Using of telomerase enzyme in urine as a non invasive marker for cancer bladder detection

Urinary bladder cancer is one of the major health problem all over the world. Cystoscopy remains the gold standard for identifying bladder cancer but it is invasive and expensive, therefore, a simple, non invasive test for detecting bladder cancer would be helpful. Several biomarkers for bladder cancer have been used, but no single marker has been accurate and conclusive. The current study aimed to measure telomerase enzyme in urine as a useful non invasive marker for detection of bladder cancer. Forty eight patients [39 males and 9 females] were included, They are complaining of urinary symptoms and undergo cystoscopy with biopsy of bladder lesions and histopathological examination. They were divided into groups: Group I: 16 patients [11 males and 5 females] have benign urologic conditions. Group II: 32 patients [28 males and 4 females] have proven bladder cancer patients underwent transurethral resection of bladder tumor or cystoscopy with biopsy of bladder lesions. Also, 15 apparently healthy volunteers with matched age and sex with patients were served as a control group. All subjects were submitted to laboratory estimation of the following in urine: urinary creatinine, urine cytology, telomerase enzyme in urine by telomerase PCR and complete urine examination. The results of this study revealed that a highly significant increase in the frequency of cytolological positive cases for tumor cells in malignant group than each of benign group and healthy subjects, while no' significant difference was detected between benign group and healthy subjects. The frequency of telomerase in urine was significantly higher in malignant group than each of benign group and healthy subjects, while no significant difference was detected between benign group and healthy subjects. The telomerase activity has sensitivity of 90.6% for diagnosis of cancer bladder with 93.7% for specificity and PPV was 96.6%, NPV was 83.3% and diagnostic accuracy of 91.6%. While, urine cytology gives a sensitivity of 68.8%, specificity of 87.5%, PPV of 91.6%, NPV 58.3% and diagnostic accuracy of 75%. When combined tests were used the sensitivity raised to 96,8%, and specificity reached to 100%, PPV was 96.6%, NPV was 94.1% and diagnostic accuracy increased to 97.9%. the urinary assay of telomerase could be used as non invasive test to identify the bladder cancer patients and distinguish them from normal subjects and patients with benign tumor of urinary bladder. The low cost of this test may help to be implicated as non invasive screening of bladder cancer

Telomerase activity, cytokeratin 20 and cytokeratin 19 in urine cells of bladder cancer patients

This work aims to search for markers suitable for the screening of bladder cancer, which should be specific, sensitive, reproducible, non-invasive and at acceptable cost. The study included 50 patients diagnosed as bladder cancer [35 TCC, 15 SCC] of different stages and grades, 30 patients with various urothelial diseases, besides 20 apparently healthy subjects of matched age and sex to the malignant group. A random midstream urine sample was collected in a sterile container for the determination of telomerase by RT-PCR, keratin 19 by ELSA CYFRA 21-i IRMA kit, keratin 20 by RT-PCR and immunohistochemical staining, and urine cytology. For all parameters [telomerase, Ki9, K20 and cytology] the malignant group was significantly different from both the benign and the control groups. None of the four studied parameters was correlated to the stage of the disease, and when it comes to grade, only Ki9 showed a significant positive correlation with grade both in TCC and SCC. When ROC curves for all parameters were compared, Ki9 had the largest area under the curve, and then comes K20. K 19 may be used as a biological marker for the diagnosis of bladder cancer Ki9 could not be used for differential diagnosis of different types of bladder cancer, meanwhile it could be a marker for differentiation that decreases in less differentiated tumors. As a tumor marker, K20 reflects inability to differentiate tumor type or grade in TCC, while in SCC of the bladder it is correlated with the grade. As a method, RT-PCR is superior to immunostaining for the detection of bladder cancer, meanwhile K20 immunohistochemistry [IHC] results were much better than urine cytology as a bladder cancer screening test. Haematuria and inflammation reduced the specificity of telomerase assay, which reduced its validity as a tumor marker of bladder cancer. Ki9 and K20 are the best candidates as screening tests for the diagnosis of bladder cancer, representing the highest sensitivity and specificity, beside the radiological and histopathology. Meanwhile, telomerase, although it was a sensitive enough marker, it reflected a high false positive rate

Significance of telomerase activity, C-erbB2, malondialdhyde and NO as biological markers in urine of bladder cancer patients

At the National Cancer Institute [NCI], Cairo, Egypt, bladder neoplasm constitutes 30% of all cancers. Evaluation of urinary markers may hold a promising method for detection of bladder neoplasms with higher sensitivity and specificity, for follow-up in order to regulate the interval of cystoscopic examination, reduce the burden and discomfort of patients amid enhance the opportunities to excise the tumor preceding muscular invasion. The present study aims to evaluate the possible diagnostic role of telomerase activity, C-erbB2, malondialdehyde and NO in the urine of bladder cancer patients. Eighty urine samples were taken from 3 groups of individuals; 1] Ten healthy age matched control subjects, 2] Twenty schistsoma haematobium infested patients and 3] Fifty pre-operative bladder cancer patients. Urine samples [50mL] were collected and subjected to the assay of telomerase activity in urine [TAU], it was measured by PCR-ELISA technique using the telomerase repeat amplification protocol [TRAP], malondialdehyde and nitric oxide were determined spectrophotometrically and C-erbB2 was measured by ELISA technique. TAU was increased in 72% of bladder cancer cases, it was normal in bilhazial non malignant group compared to controls. Its increase in bladder cancer patients with bilharzial infection was statistically insignificant compared to non bilharzial cancer group. TAU of bladder cancer patients were increased in ascending manner with grades of the tumor [GI = 62.5 +/- 16.7, GII = 66.64 +/- 9.37 and GIII = 163 +/- 51]. Malondialdehyde level was increased in bladder cancer patients with bilharzial infestation than those without bilharziasis, but the difference was statistically insignificant. C-erbB2 expression was increased in 27% of bladder cancer patients; while no single case of the bilharzial group showed positive C-erbB2 expression. As regard the stage of tumor NO level in bladder cancer patients showed statistical significant difference between stage I. II amid stage III [p = 0.04]. There was only a statistically significant positive correlation between telomerase and C-erbB2 in bladder cancer patients [r = 0.456 and p = 0.005]. The study of telomerase activity in the urine of bladder cancer cases may be used as an indicator for early detection of this disease. Further studies should be done to evaluate the possibility of using telomerase as one of the most important tumor markers