Decreased expression of Dkk1 and Dkk3 in human clear cell renal cell carcinoma.

The expression patterns of the Dickkopf (Dkk) family of proteins varies in different cancers. In the present study, the expression levels of Dkk1 and Dkk3 were investigated in clear cell renal cell carcinoma (ccRCC) tissues. Dkk1 and Dkk3 serum levels were also examined in patients with ccRCC, and the association between clinicopathological features and Dkk levels was investigated. Serum Dkk1 and Dkk3 were quantified using ELISA in 64 patients with ccRCC and in 30 healthy individuals (controls). The expression levels of Dkk1 and Dkk3 were analyzed in tumor and adjacent normal tissues obtained from patients with ccRCC (n=20) using quantitative polymerase chain reaction (qPCR), western blot analysis and immunohistochemistry. The mean serum levels of Dkk1 and Dkk3 in the patients with ccRCC were significantly lower than those in the healthy controls. Furthermore, the serum Dkk1 levels were significantly lower at higher tumor­node­metastasis stages and tumor grades. qPCR, western blot analysis and immunohistochemistry revealed a significant decrease in the Dkk1 and Dkk3 mRNA and protein levels in the tumor tissues compared with the adjacent normal tissues. Consequently, Dkk1 and Dkk3 may present a novel molecular target for the diagnosis and therapeutic treatment of ccRCC.

Statin use and risk of kidney cancer: a meta-analysis of observational studies and randomized trials.

AIM: Clinical studies have shown that statin use may modify the risk of kidney cancer. However, these studies yielded different results. To quantify the association between statin use and risk of kidney cancer, we performed a detailed meta-analysis of published studies regarding this subject. METHODS: A literature search was carried out using MEDLINE, EMBASE and the Cochrane database between January 1966 and October 2012. Prior to performing a meta-analysis, the studies were evaluated for publication bias and heterogeneity. Fixed effect and random effect models were used to estimate summary relative risks (RR) and the corresponding 95% confidence intervals (CIs). Subgroup analyses and sensitivity analysis were also performed. RESULTS: A total of 12 (two randomized controlled trials, five cohort, and five case-control) studies contributed to the analysis. There was heterogeneity among the studies but no evidence of publication bias. Pooled results indicated a non-significant decrease of total kidney cancer risk among all statin users (RR = 0.92, 95% CI 0.71, 1.19). Long term statin use did not significantly affect the risk of total kidney cancer (RR = 1.01, 95% CI 0.83, 1.22). In our subgroup analyses, the results were not substantially affected by study design, confounder adjustment and gender. Furthermore, sensitivity analysis confirmed the stability of the results. CONCLUSION: The findings of this meta-analysis suggested that there was no association between statin use and risk of kidney cancer. More studies, especially randomized controlled trials and high quality cohort studies with larger sample size and well controlled confounding factors, are needed to confirm this association in the future.

Long-term oncologic outcomes of laparoscopic versus open partial nephrectomy.

BACKGROUND: Most of the literatures on laparoscopic partial nephrectomy (LPN) versus open partial nephrectomy (OPN) focus on technical details and early or mid-term oncologic outcomes, reflecting that the approach is safe and provides midterm benefits compared with traditional open surgery. However, the difference of long-term oncologic outcome between LPN and OPN remains unclear. The aim of this meta-analysis was to evaluate the long-term oncologic outcome of LPN in the treatment of localized renal tumors compared with that of OPN. METHODS: A systematic search of electronic databases including Medline, Embase, and Cochrane library was conducted. Comparative studies reporting on long-term oncologic outcome of LPN versus OPN were regarded eligible. The odds ratio (OR) and its corresponding 95% confidence intervals (CI) were calculated for the oncologic outcomes. The methodologic quality of the included studies was evaluated using the strict criteria of the Newcastle-Ottawa scale. RESULTS: Six comparative studies (1495 participants including 555 LPN and 940 OPN) were included in the present study. There was no significant difference between LPN and OPN in 5-year overall survival (OS) rates (OR = 1.83, 95% CI (0.80, 4.19)), 5-year cancer specific survival (CSS) rates (OR = 1.09, 95% CI (0.62, 1.92)), and 5-year recurrence free survival (RFS) rates (OR = 0.68, 95% CI (0.37, 1.26)). CONCLUSION: The results of this meta-analysis revealed that there was no significant difference in long-term oncologic outcome between LPN and OPN for treatment of localized renal tumors.