Study on bladder cancer susceptibility and genetic polymorphisms of XPC, XPG, and CYP in smokers and non-smokers.

AIM: To investigate the gene susceptibility of bladder cancer and potential relation with smoking. METHODS: An analysis of SNPs were conducted among DNA repair genes of XPC, XPG, XRCC1, and six members of metabolic enzyme gene CYP 450 via TaqMan Probe-based polymerase chain reaction. A total of 130 patients with bladder cancer and 304 healthy controls were involved. RESULTS: Polymorphisms of XPC gene was related to bladder cancer. It was also related to smoking status in bladder cancer patients, as well as to tumour stage, male gender and older age. The XPG gene polymorphism was also related to bladder cancer yet it was prevalent in female non-smokers. No association was acquired for XRCC1 gene. The combination of more than 2 polymorphisms in DNA repair genes was associated with bladder cancer. No association was obtained in any of the metabolic enzyme gene of CYP450 with either bladder cancer or smoking status. CONCLUSION: DNA repair genes XPC and XPG could be related to carcinogenesis and tumour progression of bladder cancer. Confirmation within larger population was warranted.

REG1A predicts recurrence in stage Ta/T1 bladder cancer.

AIMS: Stage Ta/T1 urothelial carcinoma of the bladder (Ta/T1 BC) has a marked tendency to recur. Regenerating protein 1 A (REG1A) has been reported to be expressed in human cancers, and it may be positively correlated with patient's prognosis. The aim of the present study was to evaluate the prognostic value of REG1A in Ta/T1 BC. METHODS: Immunohistochemistry was done on 110 paraffin-embedded specimens of human Ta/T1 BC to detect the proteins REG1A, PCNA and MMP2. The relationships between REG1A expression and the clinical-pathological characteristics of Ta/T1 BC patients were evaluated. RESULTS: Sixty-five out of 110 specimens were REG1A-positive. Grade and expression levels of MMP2 and REG1A were significantly correlated with the recurrence rate. REG1A expression (Hazard ratio: 3.1; 95% CI: 1.1-8.5; P=0.030) was an independent predictor of recurrence rate in multivariate Cox regression analysis. A significant association between REG1A expression and MMP2 expression (P=0.023) was also observed. CONCLUSION: Expression of REG1A is an independent predictor of recurrence in Ta/T1 BC.

Extraperitoneal laparoscopic radical prostatectomy.

A total of 28 patients with clinically localized prostate cancer (PCa) underwent extraperitoneal laparoscopic radical prostatectomy (EP-LRP). The mean operative duration was 309 (287-600) minutes. Estimated blood loss ranged from 380 to 1000 (mean 480) ml. At 3 to 5 days postoperatively, the catheter was removed. No open conversion was required and no patient presented postoperative complications. PSA level was less than 0.1 ng/ml at 3 months after surgery in all patients. At a mean follow-up of 10 (6-16) months, there were no biochemical failures. The extraperitoneal technique potentially decreased the risk of intra-abdominal complications and better approximated than open retropubic radical prostatectomy. In conclusion, EP-LRP is an effective, safe and precise technique.

Apoptosis of lymphocytes in canine peripheral blood induced by shock vibration and its mechanism.

We investigated the mechanism of apoptosis induced by shock vibration in canine peripheral lymphocytes, the T-lymphocyte changes, and the expression of p53 and bax gene products related to apoptosis using the techniques of immuno- and enzyme cytochemistry. We noted obvious apoptosis after delivery of 80, 100, and 200 acceleration of gravity values (G values). The percentage of apoptotic lymphocytes was directly proportional to the G value. On the 3rd day after injury, the number of apoptotic lymphocytes reached the peak value, which was about 5 to 8 times the amount in the control group. On the contrary, on day 3 after injury, T lymphocytes decreased and were about 50% of the control group. On the other hand, we found that the percentage of p53 and bax-positive lymphocytes distinctly increased and, on the 3rd day after injury, their number was, respectively, about 2.3 and 1.8 times that in the control groups, suggesting that they may play an important role in lymphocyte apoptosis. The above-mentioned results provide an important basis for further study of the mechanism of shock-vibration injury, its prevention, and treatment.

Apoptosis of circulating lymphocytes induced by whole body gamma-irradiation and its mechanism.

We studied the apoptosis of mousecirculating lymphocytes and its mechanism induced by 2, 4, 6, and 8 Gy of whole-body gamma-irradiation and the expression of bax and bcl-2 gene products as related to apoptosis. We found that, in the early stage after irradiation (4th-7th day), the percentage of lymphocyte apoptosis increased rapidly. Four hours after 2, 4, 6, and 8 Gy of gamma-irradiation, the apoptotic lymphocytes were 2.6, 3.8, 5.5, and 10.4 times those in the controls, respectively. A good correlation was found between the intensity of apoptosis and the radiation dose. As the radiation dose increased, the absolute counts of peripheral lymphocytes decreased sharply; 4 hours after 2, 4, 6, and 8 Gy of gamma-irradiation, the lymphocyte counts were 82, 63, 47, and 22% of the controls, respectively. The peak value of lymphocyte apoptosis was observed on the 7th day after irradiation using the in situ terminal labeling method, and the apoptotic lymphocytes were found to be 16 times the number in the controls. These results were in accordance with those obtained by the May-Grünwald-Giemsa staining method. The absolute counts of peripheral lymphocytes dropped to their lowest value on the 7th day after irradiation, suggesting that lymphocyte apoptosis might be the major cause of lymphocytopenia in the early stage after irradiation. The abnormal expression of bax and bcl-2 gene products in irradiated lymphocytes was closely related to apoptosis in peripheral lymphocytes.