IMMUNOSTAINING OF CYTOKERATIN 20 IN CELLS FROM VOIDED URINE FOR DETECTION OF BLADDER CANCER

Liquid biopsies for detection, surveillance, and prognosis of urothelial cancer: a future standard?

INTRODUCTION

Liquid biopsies are used for the detection of tumor-specific elements in body fluid. Their application in prognosis and diagnosis of muscle/non-muscle invasive bladder cancer (MIBC/NMIBC) or upper tract urothelial cancer (UTUC) remains poorly known and rarely mentioned in clinical guidelines.

AREAS COVERED

Herein, we provide an overview of current data regarding the use of liquid biopsies in urothelial tumors.

EXPERT OPINION

Studies that were included analyzed liquid biopsies using the detection of circulating tumor cells (CTCs), deoxyribonucleic acid (DNA), ribonucleic acid (RNA), exosomes, or metabolomics. The sensitivity of blood CTC detection in patients with localized cancer was 35% and raised to 50% in patients with metastatic cancer. In NMIBC patients, blood CTC was associated with poor prognosis, whereas discrepancies were seen in MIBC patients. Circulating plasma DNA presented a superior sensitivity to urine and was a good indicator for diagnosis, follow-up, and oncological outcome. In urine, specific bladder cancer (BC) microRNA had an overall sensitivity of 85% and a specificity of 86% in the diagnosis of urothelial cancer. These results are in favor of the use of liquid biopsies as biomarkers for in urothelial cancer management.

Diagnostic performance of an immunoassay based on urine exfoliated cell enrichment nanotechnology for upper tract urothelial carcinoma: a retrospective, monocentric study

BACKGROUND

Noninvasively urine-based diagnostic modalities for upper urinary tract urothelial carcinoma (UTUC) were still lacking. We evaluated the diagnostic value of our previously developed urine-based assay (UTC assay) in UTUC.

METHODS

We retrospectively analyzed 90 patients with suspected UTUC and 40 donors without UTUC. Voided urine specimens were analyzed by UTC assay and fluorescence in situ hybridization (FISH). The performance of UTC assay and FISH was compared among the 60 histologically proven UTUC patients and the 40 donors with benign disease.

RESULTS

Of the 60 UTUCs, there were 8 low-grade and 52 high-grade cases. Overall sensitivity for UTC assay and FISH were 85% and 73.3%, respectively (P = 0.116). Specificities for UTC assay and FISH were 92.5% and 95%, respectively (P = ns.). By grade, sensitivities of UTC assay and FISH were 87.5% vs. 37.5% for low-grade (P = 0.119), and 84.6% vs. 78.8% for high- grade UTUC (P = 0.446), respectively. By stage, UTC assay showed significantly higher sensitivity than FISH for detecting non-muscle-invasive UTUC, which were 88.5% vs. 61.5%, respectively (P = 0.025).

CONCLUSION

UTC assay has good performance for the non-invasive diagnosis of UTUC. UTC assay may improve the diagnosis and surveillance of low-grade or superficial UTUC.

Biomarkers for Precision Urothelial Carcinoma Diagnosis: Current Approaches and the Application of Single-Cell Technologies

Simple Summary

Urothelial carcinoma (UC) is the most frequently diagnosed cancer of the urinary tract and is ranked the sixth most diagnosed cancer in men worldwide. About 70–75% of newly diagnosed UCs are non-invasive or low grade. Different tests such as urine cytology and cystoscopy are used to detect UC. If abnormal tissue is found during cystoscopy, then a biopsy will be performed. Cytology has low sensitivity for low-grade cancer while cystoscopy is invasive and costly. Detecting UC early improves the chances of treatment success. Therefore, many researchers have painstakingly identified urine biological markers for non-invasive UC diagnosis. In this review, we summarize some of the latest and most promising biological markers (including FDA-approved and investigational markers). We also discuss some new technologies that can aid research efforts in biological marker discovery for early UC detection.

Abstract

Urothelial carcinoma (UC) is the most frequent malignancy of the urinary system and is ranked the sixth most diagnosed cancer in men worldwide. Around 70–75% of newly diagnosed UC manifests as the non-muscle invasive bladder cancer (NMIBC) subtype, which can be treated by a transurethral resection of the tumor. However, patients require life-long monitoring due to its high rate of recurrence. The current gold standard for UC diagnosis, prognosis, and disease surveillance relies on a combination of cytology and cystoscopy, which is invasive, costly, and associated with comorbidities. Hence, there is considerable interest in the development of highly specific and sensitive urinary biomarkers for the non-invasive early detection of UC. In this review, we assess the performance of current diagnostic assays for UC and highlight some of the most promising biomarkers investigated to date. We also highlight some of the recent advances in single-cell technologies that may offer a paradigm shift in the field of UC biomarker discovery and precision diagnostics.

Immunocytochemical staining for p53 and Ki-67 helps to characterise urothelial cells in urine cytology

OBJECTIVE

The presence of atypical cells in urine cytology is unsatisfactory for both cytologists and clinicians. The objective of this study was to test whether p53 and Ki-67 immunostaining could improve urothelial carcinoma (UC) detection on urinary cytology.

METHODS

A total of 196 urine samples were analysed, 142 from the bladder, 41 from the upper tract and 13 from ileal bladder replacement. Cytology results were expressed as normal (N) (n = 81), atypia cannot exclude low-grade UC (ALG) (n = 25), suspicious for high-grade UC (SHG) (n = 39) and high-grade UC (HG) (n = 51). Actual diagnoses were confirmed by histopathological analysis, cystoscopic examination or follow-up for at least 1 year. Immunocytochemistry performed on CytoSpin^™ slides allowed the determination of the percentage of positive cells with p53 and Ki-67.

RESULTS

The median percentage values [first to third quartile] of p53 and Ki-67 were 0 [0-5] and 0 [0-1] for N cytology, 5 [0-40] and 2 [1-10] for ALG, 10 [0-30] and 6 [3-25] for SHG, and 30 [10-80] and 20 [10-30] for HG, respectively. Statistically higher values were observed for both tests (P < 0.001) in positive cytologies (ALG, SHG and HG). The optimal cut-offs were 5% for p53 and 3% for Ki-67. The sensitivity and specificity for the detection of all UC were 86.4% and 76.7% for cytology alone, 81.3% and 93.2% for cytology and p53, 75.7% and 88% for cytology and Ki-67, and 68.9% and 97.5% for cytology, p53 and Ki-67, respectively.

CONCLUSION

Using p53 and/or Ki-67 in addition to cytology increases the specificity without penalising the sensitivity.

External validation of FXYD3 and KRT20 as predictive biomarkers for the presence of micrometastasis in muscle invasive bladder cancer lymph nodes

INTRODUCTION

Recent studies have proposed that FXYD3 and KRT20 mRNA quantified by quantitative reverse transcription polymerase chain reaction (qRT-PCR) in paraffin could be biomarkers to detect lymph nodes with micrometastases that avoid detection by conventional analysis with hematoxylin-eosin (HE). A validation study was conducted on the lymph nodes of patients who underwent radical cystectomy.

OBJECTIVE

To classify the adenopathic state of a sample of patients who underwent cystectomy, based on the lymph node expression of FXYD3 and KRT20. The secondary objective was to assess whether there is a differential oncologic evolution for the patients, depending on the lymph node expression of these proteins.

MATERIAL AND METHOD

The study included lymph nodes from 64 patients who underwent cystectomy for infiltrating bladder tumor: The model was developed using metastatic lymph nodes from 15 patients and lymph nodes from 4 patients with no known tumor. Genetic expression was measured using real-time qRT-PCR. We calculated (using qRT-PCR) the median expression of FXYD3 and KRT20 mRNA in the lymph node tissue. We then analyzed the receiver operating characteristic (ROC) curves, according to the function y=0.1400+0.250FXYD3-2.532. The cutoff was established using an ROC curve. The formula was applied to the remaining lymph node tissue, based on the previously established cutoff. The sample was classified into 4 subgroups: HE- qRT-PCR-, HE- qRT-PCR+, HE+ qRT-PCR+ y HE+, qRT-PCR-. A descriptive, comparative analysis was performed, as well as a metastatic progression-free survival analysis, calculating the Kaplan and Meyer curves for the 3 established subgroups. The test results were considered statistically significant at P<.05.

RESULTS

Using qRT-PCR, we verified that there were differences in the median expression of FXYD3 (P=.05) and KRT20 (P=.009) between the lymph node tissues of patients with benign prostate hyperplasia and those of patients with lymph node metastasis. A cutoff was assigned to 0.377. The sample was classified as follows: 37.5% of the patients were pN0 by HE and pN0 by qRT-PCR (-HE -qRT-PCR), 39.1% were pN0 by HE but metastatic by qRT-PCR (-HE +qRT-PCR), and 15 patients (23.4%) were metastatic by both techniques (+HE +qRT-PCR). The Kaplan and Meyer curves showed poorer metastatic progression-free survival for the patients who were +HE and +qRT-PCR than for the other subgroups, with no significant differences between -HE +qRT-PCR and -HE -qRT-PCR.

CONCLUSIONS

According to our results, 39.1% of the patients with infiltrating vesical tumors overexpressed the FXYD3 and KRT20 biomarkers and were N0 by HE. We observed no differential clinical behavior among the patients who underwent cystectomy according to their expression of FXYD3 and KRT20 when they were N0 by HE.

Evaluation of a triple combination of cytokeratin 20, p53 and CD44 for improving detection of urothelial carcinoma in urine cytology specimens

Background:

Atypical urine cytology results trigger cystoscopy or molecular tests, both of which are costly, complex and difficult to perform tests. Several immunostains are being investigated to improve cancer detection; however, cytology material is limited and restricts the use of multiple immunostains. This study was designed to determine the utility of a cocktail of three stains, cytokeratin (CK20), p53 and CD44 in urine cytology samples for improving the detection of urothelial carcinoma.

Materials and Methods:

Urine cytology specimens with cell blocks containing adequate cytologic material between 2005 and 2010 and subsequent follow-up biopsy and/or Urovysion test (102 cases including 29 negative, 56 atypical and 17 malignant) were included in the study and evaluated with the triple stain. Results were first validated on the positive and negative cases and then applied to the atypical cases to determine the utility in the diagnosis of urothelial carcinoma.

Results:

Based on the validation and published literature, two distinct immunoprofiles were defined – malignant, characterized by at least five CK20 and/or p53 positive atypical cells and reactive, all other staining patterns. The malignant immunoprofile showed 88% sensitivity, 78% specificity, 74% positive predictive value (PPV) and 90% negative predictive value (NPV) for detecting urothelial carcinoma. These values improved to 95% sensitivity and 96% NPV when low-grade urothelial carcinoma cases were excluded.

Summary:

Our results indicate that the triple stain is an inexpensive, easy to perform test most useful for differentiating high-grade urothelial carcinoma from its mimics. However Inclusion of CD44 in the cocktail did not provide additional value and is best excluded.

Raman molecular imaging: a novel spectroscopic technique for diagnosis of bladder cancer in urine specimens

BACKGROUND

Raman molecular imaging (RMI) is an optical technology that combines the molecular chemical analysis of Raman spectroscopy with high-definition digital microscopic visualization. This approach permits visualization of the physical architecture and molecular environment of cells in the urine. The Raman spectrum of a cell is a complex product of its chemical bonds.

OBJECTIVE

In this work, we studied the possibility of using the Raman spectrum of epithelial cells in voided urine for diagnosing urothelial carcinoma (UC).

DESIGN, SETTING, AND PARTICIPANTS

Raman signals were obtained from UC tissue, then from UC touch preps obtained from surgical specimens and studied using the FALCON microscope (ChemImage, Pittsburgh, PA, USA), with a×100 collection objective and green laser illumination (532 nm). Then, urine samples were obtained from 340 patients, including 116 patients without UC, 92 patients with low-grade tumors, and 132 patients with high-grade tumors. Spectra were obtained from an average of five cells per slide.

MEASUREMENTS

Raman spectroscopy of cells from bladder cancer (BCa) tissues and patients.

RESULTS AND LIMITATIONS

The Raman spectra from UC tissue demonstrate a distinct peak at a 1584 cm(-1) wave shift not present in benign tissues. The height of this peak correlated with the tumor's grade. The signal obtained from epithelial cells correctly diagnosed BCa with sensitivity of 92% (100% of the high-grade tumors), specificity of 91%, and a positive predictive value of 94% and a negative predictive value of 88%. The signal correctly assigned a tumor's grade in 73.9% of the low-grade tumors and 98.5% of the high-grade tumors. RMI for diagnosis of BCa is limited by the need for specialized equipment and training of laboratory personnel.

CONCLUSIONS

RMI has the potential to become a powerful diagnostic tool that allows noninvasive, accurate diagnosis of UC.

Bladder cancer biomarkers and their role in surveillance and screening

Early detection of bladder cancer and its recurrences is essential for improved prognosis and long-term survival. The detection and follow-up of these patients is currently based on cystoscopy, which is expensive and invasive, and, in most cases, cytology, which is non-invasive but not very sensitive. During recent years, many urine-based tests have been developed and tested in different patient populations. In this review we discuss new developments for biomarkers in bladder cancer that have potential use in surveillance and screening. In almost all publications authors compare sensitivity of the test with a concomitantly executed cystoscopy, for example, determine cross-sectional sensitivity. However, it has also been shown that false positive test results may be followed by a positive cystoscopy in the near future, showing that cystoscopy itself does not provide 100% sensitivity. This suggests that for a proper evaluation of urine-based tests, longitudinal studies should be carried out and the results communicated to the urologist.

Surveillance of patients with bladder carcinoma using fluorescent in-situ hybridization on bladder washings

OBJECTIVES

To compare the sensitivity and specificity of the UroVysion (Abbott Laboratories Inc., Downers Grove, IL, USA) fluorescent in-situ hybridization (FISH) assay to that of urinary cytology obtained from bladder irrigation during cystoscopic surveillance in patients with bladder carcinoma.

PATIENTS AND METHODS

The medical records were retrospectively reviewed for 41 consecutive patients screened at the authors' institution between August 2000 and December 2006 for recurrence of pathologically confirmed bladder cancer. All 162 cytology examinations and 141 FISH assay results obtained from bladder washing were included. Recurrence was determined by cystoscopy, bladder biopsy and upper-tract imaging. Sensitivity, specificity, positive predictive and negative predictive values were assessed using a chi-square distribution with one degree of freedom.

RESULTS

There were 24 men and 17 women (male to female ratio 0.59), the mean (range) age was 56 (33-73) years and the mean follow-up 30 (2-57) months. At the initial diagnosis, 35 of the 41 patients (85%) had superficial tumours (stage <or= T1), while six (15%) had muscle-invasive tumours (stage >or=T2). Twenty-six (63%) had low-grade and 15 (37%) had high-grade tumours. In 16 of 141 (11%) of the FISH assays and 16 of 162 (10%) of the cytological samples that were collected from bladder irrigations, there were too few cells for an adequate analysis. The FISH assay correctly correlated with subsequent cystoscopy, bladder biopsy or upper-tract imaging in 110/125 (88%) cases but not in 15/125 (12%). Cytology correctly correlated with the subsequent evaluation in 112/146 (77%) cases but did not in 34/146 (23%). When the FISH was compared with cytology in this setting, the sensitivity was 77% (30/39) vs 74% (37/50; P > 0.1), the specificity was 93% (80/86) vs 78% (75/96; P < 0.01), the positive predictive value was 83% (30/36) vs 64% (37/58; P < 0.05), and the negative predictive value was 90% (80/89) vs 85% (75/88; P > 0.1), respectively.

CONCLUSION

The UroVysion FISH assay obtained from bladder washings during cystoscopic surveillance of patients with a history of bladder cancer provides a similar specificity but greater sensitivity than that of cytology for detecting bladder cancer recurrences. Given the better specificity and similar sensitivity of UroVysion compared with urine cytology obtained from bladder washings, a reasonable approach might be to use the UroVysion assay as the primary marker for recurrence, with urine cytology used as a complementary examination.

Urinary cytokeratin 20 mRNA expression has the potential to predict recurrence in superficial transitional cell carcinoma of the bladder

Higher levels of cytokeratin 20 (CK 20) mRNA are expressed in malignant urothelial tissue compared to normal tissue. We determined the CK 20 mRNA expression in urine from patients with transitional cell carcinoma (TCC) of the bladder and assessed the biological behavior of such tumors in a 5-year follow-up. Second voided urine was preoperatively collected from 56 patients with bladder carcinoma, from 20 patients with nonmalignant urological diseases and from 40 healthy volunteers. RNA extraction from exfoliated urothelial cells was followed by quantitative real-time RT-PCR with the Light Cycler. Patients in the superficial TCC group had a median expression of 8226AU (arbitrary units) with and 1523AU without tumor recurrence (P=0.023). No such correlation was detected in the group with muscle-invasive tumors. Kaplan-Meier analysis revealed a significant difference between recurrent and nonrecurrent disease (P=0.019) in superficial but not in muscle-invasive TCC (P=0.84). CK 20 mRNA expression in urine has the potential to identify patients at risk for recurrence of noninvasive papillary urothelial tumors. It helps to categorize patients prior to TUR-B, so that the cystoscopy interval during follow-up may be extended in those with low-risk superficial TCC.

Molecular markers in bladder cancer: A critical appraisal

The diagnosis of both primary and recurrent bladder tumors currently relies upon the urine cytology and cystoscopy. Neither of these diagnostic tools is completely accurate. Prognostication of bladder cancer is largely based on pathologic tumor grade and stage. Over the past 2 decades, there is accumulating evidence that like many other cancers, bladder cancer, too, has a distinct molecular signature that separates it from other cancers and normal bladder tissue. Bladder tumors of different grades and stages even possess unique, and specific genotypic and phenotypic characteristics. Although recognition of several of these molecular alterations is possible by analyzing tumor tissue, urine, and serum samples, few if any of these "molecular markers" for bladder cancer are widely used in clinical practice. These markers include some that can be applied during the diagnostic work-up of symptoms (e.g., hematuria), those under surveillance for recurrence of superficial disease and forecasting long-term prognosis, or response to chemotherapy. In this review of molecular markers for bladder cancer, effectiveness of markers in each of these categories that are identifiable in the urine of patients with bladder cancer was examined. Many of the diagnostic markers appear to hold an advantage over urine cytology in terms of sensitivity, especially for the detection of low-grade superficial tumors. However, most markers tend to be less specific than cytology, yielding more false-positives. This result is more commonly observed in patients with concurrent bladder inflammation or other benign bladder conditions. Although there are several candidate markers for assessing prognosis or response to chemotherapy, studies of large patient populations are lacking. Further studies involving larger numbers of patients are required to determine their accuracy and widespread applicability in guiding treatment of bladder cancer.

Bladder tumor markers beyond cytology: International Consensus Panel on bladder tumor markers

This is the first of 2 articles that summarize the findings of the International Consensus Panel on cytology and bladder tumor markers. The objectives of our panel were to reach a consensus on the areas where markers are needed, to define the attributes of an ideal tumor marker, and to identify which marker(s) would be suitable for diagnosis and/or surveillance of bladder cancer. Our panel consisted of urologists and researchers from Europe, Asia, and the United States who reviewed original articles, reviews, and book chapters on individual bladder tumor markers published in the English language mainly using the PubMed search engine. Panel members also met during 3 international meetings to write recommendations regarding bladder tumor markers. The panel found that the most practical use of noninvasive tests is to monitor bladder cancer recurrence, thereby reducing the number of surveillance cystoscopies performed each year. Markers also may be useful in the screening of high-risk individuals for early detection of bladder cancer. However, more prospective studies are needed to strengthen this argument. Case-control and cohort studies show that several markers have a higher sensitivity to detect bladder cancer. However, cytology is the superior marker in terms of specificity, although some markers in limited numbers of studies have shown specificity equivalent to that of cytology. Our panel believes that several bladder tumor markers are more accurate in detecting bladder cancer than prostate-specific antigen (PSA) is in detecting prostate cancer. However, bladder tumor markers are held to a higher standard than PSA. Therefore, use of bladder tumor markers in the management of patients with bladder cancer will require the willingness of both urologists and clinicians to accept them.

Cytokeratin-20 immunocytology in voided urine exhibits greater sensitivity and reliability than standard cytology in the diagnosis of transitional cell carcinoma of the bladder

OBJECTIVES

To investigate whether immunocytochemical detection of cytokeratin (CK)-20 could serve as a reliable diagnostic marker for transitional cell carcinoma (TCC) of the bladder.

METHODS

A total of 232 patients were enrolled in the study. Group 1 consisted of 144 patients with histologically confirmed TCC (62 at diagnosis and 82 in follow-up), and group 2 consisted of 88 subjects, including healthy volunteers and individuals with "non-TCC" conditions. Spontaneously voided urine specimens were obtained from each patient and submitted to immunocytologic and standard cytologic examination.

RESULTS

CK-20 immunocytology yielded an overall sensitivity of 65.3%, significantly greater than the sensitivity of urine cytology (54.2%, P = 0.013). A more detailed analysis revealed a sensitivity advantage for the former technique in the detection of primary (61.3% versus 51.6%, P = 0.046), recurrent (68.3% versus 56.1%, P = 0.027), Stage pT1 (81.8% versus 59.1%, P = 0.006), grade 2 (76.2% versus 61.9%, P = 0.031), and grade 3 (82.1% versus 67.9%, P = 0.039) tumors. Moreover, CK-20 immunocytochemistry demonstrated greater overall specificity than cytology (90.9% versus 86.4%, respectively), a difference stemming from the subgroup of lithiasis patients (100% versus 66.7%, P = 0.024). In terms of reliability, the positive and negative predictive values of the immunoassay were greater than those calculated for cytology (92.2% versus 86.7% and 61.5% versus 53.5%, respectively).

CONCLUSIONS

CK-20 immunocytology is more sensitive than standard cytology in the detection of TCC, particularly of Stage pT1, grade 2, and grade 3 tumors. In view of its high overall specificity and predictive accuracy, it is conceivable that the proposed immunoassay may progressively replace conventional cytologic screening in the diagnosis of bladder cancer.

Quantitative detection of cytokeratin 20 mRNA expression in bladder carcinoma by real-time reverse transcriptase-polymerase chain reaction

OBJECTIVES

To determine cytokeratin 20 (CK 20) expression in tumor tissue, normal urothelial tissue, bladder washings, and urine from patients with urothelial carcinoma by real-time reverse transcriptase-polymerase chain reaction using the LightCycler Instrument.

METHODS

Urine, bladder washings, tumor, and normal urothelial tissue were obtained from 33 patients with bladder carcinoma. RNA was subsequently extracted. Twenty tissue samples from healthy volunteers were used as controls. Real-time reverse transcriptase-polymerase chain reaction with the LightCycler was performed using fluorescence-labeled CK 20 primers as the target gene and the porphobilinogen deaminase housekeeping gene as the internal standard.

RESULTS

CK 20 mRNA expression was detected in all samples investigated. CK 20 expression in the tissue and urine samples from patients with tumor was significantly increased compared with that in normal urothelial tissue (P = 0.028) or urine from the negative control group (P = 0.012). The average CK 20 expression was 70,140 arbitrary units (AU) in tumor tissue (30,533 AU in urine from patients with tumor) and 8460 AU in normal urothelial tissue (2234 AU in normal urine). A stage-related difference in CK 20 mRNA expression was observed in tumor tissue (P = 0.027) and for tumor grade G1-G2 versus G3 (P = 0.03).

CONCLUSIONS

CK 20 mRNA expression levels in tissue and urine were elevated in patients with urothelial carcinoma compared with the levels in healthy individuals. CK 20 expression was also detectable in normal urine or normal urothelial tissue, but at significantly lower levels than in tumor samples. Fluorescence-labeled quantitative polymerase chain reaction using the LightCycler helped to differentiate between low-level CK 20 expression in normal urothelial tissue and the levels in tumor tissue samples. CK 20 might be an excellent and sensitive marker for tumor monitoring and routine follow-up in patients with transitional cell carcinoma.

Advances in the clinical laboratory assessment of urinary sediment

Urinalysis has been used extensively in clinical practice to aid in the diagnosis of various renal and urologic diseases. The innovation of urinalysis is marching on right along with the rapid developments in biotechnology and astride from the solo urine cytology to sophisticated studies of individual component in the urinary sediment. In this review article, we focus on the use of flow cytometry and other technical advances in the examination of urinary sediment, the detection of urologic malignancies by the presence of microsatellite alteration in the urinary sediment, as well as the quantification of cytokine messenger RNA (mRNA) expression in urinary sediment by reverse transcription and real-time quantitative polymerase chain reaction (RT-QPCR). Notably, the study of cytokine mRNA expression in urinary sediment by RT-QPCR has recently been reported to provide important diagnostic information in kidney allograft recipients and patients with lupus nephritis. This simple and non-invasive method requires further study to determine its role in risk stratification and monitoring of therapeutic response in patients with other kidney diseases.

VALUE OF REVERSE TRANSCRIPTION POLYMERASE CHAIN ASSAY IN PERIPHERAL BLOOD OF PATIENTS WITH UROTHELIAL CANCER

PURPOSE

The nested reverse transcription polymerase chain reaction (RT-PCR) method was used to determine expression of uroplakin II (UP II) or cytokeratin 20 (CK-20) in cells separated from the peripheral blood of patients with urothelial cancer. We examine whether UP II or CK-20 expression can be used as a urothelial cancer marker for urothelial cancer in cells isolated from peripheral blood.

MATERIALS AND METHODS

Peripheral blood was taken from 20 healthy volunteers without a history of urothelial cancer, from 10 patients with a negative bladder biopsy for urothelial cancer and from 108 patients with urothelial cancer. Results of a nested RT-PCR assay were compared with pathological stage and recurrence.

RESULTS

None of the peripheral blood samples from the control subjects revealed a positive polymerase chain reaction result. Among 108 patients with transitional cell carcinoma of the bladder nested RT-PCR for UP II was positive in 25 (23%) versus 31 (29%) for CK-20 (p >0.05). Nested RT-PCR for UP II was positive in 5 (8%) patients with superficial stage disease (pTa and pT1) versus 8 (11%) positive for CK-20. Nested RT-PCR for UP II was positive in 15 (58%) patients with a stage of pT2 or advanced stages versus 17 (65%) positive for CK-20. Nested RT-PCR for UP II was positive in 13 (20%) and 10 (56%) patients with grades 2 and 3, respectively, versus 17 (27%) and 12 (67%) nested RT-PCR positive for CK-20. A significant difference in the Kaplan-Meier recurrence-free actuarial curve was noted among patients with superficial stage who were positive and negative on nested RT-PCR for UP II and CK-20 in peripheral blood, respectively, but not in the invasive stage. On multivariate analysis nested RT-PCR for UP II and CK-20 in peripheral blood were independent prognostic factors in patients with superficial stage disease but not with invasive stage disease. Lung and/or liver metastasis developed in 5 (80%) of 6 patients whose results after chemotherapy (consisting of cisplatin, doxorubicin hydrochloride, vinblastine sulfate and methotrexate) for nested RT-PCR for UP II and CK-20 remained positive.

CONCLUSIONS

These results seem to indicate that UP II and CK-20 mRNA in the blood may be useful tumor markers for predicting patient survival and the extent of urothelial cancer.

Detection of bladder tumours: role of cytology, morphology-based assays, biochemical and molecular markers

PURPOSE OF REVIEW

Cystoscopy is currently considered the gold standard for the detection of bladder tumours. The role of urine cytology in the initial detection and follow-up of patients is under discussion. Many efforts have been made to increase the detection rates and to predict the outcome of bladder cancer. In this subject review, a series of morphology-based, biochemical and molecular markers were compared with urine cytology for the detection of bladder cancer.

RECENT FINDINGS

Among the various markers reviewed, the average published sensitivity and specificity for the Bard tumour antigen test was 60 and 77%; for the nuclear matrix protein 22 test it was 67 and 72%; for the hyaluronic acid and hyaluronidase test it was 91 and 84%; for the ImmunoCyt it was 90 and 75%; for fluorescence in-situ hybridization it was 85 and 95%; for the telomerase assay it was 77 and 85%; and for the microsatellite assay it was 89 and 100%. DNA ploidy measurements, recent molecular markers and immunoassays designed to detect keratins, proteins, cell adhesion molecules, fibrinogen degradation products, and fibrinolysis markers were also included.

SUMMARY

As is clear from the brief summary of available assays, the optimal method of application is not yet clear. The integration of an assay into clinical practice takes more than just the documentation of its sensitivity and specificity. However, several of the procedures have received considerable support from urologists as assisting them in the management of their patients.

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.

Evaluation of cytokeratin-19 & cytokeratin-20 and interleukin-6 in Egyptian bladder cancer patients

OBJECTIVES

This study was designed to detect the expression of CK-19 and CK-20 in tissue specimens and IL-6 in the sera (as a noninvasive maneuver) of bladder cancer patients. Results were correlated with the clinico-pathologic parameters, Bilharziasis and the occurrence of relapse of the carcinoma among Egyptian bladder cancer patients.

METHODS

Subjects of this study were 50 cases of bladder carcinoma (19 cases were positive for Bilharziasis) as well as 20 cystitis cases as control (7 cases were positive for Bilharziasis). Messenger ribonucleic acid extracted from fresh frozen tissue specimens with bladder tumor and the control group were collected and subjected to RT-PCR to detect expression of the amplification bands of CK-19 and CK-20 (214 and 370 base pairs). In the mean time, Interleukin-6 was quantified in the sera of the patients using ELISA kit.

RESULTS

CK-19 and CK-20 RNAs were expressed in bladder cancer cases, but not expressed in the control group. They were significantly correlated to advanced tumor stage and grade, while CK-19 positivity, was also, correlated to tumor recurrence and tumor pathology being more in SCC than TCC. Moreover, IL-6 positivity was correlated to the occurrence of malignancy, advanced grade and pathology being more in SCC than TCC. ROC curve was utilized to choose the best cut-off for serum IL-6 (49.2 pg/mL). At the determined cut-off, the sensitivity was 66% and the specificity was 95%. Bilharziasis was found to be related to advanced stages and grades of bladder cancer.

CONCLUSION

CK-19, CK-20 and IL-6 were strongly associated with malignant phenotype of Egyptian bladder tissues, so they may be used as additional markers for assessment of bladder cancer patients.

Can biological markers replace cystoscopy? An update

Cystoscopy is currently considered the gold standard for the detection of bladder tumors. The role of urine cytology in the initial detection and follow-up of patients is under discussion. New elaborative and rapid assays are available that may circumvent the low sensitivity and poor reproducibility of urine cytology. The methods that have been tested extensively are the nuclear matrix protein (NMP22) assay, the BTA stat assay, and the BTA TRAK enzyme-linked immunosorbent assay. Both outperform cytology in the detection of low-grade lesions. The specificity of both assays, however, lags behind that of cytology. The data from retrospective analyses are insufficient to justify clinical integration, and the need to replace cystoscopy with these novel assays remains to be proven.