Sensitivity of bladder cancer cells to curcumin and its derivatives depends on the extracellular matrix

Because the response of cancer cells to chemotherapeutic agents depends upon the supporting extracellular matrix (ECM), the response in vivo may not be reproduced in 2-dimensional cell culture. The dose-response to curcumin and two derivatives by bladder cancer cells grown on both normal (SISgel) and cancer-derived ECM (Matrigel) and on plastic were contrasted. Cells grown on Matrigel were resistant to curcumins, but cells growing on SISgel, which mimic cancer cells suppressed by normal ECM, were nearly as sensitive as cells grown on plastic. SV40-immortalized urothelial cells, which are models for premalignant cells, were the most sensitive, but even aggressive cell lines were nearly as sensitive when grown on SISgel as on plastic. Curcumin response depends highly on the supporting ECM, and cells grown on plastic poorly models cells growing on natural ECM. Curcumin could prove an effective chemopreventive for bladder cancer recurrence when administered intravesically post-therapy.

Proteome-level display by 2-dimensional chromatography of extracellular matrix-dependent modulation of the phenotype of bladder cancer cells

Background

The extracellular matrix can have a profound effect upon the phenotype of cancer cells. Previous work has shown that growth of bladder cancer cells on a matrix derived from normal basement membrane suppresses many malignant features that are displayed when the cells are grown on a matrix that has been modified by malignant tumors. This work was undertaken to investigate proteome-level changes as determined by a new commercially available proteome display involving 2-dimensional chromatography for bladder cancer cells grown on different extracellular matrix preparations that modulate the expression of the malignant phenotype.

Results

Depending on the matrix, between 1300 and 2000 distinct peaks were detected by two-dimensional chromatographic fractionation of 2.1 – 4.4 mg of total cellular protein. The fractions eluting from the reversed-phase fractionation were suitable for mass spectrometric identification following only lyophilization and trypsin digestion and achieved approximately 10-fold higher sensitivity than was obtained with gel-based separations. Abundant proteins that were unique to cells grown on one of the matrices were identified by mass spectrometry. Following concentration, peaks of 0.03 AU provided unambiguous identification of protein components when 10% of the sample was analyzed, whereas peaks of 0.05 AU was approximately the lower limit of detection when the entire sample was separated on a gel and in-gel digestion was used. Although some fractions were homogeneous, others were not, and up to 3 proteins per fraction were identified. Strong evidence for post-translational modification of the unique proteins was noted. All 13 of the unique proteins from cells grown on Matrigel were related to MYC pathway.

Conclusion

The system provides a viable alternative to 2-dimensional gel electrophoresis for proteomic display of biological systems. The findings suggest the importance of MYC to the malignant phenotype of bladder cancer cells.

The inflammatory and normal transcriptome of mouse bladder detrusor and mucosa

Background

An organ such as the bladder consists of complex, interacting set of tissues and cells. Inflammation has been implicated in every major disease of the bladder, including cancer, interstitial cystitis, and infection. However, scanty is the information about individual detrusor and urothelium transcriptomes in response to inflammation. Here, we used suppression subtractive hybridizations (SSH) to determine bladder tissue- and disease-specific genes and transcriptional regulatory elements (TRE)s. Unique TREs and genes were assembled into putative networks.

Results

It was found that the control bladder mucosa presented regulatory elements driving genes such as myosin light chain phosphatase and calponin 1 that influence the smooth muscle phenotype. In the control detrusor network the Pax-3 TRE was significantly over-represented. During development, the Pax-3 transcription factor (TF) maintains progenitor cells in an undifferentiated state whereas, during inflammation, Pax-3 was suppressed and genes involved in neuronal development (synapsin I) were up-regulated. Therefore, during inflammation, an increased maturation of neural progenitor cells in the muscle may underlie detrusor instability. NF-κB was specifically over-represented in the inflamed mucosa regulatory network. When the inflamed detrusor was compared to control, two major pathways were found, one encoding synapsin I, a neuron-specific phosphoprotein, and the other an important apoptotic protein, siva. In response to LPS-induced inflammation, the liver X receptor was over-represented in both mucosa and detrusor regulatory networks confirming a role for this nuclear receptor in LPS-induced gene expression.

Conclusion

A new approach for understanding bladder muscle-urothelium interaction was developed by assembling SSH, real time PCR, and TRE analysis results into regulatory networks. Interestingly, some of the TREs and their downstream transcripts originally involved in organogenesis and oncogenesis were also activated during inflammation. The latter represents an additional link between inflammation and cancer. The regulatory networks represent key targets for development of novel drugs targeting bladder diseases.

Analysis of the interaction of extracellular matrix and phenotype of bladder cancer cells

Background

The extracellular matrix has a major effect upon the malignant properties of bladder cancer cells both in vitro in 3-dimensional culture and in vivo. Comparing gene expression of several bladder cancer cells lines grown under permissive and suppressive conditions in 3-dimensional growth on cancer-derived and normal-derived basement membrane gels respectively and on plastic in conventional tissue culture provides a model system for investigating the interaction of malignancy and extracellular matrix. Understanding how the extracellular matrix affects the phenotype of bladder cancer cells may provide important clues to identify new markers or targets for therapy.

Methods

Five bladder cancer cell lines and one immortalized, but non-tumorigenic, urothelial line were grown on Matrigel, a cancer-derived ECM, on SISgel, a normal-derived ECM, and on plastic, where the only ECM is derived from the cells themselves. The transcriptomes were analyzed on an array of 1186 well-annotated cancer derived cDNAs containing most of the major pathways for malignancy. Hypervariable genes expressing more variability across cell lines than a set expressing technical variability were analyzed further. Expression values were clustered, and to identify genes most likely to represent biological factors, statistically over-represented ontologies and transcriptional regulatory elements were identified.

Results

Approximately 400 of the 1186 total genes were expressed 2 SD above background. Approximately 100 genes were hypervariable in cells grown on each ECM, but the pattern was different in each case. A core of 20 were identified as hypervariable under all 3 growth conditions, and 33 were hypervariable on both SISgel and Matrigel, but not on plastic. Clustering of the hypervariable genes showed very different patterns for the same 6 cell types on the different ECM. Even when loss of cell cycle regulation was identified, different genes were involved, depending on the ECM. Under the most permissive conditions of growth where the malignant phenotype was fully expressed, activation of AKT was noted. TGFβ1 signaling played a major role in the response of bladder cancer cells to ECM. Identification of TREs on genes that clustered together suggested some clustering was driven by specific transcription factors.

Conclusion

The extracellular matrix on which cancer cells are grown has a major effect on gene expression. A core of 20 malignancy-related genes were not affected by matrix, and 33 were differentially expressed on 3-dimensional culture as opposed to plastic. Other than these genes, the patterns of expression were very different in cells grown on SISgel than on Matrigel or even plastic, supporting the hypothesis that growth of bladder cancer cells on normal matrix suppresses some malignant functions. Unique underlying regulatory networks were driving gene expression and could be identified by the approach outlined here.

Exogenous glycosaminoglycans coat damaged bladder surfaces in experimentally damaged mouse bladder

BACKGROUND

Interstital cystitis is often treated with exogenous glycosaminoglycans such as heparin, chondroitin sulphate (Uracyst), hyaluronate (Cystistat) or the semi-synthetic pentosan polysulphate (Elmiron). The mechanism of action is presumed to be due to a coating of the bladder surface to replace the normally present chondroitin sulphate and heparan sulphate lost as a result of the disease. This study used fluorescent labelled chondroitin sulphate to track the distribution of glycosaminoglycans administered intravesically to mouse bladder that had been damaged on the surface.

METHODS

The surfaces of mouse bladders were damaged by 3 mechanisms -- trypsin, 10 mM HCl, and protamine sulphate. Texas Red-labeled chondroitin sulphate was instilled into the bladders of animals with damaged bladders and controls instilled only with saline. Bladders were harvested, frozen, and sectioned for examination by fluorescence.

RESULTS

The normal mouse bladder bound a very thin layer of the labelled chondroitin sulphate on the luminal surface. Trypsin- and HCl-damaged bladders bound the labelled chondroitin sulphate extensively on the surface with little penetration into the bladder muscle. Protamine produced less overt damage, and much less labelling was seen, presumably due to loss of the label as it complexed with the protamine intercalated into the bladder surface.

CONCLUSION

Glycosaminoglycan administered intravesically does bind to damaged bladder. Given that the changes seen following bladder damage resemble those seen naturally in interstitial cystitis, the mechanisms proposed for the action of these agents is consistent with a coating of damaged bladder.

A novel multidrug resistance phenotype of bladder tumor cells grown on Matrigel or SIS gel

We have previously shown that growth of bladder carcinoma cell lines onto matrices such as Matrigel and small intestinal submucosal (SIS) gel cause distinct changes in cellular morphology and motility. In these studies, we found that bladder cells grown on Matrigel showed increased resistance to either doxorubicin or mitomycin-C whereas growth of cells in SIS gel caused either significant increases or little difference in drug resistance, depending on both the cells and the drug. Finally, it was found that this altered drug sensitivity is reversible with a finite half-life and is likely due to altered drug accumulation and/or cell cycle kinetics.

Abnormal expression of molecular markers for bladder impermeability and differentiation in the urothelium of patients with interstitial cystitis

PURPOSE

Despite a lack of consensus concerning the etiology of interstitial cystitis (IC) the loss of impermeability and other abnormalities of the urothelium are features of the disease. In this study the distribution of proteins involved with epithelial adhesion, cellular differentiation and bladder impermeability in urothelial biopsies were explored by the immunohistochemical assessment of E-cadherin, ZO-1, uroplakin and chondroitin sulfate.

MATERIALS AND METHODS

Biopsies obtained from 27 patients with IC and 7 controls were immediately fixed in formalin, immunohistochemically labeled for the described proteins and scored for protein expression, morphology and differentiation.

RESULTS

Only 3 IC samples appeared completely normal, while 24 of the 27 showed an abnormality in at least 1 marker and in 6 all 4 markers were abnormal. In patients vs controls findings were abnormal for uroplakin in 13 of 27 vs 1 of 7 (p = 0.085), for E-cadherin (over expressed) in 18 of 27 vs 0 of 7 (p = 0.0021), for ZO-1 in 11 of 27 vs 0 of 7 (p = 0.046) and for chondroitin sulfate in 15 of 27 vs 0 of 7 (p = 0.0054). The morphology/polarity score significantly correlated with ZO-1 (Pearson r = 0.3935, p = 0.0423) and chondroitin sulfate (Pearson r = 0.7079, p <0.0001) expression. Chondroitin sulfate and ZO-1 showed a high correlation with each other (Pearson r = 0.5587, p = 0.0025). Uroplakin and E-cadherin expression were independent of all other markers.

CONCLUSIONS

The findings reported strongly suggest abnormal differentiation in the IC bladder. The disruption of ZO-1 is similar to that reported in feline IC. Elevated E-cadherin may represent an adaptation to increased bladder permeability.

A model for 3-dimensional growth of bladder cancers to investigate cell-matrix interactions

Elucidating the mechanisms by which the phenotype of cancer cells is modulated by the extracellular matrix (ECM) potentially identifies mechanisms that could be exploited for cancer control. Three readily available bladder cancer cell lines of different aggressiveness were grown on a bioscaffold material (Small Intestine Submucosa: SIS) under a variety of media and nutrient schedules to determine the influence of epigenetic factors on phenotype. The aggressive TCCSUP and J82 lines displayed an invasive phenotype when fed twice weekly with medium containing 10% fetal calf serum (FCS), but grew as a layered, noninvasive structure when fed daily with the same nutrient. The papillary RT4 cells grew as a nearly normal appearing layered phenotype when fed with medium containing 10% FCS, regardless of the feeding schedule. The papillary phenotype appeared only when the fetal calf serum concentration was reduced to 1% and the cells were fed twice weekly. Immunohistochemical staining showed E-cadherin was detected in the nucleus of the TCCSUP line rather than on the cell periphery, thus, demonstrating that normalization of the TCCSUP line into a layered phenotype did not alter the fundamental dysregulation of the cadherin-B-catenin-cytoskeleton complex. In contrast, in the RT4 cells the biomarker was distributed discretely around the cell periphery in 10% fetal calf serum but in the nucleus in 1% fetal calf serum and twice weekly feeding. Modulating the phenotype of cancer cells from invasive to noninvasive through manipulation of matrix and nutrient components presents a model system for identifying the key factors involved in invasiveness and may identify new therapeutic targets and markers.

Gene expression profiling of inflammatory bladder disorders

Inflammation underlies all major bladder pathologies including malignancy and represents a defense reaction to injury caused by physical damage, chemical substances, micro-organisms or other agents. During acute inflammation, activation of specific molecular pathways leads to an increased expression of selected genes whose products attack the insult, but ultimately should protect the tissue from the noxious stimulus. However, once the stimulus ceases, gene-expression should return to basal levels to avoid tissue damage, fibrosis, loss of function, and chronic inflammation. If this down-regulation does not occur, tissue fibrosis occurs as a serious complication of chronic inflammation. Although sensory nerve and most cells products are known to be key parts of the inflammatory puzzle, other key molecules are constantly being described that have a role in bladder inflammation. Therefore, as the database describing the repertoire of inflammatory mediators implicated in bladder inflammation increases, the central mechanisms by which injury can induce inflammation, cell damage, and repair often becomes less rather than more clear. To make sense of the vast knowledge of the genes involved in the inflammatory response may require analysis of the patterns of change and the elucidation of gene networks far more than definition of additional members of inflammatory cascades. This review discuss the appropriate use of microarray technology, which promises to solve both of these problems as well as identifying key molecules and mechanisms involved in the transition between acute and chronic inflammation.

Matrix-dependent plasticity of the malignant phenotype of bladder cancer cells

The purpose of this study was to investigate the effect of cancer- and normal basement membrane-derived extracellular matrix to modulate the phenotype of bladder cancer cell lines. Five lines, varying in malignancy from papilloma to highly undifferentiated and invasive and immortalized human urothelial cells, were grown on two extracellular matrix preparations, Matrigel and SISgel. Matrigel represents matrix remodeled by malignancy while SISgel, obtained from small intestine submucosa (SIS), represents the normal matrix supporting differentiated cell growth. On Matrigel, regardless of the content of growth factors, the invasive lines displayed an invasive phenotype, while the low grade lines grew as papillary structures. In contrast, when the same cells were grown on SISgel, they grew as a layer of cells one to 5 cells thick, failed to invade, and expressed cell-surface E-cadherin. Unlike breast cancer cells, neutralization of beta 1, beta 4 and alpha 6 integrins altered cell-cell and cell-matrix adhesiveness but did not alter the phenotype. When invasive cells were grown on mixtures of SISgel and Matrigel, the phenotype changed gradually, not abruptly, indicating that factors within the gel reversibly alter the phenotypic expression of invasion. In summary, the phenotype of bladder cancer cells growing in tissue-like 3-dimensional culture is highly plastic, and malignant properties such as invasion and papillary growth can be suppressed by the matrix.

Mapping of the distribution of significant proteins and proteoglycans in small intestinal submucosa by fluorescence microscopy

Because small intestine submucosa (SIS) is a bioscaffold for tissue regeneration, we describe a method to analyze the material for growth peptides and for structural molecules. Immunofluorescence methods are described for relative quantification of abundant structural proteins. Additionally, a quantitative technique for comparison of the content of less abundant proteins in SIS was developed using the tyramide signal amplification (TSA) system that is applicable to paraffin-preserved tissue blocks. Frozen sections generally shredded when cut thinly enough to permit entry and washout of reagents. Five micrometer sections cut from paraffin blocks were immunolabeled for collagen, heparan sulfate proteoglycans (HSPG), FGF2, TGFbeta, and VEGF. Images of tissue sections were acquired by a linear image camera and quantified by densitometry after thresholding the signal to minimize nonspecific fluorescence. Immunohistochemistry was used to confirm the immunofluorescence methods. HSPG was widely distributed but concentrated in vessels. FGF2 was distributed diffusely and was associated with fibrous structures. VEGF was distributed mainly around vessels. TGFbeta was barely detectable above background. Collagen fibrils were distinctly present, and with a two-color fluorescence system, the distribution of components relative to collagen can be assessed. The anatomic structure of SIS is likely to play an important role in the regeneration of tissues, and factors in remnant vessels may facilitate penetration of the matrix along these avenues.

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.

Pan-cadherin as a high level phenotypic biomarker for prostate cancer

PURPOSE

High level phenotypic biomarkers such as cadherins are needed to identify individuals at risk for biologically active prostate cancer and determine which individuals with elevated prostate specific antigen or a prostate nodule are candidates for re-biopsy. Cadherins are a high level phenotypic biomarker associated with decreased cell adhesion, which is a cardinal event in carcinogenesis. Recently we reported that G-actin and tissue transglutaminase type II are potential biomarkers for prostate cancer. In this study we present cadherins as a potential third component of the biomarker profile.

MATERIALS AND METHODS

Prostate tissues from 38 patients with cancer and 33 controls with a 10-year prostate cancer-free followup were labeled for pan-cadherin by immunohistochemical testing. Immunoreactivity was quantified using a Pathology Workstation (Autocyte Inc., Elon College, North Carolina).

RESULTS

Visually benign glands from controls generally expressed cadherins, whereas regions of adenocarcinoma were generally negative. On quantitative immunohistochemistry 36 of 38 prostate cancer cases expressed a lower mean percent area positive for cadherin than the 19 benign prostatic hyperplasia and 14 prostatitis cases (odds ratio 978, 95% confidence interval 45 to 21,140, relative risk 18, 95% confidence interval 5 to 67, p <0.0001). Receiver operating characteristics analysis of immunohistochemical testing data showed that an optimal threshold of 7 produced 95% sensitivity and 100% specificity.

CONCLUSIONS

Quantitative down-regulation of cadherin expression in prostate cancer tissue sections is a strong biomarker for prostate cancer. Analysis of cadherin and other high level phenotypic biomarker expression in the premalignant field may provide additional diagnostic information to decide which patients need re-biopsy, more intensive monitoring or chemoprevention.

G-actin as a risk factor and modulatable endpoint for cancer chemoprevention trials

Because tumorigenesis is an ongoing process, biomarkers can be used to identify individuals at risk for bladder cancer, and treatment of those at risk to prevent or slow further progression could be an effective means of cancer control given accurate individual risk assessment. Tumorigenesis proceeds through a series of defined phenotypic changes, including those in genetically altered cells destined to become cancer as well as in surrounding normal cells responding to the altered cytokine environment. A panel of biomarkers for the changes can provide a useful system for individual risk assessment in cancer patients and in individuals exposed to carcinogens. The use of such markers can increase the specificity of chemoprevention trials by targeting therapy to patients likely to respond, and thereby markedly reduce the costs of the trials. Previous studies in our laboratories showed the cytoskeletal proteins G- and F-actin reflect differentiation-related changes in cells undergoing tumorigenesis and in adjacent "field" cells, and a pattern of low F-actin and high G-actin is indicative of increased risk. Actin changes may be a common feature in genetic and epigenetic carcinogenic mechanisms. In a group of over 1600 workers exposed to benzidine, G-actin correlated with exposure, establishing it as an early marker of effect. In another study, a profile of biomarkers was monitored in patients who underwent transurethral resection of bladder tumor (TURBT) and received Bacillus Calmette Guerin (BCG) and/or DMSO. The primary objective was to determine how the defined biomarkers expressed in the tumor and the field correlate with clinical response and recurrence. DMSO, known to modulate G-actin in vitro, was used as an agent. Results strongly support the hypothesis that cytosolic G-actin levels measured by quantitative fluorescence image analysis (QFIA) can be an important intermediate endpoint marker for chemoprevention and that the p300 (M344) and DNA ploidy markers identify a high-risk group that requires more aggressive therapy and recurrence monitoring. Further research with other markers has shown that DD23 and nuclear actin, both of which identify late, specific changes, may increase the battery of useful markers. Taken together these studies show how biomarkers are employed to study individuals at risk, aid in the selection of chemopreventive compounds and assist in the understanding of the pathogenesis of malignancy.

Biomarkers in monitoring for efficacy of immunotherapy and chemoprevention of bladder cancer with dimethylsulfoxide

This study correlated biomarkers expressed in tumor and epithelial field with clinical response and recurrence. Of 25 bladder cancer patients, 11 received 6 weeks of intravesical Bacille Calmette-Guerin (BCG), and 14 were treated weekly with intravesical dimethylsulfoxide (DMSO) for 4 weeks to further modulate biomarker expression. G-actin, DNA aneuploidy, and p300 tumor antigen were evaluated by quantitative fluorescence image analysis on uroepithelial cells from bladder wash samples prior to and immediately following treatment. Excluding patients who did not respond to BCG (and who had persistently abnormal p300 and DNA markers), recurrence correlated with persistent abnormal G-actin findings. Of patients who were G-actin negative following therapy, only 25% recurred during follow-up in contrast to 67% in patients who were positive (p < 0.03 by Fisher's exact test). The odds ratio for recurrence was 6.00 (95% confidence interval: 1.3-28.6). Cytosolic G-actin levels can be an important intermediate end point marker for chemoprevention.

Biomarker risk assessment and bladder cancer detection in a cohort exposed to benzidine

BACKGROUND

Cancer screening with highly sensitive, specific biomarkers that reflect molecular phenotypic alterations is an attractive strategy for cancer control. We examined whether biomarker profiles could be used for risk assessment and cancer detection in a cohort of Chinese workers occupationally exposed to benzidine and at risk for bladder cancer.

METHODS

The cohort consisted of 1788 exposed and 373 nonexposed workers, followed from 1991 through 1997. We assayed urothelial cells from voided urine samples for DNA ploidy (expressed as the 5C-exceeding rate [DNA 5CER]), the bladder tumor-associated antigen p300, and a cytoskeletal protein (G-actin). Workers were stratified into different risk groups (high, moderate, and low risk) at each examination based on a predefined biomarker profile. For workers who developed bladder cancer, tumor risk assessment was analyzed from samples collected 6-12 months before the cancer diagnosis. The associations between risk group and subsequent development of bladder cancer were analyzed by Cox proportional hazards regression analysis and logistic analysis, after adjustment. All statistical tests were two-sided.

RESULTS

Twenty-eight bladder cancers were diagnosed in exposed workers and two in nonexposed workers. For risk assessment, DNA 5CER had 87.5% sensitivity, 86.5% specificity, an odds ratio (OR) of 46.2 (95% confidence interval [CI] = 8.1 to 867.0), and a risk ratio (RR) of 16.2 (95% CI = 7.1 to 37.0); p300 had 50.0% sensitivity, 97.9% specificity, an OR of 40.0 (95% CI = 9.0 to 177.8), and an RR of 37.9 (95% CI = 16.8 to 85.3). The risk of developing bladder cancer was 19.6 (95% CI = 8.0 to 47.9) times higher in workers positive for either the DNA 5CER or p300 biomarkers than in workers negative for both biomarkers and 81.4 (95% CI = 33.3 to 199.3) times higher in workers positive for both biomarkers. G-actin was a poor marker of individual risk.

CONCLUSIONS

Occupationally exposed workers at risk for bladder cancer can be individually stratified, screened, monitored, and diagnosed based on predefined molecular biomarker profiles.

Abnormal G-actin content in single prostate cells as a biomarker of prostate cancer

The distribution of altered G-actin was investigated in prostatic cells obtained by fine needle aspiration (FNA) from 27 excised prostate glands obtained during radical prostatectomy. FNA, which was used to obtain single cells for image analysis, sampled in the region of any nodules and in grossly normal areas of the contralateral lobes. Quantitative fluorescence-image analysis was used to assay the amount of G-actin in individual cells. Abnormal G-actin, a precursor cytoskeletal protein representing cytoskeletal rearrangements accompanying cellular transformation, was associated with the presence of adenocarcinoma in 22 of 27 specimens from the dominant nodule, but only 3 of 20 in the grossly normal specimens (P<.0001). The mean G-actin content of all samples from the dominant nodule was 113.2+/-6.87 and 69.57+/-4.47 from the grossly normal area, the difference being significant at P<.0001. Altered G-actin was not associated with Gleason score (P = .95), grade (P = .26), stage (P = .058), or tumor volume (P = .32), thereby indicating it is a general marker for prostate adenocarcinoma.

Bexarotene ligand pharmaceuticals

Bexarotene (LGD-1069), from Ligand, was the first retinoid X receptor (RXR)-selective, antitumor retinoid to enter clinical trials. The company launched the drug for the treatment of cutaneous T-cell lymphoma (CTCL), as Targretin capsules, in the US in January 2000 [359023]. The company filed an NDA for Targretin capsules in June 1999, and for topical gel in December 1999 [329011], [349982] specifically for once-daily oral administration for the treatment of patients with early-stage CTCL who have not tolerated other therapies, patients with refractory or persistent early stage CTCL and patients with refractory advanced stage CTCL. The FDA approved Targretin capsules at the end of December 1999 for once-daily oral treatment of all stages of CTCL in patients refractory to at least one prior systemic therapy, at an initial dose of 300 mg/m2/day. After an NDA was submitted in December 1999 for Targretin gel, the drug received Priority Review status for use as a treatment of cutaneous lesions in patients with stage IA, IB or IIA CTCL [354836]. The FDA issued an approvable letter in June 2000, and granted marketing clearance for CTCL in the same month [370687], [372768], [372769], [373279]. Ligand had received Orphan Drug designation for this indication [329011]. At the request of the FDA, Ligand agreed to carry out certain post-approval phase IV and pharmacokinetic studies [351604]. The company filed an MAA with the EMEA for Targretin Capsules to treat lymphoma in November 1999 [348944]. The NDA for Targretin gel is based on a multicenter phase III trial that was conducted in the US, Canada, Europe and Australia involving 50 patients and a multicenter phase I/II clinical program involving 67 patients. Targretin gel was evaluated for the treatment of patients with early stage CTCL (IA-IIA) who were refractory to, intolerant to, or reached a response plateau for at least 6 months on at least two prior therapies. Efficacy results exceeded the protocol-defined response target rates; side effects were primarily limited to local skin reactions [349982]. Ligand has worldwide rights to market bexarotene capsules, and will market the drug in the US, Canada and selected European markets. In Spain, Portugal, Greece and Central and South America, Ferrer Internacional will market and distribute the drug. As of December 1999, Ligand was seeking additional distribution partners for select European and Asian markets [351604]. In January 2000, Alfa Wassermann signed an agreement with Ligand to exclusively market and distribute Targretin gel and capsules in Italy. Alfa paid US $0.75 million on signing with additional amounts up to an aggregate total of US $1.0 million on achievement of certain registration milestones, which are expected to be met in 2000 [351882].

Loss of tissue transglutaminase as a biomarker for prostate adenocarcinoma

BACKGROUND

Additional molecular tissue biomarkers for prostate carcinoma are needed to stratify patients with clinically suspicious findings, such as an elevated prostate specific antigen (PSA) with a negative biopsy, according to risk.

METHODS

Prostate tissues from 43 cancer cases and 47 controls with no evidence of cancer were labeled for transglutaminase by immunohistochemistry. Immunoreactivity was quantified using the Autocyte Pathology Workstation. In addition, quantitative fluorescence image analysis was used to compare transglutaminase concentrations in cells obtained by fine-needle aspiration from excised prostates. Loss of gene expression was evaluated by reverse transcriptase-polymerase chain reaction and growth with 5-azacytidine.

RESULTS

Visually, benign glands from controls generally expressed tissue transglutaminase, whereas regions with adenocarcinoma generally were negative. With quantitative immunohistochemistry, 41 of 43 adenocarcinoma of the prostate (CaP) cases expressed lower mean percentage areas positive for transglutaminase than did 30 of 30 benign prostatic hyperplasia (BPH) and 17 of 17 prostatitis cases (P < 0.0001; odds ratio [OR], 1577; 95% confidence interval (CI), 74-33, 820; relative risk [RR], 25; 95% CI, 6-95). Quantitative immunofluorescence of 3277 cells collected by FNA from 19 CaP cases and 645 cells from 5 cases of BPH showed that the mean content of transglutaminase was 93 femtograms (fg) for the CaP-derived cells and 138 fg for the BPH cells (P < 0.0001). Receiver operating curve analysis of the immunohistochemistry data showed an optimized threshold produced 95% sensitivity with 100% specificity. Growth of LNCaP cells with 5-azacytidine failed to stimulate transglutaminase expression, suggesting that loss of expression was likely not attributable to promoter methylation.

CONCLUSIONS

Measurements of transglutaminase on tissue sections provides additional diagnostic information that is potentially useful for risk assessment of patients with suspicious clinical findings, such as nodules or positive PSA and negative biopsies, without overdetecting disease.

Retinoid signaling in immortalized and carcinoma-derived human uroepithelial cells

This paper investigates the presence and functionality of retinoid signaling pathways in human urinary bladder carcinoma and SV40-immortalized uroepithelial cell lines. Only two of eight cell lines were proliferation-inhibited by 10 microM of either all-trans or 13-cis-retinoic acid. Transactivation of the CAT gene under control of a retinoid-responsive element demonstrated functionality of the signaling pathway in both sensitive cell lines and four of six resistant cell lines. Relative RT-PCR analysis of a panel of retinoid-responsive and inducible genes demonstrated changes in expression levels of all the genes in response to-retinoic acid treatment together with numerous aberrations dysregulations. We conclude that retinoid signaling may be a target for inactivation during tumorigenesis by uncoupling gene expression, proliferation and differentiation. Therefore retinoids are more likely to be effective for chemoprevention than for treatment of bladder carcinomas.

Complexity, Retinoid-Responsive Gene Networks, and Bladder Carcinogenesis

Carcinogenesis involves inactivation or subversion of the normal controls of proliferation, differentiation, and apoptosis. However, these controls are robust, redundant, and interlinked at the gene expression levels, regulation of mRNA lifetimes, transcription, and recycling of proteins. One of the central systems of control of proliferation, differentiation and apoptosis is retinoid signaling. The hRAR alpha nuclear receptor occupies a central position with respect to induction of gene transcription in that when bound to appropriate retinoid ligands, its homodimers and heterodimers with hRXR alpha regulate the transcription of a number of retinoid-responsive genes. These include genes in other signaling pathways, so that the whole forms a complex network. In this study we showed that simple, cause-effect interpretations in terms of hRAR alpha gene transcription being the central regulatory event would not describe the retinoid-responsive gene network. A set of cultured bladder-derived cells representing different stages of bladder tumorigenesis formed a model system. It consisted of 2 immortalized bladder cell lines (HUC-BC and HUC-PC), one squamous cell carcinoma cell line (SCaBER), one papilloma line (RT4), and 4 transitional cell carcinomas (TCC-Sup, 5637, T24, J82) of varying stages and grades. This set of cells were used to model the range of behaviors of bladder cancers. Relative gene expression before (constitutive) and after treatment with 10 microM all-trans-retinoic acid (aTRA) was measured for androgen and estrogen receptor; a set of genes involved with retinoid metabolism and action, hRAR alpha nd beta, hRXR alpha and beta CRBP, CRABP I and II; and for signaling genes that are known to be sensitive to retinoic acid, EGFR, cytokine MK, ICAM I and transglutaminase. The phenotype for inhibition of proliferation and for apoptotic response to both aTRA and the synthetic retinoid 4-HPR was determined. Transfection with a CAT-containing plasmid containing an aTRA-sensitive promoter was used to determine if the common retinoic acid responsive element (RARE)-dependent pathway for retinoid regulation of gene expression was active. Each of the genes selected is known from previous studies to react to aTRA in a certain way, either by up- or down-regulation of the message and protein. A complex data set not readily interpretable by simple cause and effect was observed. While all cell lines expressed high levels of the mRNAs for hRXR alpha and beta that were not altered by treatment with exogenous aTRA, constitutive and stimulated responses of the other genes varied widely among the cell lines. For example, CRABP I was not expressed by J82, T24, 5637 and RT4, but was expressed at low levels that did not change in SCaBER and at moderate levels that decreased, increased, or decreased sharply in HUC-BC, TCC-Sup and HUC-PC, respectively. The expression of hRAR alpha, which governs the expression of many retinoid-sensitive genes, was expressed at moderate to high levels in all cell lines, but in some it was sharply upregulated (TCC-Sup, HUC-PC and J82), remained constant (5637 and HUC-BC), or was down-regulated (SCaBER, T24 and RT4). The phenotypes for inhibition of proliferation showed no obvious relationship to the expression of any single gene, but cell lines that were inhibited by aTRA (HUC-BC and TCC-Sup) were not sensitive to 4-HPR, and vice versa. One line (RT4) was insensitive to either retinoid. Transfection showed very little retinoid-stimulated transfection of the CAT reporter gene with RT4 or HUC-PC. About 2-fold enhancement transactivation was observed with SCaBER, HUC-BC, J82 and T24 cells and 3-8 fold with 5637, TCC-Sup cells. In HUC-BC, a G to T point mutation was found at position 606 of the hRAR alpha gene. This mutation would substitute tyrosine for asparagine in a highly conserved domain. These data indicate that retinoid signaling is probably a frequent target of inactivation in bladder carcinogenesis. (ABSTRAC

Expression of retinoid-responsive genes occurs in colorectal carcinoma-derived cells irrespective of the presence of resistance to all-trans retinoic acid

BACKGROUND AND OBJECTIVES

Retinoids are metabolized in human intestinal epithelial cells to all-trans retinoic acid; however, it is unknown whether these cells express retinoid receptors, and whether sensitivity or resistance to the hormone is associated with a particular pattern of expression of retinoid-responsive genes.

METHODS

Northern blot analysis and reverse transcriptase polymerase chain reaction (RT-PCR) were used to identify mRNAs for retinoid receptors. Both Relative RT-PCR and transfection of retinoid-inducible plasmid were applied to test functionality of the pathway in a model system for colorectal carcinoma progression (primary SW480, all-trans retinoic acid-sensitive cells vs. metastatic SW620, -insensitive cells).

RESULTS

Three colorectal carcinoma-derived cell lines were inhibited by the hormone. Retinoic acid receptor type alpha (hRAR alpha) and retinoid X receptor type alpha (hRXR alpha) mRNAs were detected in normal enterocytes, colonocytes, and in all colorectal carcinoma-derived cells studied. Primary carcinomas and metastatic lesions expressed high amounts of hRAR alpha receptor protein, showing no simple correlation between the amounts of mRNA and receptor protein. No pattern of expression of the retinoid-responsive genes was associated with sensitivity or resistance to the retinoid. Expression of the genes occurred irrespective of resistance to the hormone or inactivity of the pathway.

CONCLUSIONS

Colonocytes possess a molecular system for transduction of the retinoid signal. All-trans retinoic acid modifies gene expression and inhibits proliferation of these cells. Therefore, retinoids are likely to be effective in chemoprevention of colorectal carcinoma.

Molecular study of sex steroid receptor gene expression in human colon and in colorectal carcinomas

BACKGROUND

Sex steroid hormones influence function of the human gastrointestinal tract. Although the specific receptor proteins have been identified in surgical specimens of both intestinal mucosa and colorectal carcinomas, it is still unknown whether they are expressed in intestinal epithelial cells.

METHODS

Expression of androgen receptor (AR) protein and estrogen receptor (ER) protein was studied by Scatchard analysis and ELISA (for ER only) in surgical specimens of normal-appearing mucosa, colorectal carcinomas, isolated colonocytes, and human colorectal carcinoma cell lines. Northern analysis was applied to identify the appropriate mRNAs, followed by the sensitive technique of reverse transcription-polymerase-chain-reaction (RT-PCR).

RESULTS

AR protein was identified in all surgical specimens analyzed and ER protein in 10 out of 13 normal-appearing mucosa specimens and 4 out of 7 colorectal carcinomas. The receptor proteins were not found in isolated colonocytes or in the transformed cell lines. RT-PCR confirmed that none of the isolated normal colonocytes or transformed colorectal carcinoma-derived cells expressed these mRNAs. Intestinal smooth muscle cells and fibroblasts were found to express sex steroid receptor mRNAs.

CONCLUSIONS

Both receptors are present in human large intestine but are expressed in stromal cells and not in intestinal epithelial cells. We hypothesize that sex steroids may influence the function of colonocytes indirectly through stromal-epithelial interactions.

Quantitative changes in cytoskeletal and nuclear actins during cellular transformation

Actin, a highly conserved protein comprising cell stress fibers and other cellular structures, is found in both the cytoplasm and nucleus of cells and responds to both epigenetic signals and altered gene expression occurring during tumorigenesis. We have previously shown that changes in the cytoplasmic F- and G-actin ratios reflect bladder cancer risk. To determine whether nuclear actin is also altered and how nuclear and cytoplasmic actin alterations are interrelated in transformation, an in vitro model of carcinogen-induced transformation consisting of 2 human uroepithelial cell lines immortalized by infection with SV-40 was studied. One line, HUC-PC, is tumorigenic in nude mice after incubation with the carcinogen 4-ABP, the other, HUC-BC, is not. Cytoplasmic and nuclear F- and G-actin were determined by QFIA on individual cells using fluorochrome-labeled phallicidin and DNase, I, respectively. Before exposure to 4-ABP, the PC cells had lower cytoplasmic F-actin content, higher cytoplasmic G-actin content, but similar levels of nuclear G- and F-actin in comparison to the BC cells. After incubation with 4-ABP, F-actin decreased and G-actin increased in both cytoplasm and nuclei of PC cells and cytoplasmic F-actin fibers were lost, but only cytoplasmic actin was altered in the BC cells. Northern blot analysis showed the expression of the beta-actin gene was only approximately 20% lower in 4-ABP-treated PC cells than in untreated controls, indicating the cellular change in actin was attributed to a shift between F- and G-actin proteins rather than to net actin synthesis.

Neural net-based identification of cells expressing the p300 tumor-related antigen using fluorescence image analysis

We report on preliminary investigations of the use of an image analysis system to perform preliminary algorithmic classification of images of fluorochrome-labeled cells followed by capture of gray-level images of potentially abnormal cells for analysis by a neural network. Cells were labeled with an antibody against a bladder cancer tumor-associated antigen, and the neural net was used to distinguish true-positive cells from negative cells, false-positive cells (autofluorescent or nonspecific labeling), and cell-sized artifacts. Gray-level cell images were digitized and processed for analysis by a feed-forward neural network using back-propagation. The network was trained and tested with two independent image sets. Various network configurations and activation functions were investigated, including a sinusoidal activation function. At high power, the network agreed completely with the human observer's classification. At low power, a strong clustering of cells classified by the network with expert classification was seen, while the neural network showed roughly 75% concordance with the human observer. In addition, a set of four features extracted from raw cell images were investigated. The features were: shape factor, texture, area, and average pixel intensity. A network trained with these features performed better than one operating with gray-level images. We conclude that using neural networks to recognize and classify images captured by an image analysis microscope is feasible.

Molecular study of sex steroid receptor gene expression in human colon and in colorectal carcinomas

BACKGROUND

Sex steroid hormones influence function of the human gastrointestinal tract. Although the specific receptor proteins have been identified in surgical specimens of both intestinal mucosa and colorectal carcinomas, it is still unknown whether they are expressed in intestinal epithelial cells.

METHODS

Expression of androgen receptor (AR) protein and estrogen receptor (ER) protein was studied by Scatchard analysis and ELISA (for ER only) in surgical specimens of normal-appearing mucosa, colorectal carcinomas, isolated colonocytes, and human colorectal carcinoma cell lines. Northern analysis was applied to identify the appropriate mRNAs, followed by the sensitive technique of reverse transcription-polymerase-chain-reaction (RT-PCR).

RESULTS

AR protein was identified in all surgical specimens analyzed and ER protein in 10 out of 13 normal-appearing mucosa specimens and 4 out of 7 colorectal carcinomas. The receptor proteins were not found in isolated colonocytes or in the transformed cell lines. RT-PCR confirmed that none of the isolated normal colonocytes or transformed colorectal carcinoma-derived cells expressed these mRNAs. Intestinal smooth muscle cells and fibroblasts were found to express sex steroid receptor mRNAs.

CONCLUSIONS

Both receptors are present in human large intestine but are expressed in stromal cells and not in intestinal epithelial cells. We hypothesize that sex steroids may influence the function of colonocytes indirectly through stromal-epithelial interactions.

Characterization of the DD23 tumor-associated antigen for bladder cancer detection and recurrence monitoring. Marker Network for Bladder Cancer

Bladder cancer detection, monitoring, and prevention represent major problems that could be addressed with sensitive and specific biomarkers. The antigen recognized by the DD23 antibody, previously developed against a tumor-related antigen, was partially biochemically characterized, and its sensitivity and specificity in cancer detection and recurrence monitoring was evaluated. Quantitative fluorescence image analysis was used to quantify antigen content in exfoliated urothelial cells in a cross-section of patients with bladder cancers of all grades and stages and control populations. The antigen was found in tumor cells as well as normal-appearing urothelial cells, suggesting it represents a marker induced by the altered growth factor environment of a cancer-containing bladder. When used as a quantitative marker, the sensitivity for bladder cancer detection was 85%, and the specificity was 95%. No significant difference was seen between symptomatic and asymptomatic control populations, including patients with previous bladder cancers in the absence of a recurrence. In bladder cancer recurrence monitoring, results were consistently negative until just before detection of a recurrence. The biomarker reflects a "field effect" that occurs very late in tumorigenesis and seems to represent events common to most cancers involving the genitourinary tract. Western blotting showed the antibody recognized a dimeric protein. DD23 quantification in single cells may be particularly useful in targeting cystoscopic intervention for recurrence monitoring and, because of its high specificity, could be a tool for bladder cancer screening in high-risk groups.

A deficit of chondroitin sulfate proteoglycans on the bladder uroepithelium in interstitial cystitis

OBJECTIVES

To investigate the abundance of chondroitin sulfate proteoglycans at the bladder lumenal and subepithelial surfaces in bladder biopsies derived from patients with interstitial cystitis (IC) and controls.

METHODS

Tissue sections derived from biopsies from 31 IC patients and 24 pathologically normal control sections were labeled for proteoglycans using the 2B6 anti-"stub" antibody and detected by immunohistochemistry.

RESULTS

On the lumenal surface, 5 of 31 (19%) IC sections were positive for proteoglycans versus 14 of 24 (58%) control sections (P = 0.00011). At the basal surface, 5 of 19 IC patients were positive versus 7 of 12 controls (P = 0.032).

CONCLUSIONS

A deficit of bladder lumenal and basal proteoglycans is associated with IC. The deficit in basal layer proteoglycans suggests an altered urothelial differentiation program. The lumenal deficit suggests that the charge-dependent exclusion of ions from the bladder surface is compromised in IC.

Identification of proteoglycans present at high density on bovine and human bladder luminal surface

The proteoglycans on the bladder luminal surface that have been implicated in producing impermeability of the urothelium were investigated. Large-scale isolation was effected with bovine bladder, and smaller scale identification was achieved with human bladder. Little difference was noted between bovine and human bladders. About 80 to 90% of the total surface glycosaminoglycan was bound as integral membrane proteins released with 4 M. guanidinium chloride. About 55% of the protein-bound glycosaminoglycan (proteoglycan) was heparan sulfate, 29% was chondroitin sulfate, and the remainder was either not identified or was dermatan sulfate. Four main proteoglycan species (molecular weight between 85 and 240 kD) were seen, with two minor components present. The proteoglycans were present at very high densities on bladder surface, being stacked 5 to 60 deep. This density of charge will produce a bound water layer that may explain the bladder impermeability.

Structure, function, and pathology of proteoglycans and glycosaminoglycans in the urinary tract

The roles of glycosaminoglycans and proteoglycans in the physiology of the urinary tract are reviewed. The structures of proteoglycans and glycosaminoglycans are reviewed together with their role in control of epithelial differentiation through stromal-epithelial interactions and as modulators of cytokines. Heparan sulfate proteoglycans appear to be important in maintaining selectivity of the kidney tubular basement membrane, and the majority of the glycosaminoglycan found in the urine appears to come from the upper tract. Evidence suggesting that a dense layer of glycosaminoglycans on the urothelial surface is important to maintaining urothelial impermeability is reviewed and new data showing a high density of proteoglycans on the lumenal surface of the urothelium is presented. The role of this layer in maintaining antibacterial adherence and impermeability was discussed together with data suggesting that failure of this layer is an etiologic factor in interstitial cystitis. A model of the bladder surface is also presented to illustrate the role of proteoglycans and exogenous glycosaminoglycans in the defenses of normal bladder lumen and the failure of these defenses in the interstitial cystitis bladder.

Bladder cancer risk assessment with quantitative fluorescence image analysis of tumor markers in exfoliated bladder cells

BACKGROUND

The detection of potentially highly curable low-grade bladder cancers by noninvasive techniques remains an unsolved problem. Conventional cytology detects such tumors with 50% sensitivity, and addition of DNA measurements to cytology only improves sensitivity incrementally. Tumor-associated antigens potentially offer an additional diagnostic marker.

METHODS

In this study, the M344 antibody against a tumor-associated antigen expressed mainly by low-grade tumor cells was tested for its sensitivity and specificity, alone and in combination with DNA ploidy and cytology. Voided urine samples from 69 asymptomatic control subjects, urines and bladder washings from 59 patients with cancer, and 195 symptomatic control patients were collected. Cells were double-labeled with M344 monoclonal antibody and Hoechst. Each case was blinded, and the number of positive cells was scored by two independent observers.

RESULTS

High-grade and low-grade transitional cell carcinomas (TCC) were detected with equal efficiency (78%, P < 0.001 versus symptomatic control patients). Urine samples proved higher specificity in detecting cancers. Patients being monitored for recurrence, but without current detectable cancer, were intermediates between control subjects and patients with cancer, suggesting that this marker also responds to dysplasia or field disease. Patients with outlet obstruction did not significantly differ from patients with previous TCC (P = 0.95). When combined with DNA ploidy measurements and cytology, the sensitivity for low-grade and high-grade tumors was 88% and 95%, respectively.

CONCLUSIONS

The M344 antibody potentially could improve the specificity and sensitivity of detection of low-grade bladder tumors in symptomatic and asymptomatic patients as well as monitoring for recurrence, therapeutic response, and assessment of individual risk.

Alterations in phenotypic biochemical markers in bladder epithelium during tumorigenesis

Phenotypic biochemical markers of oncogenesis and differentiation were mapped in bladder biopsies to investigate changes that occur in bladder tumorigenesis and to identify markers for increased bladder cancer risk. Touch preparations from biopsy specimens from 30 patients were obtained from tumors, the adjacent bladder epithelium, and random distant bladder epithelium. Markers, including DNA ploidy, epidermal growth factor receptor (EGFR), and oncoproteins, were quantified in individual cells by using quantitative fluorescence image analysis. Cluster analysis revealed the markers fell into three independent groups: (i) G-actin and EGFR; (ii) ploidy, cytology, and p185 (HER-2/neu oncoprotein) (ERBB2); and (iii) p300, a low-grade tumor antigen. Each marker displayed a gradient of abnormality from distant field to adjacent field to tumor. Different patterns for each marker suggested a developmental sequence of bladder cancer oncogenesis; G-actin was altered in 58% of distant biopsies (vs. 0/6 normals, P < 0.001), ploidy and cytology were altered in < 20% of distant fields and approximately 80% of tumors, and the other markers were intermediate. Patterns of EGFR and p185 suggest low-and high-grade tracks diverge early (P < 0.05 by Mann-Whitney U test for EGFR and ANOVA for p185). In conclusion, this study shows that a sequence of phenotypic changes accompanies development and progression of bladder cancers. Biochemical alterations in cells of the bladder field are often detectable before abnormal pathology, and markers previously thought to be limited to tumors were found in the field. The hierarchy of expression may be useful in identifying high-risk patients, assessing completeness of response to therapy, and monitoring and predicting recurrence.

Effect of exogenous heparin on anchorage-independent growth of fibroblasts induced by transforming cytokines

Heparin at concentrations below 100 micrograms/ml stimulated anchorage-independent growth of NRK 49F (normal rat kidney fibroblasts, American type culture collection) rat fibroblasts at suboptimal cytokine concentrations but inhibited it at higher heparin concentrations regardless of the cytokine concentration. Heparin did not stimulate growth above that seen at optimal cytokine concentrations, suggesting that it alters the cellular response to the cytokines. These data suggest natural protein-glycosaminoglycan interactions play a role in modulating or mediating the actions of transforming cytokines and suggest they may play a role in acquisition of the transformed phenotype.

Urinary glycosaminoglycan excretion as a laboratory marker in the diagnosis of interstitial cystitis

Urinary macromolecular uronate and glycosaminoglycan uronate concentrations were determined in 209 urine specimens obtained from 192 interstitial cystitis patients, 47 asymptomatic normal individuals and 32 spinal cord injury patients. As a group the concentration of macromolecular uronate or glycosaminoglycan uronate was significantly less in the interstitial cystitis patients than in the normal controls. Some interstitial cystitis patients showed low values of macromolecular uronate and glycosaminoglycan uronate. Analysis of the population distributions suggested that macromolecular uronate may have significant value in diagnosis of interstitial cystitis.

Intermediate endpoint biomarkers for chemoprevention

The understanding of intermediate endpoint biomarker expression in relation to the sequential events in bladder tumorigenesis establishes a useful approach for evaluating chemopreventive agents. Biomarkers may be genotypic or phenotypic and function as biomarkers of susceptibility, exposure, effect, or disease. This paper reviews several years of research on biomarkers and their use in monitoring chemoprevention therapy. In initial animal experiments, mice were dosed with N-butyl-N-(4-hydroxybutyl)nitrosamine (OH-BBN) while co-administering N-(4-hydroxyphenyl)retinamide (4-HPR). 4-HPR did not statistically reduce tumor incidence, but did affect tumor differentiation and, consequently, nuclear size and DNA ploidy. These results suggest that nuclear size and ploidy may function as intermediate endpoint biomarkers of effect for oncogenesis and that epigenetic as well as genetic mechanisms may be primary in the oncogenic process. Early biomarkers of effect which occur prior to genetic effects or chromosome aberration may portend a higher probability of being modulated by differentiating agents such as retinoids. In vitro studies demonstrated that RPMI-7666 cells cultured with a phorbol ester tumor promoter (12-O-tetradecanoyl-phorbol-13-acetate) could be redifferentiated with 13-cis-retinoic acid and dimethyl sulfoxide (DMSO). F-actin, a cytoskeletal biomarker with a presumed function in the epigenetic mechanisms of carcinogenesis, could also be normalized in HL-60 cells treated with 4-HPR or DMSO. A clinical evaluation of F-actin in patients with varying degrees of risk confirmed the value of F-actin as a differentiating biomarker useful for bladder cancer risk assessment. The clarification of when the phenotypic changes of F-actin occur in the oncogenic process was achieved when a variety of biochemical changes were mapped in the patients with bladder cancer. These studies confirmed that G-actin, a reciprocal form of F-actin, is increased relatively early in bladder cancer oncogenesis when multiple biomarkers are quantitated in the field, adjacent area, and the tumor. Comparison of each individual biomarker's expression from field, adjacent to tumor, and tumor, and subsequent cluster analysis of these biomarkers, indicated that the possible sequence of phenotypic expression of biomarkers in bladder cancer oncogenesis is from G-actin, to p300 antigen, to epidermal growth factor receptor (EGFR), to p185 (neu oncogene product), to DNA aneuploidy and, finally, to visual morphology.(ABSTRACT TRUNCATED AT 400 WORDS)

Identification of a high risk subgroup of grade 1 transitional cell carcinoma using image analysis based deoxyribonucleic acid ploidy analysis of tumor tissue

The use of deoxyribonucleic acid (DNA) cytometry to identify a subset of patients with grade 1, stage Ta or T1 transitional cell carcinoma at high risk for death or recurrence was investigated in a retrospective study using paraffin blocks from 88 low grade transitional cell carcinomas of the bladder with an absorptiometric video-based image analysis system. Tumors were evaluated for ploidy (70 diploid, 16 aneuploid and 2 tetraploid) and the presence of cells with greater than 5C DNA. Survival analysis of 62 patients with adequate followup (15 to 20 years) showed that 43 of 62 (69%) suffered recurrences and 13 (21%) died of bladder cancer. The single most important predictors of death and recurrence were stem line aneuploidy and the presence of cells with greater than 5C DNA, respectively.

Quantitative fluorescence image analysis of deoxyribonucleic acid ploidy in urine from normal children

Quantitative fluorescence image analysis incorporates the 2 diagnostic techniques of cytological analysis with quantitation of deoxyribonucleic acid (DNA). Exfoliated urinary cells are ideal for analysis by this method, which allows the identification of "rare event" abnormal cells. We evaluated the urine from 50 children who had undergone cystoscopy or were catheterized for other reasons. The urine was free of infection by urinalysis. Cytological analysis demonstrated normal or atypical cells in all patients. Of the patients 1 (2%) had greater than 2 of 500 cells analyzed with greater than 5C DNA and 4 (8%) had greater than 2 of 500 cells with greater than 5C double stranded nucleic acid. These data suggest that it may be "normal" for urine to contain "rare event" abnormal cells. The significance of this finding is unclear at present.

Cellular F-actin levels as a marker for cellular transformation: correlation with bladder cancer risk

Previous findings in cultured cells that differentiated cells had markedly higher F-actin levels than undifferentiated cells (Cancer Res., 50: 2215-2220, 1990) suggested that quantitative F-actin measurements in urinary cells might provide diagnostic or prognostic information by identifying those individuals with cells tending towards a lower degree of differentiation. The feasibility of such an approach was investigated using a risk stratification schema. Bladder wash samples were obtained from 163 symptomatic patients being evaluated for bladder cancer and 41 asymptomatic controls without hematuria or other symptoms consistent with bladder cancer. F-actin levels were evaluated by flow cytometry using a fluorescent phalloidin probe. The risk of bladder cancer was stratified according to biopsy, either DNA ploidy by flow cytometry or quantitative fluorescence image analysis cytology, previous bladder cancer history, and hematuria. A strong correlation between the presence of cells with abnormally low F-actin content in cells obtained by bladder wash from 38 patients and biopsy-proved bladder transitional cell carcinoma (P less than 0.001) was observed. A strong correlation was also observed between the presence of cells with low F-actin content and risk of bladder cancer assessed by either stratification schema (P less than 0.0001). The correlation was more consistent with the stratification by quantitative fluorescence image analysis cytology because of the 37% false-positive rate of ploidy analysis by flow cytometry among the control patients. Further evidence that low F-actin was correlated with cellular abnormality was obtained from simultaneously labeling cells for F-actin and with M344 antibody, a monoclonal antibody against a low-grade bladder tumor-related antigen. These studies showed that the F-actin content of the M344-positive cells was lower than that of the M344-negative cells. These results suggest that F-actin could be an early and sensitive marker for bladder cancer detection and risk prognostication.

Molecular and cellular biological approaches and techniques in the detection of bladder cancer and enhanced risk for bladder cancer in high-risk groups

Recent advances in molecular cell biology, immunology, and toxicology enhance detection of actual and incipient disease and the definition of risk. Tumor-associated antigens may greatly improve detection of low-grade tumor cells. Several new strategies depend upon detecting molecular lesions of the genes controlling cell growth (oncogenes) at either the gene or protein levels. Highly sensitive techniques detecting DNA adducts are refining the ability to detect specific DNA damage shortly after exposure. The recognition of controls that actively stop proliferation (tumor suppressor genes), regulate differentiation or of relationships between metabolism and carcinogenesis may lead to new ways to identify persons genetically at increased risk from carcinogenic exposure. Current technologies, those on the near horizon, and long-term research needs are analyzed critically in terms of screening objectives.

Quantitative fluorescence image analysis in bladder cancer screening

Quantitative fluorescence image analysis (QFIA) cytology combines image analysis to measure DNA with visual cytology for bladder cancer detection. QFIA sensitivity is 76% to 81% and 95% to 100% for low- and high-grade tumors respectively, with 94% specificity in asymptomatic controls. QFIA screening of 504 persons within a beta-naphthylamine exposed cohort found DNA hyperploidy correlated with the duration of carcinogenic exposure and smoking history; marker prevalence was 23% for exposed workers who smoked and 2% for nonexposed nonsmokers. In prospective animal studies, QFIA was useful in monitoring carcinogenesis and chemoprevention with retinoids. Current QFIA research focuses on measurements of oncogenes, growth factors and their receptors, cytoskeleton, and tumor-associated antigens to improve sensitivity and specificity to low-grade tumors and to identify premalignant conditions. Profiles of biochemical and immunological markers on single cells may further assist in the study of high-risk cohorts and individual risk assessment.