Primary high-grade myoepithelial carcinoma of the lung: A study of three cases illustrating frequent SMARCB1-deficiency and review of the literature

Primary myoepithelial carcinoma of the lung is exceptionally rare and, hence, remained poorly characterized. We present 3 tumors affecting 2 males and 1 female aged 60 to 84 years. Tumor size ranged from 4 to 10 cm. All presented as well circumscribed non-encapsulated peripheral solitary masses. One patient died postoperatively. The other two were lost to follow-up. Histologically, all tumors were high-grade with predominance of myxoid/chordoid (2) and rhabdoid (1) pattern. Immunohistochemistry (IHC) showed reactivity with vimentin, pankeratin, EMA and smooth muscle actin. Two tumors were SMARCB1-deficient (one with additional loss of SMARCA2 and PBRM1). RNA sequencing revealed no gene fusions. Review of reported cases (total: 16) showed that pulmonary myoepithelial carcinoma affects both sexes equally at a median age of 60 years (24-84), presents predominantly as peripheral masses (69%) in the lower lobes (66%) of smokers (70%) with a median size of 6 cm (1.5-13), and originates as high-grade de novo carcinoma. Forty percent of patients died of disease at a median of 12.5 months (0 to 62). Only 40% of patients were disease free at last follow-up (median, 9.5 months). Prominent lobulation and myxoid stroma were frequent histological features. Most tumors displayed variable combinations of epithelioid, spindle, plasmacytoid, clear, ovoid or round cells. Three of 6 tumors subjected to different RNA panels showed EWSR1 rearrangements (fused to PBX1, ZNF444 or to unknown partner). Two of 3 tumors lacking gene fusions were SMARCB1-deficient (both showed secondary EWSR1 FISH abnormalities due to 22q deletion). Primary pulmonary myoepithelial carcinoma is a rare aggressive malignancy that recapitulates its soft tissue and salivary counterpart. Exclusion of metastasis from other primaries is mandatory and can only be achieved by detailed clinical history and imaging.

A novel loss-of-function mutation in LACC1 underlies hereditary juvenile arthritis with extended intra-familial phenotypic heterogeneity

OBJECTIVE

To investigate phenotypic and molecular characteristics of a consanguineous family with autosomal-recessive, polyarticular, juvenile idiopathic arthritis (JIA) with extra-articular manifestations, including renal amyloidosis and Crohn's disease, associated with a novel homozygous truncating variant in LACC1.

METHODS

Whole exome sequencing (WES) or targeted Sanger verification were performed in 15 participants. LACC1 expression and cytokine array were analyzed in patient-derived and CRISPR/Cas9-generated LACC1-knockout macrophages (Mϕ).

RESULTS

A homozygous truncating variant (p.Glu348Ter) in LACC1 was identified in three affected and one asymptomatic family member, and predicted harmful by causing premature stop of the LACC1 protein sequences, and by absence from ethnically-matched controls and public variation databases. Expression studies in patient-derived macrophages (Mϕ) showed no endogenous p. Glu348Ter-LACC1 RNA transcription or protein expression, compatible with nonsense-mediated mRNA decay. WES analysis in the asymptomatic homozygous subject for p. Glu348Ter-LACC1 detected an exclusive heterozygous variant (p.Arg928Gln) in complement component C5. Further complement activity analysis suggested a protective role for the p. Arg928Gln-C5 variant as a phenotypic modifier of LACC1-associated disease. Finally, cytokine profile analysis indicated increased levels of pro-inflammatory cytokines in LACC1-disrupted as compared with wild-type Mϕ.

CONCLUSIONS

Our findings reinforce the role of LACC1 disruption in autosomal-recessive JIA, extend the clinical spectrum and intra-familial heterogeneity of the disease-associated phenotype, indicate a modulatory effect of complement factor C5 on phenotypic severity, and suggest an inhibitory role for wild-type LACC1 on pro-inflammatory pathways.

Three-step management of a newborn with a giant, highly vascularized, cervical teratoma: a case report

Background

A giant congenital cervical teratoma is often highly vascularized; thus, in addition to a life-threatening airway occlusion at birth it comprises a high risk for significant and lethal blood loss during resection. In the case presented, an endovascular embolization of the carotid artery that supplied a giant congenital cervical teratoma was done as part of a three-stage treatment soon after birth and contributed to an overall good outcome. Embolization in cases of cervical teratomas was not described previously.

Case presentation

We present a case of a preterm newborn from a Sephardic jewish origin with a giant, highly vascularized, congenital cervical teratoma that was managed successfully in three stages: (1) delivery by an ex utero intrapartum treatment procedure after extensive preoperative planning and followed by tracheostomy, (2) endovascular embolization of the carotid artery that supplied the tumor in order to decrease blood loss during resection, and (3) complete surgical resection. The parents were involved in all the ethical and medical decisions, starting just after the cervical mass was diagnosed prenatally.

Conclusion

The management of giant congenital cervical teratoma is often challenging from both a medical and ethical prospective. Meticulous perinatal planning and parents’ involvement is crucial. Endovascular embolization of the tumor feeding vessels can significantly improve the resection outcome and overall prognosis.

Clinically significant sub-clonality for common drivers can be detected in 26% of KRAS/EGFR mutated lung adenocarcinomas

Genetic sub-clonality has been described in multiple malignancies, however the presence of sub-clonality for major drivers in lung adenocarcinoma and its clinical significance is a subject under debate. Using molecular and morphometric approach, 347 lung adenocarcinoma samples were analyzed for KRAS and EGFR sub-clonality, which was further correlated with clinical and pathological variables.KRAS and EGFR mutations were identified in 100 (29%) and 82 (23%) cases, respectively. One hundred and forty four KRAS or EGFR positive cases were also available for morphometric analysis, among which 37 (26%) were defined as sub-clonal. The presence of sub-clonality was associated with shorter survival time (p=0.02). Interestingly, cases with sub-clonality were also associated with earlier disease stage (89% vs 66% stage I disease in sub-clonal vs clonal cases, respectively, p=0.01) and less lymph node involvement (8% vs 25% in sub-clonal vs clonal cases, respectively, p=0.02). Our findings demonstrate the presence of sub-clonality for mutations in common drivers in lung adenocarcinoma and link it both to earlier disease stage and to poor survival. These findings are in line with the different evolutionary models that can present with genetic sub-clonality.

Mutant KRAS Circulating Tumor DNA Is an Accurate Tool for Pancreatic Cancer Monitoring

BACKGROUND

Many new pancreatic cancer treatment combinations have been discovered in recent years, yet the prognosis of pancreatic ductal adenocarcinoma (PDAC) remains grim. The advent of new treatments highlights the need for better monitoring tools for treatment response, to allow a timely switch between different therapeutic regimens. Circulating tumor DNA (ctDNA) is a tool for cancer detection and characterization with growing clinical use. However, currently, ctDNA is not used for monitoring treatment response. The high prevalence of KRAS hotspot mutations in PDAC suggests that mutant KRAS can be an efficient ctDNA marker for PDAC monitoring.

SUBJECTS, MATERIALS, AND METHODS

Seventeen metastatic PDAC patients were recruited and serial plasma samples were collected. CtDNA was extracted from the plasma, and KRAS mutation analysis was performed using next-generation sequencing and correlated with serum CA19-9 levels, imaging, and survival.

RESULTS

Plasma KRAS mutations were detected in 5/17 (29.4%) patients. KRAS ctDNA detection was associated with shorter survival (8 vs. 37.5 months). Our results show that, in ctDNA positive patients, ctDNA is at least comparable to CA19-9 as a marker for monitoring treatment response. Furthermore, the rate of ctDNA change was inversely correlated with survival.

CONCLUSION

Our results confirm that mutant KRAS ctDNA detection in metastatic PDAC patients is a poor prognostic marker. Additionally, we were able to show that mutant KRAS ctDNA analysis can be used to monitor treatment response in PDAC patients and that ctDNA dynamics is associated with survival. We suggest that ctDNA analysis in metastatic PDAC patients is a readily available tool for disease monitoring.

IMPLICATIONS FOR PRACTICE

Avoiding futile chemotherapy in metastatic pancreatic ductal adenocarcinoma (PDAC) patients by monitoring response to treatment is of utmost importance. A novel biomarker for monitoring treatment response in PDAC, using mutant KRAS circulating tumor DNA (ctDNA), is proposed. Results, although limited by small sample numbers, suggest that ctDNA can be an effective marker for disease monitoring and that ctDNA level over time is a better predictor of survival than the dynamics of the commonly used biomarker CA19-9. Therefore, ctDNA analysis can be a useful tool for monitoring PDAC treatment response. These results should be further validated in larger sample numbers.

Characterization of Factors Affecting the Detection Limit of EGFR p.T790M in Circulating Tumor DNA

OBJECTIVE

Circulating tumor DNA is a promising noninvasive tool for cancer monitoring. One of the challenges in applying this tool is the detection of low-frequency mutations. The detection limit of these mutations varies between different molecular methods. The aim of this study is to characterize the factors affecting the limit of detection for epidermal growth factor receptor p.T790M mutation in circulating tumor DNA of patients with lung adenocarcinoma.

METHODS

DNA was extracted from plasma samples of 102 patients. For sequencing the DNA, we used 2 different next-generation sequencing-based platforms: Ion Torrent Personal Genome Machine (56 cases) and Roche/454 (46 cases). Serially diluted synthetic DNA samples carrying the p.T790M mutation were sequenced using the Ion Torrent Personal Genome Machine for validation. Limit of detection was determined through the analysis of non-hot-spot nonreference reads, which were regarded as sequencing artifacts.

RESULTS

The frequency of the non-hot-spot nonreference reads was higher in Ion Torrent Personal Genome Machine compared to Roche/454 (0.07% ± 0.08% and 0.03% ± 0.06%, respectively, P < .001). We found that different base type substitutions occur with different frequency. Since the base substitution leading to p.T790M mutation is C>T transition, its frequency was used to determine the limit of detection for the assay. Based on the C>T non-hot-spot nonreference allele frequency, we found that the limit of detection is 0.18% in Ion Torrent Personal Genome Machine and 0.1% in Roche/454. Based on these values, 48% and 56% of the cases were positive for T790M mutation in Ion Torrent Personal Genome Machine and Roche/454 groups, respectively. Agreement between duplicates was 76% in Ion Torrent Personal Genome Machine and 72% in Roche/454. Using serially diluted synthetic DNA samples carrying the p.T790M mutation, we could identify mutations with allele frequency of 0.18% or more using the Ion Torrent Personal Genome Machine, supporting our approach to determine the detection limit.

CONCLUSION

Both the sequencing platform and the specific nucleotide change affect the limit of detection and should therefore be determined in the validation process of new assays.

The Iron-Klotho-VDR Axis Is a Major Determinant of Proximal Convoluted Tubule Injury in Haptoglobin 2-2 Genotype Diabetic Nephropathy Patients and Mice

The haptoglobin (Hp) genotype (1-1 and 2-2) is a major determinant of nephropathy progression in diabetes mellitus patients. Hp 2-2 diabetic mice have impaired Hb clearance and increased iron deposits and oxidative stress in the proximal tubules (PCT), leading to increased renal injury. However, the precise mechanism of the PCT injury in diabetic nephropathy (DN) remains elusive. In the kidney, 1,25(OH)₂D3 suppresses the inflammatory response to renal tubular injury and requires normal renal expression of the α-klotho protein. In this study, we set out to test the hypothesis that the increased renal iron deposits in the PCT of Hp 2-2 DN affect the α-klotho-vitamin D receptor (VDR) axis and thereby exacerbates the PCT injury generated by the iron deposits. Immunohistochemical analysis of human and mouse kidney biopsies along with western blot analysis showed that the increased iron deposits in the PCT of the Hp 2-2 genotype were accompanied with significantly decreased α-klotho and VDR renal expression but significantly increased 1-α-hydroxylase renal expression. In conclusion, the iron-klotho-VDR axis is a major player in the mechanism contributing to iron-mediated PCT injury in diabetic Hp 2-2 mice and patients. Targeting this axis may open the way for new ideas regarding the pathogenesis and treatment of DN.

Risk for molecular contamination of tissue samples evaluated for targeted anti-cancer therapy

With the increasing usage of sensitive PCR technology for pharmacogenetics, cross contamination becomes a significant concern. Researchers employed techniques which basically include replacing laboratory equipment after each sample preparation; however, there are no recommended guidelines. In the present work we wanted to evaluate the risk of cross contamination during tissue processing using the routine precaution measures. Twenty-one surgical samples of lung adenocarcinoma were used, of which 7 contained EGFR exon 19 mutation, 7 contained EGFR exon 21 mutation (p.L858R) and 7 were EGFR wild-type. The samples were ordered by alternating the mutation group to maximize the potential for cross contamination and underwent tissue sectioning and de-paraffinization. The entire process was performed using the same tools. Following DNA extraction all samples underwent PCR amplification and were scrutinized for small fractions of EGFR mutation using deep sequencing with the Ion torrent PGM technology. Twenty samples yielded results. The fraction of mutated copies was 41 ± 23% (range 11–66) for the cases with known exon 19 mutation and 48±24% (range 0–65) for the cases with known exon 21 mutations. No in-frame exon 19 deletion mutations were identified in the wild-type (WT) and exon 21 groups. The fraction of EGFR exon 21 (codon 858) mutations was 0.018±0.014% (range 0–0.05%) in the WT and exon 19 groups, which was not statistically different than the background sequencing artifact noise for the same base-pair alteration (p = 0.21). Our results suggest that standard precautions are sufficient for molecular pathology diagnosis of surgical samples and are not associated with increased risk of cross contamination.

Subclonality for BRAF Mutation in Papillary Thyroid Carcinoma Is Associated With Earlier Disease Stage

CONTEXT

The presence of driver mutations only in a subset of tumor cells within a single lesion, defined as subclonality, is being appreciated as a clinically significant factor. BRAF mutation is the most common driver mutation in papillary thyroid carcinoma (PTC). There are conflicting data in the literature regarding the presence of BRAF mutation subclonality in PTC and its clinical significance.

OBJECTIVE

The purpose of the present study was to use a molecular and morphometric approach to determine BRAF clonality status and its clinical-pathological correlates.

DESIGN

Fifty-nine cases of PTC were studied. DNA extracted from the tumors underwent deep sequencing to determine the percentage of BRAF mutant allele copies. Additionally, we used computerized morphometry to determine the fraction of tumor cells in each sample. Using both variables, we were able to determine the presence or absence of subclonality for BRAF mutation, which was further correlated with clinical, pathological, and prognostic data.

RESULTS

BRAF mutation was found in 49 (83%) cases. The average percentage of tumor cells and of BRAF mutant alleles in the samples were 68.1 ± 9.8 and 26 ± 6.7, respectively. Based on the molecular and morphometric analysis, 11 (24%) cases were found to be subclonal for BRAF mutation. Tumors with subclonal BRAF mutations were significantly smaller compared to tumors with clonal mutation (0.82 ± 0.38 cm vs 1.37 ± 0.57 cm, P = .005) and were less likely to have lymph node metastasis (0% vs 32%, P = .03).

CONCLUSIONS

In PTC, subclonality for BRAF mutation is associated with earlier stage. Molecular-morphometric analysis of PTC can provide clonality information with potential clinical significance.

Angiosarcoma arising in association with vascular Dacron grafts and orthopedic joint prostheses: clinicopathologic, immunohistochemical, and molecular study

Angiosarcoma may rarely arise near an inert foreign body material including vascular grafts and metal joint prostheses. Sixteen such cases have been reported since 1972 but mostly in the radiologic or surgical literature without detailed histologic or molecular analyses. We herein describe the clinicopathologic and molecular features of 2 new cases and reanalyzed 3 previously reported cases of angiosarcoma that developed in association with Dacron grafts for vascular repair (n=3) or related to orthopedic metal prostheses for joint replacement (n=2). All patients were men aged 50 to 84 years (median, 71 years). Mean time to development of angiosarcoma was 9 years (range, 4.6-17 years). Symptoms were recurrent bleeding/loosening of prosthesis for suspected infection (in the joint prosthesis cases) and fatigue, weight loss, and abdominal symptoms in the Dacron-associated cases. Four patients died of disease within 1 to 24 months (mean, 8 months). One patient was alive after radical surgery, radiochemotherapy, and embolization of pulmonary metastases (17 months). Histologically, all tumors were high-grade epithelioid neoplasms with a predominant solid growth pattern and variable vasoformation. All tumors expressed CD31, ERG, FLI-1, and variably pancytokeratin (diffuse in 3 cases), but none expressed D2-40, MDM2, or CDK4. Fluorescence in situ hybridization analysis revealed no MDM2 or CDK4 alterations. MYC was expressed in all cases, but only 1 case was MYC amplified by fluorescence in situ hybridization. Angiosarcomas are exceedingly rare fatal complications of long-standing metal and Dacron prostheses. Awareness of their morphology and frequent cytokeratin expression is necessary to avoid misdiagnosis as metastatic carcinoma. Limited awareness of their existence explains delayed clinical diagnosis in most of cases. Absence of MDM2/CDK4 alterations underlines their distinction from intimal-type sarcomas.

Early histological findings quantified by histomorphometry allow prediction of clinical phenotypes in Crohn's colitis patients

OBJECTIVE

To evaluate the histomorphometric features of early colonic biopsies from patients with Crohn's disease (CD) and their relationship to clinical phenotypes. The clinical course of Crohn's disease is variable and relevant for treatment selection. Early aggressive treatment may change the course of disease but should be balanced by safety considerations. Currently, prediction of disease course is suboptimal.

STUDY DESIGN

Colonic biopsies from CD colitis patients with different phenotypes were analyzed using histomorphometry. The quantitative results were used to predict postbiopsy clinical phenotypes and outcomes. Data analysis was performed using statistical and Neural Network models.

RESULTS

Univariate analysis revealed differences between the phenotypes in the number of inflammatory cells (p = 0.003), lymphocytic aggregates (p = 0.005) and optical density of mature and young collagen (p = 0.008 and p = 0.01, respectively). Multivariate analysis allowed for differentiation between the clinical phenotypes and prediction of surgery, with good sensitivity and specificity. A neural network model predicted clinical phenotypes with an accuracy of 94%. CONCLUSIQN:.To our knowledge this is the first study that applied histomorphometry on early biopsies in order to predict the clinical phenotypes in Crohn's colitis. Measurements allowed differentiation and prediction of clinical phenotypes and outcomes such as surgery. This approach, in combination with other known predictors, may increase the ability to classify and predict the clinical course of CD colitis, thus improving patient management. Prospective validation using larger cohorts is needed.

Normal colon tissue and colon carcinoma show no difference in heparanase promoter methylation

INTRODUCTION

Heparanase, the sole heparan sulfate degrading enzyme, has a role in cellular invasion. Accordingly, a large number of studies have demonstrated an association between heparanase expression and tumor stage and patients' prognosis. In colon carcinoma, heparanase shows increased expression in tumor compared to normal tissue and its expression correlates with the presence of metastasis. One of the regulatory mechanisms of heparanase expression is de-methylation on its promoter. In the present study we evaluated the role of heparanase promoter methylation in colon carcinoma.

MATERIAL AND METHODS

Analysis of heparanase promoter methylation was done on 32 samples of colon carcinoma as well as 30 samples of normal colonic mucosa. DNA was extracted from FFPE tissue and subjected to bisulfite conversion. The relative fraction of methylated and unmethylated DNA was evaluated using quantitative real-time PCR.

RESULTS

The fraction of methylated DNA was 1 ± 3.4% in the colon carcinoma group, and 2.5 ± 3.3% in the normal colon group (P=0.11). Only one case in the normal group and one case in the tumor group showed more than 10% methylation in the heparanase promoter.

CONCLUSION

We did not find any significant difference in heparanase promoter methylation between colon carcinoma and normal colonic mucosa, suggesting that heparanase overexpression in colon carcinoma is mediated by other mechanisms.

The incidence and prognostic value of HER2 overexpression and cyclin D1 expression in patients with gastric or gastroesophageal junction adenocarcinoma in Israel

Human epidermal growth factor 2 (HER2) positivity rates for gastric or gastroesophageal junction (GEJ) adenocarcinoma have been reported at 15-25%. Cyclin D1 (BCL1) is a non-specific proliferative marker. The prognostic significance of HER2 and cyclin D1 is inconclusive, with contradictory data. The aim of this study was to evaluate the incidence of HER2 overexpression in gastric or GEJ patients. The presence of a possible correlation between HER2 status and cyclin D1 staining was assessed; both were evaluated as prognostic markers for survival. The clinical data and histological specimens of 150 consecutive patients diagnosed with gastric or GEJ adenocarcinoma, and treated at our hospital from June 2005 to March 2009, were analyzed. Pathological specimens were immunohistochemically stained for HER2. Immunoreactivity was determined according to the scoring system for gastric carcinoma. Cyclin D1 immunoreactivity was also tested. The results demonstrated that HER2 was positive in 14/150 (9.3%) patients. HER2-positive (HER2(+)) and HER2-negative (HER2(-)) patients did not differ significantly with regard to other clinicopathological parameters. In a multivariate analysis, HER2 positivity was revealed to be a poor prognosis variable (P=0.046; 95% CI, 1.03-3.58). In patients with non-metastatic disease, median survival was 59 months for HER2(-) and 42 months for HER2+ patients, but this difference was not significant. In patients with metastatic disease, median survival was 9.5 months and 2.5 months for HER2(-) and HER2+ patients, respectively (P=0.041). Cyclin D1 was not idemonstrated to be a prognostic factor and was not associated with HER2 overexpression. The rate of positive HER2 status in the current group of unselected patients with gastric and GEJ adenocarcinoma was relatively low compared with that observed in the literature. Nevertheless, HER2 positivity was associated with a poor prognosis.

LNA-based PCR clamping enrichment assay for the identification of KRAS mutations

INTRODUCTION

KRAS mutations in colon carcinomas are associated with lack of response to anti-EGFR monoclonal antibody treatment. Therefore, patients must undergo genetic testing to be eligible for treatment. Several methods for KRAS mutation analysis exist, but many are not sensitive enough to detect a mutation in samples with low fraction of malignant cells. In the present study, we developed a KRAS mutations detection method that is both simple and sensitive.

METHODS

Using a locked nucleic acid (LNA) containing oligonucleotide, we developed a PCR clamping method that preferentially amplifies the mutated over wild type KRAS. We evaluated the sensitivity of this method using serial dilutions of plasmids containing wild-type and mutated KRAS fragments. Additionally, KRAS mutation status was evaluated on 60 archived tissue samples of colon carcinoma, and compared to direct sequencing and high resolution melting (HRM) methods.

RESULTS

The PCR clamping method could detect as little as 1% mutated DNA in the sample analyzed. Of the 29 KRAS mutations identified by the PCR clamping method, only 23 (79%) were identified by standard direct sequencing. The results of PCR clamping correlated with HRM results.

CONCLUSIONS

LNA based PCR clamping method is a simple and highly sensitive method for the detection of KRAS mutations.

Heparanase induces signal transducer and activator of transcription (STAT) protein phosphorylation: preclinical and clinical significance in head and neck cancer

Activity of heparanase is implicated strongly in dissemination of metastatic tumor cells and cells of the immune system. In addition, heparanase enhances the phosphorylation of selected signaling molecules, including SRC and EGFR, in a manner that requires secretion but not enzymatic activity of heparanase and is mediated by its C-terminal domain. Clinically, heparanase staining is associated with larger tumors and increased EGFR phosphorylation in head and neck carcinoma. We hypothesized that signal transducer and activator of transcription (STAT) proteins mediate the protumorigenic function of heparanase downstream of the EGFR. We provide evidence that heparanase enhances the phosphorylation of STAT3 and STAT5b but not STAT5a. Moreover, enhanced proliferation of heparanase transfected cells was attenuated by STAT3 and STAT5b siRNA, but not STAT5a or STAT1 siRNA. Clinically, STAT3 phosphorylation was associated with head and neck cancer progression, EGFR phosphorylation, and heparanase expression and cellular localization. Notably, cytoplasmic rather than nuclear phospho-STAT3 correlated with increased tumor size (T-stage; p = 0.007), number of metastatic neck lymph nodes (p = 0.05), and reduced survival of patients (p = 0.04).

The involvement of immune semaphorins and neuropilin-1 in lupus nephritis

Background and objectives: Neuropilin-1 (NP-1), a functional vascular endothelial growth factor (VEGF) receptor, is important in the priming of resting T cells and contributes to the development of peripheral tolerance. Semaphorins, a family of axon guidance molecules, has been found to be involved in regulating the immune system.

The aim of this study was to explore the involvement of NP-1 and semaphorins in lupus glomerulonephritis (LGN).

Methods: Twelve kidney biopsies from LGN patients and five normal biopsies were examined in this study. In addition, eight biopsies from patients with primary nephropathy and proteinuria were included serving as a disease control group. Biopsies were stained with anti-VEGF, NP-1, and semaphorins. The Image Pro-Plus software was used to measure the intensity and extent of staining. The correlation with clinico-pathological parameters was evaluated.

Results: VEGF expression was slightly higher in LGN. NP-1 and semaphorins were stained with significantly higher intensity in LGN when compared with both the normal and the disease control groups. NP-1 deposits were found only in damaged glomerulus areas and positively correlated with clinico-pathological parameters of renal disease (a statistical trend). However, the semaphorins were found in inverse correlations.

Discussion: Being present in normal and slightly increased in diseased glomeruli, VEGF is considered protective during inflammation. Increased NP-1 expression in LGN may intensify the possible protective effect of VEGF, thereby preventing endothelial damage. However, one should consider the possibility that increased NP-1 expression is harmful and could play a role in the damage of LGN. NP-1 is suggested to be a reliable marker differentiating focal versus diffuse LGN. Semaphorin 3A can serve as a histological marker for tubular damage. The altered ability of kidneys to secrete semaphorins during advanced renal damage may in part explain its inverse correlation with renal function. Further work is needed in order to better understand the role of NP-1 and semaphorins in LGN.

P27/SKP-2 histochemical profile is relevant to malignant salivary gland tumors (MST) histogenesis and tumor grade

Malignant salivary gland tumors (MST) represent over more than 24 distinct morphological subtypes. Most high grade tumors arise from the excretory duct portion of the salivary gland apparatus; the remainder from the intercalated duct portion. Altered p27/skp-2 expression has been associated with tumor aggressiveness and histologic differentiation. In our study, we analyzed p27/skp-2 expression proteins on series of malignant salivary gland tumors in order to assess their value as a histogenetic marker, which is relevant to tumor grade. 61 MST cases were segregated by proposed histogenesis and immunohistochemistry was performed using antibodies directed against p27 and skp-2. MST of proposed intercalated duct origin (n=27) showed strong p27 expression (n=25/27; 93%) in the vast majority of cases and all cases weakly expressed skp-2. MST of proposed excretory duct origin (n=32) showed strong p27 expression (n=18/32; 56%) and moderately strong/strong skp-2 expression (n=18/32; 56%), respectively, in over half the cases. MST of intercalated duct origin showed evident p27/skp-2 inverse correlation. Differences in p27/skp-2 expression among the MST subtypes correlated with histogenesis and tumor grade, which reinforces the notion that tumor behavior is relevant to the portion of the salivary gland unit from which they arise. MST of proposed intercalated duct origin strongly expressed p27, and not skp-2, unlike MST of proposed excretory duct origin. The immunohistochemical profile of high grade mucoepidermoid carcinoma was distinct from its low/intermediate grade counterparts, suggesting a separate identity. These results may influence future decision making when formulating workable MST categorization schemes. Further studies on a larger series of MST are warranted in order to support the value of our findings.

Gene expression differences between colon and rectum tumors

PURPOSE

Colorectal cancer studies typically include both colon and rectum tumors as a common entity, though this assumption is controversial and only minor differences have been reported at the molecular and epidemiologic level. We conducted a molecular study based on gene expression data of tumors from colon and rectum to assess the degree of similarity between these cancer sites at transcriptomic level.

EXPERIMENTAL DESIGN

A pooled analysis of 460 colon tumors and 100 rectum tumors from four data sets belonging to three independent studies was conducted. Microsatellite instable tumors were excluded as these are known to have a different expression profile and have a preferential proximal colon location. Expression differences were assessed with linear models, and significant genes were identified using adjustment for multiple comparisons.

RESULTS

Minor differences at a gene expression level were found between tumors arising in the proximal colon, distal colon, or rectum. Only several HOX genes were found to be associated with tumor location. More differences were found between proximal and distal colon than between distal colon and rectum.

CONCLUSIONS

Microsatellite stable colorectal cancers do not show major transcriptomic differences for tumors arising in the colon or rectum. The small but consistent differences observed are largely driven by the HOX genes. These results may have important implications in the design and interpretation of studies in colorectal cancer.

Prognostic value of heparanase expression and cellular localization in oral cancer

BACKGROUND

Metastases formation depends on the ability of tumor cells to invade basement membranes in a process involving enzymes capable of degrading extracellular matrix components.

METHODS

We examined the expression of heparanase in oral carcinomas and correlated its staining extent, intensity, and cellular localization with patients' outcome.

RESULTS

Quantitative real-time polymerase chain reaction (PCR) revealed over 4-fold increase in heparanase levels in oral carcinomas compared to adjacent normal tissue. Normal oral epithelium was found negative for heparanase, while all oral carcinomas stained positively for heparanase. Heparanase staining was associated with Ki67 staining, a measure of cell proliferation. Notably, whereas cytoplasmic localization of heparanase was associated with high-grade carcinomas, nuclear localization of the enzyme was found primarily in low-grade, well-differentiated tumors, and in all oral verrucous carcinomas.

CONCLUSION

Expression level and cellular localization of heparanase could serve as an important diagnostic marker in patients with oral cancer.

Oral cancer, cigarette smoke and mitochondrial 18kDa translocator protein (TSPO) - In vitro, in vivo, salivary analysis

Oral cancer features high rates of mortality and morbidity, and is in dire need for new approaches. In the present study we analyzed 18 kDa translocator protein (TSPO) expression in oral (tongue) cancer tumors by immunohistochemistry. We also assayed TSPO binding in human tongue cancer cell lines and in the cellular fraction of saliva from tongue cancer patients, heavy cigarette smokers, and non-smoking healthy people as controls. Concurrently, TSPO protein levels, cell viability, mitochondrial membrane potential (Deltapsi(m)), and general protein levels were analyzed. TSPO expression could be significantly enhanced in oral cancer tumors, compared to unaffected adjacent tissue. We also found that five-year survival probability dropped from 65% in patients with TSPO negative tumors to 7% in patients with highly expressed TSPO (p<0.001). TSPO binding capacity was also pronounced in the human oral cancer cell lines SCC-25 and SCC-15 (3133+/-643 fmol/mg protein and 6956+/-549 fmol/mg protein, respectively). Binding decreased by 56% and 72%, in the SCC-25 and SCC-15 cell lines, respectively (p<0.05) following CS exposure in cell culture. In the cellular fraction of saliva of heavy smokers TSPO binding was lower than in non-smokers (by 53%, p<0.05). Also the cellular fraction of saliva exposed to CS in vitro showed decreased TSPO binding compared to unexposed saliva (by 30%, p<0.001). Interestingly, oral cancer patients also displayed significantly lower TSPO binding in the cellular fraction of saliva compared to healthy controls (by 40%, p<0.01). Our results suggest that low TSPO binding found in the cellular fraction of saliva may depend on genetic background as well as result from exposure to CS. We suggest that this may be related to a predisposition for occurrence of oral cancer.

Heparanase expression by Barrett's epithelium and during esophageal carcinoma progression

Enzymatic activity responsible for the cleavage of heparan sulfate, commonly known as heparanase, is abundant in tumor-derived cells. Heparanase cleaves heparan sulfate side chains, presumably at sites of low sulfation, thus facilitating structural alterations of the extracellular matrix and basement membrane underlying epithelial and endothelial cells. Traditionally, heparanase activity was correlated with the metastatic potential of tumor-derived cells, attributed to enhanced cell dissemination as a consequence of heparan sulfate cleavage and remodeling of the extracellular matrix barrier. More recently, heparanase upregulation was documented in an increasing number of human carcinomas and hematological malignancies, correlating with increased tumor metastasis, vascular density, and shorter post-operative survival of cancer patients. Although heparanase upregulation and its pro-malignant features are well documented, the instance of its induction in the course of tumor development was less investigated. Here, we used immunohistochemical analysis to investigate heparanase expression in normal esophagus, Barrett's esophagus without dysplasia, Barrett's esophagus with low-grade dysplasia, Barrett's esophagus with high-grade dysplasia, and adenocarcinoma of the esophagus. We report that heparanase expression is already induced in Barrett's epithelium without dysplasia, and is further increased during progression through distinct pathological stages, namely, low-grade dysplasia, high-grade dysplasia, and adenocarcinoma. Notably, heparanase induction correlated with increased cell proliferation index revealed by Ki-67 staining. These findings suggest that heparanase function is not limited to the process of tumor metastasis, but rather is engaged at the early stages of esophagus carcinoma initiation and progression.

The expression and prognostic significance of Cks1 in salivary cancer

Cks1 is an essential factor in facilitating Skp2-dependent degradation of p27, but its role in salivary malignancies is unknown. Expression of cyclin-dependent kinase subunit 1 (Cks1) was examined in 64 salivary malignancies, compared with p27, S-phase kinase protein 2 (Skp2), Ki-67, p53, and TDT-mediated dutp-biotin nick end labeling (TUNEL) expression, and with THE patient's clinical and pathological parameters. Cks1 expression was markedly increased in 30 patients (47%) and strongly correlated with increased expression of Skp2, Ki-67, p53, and TUNEL, but inversely with p27 levels. High expression of Cks1 WAS strongly associated with lymph node metastases and poor prognosis and survival. Cks1 alterations may have a significant biological role in the pathogenesis of salivary cancer.

The salivary tip of the p53 mutagenesis iceberg: novel insights

Salivary malignancies are rare, heterogeneous, unpredictable in their clinical behavior and seldom studied. This study focused on examining the expression of mutated p53, the most prevalent mutated gene related to human cancer, in a rather large cohort of salivary malignancies (n = 70) and for a prolonged period (20 years). P53 was found to be a most powerful predictor for poor survival and more so when the tumor concurrently expressed TUNEL and heparanase markers, dramatically dropping the survival probability of the patients to 0! Survival probability at 6 years for patients with tumors stained negatively vs. positively for p53, TUNEL and heparanase was 100% vs. 49% while at 18 years this probability dropped to 67% vs. 0%, respectively (p = 0.023). Significant correlation rates were found between age and poor survival, age and p53, and p53 and other co-existing malignancies. These findings support mutated p53 as a prognostic predictor and a pivotal player in salivary carcinogenesis. Significantly more extensive therapy applied to salivary p53-positive patients did not improve mortality rate, questioning the justification for such extensive therapy and emphasizing the need to understand p53, TUNEL and heparanase biological pathways and develop additional therapeutic tools for fighting salivary cancer.

p27 and salivary cancer

This study examined p27 expression in a cohort of salivary malignancies (n = 74) for a prolonged period (20 years). Reduction of p27 expression was found to be a most powerful predictor for poor survival and more so when the tumor concurrently expressed high levels of p53, TUNEL and heparanase markers, dramatically dropping the patient survival probability to 0! While no patient whose tumor-staining profile included: p27 > 50%, p53 = 0, TUNEL = 0 and heparanase = 0, died of the disease during the 20-year follow up, the median of survival of the group with p27 0, TUNEL > 0 and heparanase > 0 was only 39 months. The survival probabilities of these two groups at 5 years were 100 and 50%, respectively, and at 20 years they were 100 and 0%, respectively (P = 0.05). Significant p27 reduction also resulted in significantly larger tumor size (T value), higher spread of neck metastasis and extra capsular spread and in more advanced disease (higher stage). Significant correlation rates were found between age and poor survival, age and reduced p27 expression, and reduced p27 expression and other general co-existing malignancies, indicating p27 reduction as part of a general phenomenon-age related mutagenesis. Significantly more extensive therapy applied to patients with salivary reduced-p27 tumors could not prevent the rise in mortality rate, questioning the justification for extensive therapy which is naturally accompanied by higher morbidity. Additional therapeutic tools for fighting salivary cancer, possibly based on the new understanding of the p27, p53, TUNEL and heparanase carcinogenic network, are necessary.

Skp2 and salivary cancer

Salivary malignancies are rare, heterogeneous, unpredictable in clinical behavior and seldom studied. Skp2 expression was examined in salivary malignancies (n = 75) for a prolonged period (20 years). In 40/75 (53%) cases Skp2 expression rate (staining level) was < or =4% while in the remainder (47%) it was >4%. Correlation between enhanced Skp2 and enhanced p53 staining levels was significant (p = 0.042), as were correlation rates between enhanced Skp2 and reduced p27 staining levels (p = 0.01) and enhanced Skp2 and enhanced TUNEL staining levels (p = 0.008). Survival probability rates dropped when Skp2 expression increased. Median patient survival for reduced-stained-tumor patients (< or =4%) was 143 months and significantly lower, 49 months (p = 0.016), for enhanced-stained-tumor patients (>4%). Survival probability at 5 years was 82% for the former group (< or =4%) and 47% for the latter (>4%). At 20 years, survival dropped to 35% and 18% respectively (p = 0.016). More extensive and aggressive therapy did not reduce mortality in patients with enhanced Skp2-expressing tumors. Significant correlations between poor survival and significantly altered expression rates of Skp2, p27, p53, TUNEL and heparanase in salivary malignancies, suggest a biological role in salivary cancer pathogenesis for these 5 markers. The findings may be used for prognostic and follow-up purposes.

Ki67 and salivary cancer

We examined Ki67 expression in salivary malignancies of 75 patients with a follow-up period of up to 20 years. Correlations between enhanced Ki67 and enhanced p53 and TUNEL and heparanase staining levels were significant. Median survival for reduced-stained-tumor patients (< or = 5%) was 163 months, dropping significantly to 39 months (p = 0.0005) for enhanced stained tumors (> 5%); 5 year survival probability was 93% and 33%, respectively, 45% and 16%, respectively, (p = 0.0005) at 20 years. Significant correlation between poor survival and concurrently altered expression rates of Ki67 and p53, p27 Skp2, TUNEL and heparanase in the salivary malignancies indicates a biological role in salivary cancer pathogenesis.

Heparanase is overexpressed in lung cancer and correlates inversely with patient survival

BACKGROUND

Heparanase is an endo-beta-D-glucuronidase that is capable of cleaving heparan sulfate (HS) side chains at a limited number of sites, yielding HS fragments of still appreciable size (approximately 5-7 kDa). Heparanase activity has been detected frequently in several cell types and tissues. Heparanase activity correlates with the metastatic potential of tumor-derived cells, a correlation that has been attributed to enhanced cell dissemination as a consequence of HS cleavage and remodeling of the extracellular matrix barrier.

METHODS

In this study, the authors examined heparanase expression in 114 patients with lung cancer by means of immunohistochemistry and correlated clinical-pathologic data with heparanase immunostaining and cellular localization.

RESULTS

Heparanase was overexpressed in 75% of the study patients. Heparanase expression was correlated with lung cancer lymph node status and metastasis classification (P = .04 and P = .01, respectively) and was correlated inversely with patient survival (P = .007). It is noteworthy that this adverse effect depended largely on the cellular localization of heparanase. Thus, whereas cytoplasmic staining of heparanase is associated with a poor prognosis, nuclear heparanase predicts a favorable outcome for patients with lung cancer.

CONCLUSIONS

The current findings suggest that heparanase expression and cellular localization are decisive for lung cancer patients' prognosis, most likely because of heparanase-mediated tumor cell dissemination by blood and lymph vessels.

TUNEL as a tumor marker of tongue cancer

Squamous cell carcinoma (SCC) of the tongue has an increasing incidence, a high morbidity rate and a 50% 5-year mortality rate. We analyzed the rate of apoptosis using TDT-mediated dUTP-biotin nick end-labeling (TUNEL), p53 and heparanase in 73 patients with tongue cancer by immonohistochemistry, and tested data for correlation with survival, tumor size, grade and metastasis. TUNEL staining was strong in 54% of the tumors; the remainder lacked staining, as did all healthy control tissues. Significant correlations were found between TUNEL staining level and p53 expression rates (p=0.016) and between TUNEL and heparanase (p=0.039). Moreover, while the cumulative 5-year survival probability for tumors not stained for TUNEL and p53 was 63%, but dropped to 34% with TUNEL staining; for lack of TUNEL and heparanase (=0), 5-year survival rate was 50%, while staining presence (>0) reduced survival to 34%. TUNEL joins other biomarkers in indicating prognosis of understanding pathogenesis of tongue cancer.

Over-expression of Skp2 is associated with resistance to preoperative doxorubicin-based chemotherapy in primary breast cancer

INTRODUCTION

Preoperative chemotherapy is often used in patients with locally advanced breast cancer. However, commonly used clinical and pathological parameters are poor predictors of response to this type of therapy. Recent studies have suggested that altered regulation of the cell cycle in cancer may be involved in resistance to chemotherapy. Over-expression of the ubiquitin ligase Skp2 results in loss of the cell cycle inhibitor p27Kip1 and is associated with poor prognosis in early breast cancer. The purpose of the present study was to examine the role of these proteins as predictors of clinical outcome and response to chemotherapy in locally advanced breast cancer.

METHODS

The expression levels of Skp2 and p27Kip1 were determined by immunohistochemistry both before and after preoperative chemotherapy in 40 patients with locally advanced breast cancer. All patients were treated with cyclophosphamide/doxorubicin (adriamycin)/5-fluorouracil (CAF) and some patients received additional treatment with docetaxel. Expression data were compared with patients' clinical and pathological features, clinical outcome, and response to chemotherapy.

RESULTS

Skp2 expression before preoperative chemotherapy was inversely related to p27Kip1 levels, tumor grade, and expression of estrogen and progesterone receptors. Both Skp2 and p27Kip1 were found to be accurate prognostic markers for disease-free and overall survival. High preoperative expression of Skp2 was associated with resistance to CAF therapy in 94% of patients (P < 0.0001) but not with resistance to docetaxel.

CONCLUSION

Skp2 expression may be a useful marker for predicting response to doxorubicin-based preoperative chemotherapy and clinical outcome in patients with locally advanced breast cancer.

Heparanase up-regulation in tongue cancer: tissue and saliva analysis

BACKGROUND

Heparanase up-regulation has been correlated with reduced postoperative survival in various cancers.

METHODS

Heparanase expression was analyzed in 60 consenting tongue (mobile) cancer patients by means of immunohistochemistry. Heparanase levels were also analyzed in the saliva of both healthy controls and tongue cancer patients using a novel heparanase enzyme-linked immunosorbent assay method.

RESULTS

Heparanase staining was positive (>0) in 92% and negative (=0) in 8% of the tumors and staining intensity correlated with tumor size and tumor stage. Moreover, the survival probability of patients negative for heparanase (=0) at 60 months was 100%, compared with only 41% for patients positive for heparanase (>0), suggesting that heparanase may serve as a prognostic factor for this malignancy and an attractive target for anticancer drug development. Heparanase was detected in the saliva of healthy controls and the mean concentration was determined as 119 +/- 37 pg/mL. Importantly, a nearly 3-fold increase of heparanase levels was detected in saliva collected from tongue cancer patients (334 +/- 69 pg/mL), a difference that is statistically highly significant (P = .004).

CONCLUSIONS

These findings support heparanase up-regulation in tongue cancer and raise the possibility of using this simple test as a diagnostic tool to monitor tongue cancer progression and response to treatment.

Regulation of the cell cycle inhibitor p27 and its ubiquitin ligase Skp2 in differentiation of human embryonic stem cells

Embryonic stem cells combine the features of robust proliferation with precise differentiation capacity. p27 is a cell cycle inhibitor that is involved in the regulation of proliferation and differentiation in many developing tissues. Recent studies in murine embryonic stem cells have suggested that p27 is involved in the progression of normal differentiation programs in these cells. However, the expression and regulation of p27 and its role in the differentiation of human embryonic stem cells (hESc) has not been previously explored. Herein we show that p27 expression was low in undifferentiated hESc, but increased markedly in differentiated cells. The expression of Skp2, the ubiquitin ligase that targets p27 for degradation, was inversely related to p27 expression. Moreover, embryoid bodies (EBs) with low p27 expression and high Skp2/p27 ratio showed poorer differentiation than those with high p27 expression. Modulation of Skp2 expression is mainly regulated by its rate of degradation. In contrast to somatic cells, which have high levels of Skp2 mainly in S and G2/M, in undifferentiated hESc Skp2 levels were also high in G1. These results point to a potentially important role for p27 regulation in hESc.

Downregulation of Sef, an inhibitor of receptor tyrosine kinase signaling, is common to a variety of human carcinomas

Carcinomas are tumors of epithelial origin accounting for over 80% of all human malignancies. A substantial body of evidence implicates oncogenic signaling by receptor tyrosine kinases (RTKs) in carcinoma development. Here we investigated the expression of Sef, a novel inhibitor of RTK signaling, in normal human epithelial tissues and derived malignancies. Human Sef (hSef) was highly expressed in normal epithelial cells of breast, prostate, thyroid gland and the ovarian surface. By comparison, substantial downregulation of hSef expression was observed in the majority of tumors originating from these epithelia. Among 186 primary carcinomas surveyed by RNA in situ hybridization, hSef expression was undetectable in 116 cases including 72/99 (73%) breast, 11/16 (69%) thyroid, 16/31 (52%) prostate and 17/40 (43%) ovarian carcinomas. Moderate reduction of expression was observed in 17/186, and marked reduction in 40/186 tumors. Only 13/186 cases including 12 low-grade and one intermediate grade tumor retained high hSef expression. The association of hSef downregulation and tumor progression was statistically significant (P<0.001). Functionally, ectopic expression of hSef suppressed proliferation of breast carcinoma cells, whereas inhibition of endogenous hSef expression accelerated fibroblast growth factor and epidermal growth factor-dependent proliferation of cervical carcinoma cells. The inhibitory effect of hSef on cell proliferation combined with consistent downregulation in human carcinoma indicates a tumor suppressor-like role for hSef, and implicates loss of hSef expression as a common mechanism in epithelial neoplasia.

TUNEL - an efficient prognosis predictor of salivary malignancies

Biological markers are necessary for predicting prognosis of salivary malignancies and better understanding the pathogenesis of salivary cancer. We analysed terminal deoxynucleotidyl transferase (TdT)-mediated biotinylated deoxyuridine-triphosphate (dUTP)-biotin nick-end labelling (TUNEL), p53 and Ki67 expression in 66 patients with malignant salivary tumours by immonohistochemistry, and correlated the data with survival, disease-free survival, tumour grade, stage, and local and distant metastasis. TUNEL efficiently predicted poor prognosis in salivary malignancies. The 5-year (5Y) survival probability dropped significantly with the level of TUNEL staining (from 83% in negatively stained tumours to 57 and 24% in TUNEL positively stained levels 1 and 2, respectively), (P=0.042). Extensive Ki67 staining (in addition to TUNEL) reduced the 5Y-survival rate even further and addition of positively stained p53 dropped the 5Y-survival rate to 0. The correlation rates between TUNEL and Ki67 was 58% (P=0.0001), and between TUNEL and p53 it was 50% (P=0.035). Concurrently, TUNEL correlated with metastasis, extracapsular spread, grade and stage. The correlation between TUNEL, p53 and Ki67 staining and survival probabilities, and the pathological grade, stage and metastasis spread of salivary malignancies makes this a highly effective tool in patient follow-up and prognosis.

Expression of the ubiquitin ligase subunit cyclin kinase subunit 1 and its relationship to S-phase kinase protein 2 and p27Kip1 in prostate cancer

PURPOSE

Loss of the cell cycle inhibitory protein p27Kip1 in cancer is associated with tumor aggressiveness and poor prognosis in the prostate. The decrease in p27(Kip1) results from increased proteasome dependent degradation, which is mediated by its specific ubiquitin ligase subunits S-phase kinase protein 2 and cyclin dependent kinase subunit 1. S-phase kinase protein 2 was found to be over expressed in aggressive prostate cancers but to our knowledge the role of cyclin dependent kinase subunit 1 in these cancers is unknown.

MATERIALS AND METHODS

The expression of cyclin dependent kinase subunit 1, S-phase kinase protein 2 and p27Kip1 was examined by immunohistochemistry in tissue sections from 45 patients with prostate cancer. The expression of cyclin dependent kinase subunit 1 was compared to that of S-phase kinase protein 2 and p27Kip1, and patient clinical and histological characteristics.

RESULTS

Cyclin dependent kinase subunit 1 expression was strongly associated with S-phase kinase protein 2 expression (r = 0.666, p = 0.001) and inversely with p27Kip1 expression (r = -0.737, p < 0.001). Cyclin dependent kinase subunit 1 over expression was associated with loss of tumor differentiation (r = 0.631, p = 0.001), high serum prostate specific antigen (r = 0.627, p < 0.001) and metastatic disease (p < 0.001).

CONCLUSIONS

These results suggest that cyclin dependent kinase subunit 1 is involved in p27Kip1 down-regulation and it may have an important causative role in the development of aggressive tumor behavior in prostate cancer.

Heparanase upregulation by colonic epithelium in inflammatory bowel disease

Heparanase is an endo-beta-D-glucuronidase capable of cleaving heparan sulfate (HS) side chains at a limited number of sites, yielding HS fragments of still appreciable size ( approximately 5-7 kDa). Heparanase activity has long been detected in a number of cell types and tissues. Importantly, heparanase activity correlated with the metastatic potential of tumor-derived cells, attributed to enhanced cell dissemination as a consequence of HS cleavage and remodeling of the extracellular matrix barrier. Similarly, heparanase activity was implicated in neovascularization, inflammation and autoimmunity, involving migration of vascular endothelial cells and activated cells of the immune system. The involvement of heparanase in inflammatory processes of the gastrointestinal tract has not been examined. Here, we utilized immunohistochemical analysis to investigate heparanase expression in acute and chronic inflammatory conditions. Heparanase expression was not detected in specimens derived from normal colon tissue. In contrast, strong heparanase staining was observed in Crohn's disease and ulcerative colitis, but not in infectious colitis. Interestingly, heparanase staining was primarily observed in epithelial rather than immune cells. Importantly, un-fractionated as well as low molecular weight heparin (enoxaparin), which exhibit a strong inhibitory activity towards heparanase, have proven efficacious in ulcerative colitis and Crohn's disease patients, suggesting that heparanase is actively involved in these pathologies and thus may be considered as a target for the development of anti-inflammatory therapies.

Heparanase expression in malignant salivary gland tumors inversely correlates with long-term survival

BACKGROUND

Upregulation of the endo-beta-D-glucuronidase, heparanase, was noted in an increasing number of human malignancies. Heparanase expression correlated with enhanced local and distant metastatic spread, increased vascular density, and reduced postoperative survival.

PATIENTS AND METHODS

We analyzed heparanase expression in 60 patients (aged 59 +/- 17 years) with malignant salivary tumors (39 males and 21 females) using immunohistochemistry. We applied antiheparanase antibody 733, which has previously been shown to preferentially recognize a 50-kDa active heparanase subunit over a 65-kDa latent enzyme. Thus, immunostaining can directly be correlated with enzymatic activity.

RESULTS

Heparanase staining was positive (> 0) in 70% of tumors (42 of 60 patients) and was negative (0) in the remaining 30% (18 patients). The cumulative survival of patients diagnosed as heparanase-negative (n = 18) at 300 months was 70% (95% confidence interval = 35-88). In contrast, the cumulative survival of patients diagnosed as heparanase-positive (n = 42) at 300 months was 0% (statistically significant difference, P = .035).

CONCLUSIONS

Heparanase expression levels inversely correlate with the survival rates of salivary gland cancer patients, clearly indicating that heparanase is a reliable prognostic factor for this malignancy and an attractive target for anticancer drug development.

Heparanase expression in nasopharyngeal carcinoma inversely correlates with patient survival

AIMS

To determine the expression and prognostic significance of heparanase in nasopharyngeal carcinoma (NPC).

METHODS

Immunohistochemistry was performed on formalin-fixed paraffin-embedded sections of 46 patients with NPC. Clinical and immunohistochemical data were correlated with gender, age, histological type, Epstein-Barr virus (EBV) status, stage and survival.

RESULTS

Heparanase immunoreactivity was found in 35% (16/46) of specimens. The cumulative survival of patients diagnosed as heparanase negative (n = 30) at 10 years was 70%. In contrast, the cumulative survival of patients diagnosed as heparanase positive (n = 16) at 10 years was 25%, differences that are highly statistically significant (P = 0.03). No significant correlations were found between heparanase immunoreactivity and gender, age, EBV status, tumour histology or tumour stage.

CONCLUSION

Heparanase expression is inversely correlated with survival of NPC patients, clearly indicating that heparanase is a reliable prognostic factor for this malignancy, and further supports the notion that heparanase is a valid target for the development of anti-cancer drugs.

Inhibition of basic leucine zipper transcription is a major mediator of atrial dilatation

OBJECTIVE

Atrial fibrillation is the most prevalent clinically significant cardiac arrhythmia. Atrial dilatation, a predictor of atrial fibrillation, is thought to result from increased ventricular pressure. However, the underlying molecular mechanisms responsible for atrial dilatation are largely unknown. Here we sought to examine whether the expression of a basic leucine zipper inhibitor protein, JDP2, in the heart is sufficient for the generation of atrial dilatation.

METHODS

A tetracycline-regulated transgene was used to express JDP2 specifically in the mouse heart. Mice hearts were dissected and subjected to Northern and Western analysis, or analyzed by ECG recording and echocardiography. Regulation of gene expression was studied using electromobility shift assays and luciferase gene reporter analysis.

RESULTS

Expression of JDP2 resulted in massive bi-atrial dilatation, defects in conduction, and a lethal phenotype. These effects were developmentally independent, acquired during adulthood, and were reversible upon abolishing of JDP2 expression. Connexin 40 and myosin light chain 2a expression were identified as potential target genes.

CONCLUSION

Expression of basic leucine zipper transcription inhibitors is sufficient to results in atrial dilatation. This dilatation is acquired postnatally and is reversible. Thus, basic leucine zipper transcription inhibitors may be a relevant therapeutic target for preventing atrial dilatation and atrial fibrillation.

Expression of cell cycle regulatory proteins in ovaries prophylactically removed from Jewish Ashkenazi BRCA1 and BRCA2 mutation carriers: Correlation with histopathology

OBJECTIVES

Prophylactic oophorectomy in Ashkenazi Jewish women with BRCA mutations represents a unique opportunity to search for premalignant changes in ovaries. Reports on the presence of dysplastic lesions in these ovaries are contradictory. Our aim was to study the expression of cell cycle regulatory proteins--p53, Skp2, p27, Ki67, Bcl2 and p16--in correlation with histopathological changes. p16(INK4A) was not studied before in prophylactically removed ovaries.

METHODS

Ninety-four ovaries from 50 Ashkenazi Jewish BRCA carriers were compared with 42 ovaries removed for reasons unrelated to cancer and with 16 ovarian carcinomas.

RESULTS

Three (6%) patients from the high-risk group had an occult carcinoma. A significant association was found between BRCA-positive expression and the presence of atypical changes in the superficial ovarian epithelium (P = 0.014) as well as the presence of epithelial cortical clefts (P = 0.042). Expression of p53 in cortical inclusions was significantly higher in the BRCA-positive cases than in the benign control group (P = 0.03). The high-risk and the benign control group did not differ significantly by the expression of p16, BCL2, Ki67, p27 and SKP2 (P > 0.05). However, both groups significantly differed from the carcinoma group (P < 0.0001). A significant positive correlation was found between the expression of Ki67, and the grade of atypia in the high-risk group (R = 0.3, P = 0.01) and in the benign control group (R = 0.5, P = 0.02).

CONCLUSIONS

BRCA mutation carriers had more atypical changes in the superficial epithelium (P = 0.014) and more epithelial cortical clefts (P = 0.042) compared to the benign control group. The histopathology changes were not supported by significantly altered expressions of the proteins used in our study. Additional molecular studies could contribute to the disclosure of precancerous ovarian lesions.

Pediatric nasopharyngeal carcinoma: better prognosis and increased c-Kit expression as compared to adults

INTRODUCTION

Nasopharyngeal carcinoma (NPC) in children is distinguishable from the adult form by its close association with Epstein-Barr virus (EBV) infection, a higher rate of undifferentiated histology, and a greater incidence of advanced locoregional disease.

PATIENTS AND METHODS

Sixteen NPC patients, < or =20 years of age were identified from our 1976-2001 tumor registry records. Clinical stage, treatment, recurrence, and survival were evaluated. Sections were stained by immunohistochemistry for p53, Bcl-2, Ki67, and c-Kit and by in situ hybridization for EBER. Obtained data were compared to 32 adult patients. All patients had undifferentiated or non-keratinizing NPC.

RESULTS

EBER was positive in 100% of children, compared to 90% of adults. Comparing children to adults, median Ki67 index was 49% and 30%, p53 positive tumors were 69% and 94%, positive Bcl-2 was 63% and 72%, and positive c-Kit was 88% and 28%, respectively.

CONCLUSION

No parameter had significant predictive values for survival, although c-Kit expression had a trend for better prognosis in the pediatric group. By univariate analysis of all 48 cases, positive c-Kit was associated with better survival (P = 0.029), largely due to the better survival of the pediatric group. By multivariate analysis, increased stage (P = 0.006) and older age (P = 0.044) correlated with worse prognosis.

Oropharyngeal cancer pathogenesis: Ubiquitin proteolytic, apoptotic and epidermal growth factor related pathways act in concert—first report

The current study was carried out to examine the clinical characteristics and survival-probability rates of 51 patients treated for oral (tongue) cancer and to correlate it with various tumor markers. The clinical data and survival probability rates were correlated with the immunohistological analysis of p27, Skp2, p53, Bcl-2, TUNEL (apoptotic rate) and c-erbB-2 markers. The 5-year survival-probability correlated with staging, grading and base of tongue location. An inverse relation between the expression of p27 and Skp2, p27 and grading, and a direct relation between Skp2 and grading were demonstrated. Concomitantly, significant correlations between low p27, high Skp2 and high TUNEL (apoptotic rate) expressions and between low p27 and high c-erbB-2 (Her2) expressions in the cancer lesions were demonstrated. The accumulated data may be employed in the future for a better understanding of the biology behind oral cancer and for developing better means of detection and treatment.

The expression of the ubiquitin ligase subunit Cks1 in human breast cancer

Introduction

Loss of the cell-cycle inhibitory protein p27^Kip1 is associated with a poor prognosis in breast cancer. The decrease in the levels of this protein is the result of increased proteasome-dependent degradation, mediated and rate-limited by its specific ubiquitin ligase subunits S-phase kinase protein 2 (Skp2) and cyclin-dependent kinase subunit 1 (Cks1). Skp2 was recently found to be overexpressed in breast cancers, but the role of Cks1 in these cancers is unknown. The present study was undertaken to examine the role of Cks1 expression in breast cancer and its relation to p27^Kip1 and Skp2 expression and to tumor aggressiveness.

Methods

The expressions of Cks1, Skp2, and p27^Kip1 were examined immunohistochemically on formalin-fixed, paraffin-wax-embedded tissue sections from 50 patients with breast cancer and by immunoblot analysis on breast cancer cell lines. The relation between Cks1 levels and patients' clinical and histological parameters were examined by Cox regression and the Kaplan–Meier method.

Results

The expression of Cks1 was strongly associated with Skp2 expression (r = 0.477; P = 0.001) and inversely with p27^Kip1 (r = -0.726; P < 0.0001). Overexpression of Cks1 was associated with loss of tumor differentiation, young age, lack of expression of estrogen receptors and of progesterone receptors, and decreased disease-free (P = 0.0007) and overall (P = 0.041) survival. In addition, Cks1 and Skp2 expression were increased by estradiol in estrogen-dependent cell lines but were down-regulated by tamoxifen.

Conclusion

These results suggest that Cks1 is involved in p27^Kip1 down-regulation and may have an important role in the development of aggressive tumor behavior in breast cancer.

Increased renal hypertrophy in diabetic mice genetically modified at the haptoglobin locus

BACKGROUND

The human haptoglobin (Hp) gene is polymorphic with two functional classes of alleles, denoted 1 and 2. We have demonstrated in three longitudinal studies and several cross-sectional studies that the Hp genotype is an independent risk factor for diabetic vascular disease. These studies have presented a compelling argument that diabetic individuals homozygous for the Hp 1 allele are at decreased risk of vascular complications as compared to diabetic individuals with the Hp 2 allele.

METHODS

The naturally occurring (wild type) mouse Hp is a class 1 Hp allele. We examined renal hypertrophy in wild-type mice, Hp knockout mice (Hp 0), and in mice with the Hp 2 allele (Hp 2) with and without diabetes.

RESULTS

In the absence of diabetes, we found that renal hypertrophy was significantly increased in Hp 0 mice and that this could be prevented with vitamin E. There was no difference between wild type and Hp 2 mice with regard to renal hypertrophy in the absence of diabetes. However, in the presence of diabetes, Hp 2 mice demonstrated a significant increase in renal hypertrophy as compared to wild-type mice.

CONCLUSIONS

These results support a direct linkage between diabetic vascular disease and the Hp genotype. These Hp-modified mice may serve as a platform on which to test a variety of pharmacological agents in order to decrease diabetic vascular disease.

Low-grade renal collecting duct carcinoma. A case report with histochemical, immunohistochemical, and ultrastructural study

We report a rare tumor called low-grade renal collecting duct carcinoma. Grossly, the tumor consisted of multiple cysts and solid white nodules, measuring 10 cm in diameter and occupying most of the renal parenchyma. Histologically, the tumor was characterized by well-differentiated tubules lined by eosinophilic cells without papillary projections, abundant predominantly extracellular mucin, minimal cellular atypia, no desmoplasia, and rare mitoses. This tumor occurs in collecting ducts and the tumor cells were positive for epithelial membrane antigen, high-molecular-weight keratin, CD15, and mitochondrial antibody and negative for CD10. Few cells stained weakly positive for ulex europaeus. Ultrastructural study showed a large number of mitochondria according to the eosinophilic cells seen in light microscopy.