OP0236 RELEVANCE OF BIASED PAR2 INHIBITORS IN REDUCING INFLAMMATION AND CARTILAGE DEGRADATION IN IN VITRO AND IN VIVO MODELS OF RHEUMATOID ARTHRITIS

Background:

Protease-activated receptor-2 (PAR2) is a member of a family of G-protein-coupled receptors involved in multiple physiological mechanisms. Compelling evidences have unravelled the key roles of PAR2 in the pathology of both rheumatoid arthritis (RA) and osteoarthritis (OA)1. Indeed, in vitro, in vivo and ex vivo experiments showed that this receptor promotes inflammation, cartilage erosion (and subsequent bone degradation), and pain. However, the signalling pathways involved in these functions are not well understood2. This is of importance as some pathways can promote the pathogenesis3while others prevent it4. We developed a new series of small molecules as novel biased PAR2 inhibitors to treat rheumatic diseases.

Objectives:

To evaluate the efficacy and mechanism of action of new biased PAR2 inhibitors on cartilage erosion and inflammation.

Methods:

The potency of compounds to inhibit human PAR2 signalling was evaluated in vitro by FLIPR calcium assay in HEK293 cells. The same assay was used to determine their selectivity over human PAR1 and PAR4 as well as murine versions of PAR2. The effect of several PAR2 inhibitors on 9 signalling pathways (Gi2, GoB, Gz, Gq, G13, G14, G15, B arrestin 2, EPAC) was evaluated by the BRET-based bioSens-All™ technology. In vitro anti-hypertrophic effect was determined by measuring the mRNA level of type II collagen, aggrecan and MMP13 in rat chondrocytes after IL1β stimulation. In vitro anti-inflammatory effect was determined by measuring the secretion of IL6, IL8, IL1β, TNFα and IFNγ by human monocytes. In vivo, the pharmacodynamic of our small molecules was assessed after intravenous and oral administration. Therapeutic efficacy of a compound was then evaluated in a collagen-induced arthritis model in DBA1/J mice. In this model, measures of the arthritis index score, body weight, plasma level of TNFα, IL6, IL8 and IL1β and histological evaluation of cartilage erosion were performed.

Results:

Our new series of small molecules are potent PAR2 inhibitors (IC50<1nM in calcium assay) with some selectivity over PAR1 and PAR4. Our compounds significantly inhibited PAR2 mediated recruitment of Gz, Gq, G13, G14 and G15. However, surprisingly, these small molecules had no effect on B arrestin 2, EPAC, Gi2 and GoB demonstrating that they are biased inhibitors. The effect of our compounds on PAR2 signalling was clearly different from 3 already existing PAR2 inhibitors described in the literature (I-117, AZ3451 and P2pal-18s). We compared the in vitro anti-hypertrophic effect on chondrocyte and anti-inflammatory effect on monocytes of these compounds to determine the importance of PAR2 signalling pathways in these cellular functions. In vivo, our small molecules had good bioavailability after oral administration of 10mg/kg in mice (clearance = 0.038L/h/kg; T½ = 9.9h; AUC= 162564 ng.h/mL; Cmax = 9005 ng/mL). The in vivo therapeutic efficacy of a biased PAR2 inhibitor in a model of collagen-induced arthritis will be presented.

Conclusion:

Our results show the potency of biased PAR2 inhibitors to reduce both the inflammation and cartilage erosion in rheumatoid arthritis. They confirm the huge potential of PAR2 as a therapeutic target and unravel the relevance of biased antagonism of this receptor to treat rheumatic diseases.

References:

[1]McCulloch et al., Frontiers in Endocrinology, 2018;2Hollenberg et al., British Journal of Pharmacology, 2014;3Sharma et al., Genes and Immunity, 2015;4Rayees et al., Cell Reports, 2019

Disclosure of Interests:

Thibaut Brugat Employee of: Domain Therapeutics, Baptiste Rugeri Employee of: Domain Therapeutics, Gaël Hommet Employee of: Domain Therapeutics, Alexia Dumont Employee of: Domain Therapeutics, Luc Baron Employee of: Domain Therapeutics, Célia Halter Employee of: Domain Therapeutics, Meriem Sémache Employee of: Domain Therapeutics, Arturo Mancini Employee of: Domain Therapeutics, Camille Amalric Employee of: Domain Therapeutics, Marie Giambelluco Employee of: Domain Therapeutics, Nathalie Lenne Employee of: Domain Therapeutics, Marjorie Sidhoum Employee of: Domain Therapeutics, Christel Franchet Employee of: Domain Therapeutics, Stanislas Mayer Employee of: Domain Therapeutics, Xavier Leroy Employee of: Domain Therapeutics, Stephan Schann Employee of: Domain Therapeutics

[Evolution of the number of incident cases, stage and first treatments for prostate cancer in France between 2001 and 2016]

INTRODUCTION

No studies of French hospital registries for prostate cancer (PCa) have been published since the 2012 USPSTF recommendations.

MATERIAL

This is a multicenter cohort study based on hospital data of prostate biopsies (PB) in 3 health centers between 2001 and 2016. The main objective is to describe the evolution of incident cases of PCa. The secondary objectives are to describe the number of cases per stage of PCa and the distribution of the first treatments.

RESULTS

In total, 11,491 PB series diagnosed 5927 cases of PCa. The median age was 67 [61-73] years and the median PSA was 7.8 [5.5-13] ng/mL. The number of cases increased until 2006 before decreasing from 2006 to 2013 and then stabilizing from 2013 to 2016. The proportion of incident cases was: (1) for the stable metastatic stage around 8 [7-10]%, (2) for cases with PSA<10 ng/mL increasing from 46% to 75% in 2010 down to 64% in 2016, (3) for the grade 1 group decreasing from 59% to 33 % between 2011 and 2016. The proportion of active surveillance treatment for low-risk cancers increased from 5 to 60% and surgery decreased from 73 to 33%.

CONCLUSION

The evolution of the incident cases showed a decrease from 2006 to 2013 and a stability until 2016. The number of cases with PSA<10 ng/mL decreased since 2010 and the proportion of the options of treatment by surveillance increased strongly to the detriment of the surgery for low risks.

LEVEL OF EVIDENCE

3.

[Pathology findings after radical prostatectomy for prostate cancer in patients eligible for active surveillance: Contribution of multiparametric MRI to treatment decision]

OBJECTIVES

To analyze, in patients with prostate cancer (PC) potentially eligible for active surveillance (AS), whether multiparametric-MRI (mp-MRI) predicts presence of clinically significant cancer on radical prostatectomy (RP) specimen.

METHODS

We identified 77 men with PC eligible for AS (PSA≤15ng/mL, stage≤T2a, Gleason score≤6, up to 3 positive cores, maximal cancer core length≤5mm) who underwent RP between 01/2008 and 08/2015. All patients had prebiopsy mp-MRI followed by systematic±targeted biopsies. For each patient, the likelihood of the presence of cancer on mp-MRI was assigned using Likert scale (1 to 5). The predictive factors for the presence of significant cancer on RP specimen (Gleason score≥7 and/or tumoral maximal diameter>10mm) were evaluated using logistic regression.

RESULTS

Median age was 61 and median PSA was 6.7ng/mL. Overall, 49 (64%) patients had a positive mp-MRI (score≥3). Clinically significant cancer on RP specimen was found in 45 (58%) patients (69% in MRI-positive patients vs 39% in MRI-negative patients). In multivariate analysis, a positive MRI was a predictive factor for the presence of significant cancer on the surgical specimen (OR=3.0; CI95% [1.01-8.88]; P=0.04), as was age (OR=1.17; CI95% [1.05-1.31]; P=0.004) and PSAD (OR=1.10; CI95% [1.01-1.20]; P=0.02).

CONCLUSION

Mp-MRI is a useful exam for selecting patients eligible for AS even if the situation remains unclear after prostate biopsies including targeted biopsies. Upon confirmation by further studies, mp-MRI should be considered as an independent criterion before entering an AS program.

LEVEL OF EVIDENCE

4.

Leydig cell tumor of the testis with azoospermia and elevated delta4 androstenedione: case report

Background

Secreting interstitial cell (Leydig cell) tumors are rare. In adults, the clinical picture and steroid levels are variable.

Case presentation

This paper presents a case of left testicular tumor, showing azoospermia with normal serum level of total testosterone, collapsed FSH and LH, and high delta4 androstenedione. Histopathological investigation revealed a Leydig cell tumor. TESE allowed spermatozoa extraction and freezing. Testicular histology found hypospermatogenesis and germ-cell aplasia with interstitial fibrosis. Surgical resection of the tumor resulted in normalization of gonadotropins and fall in serum delta4 androstenedione to subnormal levels in the postoperative period confirming that the tumor was secreting delta4 androstenedione. It was hypothesized that high delta4 androstenedione resulted in intra tumoral 17 β-HSD overtaken by delta4 androstenedione or that 17 β-HSD activity in the tumor was different from that of normal Leydig cells. Three months after surgery sperm analysis found a complete recovery of spermatogenesis. A spontaneous pregnancy occurred 3 months after surgery and a girl was born.

Conclusions

In this case, the diagnosis of testicular Leydig cell tumor secreting delta4 androstenedione was made in a context of azoospermia.

[Osteoid osteoma of zygomatic bone: Case report and literature review]

INTRODUCTION

Osteoid osteoma is a benign osseous tumor affecting mainly young men. Although it develops essentially in long bones, some cases occurring in face, mainly in mandible, were related. To our knowledge, only one single case was described in zygomatic bone.

OBSERVATION

A 71-year-old man consulted for a right periorbital pain evolving since months with night recrudescence. The pain was not relieved by standard analgesics. Clinical examination was strictly normal. CT scan showed a low-density bone lesion surrounded by a peripheral osseocondensation line within the body of the right zygoma with intense uptake at bone scintigraphy. The patient benefited from surgical excision of the lesion. Pain stopped immediately. Histological examination assessed an osteoid osteoma.

DISCUSSION

Zygomatic localization and late occurrence are rare concerning osteoid osteomas. Many ways of management have been reported but surgical excision remains the gold standard.

Low-grade Tubular Myxoid Renal Tumors: A Clinicopathological Study of 3 Cases

We report 3 cases of a new renal cell tumor entity with a review of the literature. These 3 cases were retrieved from the files of this institution from 1991 to 2002. The clinical data and all histologic slides were reviewed and an immunohistochemical study was performed. Patients were all females. Tumors were almost similar with well-defined margins. Tumor architecture was tubular and focally fusiform with an abundant myxoid stroma. Tumor cells were low cuboidal, slightly eosinophilic with low nuclear grade. Immunohistochemistry was in favor of a distal nephron differentiation. All patients were healthy after surgery. We describe 3 cases of a new clinicopathological entity entitled low-grade tubular myxoid renal tumor with a benign clinical course.

Histopathological classification of refractory chronic rhinosinusitis with nasal polyps

OBJECTIVE

To delineate the histopathological characteristics of nasal mucosa in refractory chronic rhinosinusitis with nasal polyps (CRSwNP) in order to demonstrate subtypes of nasal polyps and their potential relation with lower airway comorbidity.

STUDY DESIGN

Clinical- and pathological-based cross-sectional study Methods: Nasal polyp specimens were prospectively collected from patients with refractory CRSwNP referred to our institution for endoscopic sinus surgery. Oral and topical steroids were stopped 1 month before surgery. The pathological analysis was conducted by 2 independent reviewers with light microscopy on Hematoxylin-Eosin-Saffron stained slides. Each observer fulfilled a standardized protocol with cell count and stromal characterization on the most representative field. Mean grading scores were established. Morphological aspects were compared with the cell distribution and the clinical conditions.

RESULTS

Among 36 patients, three subtypes of nasal polyps were depicted: eosinophilic edematous (64%), fibrous (9%) and intermediate with mixed edematous and collagen stromal structure (27%). Basement membrane thickening and seromucous gland hyperplasia were observed in the fibrosis sub-type (p<0.03). Eosinophilic mucosal infiltrate was significantly increased (p=0.026) in patients with concomitant pulmonary disease (n=21). Nasal polyp distribution was not influenced by asthma, allergy, previous surgery and smoking.

CONCLUSION

Our 3-subtype classification of refractory CRSwNP in Caucasian population shows a predominant edematous structure whatever the clinical conditions may have been. Eosinophilia as a major factor of adaptive immune response in nasal inflammation is a feature of concomitant pulmonary disease. Further studies concerning mucosal remodelling and outcome assessment after sinus surgery are required to evaluate the impact of our classification on a daily basis.

Identification of novel TMPRSS2:ERG mechanisms in prostate cancer metastasis: involvement of MMP9 and PLXNA2

Prostate cancer (PCa) is one of the major public health problems in Western countries. Recently, the TMPRSS2:ERG gene fusion, which results in the aberrant expression of the transcription factor ERG, has been shown to be the most common gene rearrangement in PCa. Previous studies have determined the contributions of this fusion in PCa disease initiation and/or progression in vitro and in vivo. In this study on TMPRSS2:ERG regulation in PCa, we used an androgen receptor and TMPRSS2:ERG fusion double-negative PCa cell model: PC3c. In three cell clones with different TMPRSS2:ERG expression levels, ectopic expression of the fusion resulted in significant induction of cell migration and invasion in a dose-dependent manner. In agreement with this phenotype, high-throughput microarray analysis revealed that a set of genes, functionally associated with cell motility and invasiveness, were deregulated in a dose-dependent manner in TMPRSS2:ERG-expressing cells. Importantly, we identified increased MMP9 (Metalloproteinase 9) and PLXNA2 (Plexin A2) expression in TMPRSS2:ERG-positive PCa samples, and their expression levels were significantly correlated with ERG expression in a PCa cohort. In line with these findings, there was evidence that TMPRSS2:ERG directly and positively regulates MMP9 and PLXNA2 expression in PC3c cells. Moreover, PLXNA2 upregulation contributed to TMPRSS2:ERG-mediated enhancements of PC3c cell migration and invasion. Furthermore, and importantly, PLXNA2 expression was upregulated in metastatic PCa tumors compared with localized primary PCa tumors. This study provides novel insights into the role of the TMPRSS2:ERG fusion in PCa metastasis.

Efficiency of 5-ALA mediated photodynamic therapy on hypoxic prostate cancer: a preclinical study on the Dunning R3327-AT2 rat tumor model

OBJECTIVES

To evaluate photodynamic therapy (PDT) using 5-ALA-induced protoporphyrin IX (PPIX) in an in vivo hypoxic tumor model and its monitoring using MRI.

MATERIAL AND METHODS

Dunning R3327-AT2 tumors were grafted in the neck of Copenhagen rats. PDT using 150 mg 5-ALA/kg i.v. was performed by focal interstitial illumination of the photosensitized tumor (λ=633 nm; fluence=100 J/cm(2)). MRI at baseline and 2 days after treatment (T1, T2 and dynamic gadolinium enhanced sequences) were performed. Necrosis volumes were determined on post-procedure MRI. Tumors were resected 2 days post-PDT and obtained necrosis was determined histopathologically. Intra-tumoral PPIX distribution was evaluated using confocal microscopy and tissue porphyrin quantification.

RESULTS

Twenty rats were treated divided into three groups: continuous (n=7), fractionated illumination (n=7), and a control group receiving only light or only ALA or neither (n=6). Baseline MRI confirmed the hypoxic character of tumors. Necrosis volumes determined on posttreatment MRI were not reproducible and presented with important geometric and volumetric variability. Average necrosis volumes of 0.39 cc (0-0.874 cc) in the continuous group, 0.24 cc (0.107-0.436 cc) in the fractionated group and 0.012 cc (0-0.071 cc) in the control group were observed. Intra-tumoral PPIX distribution was heterogeneous and PPIX quantification revealed low intra-tumoral concentration.

CONCLUSION

Necrosis volumes induced by 5-ALA-mediated PDT were highly variable and non reproducible, probably because of lack of intra-tissular oxygen. Photosensitizer was poorly represented inside the tumor and its distribution was heterogeneous. Our study suggests that 5-ALA-mediated PDT might not be the best management option for hypoxic prostatic adenocarcinoma.

[Small renal masses: 10 years of treatment in a tertiary referral center in cancer research]

OBJECTIVES

To analyze the impact of preoperative clinical data that could influence the undertaking of small renal masses (size<4cm) and to direct patients towards surgery or observance or radiofrequency.

PATIENTS AND METHODS

From January 2000 to December 2010, 253 small renal masses were included in a retrospective study. Renal masses less than 3cm were compared to the 3 to 4cm masses. Clinical data, pathological data and follow-up was noted prospectively on the database and we analyzed it according to the treatment done (surgery, radiofrequency or observation).

RESULTS

Surgical treatment, radiofrequency and observation were performed for 214 (86.4%), 15 (5.9%), and 24 (9.5%) patients respectively. The treatments of the patients differed in the two groups (<3cm vs. 3-4cm) and the appeal to radiofrequency and observation was more frequent for elder patients (>65years old) and for those whom performance status (ECOG status) greater or equal to 1. Cancer specific survival was not statistically different for the two groups (average: 87.5% after 5years, mean 33months follow-up, P=0.7). Independent risk factors of recurrence were Fuhrman grade, synchronous tumors, noddles invasion and metastatic progression. Positive surgical margins were not a risk factor of recurrence (P=0.6).

CONCLUSION

Age and performance status are the two main clinical data, which influence the treatment for patients with small renal masses. Radiofrequency and observation were undertaken more regularly for elder and altered ones. The use of scales as Charlson Index or Lee scale could help to choose more easily according to global morbidity and mortality.

[Elements of completeness and results of the first year of registration of the "Registre général des cancers de Lille et de sa région"]

BACKGROUND

In 2005, following the first cancer plan of the national health authorities, a general cancer registry was established in northern France, in a territory designated as a "zone in proximity to the city of Lille" (ZPL). The aim of the present work was to evaluate the completeness of the registry's first year of incident cancer registration (2005) and to compare the observed cancer incidence in the "ZPL" with the estimated incidence in France.

METHODS

Completeness was assessed using the average number of sources per case, the percentage of histological verification and a method of independent case ascertainment (mortality/incidence ratio). A direct standardization on the world population was used to calculate the ZPL/France ratios of standardized incidence rates. Analyses were conducted for 21 cancer sites.

RESULTS

In 2005, 3635 cases of invasive cancer were recorded by the registry. The average number of sources per case was 2.7 and histological proof was available for 91.4% of cases. Mortality/incidence ratios showed satisfactory completeness of the data for men for most cancer sites. For women however, for cancer sites for which the number of cases was low, data will have to be confirmed during the subsequent years of observation. A lack of completeness was found for cutaneous melanoma. In men, an overincidence was identified for cancers of lip-mouth-pharynx, larynx, esophagus, lung, liver, bladder, kidney and colon-rectum. In women, an overincidence has been identified for cancers of lip-mouth-pharynx, liver, bladder, colon-rectum, corpus uteri and ovaries.

CONCLUSION

The first year of incidence validated at the "Registre général des cancers de Lille et de sa région" shows a completeness of records with regards to studied criteria. The comparison with national data shows an overincidence of cancers related to tobacco and alcohol consumption in the geographical area covered by the registry. The incidence of lip-mouth-pharynx cancer in men is the highest of all French registries.

[Renal cell carcinoma of patients younger than 40 years old]

CONTEXT

Clinical and pathological characteristics of renal cell carcinoma (RCC) of patients younger than 40 years old are not well known. The objective of this study was to analyze these characteristics by comparison to a group of patients aged 58 to 62.

METHODS

Retrospective study of a group of patients aged less than 40 years old (group 1, n=44) and a group of patients aged 58 to 62 years old (group 2; n=106) treated surgically for a renal mass from January 2000 to July 2009. A comparative analysis of clinical, pathological characteristics and of cancer-specific survival was performed. Specific survival was calculated with the Kaplan-Meier method and compared with the Log-Rank test. Univariate and multivariable analysis were performed to assess and quantify the effect of age on cancer-specific survival. Covariates were gender, age group, tumor size, pT stage, histological sub-type and Fuhrman grade.

RESULTS

Clinical and pathological characteristics were similar in both groups (P>0.05) except for histological sub-type (56% of clear cell RCC for group 1 versus 82% for group 2). In the group of patients younger than 40 years, translocation RCC represented 23% of all RCCs. Cancer-specific survival at five years was similar in both groups (80% and 76% for group 1 and 2 respectively, P>0.58). Fuhrman grade was the only independent prognostic factor of cancer-specific survival (P=0.001).

CONCLUSION

Patients younger than 40 years were more likely to have a translocation RCC than their older counterparts for who clear cell RCC represented the main histological sub-type. Cancer-specific survival was similar between both groups. Only a systematic specific immunostaining for TFE3 or TFEB will allow to assess the exact incidence and prognosis of this entity.

[Photodynamic therapy and prostate cancer]

PURPOSE

Photodynamic therapy (PDT) is an innovative therapeutic modality in urologic oncology.

MATERIAL AND METHODS

We reviewed the current literature on principles and modalities of PDT in prostatic oncology.

RESULTS

Focal therapy of prostate cancer is an application field of PDT. Clinical phase II studies are ongoing to determine PDT efficacy and safety in this indication. PDT as salvage treatment after prostatic radiotherapy has been tested. Carcinologic results were promising but important side effects were reported. Individual dosimetric planification is necessary to avoid this toxicity.

CONCLUSION

PDT first clinical experience for prostate cancer has showed its technical feasibility. Several research ways are currently in study to improve carcinologic efficacy and to limit potential side effects.

Ectopic hyperprolactinaemia in a woman with a mesocolic perivascular epithelioid cell tumor ("PEComa")

Ectopic prolactin secretion remains exceptional and originates mainly from malignant tumors. We report the case of a 47-year-old woman who presented amenorrhea leading to unravel important hyperprolactinaemia (269 ng/mL) with no hypothalamo-pituitary mass on magnetic resonance imaging (MRI). Pelvic imaging revealed the presence of a large pelvic mass that originated from the mesocolon. After complete surgical extraction, histological examination was in favour of a "perivascular epithelioid cell tumor" (PEComa). Prolactin levels normalized after surgical extraction and remained normal after a 3-year follow-up, totally free of tumour recurrence and/or metastasis. This suggests that hyperprolactinaemia was most likely related to the PEComa, despite negative reactions with antiprolactin antibodies at immunohistochemistry. Alternatively to a direct prolactin secretion by the tumor, one could hypothesize that the tumour secreted a prolactin stimulating factor or a dopamine antagonist that could not be identified. In conclusion, in face of an important hyperprolactinaemia without any hypothalamic-pituitary mass, it remains important to search for an ectopic prolactin production, such as a PEComa.

Respiratory epithelial adenomatoid hamartomas of the sinonasal tract

We report the clinicopathologic features of two cases of respiratory epithelial adenomatoid harmartoma (REAH) of the sinonasal tract. Hamartomas are rare in the nasal cavity. Histologically, these lesions were characterized by a glandular proliferation lined by ciliated respiratory epithelium originated from the surface epithelium. The two patients were evaluated by a gastroenterologist to assess intestine colocalization. The treatment was a complete surgical resection through limited approach. We should be aware of this entity as a differential diagnosis for inverted papilloma and well-differenciated adenocarcinoma. Fine histopathological analysis is necessary to avoid aggressive surgery for this benign lesion.

Post-traumatic fibro-osseous lesion of the ribs: a relatively under-recognised entity

AIM

To report the description of a rare benign osseous lesion affecting the ribs entitled post-traumatic fibro-osseous lesion (PTFOL).

METHODS

Seven cases of PTFOLs were retrieved from the archives of the University Hospital of Lille. Histological slides were reviewed and lesions were classified according to the histological patterns described by McDermott et al. Clinical and follow-up data were obtained from the patients' charts.

RESULTS

PTFOLs occurred principally in men (mean age 31.8 years) with a known or suspected previous chest injury for four of them. No previous cancer was noted. Radiologically, PTFOLs readily presented as an isolated expansive lucency with a sclerotic rim located on the last five ribs. A constant increased uptake of radionucleotide was noted on bone scan. Microscopically, two fibro-osseous, four xanthomatous and one mixed pattern were individualised. Lesions were characterised by a network of anastomosing bone trabeculae without osteoblast lining within a fibrous stroma. A zonal maturation from woven to peripheral lamellar bone was characterised. Central sheets of lipid-laden histiocytes were conspicuous in the xanthomatous type. For each patient, clinical follow-up was excellent, without any recurrence.

CONCLUSIONS

This is the second largest series of PTFOLs, which is considered to be a dysplastic healing process after trauma. It may be symptomatic or shown by imaging studies realised for unrelated reason. PTFOL is regularly misdiagnosed with other more common lesions of the ribs, such as fibro-osseous dysplasia, osteoma osteoid and benign fibrous histiocytoma. Its recognition is of importance because no follow-up is needed after resection.