166, a selective matrix metalloproteinase inhibitor

The anti-metastatic efficacy and safety of a newly-developed matrix metalloproteinase (MMP) inhibitor were examined. MMI-166, a N-sulfonylamino acid derivative, inhibited the enzyme activity of MMP-2, 9, and 14 but not MMP-1, 3 or 7. Daily oral administration of MMI-166 resulted in potent inhibition of metastatic lung colonization of Lewis lung carcinoma injected via the tail vein and liver metastasis of C-1H human colon cancer implanted into the spleen at inhibition levels of 43% and 63%, respectively. Daily administration of MMI-166 also resulted in prolonged survival of mice given intraperitoneal implantation of Ma44 human lung cancer cells. The anti-metastatic activity of MMI-166 was as effective as that of other MMP inhibitors with broad inhibitory spectrum. MMI-166 did not affect in vitro tumor cell growth. Neither body weight losses nor hematotoxicity was observed during long-term treatment, indicating the safety of MMI-166 in mice. These results indicate that the selective MMP inhibitor MMI-166 has therapeutic potential as an anti-metastasis agent.