Comparative study of immunohistochemical analysis in tissues and molecular detection in exfoliated tumour cells in urine of human telomerase reverse transcriptase [hTERT] in urinary bladder cancer in Egyptians

Bladder cancer ranks the third most common malignancy in Egypt following to breast cancer and leukemia. Telomerase plays important roles in cancer development and promotion. Its activity is present in most human malignant tumor cells. Its activity was also detected in voided urine and in bladder washes of patients with bladder cancer, making it a potential marker for non invasive detection of bladder cancer in urine. The present study aims to correlate the expression of the hTERTmRNA in exfoliated tumour cells in urine to the in situ expression of hTERT protein in the corresponding tumour specimens and to evaluate the relationship to hTERT expression and the clinicopathologic tumour characteristics. The study comprised twenty three bladder cancer cases [22 urothelial and one squamous cell carcinomas]. Semiquantitative immunohistochemical detection of hTERT expression was evaluated using combined score evaluated by two examiners which included scoring of intensity and percentage of positivity Semiquantitative expression of hTERTmRNA relative to housekeeping gene GAPDH mRNA was evaluated from RNA extracted from exfoliated cells in urine. Expression of hTERT by immunohistochemistry [IHC] and RT-PCR was detected in 100% of the bladder cancer series. Both methods were significantly correlated [p=0.004]. There was no correlation detected between hTERT expression by both methods and clinicopathologic characteristics of the tumours represented by stage and grade. The high concordance between the semiquantitative expression of hTERT protein by IHC in tumour sections and hTERTmRNA in exfoliated tumour cells validate the potential use of hTERT as a diagnostic non invasive marker for diagnosis of bladder cancer in high risk Egyptian patients and in the follow up following cystoscopic resection of superficial tumours. To the best of our knowledge this is the first study which compares hTERT in situ expression in bladder tumours and hTERT mRNA in exfoliated tumour cells in urine

Study of the genotoxic effect of cyclophosphamide on albino mice bone marrow polychromatic erythrocytes -and the protective effect of captopril

Cyclophosphamide [CYP] is widely used as an antineoplastic and an immunosuppressive drug. However, it has been found to cause DNA damage in normal tissues as well. Captopril [CAP], an angiotensin converting enzyme inhibitor, was reported to have a potential protective effect on the genotoxic effect of CYP possibly through its antioxidant effect. The aim of the present work is to experimentally detect the genotoxic effect of cyclophosphamide using in vivo micronuclei assay in albino mice bone marrow polychromatic erythrocytes and to test the protective effect of captopril on reducing the genotoxicity of CYP. In the present study thirty adult male albino mice were equally divided into six groups. Group I [control group] animals received single physiological saline, group II mice received single injection of captopril [CAP] [50mg/kg], group III animals received single injection of 25mg/kg cyclophosphamide [CYP] dissolved in physiological saline, group IV mice received single injection of 50 mg/kg CYP dissolved in physiological saline, and groups V and VI were the same as group III and IV but CYP injection was preceded by CAP [50mg/kg] injection. The number of micronucleated polychromatic erythrocytes [MNPCEs] was determined in 1000 polychromatic cells from bone marrow smears obtained after sacrificing the animals 24 hrs from exposure to CYP or the control substance. Statistical comparison of the different groups showed that the difference between group I and II was not statistically significant [P=0.106], indicating that CAP does not induce genotoxicity. Whereas, comparing Groups III, IV to group I showed that the difference was statistically significant [P=0.013, 0.00021] It was observed that CYP increased the number of MNPCEs in a dose dependent way. Comparison of groups V and Vito groups III and IV respectively showed a significantly lower number of MNPCEs confirming a protective effect of CAP when administered prior to CYP. The results of the present study confirm a protective role of CAP and support the possibility of administration of captopril prior to cyclophosphamide to ameliorate its genotoxic effect and the possibility to develop secondary cancers

Study of genetic predisposition in Egyptian colorectal cancer patients: role of phase II xenobiotic metabolizing genes polymorphism

The glutathione S-transferase [GST] supergene family is an important part of cellular enzyme defense against endogenous and exogenous chemicals, many of which have carcinogenic potential. The present investigation was conducted to evaluate the possible association between genetic polymorphisms of glutathione S-transferase M1 and T1 [GSTM1 and GSTT1], and susceptibility to colorectal cancer and the interaction with environmental factors. A case-control study of 50 patients and 50 healthy controls was conducted to investigate the role of GSTM1 and GSTT1 polymorphisms in colorectal cancer. Genotypes of GSTM1 and GSTT1 polymorphisms were analyzed by multiplex polymerase chain reaction [PCR]. The frequencies of GSTM1 null and GSTT1 null genotypes in controls were 42% and 16%, respectively. The GSTM1 polymorphism was associated with an increased risk of developing colorectal cancer [p=0.002; OR=3.9, 95% CI 1.68- 9.15]. There was no significant association between GSTT1 null genotype and colorectal cancer risk. The GSTT1 deletions was associated with an increased risk of developing distal tumour [OR =5.25, 95% CI: 1.6-16.7, p=0.006]. GSTM1 null genotype was significantly more common in patients who were diagnosed before the age of 40 years than in those who were diagnosed at an older age. This suggests that the GSTM1 genotype might influence the age of onset of colorectal cancer. In conclusion, the results of the present study suggest that GSTM1 null genotype and combined GSTM1/T1 null genotypes may confer a genetic susceptibility to colorectal cancer. In addition, other environmental factors such as smoking may also have a contributing role