Bladder stretch alters urinary heparin-binding epidermal growth factor and antiproliferative factor in patients with interstitial cystitis

PURPOSE: The etiology of interstitial cystitis is unknown. Urine from patients with interstitial cystitis has been shown to inhibit urothelial proliferation through a putative antiproliferative factor and to contain decreased levels of heparin-binding epidermal growth factor-like growth factor (HB-EGF) compared to controls. Stretch of detrusor smooth muscle cells is known to stimulate HB-EGF production. Because bladder hydrodistention sometimes alleviates the symptoms of interstitial cystitis, we determined whether the stretch stimulus of hydrodistention alters antiproliferative factor activity and/or HB-EGF in interstitial cystitis urine specimens. MATERIALS AND METHODS: Urine was collected immediately before, and 2 to 4 hours and 2 weeks after hydrodistention from 15 patients with symptoms and cystoscopic findings compatible with interstitial cystitis and 13 controls. Hydrodistention was performed with the subject under general or regional anesthesia and bladders were distended to 80 cm. water 3 times. Urinary HB-EGF was measured by enzyme-linked immunosorbent assay and urinary antiproliferative factor activity was determined by measuring 3H-thymidine uptake by normal human bladder urothelial cells. RESULTS: Hydrodistention significantly increased urinary HB-EGF in patients with interstitial cystitis toward normal control values (before distention p = 0.003, 2 weeks after distention p = 0.67). Urine antiproliferative factor activity decreased significantly after hydrodistention in patients with interstitial cystitis. However, antiproliferative factor activity in interstitial cystitis and control specimens was still statistically different 2 weeks after distention (before distention p = 0.0000004, 2 weeks after distention p = 0.04). CONCLUSIONS: Bladder stretch increased HB-EGF and conversely reduced antiproliferative factor activity in urine from patients with interstitial cystitis but not controls up to 2 weeks after distention. These results provide additional evidence for the possible role of antiproliferative factor and decreased HB-EGF in the pathophysiology of interstitial cystitis. To our knowledge this is also the first human study to show that in vivo bladder stretch can alter urinary factors that regulate cell growth.     

A diagnostic in vitro urine assay for interstitial cystitis

Objectives. A low molecular weight urine factor that inhibits the proliferation of normal bladder epithelial cells in vitro was previously shown to be present significantly more often in the urine of patients with interstitial cystitis (IC) than in the urine of asymptomatic age-, race-, and sex-matched control subjects. We sought to determine the specificity of this finding for IC by determining whether the urine of patients with other urogenital inflammatory disorders also contains a factor that inhibits bladder epithelial cell proliferation.Methods. Urine was collected from women with IC, acute bacterial cystitis, or vulvovaginitis, as well as from asymptomatic control women. The proliferation of primary normal adult bladder epithelial cells was determined by measuring ³H-thymidine incorporation in vitro.Results. Osmolality- and pH-corrected urine specimens from 50 (86%) of 58 women with IC significantly inhibited human bladder epithelial cell proliferation compared with 3 (8%) of 36 asymptomatic control women, 7 (12%) of 58 women with bacterial cystitis, and 0 (0%) of 12 women with vulvovaginitis (P < 0.001 for the comparison of mean percent change in ³H-thymidine incorporation with IC urine versus urine from each of the control groups). Optimal sensitivity and specificity values of 91.4% and 90.6%, respectively, were achievable at a cutoff of 25% inhibition of ³H-thymidine incorporation, using all three control groups.Conclusions. The measurement of urine antiproliferative activity may be a useful noninvasive means for diagnosing IC in women.     

ANTIPROLIFERATIVE ACTIVITY IS PRESENT IN BLADDER BUT NOT RENAL PELVIC URINE FROM INTERSTITIAL CYSTITIS PATIENTS

PURPOSE: To determine whether an antiproliferative urine factor that we previously discovered to be specific for urine from interstitial cystitis (IC) patients originated in the lower urinary tract or a more proximal site. MATERIALS AND METHODS: Sequential catheterized urine specimens were collected under sterile conditions from the bladder and renal pelvis of 20 IC patients and one control patient (with stress incontinence). Antiproliferative activity was determined by 3H-thymidine incorporation of primary normal adult bladder epithelial cells cultured with pH- and osmolality-corrected bladder or ureteral urine specimens; significant inhibition was defined as a change in 3H-thymidine incorporation greater than 2 standard deviations from the mean of control cells. RESULTS: Bladder urine specimens from 19 of 20 IC patients significantly inhibited 3H-thymidine incorporation as compared to cell medium alone (mean change for bladder specimens = -68.7+/-7.5%), while a renal pelvic specimen from only 1 of 20 IC patients inhibited proliferation significantly (mean change for renal pelvic specimens = 3.2+/-3.4%) (p<.001 by Fisher's exact test). The one inhibitory IC renal pelvic specimen inhibited by 31% while a bladder specimen obtained during the same procedure inhibited by 94%. In comparison, neither bladder nor renal pelvic urine from the control patient had inhibitory activity. CONCLUSIONS: The antiproliferative factor previously found in the urine of IC patients appears to be made and/or activated in the distal ureter or urinary bladder.     

A comparison of multiple urine markers for interstitial cystitis

PURPOSE: We measured several urine markers in 24-hour specimens from patients with interstitial cystitis and healthy controls. For each marker we determined whether the urine level was significantly different in interstitial cystitis and control cases, and whether the marker level correlated with the symptom score. MATERIALS AND METHODS: Study participants included 36 female patients with interstitial cystitis and 36 age matched female volunteers. Multiple urine aliquots were obtained to measure the various markers. RESULTS: Certain markers were significantly increased in interstitial cystitis, including anti-proliferative factor, epidermal growth factor, insulin-like growth factor (IGF) binding protein-3 and interleukin (IL)-6. Markers significantly decreased in interstitial cystitis were heparin-binding epidermal growth factor-like growth factor, cyclic guanosine monophosphate and methylhistamine. Other markers were not significantly different in the interstitial cystitis and control groups, including total glycosaminoglycans, epitectin, hyaluronic acid, IL-8, IL-1 and nitrates plus nitrites. IGF-1 was undetectable in 24-hour urine samples but spot voided samples from the same interstitial cystitis population had IGF-1 levels similar to previously reported levels. The only significant association of marker with symptom score was a positive correlation of IL-6 with nocturia. For all markers the conclusions were the same whether the marker was normalized to creatinine or to 24 hours. CONCLUSIONS: This study confirmed several previously reported urine alterations in interstitial cystitis, including increased anti-proliferative factor, epidermal growth factor, IGF binding protein-3 and IL-6, and decreased heparin-binding epidermal growth factor-like growth factor and cyclic guanosine monophosphate. Of all markers studied anti-proliferative factor had the least overlap in the interstitial cystitis and control groups, and so it is the most likely candidate to become a diagnostic test.     

DO THE NATIONAL INSTITUTE OF DIABETES AND DIGESTIVE AND KIDNEY DISEASES CYSTOSCOPIC CRITERIA ASSOCIATE WITH OTHER CLINICAL AND OBJECTIVE FEATURES OF INTERSTITIAL CYSTITIS?

PURPOSE: We compared urine markers, bladder biopsy findings and clinical features of patients with symptoms of interstitial cystitis (IC) who did or did not meet the cystoscopic criteria defined by the National Institute of Diabetes and Digestive and Kidney Diseases. MATERIALS AND METHODS: Urine markers and symptom questionnaires were measured before and 1 month after bladder distention for IC. Bladder biopsies were taken at the time of distention. At distention patients were defined as meeting or not meeting the National Institute of Diabetes and Digestive and Kidney Diseases established cystoscopic criteria for IC. The 2 patient groups were compared. RESULTS: Urine marker levels were similar for the 2 groups, including antiproliferative factor, epidermal growth factor, heparin binding epidermal growth factor-like growth factor, cyclic guanosine monophosphate, interleukins 6 and 8, and methylhistamine. Bladder biopsy features were similar for the 2 groups. Bladder capacity with the patients under anesthesia was higher in those who did not meet the criteria (median 750 vs 1,000 ml, p = 0.005). Median age at symptom onset was 26 years in both groups. On the University of Wisconsin symptom scale patients who met the criteria had higher scores for daytime frequency (p = 0.002) and nocturia (p = 0.01). Symptom characteristics and symptom response after bladder distention were similar for the 2 groups. CONCLUSIONS: Patients who met the cystoscopic criteria had worse daytime frequency and nocturia, and lower bladder capacity under anesthesia. However, the 2 groups had similar urine markers and bladder biopsy findings. The cystoscopic criteria do not appear to identify a distinct pathophysiological subset of patients with IC symptoms.     

Chronic cystitis: Excretion of epidermal growth factor (EGF)/urogastrone (URO)

Summary To investigate the role of epidermal growth factor (EGF)/urogastrone (URO) in the cytoprotection of the urothelium in the urinary bladder we measured the concentration of EGF/URO by radioimmunoassay in urine from patients with chronic cystitis. The series comprised 12 patients with classical interstitial cystitis, 10 young females with recurrent bacterial cystitis and 12 children with recurrent cystitis together with sex- and age-matched controls. The results showed no variation in the substance concentration of EGF/URO in urine from cystitis patients and control groups. A negative correlation was found between 1) the urinary concentration of EGF/URO and increasing age, and 2) the excretion of EGF/URO per mol creatinine. The present study did not show a decreased output of EGF/URO in patients with chronic cystitis. Further studies are necessary in the evaluation of the physiological role of EGF/URO in the urinary tract.     

Heparin-binding epidermal growth factor-like growth factor functionally antagonizes interstitial cystitis antiproliferative factor via mitogen-activated protein kinase pathway activation

OBJECTIVE

To delineate the mechanism underlying the potential functional relationship between interstitial cystitis antiproliferative factor (APF) and heparin‐binding epidermal growth factor‐like growth factor (HB‐EGF), as APF has previously been shown to decrease the proliferation rate of normal bladder epithelial cells and the amount of HB‐EGF produced by these cells.

MATERIALS AND METHODS

APF‐responsive T24 transitional carcinoma bladder cells were treated with high‐pressure liquid chromatography‐purified native APF with or without HB‐EGF to determine the involvement of signalling pathways and proliferation by Western blot analysis, p38 mitogen‐activated protein kinase (MAPK) and extracellular signal‐regulated kinase (Erk)/MAPK assays, and 3‐(4,5‐dimethylthiazolyl‐2)‐2,5‐diphenyltetrazolium bromide (MTT) assay.

RESULTS

Cyclic stretch induced the secretion of HB‐EGF from T24 cells overexpressing the HB‐EGF precursor, resulting in enhanced proliferation. T24 cells treated with APF had increased p38MAPK activity and suppressed cell growth, events that were both reversed by treatment with a p38MAPK‐selective inhibitor. Activation of Erk/MAPK by HB‐EGF was inhibited by APF, and APF did not stimulate p38MAPK in the presence of soluble HB‐EGF or when cells overexpressed constitutively secreted HB‐EGF. Lastly, APF inhibitory effects on cell growth were attenuated by HB‐EGF.

CONCLUSIONS

These results indicate that HB‐EGF and APF are functionally antagonistic and signal through parallel MAPK signalling pathways in bladder cells.     

类肝素结合性表皮生长因子在人子宫内膜植入窗期的表达和意义

探讨类肝素结合性表皮生长因子 (HB-EGF)在人正常子宫内膜中的表达特点 ,评估其在子宫内膜的生长、分化及在植入窗期介导胚泡着床中的作用。采用免疫组织化学方法检测 5 6例正常子宫内膜 (1 6例增殖期 ,1 3例分泌早期 ,1 5例分泌晚期 ,1 2例植入窗期 )中 HB-EGF的表达及定位。结果 :HB-EGF在人各期子宫内膜均有表达 ,在植入窗期或分泌中期子宫内膜上皮细胞和间质细胞表达最强 ,并定位于腺上皮和腔上皮细胞表面 ,呈顶浆分泌状。结论 :HB-EGF存在于人各期子宫内膜 ,在植入窗期明显高表达可能参与介导胚泡着床 ,并与间质细胞的生长、分化有关 ,利于子宫内膜蜕膜化 ,为胚泡着床做准备。     

Effect of hyaluronic acid on urine nerve growth factor in cyclophosphamide‐induced cystitis

Objectives: To investigate how hyaluronic acid (HA) affects nerve growth factor (NGF) production and bladder overactivity in a cyclophosphamide (CYP)‐induced cystitis rat model. Methods: Female Sprague–Dawley rats received three intermittent intraperitoneal injections of CYP (75 mg/kg) or saline. Before or after CYP injection, HA was given intravesically and urine NGF was checked with creatinine correction. Bladder function was evaluated by cystometrograms under Zoletil anesthesia. Furthermore, the effect of HA was counteracted with hyaluronidase (HYAL). Bladder structural change was compared among groups with trichrome stain. Results: The intercontraction interval (ICI) significantly decreased in CYP‐injected rats in comparison to the saline‐injected controls. In the CYP‐injected groups, bladder HA instillation significantly increased the ICI, but did not change the maximum voiding pressure in comparison to the saline instillation. NGF production significantly increased in CYP‐injected rats, but decreased significantly with HA treatment. Treatment with HA had a more significant effect on urine NGF and the use of HYAL would eliminate this effect. Specific staining showed mucosa swelling after CYP treatment. Little HA coating on bladder mucosa could be found in HA‐treated rats. Conclusions: Present findings raise the possibility that HA could be an effective treatment for CYP‐related bladder overactivity through the involvement of NGF signaling.     

Changes in urine markers and symptoms after bladder distention for interstitial cystitis

PURPOSE: We evaluated changes in urine markers and symptom scores after bladder distention in patients with interstitial cystitis. MATERIALS AND METHODS: Study subjects were 33 new patients who had undergone no prior interstitial cystitis treatment. Urine specimens were taken before and 1 month after bladder distention. University of Wisconsin symptom scores were done the same day as the urine specimen collection. Urine marker levels and symptom scores before and after distention were compared. Changes in markers were tested for associations with changes in symptom scores and other markers. Markers and specific symptoms before distention were tested for their association with post-distention symptom improvement. RESULTS: After distention the median total University of Wisconsin score decreased significantly (28.5 before, 20 after, p <0.001). A total of 12 patients (36%) had at least 30% improvement in University of Wisconsin score, and 8 patients (24%) had at least 50% improvement. No pre-distention markers or symptoms predicted which patients would have a good response. There were 2 urine markers that improved significantly after distention: anti-proliferative factor activity (median -96% before, -17% after, p <0.001) and heparin-binding epidermal growth factor-like growth factor levels (median 0.34 ng/mg creatinine before, 4.1 after, p <0.001). None of the changes in urine markers associated with changes in symptom scores. CONCLUSIONS: The median symptom score for newly diagnosed patients with interstitial cystitis decreased after distention, but only a minority of patients had at least 30% symptom improvement. Bladder distention altered urine anti-proliferative factor activity and heparin-binding epidermal growth factor-like growth factor levels toward normal, but the mechanism of symptom relief after distention is still unknown.     

Prospective evaluation of candidate urine and cell markers in patients with interstitial cystitis enrolled in a randomized clinical trial of Bacillus Calmette Guerin (BCG)

We measured candidate urine biomarkers and bladder cell DNA cytometry in interstitial cystitis (IC) patients randomized to receive intravesical Bacillus Calmette Guerin (BCG) or placebo in a multicenter trial. Participants received 6 weekly instillations and were followed for 34 weeks. Urine was collected at baseline, prior to fourth treatment, and at study end. Antiproliferative factor (APF) activity was determined by 3H-thymidine incorporation assay; heparin-binding epidermal growth factor-like growth factor (HB-EGF) and epidermal growth factor-like growth factor (EGF) levels were determined by ELISA. Cellular DNA content was measured by image analysis to determine the mean hyperdiploid fraction (HDF) of the urine cell pellet. Associations between marker levels, and treatment or symptoms, were examined. Baseline APF positivity rate and mean levels of the other biomarkers were similar to previous smaller studies. During the week 34 follow-up, mean HDF decreased (P = 0.0003) and HB-EGF increased (P < 0.0001); both correlated weakly with decreased urgency. There was no difference in any biomarker between symptom responders and non-responders, but the percentage of responders was low and not significantly different for BCG versus placebo. APF positivity, decreased HB-EGF, increased EGF, and increased HDF were confirmed at baseline in IC patients. Changes in HDF and HB-EGF levels correlated weakly with changes in urgency, but the low BCG response rate prevented identification of additional associations between biomarker changes and treatment or symptoms.     

几丁聚糖促进兔膀胱黏膜上皮细胞生长的实验研究

目的 观察几丁聚糖对体外培养膀胱黏膜上皮细胞增殖的影响,并初步研究其机制,从而探讨其治疗间质性膀胱炎的可行性.方法 获取新西兰兔膀胱黏膜,Dispase酶消化法收集上皮细胞,分不同浓度(0.3、0.6、1.2、2.4、4.8 g/L)几丁聚糖实验组与对照组进行细胞原代培养.培养72h后,光镜下观察细胞生长增殖情况;N-乙酰氨基-β-D-氨基葡萄糖苷酶反应比色法测定几丁聚糖对膀胱上皮细胞增殖的影响;RT-PCR检测表皮生长因子受体(EGFR)mRNA的表达.结果与对照组相比,几丁聚糖在浓度＞0.3 g/L时能促进兔膀胱黏膜上皮细胞的增殖,促进作用在浓度为1.2g/L时最明显(P＜0.01),2.4、4.8 g/L时渐降低,但仍高于对照组(P＜0.01).兔膀胱黏膜上皮细胞中EGFR mRNA的表达亦与几丁聚糖浓度的浓度有关,浓度为1.2 g/L时EGFR mRNA的表达最明显(P＜0.01).结论 几丁聚糖体外可促进兔膀胱黏膜上皮细胞增殖,这种促细胞增殖作用可能与促进表皮生长因子与EGFR特异性结合而发挥其生理效应有关.     

Altered Expression of Bladder Mast Cell Growth Factor Receptor (c-kit) in Interstitial Cystitis

Objectives. To investigate the presence of mast cell growth factor receptors (c-kit) on bladder mast cells in interstitial cystitis (IC), a bladder condition occurring primarily in women. IC is characterized by pain, urgency, frequency, and mucosal microhemorrhages discernible with cystoscopy under general anesthesia. One of the prevailing theories to explain IC pathophysiology is the increased number of bladder mast cells, many of which are activated in at least a subgroup of IC patients. Stem cell factor (SCF), also known as c-kit ligand, is now recognized as the key molecule responsible for mast cell proliferation and is known to exert its action through specific surface receptors.Methods. Bladder specimens from patients with IC, identified by the criteria established by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), and control patients were obtained during diagnostic cystoscopy and were immediately fixed in 4% paraformaldehyde. They were then examined by immunohistochemistry for the unique proteolytic mast cell enzyme tryptase or the presence of c-kit, or both.Results. Bladders of IC patients contained a higher number of mast cells than control patients. However, mast cells in IC patients expressed fewer c-kit on their surface than those in control patients. These results could be explained if the c-kit were occupied by endogenous SCF or were downregulated, possibly by internalization after ligand-receptor interactions, making them inaccessible to immunocytochemical detection.Conclusions. Bladder mastocytosis and/or activation of mast cells, in at least a subpopulation of IC patients, may be explained by increased stimulation of mast cells by SCF. These results could be explained either by a mutation leading to constitutive activation of c-kit or overproduction of c-kit ligand leading to bladder mast cell proliferation in IC.     

Changes in epidermal growth factor receptor expression in human bladder cancer cell lines following interferon-alpha treatment

PURPOSE: We examined the regulation of epidermal growth factor (EGF) receptor (EGFR) expression in human bladder cancer cell lines by interferon-alpha (IFN-alpha), the ability of IFN-alpha to inhibit cell proliferation and the sensitivity of IFN-alpha pretreated cells to EGF. MATERIALS AND METHODS: Cell proliferation was determined using crystal violet colorimetric and clonogenic assays. EGFR expression was measured by flow cytometry using specific antibody or ligand binding approaches. RESULTS: After IFN-alpha (100 IU/ml) treatment cell surface EGFR expression was upregulated in 6 of 11 and down-regulated in 2 of 11 bladder cancer cell lines. The over expression of cell surface EGFR peaked within 48 to 96 hours and increased by 35% to 241% in individual cell lines. High level cell surface EGFR correlated with intracellular EGFR expression. Cell growth inhibition by IFN-alpha coexisted with EGFR over expression in the 6 lines. IFN-alpha treated cells remained sensitive to EGF treatment. CONCLUSIONS: IFN-alpha transiently up-regulates EGFR expression and inhibits in vitro growth in some human bladder cancer cells. IFN-alpha does not prevent EGFR from binding EGF or signal transduction via the EGF-EGFR pathway. This may have clinical implications for improving treatment based on EGFR targeting in select patients with bladder cancer.     

The role of bladder afferent pathways in bladder hyperactivity induced by the intravesical administration of nerve growth factor

PURPOSE: Interstitial cystitis, a chronic disease of the bladder, is characterized by urinary frequency, urgency and suprapubic pain. Nerve growth factor is a substance that may sensitize afferent nerves and induce bladder hyperactivity. It is often increased in the urine of patients with interstitial cystitis. We evaluated the role of Adelta and C fiber afferents in the type of bladder hyperactivity induced by the intravesical administration of nerve growth factor. MATERIALS AND METHODS: A total of 22 Wistar and 8 Sprague-Dawley adult female rats were anesthetized with 1.2 gm/kg urethane given subcutaneously. A transurethral catheter was inserted into the bladder. Some animals were pretreated with 125 mg/kg capsaicin injected subcutaneously 4 days before nerve growth factor administration. Cystometry was performed by slowly filling the bladder at a rate of 0.04 ml per minute for 15 minutes with a volume of up to 0.6 ml. Parameters measured included volume threshold and pressure threshold for inducing the micturition reflex, compliance, bladder contraction amplitude, number of contractions and the inter-contraction interval. Nerve growth factor (0.5 ml of 20 microg/ml in 10% dimethyl sulfoxide) or a vehicle solution (0.5 ml of 10% dimethyl sulfoxide) was infused into the bladder through a transurethral catheter and retained for 1 hour. RESULTS: In Wistar rats nerve growth factor increased the mean number of contractions by 111% versus controls (5.7 versus 2.7, p <0.05), and decreased the mean volume threshold by 41% (0.244 versus 0.412 ml, p <0.05). This effect of nerve growth factor was not detected in Sprague-Dawley rats. Capsaicin pretreatment increased the volume threshold by 59% but did not change nerve growth factor induced bladder hyperactivity. CONCLUSIONS: The intravesical application of nerve growth factor acutely induced bladder hyperactivity in Wistar but not in Sprague-Dawley rats. Because the C fiber afferent neurotoxin capsaicin did not change the effect of nerve growth factor, we believe that Adelta afferent neurons have a major role in nerve growth factor induced bladder hyperactivity.     

Percutaneous sacral third nerve root neurostimulation improves symptoms and normalizes urinary HB-EGF levels and antiproliferative activity in patients with interstitial cystitis

OBJECTIVES: A highly effective treatment for interstitial cystitis (IC) remains elusive. We determined whether sacral third nerve root (S3) percutaneous neurostimulation (PNS) might be effective in relieving symptoms of IC, as well as in normalizing urinary factors that are specifically altered in IC. METHODS: Six consecutive patients with symptoms and cystoscopic findings compatible with IC underwent 5 days of continuous S3 neurostimulation by way of leads placed percutaneously into the S3 foramen. Patients filled out voiding frequency diaries and pain and urgency questionnaires before PNS and at the end of PNS when the leads were removed. Urine specimens were collected at these two time points and measured for heparin-binding epidermal growth factor-like growth factor (HB-EGF) by enzyme-linked immunosorbent assay and for antiproliferative factor (APF) activity by (3)H-thymidine uptake by normal human bladder urothelial cells. RESULTS: S3 PNS significantly improved all measured parameters toward normal values. Voiding frequency decreased twofold from 23.1 +/- 4.6 to 10.6 +/- 4.0 voids daily during PNS (P = 0.0001). Pelvic pain on a scale of 1 to 10 decreased from 7.0 +/- 1.6 to 2.3 +/- 3.2 (P = 0.05). Urinary urgency on a scale of 1 to 10 decreased from 6.0 +/- 2.2 to 1.8 +/- 1.7 (P = 0. 02). Urinary HB-EGF concentration increased sevenfold from 1.5 +/- 2. 1 to 11.0 +/- 1.7 ng/mL (P <0.0001), and urinary APF activity decreased from -76.1% +/- 31% to -4.5% +/- 8.8% (P = 0.005). CONCLUSIONS: S3 PNS significantly decreased symptoms and normalized urinary HB-EGF and APF activity in patients with IC. These results suggest that permanent S3 PNS may be beneficial in treating IC.     

Over expression of platelet-derived endothelial cell growth factor/thymidine phosphorylase in patients with interstitial cystitis and bladder carcinoma.

PURPOSE: We examined whether the expression of angiogenic factors, such as platelet-derived endothelial cell growth factor/thymidine phosphorylase (PDEGF/TP) and transforming growth factor-beta, in bladder tissue correlates with the severity of symptoms, such as urinary urgency and bladder pain, in patients with bladder carcinoma and interstitial cystitis. MATERIALS AND METHODS: Bladder biopsy was performed in 32 patients with bladder carcinoma, including 19 with interstitial cystitis and 3 controls. Immunohistological staining for PDEGF/TP, transforming growth factor-beta and CD44 was performed in bladder specimens. PDEGF/TP in bladder tissues was also measured by enzyme-linked immunosorbent assay to examine the correlation of the expression of this factor with painful symptoms in patients with bladder carcinoma or interstitial cystitis. RESULTS: Immunohistochemical staining showed that PDEGF/TP stained in the submucosal layer beneath the basement membrane in bladder tissues of patients with interstitial cystitis and peritumoral areas of those with bladder carcinoma. In addition, PDEGF/TP, transforming growth factor-beta and CD44 stained in the same submucosal region and staining was observed at deeper submucosal levels in interstitial cystitis cases with severe rather than mild bladder pain. Quantitative analyses revealed that mean PDEGF/TP expression plus or minus standard deviation in tumor tissues of 10 patients with bladder carcinoma and pain was significantly higher than in tumor tissues of 22 with asymptomatic bladder carcinoma (129.3 +/- 70.7 versus 37.6 +/- 29.2 units per mg. protein). The mean expression of PDEGF/TP in peritumoral mucosa of patients with bladder carcinoma and pain was also significantly higher than in those with asymptomatic bladder carcinoma (75.5 +/- 42.1 versus 12.6 +/- 5.4 units per mg. protein). For interstitial cystitis mean expression in 6 patients with severe bladder pain was significantly higher than in 13 with moderate pain (79.2 +/- 59.2 versus 16.6 +/- 17.5 units per mg. protein). Mean expression in bladder tissues of controls was less than 2.3 units per mg. protein. CONCLUSIONS: These results suggest that angiogenic factors, such as PDEGF/TP and transforming growth factor-beta, may be involved in the inflammatory process to induce painful symptoms in patients with interstitial cystitis or bladder carcinoma. Proteoglycans such as CD44 may contribute to the presentation of these soluble angiogenic factors at the inflammation site.     

Polypeptide growth factors and the kidney: a developmental perspective

A variety of polypeptides with stimulatory or inhibitory effects on cell proliferation have been identified. In addition to stimulating or inhibiting the proliferation of cells and maintaining their viability, polypeptide growth factors play significant roles in embryogenesis and differentiation. The current review focuses on five specific polypeptide growth factor families (epidermal growth factor, insulin-like growth factors, transforming growth factors, platelet-derived growth factor, and fibroblast growth factors) and discusses their possible relationship to normal renal physiology, abnormal renal pathophysiology, and renal organogenesis. On the basis of current data, it is clear that polypeptide growth factors are multifunctional agents with important effects on renal function and renal organogenesis.     

Acute stress and intravesical corticotropin-releasing hormone induces mast cell dependent vascular endothelial growth factor release from mouse bladder explants

PURPOSE: Corticotropin-releasing hormone is typically released from the hypothalamus but it has proinflammatory effects outside of the brain, possibly through the activation of mast cells. These cells express corticotropin-releasing hormone receptors with selective secretion of vascular endothelial growth factor, which may be involved in the pathogenesis of painful bladder syndrome/interstitial cystitis. This condition is characterized by bladder inflammation and worsened by stress. We investigated the effect of intravesical corticotropin-releasing hormone and acute restraint stress on vascular endothelial growth factor release from mouse bladder explants and the role of mast cells. MATERIALS AND METHODS: The bladder of C57BL/6 mast cell deficient (W/W(v)) and normal congenic (+/+) female mice (Jackson Laboratories, Bar Harbor, Maine) at ages 10 to 12 weeks was catheterized using anesthesia. After emptying urine 1) normal saline or corticotropin-releasing hormone was introduced for 45 minutes, urine was collected and the mice were allowed to recover for 4 hours before sacrifice or 2) the mice were stressed by placing them in a restrainer for 4 hours before sacrifice and urine was collected 2 hours after stress. The bladder was removed 4 hours after stress and processed for corticotropin-releasing hormone immunohistochemical staining. In other experiments the bladder was removed, minced into 1 mm(2) pieces and cultured with or without corticotropin-releasing hormone overnight. Urine and medium were frozen for histamine, interleukin-6, tumor necrosis factor-alpha and vascular endothelial growth factor assay. RESULTS: Corticotropin-releasing hormone (100 nM) or acute restraint stress (4 hours) increased histamine release in urine and vascular endothelial growth factor release in medium without increasing interleukin-6 or tumor necrosis factor-alpha in the bladder explants of C57BL/6 or +/+ but not W/W(v) mice. No vascular endothelial growth factor, interleukin-6 or tumor necrosis factor-alpha was detected in urine before or after stimulation. Corticotropin-releasing hormone immunoreactivity was present in control bladders but it increased dramatically in the bladder of stressed mice. CONCLUSIONS: Intravesical corticotropin-releasing hormone and acute restraint stress induced mast cell dependent vascular endothelial growth factor release from bladder explants. These findings suggest that stress, corticotropin-releasing hormone, mast cells and vascular endothelial growth factor might participate in the pathogenesis of painful bladder syndrome/interstitial cystitis, which is worsened by stress, and provide for new therapeutic targets.