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

"SMART" cytology: The next generation cytology for precision diagnosis

Cytology plays an important role in diagnosing and managing human diseases, especially cancer, as it is often a simple, low cost yet effective, and non-invasive or minimally invasive diagnostic tool. However, traditional morphology-based cytology practice has limitations, especially in the era of precision diagnosis. Recently there have been tremendous efforts devoted to apply computational tools and to perform molecular analysis on cytological samples for a variety of clinical purposes. Now is probably the appropriate juncture to integrate morphology, machine learning, and molecular analysis together and transform cytology from a morphology-driven practice to the next level - "SMART" Cytology. In this article we will provide a rather brief review of the relevant works for computational analysis on cytology samples, focusing on single-cell-based multiplex quantitative analysis of biomarkers, and introduce the conceptual framework of "SMART (Single cell, Multiplex, AI-driven, and Real Time)" Cytology.

Advances in Imaging Modalities, Artificial Intelligence, and Single Cell Biomarker Analysis, and Their Applications in Cytopathology

Several advances in recent decades in digital imaging, artificial intelligence, and multiplex modalities have improved our ability to automatically analyze and interpret imaging data. Imaging technologies such as optical coherence tomography, optical projection tomography, and quantitative phase microscopy allow analysis of tissues and cells in 3-dimensions and with subcellular granularity. Improvements in computer vision and machine learning have made algorithms more successful in automatically identifying important features to diagnose disease. Many new automated multiplex modalities such as antibody barcoding with cleavable DNA (ABCD), single cell analysis for tumor phenotyping (SCANT), fast analytical screening technique fine needle aspiration (FAST-FNA), and portable fluorescence-based image cytometry analyzer (CytoPAN) are under investigation. These have shown great promise in their ability to automatically analyze several biomarkers concurrently with high sensitivity, even in paucicellular samples, lending themselves well as tools in FNA. Not yet widely adopted for clinical use, many have successfully been applied to human samples. Once clinically validated, some of these technologies are poised to change the routine practice of cytopathology.

RNA interference suppressing PLCE1 gene expression decreases invasive power of human bladder cancer T24 cell line

Mutational activation of the ras proto-oncogenes is frequently found in cancers. The phospholipase C epsilon gene (PLCE1) encodes a novel ras-related protein (R-Ras) effector mediating the effects of R-Ras on the actin cytoskeleton and membrane protrusion, because R-Ras is coprecipitated with the PLCE1 protein and can increase its activity. The nature of downstream signaling pathways from Ras involved in bladder cancer remains poorly understood. We aimed to construct a small hairpin RNA (shRNA) expression plasmid against the PLCE1 gene and to observe the inhibition of human bladder carcinoma cell T24 migration by RNA interference suppressing the expression of PLCE1. Two PLCE1 plasmids (P1 and P2) were constructed and inserted into T24 cells. Reverse transcriptase-polymerase chain reaction and Western blot analyses were performed to investigate inhibition of PLCE1 expression after plasmid transfection. Invasive power of the T24 cell line was measured before and after transfection by a membrane invasion culture system (transwell chamber), gelatin enzymography, and immunocytochemistry of cells. The RT-PCR analysis of BCL2 mRNA levels among different groups of T24 cell line indicated that expression of BCL2 mRNA was lower in the two positive plasmid-transfected cell groups than in the blank control or HK-A groups. Silencing of PLCE1 might downregulate the level of MMP and BCL2 gene expression, decreasing the invasive power of bladder cancer T24 cells and thus inhibiting tumor development.

Activation of RAS family genes in urothelial carcinoma

PURPOSE

Bladder cancer is the fifth most common malignancy in men in Western society. We determined RAS codon 12 and 13 point mutations and evaluated mRNA expression levels in transitional cell carcinoma cases.

MATERIALS AND METHODS

Samples from 30 human bladder cancers and 30 normal tissues were analyzed by polymerase chain reaction/restriction fragment length polymorphism and direct sequencing to determine the occurrence of mutations in codons 12 and 13 of RAS family genes. Moreover, we used real-time reverse transcriptase-polymerase chain reaction to evaluate the expression profile of RAS genes in bladder cancer specimens compared to that in adjacent normal tissues.

RESULTS

Overall H-RAS mutations in codon 12 were observed in 9 tumor samples (30%). Two of the 9 patients (22%) had invasive bladder cancer and 7 (77%) had noninvasive bladder cancer. One H-RAS mutation (11%) was homozygous and the remaining 89% were heterozygous. All samples were WT for K and N-RAS oncogenes. Moreover, 23 of 30 samples (77%) showed over expression in at least 1 RAS family gene compared to adjacent normal tissue. K and N-RAS had the highest levels of over expression in bladder cancer specimens (50%), whereas 27% of transitional cell carcinomas demonstrated H-RAS over expression relative to paired normal tissues.

CONCLUSIONS

Our results underline the importance of H-RAS activation in human bladder cancer by codon 12 mutations. Moreover, they provide evidence that increased expression of all 3 RAS genes is a common event in bladder cancer that is associated with disease development.

Role of urinary cathepsin B and L in the detection of bladder urothelial cell carcinoma

PURPOSE

We tested the hypothesis that urinary cathepsin B and L are associated with bladder cancer recurrence and invasiveness in patients with a history of nonmuscle invasive urothelial carcinoma of the bladder.

MATERIALS AND METHODS

Cathepsin B and L, and NMP22 were determined in the urine specimens of 188 consecutive subjects with a history of treated urothelial carcinoma of the bladder, 31 with noncancerous urological conditions and 10 healthy subjects. Cathepsin B and L were analyzed as continuous and categorical variables based on their quartile distribution.

RESULTS

Urinary cathepsin L was higher in the 122 patients with cystoscopic evidence of bladder tumor compared with levels in 107 with normal cystoscopy (median 5.9, IQR 4.4 vs 3.0, IQR 3.2, p <0.001). Higher levels of cathepsin L were associated with positive cytology assay results, higher NMP22 and T1 or greater pathological stage (each p <0.001). Area under the ROC curves of NMP22 and cathepsin L for bladder cancer detection were 0.704 (95% CI 0.637-0.772) and 0.793 (95% CI 0.736-0.850), respectively. On multivariate analysis cathepsin L, NMP22 and cytology were associated with invasive pathological stage (OR 1.29, 2.42 and 2.76, respectively, p </=0.002). Urinary cathepsin B was not associated with any outcome variables.

CONCLUSIONS

Urinary cathepsin L is an independent predictor of bladder cancer presence and invasiveness in patients with a history of urothelial carcinoma of the bladder. Further evaluation of this marker is necessary before its use as an adjunct to cystoscopy for urothelial carcinoma of the bladder.

uCyt+ test: Alternative to cystoscopy for less-invasive follow-up of patients with low risk of urothelial carcinoma

OBJECTIVES

To assess the utility of ImmunoCyt/uCyt+ in combination with cytology to reduce the number and cost of cystoscopies in the follow-up of patients with urothelial cancer of the bladder.

METHODS

A total of 216 patients under follow-up after transurethral resection of the bladder for urothelial cancer were enrolled in the present study. The mean follow-up time was 26 months (range 3 to 96). Patients were tested for bladder cancer with ImmunoCyt/uCyt+, urinary cytology, and cystoscopy every 3 months. All patients with positive cystoscopy results for recurrence or suspect areas underwent transurethral resection of the bladder. Cystoscopy was considered the reference standard to establish the bladder tumor diagnosis. The patients were divided into low, intermediate, and high risk groups for progression according to the European Association of Urology criteria.

RESULTS

A total of 195 patients were suitable for evaluation. The urine samples from 21 patients were considered not evaluable for ImmunoCyt/uCyt+, and those patients were excluded from the study. Of all the control patients, 69.7% had negative cystoscopy findings. In the low-risk group, 84 patients underwent 131 cystoscopies, which diagnosed 30 Stage pTaG1 recurrences but no progression. Cytology and ImmunoCyt/uCyt+ together had a sensitivity of 86.6% and a negative predictive value of 95.2%.

CONCLUSIONS

Of the cystoscopies performed during the 26 months of follow-up, 69.7% were negative. In the low-risk group, 30 Stage pTaG1 tumors and no progression was detected at a total cost of 14,672 Euros (USD 17,606). ImmunoCyt/uCyt+ and cytology every 6 months combined with annual cystoscopy reduced the morbidity and cost of follow-up in this group.

Cytokeratin-20 and seminal vesicle secretory protein VI as possible marker proteins in urinary bladder preneoplastic lesions induced by N-butyl-N-(4-hydroxybutyl) nitrosamine

BACKGROUND

A simple and non-invasive methods for the diagnosis of transitional cell carcinoma of the bladder are needed for the prevention of invasive tumor. A proteomic technology has recently been developed to facilitate protein profiling of biological mixtures. We tried to detect the marker proteins by proteomic approach during the initiation stages on N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN)-induced bladder carcinogenesis in rats.

METHODS

Ten rats in group A were given 0.05% BBN in drinking water for 12 weeks. Other 10 rats in group B with 10 rats were designated as a control group and were not given BBN. Whole urinary bladders of all rats were excised at 12 weeks from the beginning of the experiment. Conventional proteomics was performed with high resolution 2-dimension gel electrophoresis followed by computational image analysis and protein identification using mass spectrometry.

RESULTS

A comparison of urinary bladder hyperplasia tissue with control tissue showed that five proteins; actin gamma2 propeptide, cytokeratin-20 (CK-20), proapolipoprotein, alpha2 actin (alpha-cardiac actin) and heat shock 27 kDa protein-1 were over-expressed in hyperplastic tissues. Three proteins; transcription factor myocardin, seminal vesicle secretory protein VI (SVS-VI) precursor and hypothetical protein RMT-7 were under-expressed in hyperplastic tissues.

CONCLUSION

In our animal mode, BBN-induced urinary bladder mucosal hyperplasia resulted in an increase in the expression of five proteins and a decrease in the expression of three proteins. Of these, CK-20 and SVS-VI seem to be of particular interest. However other method such as Western blotting seems to be needed for confirmation of these proteins and more information on human bladder tissue is needed for clinical application.

Comparison of cytokeratin 20 RNA and angiogenin in voided urine samples as diagnostic tools for bladder carcinoma

BACKGROUND

We evaluated the diagnostic efficacy of urinary angiogenin (ANG) and cytokeratin 20 (CK-20) mRNA in comparison with voided urine cytology in the detection of bladder cancer patients.

OBJECTIVES AND METHODS

A total of 97 Egyptian patients provided a single voided urine sample for ANG, CK-20 and cytology before cystoscopy. Of the 97 cases, 63 were histologically diagnosed as bladder cancer; 33 with transitional cell carcinoma (TCC) and 30 with squamous cell carcinoma (SCC), whereas the remaining 34 had benign urological disorders. A group of 46 healthy volunteers were also included in this study. Voided urine was centrifuged and the supernatant was used for estimation of ANG by EIA and confirmed by Western blotting (WB). The urine sediment was used for cytology and RNA extraction. CK-20 RNA was detected by RT-PCR.

RESULTS

The best cutoff value for ANG was calculated by a ROC curve as 322.7 ng/mg protein. The median urinary ANG level in bladder carcinoma, benign urological disorders and healthy volunteer groups was: 802.7, 425 and 33 pg/mg protein, respectively. The positivity rate for urinary CK-20 mRNA of the control, benign and malignant groups was 0%, 2.9% and 82.3%, respectively (P = 0.000); while the rates for ANG were 11.6%, 54.8% and 75.4%, respectively (P = 0.000). There was no significant difference in positivity rates of CK-20 and ANG with respect to sex, smoking, schistosomiasis, urine cytology, tumor grade, tumor stage, hematuria or pus cells. The overall sensitivity and specificity were 71.4% and 90% for voided urine cytology, 75.4% and 70.3% for ANG, and 82.3% and 98.8% for CK-20. Combined sensitivity of voided urine cytology with ANG and CK-20 together (98.2%) was higher than either the combined sensitivity of voided urine cytology with ANG (96.5%) or with CK-20 (91.6%) or than that of the biomarker alone. We demonstrated significant positive correlation between CK-20 positivity with age (P = 0.043) and nodal involvement (P = 0.037); however, there was no significant correlation between CK-20 and ANG with the other clinicopathological parameters.

CONCLUSIONS

Our data indicate that CK-20 and ANG in voided urine had higher sensitivities compared to voided urine cytology. However, when specificity was considered, CK-20 alone had superior sensitivity and specificity compared to ANG and voided urine cytology.

Detection of mucin 7 gene expression in exfoliated cells in urine from patients with bladder tumor

OBJECTIVES

To determine whether mucin (MUC) 7 gene expression can be used as a bladder tumor marker for transitional cell carcinoma in patients with bladder carcinoma.

METHODS

Cells from the urine of 65 patients with bladder cancer, 15 patients with a negative bladder biopsy for bladder cancer, and 30 healthy volunteers were compared for the following parameters: tumor stage, grade, size, and number, urinary cytology, and expression of MUC7. Nested reverse transcriptase-polymerase chain reaction (RT-PCR) was used to determine MUC7 expression (348 base pairs).

RESULTS

MUC7 in the urine samples of the control group was negative (no false-positive results, specificity 100%). Among the 15 patients with nonmalignant disease, MUC7 was negative in 13 (specificity 87%). In the 2 patients with positive MUC7, the histologic examination showed chronic inflammation. Among the 65 patients with bladder transitional cell carcinoma, MUC7 was positive in 44 (68%). Nested RT-PCR for MUC7 was positive in 25 (61%) of 41 with superficial stages (pTa and pT1) versus 16 (76%) of 21 patients with Stage pT2 or advanced stages. Nested RT-PCR for MUC7 was positive in 5 (42%) of 12 patients with grade 1 disease, 22 (65%) of 34 patients with grade 2 disease, and 17 (89%) of 19 patients with grade 3 disease. We demonstrated no correlation between MUC7 and the clinicopathologic features (tumor stage, grade, or size) of urinary bladder tumors.

CONCLUSIONS

Our results indicate that MUC7 is a potential marker for bladder cancer. This noninvasive detection method assesses urothelial cells from voided urine specimens using RT-PCR.

[Non-invasive urinary diagnosis of bladder cancer. What do we know?]

Although the current system of classifying bladder cancer by stage and histological grade is very useful, it is still difficult to predict the natural progression of the disease either with or without therapy. Cystoscopy and urine cytology are currently the gold standards in the monitoring and diagnosis of bladder cancer. Classical urine cytology is, however, at least in the diagnosis of G1-tumors, characterized by a relatively low sensitivity. In the last few years, the molecular biological investigation of the basic mechanisms involved in carcinogenesis has provided a host of markers which are of potential diagnostic value for bladder cancer. We provide a current, comprehensive review of the literature on bladder tumor markers and summarize their diagnostic and prognostic potential. At present, no diagnostic marker with a comparable sensitivity and specificity to cystoscopy exists, given that cystoscopy has never been evaluated. The combined analysis of several tumor markers seems to be the most promising approach as an adjunct to cystoscopy. Moreover, the increasing simplification of test systems will increase their acceptance by clinicians.

[The role of tumor markers in urologic consultation for screening, diagnosis, and follow-up of bladder cancer]

PURPOSE

Review the tumor markers for screening and diagnosis of transitional cell carcinoma of the bladder.

METHODS

The published literature on bladder cancer markers was identified using a MEDLINE search and critically analyzed. The sensitivity and specificity of the various markers were compared.

RESULTS

Conventional non-invasive methods for diagnosis (symptoms and urine cytology) and for screening and follow-up of transitional cell carcinoma of the bladder are not very sensitive and must not be considered sufficient. Some tumor markers seem to be a good alternative to the routine urinary cytology.

CONCLUSION

The role of tumor markers for screening and follow-up of bladder tumors as an alternative to cytology deserve consideration. In the future, more sensitive and specific markers may replace routine cystoscopy.

The Drake Health Registry Study: findings from fifteen years of continuous bladder cancer screening

BACKGROUND

The Drake Health Registry Study (DHRS) is an ongoing bladder cancer screening program initiated in 1986 due to workers' probable past exposure to the bladder carcinogen, beta-naphthylamine (BNA).

METHODS

At periodic screening visits, a health survey is administered and three screening tests are applied to a urine sample, urinalysis (UA), papanicolaou (PAP), and quantitative fluorescence image analysis (QFIA). Positive screens are eligible for a free bladder cystoscopy with random biopsies.

RESULTS

Forty of 51 persons eligible for diagnostic evaluation underwent cystoscopy. One person was diagnosed with carcinoma in situ, two with transitional cell papilloma, 14 with dysplasia, two of which developed transitional cell carcinoma; 26 had bladder abnormalities such as chronic inflammation, chronic cystitis, atypical changes, atypia, hyperplasia, or papillary clusters.

CONCLUSIONS

The DHRS continues to identify early stage bladder cancer and other abnormalities among workers exposed to BNA before 1981 and generates useful clinical, psycho-social, and epidemiologic data.

Urine: beyond cytology for detection of malignancy

In the present review we discuss various ancillary modalities for detection of malignancies in urine samples, with an emphasis on urothelial carcinomas. Flow cytometry, bladder tumor antigen (BTA), nuclear matrix protein (NMP), matrix metalloproteinase (MMP), human chorionic gonadotrophic (HCG), telomerase, and other techniques are discussed. DNA FCM is a relatively costly and sophisticated technique. It has a practical application in the diagnosis of bladder cancer among subjects at high risk and is of value in monitoring the course of the disease and anticipating recurrence following conservative treatment. The BTA test is a simple, rapid, and inexpensive adjunct to cystoscopy and the results of the test are equivalent or superior to those of voided urinary cytology. NMP-22 immunoassay is a useful diagnostic test for predicting recurrence of urothelial malignancy. It is also a cost-effective and sensitive screening test for detecting tumor in patients with urothelial carcinoma. Beta-HCG estimation in urine samples appears to be an efficient diagnostic marker for the assessment of distant metastasis in bladder carcinoma rather than a screening test. Other ancillary techniques such as detection of expression of cytokeratin 20 by RT-PCR, MMP-9 estimation, and fluorescent in situ hybridization and telomerase activity are rarely applied clinically in routine urinary samples and are not cost-effective.

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.

The BTA stat test is nonspecific for hematuria: an experimental hematuria model

PURPOSE

An experimental hematuria model was designed to determine whether the bladder tumor antigen (BTA) stat test (Bion Diagnostics, Redmond, Washington) is influenced by microscopic or macroscopic hematuria.

MATERIALS AND METHODS

A total of 25 healthy subjects provided urine and blood samples for the study. All subjects had a negative BTA stat test initially. Normal urine was mixed with autologous blood to cause hematuria of 3 degrees of severity. The test was performed in each sample after the creation of hematuria.

RESULTS

BTA stat assay specificity in the presence of microscopic and gross hematuria was 80% and 24%, respectively. Results varied depending on the severity of hematuria, that is 20% for microscopic and 76% for gross hematuria.

CONCLUSIONS

The results of the BTA stat test in the presence of microscopic hematuria must be interpreted in regard to the degree of hematuria. The test is not reliable in urine samples with gross hematuria due to a high false-positive rate.

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.

Genetic and molecular markers of urothelial premalignancy and malignancy

The molecular genetic changes reported in bladder tumors can be classified as primary and secondary aberrations. Primary molecular alterations may be defined as those directly related to the genesis of cancer. These are frequently found as the sole abnormality and are often associated with particular tumors. There are characteristic primary abnormalities involved in th production of low-grade/well-differentiated neoplasms, which destabilize cellular proliferation but have little effect on cellula "social" interactions or differentiation, as well as the rate of cell death or apoptosis. Other molecular events lead to high-grad neoplasms which disrupt growth control, including the cell cycle and apoptosis, and which have a major impact on biological behavior. A primary target leading to low-grade papillary superficial bladder tumors resides on chromosome 9, while p53 gene alterations are commonly seen in flat carcinoma in situ. Other molecular alterations must be elucidated, as many non-invasive neoplasms have neither chromosome 9 nor p53 alterations. Novel approaches utilizing tissue microdissection techniques an molecular genetic assays are needed to shed further light on this subject. Secondary genetic or epigenetic abnormalities may be fortuitous, or may determine the biological behavior of the tumor. Multiple molecular abnormalities are identified in most human cancers studied, including bladder neoplasms. The accumulation, rather than the order, of these genetic alterations may be the critical factor that grants synergistic activity. In this regard, it is noteworthy that many of the genes that are altered act upon the two recognized critical growth and senescenc pathways, TP53 and RB. These particular molecular aberrations may be especially important to evaluate for their use in the management of bladder cancer because of their commonality in progressive forms of the disease. Thus, clinical trials are underway to explore their use in specific situations, particularly in the surgical management of locally advanced disease, and to determine whether adjuvant chemotherapy in such patients may be of benefit. The use of molecular alterations in the management of non-invasive bladder neoplasms remains to be firmly established. Our knowledge of molecular alterations important in bladder cancer progression is far from complete, and further study is necessary to further elucidate cruci pathways involved in progression and therapeutic response. As per preneoplastic conditions, difficulties in identifying and interpreting the significance of phenotypic changes have imposed certain limitations, as has an evolving nomenclature and issues of reproducibility in interpreting morphologica criteria. Nevertheless, molecular alterations involving chromosome 9q and the INK4A locus in papillary superficial tumors vs changes in chromosomes 14q and 8q, p53 and RB in flat carcinoma in situ lesions may indicate a molecular basis for early events that lead to varying pathways in urothelial tumorigenesis. Studies aimed at revealing the clinical relevance of genet instability, as well as molecular or epigenetic alterations, in urothelium and preneoplastic lesions of otherwise morphologicall normal appearance are needed to further advance knowledge in the field. Clinical advances in bladder cancer will be facilitated by novel animal models paralleling the human disease. Molecular diagnostics, particularly specific antigen expression, fluorescence in situ hybridization and microsatellite analyses, have show great promise as screening and follow-up methodologies, and may supplement urine cytology in the diagnosis and characterization of new and recurrent disease. In addition, the use of high-throughput genomic/proteomic assays, linked to comprehensive databases, and coupled with robust bioinformatics will be key elements in elucidating the components of regulatory and signaling pathways involved in bladder tumorigenesis and cancer progression.

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.

Urine based markers of urological malignancy

PURPOSE

A number of urine based markers have been and are being investigated for the diagnosis and prognostication of urological conditions. A majority of these markers have been evaluated in urological neoplasms, particularly bladder cancer. The diagnosis of bladder cancer currently relies on identifying malignant cells in the urine and subsequently visualizing the tumor on cystoscopy. This diagnosis is further confirmed by transurethral resection or biopsy. While urine cytology is specific, it is not sensitive, especially for detecting low grade disease. This characteristic has prompted the search for more accurate markers of bladder cancer. In this review we critically examine the results of studies evaluating various markers for bladder cancer.

MATERIALS AND METHODS

The published literature on urine based markers for all urological diseases, particularly bladder cancer, was identified using a MEDLINE search and critically analyzed. The sensitivity, specificity, positive and negative predictive values of the various markers were compared. The benefit of using combined markers rather than a single marker was also analyzed from published reports.

RESULTS

Most published literature on urine based markers for urological malignancies involve such markers for diagnosing and prognosticating bladder cancer. Hence, we focused mainly on urine based markers in bladder cancer. Most markers appear to have an advantage over urine cytology in terms of sensitivity, especially for detecting low grade, superficial tumors. However, most markers tend to be less specific than cytology, yielding more false-positive results. This scenario is more common in patients with concurrent bladder inflammation or other benign bladder conditions. However, there is reason to be optimistic about several new markers that appear to provide better specificity. Few urine based markers have been identified and investigated in other urological tumors.

CONCLUSIONS

Detecting bladder cancer using diagnostic markers still presents a challenge. A number of new markers are currently available that appear to be significantly more accurate than cytology. However, further studies involving a larger number of patients are required to determine their accuracy and widespread applicability for diagnosing bladder cancer. Urine based markers do not appear to have a significant role in the diagnosis or prognosis of other urological malignancies, such as prostate, kidney or testicular cancer.

Diagnostic accuracy of DNA image cytometry and urinary cytology with cells from voided urine in the detection of bladder cancer

OBJECTIVES

To assess the potential of DNA image cytometry in screening for bladder cancer, compare it with conventional urinary cytology, and evaluate its possible use in routine urinary evaluation. Urinary cytology is still the most common method for detection of bladder cancer in routine clinical use. The considerable shortcomings of urinary cytology include its low sensitivity in low-grade carcinomas and its poor reproducibility.

METHODS

Spontaneously voided urine specimens from 40 patients with grade 1 (n = 27), grade 2 (n = 10), and grade 3 (n = 3) histologically proven transitional cell carcinoma and 40 patients with symptomatic urologic disease of the bladder were analyzed by cytology and DNA image cytometry. The DNA content was determined by use of the CM-1 Cytometer according to the guidelines in the ESACP Consensus Report on Standardization of DNA Image Cytometry.

RESULTS

Urinary cytology yielded an overall sensitivity of 47.5%. Conventional analysis of DNA histograms measuring the presence of DNA stemline aneuploidy (1.8c > stemline ploidy [STP] > 2.2c) revealed a sensitivity of 62.5%; applying the stemline interpretation according to Böcking et al. increased the overall sensitivity to 75%. The specificity of both methods was 100%. DNA image cytometry demonstrated a high sensitivity in grade 1 tumors (70.4%) compared with cytology (26%).

CONCLUSIONS

In light of its highly improved sensitivity compared with urinary cytology, DNA image cytometry should be used to evaluate suspect urothelial cells in urinary cytology specimens. Since the method provides more objective and reproducible results with a specificity comparable to that of cytology, we encourage its primary application in the screening for bladder cancer, provided these results can be confirmed in a multicenter evaluation study.

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.

Clinical significance of negative and equivocal urinary bladder cytology alone and in combination with DNA image analysis and cystoscopy

BACKGROUND

We evaluated the individual and combined ability of cytology (CYT), image analysis (IA), and cystoscopy (CYSTO) to predict the presence of transitional cell carcinoma (TCC) at 6 months of follow-up in patients with or without a prior history of urothelial carcinoma and negative (NEG) or equivocal (atypical or suspicious) urinary CYT.

METHODS

Fifty-one patients (43 with prior TCC) provided 57 urinary samples that were evaluated by CYT and DNA IA. Forty-nine patients were evaluated by CYSTO. Disease status was reassessed at 6 months by a combination of clinical, CYSTO, CYT, and histologic follow-up.

RESULTS

At 6 months' follow-up, the incidence of recurrence for patients with diploid, broad diploid, or aneuploid DNA histograms was 38%, 73%, and 100%, respectively. In the same group of patients, 43% of patients with NEG and "atypical" CYT recurred compared with 83.3% of patients with "suspicious" CYT. The predictive value (PV) of a positive (+) CYSTO evaluation was 100%; however, a NEG CYSTO examination was correct in only 73% of cases. Sensitivities of CYT, IA, and CYSTO to predict recurrence were 54%, 59%, and 62.5%, respectively, whereas the combined sensitivity of all three modalities was 72%. The +PV of combined CYT and IA in patients with prior TCC was 90% with aneuploidy 100% specific for malignancy; the NEG PV of combined CYT, IA, and CYSTO was 70%. CYT, IA, and CYSTO were highly significant in predicting recurrence (P = 0.0017, P = 0.0026, and P = 0.0002, respectively) whereas tumor grade and degree of invasiveness as assessed on initial biopsy were not significant. However, 11% of patients recurred between 6 months to 1 year who had NEG CYT, NEG CYSTO, and NEG IA.

CONCLUSIONS

Diagnostic accuracy increases in patients with NEG or equivocal CYT if supplemented by DNA IA and CYSTO. In patients with no history of TCC, equivocal urine CYT and/or abnormal DNA IA can occur after chemotherapy, radiation therapy, or viral infection. In these patients, the combined approach together with accurate history is essential for correct diagnosis. For the small subpopulation of patients who recur but demonstrate no abnormalities on combined testing, more sensitive diagnostic tests, such as chromosomal abnormalities by in situ hybridization, need to be developed.

Bladder cancer: natural history, tumor markers, and early detection strategies

Transitional cell bladder carcinoma is characterized by a dichotomous, multichronotopic natural history. Low and moderate grade Ta lesions frequently recur, yet rarely invade, and carry an excellent prognosis with currently available treatments. High grade Ta lesions, tumors with lamina propria invasion (T1), and carcinoma in situ often progress to invasive disease, at which time overall prognosis is significantly decreased, despite various treatment alternatives. Although early detection of bladder tumors, prior to muscle invasion, should vastly improve our ability to save both bladders and lives, current methods of detection are neither sufficiently sensitive nor specific. Tumor marker analysis is an exciting new frontier in bladder cancer evaluation, and may have important applications to early detection strategies, in combination with simple hematuria testing and other selected noninvasive screening methods.

Biochemical analysis of a bladder-cancer-associated mucin: structural features and epitope characterization

Three monoclonal antibodies (mAbs), M344, M300 and M75, were shown to define a unique tumour-associated antigen (TAA) of superficial bladder tumours. The antigenic determinants are expressed on a very-high-molecular-mass component and, in about 50% of the positive samples, one determinant is also detected on a 62 kDa molecular species, observed only under reducing conditions. The objectives of the present study were to characterize further this TAA by analysing (1) the biochemical nature of the epitopes recognized by the three mAbs, and (2) the biochemical and structural features of the molecule bearing them. The antigenicity was resistant to heat denaturation, trypsin and alpha-chymotrypsin treatments but highly sensitive to papain and Pronase digestion. NaIO4 oxidation decreased reactivity to mAbs M344 and M300 but enhanced reactivity to mAb M75. The three determinants were insensitive to beta-galactosidase and alpha-L-fucosidase but were sensitive to Vibrio cholerae neuraminidase. None of the three mAbs reacted with ovine, bovine or porcine submaxillary mucins. Deglycosylation with O-glycosidase or trifluoromethanesulphonic acid completely abolished the reactivity of the mAbs whereas N-glycosidase F deglycosylation had no appreciable effect. The presence on the molecule of cryptic Gal(beta(1-3))GalNAc as a major core disaccharide was demonstrated by a heterologous sandwich assay using mAb M75 and peanut agglutinin. Thiol reduction using beta-mercaptoethanol increased mobility of the high-molecular-mass component in polyacrylamide gels. We thus conclude that mAbs M344 and M300 react with sialylated carbohydrate epitopes, and mAb M75 reacts with a partially cryptic and periodate-resistant sialylated epitope expressed on a typical secreted high-molecular-mass oligomeric mucin which we named MAUB for mucin antigen of the urinary bladder.

The role of nuclear matrix protein 22 in the detection of persistent or recurrent transitional-cell cancer of the bladder

Successful management of transitional-cell carcinoma of the urinary bladder is greatly dependent upon regular surveillance and early detection of persistent or recurrent carcinoma. The development of a highly sensitive urinary test for the detection of transitional-cell carcinoma of the bladder could have a dramatic impact on our ability to diagnose and monitor bladder cancer patients as well as influence the treatment outcome. The urinary level of the nuclear matrix protein, NMP22, has been found to be elevated in patients with urothelial malignancy. This has prompted the development of an immunoassay to quantitate urinary NMP22 and use it as a cancer-specific marker. We provide a summary of the studies completed with the immunoassay for urinary NMP22 as an indicator for the presence of transitional-cell carcinoma and compare the results with those obtained using other screening modalities.

Ancillary techniques in the followup of transitional cell carcinoma: a comparison of cytology, histology and deoxyribonucleic acid image analysis cytometry in 91 patients

PURPOSE

Voided urine and bladder washing cytology are used frequently in the evaluation of transitional cell carcinoma of the bladder. As part of an ongoing investigation we report on the role of deoxyribonucleic acid (DNA) image analysis cytometry as an adjunct to cytology in the followup of patients with transitional cell carcinoma.

MATERIALS AND METHODS

Urine cytology and image analysis cytometry were performed independently on aliquots of voided urine, catheterized urine or bladder washings from 91 patients with previous or active transitional cell carcinoma of the bladder, and the results were compared to those of concurrent biopsy and clinical followup.

RESULTS

Of 75 recurrent transitional cell carcinomas 42 were detected by cytology, while 63 and 64 were identified by image analysis cytometry and biopsy, respectively, for a sensitivity of 57, 84 and 85%, respectively. Combined cytology and image analysis cytometry detected 67 recurrences, for an overall sensitivity of 89%. Of 11 cases undetected by concurrent biopsy 9 had abnormal DNA histograms with transitional cell carcinoma at followup and 2 were DNA diploid but with grade 1 transitional cell carcinoma at followup. Of 12 cases undetected by image analysis cytometry 8 were grade 1 and 4 were grade 2 transitional cell carcinoma.

CONCLUSIONS

Urine cytology and image analysis cytometry detect most recurrent tumors. Their combined use is indicated in the followup of patients with bladder transitional cell carcinoma.

MAUB is a new mucin antigen associated with bladder cancer

The M344 tumor-associated antigen, expressed in 70% of superficial bladder tumors, is a sialylated carbohydrate present on a high molecular mass thiol-reducible secreted mucin, which we named MAUB for mucin antigen of the urinary bladder. Herein we studied the relationship between MAUB and other known mucins in the MGH-U3 bladder cancer line where MAUB expression is modulated by culture conditions. Northern blots, immunoradiometric assays, and Western blots showed that only MUC1 and MUC2 are expressed in this MAUB-positive cell line. MUC1 differs from MAUB by its molecular mass and its non-oligomeric nature, while MUC2 has similar molecular mass and response to culture conditions. However, in double determinant immunoradiometric assays, MAUB and MUC2 did not cross-react. Moreover, confocal microscopy showed different subcellular localization of the two antigens. Treatment of MGH-U3 cells with MUC2 antisense oligodeoxynucleotides resulted in decreased expression of MUC2 and increased expression of MAUB, ruling out the possibility that monoclonal antibody M344 recognizes a different glycosylated form of MUC2. In addition, we identified a tumor specimen expressing MAUB but no MUC2 antigen or mRNA. Together, these results suggest that there is expression of at least three mucins in MGH-U3 cells and that MAUB is a cancer-associated mucin distinct from those identified so far.

Detection of bladder tumors by immunostaining of the Lewis X antigen in cells from voided urine

OBJECTIVES

A study was made to determine the sensitivity and specificity of immunostaining of the Lewis X antigen in exfoliated urothelial cells from voided urine, for the detection and surveillance of bladder tumors.

METHODS

Three consecutive voided urine specimens were obtained from 101 patients, 78 of whom were under surveillance because of a history of bladder tumors, and 23 were being evaluated because of hematuria or irritative urinary symptoms. Indirect immunoperoxidase staining of two urine samples was done on cytocentrifuge slides, using the P12 monoclonal antibody against the Lewis X antigen. The diagnosis of the presence of urothelial tumor was made if more than 5% of the cells showed a typical red-brown staining. Cytopathologic examination of the third urine specimen was done according to Papanicolaou. Each patient underwent cystoscopy, and biopsies were obtained whenever there was endoscopic evidence of bladder tumors or carcinoma in situ.

RESULTS

Cystoscopy and biopsies revealed transitional cell carcinoma in 32 patients, whereas 69 patients had no evidence of bladder tumors. Immunocytology of one urine sample showed true-positive results in 26 of the 32 patients with bladder tumors, corresponding to a sensitivity of 81.25%. When two samples were examined, a sensitivity of 97% and a specificity of 85.5% were obtained. When the results of cytology and immunocytology were combined, sensitivity reached 100%. High-grade and low-grade transitional cell tumors were detected with equal efficiency.

CONCLUSIONS

The use of P12 monoclonal antibody for evaluation of Lewis X reactivity in cytologic preparations from multiple voided urine specimens can improve the sensitivity of noninvasive detection of bladder cancer. The technique may ultimately replace cystoscopy in monitoring therapeutic response and tumor recurrence.

Ploidy and Tn-antigen expression in the detection of transitional cell neoplasia in non-tumour-bearing patients

OBJECTIVE

To study the effectiveness of combining DNA ploidy and the blood-group related membrane antigen Tn as bladder tumour markers which have been individually associated with high tumour grade and poor prognosis. In particular to (i) determine whether use of these two markers would improve tumour detection compared with either alone, particularly of high grade disease and (ii) determine whether intermediate rates of marker expression would occur in bladder cancer patients with no current tumour compared with those with a tumour and a control group with benign prostatic hypertrophy.

PATIENTS AND METHODS

A total of 102 patients undergoing cystoscopic monitoring for either benign prostatic hyperplasia (BPH) or for transitional cell carcinoma (TCC) at the Repatriation Hospital and Flinders Medical Centre were included in the study. The patients comprised three study groups, those with BPH (n = 37), with TCC but no tumour present (n = 38) and those with TCC and a tumour present at cystoscopy (n = 27). Exfoliated cells obtained from bladder washings at cystoscopy were double-labelled using a monoclonal antibody to the Tn antigen and a DNA stain, propidium iodide and examined by flow cytometry.

RESULTS

Rates of marker expression in 27 patients with tumours were 30% for Tn antigen, 30% for aneuploidy and 48% for either marker. Marker expression was strongly associated with tumour grade, with no expression at grade 1, 38% (3/8) tumours at grade 2 and 90% (9/10) at grade 3. In patients with a history of bladder tumours but no current tumour, rates were intermediate (30%) compared with patients with current transitional cell carcinoma (42%) and control patients (19%).

CONCLUSION

The use of Tn antigen combined with DNA flow cytometry can increase tumour detection, particularly of high grade, aggressive disease. Gradation of expression of these markers across patient groups at increasing risk of a tumour, with intermediate expression in patients with no current tumour, suggests that marker expression may be detecting a preneoplastic stage of the disease, which is not possible with cytology. Given two parallel disease processes for superficial papillary and for high grade disease with invasive potential, the expression of high grade tumour markers in cells from cystoscopically normal bladders may represent a pre-clinical stage of aggressive disease. The identification of patients at risk of invasive disease using combinations of tumour markers may offer advantages in clinical management, particularly when no tumour is present and therefore no histopathological assessment is made.