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O Cussenot

Publications and source records attributed to O Cussenot.

At least 55 records · Page 3Linked to original sources
PubMed1999

FGF7/KGF triggers cell transformation and invasion on immortalised human prostatic epithelial PNT1A cells.

Fibroblast growth factor 7 (FGF7/KGF) is synthesized exclusively by fibroblasts in normal tissues; it acts as a potent mitogen on epithelial cells, through interaction with the FGF7-specific receptor FGFR2/IIIb. To examine the importance of this growth factor both to prostate physiology and to prostate-cancer progression, we have tested the exogenous effect of FGF7. Thus, by mimicking the paracrine pathway (on proliferation, growth in soft agar and invasion) on the human prostatic epithelial cell line PNT1A positively checked for FGFR2/IIIb expression, FGF7 significantly enhanced cell proliferation at an optimal concentration of 7.5 x 10(-11) M, but no significant invasion or growth in soft agar were observed. To confirm FGF7 properties on human prostatic epithelial cells, we constitutively expressed FGF7 by transfecting PNT1A cells with FGF7-cDNA. The FGF7-transfected clones, PNT1A/ FGF7-T5 and PNT1A/FGF7-T6, were stable and expressed FGF7. Analysis of the FGF7-autocrine loop on the non-tumorigenic epithelial cells PNT1A showed acquired invasive potential in in vitro extracellular-matrix migration assays, specifically inhibited by an FGF7-neutralizing antibody, and over-expressed factors implicated in the migration process: the metalloproteinase MMP-1 and the plasminogen activator uPA. Taken together, these results demonstrate a role for FGF7 in triggering invasion of human prostatic epithelial cells. Furthermore, these FGF7-transfected clones exhibited functional and physiological differences from the original PNT1A cell line: anchorage-independent growth, growth in serum-free media and increased proliferation. These data confirm the oncogenic function of FGF7 in prostate progression potentially acting through paracrine and/or autocrine regulatory pathways.

Cell Division↗
PubMed1999

Upregulation of endothelin 1 and its precursor by IL-1beta, TNF-alpha, and TGF-beta in the PC3 human prostate cancer cell line.

Increasing evidence indicates that endothelin 1 (ET-1) is implicated in prostate tumour progression. However, data on ET-1 regulation in human prostate and prostate cancer cell lines are lacking. In this study, regulation of ET-1 and its precursor big ET-1, using PC3 cells, a human bone metastatic prostatic carcinoma cell line, was addressed. ET-1 and big ET-1 assays demonstrated greater secretion of both peptides in the presence of 10% fetal calf serum (FCS) as compared with 0.5% FCS. Incubation of PC3 cells in the absence and presence of various cytokines and growth factors known to be implicated in prostate stroma-epithelium interactions, revealed that IL-6, FGF7/KGF and FGF2/bFGF had no effect on ET-1 and big ET-1 secretion, whereas interleukin 1beta (IL-1beta), tumour necrosis factor alpha (TNF-alpha) and transforming growth factor beta (TGF-beta) stimulated their secretion in a concentration-dependent manner. Binding experiments indicated the presence of specific ET-1 receptors in PC3 cells: Kdapp = 1.1 x 0.2 x 10(-10)M, Bmax = 2660 +/- 390 sites/cell. Data analysis demonstrated the presence of only the ETA receptor subtype in PC3 cells. In conclusion, our results indicate that the implication of ET-1 in prostate cancer is likely to be mediated via paracrine/autocrine control of cell factors.

Cytokines↗
PubMed1999

Vitamin D receptor polymorphisms as markers in prostate cancer.

Polymorphisms in the vitamin D receptor (VDR) gene have been analyzed in several studies for an association with prostate cancer (PCA) and odds ratios (OR) > or = 3 have been observed in study populations from North America. We studied three polymorphisms in the VDR gene (poly-A microsatellite, TaqI and FokI RFLPs) in 105 controls and 132 sporadic PCA cases from France and in a collection of families from Germany and France. The polymorphisms near the 3' end of the gene were in linkage disequilibrium with an almost complete coincidence of the short poly-A alleles and t (presence of the restriction site) of the TaqI polymorphism, (contingency tables, P<0.0001). An association was found by logistic regression for the poly-A between PCA and the heterozygous genotype (S/L; S < 17, L > or = 17, OR=0.44, 95% confidence interval, CI=0.198-0.966, P=0.041). OR was lower in patients < or = 70 years old and patients with a Gleason score > or = 6. The Tt genotype of the TaqI RFLP also showed an association with PCA (OR=0.5, CI=0.27-0.92, P=0.026). This association was also stronger for patients < or = 70 years old (OR=0.31, CI=0.15-0.63, P=0.001). The risk alleles were S and t alleles as indicated by the OR of the homozygotes, although these were not significant. The FokI RFLP at the 5' end of the gene did not reveal any association (P>0.7). While some association studies differ between Europe and North America, our present findings with the VDR gene agree with those from North America, indicating a weak but general role of the VDR in PCA susceptibility.

Aged↗
PubMed1999

Loss of heterozygosity at chromosome arm 13q and RB1 status in human prostate cancer.

Aberrations of the long arm of chromosome 13 are common in prostate cancer and were initially attributed to alterations of the RB1 gene in band q14 of the chromosome. However, prostate tumors generally yield normal p110RB1 nuclear staining despite loss of heterozygosity (LOH) at the RB1 locus. Our previous analysis of chromosome arm 13q showed allelic loss in 41% of primary prostate tumors. To refine our knowledge of 13q, we extended our previous LOH study by using more polymorphic markers to analyze more prostate tumors. Sixty human prostate carcinomas were screened for allelic loss on 13q by using 13 13q-specific markers. LOH on the long arm of chromosome 13 was found in 39 (65%) of the 60 tumors. Furthermore, 33 of these 39 tumors had evidence of allelic loss involving a region of 13q14 containing RB1. Because immunohistochemical assessment of pRb expression is controversial in prostate tumors, we used a quantitative reverse transcription polymerase chain reaction (RT-PCR) method to determine whether RB1 is the target tumor suppressor gene in this region. RB1 mRNA steady-state levels were determined in 12 prostate tumors preselected on the basis of presumed deletion at the RB1 locus and four prostate tumors without LOH at the RB1 locus; five normal prostate specimens were used as controls. One of the 12 assessable prostate tumors with presumed LOH at RB1 showed a corresponding decreased in RB1 mRNA expression, whereas none of the four tumors without LOH at RB1 locus showed such a decrease. This study, based on another technical approach, confirms that RB1 is not the main target of the observed LOH at 13q14.3, and raises the possibility that another tumor suppressor gene in this region plays a key role in prostate cancer.

Chromosomes, Human, Pair 13↗
PubMed1999

An experimental model of bulbar urethral stricture in rabbits using endoscopic radiofrequency coagulation.

OBJECTIVES: To develop an experimental model of endoscopic urethral stricture mimicking the human clinical situation. METHODS: Twenty-four New Zealand male rabbits were included. Eighteen animals (study group) underwent videourethroscopy with a pediatric resectoscope, and a 3 to 5-mm-long circumferential electrocoagulation of the bulbar urethra was performed, without postoperative urinary diversion. Six animals underwent the same procedure without application of electrocautery (control group). Each animal was assessed for urethral stricture on day 15 and day 30 by videourethroscopy and voiding cystogram. Among the study group, 8 animals were killed on day 15 and 10 on day 30 for histologic evaluation. All the control animals were killed on day 30 for histologic examination. RESULTS: Nine animals (50%) in the study group developed a significant bulbar stricture (reducing the lumen by more than 50%) at day 15. Histologic examination confirmed the presence of hyalin fibrosis mutilating the urethral wall. No spontaneous improvement of the stricture was observed on day 30. None of the controls developed urethral stricture, and histologic examination showed a normal urethra in each case. CONCLUSIONS: Endoscopic electrocoagulation of the urethral wall provides a reproducible model of stricture in the rabbit.

Animals↗
PubMed1999

(CAG)nCAA and GGN repeats in the human androgen receptor gene are not associated with prostate cancer in a French-German population.

Alleles of the CAG and the GGC repeat in the first exon of the human androgen receptor (AR) gene have been shown to be associated with the risk of (advanced) prostate cancer. These studies had been carried out in the United States. We have analysed these polymorphisms in a French-German collection of 105 controls, 132 sporadic cases, and a sample of prostate cancer families comprising 85 affected and 46 not affected family members. The allele distributions were very similar in all four groups and chi square statistics on contingency tables did not detect any significant differences. The relative risk (odds ratio, OR) were calculated using logistic regression and did not reach significance despite sufficient numbers of patients and controls. Typical results were OR = 1.007; 95% Confidence Interval (CI) 0.97-1.1, P = 0.87 for CAG as continuous variable and OR = 1.2 (95% CI 0.7-2.0), P = 0.47 for CAG classes < 22 and > = 22 repeats. Similar results were obtained for subgroups defined by age or Gleason score. We conclude that these polymorphisms can not be used as predictive parameters for prostate cancer in the French or German population.

Aged↗
PubMed1999

Adenovirus-mediated gene transfer in dog prostate: a preclinical study of a relevant model system for gene therapy of human prostatic cancer.

This present study evaluates the potential of adenovirus-mediated gene transfer (AMGT) to the prostate of normal laboratory beagles. Many morphological and histological similarities can be noted between dog and human prostate. Moreover, dogs can spontaneously develop prostate cancer with a clinical and biological outcome identical to that in man. Firstly we showed the capacity of human adenovirus to infect canine prostatic cells in vitro. Secondly, we injected transrectally in the dogs' prostates 2x10(9) plaque forming units of a first generation recombinant adenovirus vector harboring the reporter gene beta-galactosidase (AdRSVbetagal). Seven days after the adenoviral delivery, we observed expression of the transgene in both prostates, and exclusively in epithelial cells. Despite a cellular and a humoral immune response, the infusion appeared safe, since the dogs had no fever and presented no urinary symptoms. This study constitutes the first evaluation of AMGT in dog prostate and provides a basis for gene therapy treatment of prostate carcinoma-bearing patients.

Journal Article↗
PubMed1999

Thermal radiofrequency induced porcine ureteral stricture: a convenient endourologic model.

PURPOSE: To establish a reliable model of iatrogenic ureteral stricture mimicking the human clinical situation in order to experiment with new site-specific endourologic treatment concepts. MATERIALS AND METHODS: After cystoscopic insertion of a 7F right ureteral catheter, we induced external thermal radiofrequency injury to the right upper third ureter at low power setting (10 W) using an open surgical approach in 13 pigs. Three pigs considered as controls underwent the same procedure without application of electrocautery. All 16 animals were initially assessed at 8 days; 3 study animals and the 3 controls were followed for 6 weeks. RESULTS: No control animals had strictures. Significant upper third ureteral strictures with marked hydronephrosis where achieved in all study animals after a mean interval of 9 days, as evidenced by ultrasound examination and retrograde ureteropyelography. Endoscopic retrograde access to these strictures was always possible (mean length 1.4 cm.). Histologic examination displayed severe disorganization of the muscular layer by dense fibrosis composed of collagen bundles with few scattered fibroblasts. No spontaneous improvement of the stricture was observed in the 3 animals reassessed at 6 weeks. CONCLUSIONS: Externally applied radiofrequency energy to porcine ureter provides a reproducible model of fibrous stricture resembling its clinical counterparts.

Animals↗
PubMed1999

Ureteral gene transfer to porcine induced strictures using endourologic delivery of an adenoviral vector.

PURPOSE: Direct gene transfer to the ureter is an attractive approach to prevent restenosis after endourologic management of ureteral strictures. We therefore assessed the rationale for adenovirus-mediated gene transfer in the ureter in vitro and in vivo using a porcine model. MATERIALS AND METHODS: Primary cultures of porcine ureteral epithelial and stromal cells were infected with an adenoviral solution carrying a nucleus-targeted beta-Galactosidase (beta-Gal) reporter gene (6.5 10(8) pfu/ml.). In addition, in order to mimic the human clinical situation, we have devised a model of thermally-induced stricture in porcine ureter which produced tight fibrotic stenosis within 8 days. Using a purposely designed channelled balloon catheter prototype, these strictures were endoscopically dilated and then instilled with the same beta-Gal adenoviral construction. RESULTS: Application of recombinant adenovirus harboring a nucleus-targeted beta-Gal reporter gene to cultured porcine urothelial and stromal cells resulted in high transduction efficiency of up to 99% and 84% respectively. Seven days after infection, X-Gal staining of the strictured ureters demonstrated transfection up to 2 mm. depth within the fibrosis, confirmed by polymerase chain reaction (PCR) analysis. Adjacent and distal spread of the virus was excluded by histochemistry (X-Gal staining) and PCR. CONCLUSION: This data represents the first report of adenovirus-mediated gene transfer to the ureter. It remained site specific by endourologic retrograde clinically applicable techniques.

Adenoviridae↗
PubMed1999

[Epidemiology of familial prostatic cancer: 4-year assessment of French studies].

OBJECTIVES: (1) To determine the frequency of familial (at least 2 cases) and hereditary forms of prostate cancer (CaP), (2) to define the results according to the patient's age at diagnosis, as various epidemiological studies have demonstrated a possible familial aggregation of CaP in about 15 to 25% of cases. Carter's familial segregation study (P.N.A.S. 1992, 89, 3367-71) showed that a genetic predisposition, with autosomal dominant transmission, could be responsible for 9% of all cases of prostate cancer. MATERIAL AND METHODS: We conducted a systematic genealogy study of patients suffering from newly diagnosed CaP or followed for known CaP in 3 French urological centres, by means of questionnaires completed by the patients. Subsequently, a national collection of families with at least 2 cases of CaP identified families with hereditary forms of CaP. Hereditary cases were considered to be those presenting at least: one CaP in three 1st degree relatives, or 3 cases over 3 generations in the same branch of the family (paternal or maternal), or finally 2 early cases before the age of 55 years. Statistical analysis used the univariate logistic regression test between family status and the medical centre or the patient's age at diagnosis. RESULTS: From July 1994 onwards, we included 801 patients (all stages combined) in the systematic study and 110 patients (13.7%) were excluded (refusal to participate, advanced age). For 691 of the families studied (Brest: 225, Nancy: 249, Paris St Louis: 217), we observed 32 (14.2%), 29 (11.6%), 37 (17.1%) of familial forms (mean: 14.2%) and 11 (4.9%), 6 (2.4%), 8 (3.7%) of hereditary forms (mean: 3.6%), respectively (no significant differences between centres). Analysis of the results according to age at diagnosis of CaP also showed a higher incidence of familial (significant difference) and hereditary forms (limit of significance) for CaP occurring at a younger age (before 65 years). The national collection collected a total of 624 familial forms of CaP, including 236 (37.8%) cases of hereditary forms; 115 families were informative for the genetic linkage study. CONCLUSION: These results confirm the data of earlier studies, revealing about 15 to 25% of familial forms of CaP and 5 to 10% of hereditary forms. Similarly, the systematic study confirmed the earlier onset of CaP in patients with a genetic predisposition. These data therefore encourage systematic questioning of patients for a family history of CaP in order to propose targeted screening of high-risk subjects in the families concerned and to intensify identification of hereditary forms in order to investigate the genes involved.

Aged↗
PubMed1999

[Genetic analysis of familial prostatic cancer: localization of a gene predisposing to prostatic cancer (PCaP) on chromosome 1q 42.2-43].

OBJECTIVES: To conduct genetic linkage analysis in order to localize predisposition genes for hereditary prostate cancer (CaP), as various epidemiological studies have demonstrated a family aggregation in 15 to 25% of cases, and the development of hereditary forms in 5 to 10% of cases of CaP. MATERIAL AND METHODS: A genetic study on 47 French and German families included 122 patients and 72 subjects considered to be healthy after PSA assay. This study was conducted by linkage analysis of 364 microsatellite markers distributed throughout the genome (on average every 10 cM). RESULTS: Parametric and nonparametric linkage analysis identified a locus on chromosome 1q 42.2-43, which could be with a gene predisposing to CaP (called PCaP). The primary site was confirmed by several markers, using 3 different genetic models. The maximum LOD score (probability of linkage between the locus and the disease) on two-point analysis was 2.7 for the D1S2785 marker. Parametric and nonparametric multipoint analysis provided an HLOD score and an NPL score of 2.2 and 3.1, respectively (with P = 0.001). Heterogeneity analysis with calculations of LOD scores by multipoint analysis estimated that up to 50% of hereditary CaPs were related to this locus, with a heterogeneity probability of 157/1. Analysis of a subgroup of 9/47 families characterized by early onset CaP (before the age of 60 years) confirmed the very high probability of localization of a predisposition gene at locus 1q42.2-43 for these families (multipoint LOD score and NPL score of 3.31 and 3.32, respectively; with P = 0.001). CONCLUSION: The identification of predisposition genes will eventually allow identification within certain families of those subjects who have inherited the genetic abnormality and who therefore present a high risk of CaP. It will then be possible to perform targeted screening of CaP in order to diagnose CaP as early as possible.

Adult↗
PubMed1999

[Comparison of biomechanical properties of the vaginal fixation in bladder neck suspensions according to the Burch technique and a percutaneous technique].

UNLABELLED: Bladder neck suspension or colpo-suspension can be performed via retropubic or percutaneous transvaginal approaches. A higher success rate is observed for retropubic procedures. One of the hypotheses proposed, but not yet verified, is that the retropubic approach allows better quality vaginal fixation than the percutaneous approach. OBJECTIVE: The objective of this study was to compare the biomechanical properties of vaginal fixation according to the Burch procedure and according to a percutaneous technique (Vesica; Boston Scientific). MATERIAL AND METHODS: We performed bladder neck suspension according to the Burch technique (2 points) on the left and according to the Vesica percutaneous technique on the right, on 6 fresh cadavers (mean age 8-5 years), using the same suture material. Vaginal fixations were subsequently excised. The depth of penetration into the vagina was measured and a computerized traction test (Lloyd Instruments, France) was performed on these fixations. The maximum force of traction before rupture was measured. RESULTS: No significant difference was demonstrated for any of the measurements. CONCLUSION: Vaginal fixation of bladder neck suspension performed according to the Burch technique or via a percutaneous technique (Vesica) present equivalent biomechanical properties.

Aged↗
PubMed1998

Assessment of microsatellite instability in urine in the detection of transitional-cell carcinoma of the bladder.

Loss of heterozygosity (LOH) and alterations in microsatellite DNA markers have been reported in bladder-cancer tumors. We have studied, in a blinded fashion, using PCR-based microsatellite analysis, genetic alterations of cells exfoliated in urine of 59 Caucasian patients and control patients; 31 with initially confirmed bladder transitional-cell carcinoma (TCC), 17 with signs and symptoms suggestive of bladder cancer, 6 control patients who underwent renal transplantation, and 5 control patients with urolithiasis. Microsatellite analysis of cells exfoliated in the urine allowed the diagnosis of 83% (10/12) of patients with bladder TCC recurrence confirmed by cystoscopy, while 100% of patients followed up for transitional-cell carcinoma of the bladder for up to 12 months without evidence of tumor recurrence upon routine cystoscopy showed no microsatellite alterations. None of the patients without neoplasia (negative controls) had any microsatellite alterations, whereas all patients who underwent renal transplantation had additional new alleles corresponding to contamination with donor's renal and urothelial cells (positive controls). No control patients had any evidence of transitional-cell carcinoma by cystoscopy. Our results provide objective evidence that non-invasive molecular detection of bladder TCC by microsatellite analysis is reproducible with a sensitivity of 83% and a specificity of 100% in Caucasian patients. This non-invasive procedure represents a potential clinical tool for the detection and the screening of bladder TCC.

Adult↗
PubMed1998

PTEN/MMAC1/TEP1 involvement in primary prostate cancers.

The PTEN/MMAC1/TEP1 gene, located at 10q23.3, is a tumor suppressor gene responsible for the familial cancer syndromes Cowden disease and Bannayan-Zonana syndrome, and is commonly somatically mutated in several types of cancers. Mutations of the PTEN gene have been found in prostate cancer cell lines and LOH at 10q22-24 in prostate tumors have also been described with a high frequency. To determine the role of this gene in prostate tumorigenesis, we therefore analysed 22 primary tumors for loss of heterozygosity (LOH) within the 10q22-23 region such that tumors hemizygous at those loci may be examined for somatic PTEN mutations. Losses of heterozygosity of at least one locus was found in 12 (55%) of the 22 tumors DNAs. Among these, six tumors exhibited allele loss in the interval between D10S1765 and D10S541 wherein lies the PTEN gene. We searched the entire coding region of PTEN for somatic mutations in these six tumors. One somatic mutation (17%), a 1 bp deletion, was detected in exon 7 of the gene, in one tumor, indicating that somatic mutations of the PTEN gene may occur in primary prostate tumors.

Chromosomes, Human, Pair 10↗
PubMed1998

Molecular analysis of the FHIT gene in human prostate cancer.

A variety of studies suggest that the FHIT gene, which encompasses the fragile site at 3p14.2, is a candidate tumor suppressor gene in several forms of human cancer. To determine whether the FHIT gene is altered in prostate carcinomas, we examined 15 prostate tumors, four normal prostate tissue specimens and RNA from a pool of 62 normal human prostate tissues (Clontech) for the integrity of FHIT transcripts, using a robust single-stage PCR and a nested PCR method. In each case a major FHIT-specific full-length product was observed. Additional aberrantly sized products, which were more numerous in the nested PCR strategy, were present at a far lower level than the full-length transcripts in 14 of 15 tumors, three of four normal human prostate tissues and in the pooled normal prostate RNA. Sequence analysis revealed that these aberrant products corresponded to alternatively spliced FHIT transcripts, which were neither more numerous nor more prominent in the tumors than in the normal prostate specimens. Deletion at the FHIT locus was also evaluated by using three intragenic polymorphic markers (D13S1481, D3S1300, and D3S1234). Allelic loss was observed in two tumors, but these genomic alterations did not correspond to the aberrant FHIT transcripts. DNA analysis, furthermore, suggested that the tumor heterogeneity was not a likely explanation for presence of normal and alternatively spliced FHIT transcripts in the prostate tumors. In conclusion, we detected neither frequent loss of heterozygosity nor tumor specific transcripts of the FHIT gene in human prostate cancer.

Acid Anhydride Hydrolases↗
PubMed1998

The role of laser-induced autofluorescence spectroscopy in bladder tumor detection. Dependence on the excitation wavelength.

We assessed the ability of laser-induced autofluorescence spectroscopy to distinguish neoplastic urothelial bladder lesions from normal or nonspecific inflammatory mucosa. Three different pulsed laser excitation wavelengths were used successively: 308 nm (xenium chloride excimer laser), 337 nm (nitrogen laser) and 480 nm (coumarin dye laser). The excitation light was delivered by a specially devised multifiber catheter connected to a 1-mm core diameter silica monofiber introduced through the working channel of a standard cystoscope with saline irrigation. The captured fluorescence light was focused onto an optical multichannel analyzer detection system. Performance of this device was evaluated in 25 patients after obtaining consent and immediately before transurethral resection of a bladder tumor. Spectroscopic results were compared with histological findings. At 337- and 480-nm excitation wavelengths, the overall fluorescence intensity of bladder tumors was clearly decreased compared to normal urothelial mucosa regardless of tumor stage and grade. At the 308-nm excitation wavelength, the shape of the tumor spectra, including carcinoma in situ, was markedly different from that of normal or nonspecific inflammatory mucosa. No absolute intensity determinations were required in this situation, since a definite diagnosis could be established based on the fluorescence intensity ratio at 360 and 440 nm. This spectroscopic study could be particularly useful in designing a simplified autofluorescence imaging device for detection of occult urothelial neoplasms.

Aged↗
PubMed1998

Urethral graciloplasty for treatment of female intrinsic sphincter deficiency: rationale for the transvaginal approach: an anatomical study.

PURPOSE: To compare the retropubic and transvaginal approaches in terms of the length of gracilis muscle available for female urethral graciloplasty. MATERIALS AND METHODS: Two groups of female cadavers were submitted to bilateral gracilis muscle dissection, followed by urethral graciloplasty using either the standard retropubic approach or the transvaginal approach. The two groups were studied in terms of various muscle characteristics, in particular the length of muscle that could effectively be wrapped around the bladder neck. RESULTS: Because muscle transfer to the perineum was more direct, the transvaginal approach provided a greater functional length of gracilis for effective periurethral wrapping than the retropubic approach (mean: 8.4 cm. versus 5.2 cm., p = 0.0022). CONCLUSION: The transvaginal approach allows a more "proximal" graciloplasty and should therefore be evaluated clinically to provide circumferential bladder neck support without tension.

Aged↗