Abstract 004: Pro-angiogenic Effects Of The Thrombospondin-1 Inhibitor Lskl In Preeclampsia Models

Introduction: Preeclampsia (PE) is characterized by high blood pressure, proteinuria and/or multi-organ damage, reaching 10% of all pregnancies globally. To date, no medication can treat PE. We recently identified an upregulation of the antiangiogenic protein Thrombospondin-1 (THBS1) in human and experimental PE. THBS1 is a main activator of latent TGF-β. We postulate that THBS1-mediated TGF-β activation can contribute to impair placental angiogenesis during PE. In this study, we aim to test the effects of LSKL, an inhibitor of TGF-β activation by THBS1, on angiogenesis in placentas of a mouse model of PE and in human placental endothelial cells exposed to PE-like conditions.

Methods: Heterozygous female mice overexpressing human angiotensinogen and renin (PE) or C57BL/6 (control) were treated with LSKL or control peptide SLLK (280 μM, sc) at gestational day (GD) 14.5 (n=3 pregnant mouse/group). Placentas (n=4-9/pregnancy) were collected at GD 18.5. Placental expressions of TGF-β1, β2, total/phospho SMAD2 were assessed by western blot and angiogenesis by immunohistochemistry. Endothelial cells were extracted by magnetic sorting from human placentas (n=4) of healthy pregnancies. Cells were treated with LSKL or SLLK (30 μM) under hypoxia (0.5% vs. 8% O 2 ) or thrombin (10 u/mL). THBS1 expression in cells was assessed by immunofluorescence. Cell angiogenesis was quantified by the number of closed tubes formed on matrigel (per 15,000 cells, 4h).

Results: LSKL treatment reduced the expression of TGF-β2 (P<0.01) and phospho-SMAD2 (P<0.05) and significantly improved angiogenesis (P<0.05) in placentas of PE mouse versus control. In cells, both thrombin (P<0.05) and hypoxia (P<0.05) significantly increased THBS1 expression. Thrombin (P<0.01) and hypoxia (P<0.05) significantly impaired cell angiogenesis on matrigel (P<0.01), which was prevented by LSKL treatment (P<0.01). LSKL similarly reduced TGB-β2 (p<0.05) and phospho-SMAD2 (P<0.05) expressions in endothelial cells under thrombin and hypoxia cell exposure.

Conclusion: Our results describe a significant pro-angiogenic effect of LSKL treatment by regulating THBS1 and TGF-β2 mechanisms in an experimental model of PE and in human placental endothelial cells exposed to PE-like conditions.

[Monocentric study on pharmaceuticals taken by patients to treat systemic sclerosis]

INTRODUCTION

Pharmaceutical prescription in systemic sclerosis is guided by national and international recommendations. This study's primary objective was to describe and analyze these prescriptions among patients of our cohort. We also aimed to assess drug compliance among our patients.

METHODS

This is a monocentric observational study on two cohorts of patients with systemic sclerosis; a primary cohort comprising ambulatory patients, who were prospectively included, with exhaustive prescription's data collection; and a secondary cohort included patients asked to fill in a self-questionnaire on treatment compliance.

RESULTS

The main cohort included 157 patients, including 31 cases of diffuse systemic sclerosis. A vasodilator drug for Raynaud's phenomenon was prescribed in 75 patients (47.9%) and a specific treatment for pulmonary arterial hypertension in 10 patients (6.4%). Immuno-modulators/immunosuppressants was prescribed in 62 patients (39.5%), who received prednisone (n=37, 23.6%), mycophenolate mofetil (n=14, 8.9%), hydroxychloroquine (n=12, 7.6%) and colchicine (n=22, 14%). Treatment for "gastro-intestinal tract involvement" was prescribed for 106 patients (67.5%) and treatment of a scleroderma renal crisis with an angiotensin-converting enzyme inhibitor for 6 patients (3.8%). Among the 42 patients in the secondary cohort, 21.4% reported a good compliance, mostly older patients (P=0.045) or those who had not experienced adverse events (P=0.009).

CONCLUSION

This study provides original real-life data illustrating the heterogeneity of prescription habits in systemic sclerosis. As previously reported, treatment compliance was insufficient.

Abstract P104: Activation of Endoplasmic Reticulum Stress and Thrombospondin-1 Anti-Angiogenic Mechanisms in Placentas of Hypertensive Mice

Background: Thrombospondin-1 (Thbs1) is an anti-angiogenic focal adhesion glycoprotein. It binds to receptors CD36, LRP1 and CD47 activating anti-proliferative and anti-migratory mechanisms. Pre-eclampsia (PE) is characterized by poor placenta perfusion and angiogenesis, which is stimulated by oxidant and endoplasmic reticulum (ER) stresses contributing to placental insufficiency. ER stress has also been linked to Thbs1 anti-angiogenic actions. However, whether this mechanism is active in PE is unclear. Our aim was to describe ER stress and Thbs1 regulation in placental tissues and endothelial cells in a genetic mice model of chronic maternal hypertension and superposed pre-eclampsia.

Methods and Results: Placentas (n=8/group) were collected at 18.5 gestational days from transgenic mice overexpressing human renin and angiotensinogen versus controls (C57BL/6). CD31+ endothelial cells were isolated from placental tissues by magnetic separation. ER stress proteins IRE1a and calreticulin (CLR), as well as Thbs1 and receptors expressions were measured by western blot in placental tissues. CLR and Thbs1 localization in endothelial cells was assessed by immunofluorescence. Data are presented as average±SD. Our results show that IRE1a expression was increased in placentas of hypertensive mice (54±24% P=.05) while CLR was not different. However, in endothelial cells, CLR was shown mobilized from the ER compartment towards the membrane in cells of hypertensive pregnancies or in those exposed to hypoxia. Thbs1 (122±51% P=.03) and receptors CD47 (51±21% P=.03) and LRP1 (58±25% P=.04) were more expressed in placentas of hypertensive pregnancies versus controls, while CD36 was not different. The treatment of endothelial cells of hypertensive pregnancies with a Thbs1 inhibitor, LSKL, has significantly enhanced their angiogenic capacity allowing cells to form closed tubes on matrigel in comparison with the lack of closed tubes in untreated cells.

Conclusion: Our results described an ER stress state and Thbs1 upregulation in placental tissue and endothelial cells of hypertensive pregnancy. Our findings suggest an important anti-angiogenic role of the Thbs1 mechanism in placentas of hypertensive mice.

[Three cases of Jaccoud's arthropathy during systemic sclerosis]

INTRODUCTION

Jaccoud's arthropathy (JA) is a chronic and non-erosive deforming arthropathy, usually affecting the hands. JA pathophysiology is poorly known but involves periarticular structures such as tendons and the joint capsule. JA is associated with various conditions including the connective tissue disease, especially systemic lupus erythematosis. JA has been rarely described and studied in systemic sclerosis.

CASE REPORTS

We report the clinical histories of 3 patients with systemic sclerosis (ScS) who developed JA. One patient had a systemic limited disease and the 2 others a cutaneous limited disease ; mean age of the patients was 79.3 years. Systemic sclerosis was diagnosed respectively 19, 1 and 21 years prior to the development of JA. One of the 3 patients had a past clinical history of discoid lupus. For 1 out of the 3 patients, JA appeared whereas the ScS was completely stable. The disease was still active in the 2 remaining patients, with concurrent pulmonary hypertension diagnosis. Deformities increased during years (Z thumbs, ulnar deviation), leading to mild to severe disability. No benefit from either prednisone (n=2) or a combination of prednisone and methotrexate (n=1) was obtained.

CONCLUSION

We described 3 cases of Jaccoud's arthropathy among our scleroderma cohort of 296 patients (1%). This arthropathy worsens hand functional disability. Its pathophysiology is unknown and optimal therapeutic approach remains to establish.

Cancer of the ampulla of Vater: chromosome 17p allelic loss is associated with poor prognosis

BACKGROUND

Cancer of the ampulla of Vater kills 60% of affected patients. Local spread of the tumour (T stage) is the only reliable prognostic factor. Nevertheless, any cancer stage includes long term survivors and patients dying from the disease. The molecular anomalies involved in this process have the potential to serve as additional prognostic markers.

AIM

To evaluate if allelic losses (LOH) of chromosomes 17p and 18q may be of prognostic value in multivariate survival analysis.

METHODS

We examined 53 ampullary cancers for chromosome 17p and 18q LOH using microsatellite markers and DNA from paraffin embedded tumours. All patients were treated by surgery alone (pancreaticoduodenectomy). Multivariate survival analysis included age, sex, tumour size, macroscopic appearance, grade of differentiation, T stage, lymph node metastasis, and chromosome 17p and 18q status.

RESULTS

Chromosome 17p and 18q LOH were detected in 28 (53%) and 18 (34%) cancers, respectively. Multivariate survival analysis indicated chromosome 17p status as an independent prognostic factor together with T stage. The five year survival for chromosome 17p retention and 17p loss was 80% and 7%, respectively. The risk of death from cancer within the five year follow up period for patients with cancers harbouring chromosome 17p LOH was 11 times higher than that of patients with cancers retaining chromosome 17p (p<0.0001), regardless of the tumour stage at diagnosis.

CONCLUSIONS

Chromosome 17p status is an independent prognostic factor among ampullary cancers at the same stage. The combined use of T stage and chromosome 17p status may help in deciding whether ampullary cancer patients require additional therapy other than surgery alone.

Chromosome 5 allelic losses are early events in tumours of the papilla of Vater and occur at sites similar to those of gastric cancer

During our studies of DNA fingerprinting of tumours of the pancreas and papilla (ampulla) of Vater, using arbitrarily primed polymerase chain reaction (AP-PCR), we noticed two bands showing a decreased intensity in six of ten ampullary tumours with respect to matched normal tissues. Those bands were both assigned to chromosome 5. Such a finding was somewhat in contrast with the reportedly low frequency of APC gene mutations in ampullary cancers, located at chromosome 5q21, and suggested that loci different from that of APC might be the target of chromosome 5 allelic losses (LOH) in these tumours. Therefore, we analysed chromosome 5 LOH in a panel of 27 ampullary tumours, including eight adenomas, four early- and 15 advanced-stage cancers, using 16 PCR-amplified CA microsatellite polymorphic markers spanning the entire chromosome. Nineteen cases (70%) showed LOH, and the interstitial deletions found in these tumours described two smallest common deleted regions, in which putative suppressor genes might reside. They were at 5q13.3-q14 and at 5q23-q31 respectively, which correspond to those found in gastric tumours. In addition, the presence of 5q LOH in six of eight adenomas and in three of four early-stage cancers suggests that such phenomena occur at early stages of neoplastic progression of the ampullary epithelium.

Molecular pathogenesis of sporadic duodenal cancer

Whether duodenal adenocarcinoma should be considered as a gastrointestinal or as a peripancreatic cancer is a matter of debate, as is the opportunity and type of treatment. We investigated 12 such cancers for the genetic anomalies involved in the pathogenesis of gastrointestinal malignancies, including (a) those occurring in common-type cancers - allelic losses at chromosomes 3p, 5q, 17p and 18q, and Ki-ras and p53 alterations; and (b) those characteristic of mutator-phenotype cancers - microsatellite instability and TGF-betaRII gene mutations. We found Ki-ras and p53 mutations in five (42%) and eight cancers (67%), respectively; chromosome 3p, 5q, 17p and 18q allelic losses in two of nine (22%), six of ten (60%), six of nine (67%) and three of ten (30%) informative cancers, respectively. Finally, three cancers (25%) showed widespread microsatellite instability and two of them had a TGF-betaRII gene mutation. Our data suggest that duodenal cancers may arise from either of the two known pathogenetic molecular pathways of gastric and colorectal cancers. The majority of our cases were highly aggressive cancers with frequent chromosomal changes and p53 mutations as observed in the common-type gastrointestinal malignancies, while widespread subtle alterations characteristic of mutator-phenotype cancers occurred in a minority, which also showed a favourable long-term outcome.

Molecular techniques in hematopathology

Molecular techniques have already earned a place in the management of hematologic disorders. The requests of clinical hematologists to Pathology include, besides the diagnosis, any additional information useful for prognosis and therapeutic choices, as well as expertise and technologies to follow-up patients. To fulfill these commitments, pathologists have been resorting to classical morphology, cytochemistry, immunocytochemistry, and have only recently come to include molecular genetic techniques. Most of the molecular methods of practical utility are based on the analysis of DNA. The DNA methodologies of routine applicability mainly include Southern blotting and polymerase chain reaction (PCR). Southern blotting recognizes major DNA rearrangements, whereas PCR-based methods allow to recognize both gross chromosomal modifications and fine gene alterations, including point mutations. PCR techniques may also be used for partially degraded DNA from formalin-fixed paraffin-embedded tissues. Here we will draw a brief overview of the role of molecular genetic techniques in the pathology practice for the diagnosis, prognosis and follow-up of neoplastic diseases, using examples from our experience.

Cancers of the papilla of vater: mutator phenotype is associated with good prognosis

Cancer of the papilla (ampulla) of Vater is an uncommon disease that kills 60% of affected patients. There is general agreement that local spread of the tumor (T stage) is the only significant and independent prognostic factor for this cancer, whereas the predictive value of tumor grade and lymph node metastases is controversial. The genetic anomalies involved in this process have the potential to serve as additional prognostic markers. We explored 25 ampullary cancers for the occurrence of instability at simple repeat DNA sequences (microsatellites) of the type seen in replication error phenotype (RER-positive) cancers. Ten microsatellites from five different chromosomes were amplified by PCR from both normal and cancer tissue DNA of the same patients. A tumor was defined as RER-positive when microsatellite instability was found in the majority (>/=6) of the loci analyzed. Five cancers (20%) showed a RER phenotype and were associated with long survival of patients (32-96 months), whereas RER-negative cancers had a significantly poorer prognosis (Mantel-Cox test; P = 0.0084), with a median actuarial survival of 17 months. We also report that three (12%) patients belonged to cancer-prone families and four (16%) were cancer-prone individuals.

APC gene mutations and allelic losses in sporadic ampullary tumours: evidence of genetic difference from tumours associated with familial adenomatous polyposis

We explored APC gene mutations and chromosome 5q21 allelic losses (5qLOH) in 18 neoplasms of the papilla of Vater, including 6 early-stage tumours (3 adenomas, 3 carcinomas) and 12 advanced-stage cancers. Eleven PCR-amplified polymorphic sequences were used to analyse 5qLOH. APC mutations were investigated both by an in vitro APC-protein truncation test and by single-strand conformation polymorphism analysis. Mutations in the Ki-ras, N-ras and p53 genes were also assessed. We found: 5qLOH in 8 of 16 cases (50%), including 1 adenoma, 3 early- and 4 advanced-stage cancers; APC mutations in 2 adenomas and 1 advanced-stage carcinoma; Ki- or N-ras mutations in 3 adenomas and 3 advanced-stage cancers; p53 mutations in 2 early-stage and 7 advanced-stage adenocarcinomas. Our results suggest that 5qLOH, APC mutations and ras mutations are present at early stages, whereas p53 inactivation is associated with progression of malignancy in a large proportion of cases. These data indicate that sporadic ampullary tumours differ from those occurring in familial adenomatous polyposis in the frequency (17% vs. 64%) as well as in the site of APC somatic mutations, suggesting a different molecular pathogenesis in the 2 conditions.

APC gene mutations and allelic losses in sporadic ampullary tumours: evidence of genetic difference from tumours associated with familial adenomatous polyposis

We explored APC gene mutations and chromosome 5q21 allelic losses (5qLOH) in 18 neoplasms of the papilla of Vater, including 6 early-stage tumours (3 adenomas, 3 carcinomas) and 12 advanced-stage cancers. Eleven PCR-amplified polymorphic sequences were used to analyse 5qLOH. APC mutations were investigated both by an in vitro APC-protein truncation test and by single-strand conformation polymorphism analysis. Mutations in the Ki-ras, N-ras and p53 genes were also assessed. We found: 5qLOH in 8 of 16 cases (50%), including 1 adenoma, 3 early- and 4 advanced-stage cancers; APC mutations in 2 adenomas and 1 advanced-stage carcinoma; Ki- or N-ras mutations in 3 adenomas and 3 advanced-stage cancers; p53 mutations in 2 early-stage and 7 advanced-stage adenocarcinomas. Our results suggest that 5qLOH, APC mutations and ras mutations are present at early stages, whereas p53 inactivation is associated with progression of malignancy in a large proportion of cases. These data indicate that sporadic ampullary tumours differ from those occurring in familial adenomatous polyposis in the frequency (17% vs. 64%) as well as in the site of APC somatic mutations, suggesting a different molecular pathogenesis in the 2 conditions.

Chromosome 7q allelic losses in pancreatic carcinoma

During our DNA fingerprinting studies of paired normal and pancreatic cancer tissues using arbitrarily primed PCR, we noticed a band showing an apparent homozygous deletion in a pancreatic cancer cell line and a decreased intensity in a number of primary cancers. That band was assigned to chromosome 7. Such information led us to analyze chromosome 7 loss of heterozygosity (LOH) in a panel of 12 cryostat-enriched primary pancreatic cancers and 2 pancreatic cancer cell lines, despite the reportedly low frequency of chromosome 7 LOH in xenograft-enriched pancreatic cancers. Seventeen PCR-amplified CA-microsatellite polymorphic sites were analyzed. One of the two cell lines and eight common-type cancers (including all five poorly differentiated and three of five moderately differentiated cancers) showed chromosome 7q LOH, whereas the two uncommon types of ductal cancer (one adenosquamous and one mucinous noncystic) scored negative. Our data suggest that chromosome 7q LOH is a frequent event (80%) in cryostat-enrichable common pancreatic ductal carcinomas, that is, those primarily of high cellularity. The chromosome 7q smallest common deleted region described by our cases was between 7q31.1 and 7q32.

HCV RNA detection in parotid gland biopsy in a patient with chronic hepatitis C virus liver disease

We report a case of a 75-year-old woman admitted to our Unit for chronic sialadenitis, characterized by histologic evidence of B and T lymphocyte infiltrate; laboratory and histologic tests revealed chronic hepatitis C, without autoimmune markers. We found hepatitis C virus (HCV) RNA in liver, in parotid gland, in saliva and in peripheral blood mononuclear cells, but not in serum. HCV RNA was detected by PCR technique. To our knowledge this is the first case of detection of HCV RNA in parotid gland. This finding raises the question about the relationship between sialadenitis and viral HCV infection.

Routine application of polymerase chain reaction in the diagnosis of monoclonality of B-cell lymphoid proliferations

We evaluated four polymerase chain reaction (PCR) methods for their efficiency in detecting monoclonality in a well-characterized panel of frozen and paraffin-embedded B-cell lymphoid proliferations. These approaches (referred to as FR3, FR3A, FR2, and FR1) are based on amplification of rearranged immunoglobulin heavy chain genes, using primers recognizing framework regions I, II, or III. FR3, FR3A and FR2 approaches reproducibly detected monoclonality in 51%, 72%, and 67% of DNAs from frozen lymphomas, respectively. No false-positives were observed. The combination of FR2 and FR3A methods raised the figure to 85%. Comparable results were obtained using paraffin-embedded lymphomas. Reproducibility of FR1 approach was unsatisfactory. The efficiency of all PCR approaches varied depending on lymphoma type. The highest detection rate was in small/intermediate cell and the lowest in centro-follicular lymphomas. Limiting dilution assays showed that PCR methods were able to detect monoclonal B-cell DNA representing 5% of nonlymphoid and 20% of polyclonal B-cell DNA. A diagnostic protocol may include quick and cost-effective PCR screening, particularly in cases of undetermined small cell lymphoid proliferations observed in fine needle aspirates or endoscopic biopsies. This would also reduce call-up of patients to obtain unfixed biopsies.

ras-family gene mutations in neoplasia of the ampulla of Vater

Mutations in the first and second exons of Ha-, Ki- and N-ras oncogenes were investigated in 17 epithelial tumors of the ampulla of Vater by single-strand conformation polymorphism analysis and direct sequencing of DNA fragments amplified by polymerase chain reaction. The panel included 12 intestinal-type adenocarcinomas, 3 villous adenomas, 1 papillary carcinoma and 1 neuroendocrine carcinoma. Six cases (35%) contained ras mutations, affecting codon 12 of Ki-ras in 2 adenomas and 3 carcinomas, and of N-ras in 1 adenoma. All mutations were found in adenomas and among cancers with adenomatous areas, whereas none of the cases lacking adenomatous areas contained mutations. This suggested that ampullary cancers represent heterogeneous diseases with respect to the presence or absence of adenomatous areas and, among those with adenomatous areas, with respect to the presence of activated ras genes. Ki-ras mutated cases included 3 of 4 tumors which mainly involved the intraduodenal bile duct, thus suggesting that a proportion of Ki-ras-mutated ampullary cancers might correspond to those originating from the epithelium of the bile duct component of the ampulla.